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25 December 2010, Volume 10 Issue 6 Previous Issue    Next Issue
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Decision-making Forum
Forum about Comprehensive Transportation System
Intelligent Transportation System and Information Technology
Systems Engineering Theory and Methods
Cases Analysis


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Decision-making Forum

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Future Development of Integrated Transportation in China JIA Shun-ping 2010, 10(6): 1-10 .  Abstract ( )   PDF (1952KB) ( )   The Sixth Advanced Forum on Transportation of China sets its theme as “future development of integrated transportation in China”, relates to theory and method of regional integrated transportation, theory and method of low carbon transportation systems, development and application of intelligent transportation systems and so on. Recalling the development of integrated transportation of the “11th Five-Year”, and looking forward to development prospects of the “12th Five-Yea”. It is important to strengthen the planning and construction of the integrated transportation network and the hub bases on continuing to improve transportation access. Meanwhile, studies the development of China’s high speed railway, transportation structure and growth mode transformation, civil aviation, waterway, intelligent transportation system and urban traffic. And analyzes the problems and achievements, points the opportunities and challenges, discusses the development goals and ideas. Provides reference for future development of integrated transportation in China Related Articles | Metrics

Forum about Comprehensive Transportation System

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Urban Transportation and Management——The Scientific Development of Urban Transportation in China LIU Xiao-ming 2010, 10(6): 11-21 .  Abstract ( )   PDF (2209KB) ( )   Urban transportation plays an important role in urban development. A convenient, efficient and smooth transport system is an important guarantee for sustainable urban development, and a measure of an important indicator of the level of urban modernization. Urban transport problem is the concentrated reflection of multiple conflicts in urban development. Different traffic problems can not be solved simply by applying the same mode. The paper summarizes the status of Chinese urban transport development and problems. In accordance with the concepts of humanities, science and technology, green and low carbon, urban transport development strategies are suggested for Chinese cities based on international experiences in urban transport development. References | Related Articles | Metrics

Intelligent Transportation System and Information Technology

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Parallel Systems for Urban Rail Transportation Based on ACP Approach NING Bin, WANG Fei-yue, DONG Hai-rong, LI Run-mei, WEN Ding,LI Li 2010, 10(6): 22-28 .  Abstract ( )   PDF (1115KB) ( )   This paper presents a novel parallel system for Urban Rail Transportation (URT) based on the Artificial Systems、Computing Experiments and Parallel Execution (ACP) method, which is proposed to address issues on safety, efficient and reliability of the operation of URT. An analysis of traditional simulation software demonstrates the necessity of building dynamic, overall and real parallel systems for URT. Artificial systems are considered first which are called Artificial URT (AURT) systems. By performing numerical computational experiments on AURT systems, the systems behavior are studied and detailed operations identified, finally achieving parallel control and management of the real URT systems via parallel operation and alternative realization. This new approach consistent with realistic operations of real URT systems would lead to a set of recommendations and strategies that would improve the overall functionality of the comprehensive transportation system. References | Related Articles | Metrics

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Research on Digital Railway System Architecture SHI Tian-yun, WANG Ying-jie, LI Ping 2010, 10(6): 29-33 .  Abstract ( )   PDF (944KB) ( )   The digital railway is a new railway information system, which researches digitization of the railway infrastructure, transportation equipment and railway environment based on geographical information system(GIS), global position system(GPS), remote system(RS), information system, internet of things, virtualization, information integration, etc. to realize total management and vivid indications of the railway transportation and service resource. It modifies and perfects the current railway information system, have effect on improving the level and image of railway management and service, and assuring the transportation safety. In this paper, the main research contents and key technologies are analyzed, general framework and standard systems of digital railway are given, the structure of the GIS sharing platform is designed. These have important instruction function on construction of digital railway. References | Related Articles | Metrics

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Iterative Learning Based Adaptive Traffic Signal Control ZHENG Yi-chen, ZHANG Yi,HU Jian-ming 2010, 10(6): 34-40 .  Abstract ( )   PDF (1211KB) ( )   Iterative learning control (ILC), as a branch of data-driven control, has obtained plentiful achievements both at theoretical research and practical application over the past two decades. Taking the traffic signal control system as a plant system, the paper introduces the idea of the ILC and fuzzy logic to design an adaptive data-driven traffic signal controller to improve the capacity of the intersection. The key rule of the signal control logic is described by fuzzy iterative theory, and the control strategy can adapt itself to the changing of traffic flow by iterative learning and handle the uncertainty and randomness in traffic system by fuzzy logic, so as to avoid the modeling of complex transport system and take advantages of data-driven on non-model control. Finally, the proposed method is testified to be applicable and effective based on the simulation results by VISSIM. The simulation result indicates that the effect of the proposed method is more effective than the fixed and actuated control approaches. References | Related Articles | Metrics

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Mixed Traffic Order Degree Model of Urban Signalized Intersection LIU Jin-guang, LIU Xiao-ming, KONG Qing-feng,YU Quan, RONG Jian 2010, 10(6): 41-47 .  Abstract ( )   PDF (1054KB) ( )   Mixed traffic is one of the most remarkable characteristics of transportation in Chinese cities. In order to study the phase strategies of urban signalized intersection and carry out the mixed traffic simulation of the intersection, this paper proposes a novel definition of the mixed traffic order based on the “time-space resource using” of the intersection, and establishes the mixed traffic order model. It proposes the conflicting area model based on the space resource, and the conflicting time model based on the time resource of the intersection， and the order degree of the mixed traffic is taken as a new index of evaluation for the signal control optimization. Finally, it takes the order degree and the vehicle delay as the indexes of evaluation for the optimization, uses the simulation method. A real signalized intersection is illustrated to get the optimal strategy, and it gets an optimal result after an optimal process. The result indicates that the optimal strategy evaluated by the order degree of mixed traffic and the vehicle delay is better than the former strategy evaluated by the vehicle only，and it fits to describe the mixed traffic phenomenon of China. References | Related Articles | Metrics

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Traffic Image Fusion Algorithm Based on Non-Sampled Contourlet Transform MA Wen-jia, QU Shi-ru 2010, 10(6): 48-52 .  Abstract ( )   PDF (1633KB) ( )   The TV monitor is an important part of the intelligent transportation monitoring system. Its purpose is monitoring the vehicles, pedestrians, and environment through the video traffic image processing. According to the non-sampled Contourlet transform with the characteristics of multi-resolution, multi-directional, and translational invariance, the paper proposes a multi-focus image fusion algorithm based on the non-sampled Contourlet transform. The fusion strategy is that the low-frequency coefficient is used to calculate the average and the high-frequency coefficients are taken the greatest regional characteristics weight based on neighborhood, brother and parent information. After comparing the present method with the wavelet transform, the ridgelet transform, and Contourlet transform, the experimental results prove that the method mentioned in this paper can achieve a better fusion of results and can improve the image quality and meet the requirements of intelligent transportation control system. References | Related Articles | Metrics

Systems Engineering Theory and Methods

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Cost-Time Minimization in a Transportation Problem with Fuzzy Parameters: A Case Study CHAKRABORTY Ananya,CHAKRABORTY M. 2010, 10(6): 53-63 .  Abstract ( )   PDF (1163KB) ( )   In real world applications the supply, the demand and the transportation cost per unit of the quantities in a transportation problem are hardly specified precisely because of the changing economic and environmental conditions. It is also important that the time required for transportation should be minimum. In this paper a method has been proposed for the minimization of transportation cost as well as time of transportation when the demand, supply and transportation cost per unit of the quantities are fuzzy. The problem is modeled as multi objective linear programming problem with imprecise parameters. Fuzzy parametric programming has been used to handle impreciseness and the resulting multi objective problem has been solved by prioritized goal programming approach. A case study has been made using the proposed approach. References | Related Articles | Metrics

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Route Choice Behavior Model with Guidance Information GAO Feng, WANG Ming-zhe 2010, 10(6): 64-69 .  Abstract ( )   PDF (938KB) ( )   Using modeling and simulation methods, the driver’s route choice behavior under guidance information is explored based on the combination of the decision field theory (DFT) and Bayesian theory. First, based on the Bayesian theory, a road condition dynamic updating model is presented in light of the guidance information and the driver’s previous travel experiences. Then, the route choice behavior model under guidance information is formed by the fusion of the process-oriented vehicle dynamic route choice model and the road condition dynamic updating model. The developed model describes a driver’s propensity to comply with received guidance information in terms of the interaction between perceived unreliability of the information, his previous travel experiences, preference for different road alternatives, decision-making speed/quality, and route selection criteria. The simulation results show that the combination of the DFT and Bayesian theory can effectively explain the driver’s travel dynamics behavior. References | Related Articles | Metrics

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Trip Chain’s Activity Type Recognition Based on Support Vector Machine YANG Yang,YAO En-jian,YUE Hao, LIU Yu-huan 2010, 10(6): 70-75 .  Abstract ( )   PDF (780KB) ( )   This paper focuses on support vector machine (SVM) based trip chain’s activity type recognition. First, the time-series location information of person trip is processed to obtain the trip chain elements including moving processes and activities, and the activity options are extracted from the geographic information system (GIS) around the activity sites. Second, the activity features are drawn from spatio-temporal factors of trip chain to serve as the input feature vector of classifier. A SVM based one-to-one classifier is established and the method of one-to-one classifier voting is adopted to decide the most likely activity type from the activity options. Finally, the classifiers are trained with simulation data based on the gaussian radial basis (RBF) kernel function and the multilayer perception (MLP) kernel function respectively, and then examined by cross validation. The result shows that in the one-to-one classifying scheme, the highest and lowest right recognition rate with RBF are 99% and 62%, and the corresponding results with MLP are 97% and 54%, respectively. References | Related Articles | Metrics

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Safety Evaluation for Freeway Exit Ramp Based onSpeed Consistency GUO Tangyi, DENG Wei,LU John 2010, 10(6): 76-81 .  Abstract ( )   PDF (803KB) ( )   Speed differential has direct relationship with road safety. Conventional speed consistency measures draw sample data from independent population that follows a normal distribution. These methods may fall into ecological fallacy and overestimate the safety level of road elements. After deducing the relationship between the difference in operating speed and85( ), the 85th percentile value of individual speed reduction, this paper recommends 85( ) and speed reduction rate 85( )R is used to evaluate ramp safety. Point speeds of individual vehicle at freeway diverge area, upper ramp, and lower ramp are collected by radar guns. Safety performance of 37 exit ramps are appraised using three different measures, namely, , 85( ), and 85( )R. The results show that 85( ) is 1.42 to 2.02 times of , and that the evaluation result of 85( )R is between the other two. The measure 85( )R considers not only individual speed but also the base speed on upstream element, which avoid the pitfalls of ecological fallacy and overestimation possessed by conventional measures. It is a safer and reasonable measure that should be adopted in practice. References | Related Articles | Metrics

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Train Grade Resistance Calculation Modification Model Based on Measured Data DING Yong,ZHOU Fang-ming, BAI Yun, LI Rui-jie, MAO Bao-hua 2010, 10(6): 82-88 .  Abstract ( )   PDF (934KB) ( )   In order to make train movement simulation have good correlation with practical railway transportation, the comparison between calculation results based on train traction calculation and measured data from Train Running Monitor and Record Device is investigated in this paper. According to the differences between numerical model and actual data, the key cause resulting in the inaccuracy is identified, the impacts of track layout and train formation to the errors of train grade resistance calculation are revealed. A new model is proposed, which can be used to correct the calculation errors based on measured data, through theoretical deduce and experiments. Calculation results of new model and that of initial model were compared with the measured data respectively, and the results show that the former accords with measured data better. The proposed model can describe train dynamics more accurately, the average of the calculation errors decreases from 14 percent to 5 percent. Now, the new model has been successfully applied into Energy-Efficient Freight Train Operation Guidance System with Diesel Locomotive. References | Related Articles | Metrics

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Optimization of Two-Stage Port Logistics Network of Dynamic Hinterland Based on Bi-level Programming Model JI Ming-jun, HE Mao-ying 2010, 10(6): 89-94 .  Abstract ( )   PDF (850KB) ( )   The regional logistics based on port and its regional economic react on each other and develop in unison. This paper studies the two-stage port logistics network, the first one is the sea routes system between any two ports, and the second one is the network of the transportation system between each port and its economic hinterland. Based on the conditions of dynamic hinterland, the study proposes a bi-level programming model with the upper objective of the total transportation cost in the regional port cluster and the lower objective of the economic benefits for individual port. The competitiveness of the port, the demarcation of the hinterland, and the traffic capacity are reflected dynamically in the model, which is closer to the real system. The model is transformed into a single-programming model based on the Kuhn-Tucker theory to solve the model. Numerical tests are provided to illustrate the validity of the model and algorithm. Finally, the example is solved by Matlab. The results show that the bi-level model and the algorithm are feasible. References | Related Articles | Metrics

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Forecasting Technology of National-Wide Civil Aviation Traffic WANG Shi-jin, SUI Dong, HU Bin 2010, 10(6): 95-102 .  Abstract ( )   PDF (887KB) ( )   The long-term forecasting of national-wide civil aviation traffic provides basis for the airspace project planning. A gray combination forecasting model is put forward based on the GM (1, 1) forecast model and least squares principle. With the historical data analysis of the national-wide air traffic from the year 1985 to 2008, the forecasting applicability is examined with three different methods, such as the time series forecasting, regression forecasting, and neural-network forecasting. After analyzing the characteristics of Chinese national-wide civil aviation traffic data and contrasting forecasting result, the gray combined forecasting model produces the best effect among these forecasting models. References | Related Articles | Metrics

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Non-Linear Combined Prediction Model of Medium and Long-Term Civil Vehicle Population of China DENG Wen, HU Si-ji 2010, 10(6): 103-108 .  Abstract ( )   PDF (868KB) ( )   With consideration of the economy development tendency in China, a civil vehicle population prediction model is developed based on the space-time theory. First, with the domestic and international experience on vehicle development, the gray Verhulst model is used to describe the vehicle population development tendency and predict the vehicle population in the next 20 years. Second, several social and economical indexes related to vehicle population are selected by comparing the correlation coefficient value, and then the principal component method is used to reduce dimension of the selected indexes and obtain some principal indexes. Based on the econometrics theory, a forecasting model is formulated to predict the vehicle population in the next 20 years. Integrating these two forecasting models, a non-liner combination forecasting model is developed based on the BP neural network. The reliability and accuracy of the linear combination forecasting model are tested by the vehicle data from 2003 to 2007. Finally, the civil vehicle population of China in the next 20 years is predicted again based on the linear combination forecasting model. References | Related Articles | Metrics

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One-Way Traffic Organization Based on Traffic Load and Road Equity LONG Dong-fang, SHI Feng, WANG Ying-zi 2010, 10(6): 109-114 .  Abstract ( )   PDF (741KB) ( )   To improve the utilization of branch roads and alleviate traffic congestion on arterial roads, the optimization approach of one-way traffic organization is proposed from the view of traffic load and road equity. The bi-level programming model is established with the objectives of the portion that road saturation exceeds anticipant saturation and vehicle detour index. The upper model is to obtain the minimum value of objectives by optimizing one-way traffic, and the lower one adopts the equilibrium model to distribute traffic flow. Then, the simulated annealing algorithm is designed to solve the bi-level model. At each iteration step, one of branch road sections with high load is selected for lane reversal. The numerical result shows that one-way traffic organization can reduce the over-saturation portion of road section, however, with the increase of detour index proportion, the potential of reduced degree decreases gradually. References | Related Articles | Metrics

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Optimization Models of Rush Hour Transit System Based on Cournot Behavioral Assumption LIU Ding, HUANG Hai-jun, LI Hua-min, TIAN Qiong 2010, 10(6): 115-120 .  Abstract ( )   PDF (732KB) ( )   Based on Cournot behavioral assumption, with the consideration of passenger travel behavior during rush hour, we investigate transit system optimization. The interval of transit vehicle is assumed to be determined by transit companies, while the total number of vehicle is the result of passengers’ equilibrium riding behavior. Considering demand elasticity, arrival early penalty and congestion in carriages, we propose two optimization models of the rush hour transit system on the base of passengers’ equilibrium riding behavior. The first model aims at maximizing the net benefit of the system, gives the optimal value of the demand realized totally and the number of trains required. The second model maximizes every company’s profit in an oligopoly market regime, determines the optimal time interval of dispatching trains. Numerical results are presented for illustrating analytical results. It is found that, the number of transit company could influence system manifestation, which could be cutthroat competition without government regulation, accompanied by the phenomenon of wasting social resources. References | Related Articles | Metrics

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System Dynamics Model and Simulation of Integrated Price Strategies of Urban Public Transport SUN Guang-lin,WANG Jian, HU Xiao-wei 2010, 10(6): 121-127 .  Abstract ( )   PDF (1040KB) ( )   The price system of urban public transport is composed of travelers, operators and managers，which to be several nonlinear feedback loops with multiple variables. Each integrated price strategy has different influence to different body. The public price system is classified into three subsystems by three bodies: supplying, payoff, demand subsystem. This paper uses system dynamics to develop causality graph, flow graph, and model of public price system based on variables. The integrated strategies are the variations including increase or decline among subsidy from government, new bus owned by operators and price of public. Price scheme is simulated by five situations under high and low level of economic in Harbin. The results show the changing of the subsidies, the profit, and waiting time within predicted period. Selecting social welfare and the ratio of funds usage are to evaluate the influence of differently integrated price strategies. The researches into integrated price strategies have key meaning to make and implement policies of urban public transport. References | Related Articles | Metrics

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Study of Decision Tree Structure of Traffic Mode Choice Based on the Goodness of Fit Measure WEN Hui-ying, ZENG Wen-chuang 2010, 10(6): 128-132 .  Abstract ( )   PDF (690KB) ( )   Nested-Logit model (NL model) is one of the most important models in traffic modal split, based on theoretical basis of the method of traffic modal split for public traffic and private traffic, according to the different factors of people’s first considering in the middle part, the paper constructed virtual traffic modes different from public traffic and private traffic—high-cost and low-cost virtual traffic modes, and analyzed the correlation of alternatives in virtual traffic. the paper also proposed method of choosing the better decision tree structure of traffic mode choice based on goodness of fit measures. According to passenger travel survey data in the example, using SAS software, the paper comparatively analyzed the goodness of fit measure, and the results showed that: the choice probabilities from high-cost and low-cost virtual traffic modes based on the goodness of fit measure can better closer to the survey value. This method is useful in application. References | Related Articles | Metrics

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Distribution Characteristics and Models of Vehicle Specific Power on Urban Expressways SONG Guo-hua,YU Lei 2010, 10(6): 133-140 .  Abstract ( )   PDF (1210KB) ( )   The development of new fuel consumption and emission models creates the need to characterize traffic conditions by using the Vehicle Specific Power (VSP) distribution. However, in the existing transportation engineering, there has been the lack of knowledge of relationships between the VSP distribution and the commonly used traffic parameters, and the lack of models to develop the VSP distribution from traffic parameters. In order to examine how traffic conditions impact the VSP distributions, this study uses large samples of floating car data collected from the expressways in Beijing to associate the VSP distributions with various average travel speeds. After a comprehensive analysis, regular patterns are found between the VSP distribution and the average travel speed. Specifically, when the average travel speed is higher than 20 km/h, the VSP distribution comes close to a normal distribution. The mean of the VSP distribution is the VSP value when cruising at the average travel speed, and the standard deviation could be expressed as a power function of the average travel speed. Based on these findings, a mathematical model for developing the VSP distributions is then derived by using the average travel speed. Finally, a comparative analysis between the estimated and actual fuel consumption demonstrates that the VSP distributions developed by the proposed model are applicable for fuel consumptions estimations. This study indicates a possibility of developing VSP distributions mathematically for different traffic conditions, which can be integrated efficiently with traffic models or data for the real\|time estimation of fuel consumption and emissions. References | Related Articles | Metrics

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Optimal Path Selection Based on Driver’s Preference WEI Zeng-xin, CHEN Jin-lai, LUO Chao-hui 2010, 10(6): 141-144 .  Abstract ( )   PDF (552KB) ( )   Drivers often make route choices according to their preference in our real life. They have different requirements for different path attributes whose values are in the acceptable range rather than a precise value. In this paper, the problem for optimal path selection with driver’s preference is studied and optimal path selection method is put forward to comprehensively reflect preference. Firstly, considering the multi-attribute decision-making method based on possibility degree and interval number’s deviation degree, the author presents an optimization model by minimizing total deviation of driver’s preference from path attribute value and counts out the path attribute weight. Secondly, depending on obtaining comprehensive attribute value of each path, possibility degree matrix and ordering vector are built between paths and the optimal path is found. Finally, an example is given to verify that the path selection method has good feasibility and applicability. References | Related Articles | Metrics

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Single-Mean Signs Appropriate Repetition Intervals Determination by Drivers’ Short-Term Memory XU Ting,SUN Xiao-duan,HE Yu-long,WANG Jun-lei 2010, 10(6): 145-149 .  Abstract ( )   PDF (1350KB) ( )   Traffic signs repetition intervals influence their effects. Large intervals increase the burden of the driver’s mental and small intervals lead to waste of social sources. Large intervals may not reasonable and suitable for reminding drivers. Small intervals will not meet the expectation. Short-term memory characteristics and drivers’ safety performance are applied to locate single-mean signs. In order to explore drivers’ short memory characteristics, 42 samples are selected to participate indoor test in driving simulator. Exponential model is established based on the test performance. Results show that the short term memory decreased by 4% percent in the first 35 seconds and gradually became stable after 35s, decreasing by 3%. Memory accuarcy went down to 50%.Single mean traffic intervals on highway are calculated according to the short-term memory model and different operating speed. References | Related Articles | Metrics

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Microscopic Simulation Modeling and Analysis on Train Inspection Operation in Railway Marshalling Station LI Ji-tao, WANG Yu 2010, 10(6): 150-155 .  Abstract ( )   PDF (1104KB) ( )   In order to analyze the influencing factors of waiting time for inspecting, train technique process time and train inspection stuff utilization ratio in different conditions of train arrival imbalance, marshalling numbers and train inspection work organization, the time index representation method of train access, brake testing and technical inspection are presented based on marshalling numbers, the quantitative models of various time indexes of train inspection are setup by principles of statistics, and a microscopic simulation model of Train inspection operation is proposed for railway marshalling station based on Arena simulation software. Simulation result shows that the main influencing factors of waiting time for inspecting and train inspection stuff utilization ratio are the imbalance of train arrival and work organization of train inspection, the work organization also has significant influence on the time of train technique process, marshalling numbers has no significant influence on waiting time for inspecting, train technique process time and train inspection stuff utilization ratio. References | Related Articles | Metrics

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Travel Behavior Analysis Model of Suburban Railway Based on Combination of RP and SP Data ZHAO Dan,SHAO Chun-fu, SUN Zhuang-zhi, LIU Jian-feng 2010, 10(6): 156-162 .  Abstract ( )   PDF (1331KB) ( )   Under the impetus of the expansion of city size as well as the reform of railway transportation, suburban railway system has gradually merged into urban public transport system aiming at being the main means of long-distance transportation between center city and satellite town for commuters, which will be of great benefit to ensure the implement of city spatial development strategy and avoid the “over pie” pattern. According to the RP and SP data obtained from the residents trip survey along the suburban railway, travel behavior analysis is conducted, and three models which are respectively based on RP data, SP data and RP-SP combined data are built; by the contrast of three models’ calculation results, it can be seen that RP/SP combined model not only takes advantage of the reliability of RP data but also corrects the bias of SP data, so it performs much more accurately and effectively. The paper also comes to another conclusion that fare reduction will lead to higher contribution rate of suburban railway. References | Related Articles | Metrics

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Highway Network Distribution Equilibrium Based on Gini Coefficient HE Yi-hao,FAN Bing-quan,DONG Jie-shuang,LIANG Chao 2010, 10(6): 163-168 .  Abstract ( )   PDF (848KB) ( )   The paper establishes an evaluation index system considering highway network area density and transport density. The evaluation model for equilibrium distribution is also developed with integration of the Gini coefficient theory and the highway network distribution evaluation. A case study is conducted based on the Wenzhou highway network. The results show that the distribution of Wenzhou highway network is developed from absolute balance of low level to less balance of higher level, the network is relatively rational now, but the distribution of high-grade highway is significant imbalance. The coordination of highway network and the regional transportation intensity distribution has been markedly increased. At present, highway passenger transportation density distribution is in a relatively balanced state; highway freight transportation density distribution is in absolute balance. The results are consistent with characteristics of Wenzhou highway network development. References | Related Articles | Metrics

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Traffic Complex Network Node Importance Assessment Based on FCM Clustering WANG Li,YU Xin-yu,LI Ying-hong, LI Zheng-xi 2010, 10(6): 169-173 .  Abstract ( )   PDF (645KB) ( )   It is very important to select hub junction in urban traffic complex network for regional traffic signal control. Generally, SCOOT/SCATS systems select traffic flow and distance between junctions as reference which means engineers’ experience should play importance roles in practice. In this paper, node degree, node betweenness and high peak hour traffic flow are selected as indexes for traffic network node importance assessment process. And FCM clustering method is applied to analyze which one junction could be act as a hub node for regional traffic control. Moreover, a regional urban network including almost fifty nodes around Chang’an Street in Beijing of China is used as trail area to test upper approach. Data result shows Changchunjie, FuyoujieNankou and Hepingmen junction have high clustering characteristics when clustering number are 3, 4 and 5. And the clustering center shows very similar prosperities with real hub node in practice. In conclusion, FCM clustering analysis could provide theoretical support for traffic weighted complex network hub node selection. References | Related Articles | Metrics

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Research of Miles-In-Trail Strategy in Sector Boundary Based on Genetic Algorithm SUN Hao, HU Ming-hua, ZHANG Ying 2010, 10(6): 174-179 .  Abstract ( )   PDF (751KB) ( )   For the lack of M.I.T currently implements in China, which is entirely generated according to controllers’ experience, this paper, on the basis of the existing forecasting and flow management and the custom of controllers, proposes a method of Miles-In-Trail strategy in sector boundary based on genetic algorithm. In order to obtain the maximum flow in the control period on condition of the matching between flow and storage capacity, this paper establishes the integer programming model of M.I.T strategy in sector boundary and algorithm based on genetic algorithm, meanwhile, puts forward the concepts of sector acceptance ability in sector, and then verify the practicability of the model by using the specific example. The results show that this method is practicable, because it can make full use of the storage capacities of the sector to the maximum extent,and can be according to the custom of controllers, avoiding the probability of saturation of the sector. References | Related Articles | Metrics

Cases Analysis

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Urban Regional Traffic Level of Service Evaluation Based on Fuzzy Integral ZHANG Ye, JIA Li-min, CAI Guo-qiang 2010, 10(6): 180-184 .  Abstract ( )   PDF (605KB) ( )   At present, with the stabilization of the big cities’ road network buildings, urban traffic level of service becomes the most important evidence for the traffic managements make decision. Thus, the regional traffic level of service (LOS) evaluation becomes a sticking point in urban traffic research to improve urban traffic management. This paper proposes a regional traffic LOS evaluation model based on the fuzzy integral. It can solve non-additivity of regional traffic LOS by synthesizing indexes value of several segments, in other words, the regional traffic LOS is neither the result of single parameter measure, nor the result of local traffic parameters’ simple sum. In this paper, we uses fuzzy integral to meso-layer regional LOS assessment results from microcosmic layer attributes by real data. It can get rid of the subjective constraints, numerical examples applied in Beijing typical regions, the computational results show that the methods in region traffic can estimate the LOS of region traffic effectively. References | Related Articles | Metrics

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Study on Traffic Organization for Large Special Events in Beijing GAO Feng-chang, LI Jin, WANG Jiang-yan, HUANG Di 2010, 10(6): 185-189 .  Abstract ( )   PDF (1225KB) ( )   In Beijing, over 100 large special events were held every year. How to keep the traffic smoothly and reduce the impact on daily traffic during the event time is a key point of a successful large event. It’s also an important problem to the traffic organizer and manager. This article defines large special events from traffic aspect, analysis the characteristics and difficulties of traffic organization, provides traffic planning guidelines for large special events, and then takes the 7th China Flower Expo in Shunyi as an example, discusses traffic planning and implementation for large special events. Hope this article may provide helpful experience for large special events traffic planning. References | Related Articles | Metrics

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Clustering Adaptive Weighted Fusion Algorithm of Wireless Sensor Network for Railway Embankment Monitor SHEN Hai-yan, FENG Yun-mei 2010, 10(6): 190-194 .  Abstract ( )   PDF (593KB) ( )   Due to energy and bandwidth constraints，data collection，processing and transmission of wireless sensor network deployed in railway roadbed monitoring area，are required to be low energy consumption, high efficiency and high reliability. This paper puts forward the wireless sensor network clumping deployment strategy for intelligent monitoring, which would deploy data collection node as much as possible, and divide network to cluster as a single unit according to the number of node types, environmental characteristic. Processed the collection data using adaptive weighted fusion processing technology, which helps reduce data redundancy, improve data accuracy and collection efficiency. Simulation performance analysis shows that this method can greatly improve the data transmission efficiency, reduce the network energy consumption and prolong the network life cycle. References | Related Articles | Metrics