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Large Data and Intelligent Logistics ZHANG Guo-wu 2015, 15(1): 1-10.  Abstract ( )   PDF (1248KB) ( )   The large data involves a large amount of information, and the large data technology changes the thought and method for human to understand the world. The intelligent logistics is to make the logistics system has the ability such as thinking, perception, learning, reasoning and judging, and to solve some problems in logistics, using integrated, intelligent and mobility technology. The intelligent logistics contains many items basic activities such as intelligent transportation, automated storage, dynamic distribution, and acquisition, processing and treatment of intelligent information. It provides the maximum profit for the supplier, provides the best service for the consumer, and consumes the least natural resources and social resources, thereby forming the integration of management and control for intelligent logistics. The 37th conference of“Traffic and Transportation 7 + 1 Forum” sets its theme as“Large Data and Intelligent Logistics”. To the application problem for large data technology in intelligent logistics field, it puts emphasis on the system, theory and method of intelligent logistics under the background of large data. It promotes the healthy development of modern logistics industry in China. Related Articles | Metrics

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The Spatial Difference and Correlation Analysis of Highway Development and Economic Development in China YU Jiang-xia 2015, 15(1): 11-16.  Abstract ( )   PDF (1637KB) ( )   This paper calculates the Theil coefficient and Gini coefficient of the highway development and economic development, studies the spatial difference and correlation of highway and economic development. The calculations are that: The spatial difference of highway traffic infrastructural construction is significant. The difference of the spatial and temporal variation of highway construction has a tendency to increase in the long run. And the difference mostly comes from the regional differences of four economic regions； The difference of the spatial and temporal variation of economic development is little than the one’ s of highway. The difference main comes from the difference between four economic regions, and the influence degree is up to 70% . There are significant correlation between the difference of spatial and temporal variation of highway and the ones of economic development. References | Related Articles | Metrics

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Traffic Structure in Middle-and-long Corridor and Transportation Strategy of High-speed Railway ZHU Yu-ting，MAO Bao-hua，WANG Yong-liang，LIU Lu 2015, 15(1): 17-22.  Abstract ( )   PDF (1564KB) ( )   A generalized cost function of passenger is built with measurement indexes, including economy, speediness, convenience, comfort and security. Then a mode split model is proposed by using the disaggregate theories. In order to analyze the changes of the passenger traffic structure in middle-and-long passenger corridor, Wuhan-Guangzhou corridor is selected as an example. And the market shares of transportation modes are forecasted with different values of time. The results show that the market shares of ordinary railway are more than 45%, which means that ordinary railway is more suitable for passengers. Finally, operation strategy of high-speed railway is analyzed based on profit. Results show that, due to the competition between high-speed railway and ordinary railway, it is difficult to achieve the maximum profit for high-speed railway operator and railway department at the same time. The high-speed railway operator has the highest profit when the price and running speed of high- speed railway are 275 yuan and 325km/h respectively; and the highest profit of railway department can be obtained only when the price and running speed of high-speed railway change to 350 yuan and 300km/h respectively. References | Related Articles | Metrics

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Life Cycle Assessment (LCA) of China’s Railway Network Based on Growth Curve WANG Yu，SHUAI Bin，LI Ji-tao 2015, 15(1): 23-29.  Abstract ( )   PDF (1882KB) ( )   Life cycle assessmen（t LCA）of China’s railway network evolution（1949–2020）is to obtained the periodic change and development law on spatiotemporal evolution by using growth curve theory. According to the maximum membership degree principle of adjust goodness of fit, the evolution process of China’s railway network were gradually fused four life cycle. Four typical growth curve model are adopted to fit the curves with each life cycle, then get the evolution law that the life cycle of China’s railway network follow the laws of Logistic model and the calculation formula and parameter selection of each life cycle is introduced. The results show that China’s railway network evolution follow the characteristics of the continuous form of growth curve and grouped into four life cycle, sprout cycle(1949–1969)，development cycle(1970–1988)，adjustment cycle(1989–1998)and prosperous cycle(1999–2020 later), each cycle follow the growth law like generation, growth and maturation. At present, the evolution of the railway network is in the growth stage of the prosperous cycle, the end of the life cycle time is about 2023, the total length of China’s railway network will reach 125,370 km. The related departments should take appropriate development strategy in different stages according to the growth law of China’s railway network evolution, guide and promote the China’s railway network transition to the next life cycle smoothly. References | Related Articles | Metrics

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Safety Evaluation of China’s Maritime Transport Key Nodes LV Jing,WANG Shuang 2015, 15(1): 30-36.  Abstract ( )   PDF (1424KB) ( )   Safety evaluation of maritime transport key nodes is an important part of protecting China’s maritime transport passage. In order to play a scientific and comprehensive safety evaluation of the key nodes of China’s maritime transport, an index system is established, and the projection pursuit model and genetic algorithm are applied to evaluate the security of key nodes. Furthermore, the main security threats of the related straits are excavated. The evaluation results indicate that: the security situation of the Strait of Hormuz, Malacca, Peter and the Suez Canal is relatively poor, which have a very important impact on China’s maritime transportation of oil, container and other important materials; in addition, the Lombok Strait, the Sunda Strait and the Makassar Strait also have relatively low level of security, which are all in Indonesia. The evaluation results provide scientific basis for China to develop measures to protect the safety of maritime transport and make related management decisions, and have great significance to improve China’s maritime transport security and reliability. References | Related Articles | Metrics

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Empirical Study on Ships Investment Decisions Based on Fractal Option Theory LI Dian-sheng, ZHANG Sheng-ze 2015, 15(1): 37-42.  Abstract ( )   PDF (1389KB) ( )   As the most important means of production, the early investment decision analysis of ships is vital to shipping company. All along, the calculated of investment risk value of the ship is one problem plagued to people. The development of real options theory and B-S pricing model provide a solution, but the most important assumption of B-S pricing model is that asset price volatility in line with the normal distribution which has a large gap between realities. The fractal option pricing model is established, and the fractal distribution assumption is chose in lieu of the normal assumption in B-S pricing model. Then the BDI index is used as empirical analysis. The result shows that H index of BDI logarithm yield sequence is greater than 0.5. On this condition, the ship investment real option value based on traditional B-S pricing model is greater than the fractal options value. This proves that B-S pricing model overestimate the real risk value of ship investment. Finally investors are prone to have psychological of blind optimism and increasing investment risk. References | Related Articles | Metrics

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Assessing the Influence of Shipping Company Investment for Efficiency of Terminal LI Dan, LUANWei-xin, PIAN Feng 2015, 15(1): 43-48.  Abstract ( )   PDF (1863KB) ( )   With the way of port investment becomes diversified, people witness that shipping enterprises transform into integrated logistic enterprises. That makes the merge of port and shipping enterprises becomes a new trend in the shipping industry. Under this circumstance, the three-stage DEA model is adopted to estimate the efficiency of coastal container terminal from 2008 to 2012 in China. The terminal will be divided into two groups based on investment structure. The relationship between investment structure and operation efficiency of container terminals is which the analysis focuses on in the latter section. The research outcomes show that the efficiency of container terminals incorporated with shipping enterprises is commonly higher than that of container terminals without any shipping enterprises’investment. The difference of pure technical efficiency is tiny, but the difference of scale efficiency is enormous. Shipping enterprise’s investment make vessels dock at its own terminal, which enhances the utilization of facilities. That turns out that the investment of shipping enterprises can promote the development of terminal enterprises. References | Related Articles | Metrics

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A Correlation Analysis and Modeling for Battery SOC and Driving Mileage of Electric Vehicle BI Jun, ZHANG Jia-wei, ZHANG Dong，CHENG Yong 2015, 15(1): 49-54.  Abstract ( )   PDF (1544KB) ( )   In order to solve range anxiety problems of the electric-vehicle drivers, and provide an important basis for the prediction of driving mileage. This paper proposes a method based on data driving to explore the relationship between the electric car driving mileage and battery SOC(State of Charge). Firstly, original data are processed by deleting, interpolation and averaging methods. The correlation is analyzed between driving mileage and battery SOC, and the model is established. Recursive least-squares method is studied to identify the parameters. Moreover, all experiments are performed by using the practical data from pure electric logistics vehicles running in Beijing to verify the established model and parameters identification result. The experimental results confirm that the prediction method of driving mileage based on data driving is feasible, and the model between driving mileage and SOC is established with high accuracy. References | Related Articles | Metrics

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Variable Speed Limit Control at Freeway Merge Bottlenecks Based on Reinforcement Learning 0 DUAN Hui, LIU Pan, LI Zhi-bin, TANG Dou-nan 2015, 15(1): 55-61.  Abstract ( )   PDF (2057KB) ( )   To improve the efficiency of freeway merge bottleneck, this paper optimizes the bottleneck variable speed limit strategy. Considering the characteristics of reinforcement learning that it is modelingfree and intelligent learning, a QL-VSL control strategy that integrates the Q-learning (QL) algorithm in the VSL control is proposed for the first time. The goal of the strategy is to maximize the outflow vehicle, it is adaptive learning through traversing traffic flow states and taking different speed limits. The cell transmission model (CTM) calibrated with the real traffic data is used for the simulation. The effectiveness of the proposed QL-VSL control strategy is evaluated with no VSL control and the feedback VSL control in the simulation. The travel time reduction and traffic parameter changes show that the proposed QL-VSL control strategy outperforms in improving the traffic efficiency and traffic operations at freeway merge bottlenecks. References | Related Articles | Metrics

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Detection and Analysis of Traffic Flow Characteristic Parameters Based on Time-space Trajectory Tracking REN Jian-qiang, CHEN Yang-zhou, XIN Le, SHI Jian-jun 2015, 15(1): 62-68.  Abstract ( )   PDF (1991KB) ( )   Video Based detection of traffic flow has great significance in intelligent transportation systems. For the low angle cameras, a novel traffic flow multi-parameters detection method is proposed in this paper. Three virtual detecting lines and a local background modeling with adaptive learning rate are used to quickly extract vehicle feature points and eliminate the influence of activity shadow. Based on a trained Adaboost (Adaptive Boosting) classifier, the feature points are grouped to vehicles. Then the grouping errors are eliminated based on the motion-similarity of feature points in tracking process and the vehicle trajectories are extracted accurately. After that, the multi-lanes time-space diagrams are generated and the multi-parameters of traffic flow are detected automatically. Experimental results prove the efficiency of the method. In addition, the multi-lanes time-space diagrams can provide strong support for more traffic information acquisition and more in-depth analysis of traffic flow characteristics. References | Related Articles | Metrics

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Driver Behavior during Yellow Interval Based on Video Detection Technology LI Juan, ZHOU Jing,LIN Yuan,WANG Qing-hua 2015, 15(1): 69-74.  Abstract ( )   PDF (1635KB) ( )   Yellow interval policy is a hot topic in the field of traffic safety. Traffic parameters are collected automatically by videos detection technology, including the distance to stop-line, speed, acceleration and the passing status of the vehicles. With these data, the“Stop/Go”decision model and the result of“Yellow Interval Running”model are set up. Predictions of the two models with the observed errors are 2.5% and 5.3%. The test results show that the video detection technology and driver behavior models can be applied to signalized intersection control management, which may provide appropriate support for the development and implementation of traffic management measures. References | Related Articles | Metrics

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Intersection Delay Considering about Up-stream Signal WANG Jin, ZOU Zhi-yun, GE Huan, ZHOU Zhi-hao 2015, 15(1): 75-80.  Abstract ( )   PDF (1743KB) ( )   Intersection delay is an important evaluation index for traffic design and signal optimization. To overcome the demerit that the traditional delay calculation method considers about the isolated intersection, a new delay model is built by taking into the up- stream and down- stream intersections considerations. The model is based on the traffic-wave theory, and it synthesized analyzes the main influential parameters of upstream and down-stream intersections, such as phases, splits, movement volume, link length, offset, etc. A polygon formed by spatiotemporal coordinates of the queues rears is constructed by capturing the evolution of queue phase by phase, which area is used to calculate the stop delay of the object lane-group of downstream intersection. The intersection signal control delay can be counted by adding stop delay and acceleration-deceleration delay. Through a case study comparing with VISSIM and SYNCHRO software, it is found that the model is reliable for intersection delay. References | Related Articles | Metrics

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Taxi Route Choice Behavior Modeling Based on GPS Data YANG Yang,YAO En-jian，PAN Long，ZHAO Nan 2015, 15(1): 81-86.  Abstract ( )   PDF (1451KB) ( )   Taxi route choice behavior analysis is of great significance to study urban traffic flow’s spatiotemporal distribution and assignment. First, based on the GPS data collected from taxi dispatch system, RP data for taxi route choice behavior analysis are obtained by using trip-identification method, map matching and double-sweep algorithm. Second, by considering the comprehensive impacts of road network condition and traffic status on taxi drivers’route choice behavior, a PSL model based vehicle route choice model is developed. Finally, the results of case study show that taxi drivers incline to choose the route with less travel time, lower frequency of the left turns and right turns, and higher total ratio of arterial road and sub-arterial road. Meanwhile, the modeling approach of route choice behavior is of positive significance to improve the use value of GPS data. References | Related Articles | Metrics

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Cellular Automaton Model for Traffic Flow under Ice and Snowfall Conditions ZHAO Han-tao, NIE Cen, LI Jing-ru 2015, 15(1): 87-92.  Abstract ( )   PDF (1699KB) ( )   A single-lane and a two-lane urban microscopic traffic flow models are developed under ice and snowfall conditions based on cellular automata. Drivers prefer to reduce speed and keep larger vehicle spacing for safety on ice and snowfall road. According to this phenomenon, this paper considers the cellular size and introduces speed factor and spacing factor which are different under different ice snowfall conditions. By numerical simulation, the curve diagram is obtained between velocity, density and flow in both normal and snow weather, and it analyzes the effects of different snow conditions on the traffic flow. It is found that the fluctuation range and level of vehicle speed in moderate snow is the maximum. Fundamental diagrams show that the ice and snowfall conditions have great influence on the critical density, maximum flow and other parameters. Metastable hysteresis phenomenon is not obvious, and the maximum of changing-lane frequency does not exist under ice and snowfall conditions. References | Related Articles | Metrics

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The Running Speed Prediction Model of Interchange Ramp ZHANG Zhi-yong, HAO Xiao-yun, WUWen-bin,WANG Dong 2015, 15(1): 93-99.  Abstract ( )   PDF (2093KB) ( )   Ramp is an important part of interchange, the ramp design idea based on the running speed is a new design idea of the highway and interchange. This paper is mainly focused on the interchange ramp running speed of the vehicle. Through the analysis of the influence factors of the interchange ramp running speed, the orthogonal experiment program is formulated, and then continuous running speed data of the vehicle on the four interchanges in Beijing is collected, in total of 14 ramps with the vehicle-mounted high precision GPS devices. According to 10 of these ramps’data, based on the running speed characteristics of the vehicle on the interchange ramp, the ramp is divided into three sections: deceleration section, uniform section, acceleration section. At last, the prediction model of each section between the interchange ramp running speed and the influence factors is established, and then the prediction model is verified through comparing the remaining four ramps’measured data. The results show that the relative error values of the prediction model are less than 5%, the accuracy of the model is validated. References | Related Articles | Metrics

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Network Equilibrium Assignment Model Depended on Stochastic Reference Point ZHANG Xi, LIU Hai-xu, CHEN Ling-juan, YANG Da, PU Yun 2015, 15(1): 100-105.  Abstract ( )   PDF (1612KB) ( )   As a complement for describing travelers’boundedly rational route choice behavior by cumulative prospect theory, the stochastic reference point is explicitly considered. It is defined as a product of stochastic shortest travel time and acceptable coefficient. By assuming that travelers follow the rule of maximizing route cumulative prospect to choose the route, corresponding stochastic equilibrium condition and equivalent fixed point model are established. Then, a heuristic algorithm is given based on Probit loading and method of successive averages. The proposed model and algorithm are testified on a small network. Numerical results show that the traffic flow pattern depending on stochastic reference point can virtually represent travelers’boundedly rational behavior through average travel time and fluctuation. Due to the sensitivity analysis of parameters, the network equilibrium state from CPT remains unchanged with different travel time fluctuations, but varies when travelers adjust their travel time budgets. References | Related Articles | Metrics

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Characteristic Research of Urban Complex Traffic Network WEI Zhen-lin, GAN Yang-jie, ZHAO Peng 2015, 15(1): 106-111.  Abstract ( )   PDF (1683KB) ( )   According to the actual traffic network in Third- Ring Road of Beijing, the complex network model of urban road traffic network is built, urban rail transit network and urban complex traffic network which is formed by the superposition of the former two. Based on the complex network theory, the value and distribution of the network’degree, clustering coefficient, average shortest way length, betweenness and node tightness are computed by Matlab and analyzed． Then, this paper compares the statistical characteristic values of the two network models. The results indicate that they both have the characteristic of low clustering coefficients of random network model and scale- free network model. After the addition of urban rail transit network, network diameter and average path length are reduced, and the average degree, node tightness and clustering coefficient are increased to different extent. The accessibility of the whole network is improved and the capacity of network becomes larger. References | Related Articles | Metrics

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Spatial Econometric Analysis of Road Turnover under the Energy Conservation and Emissions Reduction YAO Bao-zhen,SHEN Fei, YAO Jin-bao,WANGWen-si,WANG Shuang 2015, 15(1): 112-117.  Abstract ( )   PDF (1448KB) ( )   The spatial econometric model of road turnover (freight and passenger) is studied under the background of energy saving and emission reduction in transportation industry. Firstly, Moran’s I index is presented to examine the spatial correlation of provincial road turnover in China. And then, The Local Indicators of Spatial Association of road turnover is used to select the regions with high spatial cluster effect. On this basis, the spatial lag model and spatial error model of road turnover are conducted to analyze the influences of provincial road turnover. A certain scenario is established to analyze the influence of the reduction of road turnover in regions with high spatial cluster effect to their adjacent areas, and the contributions to energy saving and emission reduction of the whole country. References | Related Articles | Metrics

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Analyzing and Computing Dynamic Accessibility with Constraints of Schedule GUO Jian-yuan, JIA Li-min, QIN Yong 2015, 15(1): 118-122.  Abstract ( )   PDF (1350KB) ( )   When time close to the running of last trains, the number of active routes in urban rail transit will become less and less. The network accessibility changing along with the time is called dynamic accessibility. The method about computing dynamic accessibility is studied, which fits to the planning of last trains and improves the service quantity to passengers who want to take very late or even last trains to their destinations. These definitions are given, such as latest accessible time, route accessibility and OD accessibility. Then, the main steps to compute network accessibility with last trains running is presented, and a recursive algorithm is used to compute the latest accessible time. At last, a flow of applying network accessibility is proposed to optimize the connection scheme of last trains. The example is given to demonstrate the feasibility of the method. References | Related Articles | Metrics

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A Forecasting Method of Controller’s Workload Based on Ridge Regression—BP Neural Network WEN Rui-ying，WANG Hong-yong 2015, 15(1): 123-129.  Abstract ( )   PDF (2076KB) ( )   It is becoming a new hot topic in the field of air traffic management that evaluating the controller’s workload by the traffic complexity factors. Based on the radar data of Xiamen air traffic control station, 10 typical complexity evaluation factors were calculated. The strong multi-co-linearity among various complexity factors is discovered through co- linearity diagnosis. Using the ridge trace plot of ridge regression, the complexity evaluation factors are selected, and the combined model of ridge regression and neural network are established to predict the controller’s workload. The forecasting results are verified by the pilot/controller voice communication data. It shows that the combination model of ridge regression and BP neural network has fast convergence speed and less training time. The combined forecasting model has high precision because four performance indexes such as mean square error, root mean square error, mean absolute error and mean absolute relative errors are relatively small. References | Related Articles | Metrics

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Research on Sortie Generation Rate of Multi-types Military Aircraft Based on Closed Queueing Network Model YANG Fu-qin，QI Er-shi，LIU Hong-wei，ZHU Ming-zhu 2015, 15(1): 130-136.  Abstract ( )   PDF (1533KB) ( )   The sortie generation rate of multi- types military aircraft is one of the important indicators to measure aircraft combat effectiveness of air force air-station. This paper researches the sortie generation rate of multi-types military aircraft further. According to the process description of the aircraft sortie generation cycle, and on the basis of the queueing network, a closed queueing network model of the sortie generation cycle with multiple server FCFS service centers and multiple constant unit rate servers is set up. The sortie generation rate model of multi-types military aircraft is calculated by the extended mean value analysis. In terms of the analytic calculation, the sortie generation rate curve is worked out and the relationship between the sortie generation rate and the quantity of aircraft is analyzed. Combining with the performance measures including the mean queue length, resource utilizations and so on, the bottleneck factors are identified in increasing the sortie generation rate. At last, the calculated results from the closed queueing network model are proved by Monte Carlo simulation. Therefore the closed queueing network model and algorithm of the sortie generation cycle can be applied into the practice, and be helpful for the research on the sortie generation rate of multi-types aircraft. References | Related Articles | Metrics

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Forecast of Logistics Demand Using LSSVM Combining GRA with KPCA GENG Li-yan 2015, 15(1): 137-142.  Abstract ( )   PDF (1350KB) ( )   To reduce the complex structure of least squares support vector machine (LSSVM) in logistics demand modeling and improve the forecasting accuracy of LSSVM for logistics demand further, based on the grey relational analysis (GRA) and the kernel principal component analysis (KPCA), a LSSVM forecasting method is proposed. First, GRA is used to choose the main influential factors of logistics demand. Then, the KPCA is applied to extract the nonlinear principal components, which can eliminate the correlation in the main influential factors. Finally, the extracted nonlinear principal components are selected as the input variables of LSSVM to construct the logistics demand forecasting model. And the parameters of LSSVM are adjusted by the improved particle swarm optimization (IPSO). Using this method, China’s logistics demand is analyzed. The results indicate that the proposed method effectively reduces the number of the input variables in LSSVM and simplifies the structure of the LSSVM. The forecasting accuracy of logistics demand is improved to some degree. References | Related Articles | Metrics

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Flight Delay Prediction Using Support Vector Machine Regression LUO Yun-qian，CHEN Zhi-jie，TANG Jin-hui,ZHU Yong-wen 2015, 15(1): 143-149.  Abstract ( )   PDF (2080KB) ( )   To solve the problem that the flight delay is difficult to predict, the support vector machine regression method is used to establish the flight arrival delay prediction model. First, the phase space reconstruction theory is used to calculate the flight arrival delay’s the delay time, embedded dimension and maximum Lyapunov exponent, and the chaotic characteristics of the flight arrival delay time sequence is found. The phase space of the flight arrival delay time sequence is reconstructed and combined with the departure delay of the upstream airport’s flight using the same aircraft to build the input variable vector of the prediction model. Second, for selecting the optimal model parameters, the particle swarm algorithm, differential evolution algorithm and genetic algorithm are compared, the experiment shows that differential evolution algorithm can get the optimal prediction model with a higher probability. Last, the prediction performance of the model, the single factor prediction model and the relevance vector machine prediction model are compared. The results show that the prediction performance of the model is much better than the other two, the model can effectively predict flight delays. References | Related Articles | Metrics

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Logistics Freight Volume Forecasting Based on Multilevel Decompose-ensemble Method ZHOU Cheng, LI Song 2015, 15(1): 150-158.  Abstract ( )   PDF (2013KB) ( )   Logistics freight volume forecasting is essential for forming logistics policy and determining the logistics infrastructure layout, which reflects strong- nonlinearity and ambiguity due to various affecting factors. A new forecasting approach based on multilevel decompose-ensemble is proposed for logistics freight volume. Original freight volume is firstly decomposed into trend component and non- trend component in accordance with trend decomposition. Then, non-trend component is further decomposed into a low frequency subseries and a several high frequency subseries by using of wavelet decomposition. With respect to their different features, trend component, low frequency non-trend component and high frequency non-trend component are respective forecasted. The prediction result of freight volume is the superimposition of these subseries predictions. Non-stationary time series is resolved into relatively stationary subsequences in accordance with trend decomposition and wavelet decomposition. The empirical test proves that the proposed forecasting method based on multilevel decompose-ensemble method is higher accuracy, which is compared with traditional decompose-ensemble forecasting method based on trend decomposition or wavelet decomposition. References | Related Articles | Metrics

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Model and Two-stage Algorithm on Dynamic Vehicle Routing Problem RAOWei-zhen，JIN Chun，LIU Feng，YANG Lei 2015, 15(1): 159-166.  Abstract ( )   PDF (1732KB) ( )   In order to effectively solve dynamic vehicle routing problem (DVRP), this paper analyzes the substantial effect of four main categories of dynamic information on classical vehicle routing problem, and transform DVRP into multiple static fleet size and mixed open vehicle routing problems (FSMOVRP). And FSMOVRP could be further converted to multiple capacitated vehicle routing problems (CVRP). The model based on CVRP is built up for DVRP. After that a two-stage algorithm is proposed to solve DVRP model according to the analysis of DVRP characteristics. In the first stage, a fast construction algorithm with merely O(nlogn) complexity is proposed on the basis of delivery region cutting strategy by K-d trees method. In the second stage, a hybrid local search algorithm is designed by analysis of structural principal of algorithm’s solution searching space. Finally for the purpose of algorithm verification, we design and solve 36 DVRP instances generated from 12 large scale CVRP benchmark instances. The results demonstrate the effectiveness of the model and two-stage solving algorithm. References | Related Articles | Metrics

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Research on Ideal and Conservative Time Flow for Emergency Evacuation on Road Network MAYi, YAN Yu-song 2015, 15(1): 167-172.  Abstract ( )   PDF (1397KB) ( )   Studying ideal evacuation time flow and conservative evacuation time flow for emergency evacuation problem is significant to predict the evacuation time in the situation of emergency. In view of this objective, a mathematical programming model for ideal and conservative time flow is built, meanwhile, two flow- augmenting algorithm to solve this model is developed by means of theory of the shortest path, the longest path and the minimum profit flow, the algorithm can not only calculate the flow assignment in ideal and worst evacuation situation, but also can calculate the corresponding value of evacuation time respectively, further, identify the range of total evacuation time. Finally a demonstration example is used to demonstrate the calculation process of ideal and conservative time flow, as well as discussing its evolution properties. References | Related Articles | Metrics

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Route Choice Model for Commuters Based on Cumulative Prospect Theory LI Xiao-jing, LIU Lin-zhong 2015, 15(1): 173-178.  Abstract ( )   PDF (1299KB) ( )   So as to describe travel behavior of decision makers under uncertain environment comprehensively and study route choice behavior and risk attitude of commuters from value variation and reliability variation, a route choice model for commuters based on cumulative prospect theory (CPT) is proposed. Firstly, CPT with two reference points is generalized. Then, travel time is budgeted according to uncertain theory, and on the basis of the budget travel time, a unified method for estimating commuters' reference point is presented. And then, a route choice model for commuters is established. At last, relationship between reliability and reference point and relationship between reliability and cumulative prospect value are studied on a test network. The results show that commuters' reference point can be set dynamically according to their requested reliabilities. When departure time is same, and when a traveler has a higher requested reliability, a lower risk path has a larger prospect value; whereas when a traveler has a lower requested reliability, a path with smaller mean travel time and although with a higher risk also has a larger prospect value. It is consistent with the fact. The proposed decision model can describe route choice behavior of commuters on random road networks effectively. References | Related Articles | Metrics

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A Markov-based Curbside Parking Model and Simulations TIAN Qiong, YANG Li, LUO Ting 2015, 15(1): 179-184.  Abstract ( )   PDF (1920KB) ( )   Referring to the classic circular city model, a curbside parking model based on the Markov chain theory is formulated. According to its Markov properties, the cruising competition queue is depicted through the viewpoints of the system and drivers, respectively. Consequently, the probability density function of the searching distance is derived, which proves that the traditional binomial distribution is limited in describing the competition behaviors between drivers. Then, a simulation algorithm is established to verify the theoretical results of the Markov model and find that besides the competition behavior, the continuouslyparking phenomenon is another major reason for difficult curbside parking. The finding extends our knowledge of curbside parking and can be helpful in designing the curbside parking policies. References | Related Articles | Metrics

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Modeling and Analysis of Pedestrian Choice between Stairway and Escalator in Urban Rail Transit Station SHI Rui-jia, DING Yong, BAI Yun, XU Qi, LI Ming-gao 2015, 15(1): 185-190.  Abstract ( )   PDF (1511KB) ( )   Based on the pedestrian behavior data of six transfer stations in the peak hour in Beijing, the importance degree of factors affecting pedestrian choice is calculated by gray correlation method. The probability of pedestrian choosing stairway is modeled and analyzed by fuzzy theory. The result shows that, the height of the stairway, queuing number before escalator and luggage are significant factors affecting pedestrians’choice. Fuzzy theory can effectively reflect pedestrian choice behavior in Beijing urban rail transit. Furthermore, when the queuing length before escalator is less than 25, the probability of choosing stairway is small and little affected by other factors. While the queuing length before escalator is more than 25, the probability of passengers choosing stairway increases significantly, and the smaller the load and height is, the impact by queuing length is more obvious. Passengers with different loads have the same regular pattern while stairway height changes and the probability of choosing stairway monotonically decrease while stairway height increases. References | Related Articles | Metrics

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Optimization for Waiting Passengers in Transfer Station Based on Train Connecting Coordination BAI Guang-zheng, GUO Jin, SHI Hong-guo, YANG Yang,WANG Xiu-xuan 2015, 15(1): 191-197.  Abstract ( )   PDF (1622KB) ( )   Optimization for the number of waiting passengers in transfer station by coordinating trains’ arriving time in the rush hour is studied. Firstly, it analyzes each factor which had influence on the passengers in each platform, and obtains formulas to describe the variation of waiting passengers with time in each direction. Secondly, it establishes the optimization model which minimizes the maximum of total waiting passengers during the study period. The model takes the site capacity as constraints, and takes trains’ arrival time in each direction in transfer station as adjustment object. Finally, the model is validated by an example, and genetic algorithm is designed to search the optimal solutions. It also obtains some worse solutions for contrast. By contrast, the optimal solutions can effectively reduce the number of waiting passengers in transfer station. The study can provide a reference for network coordination. References | Related Articles | Metrics

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Impact of Pedestrian on the Speed and Acceleration Profile Model to the Protected Left-turn Traffic CHEN Yi-xin, HE Yu-long, SUN Xiao-duan, XU Ting 2015, 15(1): 198-204.  Abstract ( )   PDF (1780KB) ( )   The vehicle flow under a protected left- turn phase is commonly affected by pedestrians. This paper investigates the average operating speed at the saturation flow rate with and without pedestrian traffic, and evaluates the effect of pedestrians, using the method of significant analysis. The influence factors contain the position (inside or outside of left-turn vehicle’s trajectory) and the number of pedestrian and the distance between the vehicle and pedestrians. The degree of pedestrian-vehicle impact is defined in four levels and the speed profile for the queuing vehicles in different impact levels is fitted by curve fitting software. The results show that saturation flow speed is mainly affected by the position of pedestrian (inside or outside of left-turn vehicle’s trajectory), and the distance, while the number of pedestrians is not an influence factor. The effect on the left- turn saturation flow by both sides of pedestrians is same to the effect by pedestrians on one serious side. The speed-time profile indicates an“S”shape from queuing vehicles start to reach the stable saturation flow, the vehicles need more time to reach the saturation flow when affected by the pedestrians, and the saturation speed is lower. However, the“S”shape of the speed- time profile is not affected. These findings may help lay a foundation for a better traffic management. References | Related Articles | Metrics

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Analysis of Air Traffic Flow Characteristics in Airport Terminal Area Based on Observed Data XU Yan, ZHANG Hong-hai, YANG Lei, LIAO Zhi-hua 2015, 15(1): 205-211.  Abstract ( )   PDF (2014KB) ( )   This paper studies the time-space characteristics of air traffic flow in airport terminal area, which aims at revealing the inner influence and congestion mechanism of air traffic flow and providing scientific basis for air traffic control strategies. First, the timing distribution of air traffic flow parameters for target air routes is established based on original radar data. Then, according to the fundamental diagrams and air traffic operations as well as control rules, the air traffic states are divided into three phases: free flow, weak intervention and strong intervention. Finally, on the basis of state division, the air traffic velocity- density model, flux- density model and flux- velocity model are proposed by linear regression analysis, and the significance of model fitting and parameters is tested by F and T test. The results demonstrate that the models are corresponding to air traffic flow characteristics and fitting for traffic states identification. References | Related Articles | Metrics

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Urban Road Network Junction Evaluation Method Based on the Functional Analysis WANG Jing-jing, YANG You-lin, LI Hui,WANG Dong-wei 2015, 15(1): 212-217.  Abstract ( )   PDF (1577KB) ( )   Whether the junction between different grades of roads is reasonable is directly related to the realization of the desired function of the road network. Based on the functional analysis, this paper puts forward the evaluation method of road network junction planning. At the stage of urban integrated transportation planning, the main goal is to provide the traffic function; while for the stage of urban road network special planning, it is to guarantee the service function. Using Monte Carlo simulation method, the system reliability of traffic function and service function are calculated, which are considered as the main evaluation indexes of road network junction schemes. The leapfrog cross-cutting problem is also discussed. Finally, a regional road network of Zhengzhou city is taken as an example for application, to testify the feasibility and rationality of the proposed method. References | Related Articles | Metrics

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Impact of Rainfalls on Travel Speed on Urban Roads GONG Da-peng, SONG Guo-hua, LI Ming, GAO Yong, YU Lei 2015, 15(1): 218-225.  Abstract ( )   PDF (2084KB) ( )   By utilizing Beijing real-time weather data, travel speed on urban roads and traffic performance index (TPI) based on floating car data (FCD), this paper analyzes and compares travel speed, TPI and rainfalls under rainfall weather and normal weather. Then, the operating parameters of urban roads are analyzed from the perspectives of precipitation intensity, time periods and congestion levels. Further, the correction model for speed prediction is developed and validated. The study shows that travel speeds on the expressway, major arterial and collector decrease by 8.8% , 4.0% and 5.9% respectively when the precipitation intensity reaches the moderate rain level or above at night, and further derives the relationships between the precipitation intensity and the travel speed reduction during the peak and non- peak hours. In addition, the relationships between the precipitation intensity and the travel speed reduction under different congestion levels are also obtained. Finally, application examples are presented to validate the proposed model, which shows that the model can effectively predict the travel speed under the rainfall weather, and the average prediction error is less than 5%. References | Related Articles | Metrics

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Analysis of Ninghang Intercity Travel Mode Choice Behavior Based on Panel Data WU Lin-lin，ZHANG Ming-yan，WANG Yang 2015, 15(1): 226-231.  Abstract ( )   PDF (1239KB) ( )   With the rapid development of Chinese urban agglomeration, new modes of intercity transport constantly emerge and the old ones are also continuously improved, which leads the intercity travelers to restructure their travel habits constantly. Thus, there is a need to build a dynamic model to study the intercity travel behavior of travelers and forecast travel demands. In this context, travel information before and after the opening of Ninghang Intercity Railway was investigated. The state dependence variable is introduced to express the effect of previous intercity travel mode choice decision on latter travel mode choice, the dynamic model of intercity travel mode choice is established based on panel data of two waves. The results indicate that the dynamic model performs better than the traditional models which only concern one wave travel data. According to the background of Ninghang intercity travel, three predicted policy scenarios are set to predict the mode spilt, the results show that the traditional model would overstate the degree of the change of mode spilt. The above conclusions can better serve for the Chinese intercity transportation planning. References | Related Articles | Metrics