Traffic and Transportation Studies 2010

Remote sensing has a great potential for enhancing current urban planning processes by offering a holistic view of a study area and providing detailed land cover/use information within. This study intends to evaluate the potentials of remote sensing in urban/transportation planning by studying the accuracy of two image processing software (ENVI and Definiens) on extracting urban land cover/use. Several satellite images from the City of Fredericton, New Brunswick, Canada, including Landsat ETM+, SPOT4, IKONOS, and QuickBird, are used. It is found that medium-resolution images, Landsat ETM+and SPOT4, are only good at extracting large-size homogeneous objects, such as vegetation and water bodies, but less powerful for identifying small urban features, including buildings, streets and parking lots. Later experiments focus on extracting these urban features with very high-resolution imagery from IKONOS and QuickBird. Study results show that both software packages have more or less problems in distinguish parking lots, streets and building roofs because of similar materials used and therefore, very close spectral signatures. The results show the object-oriented hierarchical algorithm applied to QuickBird images offers the highest accuracy for building and street extractions, when compared to other algorithms/images combinations (such as maximum likelihood/nearest neighbor applied to QuickBird or IKONOS). The producer accuracy of the two is 78% and 63% respectively and the corresponding user accuracy is 39% and 56%. The study results clearly indicate that a more advanced approach using auxiliary data, such as GIS and LIDAR, is necessary to achieve an accuracy level acceptable for any real-world planning applications.

In the viewpoints of both sustainability and development, this paper attempts to establish a backcasting analysis framework to assess the urban and transport policies for the developments of developing cities in the future. The proposed backcasting approach is based on a newly developed integrated model; and the stochastic frontier analysis method is adopted in the backcasting process to define the environmental efficiencies of various comprehensive policies' applications. With the urban transport development of Jabodetabek of Indonesia in the future studied using this backcasting framework, it is confirmed that such backcasting approach can substantially offer a reasonable assessment measure for the sustainable and efficient urban transport developments of developing cities.

The project METRASYS (Mega Region Transport Systems for China) funded by the Federal Ministry of Education and Research of Germany in the program of research for sustainability and co-funded by the Chinese Ministry of Science and Technology follows an interdisciplinary approach integrating spatial planning (new urbanism), transport science, engineering and political science in order to contribute to the mitigation of climate change. An important part of METRASYS is to assess the environmental impacts of the traffic management system and planned urban traffic developments on the basis of a Business-As-Usual (BAU) scenario. Linking technological developments with urban and transport-planning policies is one of the foci of this project activity: The identification of suitable strategies and policies is a prerequisite to ensure permanent and effective implementation of technological approaches.How the results of the analysis as well as alternative measures and instruments for the development of a climate and energy efficient transport system are discussed with local decision makers is reported. A geo information system (GIS) model is presented for spatial visualization to assist decision makers and stakeholders in their comprehension and evaluation of the effects of policy measures. The BAU scenario is also the basis for the analysis of the suitability of transport management as a Clean Development Mechanism (CDM). It will show how to this extent the collected vehicle probe data can be used. The development of the technical system for traffic management and its installation in Hefei will be reported. All information and results of the traffic management system are open for the public. The dissemination activities aim at a broader audience within China and worldwide. It is aimed at transferring the results of the project to different cultural and institutional contexts. Main written products are more comprehensive discussion papers presenting the state of research, new findings from the project and recommendations. An important task is the invitation of stakeholders of cities similar in size and function to show the technical system with all its options and functionality. Dissemination includes the participation on practical oriented conferences and workshops summarizing the key points of new findings of the project. The METRASYS homepage will provide up to date information such as reports and an online GIS for stake holders, academia, and the public.The paper will give an overview about the specialties in the project work with the Chinese Partners and will point out the findings and goals of the described showcases.

Land use evaluation is the basis for sustainable development of freeway construction. Based on the investigation of the sustainable use of land resources, the inherent nature of sustainability land use of freeway construction was analyzed. An assessment indicator system about freeway land use was established according to the freeway functional requirements, site characteristics and present land use problems in freeway construction. Through a comprehensive consideration of coordinated development in society, economy, resource, and environment, an exponential growth curve land use evaluation model was established which was based on a method named same indefinite-contrary order of set pair analysis (SPA). The model was applied in freeway land use evaluation of China. The results showed that the evaluation model had a convenient and practical feature in calculation, strongly contrasting, and also has a better objective rationality.

The interaction between transport and social welfare is one of the most complex problems in Africa. It is a challenge of intertwined disciplinary issues of science — both social and natural sciences. It begs interdisciplinarity. This paper explores the future of interdisciplinarity in research on the continent through two lenses. First, through a rendering of drivers and agencies of research on the continent. Secondly, by presenting an analysis of the process of policymaking in the transport sector. Development of research in 16 countries of East, Central, and West Africa is traced back to pre-independence. An emerging model of research on the continent is presented. The model identifies weak linkages between private firms and public research institutions as the hindrance to the growth of interdisciplinarity on the continent. As regards transport policymaking, six regional policy initiatives were considered. This strand of the enquiry identifies the absence of local research entities in the policy process as the main obstacle to interdisciplinarity; the local research entities would in turn require strong private sector participation for vibrant interdisciplinary research. The paper concludes that interdisciplinarity will come to bear. It could be through a natural process of evolution, or through discrete action by donors, local political actors and universities.

As a transport mode, the taxi is often given scant attention. The mode is consistent, in appearance and function, and has followed the same patterns of licensing, rather than mainstream transport, from its origin as the first licensed public transport mode to current day arguments between regulation, whether a market operates better under a controlled or de-restricted model. The apparent lack of reporting does not, however, equate to a lack of analysis. Indeed a significant staple of consultancy and authority work exists. This including, in most mature markets, reporting specific to regulation; much of which is focused on the choice between a restriction placed on the numbers of licenses issued and the, apparent, alternative of allowing free market entry. Underlying the current, often complex, approaches to market form and its analysis, is the simple question, whether there is a "golden number" of taxis that should be provided in any one location; and whether there is a "golden rule" against which this number can be established. Indeed whether either open market access or controlled determined restriction can achieve an optimal solution.

Beijing is a city with a history of about 3,000 years. In the past several decades, pursuing to be industrialized used to be a main goal of the city which caused more and more serious pollution problems. Since the late of 1990s, actions have been taken to deal with the air pollution in Beijing in order to enhance living level of its residents. However, countermeasures taken firstly were almost on the adjustment of development routine of industry. Until recent years, especially approaching the 2008 Olympic Games, complicated schemes on green transport was concretely carried out. It was not only aiming for a currently clean air, but also a future sustainable development of transport and urbanization. Among the actions taken on green transport, there are exploration of low emission vehicles, priority to public transport, cycling and walking improvement and intelligent information techniques application. This paper summarizes these action schemes and what's on now in Beijing.

Shanghai is one of the largest prosperous cities in China with the population over 17million. From the 1940's the major urban planning strategy is trying to de-centralize the overcrowded population in the central part of the city, where the density was even as high as 70000 people/sq.km, now decreased to 40000 people/sq.km. The still very high dense city contributes relative less motorized travel, as over 50% of people travel by foot and bike. But it also creates the problem of congestion in the city center, degenerated quality. And the rapid growth claims more space to accommodate more diversity and dynamic economic activities. The tendency shows Shanghai should transfer its spatial structure from Mono-center to Poly center. But the de-centralization strategy to encourage the people stay in the satellite town has not been success. Recently the municipal government has put great attention to support the secondary city in the suburb of Shanghai, according to the plan the most important three new towns will be with the population of one million. More and more industry has also been moved out to the suburb due to the lower cost for land and convenient for freight transport. In the year 2010, the world expo will be held in shanghai, some major infrastructure is now under-construction, which including the 400km metro system, and several the major passenger interchanges, all those will have a big influence on the spatial structure of Shanghai Region. The transformation of shanghai urban planning policy and the vision of the urban spatial structure will be analyzed in this paper.

Review the 30 years of the Guangzhou transportation development course. Combining the requirements for transportation from urban master planning, it prospects the development opportunity and challenge facing the city from the urban primacy index and rail transit function orientation. On the basis of analyzing deeply the idea of human-oriented, it makes clear the key work to be done in next 10 years. Strengthening the pivot position (external) and constructing a public transit city (internal) are the two basic tasks. It has made "124" Comprehensive the transportation development strategy. The strategic objective is constructing a harmonious transportation system, which is sharing, fluent, intensive, green, and fair. It has made two core policies, which were transport facilities leadership and public transport priority. It introduced the strategy idea briefly from four respects, such as integration, differentiation, intensification, and refinement.

The market for urban passenger transport has experienced major change in many developing countries in Africa, Asia, and the Middle East, as well as in countries of political and/or economic transition in the Commonwealth of Independent States (CIS) and China. Such changes have included planned market opening to private operators and new entrants; unplanned market opening by the entry of unlicenced operators; privatisation and other changes to the ownership base of large public-sector transport companies; emergence of large-scale minibus and paratransit; national and urban policies and programs to upgrade the transport supply and quality. This paper presents relevant developments in Africa, Asia, Middle East, the CIS and China, and clusters them according to (i) changes in the role of the regulator and market structure; (ii) changes in the structure of the operator and of private sector participation; and (iii) changes in the transport supply. The paper then identifies critical factors leading to change in the urban transport sector, factors which can be identified with successful outcomes and issues associated with the development of the minibus, paratransit and informal sector which have played major roles in the urban transport sector of developing countries and countries in transition.

With the huge change of the international freights between China and Japan in contents and quality, it is needed to construct the new transport system with high certainty, punctuality, reliability and security for the logistics services with greater sophistication and diversity. This paper firstly analyzes the actual situations of China-Japan's international trade and relevant freight, and the relevant issues of conventional marine transport. Then, an intermodal transport system for these freights with the use of rail container and RORO/Ferry ship is described conceptually. Finally, the availability of the international freight transport system is confirmed through a case study based on the pots of Shanghai and Hakata.

Hunan Province plans to initiate larger scale construction of "3+5" city group on the basis of the Changsha-Zhuzhou-Xiangtan integration, in order to further enhance the radiation function of Changsha-Zhuzhou-Xiangtan integration, and to lead the development of surrounding areas,. The construction strategy is to make the central growth pole in Hunan Province's rising, which demands the ports of the pan-Changsha-Zhuzhou-Xiangtan "3+5" city group ports form rational port groups. The status and main functions of every port in port groups should be determined with primary-secondary order, clear levels, and complementary functions. Gini coefficient and Hofer index are utilized to make quantitative reasearch to the spatial structures of ports in the pan-Changsha-Zhuzhou-Xiangtan "3+5" city group, which could give reference for the port planning in the economic integration of "3+5" city group, fully exert the integral beneficial function of "3+5" city group ,and provide construction reference for other port groups in China.

This paper develops a comprehensive model (MERS) to evaluate urban environmental measures which contribute to an eco-friendly city. The characteristic of MERS is a practical model which is based on Person Trip Survey data. MERS has two sub-models, Urban Activity Model and Evaluation Model. Urban Activity Model consists of Land Use Model and Transportation Model. Land Use Model estimates the volume of employee and populations. Transportation Model estimates transportation demand by mode, and car traffic volume on each road links. Evaluation Model consists of environmental evaluation model, quality of life evaluation model and economic evaluation model. Evaluation results can be represented on mesh unit or road network links. This paper will explain the framework of MERS and the results of a case study.

This paper analyzes the cost structure of urban bus operations in Yangon, Myanmar. The data regarding the revenues and costs of local bus operators are collected during the interviews with the bus companies, the bus control committees and individual bus owners. The operating cost includes the fuel cost, labor cost, maintenance cost, office cost and others. Then, the operating cost functions are estimated from the statistical approach. The results show that the marginal cost with respect to vehicle-km in the city-bus individual operators is much higher than in the truck-bus individual operators; that the city-bus individual operators have higher marginal cost with respect to vehicle-km than the truck-bus individual operators; and that the marginal cost with respect to number of vehicle for the city-bus individual operators is five-time higher than that for the truck-bus individual operators.

There has been a fast development of transport infrastructure to support the economic growth in China, which calls for more study on the relation between them. This study employs a production function method and a VAR (Vector AutoRegression) approach to study the relation with national empirical data. The result of production function method is discussable because the elasticity of infrastructure to the output is negligible and may be contradict to common knowledge. The explanation for this includes the data limitation and potential unfixed effects. It is also shown that the more developed areas benefit more from infrastructure than undeveloped areas. The VAR method shows that the infrastructure counts for a significant part of economic growth and a shock in infrastructure might lead to significant short-term effect on economic growth but small long-term effect. The causality of the infrastructure and economic development is vague in statistic meaning but it seems more likely the infrastructure explains the economic growth but not reversely.

Since Greenhouse gases (GHG) are believed to lead to global warming, emission of such gases are now considered an environmental threat that must be confronted. About 30% of the GHG emissions in the United States are from transportation sources. This is why, transportation planners, policy makers, and the public often wants to know what effects a transportation project or a policy decision will have on GHG emissions. How to estimate GHG emissions in planning stage of a project or at policy decision levels? The standard process involves running a travel demand model as well as a sophisticated vehicle emission model. Data requirements of most of these emission modeling tools strain the ability of travel demand models to produce inputs at sufficiently fine detail. Moreover, due to emission model's complexity, time-consuming data collection, and staff and project budget constrains, it may not be feasible for transportation professionals to apply such sophisticated tools for estimating vehicle emissions for all transportation projects. Rather a quick and easy approach would help planners/engineers to apply travel demand model for vehicle emission estimation. The purpose of this paper is to provide an overview of methodologies that can help estimate GHG emissions without requiring too much of difficult to find data. This paper will first provide an overview of the common approaches about applying travel demand modeling data for roadway vehicle emission estimation. Several quick and easy vehicle emission estimation approaches will then be described.

Today, numerous works conclude that transport seems to be completely coupled to economic growth. Therefore, as a direct consequence of economic development, transport sits today as one of the major final energy consumers and one of the most important sources of carbon dioxide emissions. Furthermore, in the absence of major technological change, this unsustainable situation will most undoubtedly get worse in the future. In this paper we analyze what different types of public policies aiming at sharp reductions in GHE emissions imply on passenger transport and how they can be linked to new behavior patterns affecting consumption and in fine freight transport. For this, we use the transport issues in the long term (TILT) model's core microeconomic choice model. In this manner, we explain the interest of a time management approach to adaptation strategies for GHE reductions.

This paper aims to verify the causal relationships among emission volume (mobile sources and stationary sources), air concentration, and health effects (1974–2006) in certified areas of Tokyo, Kawasaki, Osaka, Amagasaki, and Kita-Kyusyu, which were certified according to Japanese Pollution-related Health Damage Compensation law. Our first hypothesis was that an increase in the total emission volumes of suspended particulate matter (SPM), NOx, SO₂, and CO in these cities corresponded to a deterioration in the air quality. The second hypothesis was that the number of certified patients increases with the deterioration in air quality. To support the results of this correlation, the number of new patients, recovery, and mortality were assessed by a simple general equilibrium model. Finally, the comparability of the estimated results with the track record was estimated on the basis of the presence of high t-values.

To develop the public transportation system and change the passenger transport mode share, as well as to control the resorting to private cars have been considered one of the most effective methods to reduce carbon emission. This paper aims at determining an optimal mode share scheme for the urban passenger transportation system, which meets the carbon emission limitation and the government investment constraint at the lowest social cost. This optimal mode share scheme could work as a suggested mode split target for a low-carbon city. Stackelberg game theory based bi-level modeling is used as the modeling approach because there are multiple decision makers involved. The objective of the upper level model will work as decision making assistance for the government in determining an optimal mode share scheme of the urban passenger transportation system, which meets the low carbon emission, the government investment and some other constraints, at the lowest social cost, including pollution treatment fee for CO₂ and construction fee for different traffic systems in different district. Classic UE equilibrium based automobile traffic flow assignment model and Non-UE transit flow assignment method on the network is the second level; it is built on behalf of users' consideration, and to reflect the performance of network with the changing of mode share, as well as to build the loop between two levels with the changing of average speed of vehicles. Algorithm for bi-level modeling is also studied and a sample network is used to test the workability of the proposed modeling approach.

To improve the statistical indicators for road transport energy consumption and accurately analyze its energy consumption level of China, the article analyzes energy statistics scope, indicators, vehicle classification and energy consumption proportion of road transport in China, the United States, Britain and Japan. The horizontal and vertical comparison methods are used to propose differences in energy consumption statistics between China and developed countries and to put forward the trends of China's energy consumption for road transport. Studies have shown as follows: the scope of China's road transport energy consumption statistics has differences from the international accepted patterns; at present, energy consumption statistical indicators for China lack the conveying efficiency of transport vecicle; the proportion of China's energy consumption for road transport to the total society is far lower than that of foreign countries, but it can be rapidly increased in the future.

This paper describes an initial analysis of vehicle inspections and maintenance program for private cars in Jakarta and surrounding cities namely JABODETABEK, as regulated in the 2005 bylaw. The 2005 bylaw on air pollution control, which took effect on February 2006, stipulated that all private car owners must get their vehicles' emission tested twice a year based on in-use vehicle emission standard. We apply bivariate probit model for the likelihood of CO and HC emission violations given a set of vehicle characteristics. Data of passenger car emission measured randomly during on-road emission measurements at Jakarta city and surrounding cities Bogor, Depok, Tangerang and Bekasi in 1999, 2000, 2004 and 2005. The engine size, fuel system, vehicle maintenance quality and passenger car travelled kilometer per year play a significant role in determining the probability of emission test failure. Vehicle kilometer travelled per year is different based on the vehicle-type and its usage. To analyze household vehicle-type ownership in Jakarta city, we use person trip data in 2002 and apply Multinomial Logit Model. Household income, family sizes are play significant in determining vehicle-type owned by households. Vehicle type Jeep and SUV are less to use by the households compare to Sedan or passenger car. In order to pass CO emission test, empirical study confirm that a combination of lower use of high fuel consumption car is better than higher use of low fuel consumption car.

Freight transport has increased rapidly with the raid economic growth, leading to rising energy consumption and CO₂ emission. In this paper, taking the urban freight transport of Beijing as a case, three scenarios are established to evaluate the potential of CO₂ emission reduction based on system dynamics model. Scenario results show that freight turnover of Beijing will touch 80 billion t-km at the end of 2020, with an annual average growth rate around 5%, and the CO₂ emission mitigation potential range from 13–30% by 2020.

In this paper, we try to provide a simple analytical approach to describe distribution of intersection entering traffics on a grid road network. The approach is a continuous model with explicit structure and free of the need of a detailed OD (Origin-Destination) table. For the purpose of proper road network planning and controls, it is very important to quantify the traffic distribution on a road network. Currently the most widely used approaches can be roughly divided into two types: the static traffic assignment models and the dynamic traffic simulation models, either macroscopic or microscopic ones. However, the traditional models demands very detailed OD information, with inevitable complicated, black-box type of algorithms. As the result, the users often reach to the outputs without knowing the underlying logic behind. The traditional models are all link oriented, except the microscopic analysis, intersections play a trivial role (if any) in the traditional models, despite the fact that intersections rather than basic sections of road links, decide the performance of urban road networks in modern cities. In this paper we assume the passing probability of an intersection equals to the utilization of the intersection in the routes between OD pairs within a road network. Under this assumption, an explicit analytical model is developed to describe the distribution of traffic within a grid network by a single pair of OD, firstly a discrete model and followed by a continuous model that can be subjected to the method of integral in the future. Finally we use a proved commercial simulation model to validate the proposed approach. Our approach can be regarded as a simplified estimation method of traffic distribution and this work is also helpful for the researches on the road network density. Through our research we do not consider about the influence of congestion since our objective is limited to the planning stage only.

Emission is one of the important measures of effectiveness (MOEs) when developing traffic signal control setting. Alleviating emission burden through traffic signal control is cost-effective compared with other environment-friendly measures. This paper aims to investigate cycle length optimization at isolated signalized intersections from the viewpoint of emission. First, emission can be divided into four parts in terms of contributions of vehicle's cruise, idle, deceleration and acceleration modes. Second, emission from the whole intersection is modeled as a function of cycle length, and the cycle length minimizing emission is identified as C_emission. Then its characteristics is investigated and compared with the delay based cycle length. Finally C_emission is recommended to be applied on conditions with high cruise speed or high heavy vehicle percentage.

Multi-through lanes have been used to reduce vehicle delays and queue lengths at signalized intersections with relatively high through movement demands. Limited research has been conducted to study the through lane group capacity issues and how they relate to the number of lanes in the through lane groups. This study analyzed the influence of the number of lanes in the through lane group using 11 sites in Beijing. The one-way analysis of variance (ANOVA) test was used to determine statistical significance of the number of lanes' influence on saturation flow rates. In addition, regression analysis was conducted to determine the relationship between the number of lanes in the through lane group and the saturation flow rates. The results showed that the influence of the number of lanes in the through lane group on saturation flow rate was remarkable in Beijing. The relationship between saturation flow rate and the number of lanes in the through lane group was a quadratic function. At the end of paper, the default value of saturation flow rate and the adjustment factor for the number of lanes in the through lane group was given based on the traffic conditions in Beijing.

Sight distance and vehicle speed are closely related to traffic safety, and good sight distance not only enable driver to judge the road traffic environment correctly, determine the correct driving behavior, but also determines effective operating time of the driving behavior. This paper made an in-depth analysis to intersection sight distance and turning characteristics, and carried on a statistical analysis to relationships among stopping distance, landscape static sight distance and the difference between them with vehicle speed, which took Mudanyuan Intersection of Haidian District in Beijing as an example and used mathematical models of the landscape static sight distance and the stopping distance. From the experiments we find that intersection sight distance have a strong correlation with vehicle velocity. Intersection static sight distance and sight distance difference have positive correlations with turning right vehicle velocity, while have negative correlations with direct vehicle velocity. Besides, it can be seen by combining the existing data that the greater static sight distance and sight distance difference are, the higher the maximum speed which is allowed and enable ensure the safety of traveling and turning right vehicle velocity are, but direct vehicle speed is lower, which has certain relations with driver psychology. Direct driving in the situation of smaller static sight distance and sight distance difference, drivers will be more anxious and then they are more inclined to speed up to avoid transportation conflicts and accidents; but if static sight distance and sight distance difference are greater, drivers will control accelerator and brake calmly, and the moving velocity will be lower.

The objective and subjective factors affecting intersection safety is analyzed and the amount of weighted conflict points in a certain potential conflict area is selected as the intersection safety index. The intersection safety evaluation method is established with other affecting factors correction, such as geometric design, safety facilities. The rationality of the method is validated to show that it can analyze the intersection safety conveniently which needn't the traffic accident statistical data and traffic conflict survey.

In the past important differences have been found in the saturation flows in China and The Netherlands. Chinese saturation flow rates appeared to be 20 to 30% lower than the ones in The Netherlands. In order to confirm these conclusions, the methods for the estimation of saturation flow rates and other characteristics of flows at signalized intersections are compared. The regression method appears to give the most informative results, while headways give very detailed information but don't give an unbiased estimation of the saturation flow rate. The third method, the product limit method, uses also the information of unsaturated flow conditions and can give a direct estimation of the probability distribution of saturation flow rates and other characteristics.

The control program design of overlap phasing was studied for the non-equilibrium traffic flow at a signalized intersection. One approximate and simple method for signal timing of overlap phasing was presented. The application principles and conditions of overlap phasing were discussed starting from its concept. The design and timing methods of overlap phasing were constructed on the basis of the timing method of conventional signal phases. The application of the method was illustrated. The result showed that overlap phasing reduced total flow ratio, cycle, delay, and increased capacity. The research provided a theoretical basis for the design of overlap phasing. The effectiveness of time-space resources utilization and service level can be improved at intersections using the research approach.

This paper addresses two issues regarding arterial signal coordination and traffic progression: 1) It presents a sensitivity analysis of determining the optimal network cycle length under various combined options chosen among increment in cycle length, whether and how to allow uncoordinated, and ways to conduct offset optimization; and 2) It compares the effectiveness of three different network partition techniques which can be potentially incorporated into software packages. A case study is undertaken using a real world arterial in the City of Tyler, Texas. Numerical results indicate that using the Quick Offset Optimization command during the process of optimizing cycle length may not be sufficient enough to find the best signal timing plans and this is particularly true if intersections are allowed uncoordinated to a certain extent (ranging from Rarely, to Sometime, to Often). It is also found that the three different partition techniques (i.e., Coupling Index, Strength of Attraction, and Coordinatability Factor) differ only slightly and can produce the same solutions in all scenarios.

To realize the traffic control at the crossroads is by the red and green signal lights. In order to improve capacity of intersection, the green wave band is a useful signal control mode. This paper proposes a new kind of green waves display and control mode. There are signal lights along the road form the moving light zones, and the moving speed and length of light zones are determined and made coordinative of the signal cycle of intersection by the computer system. The driver can adjust his speed in time to join the green light zone, remain consistent with the speed of light moving and will pass the next intersection without waiting.

Pelem Gurih Junction is situated in Yogyakarta, Indonesia. This three arm signalized junction is very congested during peak hour. Therefore, it is planned to be modified into signalized roundabout. A computer simulation program: KREISIG (Kreisverkehrsplaetze mit Lichtsignalanlage=signalized roundabout), which was developed by Munawar (1994) in Germany has been employed to optimize the signal. This program can calculate the queues and delays at signalized roundabout. However, this KREISIG program is based on the German driver behavior, which is quite different from Indonesian driver behavior. Therefore, the sensitivity parameters and the yellow time decision of the drivers should be calibrated first. The saturation flow output has also been compared to 1997 Indonesian Highway Capacity Manual. Trial and error method has been employed to adjust the saturation flow. Turbine method has been used for signal setting. Then, the KREISIG program was run to optimize the signal setting. This program has been succeeded to optimize signal setting at this planned signalized roundabout.

Ramp congestion significantly hampered travel efficiency into urban expressways; about 30% of the total travel time is taken waiting at the expressway entrance during rush hours. This study is specifically concerned with ramps and an adjacent intersection, area traffic flow characteristics are analyzed, and the dynamic traffic flow equilibrium model is discussed with the objective to maximize travel capacity. Compared to a standalone approach, coordinated on-ramp and adjacent intersection control is presented, which has the advantage that cycle and phase information of upstream traffic signal can be used in the algorithms for ramp metering optimization. In analysis of the basic difficulties and limitations of theoretical models as well as continuous or interrupted traffic flow model during the practical application, innovative algorithm solving steps based on corridor traffic state is also discussed. With the model calculation results, a collaborative optimization control method to enhance capacity and alleviate congestion is applied to ramp metering and signal timing. Mostly, as a demonstration project of Shanghai expo ITS integrated system, a traffic flow model and coordinated control strategy are applied to the case of West Yan'an road with one adjacent on-ramp. A simulation study was conducted to compare on-ramp control performance between coordinated and a standalone approaches. The optimization control parameters are computed, and the simulation evaluation results show that with the coordinated control, traffic capacity increases by 18.63%, and the vehicle delay decreases by 21.3%.

The operational condition of traffic flow and capacity of a signalized intersection to some extent depends on the setting of signals; the better the signal timing, the greater the capacity of intersections. This paper analyzed the survey data of Wuyi Road-Southwest Road intersection, Dalian, calculated the current capacity and delays of the intersection, then re-organized traffic flow according to the practical traffic demand and designed an unsymmetrical five-phase signal timing scheme based on the principle of overlap phase. The calculation showed that using the improved signal timing scheme, it will result in a moderate increase in traffic capacity (21.9%) and an significant decrease of delays (53.1%).

In urban traffic systems, intersections are often to be capacity bottlenecks and high accident locations. T- intersections are generally less efficient than standard four-leg intersections. This paper addresses the traffic conflicts of T- intersections and introduces the traffic signal phases that could improve the efficiency of T-intersections. According to the general signal timing methodology for intersections, an improved method for T- intersections was introduced. Through a case study, the improved method proves to be more suitable for T- intersection signal settings and has a high practical value.

Bus-stop is one important compositions of urban traffic system and often produces some traffic interruptions since the buses should stop at the bus stop. In urban traffic system, there are often multi bus stops on a road, so the distance between bus stops will have great effects on traffic flow and produce some complex traffic phenomena. In this paper, we use the traffic flow model to further study the properties of the traffic flow on a ring road with two bus stops. The numerical tests show that our model can describe the effects of the distance between two adjacent bus stops on the stability of traffic flow and reproduce some complex traffic phenomena under the action of difference distances, which just show that our model is reasonable.

Traffic stream models provide relationship among the three basic macroscopic traffic stream characteristics namely traffic speed, volume and density. Traffic stream models are the basic building blocks of traffic flow modeling, design of road systems and traffic management systems. A number of research papers are available proposing different traffic stream models. However, majority of them are based on homogeneous traffic conditions and they may not be directly suitable for the Indian traffic condition. Not much research has been done on this important aspect so far in India. The present study is an attempt to develop a traffic stream model suitable for the heterogeneous traffic flow condition, such as the one existing in India, taking Chennai as case study. Traffic data for the present study are collected using video graphic technique. Flow, speed and occupancy are manually extracted from collected videos and density estimated using the relation connecting occupancy and density. The results show an exponential speed-density relation and parabolic relations for the other two.

In the urban traffic network, concurrent traffic congestions are serious problems. They usually occur in fixed positions called bottlenecks. They are sources of the traffic congestions which influence the efficiency of the traffic network. Therefore the first step to improve the transport performance is identifying the traffic bottlenecks. This paper presents a novel two-phase method to identify the traffic bottlenecks in urban road network and analyzes their effect. The method presented in this paper integrates both urban planning and actual traffic flow. In 1^st phase, the initial possible areas containing bottlenecks are determined. We use urban planning data to determine the reliability of the traffic network and the scope of possible traffic bottlenecks based on fuzzy c-means (FCM) algorithm. Then, in 2^nd phase, we use the bottleneck index denoting the match degree between actual traffic data and the network physical attributes to identify the exact bottleneck positions. Finally, we test the effectiveness of two-phase method using an actual urban traffic network. The chosen road network based on network in Jilin, China is built up by Paramics Software according to the actual data obtained from Jilin Traffic Management bureau and Jilin Construction Commission. The simulation results perform in accordance with the practical situation, which can verify the applicability and feasibility of the proposed method.

Travel time reliability is one of the parameters that evaluating the quality of traffic service in urban road network. The paper suggests a new method of area traffic control evaluation based on the travel time reliability. First, the concept of travel time reliability is defined and the travel time reliability model is built. Subsequently, the paper emphasizes on establishing the area traffic control evaluation model, which is based on the travel time reliability. The demonstration and utilization of evaluating the area traffic control system illustrates that the new method proposed in this paper is feasible and efficient.

Aimed at the hot topic "vehicle restriction in Beijing," this paper set up a systematic monitoring and evaluation system. Firstly, this paper reviewed the experience and effectiveness of the implementation of TDM in the world, particularly Mexico City's implementation of a 10-year-old motor vehicle restriction measure. On this basis, according to Beijing's vehicle restriction multiple effects, this paper established a set of comprehensive evaluation systems including traffic, environmental, and social impact. Through the methods of floating car systems, congestion evaluation indices, public transportation IC cards, public opinion surveys, and web-based surveys, systematic data were analyzed. The data shows that the traffic and air quality has improved, especially the traffic congestion The public strongly supports all improvement within the traffic system. This paper will provide an important reference for decision-making and other cities' traffic management research and implementation.

Urban expressway is a rapid arterial that connects main areas of the city, and meets the great-amount, long-distance, and high-speed demand of urban traffic. The friction coefficient of roads covered with snow and ice is reduced, and the traffic operation risk is increased in regions with high latitudes, whose winter is long and cold, and those conditions led to the reduction of road capacity and the increase of traffic delays. Using the video detection device, one of the traffic flow information collecting devices, a large number of data in the period of ice and snow of cold area are collected, which is the research base of this paper. The macro and micro traffic flow characteristic of urban expressway under conditions of the snow and ice environment are analyzed, such as the instant traffic flow, the distribution of headway time, and the properties of the speed distribution. The relation models of speed-volume are built. At the same time, the traffic flow characteristic of the urban expressway in the period of ice and snow of cold areas are compared with that of non-snow periods. The outcomes studied above are the foundation for analyzing traffic operation and capacity of urban expressway in the period of ice and snow.

The traffic congestion can aggravate the system function and the network efficiency, which leads to the decrease of traffic system performance. Therefore, the performance evaluation for traffic networks (e.g., railway and road) has extremely important practical significance in the transportation planning and management. Here, we analyze the performance in the scale-free network generated by Molloy-Reed algorithm. We compare two important network performance evaluation methods with the consideration of traffic congestion and structural efficiency respectively. A significant finding is that only congestion or efficiency is not accurate to evaluate the performance reasonably. In order to avoid shortcomings and find a remarkably compromise between the congestion and efficiency, we propose a combined model with the consideration of them. Additionally, the effect of weighted parameter on the performance of traffic system is investigated.

This paper quantitatively analyzes the effect of road section crosswalks on urban road capacity and the running characteristics of pedestrians, bicycles, and electric bicycles when they pass through a crosswalk were also studied. The equivalent people group was also defined to describe the common effects of pedestrians, bicycles, and electric bicycles on vehicles' running. Taking sample stability and application convenience into consideration, an analysis period of 15 minutes was adopted. Then, by means of statistical analysis, the values of equivalent people number, average equivalent people groups' time headway, and equivalent people groups' number of each 15 minutes were obtained. By means of a regression analysis, the 11 kinds of regression models between 15 minutes equivalent people number and average equivalent people groups' time headway, and the 11 kinds of regression models between 15 minutes equivalent people number and equivalent people groups' number were obtained. Based on the correlation coefficient values and application convenience, the inverse function was adopted to describe the relationship between equivalent people number and average equivalent people groups' time headway, and the cubic function was adopted to describe the relationship between equivalent people number and equivalent people groups' number. And then, the method of time resource occupancy was adopted to analyze the effect of pedestrians, bicycles, and electric bicycles on urban road capacity, and the adjustment factors under the condition of whether there is a signal for pedestrians to pass through a crosswalk were obtained. Research indicates that the average equivalent people groups' time headway decreases with the increase of equivalent people number, and the equivalent people groups' number firstly increases and then decreases with the increase of equivalent people number. Case study indicates that when the traffic volume of pedestrians, bicycles, and electric bicycles is relatively high, signal control can effectively reduce the impact of road section crosswalks on urban road capacity.

This paper studies the effects of speed difference on the real capacity of freeway, based on the speed difference definition of Average Speed Difference. It is found that there is no obvious relationship between speed difference and the real capacity under high level of service, while under medium and low level of service the real capacity is lower than the potential capacity on the effects of speed difference. Based on the analysis of safe car-following behaviors, the relations between vehicle speed, space headway and speed difference are established, from which the modifying factor of real capacity due to effects of speed difference is derived. Compared with existent models, the model presented in this paper is more understood theoretically, and it is able to describe the effects of speed difference on the freeway capacity under various levels of service.

A large number of facts have shown that emergency of congested links in urban traffic network has certain rule. This rule will help us to identify characteristics of the generation, propagation and dissipation of traffic congestion, which can provide some theoretical foundations for the development of reasonable traffic planning and control methods. In this paper, based on the cell transmission model (CTM), a model is proposed to analyze the propagation of traffic flow. The spatial autocorrelation method (SAM) is introduced to analysis the spatial distribution characteristics of congested links by using the average journey velocity (AJV) of links. Numerical results show that the traffic congestion appearance among adjacent or close links is interrelated, and with the increase of traffic demand, this relationship will become more and more obvious.

Traditionally, the evaluation of the road improvement project is mainly based on the indexes of V/C ratio and travel speed, aiming at improving the traffic performance (Chen, 2002). However, the improvement can guarantee neither the decrease of the spatiotemporal cost of single vehicle, nor the increase of the transportation efficiency. The evaluation is typically a problem of multi-input and multi-output, on which the traditional method fails to create the connection among all the inputs and the traffic performance, and the results selection is apt to be affected by subjective factors. Based on efficiency analysis theory, using data envelopment analysis, this paper builds a CCR model to evaluate an alternative scheme and to analyze and diagnose the ineffective scheme. This paper adopts the popular HCM analysis method and analyzes fluctuation of the index with time and exterior operation conditions (National Research Council, 2000). Results show that travel delay is more appropriate as the traffic operation index in the complex roadway environment. Moreover, approximate calculation methods of this index are discussed.

This paper presents an algorithm based on Dijkstra's algorithm and the distributed Bellman-Ford algorithm (DBF) for path planning in transportation systems, where distributed algorithms are needed to work along with Wireless Sensor Networks. In our algorithm, each node in the network runs Dijkstra's algorithm on the topology it perceived, which we distinguish from the whole topology by giving the name the perceived map, to construct its shortest-path tree, and through exchanging messages with its neighbors it can renew the perceived map. As every node keeps receiving messages for a predefined time and link-costs in a traffic environment often vary moderately, this algorithm can perform well when more than one link changes its cost at the same time.

How to provide a route to meet the driver's multiple psychological expectations is the key problem of a navigation system. Essentially, this problem is a resource constrained shortest path problem (RCSP), which belongs to NP hard problems and can not be solved with the traditional shortest path algorithm. A multi-constrained shortest path mathematical model is presented in this paper and solved with an improved ant colony algorithm. The pheromone update rule and heuristic factor are redesigned in the algorithm. Results show that the improved optimization algorithm has a good ability to accurately determine the multi-constrained shortest path in the road network.

As an important measure of traffic demand management, congestion pricing can guide and regulate traffic flow to achieve the purpose of easing the traffic congestion. Therefore, it has been paid more and more attention of scholars. Congestion pricing methods are the core and foundation of congestion pricing theory, and the rationality of the pricing model is directly related to the scientific congestion pricing strategies. In the traditional congestion pricing model, it doesn't correspond to reality, if a traveler is assumed absolutely rational, but the decision-making process can be exactly described by the cumulative prospect theory in the uncertain situation, and it is consistent with the bounded rationality of traveler character. In this paper, on the basis of cumulative prospect theory and Wardrop user equilibrium principle, the psychological effect factors of travelers are brought into the congestion pricing model that well overcome the defects of the traditional pricing model, analyses and prove the feasibility of the model at the same time.

This study is part of an effort to incorporate road user costs and economic impacts into the current asset management system in the network level pavement rehabilitation decision-making process. MicroBENCOST and HDM-4 (Highway Development and Management Model), which are widely used in the road user cost estimation process in North America, are used to calculate user costs, benefits and benefit-cost ratio and results are evaluated. The outputs generated from the two programs are analyzed and compared when the input conditions are consistent for both programs. Several critical input parameters which have a significant influence on the major outputs are identified. In addition, two statistical correlation models based on the outputs of the two programs, which provide a simple and fast way to calculate user benefits, are developed.

Taking advantage of a genetic algorithm based bi-level programming solution to find the optimal scheme for second-best road pricing. The highlight of the work is a case study using the actual Nagoya metropolitan area road network instead of a numerical network. The effectiveness of the method is evaluated for this network by comparing 3 cordon pricing schemes with optimal tolled schemes having the same number of links. The results show that under a situation with the same number of links, the scheme using optimal toll points works better than the cordon pricing scheme.

In this paper, survey data of students' travel modes from both parents and students were collected at 18 schools (16 elementary and 2 middle schools) in Pinellas County, Florida. A new diagnosis approach was used to pin down the factors significantly affecting students' travel modes. Multi-perspective diagnosis results identified different factors that significantly affect the walking/biking rate for different groups of students. Generally, students living in different distance intervals are subject to different barriers. Security and safety are the primary factors of concern for short distance interval people, while distance is the primary factor of concern for those who live farther away from the school. The multi-perspectives diagnosis proved to be an effective method to mathematically search for the necessary-sufficient condition for increasing students' walking/biking rate.

Using the travel-activity data collected from Shangyu, China, this paper develops multinomial Logit model with aggregate alternatives, including multiple size variables in representation for intermediate stop destination choices in the commute activity patterns. We use the amounts of facilities with different land use in the surveyed destinations as the size variables. Apart from the zonal attractions (size variables), locational factors and OD matching characteristics, Hanson accessibility are introduced into the models. The empirical results show that the commercial establishments are most likely to be chosen by intermediate stopping. And CBD area offers more opportunity to the intermediate stops. Moreover, the results show that the destination containing maintenance/leisure places compete with those nearby to win more intermediate stopping opportunity, which makes it more attractive in Shangyu, China. The findings of this paper provide some useful insights into the spatial activity-travel behaviors in the context of China.

The way of providing information for reducing disaster damage has been more important in Japan. By providing appropriate information to citizens under downpour, citizens can understand disaster situation and behave appropriately. Therefore, this paper focuses on the use of privately owned cars under downpour which is often brought up the deteriorating factor of traffic jam under downpour, and examines the way of providing traffic & weather information for reducing car use under downpour through the development of behavior model of returning home and other analyses. As a result, it found that the effect factor to driver consciousness of returning home under downpour.

With the advent of Leisure Economy Times and the popularization of cars, besides being used for daily commute and business travel, private cars are playing an important role in recreational activities on weekends and holidays, which is called urban self-driving tourism in China. To understand the behavioral characteristics of this type of tourists, we carried out a survey in Kunming, Yunnan Province, China. We found that it is the individual values and the life style rather than normal travel factors that were the determinants in self-driving tourism. Both travel purpose and travel radius were strong features of recreation. The destinations were generally within ReBAM (Recreational Belt around Metropolis) which was about 500km around the city. The travel distance had the "anti-attenuation" phenomenon. Concerns on transportation, safety and information were the three main discouragements to self-driving tourism.

This paper surveys the travel behavior of bus-use commuters in Yangon, Myanmar and analyzes the bus route-choice models with the collected data. The revealed preference survey combined with the stated-preference survey was implemented in the western and southern parts of Yangon City. 1,240 choice data of 169 individuals were collected including 169 RP choice data and 1,080 SP choice data. Then, the bus route-choice is analyzed with a binary Logit model. After checking the reliability of SP data by estimating the SP model, the RP/SP combined model is estimated. Additionally, the RP/SP model incorporating the monthly income is also estimated. They show that the bus-use commuters prefer the high-quality buses to the truck bus. They also show that the estimated value of travel time is about 10.1 Kyats/minute and it increase as the monthly income increases.

In order to study the law of inhabitant travel time distribution, the model for the constraints of utilities and targeted information entropy maximization was proposed. Probability theory of Logit model and maximum information entropy principles were used to build the planning model. Through solution of the planning model, model of inhabitant travel time distribution was set up. The frequency distribution of travel time of work, school, and shopping about Suzhou City has respectively 2,3,4, and 5 polynomials simulated, and suggests using 4 or 5 times the polynomial to simulate travel time distribution. The results of simulations show that travel time distribution of work, school, shopping are accord with the model.

There are over 18,500 children below the age of 14 that died from traffic accidents every year in China. The death rate in China is 2.5 times more than that in Europe and 2.6 times compared to the USA. Researchers have shown that half of children's traffic accidents were caused by their own negligence. One of countermeasures is to enhance the children's traffic cognition which can not only reduce the traffic accidents in childhood, but also help them become good drivers when they grow up, and therefore improve the traffic system of the society. This article designed a questionnaire of child pedestrian's traffic knowledge, cognition, behavior, and attitude from them and their parents which suits for a developing country's city—Kunming (in China). Based on the data from 122 primary school-aged children of the city, the child pedestrian's traffic cognition and behaviors were analyzed by statistics including Pearson, Spearman's rho and Kendall's rank correlation. The results showed that there was a considerable difference between the child pedestrian's traffic cognition and behaviors (r=0.805, p =0.005), and a significant correlation between children and parents behaviors (Kendall: rk=0.079, P=0.032; Spearman: rs=0.086, P=0.038). Due to the weakness in the traffic safety education from parents, school, and government for child pedestrians, some feasible educational and practical measures on educating children's traffic safety were put forward for cities in developing countries.

The information collected by probe vehicles on the urban signalized network is widely used for traffic monitoring. Traffic conditions could be inferred based on the data collected by these probe vehicles. In recent years, the attempts to estimate link travel time based on probe vehicle data (e.g. positions, time stamps and speeds) are arising. However, due to the low polling frequencies (e.g. 1min or 5min), travel times recorded by probe vehicles provide only partial link or route travel times. In this paper, a three-layer Artificial Neural Network (ANN) model is proposed to estimate the complete link travel time for each individual probe vehicle. The information including positions, time stamps and speeds is input into the model and the output is the complete link travel time. The model is evaluated using the data from vissim simulation model. The results are compared with those from Hellinga's model and distance-proportion model. The evaluation results show that the proposed ANN model performs much better than Hellinga's model and distance-proportion model both in undersaturated conditions and oversaturated conditions.

This paper discusses possible countermeasures for traffic accidents involving university students using mopeds, based on recent research findings. The first part of this paper is a review of research about traffic accidents involving mopeds. Second, we show the importance of decreasing the encounter of mopeds with large-sized vehicles in order to decrease the number of accidents, in particular the number of fatalities caused by these accidents, based on a macroscopic statistical analysis of Japanese traffic accidents classified by vehicle types. In the last part of our paper, we argue for the necessity of a time dimensional transport demand management on campus as one possible and effective way to reduce encounters between mopeds and heavy vehicles.

This paper forecasts the future trade amount and international cargo flow, especially focused in China, using by the stepwise trade amount and international logistics flow forecasting system in East Asia that the author had been developed. For the trade forecasting sub-model, the Global Trade Analysis Project (GTAP) model, the most famous model to predict world's trade amount applying Spatial Computable General Equilibrium (SCGE) model, is applied after a few modifications. A future scenario is prepared on the future economic direction based on interview survey to many experts, including advancement of economic cooperation such as FTA. For the international cargo flow forecasting sub-model, the original model developed by the authors in order to reproduce international logistics flow on multimode transport network in East Asia including road, land, and ferry transport as well as international maritime shipping is applied, where cargo transport demand (i.e. OD cargo volume) between regions are given. In the future simulation using this sub-model, the future investment plan of the transport infrastructure such as new container terminal construction in Chinese ports should be considered. Furthermore, by comparing the calculation result without any consideration of these policies, the effect of these policies can be quantitatively measured in terms of transport cost reduction.

Rising levels of affluence, living standards and diversity of lifestyles result in rising expectations on the performance of the road transport sector. The Vehicle Quota Scheme and Electronic Road Pricing remain the cornerstones of Singapore's transport policy towards private transport. Few drivers however, are drawn to public transport. This study adopts the behavioural approach to explore possible solutions to smoothing the peak-hour travel by focusing on time-based differential pricing. We propose the introduction of staggered concessions for peak hours as commuters have different values of time. This implies that some are willing to pay more without changing travelling habits while others would take advantage of a concession and travel off-pea. However, the concession scheme would have an even greater impact if flexible working hours is introduced. This is drawn from the observation that a higher concession rate would tend to have a bigger variance in deviation. A lower concession rate is less attractive and few people would be enticed. A concession rate 5 times as large would be deemed as being significant and more than five times the amount of people would be enticed to change trip departure decisions.

Traffic modal splitting plays an important role in the traditional four-stages-forecast model. Usually in a stable urban traffic network, traffic supply can meet the demand basically, and a variety of traffic modal will bear a fixed proportion of passengers. Compared with other trip mode, public transportation is often influenced by some uncertain factors, e.g. transferring and waiting, which will cause different marginal cost and finally come to a new balance or imbalance between demand and supply. In this paper, traffic modal was supposed as a rational gamer, and generalized trip cost was considered as the cost of gamer. Then, traffic mode share can finally be got via comparing supply of all kinds of traffic means. A case study is conducted and compared with disaggregate modal, which shows the game theory-based model is more effective and the outcome is closer to the real traffic modal share.

It is a matter of utmost importance to predict dangers accurately in advance and to prevent accidents from occurring for a ship, which is navigating on the sea. Based on analyzing the cases of a shipwreck which have occurred so far, we discovered that more than 80% of the accidents were caused by wrong instructions issued by the captain of a ship. Especially in severe weather or in an emergency, inaccurate instructions have caused fatal damages. Based on machine learning, a method for analyzing and assessing the operation instructions sent from the bridge is discussed in this paper. ID3 algorithm is applied to build up an assessing decision tree, which can be improved and modified in the course of practical application. Operation instructions can be analyzed and accessed using this decision tree. The objective is to prevent the accidents caused by false instructions, and hence the safety and security of a ship navigating on the sea will be improved.

Travel mode choice can be regarded essentially as a problem of pattern recognition. In the past, numerous researchers applied artificial neural network (ANN) to travel mode choice modelling. Feed-forward back propagation neural network (BPNN) is widely used, and most of the studies show that BPNN presents better prediction accuracy and generalization capacity. Probabilistic neural network (PNN) is also known as a general solution to pattern classification problems by following an approach developed in statistics. Comparing to BPNN, its shorter training time and better stability increase the reliability of simulation results, even so PNN is barely used in travel behaviour analysis. Therefore the paper tries to apply PNN for travel mode choice modelling. First, network structure is established based on the data obtained from resident trip survey, and then the K-means cluster algorithm is applied to optimize the hidden node number so that they can be modified dynamically. Moreover, the data centers and extended constants of gaussian radial basis function are changed adaptively during the learning progress, and the improved PNN is called KPNN. To reveal the superiority of KPNN, BPNN is also introduced to make a comparison. For BPNN, the optimal number of hidden nodes is recognized, and then the well trained network is applied. By proposing two performance measures, the classification and predictive capability of KPNN and BPNN is evaluated, it is found that KPNN outperforms BPNN on both the simplicity and prediction accuracy. Anyway, the simulation results show that KPNN can deal with the problem of travel choice modelling as well as, if not better than BPNN.

The urban passenger transport system plays a key role in providing services for passengers. By combining a science system with complex network theory, we analyze the relationship among various actors of the urban passenger transport system, which is a network model consisting of managers, companies, passengers, and their interactions. The structural and dynamic property of the urban passenger transport system is described. Through analyzing the network's nodes and structural edges, the network dynamic evolution model can be established. The Harbin taxi passenger service market system was studied as an example to simulate and validate a proposed model, which reflects the objective laws of the urban passenger transport system and provides a new way to investigate the urban passenger transport system.

Data envelopment analysis(DEA) is an optimization-based technique widely used to measure relative efficiencies of public transit agencies. This paper evaluates the performance of bus routes within a public transit system using the BCC model of DEA. We construct a concept framework of performance evaluation and select appropriate input and output indexes to compute the operation efficiency and service effectiveness of each bus route. Function-achievement is then analyzed and bus routes which need to be optimized and regulated are screened out. Twelve bus routes of Suzhou are selected for the practical application.

This paper addresses the problem of creating a combination bus timetable for a given bus network with multi-routes so as to minimize the waiting time of non-transfer passenger and transfer passenger. It attempts to arrange the departure time of the bus in any route to satisfy the demand of passenger with minimum waiting time, and enables the transfer passenger from one route to another with minimum waiting time at the transfer station. In this paper, the problem is formulated as a nonlinear programming problem, and the departure time of each bus in any route is the decision variable. This problem is solved by particle swarm optimization (PSO). The computational results presented in this paper show that the optimization method presented in this paper can create a multi-routes combination bus timetable, which satisfy the passenger demands, to minimize the waiting time. A comparison between traditional timetable and combination timetable shows that combination timetable can perform better satisfying the mutative passenger demands and reduce more waiting time.

To aim at maximizing utilization of vehicles, this paper discusses how to spend a limited budget to buy different types of buses to cover all assigned trips for bus scheduling to meet some requirements such as fuel restrictions, depot capacities, and an upper limit for air pollutants emitted from these buses. The mathematical model is formulated in a form of the integer programming problem in "Block Based" formulation ways, and solutions are obtained using the ant colony optimization (ACO) which uses new heuristic information and redesign a feasible solution construction according to the features of bus scheduling. Finally, numerical computations show that ACO can find good solutions effectively and efficiently.

The earthquake happened in Wenchuan, Sichuan, province on May 12, 2008, resulted in a tremendous loss of property and lives. Emergency evacuation and transfer are so important that government should give them high priority. The emergency evacuation corridor planning will be more significant for restoration of disaster areas. This paper proposes a methodology for the carrying capability of regional earthquake evacuation corridors based on macro-simulation and to prove the availability and rationality of a predetermined regional earthquake evacuation plan. The proposed approach includes three processes: 1) Estimate the evacuation demand of earthquake affected area; 2) Confirm the OD-pairs based on the location of shelter and the preplanned direction of evacuation; 3) Build up the earthquake evacuation network through the macro-simulation software OREMS as well as input the outcome of procedures 1 and 2. Meanwhile, the carrying capability of preplanned regional earthquake evacuation corridor through evacuation clearance time and average evacuation speed are the output of OREMS. In the end, the proposed approach was employed in the Beijing case and proved the availability and rationality of Beijing earthquake evacuation corridor planning. Criterion for selecting the earthquake evacuation road and the methodology for searching availability and rationality of earthquake evacuation corridor planning are proposed in this paper.

The objective of the research was to develop an advanced traveler information system framework that supported individual requirement for travelers. Advanced traveler information system is related to comprehensive sources and diversified forms of traffic data distributed in heterogeneous systems. The difficulty of data integration of heterogeneous systems demands a proper method to solve the problem. Due to SOA's contribution to the integration of heterogeneous systems, the paper focuses on the designing and implementation of SOA-based traveler information system. This system uses a Service Oriented Architecture (SOA) that contains four roles. These include: a service registry, an integrating platform, service requesters and service providers. Then four key technologies are proposed, including requirement identification, service matching, service composition and service delivery. Furthermore, the paper describes the process of the system and a way of realizing the system by the application of Web Service. Finally, we implement a traveler information system for the city of Beijing. It uses the Web service technology to encapsulate real-time traffic service, route planning service and map inquiry service; then a new service is composed of real-time traffic data and route planning data by applying service composition algorithm. The result is displayed with a GIS map on mobile software. The architecture of this system not only improves the efficiency of system interoperability, but also provides a platform that can effectively realize service integration when needed. Therefore, it is an appropriate way of designing a traveler information system.

Mobile traffic sensor data, once widely available, will significantly enhance current transportation modeling applications such as arterial performance measurement. Receiving and processing mobile sensor data however may involve severe privacy concerns if not properly designed. In contrast to the fact that the current research on transportation modeling and privacy protection is rather separated, we propose in this paper a framework on privacy-aware transportation modeling (PATM) and application-aware privacy protection (AAPP). The proposed framework focuses on the interactions between transportation modeling and privacy preserving, being aware of privacy when developing transportation models as well as application needs when designing privacy preserving mechanisms. Using two case studies, we show how PATM and AAPP may be applied in privacy-preserving mobile data collection while satisfying the application needs at the same time. The paper is concluded by discussing how to design a unified approach to guarantee privacy and data needs for various applications.

Passive GPS travel survey has proven an innovative alternative to the traditional paper-and-pencil method, as it can record exact time and location of travel activities without incurring much burden on survey respondents. Lying in the core of this technique is how to derive accurate travel information (e.g., trip purpose) from GPS data. Previous studies rely on simple rules that are manually extracted from the inherent structure of GPS data streams. These methods, however, are difficult to generalize for other applications and lack helpful hints for new research. This paper presents a machine learning approach to deriving trip purpose from GPS track data coupled with other relevant data sources. This approach employs a number of attributes (i.e., time stamp and land-use type of trip ends, a set of spatiotemporal indices of travel, and demographic and socioeconomic characteristics of respondents) to construct a decision tree for purpose of classification. Each attribute provides partial evidence to the depiction of a given purpose, but this depiction may or may not be monotonic, and none of them can work alone toward the goal. A reasoning procedure using the adaptive boosting technique was designed to explore how these attributes could work together to achieve trip purpose derivation. This technique generated multiple decision trees to improve the classification results through a mechanism of voting from these trees. Each tree was constructed in the depth-first fashion with the root node and the split of subsequent nodes being determined on the basis of the gain-ratio computed for the relevant attributes. This procedure was implemented in the C5.0 machine learning environment with 226 GPS trip records collected from 36 respondents. The experimental results seemed rather promising: using 10 iterations for adaptive boosting, an overall classification accuracy of 87.6% was achieved.

In order to evaluate the freeway incident management systems, the normal travel time for calculating the incident delays and benefits usually needs to be predicted. The evaluation result is very sensitive to incident delay, so it is inaccurate to use month, week, or day average value for describing the normal travel time. The artificial neural network with strong adaptability and high accuracy was proposed to solve the problem. Firstly the structures of a predicting model and data acquisition plan were proposed. Then a genetic algorithm was introduced to improve the traditional BP(Back propagation) neural network considering that BP network easily falls into the local convergence, and the genetic algorithm has a good global search capability. GA-BP(Genetic algorithm improved back propagation) network showed better convergence speed and predicting accuracy than BP in the study of Ningtong freeway travel time. The final error of GA-BP can be accepted, and the forecast results meet the actual need.

In this paper, we report the preliminary results of the sensitivity test for California Production, Exchange and Consumption Allocation System (PECAS). The sensitivity test includes three scenarios: PECAS Only, Integrated, and High Travel Cost. The PECAS Only scenario allocates production and consumption at a fixed travel cost from years 2000 to 2020. It shows that the floorspace growth is more affected by general plan than travel cost, and residential floorspace types have higher growth rates in suburb, exurb and rural areas. Additionally, nonresidential (industrial and commercial) floorspace types have higher growth rates in the inner urban areas. The Integrated scenario has a more compact land use pattern than the PECAS Only scenario. Compared with the Integrated scenario, the High Travel Cost scenario leads to more compact use. The results from all three scenarios imply that the model behaves as expected and the outputs are consistent with what has been theorized.

This study focuses on the assessment of the congestion impacts of fatal accidents. The paper addresses the current paucity of research into accident induced congestion levels outside of Motorway/Freeway environments, and using the SCOOT traffic control system, provides an assessment of these impacts in more heterogeneous urban environments. Levels of induced congestion are found to vary significantly according to the temporal and spatial settings in which they occur, with only accidents that occur in either peak periods or constricted network layouts producing significant induced congestion externalities in monetary terms. The detailed spatial and temporal resolutions required for such forecasts are subsequently discussed, as these raise a number of issues for SCOOT and ITS data more generally, if such analyses are to become more detailed, sophisticated, and ultimately automated, across a range of complex temporal and spatial settings.

The real-time monitoring of vehicles' velocity has become essential for traffic safety. Therefore, in order to improve the method of monitoring the velocity of vehicles on road, this paper described a new radar velocity-measuring system, which is based on ARM processor. This system is based on the Doppler principle and spectral estimation algorithm in its hardware design part, and it takes full use of the underlying resources of ARM processor to achieve sample, digital signal processing and peripheral control in the separate ARM core. In the software design part, it analyzes the main program flow, at the same time, since the ARM processor does not support hardware floating-point operations, it puts forward the usage of fixed-point numbers to store and calculate floating-point numbers, which makes the data loading and storage minimization. It uses ARM assembly language to write the core algorithm and takes full advantage of the 5-stage pipeline of ARM processor to achieve the right register allocation and instruction scheduling for fine-grained control, and also to avoid the pipeline interlocks. Experimental results indicate that the accuracy of this velocity measurement system can reach ±1km/h. It not only can be used in traffic enforcement agencies, but is also low cost, low power consumption advantages.

The new method of capacity analysis at unsignalized intersections was developed in the authors' study for mixed traffic condition in developing countries (e.q. Indonesia) where the drivers' behavior, traffic composition, level of roadside activities, etc. were different from that of developed countries. The new method called "conflict technique "is based on the interactions between average speed and flow of conflict streams (six streams and six conflict points) considered. All possible conflict streams were considered simultaneously and the interactions were taken into account through empirical regression models. Six conflict groups (with six subject streams) were considered for all intersections to obtain the relationship between speed and flow of conflict streams. This phenomenon would measure a critical speed of traffic streams at the intersection when the capacity is reached. This method would measure any relationship between speed and flow of each stream of traffic and speed and flow within the group of conflict. The Method could provide a new technique to determine a critical speed of unsignalized intersection under mixed traffic flow where the capacity/maximum flow is reached.

The cellular automata model proposed by Tian and Jia, was established in the framework of Kerner's three-phase traffic theory and able to reproduce the three-phase traffic flow. But the first order transition from free flow to synchronized flow, which has been observed in the real traffic, could not reproduced in Tian and Jia model. One can see that the synchronized flow begin to emerge in Tian and Jia model, when the density is very low, which is obviously not in consistent with the real traffic. Therefore, we improved their model by the following main aspects. (i) The randomisation probability function and the deceleration extent in the new model have considered more situations according to the real traffic than that of Tian and Jia model. (ii) The slow-to-start rule in the new model is different with that of Tian and Jia model, since the slow-to-start rule in Tian and Jia model is not insistent with the real traffic. (iii) According to the new model, all vehicles will go through the randomisation step first according to its updated rules. Through these improvements, the new model can successfully reproduce the first order transition from free flow to synchronized flow, which is clearly shown on the fundamental diagram. Moreover, one can see the coexistence of the free flow and synchronized flow on the space-time plots, which is strong evidence of this transition. Then the 1-min average flux density diagram, the correlation functions are presented to identify the synchronized flow state. All results have shown that the new model is well consistent with the empirical findings.

The successful wide scale deployment of Advanced Traveler Information Systems (ATIS) and Advanced Traffic Management Systems (ATMS) relies significantly on the capability to perform accurate short-term predictions of traffic parameters over the entire road network. Most of previous studies and applications of traffic prediction have developed statistical or heuristic methods based on historical or realtime traffic data collected by fixed sensor networks. Meanwhile the effectiveness and wide applicability of such methods is strongly affected by the high cost of deploying and maintaining fixed sensor networks able to provide large spatial coverage. Recently, mobile sensors or probe vehicles appeared as a complementary solution to fixed sensors in order to increase coverage areas and prediction accuracy without requiring expensive infrastructure investments. The focus of this paper is to present findings of a study on short-term traffic prediction based on data collected by a probe vehicle system operating on the Italian national scale and consisting of a large fleet of privately-owned vehicles. Particularly the paper proposes and compares two models, respectively based on Artificial Neural Networks and Pattern-Matching techniques, designed to on-line perform short-term (15 to 60 minutes) predictions of link travel speeds. The Rome Ring Road (GRA - Grande Raccordo Anulare) is used to assess the feasibility of the two models. Testing results showed that the proposed approaches for short-term predictions are very promising and effective.

The accuracy of the urban short-term traffic flow prediction directly affects the realtime and reliability of the urban traffic control and management. To improve the accuracy and usefulness of the urban short-term traffic flow prediction, the Semi-variable Cell Transmission Model (SCTM) is proposed based on the cell transmission model. According to the traffic flow conservation, the cell length and the cell density are introduced into the SCTM, which overcomes the limit that the cell length must be uniform, in order to ensure the applicability and usefulness of the urban short-term traffic flow prediction based on the SCTM. Furthermore, the SCTM limits the scope of the cell length and sets the time interval to meet the requirement of the uniformity of the traffic distribution in the cells to improve the accuracy of the flow prediction. Finally, the SCTM is used to predict the short-term traffic flow in the urban road, and the predicted data are compared with the actual data. The analysis results indicate that the short-term traffic flow forecasting by the SCTM is satisfactory.

Space-mean speed is an important indicator of road network performance in traffic operations and management. To collect travel time and speed data, video detectors or loop detectors are usually deployed. However, most detectors, such as Autoscope Video Detection System, measure spot speed or time-mean speed directly but not the space-mean speed over a section of roadway. An approximation method, which is commonly used to estimate space-mean speeds, is based on the average speed of vehicles traveling on a given segment of roadway during a specified period of time. However, such segment of roadway and specified period of time (refer to spatial and temporal aggregations) have significant effects on the estimation of space-mean speed. This paper investigates the effects of spatial and temporal aggregations of Autoscope data on the estimation of space-mean speeds with different length of measurement sections (5m, 10m, 15m and 20m) and measurement time intervals (20s, 30s, 60s and 120s). The results show that the space-mean speed can be better estimated by Autoscope data using 10m measurement section with a time interval of 120s.

This paper introduced a pilot implementation of Support Vectors Machine (SVM), a new machine learning algorithm, for traffic condition prediction utilizing the data collected in traffic management center. A SVM^python based Level of Service Prediction System (LOS-PS) was developed in this study. ITS data collected from Transguide program in San Antonio, Texas were utilized to implement the proposed LOS-PS system in the case study of this paper.

We encounter high dimensional data when using time series vector to describe the traffic flow of a certain link during some time period, or using flow data from different links to describe the traffic status of a region at a certain time point. This paper applies a dimensionality reduction method, named Locally Linear Embedding (LLE) to extract temporal and spatial features out of these high dimensional traffic flow data. LLE can visualize our data in a low dimension space, thus giving a vivid perspective on the emerging features. According to these features, we can put links into different clusters and better interpret the evolution of traffic patterns. Furthermore, comparison between linear dimensionality reduction method, PCA and LLE is carried out. The result shows that LLE has better performance.

From the perspective of time and space, this paper proposed traffic congestion index system based on data collected from RTMS of Beijing expressway. Traffic congestion condition in various time granularities and various space granularities can be evaluated by traffic congestion index system. Performance characteristics and trend of traffic congestion of Beijing expressway can be obtained and evacuation capacity of road is also evaluated by these indexes. Based on study of traffic evaluation index, this paper further proposed the prediction approach on traffic congestion index.

This paper discusses some complex Hardware-In-the-Loop configurations used for evaluating three distinct control strategies aimed at minimizing dilemma zone problems at high-speed, rural intersections. Five intersections were studied; three configurations were tested. The authors show that effective Hardware-In-the-Loop Simulations can be created for complex signal control configurations. They demonstrate that it is important to become familiar with the electrical details of the components and then create software and hardware splices that tie the devices together in such a way that each one functions in the manner intended. The authors show that for speed traps, the time step in simulation models dictates longer-than-field-based separations, about 29 m (95') instead of 6.6 m (20') (as in the field). This clearly suggests that time step duration has a significant impact on the results obtained for HILS, and hence suggests it worthwhile to push that frontier further, striving for even smaller time steps so that HILS can be effective.

This paper proposes a new modeling approach for estimating road travel times in the territory-wide network. Owing to the rapid development of Intelligent Transportation Systems, travel times can be observed on links and/or paths in the road network by different sensor systems. The observed data from multiple sensor systems can provide more comprehensive and complete information on network-wide travel times than those from one sensor system. Thus, the use of the multiple sensor systems may have the potential for more accurate estimation of travel times in the territory-wide road network. However, the traditional travel time estimation methods typically consider the observed data from only one sensor system. The reason is that the observed data from different sensor systems may be inconsistent, which may bring difficulties in using these inconsistent input data for travel time estimation. This paper proposes a new two-stage model to overcome such data inconsistency difficulty for travel time estimation in the territory-wide road network with partial observed data from multiple sensor systems. In the first stage, the link travel time covariance matrix estimation model is proposed to estimate the covariance matrix of the link travel times for the whole network with the use of the second-order statistical property of the observed data from multiple sensor systems. Then, mean travel times on the links without sensors are updated according to the resultant estimated covariance matrix. In the second stage, a generalized least squares model is adopted to explicitly consider the data inconsistency issue for estimating the network-wide mean link and path travel times using the first-order statistical property of the observed data from multiple sensor systems. A heuristic solution algorithm is proposed for solving the two-stage model. A local road network in Hong Kong is used to demonstrate the applications of the proposed modeling approach.

Traffic data is very important for Intelligent Transportation Systems. The traffic data is collected by different types of detectors. However, the data collected by these detectors cannot meet the precision and completeness requirement of ITS. To improve traffic data's completeness and comprehensiveness, this paper addresses a problem when road sections have no GPS sampling signals based on floating vehicle systems. A robust Kalman Filter fusion algorithm is proposed to fuse the information of associated road sections, of which traffic information is known, and to obtain the traffic information of the road sections without GPS sampling signals. The method is verified with the real GPS traffic data of Hangzhou city, China, and compared with the standard Kalman Filter algorithm. Finally, experimental results show that the proposed fusion method is effective and can provide more precise and comprehensive traffic information for traffic managers.

In most of the existing highway capacity manuals, the traffic quality of critical areas (weaving, merge and diverge segments) at intersections on freeways is investigated separately. A total assessment of an intersection is therefore not available. This paper presents a new model considering the desired traffic quality of the total intersection. A combined degree of saturation which is defined as a function the degrees of saturation of the critical areas is used for defining the traffic quality. This model is already incorporated in the upcoming German Highway Capacity Manual (HBS2011).

Automated truck lanes (ATL) can solve some future problems caused by greater freight transportation demands. This paper proposes an integrated microscopic-mesoscopic simulation framework for precisely estimating the environmental impact of ATL systems on large traffic networks. Microscopic car-following and lane-changing models are extended to reflect the detailed interactions between cars and trucks. Fundamental experiments on one segment of an ATL show that the ATL system is the best of the various available strategies. Finally, Analysis on large traffic networks indicates that the ATL system has the lowest environmental impact among the cases, with the lowest CO₂ emissions not only on the expressway itself but also on associated expressway networks and the total road networks.

Research on design speed of TER (truck escape ramp) was carried out in order to make it more cost-effective and safer. The data of 9 TERs of Yuanmo Expressway has been collected. Back analysis method was brought forward and adopted to analyze the speed of out-of-control vehicles entering arrester bed. According to distribution of vehicle speed data, the speed of vehicles losing braking capabilities that met a probability were obtained, which could be used to determine TER design speed. The result also showed that 99 percent of vehicles' speed was lower than 102.2 km/h, which was much lower than the speed of 130 km/h introduced internationally. The TERs designed by using this result has opened to traffic for one year. No traffic accidents occurred yet caused by improper settings of TER.

The repealing of the national minimum speed limits in the U.S. gave states the freedom to set their own speed limits on non-interstate highways. Texas adopted different speed limits for cars and trucks dependent on the time of day. The purpose of this study is to evaluate, if the drivers are following the different speed limits during day and night time on various types of highways. Speed data were collected on the following highways: Interstate Highway-I37, Multilane Divided Highway-US 77, Farm Road-FR 665 and FR 70. Various statistical methods were applied to analyze the collected speed data. It was found that the most of car drivers on highways and truck drivers on farm roads do not follow the posted speed limits. The 85th percentile of traveling speed on the studied highways and farm road is 70mph ±2mph with irrespective of type of vehicle and time of the day.

Faced with severe problems of traffic congestion and safety, the United States of America has carried out research and application of access management techniques, aiming to improve urban road transportation, which has produced very good social and economic benefits and can be adopted by other countries. In China, urban arterial roads often have too many access points, which is one of the main causes of traffic congestions and traffic accidents. The paper has primarily studied unsignalized access points on arterial roads with two lanes in each direction, using a microscopic traffic simulation. By analyzing average delay time of the minor road approach in many situations, standards concerning traffic volumes of the intersection approaches have been given. When traffic volumes are beyond the standards, higher levels of access control should be considered. Results of the paper are very helpful for application of access management techniques.

Some proposals on classifying freeway exit ramps in China are put forward. Google Earth was used to identify the contributing factors on exit ramp classification by surveying more than 500 samples in China, USA, Japan, and Europe. The factors determined are configuration of deceleration lanes, number of deceleration lanes, lane changes in the mainline upstream and downstream segments, and number of ramp lanes. With the classification, four freeway exit ramp types are proposed. Furthermore, traffic operational performances of different types of freeway exit ramps were evaluated by studying traffic operational speeds (in the upstream segment, downstream segment, and exit ramp segment) and capacities by TSIS package and field observations. Thus, reasonable exit ramp types are proposed in order to satisfy the different operational requirements.

In this paper, the capacity of the weaving section, in which an on-ramp and an off-ramp are joined together by an auxiliary lane, influenced by the inflow rates of drive-in and drive-out vehicles is investigated. The drive-in vehicle should merge into the main road while the drive-out vehicle should diverge from the main road. When the number of drive-out vehicle is larger than the number of drive-in vehicle, the total flux can be reduced to lower values. The drive-out vehicle is difficult to enter into the off-ramp then it queues up at the weaving section and blocks the following traffic. Thus the flux on the off-ramp is much lower than the inflow rate of drive-out vehicle and the traffic on the main road is greatly disturbed. As to the length of the weaving section, it should be better larger than 150 m.

To ensure traffic flow on urban expressway running safely and efficiently and perfect the designing standard of interchange spacing, it is necessary to study the length of acceleration and deceleration lane on urban expressway. Based on the vehicles' running characteristics, the acceleration lane was divided into three sections, namely acceleration section, waiting merging section and width transition section. Applying dynamics theory, the models calculating the length of acceleration section and width transition section were got. By combining probability theory and differential method and taking main lane traffic volume into consideration, the model calculating the length of waiting merging section was established as well. Then, the twice deceleration theory put forward by AASHTO(American Association of State Highway and Transportation Officials) was adopted to analyze the vehicles' running process on deceleration lane. The deceleration lane was divided into three sections, too, i.e. width transition section, the first and second deceleration section. Applying the dynamics theory again, the model calculating the length of width transition section was got. Applying dynamics theory and taking drivers' driving comfort into consideration, the models calculating the length of the first and second deceleration section were established as well. And then, taking mainline lane vehicles' time headway distribution and mainline lane and ramp vehicles' velocity combination into consideration, the length values of acceleration and deceleration lane on urban expressway were calculated. The calculation results indicate that the length of acceleration and deceleration lane increases with the increase of mainline lane vehicles' velocity and decreases with the increase of ramp vehicles' velocity.

When considering the engineered traffic safety measures against speeding accidents, it is important to know the speed perception structure of each driver. However, how modeling of the speed perception structure can be achieved in theory has not necessarily been carried out in traffic engineering research up to now. If a speed perception structure model can be theoretically derived, a speed choice behavior model incorporating such a perception structure can be expected to be one of the powerful engineered analysis tools for analyzing the effect of traffic safety measures taken against speeding accidents caused by a driver's misperception of speed. The purpose of this paper is to suggest a theoretical model for driver perception of vehicle speed, and to verify the model by conducting in-house experiments with a driving-simulator. The model is built on the basis of knowledge of visual perception psychology research. In the model, a mathematical relationship between the respective time-rate-of-changes of the actual and perceived speeds can be derived, obeying a power law with respect to "sensitivity", which is defined as a new indicator in this paper. Then, the model shows that the sensitivity produces "over-perception of speed" in theory. Through statistical tests from the results of the in-house experiments, this paper shows that the model is statistically valid.

Railroad network is similar in some conceptions to electric current, such as a fulcrum station to a node, the car routing to the current loop and the car flow to electric current, etc. So it could put some concepts of circuit into car routing, for example, it can make formula about the traffic flow volume at the fulcrum station, which any of fulcrum stations replaces a node in circuit and the traffic flow volume passed replaces the electric current. Based Kirchhoff's electric current law, the paper addresses the car flow routing and distribution model. This model aims to minimize the expected total cost. The model can get car routing and distribution at the same time, avoiding the double-calculation (solved the car flow routing and then worked out the distribution by some traditional ways). Based on the Lingo which is implemented in C#, the paper solved the numerical experiments under the railroad network environment. The results show that this model can satisfy the actual needs and has strong adaptability.

High-speed, rural intersections with both passenger car and truck flows present dilemma zone challenges. Three signal-timing strategies were tested in the field at three intersections of varying geometries with the goal of minimizing the occurrence of dilemma zones without sacrificing efficient operation. The strategies focused on hardware changes impacting vehicle sensing as well as mainline green phase extension and termination. The base strategy was volume-density control. The second one (NQ4) added advance detection of high-speed trucks triggering a fixed green extension. The final strategy replaced the second system with a sophisticated advance detection and control system (D-CS) logic based on the work of Bonneson et al. (2002). Results indicate simple volume-density control is surpassed in safety by both other strategies; moreover, the detection-control system dramatically reduced the number of vehicles trapped in dilemma zones at the onset of amber. The second strategy works fairly well in the field. The drawbacks to the NQ4 system are most noticeable at high-volume intersections — it does not actually find times when no vehicles are in dilemma zones, vehicle speeds are not directly used for computing main street hold times (which is accomplished in the D-CS control strategy resulting in improved efficiency), and it is a bit cumbersome and expensive to install. Based on our findings, the addition of the DC-S algorithm into a controller is a worthwhile investment for mixed-traffic, high-speed, rural intersections with dilemma zone issues.

The county economy in China is the fundamental regional economic unit, and the passenger transport volume is one of the basic indicators to reflect a county economic development. In this paper, by considering the characteristics of the operation of passenger highway transport, the operating passenger cars would be divided into three classes: 1) cars that take operation in the passenger terminal, 2) cars that do not take operation in the passenger terminal but with fixed-lines, and 3) cars that are rentals. Their investigation methods are - statistical reports collection or the concentration survey in passenger terminal, car-survey method and sample survey method in business place. According to general characteristics of the above three types of passenger transport volume and the actual survey conditions of grassroots management departments, the simplified, easy-to-use statistical model was proposed. It is a two-stage calculating model, which combines multi-class traffic projections and road network transport volume (fluctuations) projections. Finally, the feasibility and effectiveness of the method have been verified by the investigation of a county in Heilongjiang Province.

Transport and traffic data collection methods have developed along two main directions. One is the off-line method using pen-and-paper surveys or face-to-face interviews, and the other is the on-line method using internet surveys or XML messages from companies' administrations. The transport and traffic statistics based on these data are rather static representing an average, macro-view of transportation. In order to further enhance transport and traffic statistics, linking traffic to social economic fields, real-time collected data based on GPS/GSM should be available. Marked advantages of GPS and GSM data collection are that transport and traffic data are captured automatically at highly frequent rates, which provide dynamic information and offers opportunities to reduce administrative burdens. And also with the help of GPS information, the individual vehicles can be identified by connecting with other data source. However, though GPS/GSM data collection sounds a promising technology, its adoption is seriously hampered by the fact that few vehicles are equipped with GPS transponders and that not all drivers use a GSM. GPS/GSM-collected data thus constitute only a limited part of the whole transport and traffic data for a delineated area and specific time slots. In this paper, we aim to validate the usage of GPS information for traffic statistics. Traffic density is theoretically applied to integrate traffic engineering, social economy and statistics methods. Then with the limited number of GPS/GSM vehicles, we take their advantages of doing the timing and identification issues for carrying out density estimation. Further, statistic method of Horvitz-Thompson is used to up-scale the dynamic density to the whole network and time period for official statistics.

Accessibility is a fundamental indicator of location advantages. This paper presents one algorithm that measures time accessibility of public transit network using the bus line flow and transfer flow information. It first obtains flow and transfer information from the IC Card Toll System and estimates the transition probability matrix. Then the service area of bus stops is bisected by a Voronoi diagram. The time cost walking to and from bus stops is calculated. Finally, the average travel time cost of each location is calculated. One real-world public transit network in Kunming is calculated using this methodology. The area covered by the public transit network is first partitioned by 10m* 10m grids. And then the travel time cost of every grid is calculated, which forms time contours.

Public transit route choice is the key technology of the public transit passenger information system. In this paper, a public transit route inquiry theory, which is based on the difference in travel behavior of public transit passengers, is presented. The critical issue in the theory is to analyze the optimization inquiry objectives, which consist of transfer times, travel time and travel costs, and to design the different algorithms. Combined with the characteristics of geographic information systems (GIS), a public transit route inquiry system is developed. It is not only able to provide accurate, reliable and comprehensive information service for passengers, but also to provide intelligent decision support for the bus company in bus dispatching management. Application in the public transit network of Lanzhou city showed that the proposed algorithm was feasible and effective. Furthermore, the system was intuitive and had a friendly interface that was easy and simple for users to operate.

Aiming at synchronization of train blocking and scheduling problems both in space and time, this research first constructs a conceptual framework for synchronizing train blocking plan and train timetable, based on a feedback mechanism between them via "quasi train path graph". On the basis of the conceptual framework, a bi-level mathematical programming model and improved genetic algorithm are proposed. Finally, comprehensive numerical experiments including both fixed fee and variable fee are conducted to demonstrate applicability of the above method. Results show that solutions of this model could identify train operating time window and train series for each goods OD. In addition, the solutions have considered connection time for train blocks in marshalling stations so as to make the train blocks controllable.

Energy efficiency of trains is an important and beneficial task. According to the research conducted on energy-efficient control both by domestic and international professionals, it is studied that the energy-efficient algorithms of the train of Urban Rail Transit with fixed running time. The algorithms adjust the maximal speed of whole lines and minimal speed of sections, which are used as the limited speeds, according to a given operational time. At the same time, using a forward calculating algorithm makes the best use of coasting to reduce times and time of traction and braking, which helps to decrease energy consumption. A computer simulation system has been developed, and some cases have been designed and analyzed for train movement under different times and different loco-tractions. It provides a method for optimizing real control model of the train of Urban Rail Transit.

With the novel technologies used in railway track status inspection, more and more track geometry data can be obtained, and they play a great role in ensuring track in good conditions. But, for the same section of the same track, there are also mileage errors between the track geometry data from the different inspection dates, so, in order to eliminate these inverse effects on the analysis results and avoid non-effective track maintenance works caused by the above mistaken data, a new optimization model to correct the mileage error of the track geometry data is put forward in this paper, and a automatic mileage error correction software based on the above model is developed at the same time. Based on a large amount of track geometry data from Shanghai-Nanjing railway line, the model verification and analysis are completed by the above software efficiently, the model is proved to be correct and effective.

Since more and more inter-city railways are being constructed in China, the operational management of inter-city railways is becoming much more important than ever. Based on the infrastructure and operational requirements of inter-city railways, the relationship between train departure mode and line capacity is discussed. Train departure mode is the basis of cyclic timetable development, which must suitable for the operation of inter-city railways. Factors affecting period of train platoon are analyzed and the calculation method of minimum period is constructed. The composition of different types of train platoons is discussed under the contradiction between the usage of line capacity and the level of operational service, which provides a method for the timetable development. Next, the design scheme of a soon-to-build inter-city railway is analyzed by developing cyclic timetables by using the proposed method and the computational results show that in this case study, the designed line capacity is inadequate to operational requirements in the long run. Finally, suggestions are given and improvements of the new design scheme are verified by using this method as well.

As the Chinese transport system began to develop rapidly, researchers became highly concerned about the reform of wagon flow organization. The traditional modeling and optimization method of wagon flow organization based on concentrated decision-making doesn't sufficiently support the exploration to the decision process and method of wagon flow organization with the innovation for railway transport mode currently. In this paper, we study the decision-making method of wagon flow organization, which is based on distributed autonomous decision-making in a manner of competing resources according to different wagon flows property in the process of organization. Each distribution agent competes and cooperates with the other according to competing ability in order to make more profit, the system arrived the state of global optimization in the process of conflict and coordination. Furthermore, a multi-agent model on wagon flow organization is presented. The modeling method is tested on experimental computation.

The track allocation problem (TAP) at a multi-track, multi-platform mainline railway station is defined by the station track layout and service timetable, which implies combinations of spatial and temporal conflicts. Feasible solutions are available from either traditional planning or advanced intelligent searching methods and their evaluations with respect to operational requirements are essential for the operators. To facilitate thorough analysis, a timed Colored Petri Nets (CPN) model is presented here to encapsulate the inter-relationships of the spatial and temporal constraints in the TAP. The relationships among the static station track layout, TAP solution and the available buffer times are described by the model and it allows systematic representation of train movement at stations and hence analysis on TAP solutions upon service disturbances.

Train scheduling of passenger dedicated lines pay much attention to provide convenience and express service. It is different from train scheduling of exiting railway which is base on determined passenger train lines and mainly schedule freight train lines. This paper builds an integer linear programming model with weighted sum of passengers' travel time and waiting time when transfer between trains as objective, and proposes a rolling optimization approach which solve the model hour-by-hour. The numerical example shows that this rolling approach can solve the problem more efficiently than directly solve the model.

With Chinese economy speedup since late 1990s, it was required that large numbers of construction of civil engineering projects, and passenger transport special railway was the results of economic development. CFG (cement fly ash gravel) is one of groundwork reinforced methods widely used in civil engineering. And CFG was also applied in the construction of Wu-Guang passenger transport special railway. However, according to field investigation, it was found that groundwater in Haudu to Shaoguan in Gunagdong province containing lots of sulphate, which can result in corrosion damage of underground CFG pile. Therefore, in order to improve service life of CFG pile, it is necessary to increase the capability of CFG corrosion resistance. In this paper, influence of compositive materials such as water to binder rate (w/b), fly ash to cement rate (F/C) and quantity of cement on mass change of CFG in sulfate sodium solution, permeability coefficient and compressive strength of CFG were studied. Results show that with the increase of w/c, mass of CFG increase quickly first and then keep steadily. The increase of F/C and cementious addition in CFG can decreases the mass increase rate of CFG effectively. The increase of w/c and cementious addition increase permeability coefficient of CFG. And there exits an optimal F/C (1.0–1.2) in CFG , making permeability coefficient of CFG decrease to the least at 28 day ages. When CFG is immerged in water and sulfate solution respectively, the compressive strength of CFG immerged in sulfate solution is higher than that immerged in water at 28 day ages. With w/c, F/C and cementious addition increasing, the compressive strength of CFG decreases. There are acicular ettringite crystals in CFG after immerged in sulfate solution.

Both Chinese and foreign researchers have developed linear models to predict track irregularities. These models adopt the Track Quality Index (TQI) as an index to evaluate overall track irregularity. In these models, an averaging method is employed to calculate the slope k of track irregularity over a particular track section and k is then used to predict future TQIs. However, complicated factors affect track irregularity. Roadbed state, passing tonnage, train running speed and track structure are all important factors that determine track irregularity changes. Under the joint action of various factors, changes in track irregularity are characterized by nonlinearity, which can be described the so-called Bathtub Curve. Linear prediction models provide a simple but convenient tool to predict the evolution of track irregularities. In a certain sense, these models help to deepen research and can shed new light on the pattern of track irregularity changes. However, these models inevitably have two obvious disadvantages. The first is that no systematic consideration is given to the inherent characteristics of track irregularity changes, while the second is that it is apparently impractical to use a single slope k to predict track irregularities for all track sections of a whole railway line. The result is that when linear models are used to predict track irregularity changes, big predictive errors are caused. In the light of the cyclic, exponential and multistage changes in track irregularity, the current authors have developed a multistage linear prediction model for track irregularity. Given the cyclic nature of track irregularity changes, we take a 200 m track section as the unit section for our research. Because track irregularities change at different rates within one track irregularity development cycle, we divide such changes into several shorter stages. Based on our understanding of the three major characteristics of track irregularity changes, we put forward an improved linear prediction model, namely the multistage linear prediction model (MLPM). The model adjusts the calculation method of k to make the predicted results fit better with the actually measured values. The authors finally use track car inspection data from the Beijing-Shanghai Railway Line (Jing-Hu Line) to validate the model and compare the predicted results with the measured data.

The authors conducted research on the changing regularity of local alignment irregularities with the gross passing tonnage and built the deterioration model of local alignment irregularities. And after analyzing the data of the Chengdu-Kunming Railway (Cheng-Kun Railway) administrated by the Kunming Railway Bureau, this paper provided forecasts of the development of alignment irregularities of the railway. In the paper, shorter track segment is taken as the study object. During a maintenance period, the trend of the amplitude of local alignment irregularities is increasing the curve line with gross passing tonnage rising. Railway Engineering manages alignment irregularities through four management standards which base on peak values of alignment irregularities. On the basis of the management standard, this paper has researched the changing regularity of alignment irregularities with gross passing tonnage in unit section and built the prediction model of the amplitude of alignment irregularities in unit section. Making use of the actual data of rail lines in our country, the paper has forecasted the development of alignment irregularities of the rail line. Examining combined transportation and dispatch data of the Cheng-Kun Railway of the Kunming Railways Bureau from March 2008 to December 2008, this paper calculated the gross passing tonnage in days and collected the relevant data measured by a track geometry car. Using statistics and probability theory and function, this paper analyzed the relation between the amplitude of alignment irregularity of lots (3 m in length) and gross passing tonnage and built the local alignment irregularities deterioration model to forecast the development of alignment irregularities. After comparing predicting data with actual data and analyzing the error, the accuracy of the model was verified.

Railway track is one of the main railway facilities and the basis for trains to operate on. In order to keep passenger and freight trains moving safely, stably and uninterruptedly, the railroads must ensure track roughness low. The launch of high-speed and high-haul trains requires lower roughness of track, and consequently expects the railroads to accurately maintain or repair railway track. In this paper, base on the characteristics of changes in track irregularity, we have developed a mathematical model called SRPM which uses track waveform data generated by track geometry car (TGC) to predict the track irregularity over a short track section with the length of 100m for each day in a future short-range period of time. For verify the effectiveness of SRPM, we applied the model to 25 sets of TGC-generated track waveform data from Beijing-Shanghai railway (Jing-Hu railway) administrated by Jinan Railway Bureau (JRB) to make short-range predictions for track irregularity over each unit section of the line segment. Finally, these SRPM predictions were analyzed in both spatial and temporal dimensions. From the analysis results, we come to the conclusion that SRPM developed in this paper can fairly accurately make short-range predictions for track irregularity over each unit track section of the JRB-administrated Jing-Hu railway.

The organization of long-distance passenger flow plays a vital role in the process of line planning. It can improve the efficiency, capacity utilization, and service quality of railway transportation. The organization of long-distance passenger flow is a hot but hard topic, as it involves so many factors and the relationship among them is very complicated. This paper focuses on the organization mode choice of long-distance passengers under different conditions. First, the basic organization schemes of long-distance passengers are discussed. Then, the influence factors of operating long-distance passenger trains are analyzed. In order to evaluate different passenger organization schemes, a cost function is established. Next, a numerical example is presented and examined. The result of the numerical example shows that the proposed method can offer support for decision-making of railway operators. Finally, as passenger transferring is unavoidable sometimes, methods for improving passenger transferring efficiency are discussed.

Long-distance passenger trains are very popular in other high-speed railway countries and on traditional railway lines in China. However, the organization of long-distance passenger trains can be complicated on passenger dedicated lines in China, for it is affected by many factors. In this paper, we focus on the analysis of the factors to develop the conditions for operating long-distance passenger trains on railway passenger dedicated lines. Since different factors have different degrees in affecting the operation of long-distance passenger trains, we discuss the combination effect of different factors. Based on the analysis, we propose the conditions for operating long-distance passenger trains on passenger dedicated lines, including train units travelling distance, and train departure and arrival time windows. Finally, we discuss the relationship between train stop schemes and train departure and arrival time windows of the Beijing-Shanghai high-speed railway line.

Safety Management System (SMS) is currently being advocated by civil aviation community, and has been introduced in China in the last few years. This paper covers perception of SMS, discusses some fundamental issues concerned. It tries to present a clear view of SMS, furthermore, hopefully leads to a better understanding and implementation.

A rational slot allocation for flights is very important to ease the congestion in airspaces or landing airports. Based on the analysis of slot allocation algorithms of foreign air traffic flow management systems and with the combination of the domestic air traffic flow management situation, a flight slot allocation algorithm suitable for China is proposed. Test of the algorithm indicated that the proposed flight slot allocation algorithm is reasonable, effective and practical, which satisfied the principles of overall optimum, fair and reasonable for ground delay flights.

The continuing growth of aviation places increased demands on airspace capacity and emphasizes the need for the optimum utilization of the available airspace, which demands the navigation system being especially reliable after an aircraft approach has commenced. Navigation technology development in GPS from USA, Compass in China, and Galileo in Europe provides the foundation for aviation's global evolution. Area navigation (RNAV) is a method of navigation that permits aircraft operation on any desired flight path and Required Navigation Performance (RNP) is a statement of the navigation performance accuracy necessary for operation within a defined airspace. All elements of communication, navigation, surveillance (CNS), and air traffic management (ATM) are combined into a CNS/ATM-based system in which RNP/RNAV provides the path for this transition. On the other hand, GNSS evolutionary architecture (GEA) and updated requirements need to be studied. In this paper, analysis and detailed differences between RNAV/RNP toward navigation specifications are first carried out, then key technologies in GEA study panel (GEAS) including three candidates such as GIC, RRAIM, and ARAIM are studied; at last corresponding algorithm and basic architecture are proposed to test the capability of ARAIM implementation with frequency diversity. The idea discussed in this paper is suitable for the development of satellite navigation utilization in civil aviation and helps determine future air traffic management policy.

In present scenario, non-availability of the conventional materials for construction of subbase of flexible pavement in many places in India has become one of the greatest problems for constructors due to variety of reasons. This problem may be overcome by decreasing the thickness of the sub-base layer by improving their strength, which ultimately reduces the cost of construction and also elongates the life span of pavement. In view of this, an experimental program was undertaken to study the possible uses of jute-geotextile in the construction of Granular Sub base layer of flexible pavement, with moorum and sand to evaluate their usefulness as a better sub base material and the result of these tests are reported in this paper.

The paper discusses the successful adoption of four major types of pavement materials in Hong Kong, namely porous asphalt, recycled asphalt pavement, asphalt rubber and stone mastic asphalt, based on the research works carried out in recent years by the Hong Kong Road Research Laboratory. Regarding the porous asphalt (PA), the study results indicated that the design with polymer modified binders exhibit smaller temperature susceptibility and higher resistances against ageing, rutting and fatigue than the one with conventional penetration 60/70 binder. For the study of new pavement incorporated with 15% of recycled asphalt pavement (RAP), it was found that the RAP materials performed as good as the control mixture of virgin material in terms of stiffness, water sensitivity, rutting and fatigue resistances. The site and laboratory testing results of asphalt rubber (AR) showed that the performance of the asphalt rubber wearing course was better than that of the conventional wearing course in providing good rideability, good fictional property, high water damage resistance and quiet surface. The properly designed stone mastic asphalt (SMA) mixture with modifier and admixture were able to enhance the rutting and fatigue resistances of a conventional SMA material. It is anticipated that the future direction of pavement engineering research in Hong Kong will be a more prominent utilization of accelerated pavement testing technique, and the first step taken would be the development of an accelerated pavement testing (APT) facility which will also be highlighted towards the end of the paper.

Asphalt mixture is a complicated thermal rheological material, and its deformation is related to some factors, such as the stress state, stress history, temperature, and loading rate. So it has a very complicated nonlinear viscoelastic property. To find a nonlinear viscoelastic constitutive model of aged asphalt mixture, stress relaxation tests were carried out on asphalt mixtures (AC-13C), having five different aged degrees, under different temperatures and strain levels. Then, a fractional exponential model was founded to characterize the stress relaxation performance of aged asphalt mixture, and the regression relationships of the values of the model parameters, varying with the aging degree, strain and temperature, were established applying the non-linear regression method according to the test results. Finally, a nonlinear viscoelastic model of aged asphalt mixture was established.

Rutting in asphalt pavement can be influenced by many factors of high-temperature stability of mixture. Taking three continuous-graded and two gap-graded asphalt mixtures as investigation objects, Dynamic Stability (DS) and Rutting Depth (RD) were measured in cases of different temperatures, wheel rolling times and contents of a new anti-rutting agent (ARK-1) by Wheel Tracking Test. The results of testing showed that resistance to rutting of the fine aggregate mixture would be superior to that of the coarse aggregate mixture. No obvious differences between the continuous-graded and gap-graded mixtures could be observed in resistance to rutting as temperature was equal or lower than 60°C. High-temperature stability of the gap-graded or coarse aggregate mixture was better than that of the continuous-graded or fine aggregate mixture as temperature was beyond 60°C. ARK-1 could dramatically improve resistance to rutting of the asphalt mixture. A project example on Baotian freeway between stations 35+460 and 36+460 proves that the costs of pavement made with ARK-1 will be more economical than pavements with SBS-modified binder.

In precast concrete elements manufacturing, steam-cured concrete incorporating 30% fly ash encountered the problem of a too low demoulding compressive strength. To resolve it, this paper developed a new steam-cured concrete (AFSC) incorporating fly ash and a chemical activator. Experiments were conducted to investigate the mechanical properties of AFSC. The corresponding mechanism was also discussed by testing the microstructure of concrete. Results indicate that the demoulding compressive strength of AFSC can meet production requirements, and compressive and flexure strength of AFSC at later ages increase well. Compared with that of ordinary steam-cured concrete, AFSC has a higher tensile strength, and the capability of AFSC to resist cracks is enhanced remarkably. At an early age, addition of the chemical activator can distinctly accelerate the extent of hydration of the fly ash cement systems, and thus the microstructure of concrete becomes denser.

In order to improve the anti-slide performance for an asphalt pavement surface, the anti-sliding property of pavement was analyzed in this paper; the fiber additives in asphalt mixture were compared. Furthermore, certain groups of comparative experiments were conducted by adding the different length and different quantity of the sisal fiber toward the bituminous mixture and showing that the sisal fiber is the best asphalt mixture additive to improve the anti-slide performance for pavement surface. The best length and the best quantity of the sisal fiber in the bituminous mixture were determined.

An electrically conductive porous asphalt concrete used for induction heating and subsequently healing of cracks is prepared by adding conductive materials (steel fibers and steel wool) in this research. In this paper, the optimization of steel fiber used for induction heating is reported based on the electrical resistivity, induction heating speed and particle loss resistance of porous asphalt concrete. It is found that porous asphalt concrete containing steel fiber with smaller diameter or longer steel fiber is more electrically conductive and induction heatable than that containing the same content of steel fiber with bigger diameter or short steel fiber. It is also found that steel wool type 00 with length of 9.5 mm is more effective than short steel fiber type 1 and steel wool type 000 to improve the particle resistance of porous asphalt concrete. Finally, 8% (by volume of bitumen) of steel wool type 00 is considered as the best option used for induction heating in porous asphalt concrete.

With the increasing constructional activities in road sector, situation has arisen where conventional good quality soils for subgrade are in short supply in many locations due to variety of reasons. Particularly in densely populated areas this problem is very accute. On the other hand, due to rapid industrialization throughout the world, the production of huge quantity of waste materials creates not only the environmental problem but also the depositional hazards. Safe disposal of the same is very vital issue and such situation can be addressed by the bulk utilization of these materials mainly in the field of civil engineering applications. A systematic detailed investigation was undertaken by the authors for using rice husk ash (RHA) and pond ash with soils to enhance the quality of the soil as subgrade material. CBR value in soaked and unsoaked condition increases in a small amount for addition of RHA, but with addition of lime in RHA mixed soils, better increment has been observed in the CBR values both in the soaked and unsoaked conditions. Further mixing pond ash with the soil showed increment in CBR both in unsoaked and soaked condition and mixing of pond ash upto 150% has shown that the gain in CBR value is more than double for soaked and unsoaked conditions.

Skid resistance is one of the most important properties of asphalt pavements. Contaminants in asphalt pavements affect skid resistance at a certain extent. The detailed effects of contaminants on skid resistance of asphalt pavements were investigated. The core samples of AC-13, SMA-13, SHRP -12.5 and OGFC-13 compressed by the Superpave Gyratory Compactor (SGC) in the laboratory were used as pavement samples, which were usually applied in China. The lube oil, sand, earth, grit and water were chosen as contaminants. By testing skid numbers by British Pendulum Tester of the clean samples and the samples with contaminants in three contamination situations (little-covered, half-covered and all-covered), the effects of contaminants on skid resistance of dry and wet asphalt pavements were analyzed. It was proved that contaminants affected skid resistance of asphalt pavements distinctly. The knowledge gained in this study would provide guidance for the maintenance of asphalt pavements.

To explore a new type of basalt mineral fibers on the impact of asphalt mixture, fiber improving asphalt behavior was researched first. Through the test of asphalt mixture of three indicators with fiber content 0%, 0.2%, 0.3%, 0.4%, 0.5%, and 0.6%, characteristics of composite materials (fiber asphalt)were analyzed based on Einsteins viscosity equation. The effect of different fiber content on the Marshall stability of asphalt mixture, the residual splitting strength and water stability of Marshalls was also researched. The research indicated that basalt fiber had a significant toughening effect on asphalt, and penetration and the softening point to evaluate fiber asphalt mixture's viscosity properties of composite materials was appropriate. MS and MS0 results showed that basalt mineral fibers in the AC-16C were not more than 0.4% volume. With the increase of fiber content, the splitting strength of the asphalt mixture increased. When content > 0.30%, increase was not obvious but modulus and stiffness continued to increase to resist deformation capacity. Composite micromechanics theory explained the basic principles of basalt mineral fibers to improve the behavior of asphalt mixture strength.

To study whether vibration compaction on concrete bridge decks can cause damage to a bridge structure, based on the theory of vibration modal, the paper analyzed dynamic vibration modal and damping of common types of bridges. The analysis using dynamic vibration theory calculated the top four orders vibration modal and corresponding frequency of a common bridge and compared them with the frequency of a vibratory roller. The results showed that the fundamental frequency of the common bridge types first-order vibration modal was between 5&–7 Hz (Zhao et al. 2008), while the frequency of a vibratory roller is 30 Hz. Usually, the top 30 orders of frequency of the common bridge can't reach the frequency of the vibratory roller. As a result, the probability of roller vibration damaging the overall bridge is small. Vibrating rollers can be used on the deck pavement compaction.

The paper uses rubber asphalt concretes trabecular, carries on the bending creep experiment on the MTS810 material testing machine, and the viscoelastic analysis. The bending creep experiment and the viscoelastic analysis indicated that the rubber asphalt concretes' creep compliance is lower, namely under the unit load condition the rubber asphalt concretes' distortion is small. Along with stress level's increase, the creep strain speed growth is slower, and the rubber asphalt concrete has a good resistance to permanent distortion ability.

Shrinkage performance is always considered as the most important characteristic of cement-treated macadam base. By using different gradation types and different levels of cement stabilized macadam mixture, the paper conducts indoor performance tests to study the mixture's shrinkage performance. Based on the tests, estimation formulas on shrinkage coefficients of the cement stabilized macadam mixtures are then elaborated. Results of the test indicated that mixes possess the lowest dry-shrinkage when 3%∼4% cement dosage are used, while temperature-shrinkage increase with cement dosages are added. Otherwise, more close-grained mixes with that have a better dry-shrinkage performance, while the temperature-shrinkage performance of these kinds of materials is worse than the sketch-grained mixes. Further analysis and test results show that shrinkage stress in base rises as cement dosage increased; a smaller cement dosage of base materials, as long as strength meets the requirement to reduce shrinkage crack in base, is feasible. Large numbers of project experience indicate that dry-shrinkage mainly occurs within 20 days when base construction complete. Moreover, compared to the continually cold winter, cracks easily form, when the temperature changes suddenly even in warm weather. Results of an indoor test show the same speciality.

In this paper, the vertical load-carrying natural frequency of 3 x 64 m through stud welding railway steel truss bridge is calculated using the vehicle-bridge system model, and the rule with time and some influence factors to the continuous bridge vertical load-carrying natural frequencies are analyzed, when 20 high-speed passenger vehicles with the same parameters are travelling on the bridge. The results show that when the vehicles are distributing on the whole bridge, the bridge vertical load-carrying natural frequency is periodically varied, and the periodic time is T=L_v/v. Also, the bridge vertical load-carrying natural frequency is related to the unsprung mass and the stiffness of the unsprung of each wheel-set of the vehicle, the vehicle's length, and the mass of the vehicle. But it is independent of the speed of the train. When the length of the train is shorter than the length of the bridge, the periodic changing stage of the vertical load-carrying natural frequency would never occur, and then the vehicle-bridge system would not incur vertical resonance.

Cracking is one of the main disease types of asphalt pavement. Currently, adding polyester fibers is one of the measures most commonly used to reduce cracking. Firstly, performance-enhancing mechanism on anti-cracking ability of asphalt mixture adding with polyester fibers was studied. Then, a typical polyester fiber was selected, anti-cracking ability of asphalt binder and asphalt mixture for different fiber lengths and different fiber dosages were tested. BBR test was selected to evaluate anti-cracking ability of asphalt binder while four-point bending beam test was selected to evaluate anti-cracking ability of asphalt mixture. Study showed that anti-cracking ability of asphalt was excellent when the length of polyester fiber is 6 mm, and the optimum dosage is between 0.2 ∼ 0.5% of the mixture.

The settlement after construction controlling of subgrade is a crucial issue on designing of high speed railway. Based on the experimental study at home and abroad, the centrifuge model test is used to imitate piled embankment in different pile spacing to research and analyze the settlement controlling ability of piled embankment in collapsible loess ground in high speed railway. Then the relationship between pile, lime-soil cushion, soil between piles controlling the settlement are concluded by analyzing the test data. The research results show that untreated ground which can not meet the request on settlement after construction in ballasted track in high speed railway need be reinforced. The total settlement, settlement after construction and settlement ratio of piled embankment get larger with the extending of pile spacing. The settlement of soil is faster and more increasing than settlement of pile, and pile-soil load share ratio get lower and negative skin friction of pile get more increasing.

There are many methods to determine a rational completion state. However, it is difficult to determine the optimal cable tension using just one method, besides, different methods must be adopted for different types of bridges. As a result, it is feasible to combine minimum bending energy with the influence matrix method. The basic approach is: the initial cable tension can be determined through the minimum bending energy method, then the cable tension is adjusted through influence matrix, whose constraint conditions are stresses of key sections and support reaction from the top of pier, at last, the optimal cable tension of the finished state is determined. This method is not only simple but also very clear, and it achieves a good effect in determining the rational completion state of this type of bridges.

A new kind of light polymer cement mortar (LPCM), cement-based intermediate layer modified by acrylic acid, was presented for a bridge deck, based on the advantages and great achievements of light concrete and polymer modified cement concrete in civil engineering. Also, a number of tests were carried out to investigate the performance of the LPCM, such as flexural strength, compressive strength, fatigue life, characteristics of stress-strain curves, and chloride ion penetration test. The results turn out that the density of mortar was about 1800 kg/m³, which means it is a light cement mortar. Acrylic acid does help to decrease the water-cement ratio, improve paste working property, increase flexibility and crack resistance of the mortar, but there is a best dosage of the acrylic acid. Mechanism analysis shows that high-tensile strength of the polymer membrane is the main factor to significantly improve the mechanical properties of the LPCM. It means that light polymer mortar is an excellent flexible cement material. And it can be used at some special places where the thickness, weight, and flexibility are limited, just like bridge deck pavement.

The paper mainly studies Yin He bridges' damage detection.This bridge was completed in 2000.In the morning of December 13 2001, a truck are bumped against #8 suspension rod of the bridge.Because the main loading consists of a rib arch and suspension rod, the paper analyzes L/2 across, L/4 across of the rib arch, and bumped #8 suspension rod different damage degree's dynamic characteristics. It concludes that the changing regularization of the whole structure's dynamic characteristic made it possible forthe damage detection to the rib arch according to the dynamic characteristic changing and strain modal.

Vehicle time headway is one of the most fundamental microscopic characteristics of traffic flow. It affects roadway safety, capacity, and level of service. An estimated average time headway can provide an input to intelligent transportation systems for the online monitoring of roadway safety. Single inductive loop detectors are widely installed devices in road networks to regularly measure traffic volume and occupation. The purpose of this paper is to investigate the recursive estimation of average headway using the information from a single loop detector in the scenario of light traffic (e.g. during early morning or late evening period for most of the sections of motorways). A set of recursive estimation equations is developed with a nice and neat form using Bayesian analysis. The incurred computational cost for updating the estimate of average headway is kept to be a minimum. The developed method is illustrated using real traffic data.

Trading facilitation means all the steps that can be taken for obtaining a smooth flow of trade in general. This term is used to illustrate all kind of non-tax barriers. From the point of view of the World Commerce Organization, commerce facilitation is limited only to simplifying and harmonizing the international commercial procedures, covering all activities, practices and formalities involved in the collection, presentation, communication and processing of the necessary data for goods' circulation in international trade relations. The main objective of this paper is to show how trade facilitation is meant to reduce the transaction costs and complexity of international trade in the Black Sea Area and to improve the trading environment in this area, while maintaining efficient and effective levels of government control. This can be done easily by using the simplification of procedures and formalities, the standardization and improvement of infrastructures and facilities, the harmonization of rules and laws applied. Therefore, the main goal of trading facilitation around the Black Sea is going to be emphasized by describing the reduction of transition expenses and the international trade complexity for business meant to improve the changing background of the Black Sea, keeping it efficient and profitable at the same time.

The objective of this research was to seek valid surrogates for crashes, so that more reliable decisions and proactive measures could be made to improve traffic safety. Inspired by the FHWA's Road Safety Audit program, this paper focused on tire skid marks. A case study was conducted on tire skid marks collected from selected freeway and arterial segments in the Reno-Sparks area in northern Nevada, USA. Parameters were identified to provide a possible guideline for skid mark classifications. Furthermore, linear regression was applied to determine whether skid mark frequency was a suitable predictor of crashes. The regression analyses indicated that there was a relatively strong linear correlation between skid marks and crashes on freeway segments but a weaker correlation on arterials. The frequency of tire skid marks on freeway was found to be statistically significant (at a confidence level of 95%) in being a predictor for crashes.