فهرست مطالب

Transportation Engineering - Volume:6 Issue: 3, Winter 2019

International Journal of Transportation Engineering
Volume:6 Issue: 3, Winter 2019

  • تاریخ انتشار: 1397/04/13
  • تعداد عناوین: 6
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  • Maghsood Pouryari *, Nemat Hasani, Ahmadreza Mahboobi Ardakani, Kiarash Naser Asadi Pages 191-205
    In this research, the centers involved in relief operations in Tehran traffic area districts have been compared and the supply-demand ratio has been specified through a relation presented separately for each district. The supply has been evaluated based on three parameters: 1) No of relief centers, 2) congestion of the main road (the ratio of the length of the main road to the area of the district), and 3) the ratio of the length of the main road to those of the secondary roads. The demand has been considered based on the number of casualties waiting for relief per unit area of each district.
    After delimiting the districts in the case study and extracting the network’s populations and roads information layers in the GIS, two road classes were specified: 1) main roads (capable of working under disaster conditions) and 2) secondary roads (capable of obstructing relief operations in needy areas). Next, the parameters were co equalized with their corresponding maximum values and scaled in the 0-100 range. The final results have been shown separately for each district (totally 32 in number) as the accessibility index. Accordingly, districts with indices smaller than 2 are considered as weakly accessible and those with indices more than 15 as properly accessible; districts with indices 2-8.5 have average accessibility.
    Keywords: earthquake, accessibility, relief, Transportation, district
  • Shideh Ehteshamrad, Mahmood Saffarzadeh *, Amirreza Mamdoohi, Sorousha Saffarzadeh, Fernando Monterio Figueira Pages 207-216
    Negative consequences of car use along with deficiencies for investment in environmental friendly modes, have driven authorities to search for soft measure in order to encourage people for modal shift. The main objective of this study is to propose a model which describes car use behavior on parents’ work trips and how this relates to mode choice regarding their children’s school trips. A questionnaire survey was carried out in 24 randomly selected primary schools in Tehran, Iran (n=4000). A mean structural analysis based on the sample (returned questionnaires =1876) demonstrates that parents who accompany their children on school trips have a stronger intention to use car for work trips than parents who do not accompany their children on school trips. A structural equation model based on the theory of planned behavior suggests that using car on school trips along with car use behavior for work trips, significantly increases the car use behavior for work trips. Findings suggest that individuals as parents, and also parents who accompany their children on school trips need to be considered in planning and policy setting for modal shift providing soft measures sensitive to this issue, since parents are highly influenced by their parental roles involved with children’s requirements in school trips.
    Keywords: Car use behavior, mode choice, theory of planned behavior, commuting trips, escorting children to school
  • Ali Nadizadeh *, Hasan Hosseini Nasab Pages 217-235
    In this work, the capacitated location-routing problem with simultaneous pickup and delivery (CLRP-SPD) is considered. This problem is a more realistic case of the capacitated location-routing problem (CLRP) and belongs to the reverse logistics of the supply chain. The problem has many real-life applications of which some have been addressed in the literature such as management of liquid petroleum gas tanks, laundry service of hotels and drink distribution. The CLRP-SPD is composed of two well-known problems; facility location problem and vehicle routing problem. In CLRP-SPD, a set of customers with given delivery and pickup demands should be supplied by a fleet of vehicles that start and end their tours at a single depot. Moreover, the depots and vehicles have a predefined capacity and the objective function is minimizing the route distances, fixed costs of establishing the depot(s) and employing the vehicles. The node-based MIP formulation of the CLRP-SPD is proposed based on the literature of the problem. To solve the model, a greedy clustering method (GCM) is developed which includes four phases; clustering the customers, establishing the proper depot(s), assigning the clusters to depot(s) and constructing the vehicle tours by ant colony system (ACS). The numerical experiments on two sets of test problems with different sizes on the number of customers and candidate depots show the efficiency of the heuristic method with the proposed method in the literature. Finally, performance of the heuristic method to the similar methods in the literature is evaluated by several standard test problems of the CLRP.
    Keywords: Capacitated location, routing problem, simultaneous pickup, delivery, greedy clustering method, ant colony system
  • Seyed Farid Ghannadpour * Pages 237-264
    A new model and solution for the energy minimizing vehicle routing problem with time windows (EVRPTW) and customers’ priority is presented in this paper. In this paper unlike prior attempts to minimize cost by minimizing overall traveling distance, the model also incorporates energy minimizing which meets the latest requirements of green logistics. This paper includes the vehicles load as an additional indicator of the cost in addition to the distance traveled cost. Moreover, this paper tries to maximize the customer's satisfaction using their preference and considers the customer's priority for servicing. Every customer is assigned to a group (e.g., very important, important, casual and unimportant) and the customers’ preference is represented as a convex fuzzy number with respect to the satisfaction for service time. The detailed mathematical formulation of proposed model is provided and it is interpreted as multi-objective optimization where, the energy consumed and the total number of vehicles are minimized and the total satisfaction rate of customers is maximized. In general, the relationship between these defined objectives is unknown until the problem is solved in a proper multi-objective manner. Thus, a multi-objective evolutionary algorithm is proposed and its performance on several completely random instances is compared with Non-dominated Sorting Genetic Algorithm II (NSGA II) and CPLEX Solver. The hypervolume indicator is used to evaluate the two Pareto set approximations found by NSGA-II and the proposed approach. The performance proposed evolutionary is further demonstrated through several computational experiments and the results indicate the good quality of the method.
    Keywords: Vehicle routing problem, Energy Consumption, Customer's priority, Multi, objective, evolutionary algorithm
  • Danial Jahanshahi, Masoud Minaei *, Omid Ali Kharazmi, Foad Minaei Pages 265-283
    The purpose of this study is to evaluate the present status of Mashhad’s Bicycle Sharing (BS) Program's stations, and to locate future stations, taking into account the 7 criteria of “proximity to subway stations”, “proximity to other stations”, “distance from important intersections”, “distance from population centers”, “proximity to educational, recreational and commercialcenters”, “slope level” and “proximity to cycling infrastructure (bike lanes)”. The approach employed by the present study is Multiple-criteria decision making (MCDM) and Fuzzy membership maps and Analytic Hierarchy Process (AHP) based on GIS to weight the 7 mentioned criteria, also the stations will be ranked based on VIKOR approach and finally categorized through Jenks natural breaks classification method (JENKS). In order to analyze the data ArcGIS 10 software has been used. The findings show that 26 stations (20.3%) are very unsatisfactory and 25 stations (19.5%) are unsatisfactory among the total 128 stations that have been built so far. The findings also indicate that there are a lot of stations with very unsatisfactory conditions on the borders of the coverage area of the BS program which imply that widespread coverage has been prioritized over efficiency and proper distribution of the stations. Also 22 planned stations that have been stipulated in the contract between Mashhad’s municipality and the beneficiary firm have been located based on the ratings that were assigned. This study, as the first study with the mentioned approach on this subject in Iran shows that priorities regarding the performance of BS program may not be well conceived in different regions and cities, especially in developing countries with their own specific conditions. Thus, in this research we have tried to present the existing problems in locating the stations, and contribute to development of the existing programs and possible future programs in other cities.
    Keywords: Shared bicycles, relocating stations, GIS, VIKOR, Mashhad City
  • Mojtaba Moradi, Mohammad Mehdi Khabiri *, Mohammad Saber Fallah Nezhad Pages 285-303
    Air transport system has always been involved in all aspects of life because of its high potential in transporting passengers and goods. In this research we surveys the effects of travel variables on demand of domestic air transport, and for gathering required information from passengers, a questionnaire was designed including 20 effective parameters on air transport demand with questions These parameters were investigated based on their importance using “Factor Analysis” and finally proved that the factors “price paid by passengers”, ”services offered by air transport system” and “time” has had the greatest impact on air transport demand with more than 20 % influence. “Structural Equation Modeling” has been used for checking the “Factor Analysis” results. The results of the model proved the correctness of factor analysis. Furthermore, the result of factor analysis has showed that the most important parameter has been “low cost travel” with the factor load of 0.9-1 in all case studies. Results show that both groups with factor load of more than 0.5 in the obtained factors have identified the factor “services” as the important and effective factor with the influence value of more than 20%.
    Keywords: Air transport, transport demand, Factor Analysis, structural equation, travel variable