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25 April 2012, Volume 12 Issue 2 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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Hub Airport and Regional Economic Development Impacts of Airport on Regional Economic Development ZHANG Guo-Wu 2012, 12(2): 1-8.  Abstract ( )   PDF (474KB) ( )   As one of the essential part of the integrated transportation network, airports in China have witnessed great achievements since 1949. They have also exerted significant impacts on China’s urban economic growth, industrial agglomeration, employment and transport structure. The theme of the 26th conference of “Traffic and Transportation Forum 7+1” is “hub airport and regional economic development: impacts of airport on regional economic development”. It focuses on evaluating the impacts of hub airport on economic development and fully utilizing its pushing effects. The Beijing International Capital Airport (BCIA) is mainly analyzed to reveal the interactive development of airport and economic development. Some relevant evaluating indexes are put forward, the direct, indirect impacts, and the attracting impacts are computed for economic development. The development of airport economy and industrial garden area are also discussed at the conference. Related Articles | Metrics

Forum about Comprehensive Transportation System

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Analysis on Cost of Urban Rail Transit LI Wen-Xing, YIN Shuai 2012, 12(2): 9-14.  Abstract ( )   PDF (394KB) ( )   Nowadays，urban rail transit has been the most effective solution to traffic congestion because of its fast，efficient，safe，energy saving and environmental protecting characteristics. However，the high cost of rail projects and the operation maintenance，together with the social problems brought by the urban rail transit such as noise pollution，traffic accidents and air pollution have become the “bottleneck” of its healthy development. This paper systematically analyzes the internal and the external costs of Beijing Subway Line 4 as an example. Based on the value chain theory，the internal cost is divided into preliminary planning and designing cost，constructing cost and operating cost. On the other hand，the external cost is classified into the cost of air pollution，traffic accident and noise pollution. The external cost is quantified，incorporated into the total cost of rail transportation as well. This research provides the basis for the government to formulate the fare by accurate calculation of the total cost of urban rail transit. Moreover，this research promotes the sustainable development of economic resources，social resources and environmental resources. References | Related Articles | Metrics

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Decision Method for Logistics Business Mode of Manufacturing Enterprises FU Peng-Bo, LV Yong-Bo , REN Yuan, CHEN Li 2012, 12(2): 15-20.  Abstract ( )   PDF (435KB) ( )   Manufacturing logistics is in transition from traditional distribution to integrated logistics. According to the enterprise’s status and combination of factors, it is essential to make correct decision of the logistics business model. This paper develops logistics business mode by scenario for manufacturing enterprises. It selects the logistics needs of the community, the level of thirdparty logistics and logistics foundation as threetier idea of variable. Totally 27 feasible option sets are formed and divided into thirdparty logistics, logistics mix, selflogistics and industrial logistics. The decision tree method is proposed to solve the multistage decision of single enterprise, with steel manufacturing enterprises for example. The profit and loss value matrix of risk decisionmaking are applied to calculate the expected value of the idea of program, and the comparison shows mixed logistic model is more suitable for China’s steel enterprises. References | Related Articles | Metrics

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The Effect of Urban Travel Cost on Travel Structure YANG Zhong-Wei, LIU Xiao-Ming 2012, 12(2): 21-26.  Abstract ( )   PDF (959KB) ( )   In nowadays, urban traffic congestion has become a key factor influencing the rapid social economic development, and how to reasonably distribute all kinds of resources asand balance supply and demand of urban transportation are the significantly important issues for urban sustainable development. Through summing up the contents and classifications of travel costs, this paper analyzes the impacts of different types of travel costs on travel structure. Furthermore, an investigation, relating to the impact on car use for travel costs, is carried out; the results and conclusions are analyzed and evaluated as well. Finally, the paper points out that the economic measures, which can control the average travel costs of private cars, play important roles in controlling the use of private cars, improving the urban traffic structure, adjusting the traffic demands, and eventually alleviating urban traffic congestion. References | Related Articles | Metrics

Intelligent Transportation System and Information Technology

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Signal Control Strategies for Bottleneck Area on Urban Expressway YIN Sheng-Chao, XU Run-Min, ZHANG Yi, LI Zhi-Heng 2012, 12(2): 27-33.  Abstract ( )   PDF (1726KB) ( )   Urban expressways in China have special features. Distance between onramp and offramp is relatively shorter compared with this that in developed countries (normally longer than 1000 m), offramps are usually connected with urban streets and intersections. Thus successful ramp control strategies used in Europe or U.S. may not be suitable in China. First, this paper studies traffic flow characteristics at several representative “bottlenecks” in Beijing urban expressways. Efforts are devoted to improve the capability of traffic simulation platform to simulate detailed traffic behaviours by calibrating simulation model parameters. Efficiencies of different signal control strategies in road network involving onramp, offramp, adjacent streets and intersections are compared. Results indicate that combing adaptive ramp control with Synchronization signal control strategies is an efficient way to enhance road capacity and alleviate congestions for urban expressways. References | Related Articles | Metrics

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Dynamic Neural NetworkBased Integrated Learning Algorithm for Driver Behavior LIANG Jun, SHA Zhi-Qiang, CHEN Long 2012, 12(2): 34-40.  Abstract ( )   PDF (680KB) ( )   Vehicle driver’s perception, judgment, decision and action towards traffic environment are usually uncertain and inconsistent during their driving processes. Thus, it is difficult to use the traditional driving decision model to accurately predict the driving behaviors under these circumstances. This paper proposes a DNNIA algorithm to describe driving behavior by dynamically integrating ANNs. Specifically, some ANNs are first trained to learn different kinds of driving behaviors based on sample data and small amounts of these ANNs with minimal generalization error E are then selected and integrated to predict the final driving behavior. The Lagrangian function method is used to resolve the coefficientωi for optimal ensemble. Moreover, by introducing the idea of agent alliance, the study takes each individual ANN as an agent in the alliance and outputs the maximal value among all the weighted average outputs of the neuron in each individual ANN. The proposed method is evaluated on some benchmark datasets to show its effectiveness. In addition, the predicted driver’s habitual behavior by DNNIA, such as braking pedal, consistently accord with that revealed by the sample data, which proves its practicality for realworld problems. References | Related Articles | Metrics

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Measuring Variability of Arterial Road Traffic Condition Using Archived Probe Data LI Qiang, GE Qian, MIAO Li-Xin, QI Ming-Yao 2012, 12(2): 41-46.  Abstract ( )   PDF (4199KB) ( )   Because realtime traffic information is not available from current probe vehicle system, archived probe data become extremely important in studying timeofday variability of traffic condition. Timeofday variability of mean travel speed of a particular link is analyzed based on archived probe data from a field experiment conducted by the Nagoya PDRGS research association, Japan. The analysis shows that the mean travel time cannot reflect the variability of road traffic condition. For measuring variability, the mean speed and the amount of probe data should be used; in peak hours, mean speed reflects the variability of congestion and in offpeak hours, the amount of probe data can reflect the variability of traffic condition. References | Related Articles | Metrics

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3D Simulation of Adaptive Cruise Control Based on OGRE SU Yong-Sheng, ZHAO Dong-Bin 2012, 12(2): 47-52.  Abstract ( )   PDF (1302KB) ( )   Adaptive cruise control is an advanced driver assistance system, which assists driving on highway and urban roads within the entire speed range. The current method to test the results of vehicle adaptive cruise control algorithms are mainly upon the control curves. It is not intuitional. This paper develops a realistic driving simulation system based on the OGRE graphic engine. It could simulate any driving scenarios and visually test the control effect of the adaptive cruise control algorithms. Then, a PD optimal control algorithm is designed to realize the adaptive cruise control and verified on this 3D simulation platform. Experiments show that the 3D simulation of adaptive curise control can be used for any driving scenarios simulation. It can also effectively test the effect of vehicle adaptive cruise control algorithms. References | Related Articles | Metrics

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Simulation on Route Guidance Benefit of InVehicle Navigation System YANG Zhen-Zhen, GAN Hong-Cheng 2012, 12(2): 53-61.  Abstract ( )   PDF (494KB) ( )   Invehicle navigation system (IVNS) usually provides realtime traffic information to assist drivers to choose optimal routes. To explore the route guidance effect of IVNS’s market penetration rate to freeway networks, including traffic benefit and environment benefit, this paper uses macroscopic dynamic traffic network model to develop a simulation platform. It uses dynamic traffic assignment model to describe route guidance mechanism of the IVNS and adopts total waiting time and total time spend as traffic benefit indicator. The VTMicro model is used to measure vehicle emissions and fuel consumption. Moreover, the study calculates the direct economic benefits in terms of air pollutant treatment cost saving and fuel consumption. Taking a network with two origins and two destinations as an example, the simulation shows that the IVNS can effectively equilibrium freeway network’s demand, improve freeway network efficiency, reduce mobile source emissions and create huge economic benefits. Market penetration rate is recommended to value from 0.2 to 0.3 in view of traffic benefits and environment benefits. This simulation system is effective for designing and evaluating the IVNS. It also provides the basis for decisionmaking and references for relevant departments to improve the operational efficiency of traffic networks. References | Related Articles | Metrics

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Traffic Information Coverage Model of Probe Vehicle System Based on Link Characteristics Variables RAO Zong-Hao, YAO En-Jian 2012, 12(2): 62-66.  Abstract ( )   PDF (358KB) ( )   As a new method of traffic information collection, the probe vehicle technology has been widely used. The current challenge is to determine the number of probe vehicles in the premise of certain coverage. This paper summarizes the researches on the domestic and international traffic information coverage models of probe vehicle, and analyzes the shortcomings of existing products. Considering the coverage mechanism and effects of link characteristics, a coverage model including link characteristics is proposed. For model solution, the maximum likelihood estimation is adopted to obtain the parameters. Finally, an example is presented using the field data from probe vehicle system of Nanjing city of China. The result proves the feasibility and effectiveness of the proposed model, and this method could provide reference to the probe vehicle data collection scheme in the cities. References | Related Articles | Metrics

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Two Vehicle Dynamics of the CarFollowing Models on Realistic Driving Condition GUNAWAN Fergyanto E 2012, 12(2): 67-75.  Abstract ( )   PDF (518KB) ( )   The paper discusses the traffic dynamics in microscopic level and analyzes the dynamics characteristics of the traditional GazisHermanRothery model, the optimal velocity model with delay, and the intelligent driver model. An essential feature differentiating those models is that the traditional GazisHermanRothery model only governs the vehicle dynamics in the carfollowing state, but the other two models encompass larger interaction state including the freeflow state and the acceleration from the vehicle initial state. From this study, it can be concluded: (i) the optimal velocity model and intelligent driver model are more complete than the traditional model; (ii) the existing optimal velocity model may produce an unrealistic vehicle interaction; (iii) the optimal velocity model with a realistic delay can produce a stable interaction, and (iv) the intelligent driver model still needs further development particularly to take into account the driver delay which is an important aspect in the traffic dynamics on the microscopic level, and finally, (v) those three models may produce similar dynamics characteristics. References | Related Articles | Metrics

Systems Engineering Theory and Methods

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Stochastic Traffic Equilibrium Based on Travel Time Robust Reliability SUN Hua, GAO Zi-You 2012, 12(2): 76-84.  Abstract ( )   PDF (546KB) ( )   An assumption that pervades the current reliablitybased traffic equilibrium problem is that probability distributions of the origindestination (O-D) demand or/and link capacities are known explicitly. However, these distributions are difficult to be accurately obtained. This paper relaxes this assumption. It only needs to know the first m moments of travel demand (where m is a positive integer associated with the formulation of link cost function ) ,and then applies two worstcase ValueatRisk (WVaR) and worstcase Conditional valueatrisk (CVaR) risk measures to define robust percentile travel time (RPTT) and robust meanexcess travel time (RMETT) and prove that this two kinds travel time is equal under general distribution. Based on the defined travel time, the robust percentile stochastic user equilibrium (RPSUE) or robust meanexcess stochastic traffic equilibrium model (RMESTE) is proposed by incorporating trarelers’percoption error, which is formulated as an equivalent routebased variational inequality. Conditions are established guaranteeing existence of this equilibrium. A heuristic solution problem is introduced to solve the variational inequalities problem. A numerical example is used to illustrate the applications of the proposed model and the solution algorithm. References | Related Articles | Metrics

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Derivation, Implementation and Examination of Logit Route Choice Model with Relative Impedance LAI Xin-Jun, YU Zhi, LI Jun 2012, 12(2): 85-90.  Abstract ( )   PDF (380KB) ( )   In the paper, the modified Logit route choice models with relative impedance are presented to resolve the fixed variances problem of the traditional logit model. Therefore, the variances of perception error are relative to the route impedances. The classical variations of Logit models employing relative impedances are deduced. Three numerical tests show that the proposed models are more reasonable and robust than the traditional ones, and the modified PCL model with Probit equivalent impedances is the closest to theoretical results. The revised models have clear theoretical background, perform more rationally than traditional ones and still retain the advantage of easy computation, which makes them flexible in research and practical application. References | Related Articles | Metrics

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PsychologicalPhysical Force Model for Bicycle Dynamics LIANG Xiao, MAO Bao-Hua, XU Qi 2012, 12(2): 91-97.  Abstract ( )   PDF (713KB) ( )   The core challenge in modeling bicyclist behavior dynamics is how to tackle the interaction between the lateral and the longitudinal movements. Further the bicycle transportation could be considered as multiparticle selfdriven system. The combined dynamic model, psychologicalphysical force model (PPFM) and trajectories choice model (TCM), is proposed as a multi agent model to describe bicycle microscopic behavior dynamics. The PPFM is a continuous force model, which obeyed to the Newton’s second law. By introducing the trajectories choice behavior in the tactical level, the TCM is modeled to describe the ability to individual autonomous thinking and to respond to changes ambient conditions for predefined behavior tank. Through designing computational experiments, the simulation data is collected to calibrate and validate the models. The simulation results show that the fundamental diagram obtained by simulation is dovetail into the empirical data. The PPFM is capable of describing the nonlinear interaction between individuals and the microscopic behavior of the proposed bicycle dynamic model with reasonable traffic. References | Related Articles | Metrics

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Simulation of Manufacture Inventory Strategy Based on Through Train Supplies HE Guo-Xian, FU Zhong-Ning 2012, 12(2): 98-104.  Abstract ( )   PDF (1112KB) ( )   This paper focus on inventory strategy of manufactures on the basis of bulk raw material supply provided by railway through trains. The outbound quantity of materials is rely on the stochastic output, such as the probability distribution of daily sales volume of certain products, production breakeven point and the designed capacity of progressive assembly line. The inbound quantity is determined by the railway train diagram and landed weight in accordance with orders. The time step method is used to obtain optimum solution by computer simulation. The model is composed by inventory holding costs, ordering costs based on order discount, procurement constant expense and material shortage costs. One example with given demand probability distribution and certain railway cargo transportation timetable is simulated by MATLAB program. The study reveals that computer simulation is more adequate for massproduction scale manufactures to make inventory management decisions. The result illustrates that order quantity and departure timeinterval of through train play more important role in inventory simulation system. References | Related Articles | Metrics

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Optimized Utilization of Arrival and Departure Tracks in Dedicated Passenger Lines WANG Bao-Shan, HOU Li-Xin, LIU Hai-Dong 2012, 12(2): 105-110.  Abstract ( )   PDF (665KB) ( )   The topological structure determines the functions of the station arrival and departure tracks. According to the requirement of receiving and departure operation at station, trackuse classification can effectively reduce the interference and improve the efficiency of the station. Considering the station topology and its operation programming, the paper formulates the optimization model for of arrival and departure track utilization. The three targets of the model are: meeting the arrivaldeparture service rules, enhancing the convenience of passenger’s riding, and ensuring the balanced utilization of technical equipments. The model is solved by the genetic algorithm (GA). The concept of induce variation is proposed for avoiding illness individual and ensuring the health of whole populations in the algorithm. Finally, the reasonableness of the proposed model and algorithm are proved by a case study. The result shows that the model and the algorithms have good efficiency, could work out more optimum solution, and meet the operation requirements of dedicated passenger station. References | Related Articles | Metrics

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Dynamic Empty Container Allocation Model and Algorithm Based on Technique Station Transfer Operation DUAN Gang, LI Yin-Zhen, TIAN Li-Na, HE Rui-Chun, CHEN Zhi-Zhong, CHEN Xiao-Lei 2012, 12(2): 111-118.  Abstract ( )   PDF (441KB) ( )   For a container terminal, empty containers are usually allocated from supply station to demand station by transfer in technique station, which brings large time and cost consumption. A multistage dynamic model in planning horizon is developed to reduce the empty container allocation cost. The objective minimizes total costs from vehicle rent in empty container transportation, transfer operation cost in technique station and the inventory cost or delay loss cost. To satisfy the empty container demand and supply capacity, the paper designs a hybrid genetic simulated annealing algorithm considering the impacts of transfer operation time and transportation time on time window of the station with empty container demand, and the station operation capacity limit as well. The numerical example shows that the model and algorithm can effectively optimize the empty container dynamic allocation. References | Related Articles | Metrics

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Congestion Analysisof Complex Traffic Network Based on Heterogeneity WANG Ling, WANG Jian 2012, 12(2): 119-125.  Abstract ( )   PDF (711KB) ( )   Network heterogeneity cannot be ignored for traffic congestion analysis, because it directly associates with network structure. This paper investigates the relationship between network heterogeneity index and network size, and analyzes the influence of heterogeneity index on traffic congestion. For this aim, the paper presents the definition of network heterogeneity index and establishes the traffic flow model of heterogeneous structure. The results show that the heterogeneity decreases with the network size. When network size is a fixed value and the heterogeneity index is at subcritical region, traffic congestion increases with heterogeneity index. Furthermore, it can also be found that when the heterogeneity index reaches the critical value, the average number of accumulated vehicles reaches its maximum and congestion is significantly serious. Therefore, those networks, in which heterogeneity index is smaller than or larger than the critical value, have more tolerant to congestion. Adjusting the heterogeneity index can improve the congestion of traffic network to some extent. References | Related Articles | Metrics

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Commuter’s Choice Behaviorof Travel Time and Travel Mode ZHUGe Cheng-Xiang, SHAO Chun-Fu, LI Xia, MENG Meng 2012, 12(2): 126-131.  Abstract ( )   PDF (414KB) ( )   With analysis of the joint choice features of travel time and travel mode, the paper develops two nested Logit (NL) models on commuters’ travel time and travel model choice behavior .The data from the 2005 Beijing household travel survey are used to estimate the two models by the BIOGEME. The structure of the NL model is identified by the inclusive value parameter, and the result reveals the travel timetravel mode model is more reasonable than the travel modetravel time model, which indicates that the commuters always choose the travel time at first and then consider the travel mode under the time constrain. Moreover, the parameters of travel timetravel mode model are calibrated and analyzed. The joint choice features of travel time and travel mode are further discussed, which provides theory basis for relevant management policy making during peak time. References | Related Articles | Metrics

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Random Elasticity Analysis on Urban Travel Mode Choice ZHANG Rui, YANG Jing, LEI Xi-Wen 2012, 12(2): 132-136.  Abstract ( )   PDF (680KB) ( )   Among the factors that impact on urban travel mode choice, the ones with random distribution is the main focus of this paper.The aggregate strategy traffic model (STM) is used for model choice analysis. With the field data, the car’s travel speed is observed to be a random variable following the kstep Erlang distribution. Based on the random elasticity concept in economic theory, the elasticity calculation model of car travel speed on the travel mode choice is developed. The model is validated by the field data of Beijing city. The results indicate that the higher the reliability of transport policy indicator (influencing factor) is, the random elasticity becomes more steady and concentrated, and the policy target is more reliable to be realized. References | Related Articles | Metrics

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Intercity Transport Mode Spilt Calculation Method Based on Rank Logit Model WANG Xiao-Zhi, ZHAO Sheng-Chuan, YAN Zhen-Zhen 2012, 12(2): 137-143.  Abstract ( )   PDF (836KB) ( )   Intercity transportation plays an important role in urban economic growth, which is also an important research field of transportation planning. With the rapid development of highspeed railway, intercity transportation mode split is correspondingly changing in China. The Rank Logit model is one of the methods to measure the mode spilt in transportation research. The method can make full use of ranking data from SP survey to improve the model accuracy. The paper investigates the GuangzhouWuhan corridor and collects 891 SP survey data from the corridor to formulate a Rank Logit model. The analysis of the model indicates that the RL model has higher accuracy and more reliability from three perspectives as evaluation index, parameter rationality and value of passenger time. Finally, the paper carries out political sensitive analysis with six group examinations. The proposed method can be used to assit traffic planning and policymaking or provide reference for implementing and adjusting operation strategy. References | Related Articles | Metrics

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Travel Time Reliability Evaluation Model for Adjacent Bus Roads SONG Xiao-Mei, YU Lei 2012, 12(2): 144-149.  Abstract ( )   PDF (2273KB) ( )   Travel time reliability evaluation of adjacent bus roads contributes to making deep analysis on operational state of bus roads, finding weak roads and improving bus service level. The paper analyzes the distribution of adjacent bus roads travel time per mile. The Normal, Lognormal, Gamma and Weibull distributions are used to fit with bus roads based on sufficient field data. The lognormal is proved to be the fittest distribution. The paper also measures the threshold of bus roads travel time per mile under different service levels by percentile method. At the last section, the paper proposes a model for travel time reliability evaluation of adjacent bus roads based on service levels. The proposed method is evaluated by the operational data of bus line No. 337. References | Related Articles | Metrics

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On ramp Metering Algorithm Based on Realtime Density GAO Wan-Bao, WU Jian, ZOU Jiao 2012, 12(2): 150-155.  Abstract ( )   PDF (422KB) ( )   With the continual increase of urban traffic demand, traffic congestion occurs more and more frequently.Ramp metering, by regulating the vehicles entering freeway, has been proved to be an effective measure of relieving freeway congestion.This paper presents an optimal ramp metering algorithm with full consideration of the dynamic freeway and ramp density.The algorithm aims to maintain freeway density near the critical value and minimize the ramp queues.The PARAMICS is used to evaluate its performance comparing with the ALINEA and DemandCapacity algorithms.The data of freeway density, ramp queues, total vehicle travel time and downstream flow are also collected for each simulation.Analysis result shows that the Densitybased algorithm is effective in maximizing mainline traffic flow, optimizing the balance of network traffic condition and reducing ramp queues. References | Related Articles | Metrics

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Differential Evolution Bacteria Foraging Optimization Algorithm for Bus Scheduling Problem LIU Qin 2012, 12(2): 156-161.  Abstract ( )   PDF (390KB) ( )   To improve the effectiveness of the bus scheduling scheme, a model is developed by considering the average daily passenger volume of bus and the maximum and minimum departure intervals. The objective function of the model is to minimize the company’s operating costs and passenger’s waiting time. The bus scheduling is a typical NPhard problem. A differential evolution bacteria foraging optimization algorithm is then presented to solve the NPhard problem. As the velocity of the traditional bacteria foraging optimization algorithm is slow, the bacterium position is improved by differential evolution in chemotaxis process to improve the convergence precision. Based on the real traffic data of several bus lines, the model is calculated and simulated through programming. The simulation result shows that the model and the optimization algorithm can obtain the satisfaction solution more effectively. References | Related Articles | Metrics

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Urban Traffic Organization with Road Blocking Activities SONG Li-Ying, ZHANG Wen-Yi 2012, 12(2): 162-167.  Abstract ( )   PDF (873KB) ( )   The negative impacts of road constructions on local traffic have been acknowledged widely, which could be improved by appropriate scheduling. Therefore, this paper proposes an integrated approach embedded with microscopic traffic simulation technology to guarantee the optimal schedule for the road blocking activities. To improve the optimizing capability and enhance the computing efficiency, a revised genetic algorithm is introduced. A numerical example is then presented to verify the performance of current algorithm and its revised versions. The simulation results indicate that the proposed method is efficient in terms of optimal solution. References | Related Articles | Metrics

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Modeling Passengers’ Orderly and DisorderlyBoarding Behavior in a Transit System DING Jian-Xun, YANG Qian, HUANG Hai-Jun 2012, 12(2): 168-173.  Abstract ( )   PDF (929KB) ( )   Cluster and other complex phenomena of bus flow easily occur due to such factors as bus stop location, passenger distribution and boarding behavior in a transit system. A new cellular automaton model which simultaneously considers these factors, particularly the passengers’ orderly and disorderly boarding behavior, is proposed in this paper. Numerical simulation results, which match the analytic results well, show that the model can explicitly depict the spacetime trajectories of bus movement along a bus line, reproduce the cluster and jam phenomena of bus flow, and quantitatively evaluate the impacts of various factors on bus average speed. The study provides insights on formation mechanism of cluster phenomena under different boarding modes, advocates orderly boarding behavior and helps the optimization of locating bus stations. References | Related Articles | Metrics

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Reflective Crack Propagation and Fatigue Life of SemiRigid Base Asphalt Pavement WANG Hong-Chang 2012, 12(2): 174-180.  Abstract ( )   PDF (551KB) ( )   For the severity of semirigid base asphalt pavement reflective crack, a finite element analysis model of 20node isoparametric elements is established by the FEM software ABAQUS and fracture mechanics theory. The reflective crack of pavement is numerically analyzed and the crack fatigue propagation life is evaluated by the Paris formula. In the course of reflective crack propagation, the change of the stress intensity factor (K2 ) is discussed and the effect of pavement parameters on reflective crack fatigue propagation life is studied. The results indicate: (1) the propagation of reflective crack is dominated by deflection load. In the course of crack propagation, K2 keeps increasing till to damage. (2) The reflective crack fatigue propagation life increases with the raises of the surface course thickness, the base modulus, the subbase thickness and modulus and the subgrade modulus. It decreases with the increase of the surface modulus and the base thickness. References | Related Articles | Metrics

Cases Analysis

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Traffic Demand Characteristics of the 16th Asian Games and Its Strategy GAN Yong-Hua, LIN Sheng-Kang 2012, 12(2): 181-186.  Abstract ( )   PDF (1448KB) ( )   During the history of Asian Games, the 16th Asian Games is the one which has the largest number of competition events,joining people and competition venues. Traffic demand leaded by the Games will be highly gusty,mass and impactive. Under this condition,the daily traffic of the holding city has already been saturated,the games traffic and daily traffic will compete on the city’s transportation resource. In view of Guangzhou city’s daily traffic demand and operation situation,the paper systemically analyzes the traffic demand characteristics of Asian Games from aspects of passengers flow scale,service object,request standard and spacetime distribution. It also applies two traffic organization strategies to ensure Asian Games traffic to be safe and smooth efficient and ordered:“centralize transportation resource to ensure Asian Games traffic quality of service and reduce transportation disturbance for harmonious Asian Games traffic”. It then provides helpful suggestions for city to ensure effective traffic operation in largescale events. References | Related Articles | Metrics

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Passenger Surveillance Information and Management System at UMT Transfer Station of Beijing SUN Yu-Xing, GUAN Wei, ZOU Ying, GE Yu, SUN Yue 2012, 12(2): 187-193.  Abstract ( )   PDF (1408KB) ( )   With the development of urban rail transit, the rail network has been gradually formed, and the number of transfer stations also gets increased. As an important node for the passenger transfer, the safe and orderly operation of the transfer station becomes increasingly important. Based on the advanced passenger information monitoring, the paper analyzes the operation, monitoring and relevant requirements of urban rail transit. It then proposes the passenger information monitoring and emergency management solutions, which integrates the functions of data transmission, statistical analysis, information dissemination and emergency management. The scheme is successfully applied in Xidan hub of Beijing. The results show its advantages on monitoring, predicting and handling passenger traffic congestion and other emergency incidents. References | Related Articles | Metrics

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Problems and Recommendations of Beijing Metro Asset Management LI Yong-Liang, WANG Yao 2012, 12(2): 194-197.  Abstract ( )   PDF (394KB) ( )   Urban rail transit is complex system engineering with numerous management processes which involve huge number of facility instruments.Each process requires normative management strategies, to reduce the erosion of assets and maximize the effectiveness of assets.At present, Beijing rail transit has no systematic and specialized measures on metro asset management.And the lack of welldefined function and management procedure of related owners brings great difficulties to the management.It also leads to the postponement of assets recorded and lack of fundamental data in transformation, renovation and retirement.On the basis of analyzing the management process and the main problems of urban rail transit, in the paper, the relevant counter measures and suggestions are put forward from the aspects of institutional protection, supervision mechanism, and dynamic asset management. References | Related Articles | Metrics