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    25 December 2015, Volume 15 Issue 6 Previous Issue    Next Issue

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    Service Reliability of Urban Rail Systems
    HO Tin-kin, BAI Yun, CAI Hao, LIU Hai-dong
    2015, 15(6): 1-5. 
    Abstract ( )   PDF (1175KB) ( )  

    Urban rail systems are now the main public transportation means in the major China cities. Capital investment on urban rail infrastructure in the last decade has been enormous and public expectation on service quality is rising significantly in China. It is the critical system performance indicator of a railway system and thus critical to high- quality service provision and full utilization of the infrastructure capacity. This paper reviews the methodologies of formulating overall reliability in urban rail systems and discusses the advantages of developing the notion of system service reliability to translate the engineering- oriented system reliability to customer- oriented service quality indicators. Research works on service reliability to effectively capture service quality in urban rail systems are also suggested.

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    The Joint Decision Making Research of Pricing and Seat Inventory Control Based on Supermodel Game
    GAO Jin-min, LE Mei-long,QU Lin-chi
    2015, 15(6): 6-12. 
    Abstract ( )   PDF (1638KB) ( )  

    In routes that many airlines operating in the air transportation market, the discount ticket pricing and reservation restrictions will not only affect their own benefits, but also affect another airlines’revenue. Taking competitive factors into consideration, the joint decision making problems of discount ticket pricing and seat inventory control (reservation threshold) among airlines under the same route competition are studied. On the basis of rational hypothesis, supermodel game theory is introduced to make a deep analysis of related problems. The existence of pure strategy Nash equilibrium among airlines’competition is proved, some characteristics of the equilibrium results are analyzed, and a sufficient existence condition of unique Nash equilibrium is presented. Finally, the effects on equilibrium behavior after the degree of competition changed are analyzed, and relevant conclusions are verified by examples.

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    Dynamic Impact Factors Analysis of China’s Foreign Trade at Coastal Waterways Based on State Space Model
    ZHENG Li, WANG Xiao-hui1,CHEN Quan-run
    2015, 15(6): 13-19. 
    Abstract ( )   PDF (1996KB) ( )  

    China’s ocean transportation for international trade plays a major role in global transportation for international trade, and port is the important link in international logistics transport. The international and domestic macroeconomic factors and their time impact trajectories on China’s foreign trade cargo handled at coastal seaports are investigated based on the state space model. The main findings are as follows. Since the financial crisis, the positive impact of world economic growth on China’s foreign trade cargo handled at coastal seaports is increased; the positive impact of the actual use of foreign direct investment is significantly weakened; the negative impact of fluctuations in the RMB nominal effective exchange rate is weakened; the positive impact of domestic economic growth is gradually weakened; the positive impact of investment on coastal transportation is increased. We obtain an indirect evidence for the transformation of China’s economic development from the empirical results, i.e. China is transforming from an export- orientationeconomy to a home-demand-economy, and then proposes the relevant policy recommendations.

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    Combination Optimization of Hinterland Transportation Modes Considering the Transport Eco-indicators
    HOU Lin-jie, ZHEN Hong
    2015, 15(6): 20-25. 
    Abstract ( )   PDF (1238KB) ( )  

    It can be observed that port related hinterland connections have experienced unprecedented growth over the last two decades due to the flourishing port economy. At the same time, this development has serious negative effects on the natural environment. In addition to the traditional decision objectives “lower transportation costs and shorter transportation time”, this paper adds “higher transportation convenience degree”which stands for the service performance objective and“lower carbon emissions and land occupation of transport”which are the two most important objectives of transportation ecological benefits into the optimized scope to construct the combination optimization model of port related hinterland transportation modes. In this paper, analysis method of attribute coordinate is innovatively applied to solve the multi-objective optimization problem as a weighting method which could precisely quantify the distribution of the psychology preference of a decision group. In the section of case analysis, an example is taken to verify the effectiveness of the model and the algorithm.

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    Impact of Emission Charging to Carpooling in Urban Roads
    DING Dong,SHUAI Bin,ZHU Jin-cheng
    2015, 15(6): 26-32. 
    Abstract ( )   PDF (1399KB) ( )  

    In order to investigate the impacts of emission charging to carpooling in urban roads, a bi-level programming model is proposed. The lower level describes the travelers’selections of travel modes as well as route choices while the upper level aims to maximize social welfare. A heuristic algorithm for the computation of the optimizing value of link toll patterns, traffic demands, social welfare, travel costs and emission is designed and then applied to compute solutions to a numerical example. The results demonstrate that emission charging could increase social welfare and facilitate more people to carpool, and carpooling do not restrain traffic demands. Carpooling cost has limited impact on carpooling and the social welfare promotes with higher emission weight coefficient as well as system efficiency. It is not always beneficial for traffic system with higher fuel efficiency. Thus it is necessary to capture optimal toll on the basis of the topological structure of traffic network.

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    Spatial Deprivation Characteristics of Public Transportation in Rapid Urbanization Area
    JI Xiao-feng, OU Si-jia, CHEN Fang, ZHANG Hong-da
    2015, 15(6): 33-38. 
    Abstract ( )   PDF (1628KB) ( )  

    In order to evaluate the equity of public transportation system in rapid urbanization area, and improve the spatial deprivation of public transport system. On the basis of building evaluation index system of public transport spatial deprivation, SPSS is used to analyze factors of evaluation index system. Then spatial deprivation characteristics are gained by applying GIS and Kunming Chenggong New District is taken as an example. Finally, some allocation strategies are proposed based on the principle of the regional deprivation compensation. The results show that the mode of spatial deprivation of public transportation in Chenggong New District can be summarized as“multi-core + local radiation”; Spatial deprivation factors of public transportation include public transport service factor and bus transit network coverage factor; The establishing comprehensive index model of public transport spatial deprivation can obtain differentiation characteristics of public transport spatial deprivation in different traffic zone.

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    A Combined Traffic Network Flow Prediction Method
    NIE Pei-lin, GONG Jun-feng
    2015, 15(6): 39-45. 
    Abstract ( )   PDF (1350KB) ( )  

    A framework that combines data-driven predictors and mesoscopic traffic simulators is proposed for traffic network state prediction. In the framework, the mesoscopic simulation model with network prediction ability is calibrated on-line by the highly reliable road segment traffic flow prediction results from the data- driven predictors. Therefore, the calibrated mesoscopic simulation system is able to capture the evolution of traffic flow and improve the network traffic prediction accuracy. A case study, which combines the road segment travel time predictor and the mesoscopic traffic simulator, is conducted to verify the effectiveness of the framework. The empirical results show that the framework fully utilizes the advantages of the two prediction approaches and achieves better traffic network state prediction performances than the method that applies the mesoscopic traffic simulation only.

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    Identification of Transit Commuters Based on Naïve Bayesian Classifier
    SUN Shi-chao,YANG Dong-yuan
    2015, 15(6): 46-53. 
    Abstract ( )   PDF (2152KB) ( )  

    The Naïve Bayesian Classifier method is applied to identify transit commuters, based on the data of smartcard and questionnaire survey in Xiamen. Firstly, we establish the Bayesian probabilistic relations between the interviewer’s category variable (commuters/non- commuters) and the bus travel information which are contained in both questionnaire and smartcard data. Then the NBC model is established and trained based on the obtained conditional probability. By using the questionnaire sample that does not participate in the training, then the prediction accuracy of the calibrated model is tested, and the success rate of the prediction is 88% . Finally, the validated NBC model is applied to the identification of transit commuters in smartcard data, the result shows that the number of transit commuters in Xiamen may range from 260,000 to 320,000.

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    Development and Testing of A Smartphone Eco-driving App
    ZHAO Qi, ZHU Si-cong, YU Lei, SONG Guo-hua
    2015, 15(6): 54-59. 
    Abstract ( )   PDF (1695KB) ( )  

    Aggressive driving is responsible for a significant share of vehicle emissions. This paper attempts to develop and tests an eco-driving smartphone APP, which provides warnings to drivers to mitigate aggressive driving behaviors, thus reducing vehicle emissions. To this end, the eco-driving APP is developed in a smartphone with the Android platform, which provides real time warnings to drivers on their driving behaviors that are out of the threshold range, which is defined based on the concept of Vehicle Specific Power (VSP) distributions. It is then evaluated by collecting the instantaneous driving activity and the associated emissions data of a test vehicle equipped with a portable emission measurement system (PEMS) embeds with an on-board Global Positioning System (GPS) logging device, which records the vehicle’s instantaneous position and speed, and the associate emissions. It is shown from the study that with the warnings provided by the eco-driving APP, the driving behaviors shifts to the driving patterns, which leads to reductions in vehicle emissions. The CO,CO2 and NOx emissions are reduced substantially, whereas the HC emissions is increased.

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    Detection of Traffic Operation Evaluation Parameters Based on Video at Urban Signalized Intersections
    CAO Qian-xia, LUO Da-yong,WANG Zheng-wu
    2015, 15(6): 60-66. 
    Abstract ( )   PDF (2134KB) ( )  

    Intersection traffic operation evaluation parameters, such as queue length, delay, are difficult to be detected directly. A method is presented to synthetically detect intersection operation evaluation parameters based on video processing. First, the queue vehicles are quickly detected by introducing selective background update mechanism for block- level background subtraction combined with block- level frame difference. Then, the first and the last queue vehicles position can be determined by using virtual parallel line, and the number of vehicles queuing can be detected by combining the first and the last queue vehicles tracking with the virtual loop count near the stop line, as a result, other traffic operation evaluation parameters, such as delay, stop times, also can be gained. The test result indicates that the method can effectively detect multiple parameters simultaneously, also can effectively improve detection accuracy rate. Compared with the actual value,the mean error of measured parameters value is less than 5% which can better meet the need of intersection operating performance evaluation.

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    Calculation and Analysis of the Traffic Parameters of Vehicles Based on the Wide-area Drone Video
    ZHOU Yu-yang,GONG Yi,YAO Lin, LI Xiao-yong
    2015, 15(6): 67-73. 
    Abstract ( )   PDF (1520KB) ( )  

    The video based traffic parameters extraction has great significance in intelligent transportation systems. For the drone video, a new method of the traffic parameter extraction is proposed in this paper. The correction algorithm of the wide- angle lens of the drone is established for eliminating the video images distortion of the intersection. The relation between the image coordinate and the true coordinate is built. Then the frame difference algorithm is used to obtain the traffic parameters of the vehicles, such as the speed, the acceleration and the distance headway. The high accuracy and feasibility of the algorithm is proved by the comparison of the real parameter, the parameter from this paper and that from the software. Finally, an example is given to verify the practicality of this method as well as to analyze the velocity regulation during the vehicles passing the intersection.

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    Multiple Information Fusion-based Vehicle Tracking in Complex Environment
    LIU Yang,WANG Zhong-Li, CAI Bai-Gen
    2015, 15(6): 74-81. 
    Abstract ( )   PDF (1585KB) ( )  

    The vehicle tracking at intersection environment is affected by vehicle scale change, occlusion, vehicle queue and dissipation. To solve the problem, a reinforcement algorithm is proposed by using the rotation robustness and scale-invariant characteristics of SIFT feature, combing with region color histogram to track vehicle in scale change and occlusion situation. This paper also establishes criteria for vehicle separation and integrates clustering algorithm to detect and track departing vehicle. The experiment result shows that compare with traditional algorithm, the proposed algorithm provide more robust and more accurate result in multiple traffic scenes.

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    Driving Speed Behavior Clustering for Commercial Vehicle Based on Connected Vehicle Data Mining
    SUN Chuan,WU Chao-zhong,CHU Duan-feng,DU Zhi-gang,TIAN Fei
    2015, 15(6): 82-87. 
    Abstract ( )   PDF (1177KB) ( )  

    In order to take full advantage of mass connected vehicle data from transportation enterprise and find potential laws of driving behavior characteristic, the parameter of driving behavior characteristic are extracted based on the data. Then eight parameters of driving behavior characteristic transform into several aggregate variables of specific driving behavior information based on factor analysis, and driving behavior for commercial vehicle is analyzed by hierarchical clustering in Jiangsu province. Results show that driving behavior for commercial vehicle can be divided into four classes reasonably, such as speed changing, speeding, deceleration, acceleration. Particularly, drivers of speed changing have other driving behaviors and the levels are high too, and they are high-risk drivers, as an important factor of influence road traffic safety, so transportation enterprises could monitor them specially. Research results are of positive significance to improve the monitoring capability of drivers for commercial vehicle.

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    A Cooperative MAC Protocol in High Dynamic Transportation Network
    ZHANG Yan-kang, ZHANG Bei-bei, ZHANG Hai-yang
    2015, 15(6): 88-93. 
    Abstract ( )   PDF (1563KB) ( )  

    Vehicular Ad Hoc Network can improve traffic safety and efficiency, and it attracts close attention from academia and industry. However, the features in special VANETs scenario, such as highly dynamic topology, high traffic density, unstable links, and so on, cause that it is hard to maintain the reliable data dissemination. Based on the existing MAC layer protocol research results of Ad Hoc network, associating with the special scenarios of VANET, a novel distributed TDMA algorithm named C-T-MAC is designed, and it introduces the concept of cooperative communication. When the transmission between source node and destination node fails, destination node could accept the help of neighbor nodes in idle time slot. Through this can increase the network throughput and the reliability of data. At last, the proposed algorithm in NS- 2 simulation platform is verified. The simulation results show that the algorithm can improve the reliability of information and the utilization of slot in a certain extent.

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    Multi-objective Optimization for Double Stack Train Loading Problem
    LANG Mao-xiang,ZHOU Xue-song,SUN Yan
    2015, 15(6): 94-100. 
    Abstract ( )   PDF (1454KB) ( )  

    To improve safety measures of loading containers on double- stack train and ensure its normal operation, this paper develops a multi-objective optimization model that focuses on a number of practical requirements including the center-of-gravity height of a loaded car and load balance considerations. A lexicographic goal programming approach is used to address different priorities for potentially conflicting objectives and constraints. To minimize the center-of-gravity height, a linear-fractional programming technique is adopted to transform the corresponding generalized mixed integer fractional problem into a sequence of mixed integer linear sub problems. The computational results of the experimental cases indicate that the proposed multi-objective optimization method can maximize the number of the TEUs loaded on the double stack train, and meanwhile lower the center-of-gravity height of the loaded cars and their weight differences, and performs superior application value.

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    The Robust Model for Line Planning Problems of High Speed Passenger Train
    PU Song,WANGWen-xian,CHEN Ding-jun,LV Hong-xia
    2015, 15(6): 101-106. 
    Abstract ( )   PDF (1274KB) ( )  

    The estimated demand data are usually unreliable due to the actual demand, and train line planning based on estimated demand data might not match the actual demand. Assumes that each actual demand lies in an interval specified by mean value and peak value, a robust optimization model is built and translated into a linear mixed integer programming model. And the Lagrangian relaxation algorithm is developed according to the model structure. Then the original problem is decomposed into much simpler subproblems through relaxing the coupling constraints. According to the increment rate of the objective value (corresponding the model for determined passenger demand), the solution of its inflection points is the robust solution. Finally, the model is tested on the Wuhan- Guangzhou high speed railway in China, and a good solution can be achieved with an average gap of 5.04%. The result shows that the robust solution can balance the passenger demand fluctuation and line planning well.

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    Forecast of Passenger Flow Distribution among Urban Rail Stations Considering the Land-use Matching Degree
    YAO En-jian,LI Bin-bin, LIU Sha-sha,ZHANG Yong-sheng
    2015, 15(6): 107-113. 
    Abstract ( )   PDF (1696KB) ( )  

    Conventional passenger flow distribution forecasting models for urban rail transit rarely consider the impact of station surrounding area' s land-use, which results in models' accuracies decline dramatically when the land- use around stations changes, so it is necessary to establish the passenger flow distribution forecasting model considering the land-use and their matching degree. First, based on clustering analysis, the matching degree of land-use (MDLU) is defined as an indicator to reflect the correlation between the stations' land-use and passenger flow distribution. Second, the urban rail passenger flow distribution forecasting model is established based on the disaggregate theory, in which, the effects of station surrounding area' s land- use, MDLU, attraction of destination, travel time and etc. on destination choice behavior are considered. Finally, the passenger flow data collected from Guangzhou metro system is used for the case study, and the result shows that the mean absolute errors of the proposed model are successfully limited to 29.30 and 29.52 respectively when the land-use has no-change or change, which demonstrates that the forecasting accuracy of proposed model is satisfactory.

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    Strategy Analysis for Delayed Fights Pushback Based on Improved Discrete Differential Algorithm
    ZHAO Xiang-ling,TANG Jian-xun, LU Fei, HAN Bo
    2015, 15(6): 114-120. 
    Abstract ( )   PDF (1510KB) ( )  

    Traffic congestion becomes a serious issue in busy airports, which results in extra expense for airlines and long waiting time for passengers. Based on the ACDM, the theory of virtual queue is introduced with a given pushback rate, and the collaborative process of aircraft pushback decision is designed. Aircraft would be kept waiting in stands instead of on the taxiway, which not only relieves airport traffic pressure, but also reduces flight delays and increases the profits of airlines. Two strategies of minimum passenger waiting time and minimum pushback waiting cost are proposed. And the calculation approach of delay cost and relative constraint factors are presented. Five cases of real flight history data are analyzed as different test scales (small, medium and large), and solved by a modified pointer- based discrete differential evolution algorithm. The results show that sorting flights in the virtual queue could reduce passengers waiting time by 5.15%~12.66%, and airlines pushback waiting cost could be saved by 19.16%~26.0%.

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    Mechanisms of Congestion Propagation in Air Traffic Management Based on Infectious Diseases Model
    DAI Xiao-xu,HU Ming-hua,TIANWen,HU Bin
    2015, 15(6): 121-126. 
    Abstract ( )   PDF (1672KB) ( )  

    Previous researches mainly focused on the superficial aspects such as the network distribution and real-time data observation of the congestion propagation, on that account, this paper seeks to explore the scientific pattern of the evolution of air traffic congestion propagation. According to the similarity of the process between air traffic congestion propagation and transmission of infectious disease and referring to SIR model of infectious disease, an air traffic congestion propagation model is presented. Phase trajectory analysis and parameter analysis are used to achieve the propagation tendency and threshold value of the congestion. The effects of influence factors and dissipation factors on the propagation process are also explained. Compared with actual delay data from Atlanta and Baiyun airports, it turns up that the model just right fit the basic congestion process. However, all types of factors need to be adjusted according to the practical situation so as to not be able to form fixed values. For more complicated congestion process, new parameters should be involved.

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    Psychological Carrying Capacity of Non-motorized Traffic Environment in Historical Districts
    WANG Qiu-ping,HAN Xia
    2015, 15(6): 127-132. 
    Abstract ( )   PDF (1305KB) ( )  

    Travel by non-motor vehicles accounts for a big proportion in historical districts, but because of the limitation of the space scale and road network pattern of historical districts, non- motor vehicles drive chaotically with pedestrians and motor vehicles, which results in a poor travel environment. Through the practical survey in Shuyuan historical district in Zhengzhou, Gulou historical district in Kaifeng and Dongxinanyu historical district in Luoyang , the influence factors and evaluation index of psychological carrying capacity of non- motorized traffic environment in historical districts is studied, and its evaluation models of negative binomial distribution is established by introducing tolerance thresholds. According to the data of Shuyuan historical district in Zhengzhou and Gulou historical district in Kaifeng, which show that the study method is feasible, also suitable for accurately evaluating the non- motor vehicle lane capacity and optimizing the road cross- section, to improve the environment of non- motorized traffic for a sustainable development in historical districts.

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    Aircraft Flight Path Detection and Risk Identification in Landing Phase
    YUE Ren-tian, JIAO Yang, ZHAO Yi-fei
    2015, 15(6): 133-139. 
    Abstract ( )   PDF (2384KB) ( )  

    The landing is the most dangerous stage of the flight. At present, the risk recognition in landing stage only rely on visual observation of tower controller. In general aviation training when the pilot is unskilled and contains frequently taking off and landing, it is very difficult for visual observation to completely handle the situation, therefore it contains a huge safety risk. In this paper, the data of video surveillance is used to track the landing of aircraft, a small target segmentation algorithm is proposed which is suitable for the complex background at the same time; and based on this, the operational risk of the landing process is further identified. It is verified by the video surveillance data from different point of view, the algorithm can achieve the tracking of aircraft landing path under complex background, judgment of landing moments and accurate recognition of dangerous sliding path, which has important practical significance to ensure flight safety.

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    Multiple Tractor-and-trailer Crossed Scheduling Optimization under Hybrid Mode
    YANG Zhen-hua, XU Qi, CHEN Zong-xing, JIN Zhi-hong
    2015, 15(6): 140-146. 
    Abstract ( )   PDF (1787KB) ( )  

    Using multiple vehicles is the new trend of tractor-and-trailer transportation development. Tractors with high load capacity can pull various trailers under its load capacity restriction. We call this phenomenon crossed tractor-and-trailer scheduling. To study the advantages of this transportation mode and the effects of the distribution of customers, considering its feature, a multiple tractor-and-trailer crossed scheduling model is established under hybrid mode, which is combined of hub-and-spoke mode and network mode. Then an appropriate simulated annealing algorithm is developed to solve the problem. The result is compared with those got by three existing tractor- trailer matching strategies. It shows that the model and algorithm are effective and multiple tractor-and-trailer crossed scheduling has advantage in saving cost. At last, the four strategies are used to solve converted Solomon classic numerical examples, analyzing the effect of the distribution of customers on objective function value. That customers are distributed in clusters can lower total operation cost in tractor-and-trailer transportation system. The conclusions can provide decision support for the operators.

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    Operational Capacity on Freeway Bottleneck Segment
    WU De-hua, QIU Zhi-Jun
    2015, 15(6): 147-153. 
    Abstract ( )   PDF (1391KB) ( )  

    The traffic congestion can cause operational capacity drop phenomenon on freeway bottleneck segment. To reveal the capacity diversification regular pattern, the asymmetric driver behavior theory is used to improve the Newell car-following model. The improved car-following model is calibrated and implemented in field data simulation. By 12 simulation scenarios and field data analysis, the results show that the improved Newell car-following model can increase accuracy in estimate the bottleneck operational capacity compared to the model that Highway Capacity Manual (HCM2010) provided. The traffic congestion due to the lane drop is analyzed, the operational capacity varied in condition close different lane and number of lanes, then the varied value is figured out. The operational capacity on major lane bottleneck segment decreases by changed the flow on on- ramp and off- ramp in range of certain flow change, and the most decreased value is calculated. In conclusion, the results can provide reference for migrate congestion on freeway bottleneck segment.

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    Probability-based Delay Model for Signalized Intersections with A Short Right-turn Lane
    TIAN Zong-zhong, MAYan, GAO Hong-yan, SU Jie
    2015, 15(6): 154-160. 
    Abstract ( )   PDF (1581KB) ( )  

    This paper documents the modeling of vehicle delays at signalized intersections with a short right-turn bay which is commonly seen in urban traffic. The model is developed considering the stochastics of traffic volume variation which can result in uncertain blockage occurrences to the short right-turn bay. The proposed model enhances the existing methodologies documented in the U.S. Highway Capacity Manual 2010 (HCM 2010) which treats the short bay as an exclusive full lane. The model incorporates probabilistic theories and intersection characteristics, thus providing an improved approach to delay estimation by considering the short-bay storage length, traffic flow rate, and signal timing. The proposed model is validated using the SimTraffic microscopic simulation model, which is calibrated using field data obtained at a realworld intersection site. Based on the model, it is found that the short-bay length strongly influences the rightturn vehicle delays. In addition, allowing right-turn-on-red (RTOR) can ease the over-saturation problem and reduce the approach delay substantially, especially when the short-bay length is less than 2-vehicle storage length.

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    A Method for Estimating Road Congestion Probability and Its Application in Urban Traffic Operation Evaluation
    ZHANG Peng, ZHANG Xiao-song, LEI Fang-shu, ZHU Guang-yu,GUO Ji-fu,Quan Yong-shen
    2015, 15(6): 161-169. 
    Abstract ( )   PDF (1853KB) ( )  

    First, this paper proposes and validates that travel time index (TTI) of vehicles have a uniform probability distribution mode under different link speed. Then, it proposes a model which describes how the distribution parameters vary with link speed. On such basis, a novel method of estimating congestion probability for traffic operation evaluation is presented. Probability distribution parameters are obtained based on road speed, then different congestion probability could be got according to probability distribution. The proposed models and method are used to solve the insufficient problem of existing traffic operation evaluation methods of big cities in China. The result shows that the given method can address the impact of link length on evaluation result and significant volatility of microscopic evaluation entailed by the existing methods. The proposed theoretical models hold broad application prospects in the field of traffic performance analysis.

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    OD Estimation Based on Turning Movement
    LI Rui-min, CHEN Xi-yi, ZHANG Rui-bo
    2015, 15(6): 170-176. 
    Abstract ( )   PDF (1393KB) ( )  

    Origin- Destination Matrices, also called OD Matrix, is an important basic for the transport planning and traffic management. A procedure is proposed to estimate the OD matrix based on the abundant precise vehicle trajectory data. The turning movement and link count are provided by the automatic number plate recognition (ANPR) data. An OD estimation method is proposed based on the General Least Squared Model (GLS). Using S-Paramics simulation platform, Nguyen-Dupuis Network and a real city road network are used to compare the estimation results of different circumstances: real OD known or unknown, two different inputs(the turning movement and the link count), and different rates of measurements. The results show that the turning movement can improve the accuracy of OD estimation.

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    A Simulated Annealing Heuristic for the Consistent Vehicle Routing Problem
    LIU Heng-yu, RU Yi-hong
    2015, 15(6): 177-183. 
    Abstract ( )   PDF (1846KB) ( )  

    According to the“service consistency”characteristics of the consistent vehicle routing problem, a template-based simulated annealing heuristic (TSA) is proposed to look for better solutions, this algorithm can be divide into two stages: in the first stage, we get the template routes, and in the second stage, the template routes serve as a reference to determine the daily vehicle routing schedules. The simulated annealing heuristic is applied in both stages to get optimal solutions. Based on two small-and middle-scale benchmark data sets, numerical experiments are conducted to test the TSA and then the results are compared to ConRTR’s and TTS’. It can be seen that both the“service consistency”indicators in these two experiments are improved. Therefore, the results prove that by using TSA to plan vehicle delivery routes, not only the operating cost is reduced but also higher service quality obtained.

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    Traffic Flow Parameter Prediction Based on Granular Computing
    DING Hong-fei,LIU Bo,LUO Xia,LI Yan-hong
    2015, 15(6): 184-189. 
    Abstract ( )   PDF (1244KB) ( )  

    Traffic flow parameter prediction is the foundation of traffic flow guidance system and traffic information display system. This paper takes information granule as basic analysis unit, and provides a brand new approach to build fuzzy time series model aiming to neutralize original model’s defects. Based on digging internal correlations of the data, this new approach analyzes dynamic regional interval length under the influence of time variables. This approach is characterized as Gath- Geva fuzzy clustering algorithm based on the segmentation of time series, where the information granule serves as data units is analyzed by granular computing, from which the traffic flow parameters’fluctuation trends are captured. Experimental results show that traffic flow parameter prediction based on granular computing gives reasonable confidence interval and is more reliable than the original. The new approach is helpful for further traffic state dynamic analysis.

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    Day-to-day Traffic Flow Assignment Model Considering Departure Time Adjustment
    CHEN Ling-juan,WANG Dian-hai,DAI Jiong
    2015, 15(6): 190-196. 
    Abstract ( )   PDF (1412KB) ( )  

    In order to study the evolution law of day-to-day traffic flow under non-equilibrium caused by incident, adjustment of departure time is introduced into consideration. With the pursuit of maximizing the arrival probability, daily transfer model for departure time is established; prospect theory is adopted to describe travelers’bounded rationality, and daily transfer model for path is established based on paths prospect value under the reference point of travel time budget. Finally, a numerical example is adopted to verify the model and algorithm. The results show that the daily path presents convex function, and with the increase of travel days, all paths flow distribution tend to be stable over time; Comparing with nonconsidering of time adjustment, the results show that the network stability requires longer days, tends to a larger amplitude, and reaches a new equilibrium finally.

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    Improved Algorithm for Stochastic Network Connectivity Reliability
    FANWen-bo,WANG Jia-wei,YANG Cheng
    2015, 15(6): 197-204. 
    Abstract ( )   PDF (1541KB) ( )  

    As the basic indicator of network reliability, connectivity reliability analysis provides theoretical basis for practices of traffic accident prevention, post-disaster reconstruction, operational maintenance, etc. The computation of connectivity reliability, however, is a typical NP-hard problem. In order to improve the computing accuracy and efficiency of large-scale network application, an improved algorithm (called Target_Order) is proposed based on k- shortest path algorithm and ORDER algorithm (which is used to produce the most probable network states). Chengdu metro network (year of 2020) is selected as an example to explore the impact of algorithm parameters and illustrate the considerable advantages of the proposed algorithm against traditional ORDER algorithm in terms of computational accuracy and efficiency. The improved solution algorithm can be also applied to connectivity reliability evaluations of other transportation networks (e.g., railway and highway).

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    Forecasting of Entering Passenger Flow Volume in Beijing Subway Based on SARIMA Model
    WANG Ying, HAN Bao-ming, Zhang Qi, Li De-wei
    2015, 15(6): 205-211. 
    Abstract ( )   PDF (1574KB) ( )  

    Based on the inbound traffic data of Beijing subway from May 2013 to July 2013, this paper analyzes and summarizes the fluctuation of Beijing subway inbound traffic data from weekly cycle. In the process of modeling, the seasonal time series (SARIMA) model is used. Using the model to predict the traffic flow in Beijing subway, the forecast results can accurately describe the change trend of the traffic flow in Beijing subway station, the average error is 0.3%. The result shows that the model is suitable for the prediction of the traffic flow in the Beijing subway. Based on the forecast model results, further analysis of the characteristics of the entering passenger flow volume is analyzed. And the reference suggestions are provided for the further optimization of the layout of the station facilities, the flow line of the organization and the efficient and safe operation of the subway.

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    Endurance Time of Pedestrians Crossing at Signalized Intersection of Beijing
    ZHANG Zhi-yong, HAO Xiao-yun,WANG Dong,WANG Da
    2015, 15(6): 212-219. 
    Abstract ( )   PDF (1941KB) ( )  

    In order to ensure the efficiency of the vehicles at signalized intersection, many pedestrians crossing environments have been destroyed in Beijing, "Chinese style of crossing road" came into being. Based on the research on the endurance time of pedestrians crossing at signalized intersection of Beijing can ensure the safety of the pedestrian crossing and has a great significance on improving the efficiency. Moreover, it has important practical significance on promoting the strategy of "equity priority and give consideration to efficiency" and improving the efficiency of urban traffic system. According to the characteristics of the current traffic of Beijing, the paper focuses on the pedestrians crossing illegally who arrive at the signalized intersection crosswalk waiting area during the red light. The paper uses both video survey and manual survey to collect 9,554 samples of endurance time. The paper establishes Weibull distribution parameter model of pedestrians crossing endurance time at signalized intersection. The results show that environmental factors, pedestrians characteristics, travel time, traffic conditions and road environment have great influence on the pedestrians crossing endurance time.

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    The Exploration of Time-headway Characteristic and Operation Status on the Bus Route
    ZHANG Jian,DING Jian-xun,LONG Jian-cheng,SHI Qin
    2015, 15(6): 220-226. 
    Abstract ( )   PDF (2448KB) ( )  

    The bus route is a seemingly simple but complicated traffic system, and several random factors cause various time- headway patterns and operation state on the route. The time- headway is affected by vehicle capacity, departure interval and arrival rate of passengers. This paper incorporates vehicle capacity, departure interval and arrival rate of passengers into an improved time-headway model. Using the model, the phase diagram of bus route and mutual evolutionary process are identified and such four distinct states consist of regular state, transient state, pairing and clustering state, which gives a deeper understanding of the bus route system.

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    Advance Distance of Speed Limit Sign for Crosswalk of Urban Road at Night
    CHENG Guo-zhu,QIN Li-hui,XU Liang, GUO Yu-feng,MO Xuan-yan
    2015, 15(6): 227-231. 
    Abstract ( )   PDF (1208KB) ( )  

    In order to ensure pedestrian safety at night, the advance distance of speed limit sign is conducted for crosswalk of urban road at night. Through an experiment of driver distance recognition, changing regulation of driver recognition distance at night vs. driving speed and average luminance is studied. Relationship model among driver recognition distance at night, driving speed and average luminance is established. Moreover, calculation method of advance distance of speed limit sign for crosswalk of urban road at night is presented based on discriminating conditions of safe driving. Then suggested values of advance distance of speed limit sign are given corresponding to different pavement type, speed limit value and average luminance. Results show that advance distance of speed limit sign for crosswalk of urban road should be determined by speed limit value and average luminance. The lower speed limit value is and the higher average luminance is, the more advance distance of speed limit sign should be. Applying the presented method to set speed limit sign for crosswalk at night, it can ensure crossing pedestrian’s safety.

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    Forecasting Travel Demand for Combined Bus and Airline Mode: A Case Study of Hubei Province
    ZHOU Juan, LI Zhi-Chun
    2015, 15(6): 232-237. 
    Abstract ( )   PDF (1438KB) ( )  

    Based on the disaggregate choice theory, a multinomial Logit model is established to investigate the mode choice behavior of intercity travelers among combined bus and airline mode, bullet train to high speed rail, and bus to high speed rail. Stated preference (SP) survey is conducted for four city pairs from Xiaogan, Suizhou, Xiangyang, and Shiyan to Shanghai, respectively. The Logit model is calibrated by the survey data for the four city pairs, and is then used to ascertain the key factors affecting travelers’mode choice and to estimate the modal split of intercity transportation market. The findings show that the access/ egress time and the total monetary travel cost play an important role in the mode choice behavior of intercity travelers.

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