پژوهشنامه حمل و نقل
سال پانزدهم شماره 1 (پیاپی 54، بهار 1397)

Transferring of containers from road to rail network leads to some advantages such
as: reducing fuel consumption, air pollution and road accidents. Construction of Dry Ports has a significant role in the development of multimodal transportation and use rail and road system advantages. In this paper a new Hub Location problem (HLP) in combination with Data Envelopment Analysis (DEA) is presented from standpoint of rail system on a rail-road multimodal network. The indices that are considered in DEA, are provided from HLP outputs including rail routes ' volume, rail container kilometer and rail routes ' length. The proposed model was implemented on Iran container network and 40 different scenarios based on the number of dry ports (2 to 5) and percent discounts on rail routes (0% to 90%) were evaluated. The results showed constructing two dry ports with considering 0%, 10% and 30% discount on rail routes are as efficient scenarios. Comparison of proposed location's facilities demonstrated constructing two dry ports in Tehran and Sirjan and applying 10% percent discounts on rail routes is the optimal scenario. In this scenario the rail routes ' volume, rail container kilometer and rail routes ' length were equal to 780 thousands TEU, 716 million TEU-KM and 3731 KM respectively.

One of the most influential properties of a pavement, which can completely change the coating performance, is the shear bonding of the layers. Many experiments have been conducted to measure this resistance, but there is no standard test for measuring this shear strength. One of the most realistic methods for evaluating the shear properties between the pavement layers is the evaluation of the shear stiffness, as well as the loss of the shear stiffness between the pavement layers under cyclic loading. In this research, a pilot experiment in the Amirkabir University of Technology, conducted using a machine called AUT-SLT. The repeatability of the results was statistically evaluated and also compared with the results presented in previous research. The results of statistical tests indicate the repeatability and also the similarity of the diagram form with the previous research charts. Accordingly, the AUT-SLT test can be used as a repeatable and reliable test to find the shear stiffness values in geosynthetic reinforced pavement samples.

In this paper, defining a probable earthquake, a calculating measure as transportation accessibility level was presented. After data collecting include: road network, population, building, seismic risk, hospitals; an appropriate network for analysis based on GIS environment was prepared. By determining centroids of each district (totally 32) zone as an origin was selected and the health service center (totally 45) as a destination was determined. Travel speed (in the of range 5km/h - 20km/h) was assumed. Road blockage caused by collapsed building was simulated with point barrier, line barrier and polygon barrier in GIS environment. According the result of network analysis in periods (10, 15, 30, 45 minutes) access to any health service and changing the accessibility by time has been shown. The analysis was performed with blockage condition; the results showed that the accessibility index significantly dropped but the changing index with barriers was similar to without barriers. Moreover, the change rate of entire index in the network without blockage comparing network with blockages links is more sever.

Urban transportation is regarded to be the major foundation of sustainability. As a matter of fact, transportation is pivotal in our life and a great challenge we encounter with. As the old texture of neighborhood experiences different problems such as social physical and economical ones, the visual and physical access feasibility promote the level of environment quality indices. The paper at issue is applied in terms of method and analytical-descriptive. The data collection was from library documents and field studies. This paper aims to investigate the necessity of sustainability of transportation in Zandha neighborhood in Hamedan to improve environmental of quality. With the review of theoretical literature, this paper seeks to answer the question how important monitoring transportation indices can improve the urban environment quality. First, the sustainable transportation indices were extracted along with urban environment indicators. Then, using binary check list of urban design, the relationship of indices was determined. The findings show that sustainable transportation indices can increase the quality of urban environment. The environmental quality, pedestrian, orientation and security had the greatest impact, respectively.

While parents are the ultimate decision makers for their children’s mode choice for school trips, their mode choice in return is under the influence of their children’s trips requirements. This paper demonstrates how an integrated model describes transit usage for commuting trips –both work and school trips- in households. A sample of size 4000 households (return rate 47.39 percent) was surveyed via physical questionnaires. Respondents had necessarily at least one child at primary school. Descriptive statistics of data showed only 732 (39 percent) of them use transit for work trips and 216 (11percent) of children use transit for school trips 3 times a week or more. A structural equation model, inspired by theory of planned behavior was utilized to explore a single model explaining transit usage in households. Results emphasis on the intentional aspect of transit usage. Perceived behavioral control showed to be effective as well. Additionally habit, access to transit infrastructure, escorting child to school and distance from home to school showed to be significant.

Nowadays, railway slab track are widely used in the world. Although according to the railway standards, design process of railway slab track should be performed as design procedure of road rigid pavements, there is no sign of design classical method of the slab track. To respond this need, this research is carried out. AASHTO method is one of the design methods of road rigid pavement. In this paper, to develop a method of slab track design process, some modifications were made in the AASHTO method. The results obtained in this study indicate that the slab track thickness is dependent on the traffic volume, existence of concrete shoulder and subgrade stiffness. When the subgrade stiffness increases 24 times, the slab track thickness decreases 10 percent. Moreover, when the traffic volume was increased 2 and 4 times, the slab track thickness was increased 12 percent and 25 percent respectively. Additionally, the slab track thickness was deceased roughly 5 cm when the concrete shoulder was considered adjacent to the track.

Nowadays¡ with the increasing development of urban¡ population growth and increasing traffic congestion¡ parking shortages of vehicle especially in inner cities¡ suffered most big cities are. Public parking as a component of o modern urban transportation system¡ parking task level¡ to remove static traffic of urban communication system and thus reduce traffic congestion and traffic level are the center of the city. Geospatial information system (GIS) that are science and technology in analyzing spatial dara¡ an appropriate system are considered to find the most optimal place for public parking construction. In this study¡ factors affecting in site selection of public parking studied & analyzed away from four perspectives: centers of travel¡ distance from the street¡ value of the property & appropriate users. And the selection criteria were and weighted surveyed by using analysis hierarchical hierarchical paired (AHP) in expert choice application. And after preparing the information layers in GIS environment¡ these criteria¡ combined to each other with module of raster calculator and at the same time¡ calculated weight applied from AHP process to layers. And 15 sites were proposed for the construction of parking. The study also found that the optimal placement of Babolsar city does not have vertical parking available.

All transportation specialists agree to achieve the sustainable transports pattern in cities. Public transportation plays a crucial role in sustainable transport. It is necessary to do some proceeding for improvements of management and increase productivity, in order to increase its share out of urban transport. In this context, the most important step in changing of bus transit systems quality is modifying or redefining of the lines route. This process is known as strategic step for long-term program management. In this research, 9 effective parameters has been selected to present a model for Determining the optimal route of bus lines on the basic of data Khomeini-shahr of Isfahan which its goal is increasing coverage of bus network in cities, as well as reducing the number of parallel lines in streets. These parameters include Population covered every street, passengers, Type of roads, Level of service, Speed, Facilities of each station, Available density, Land use and length of each link.The selected parameters are weighted according to the impact of the problem, by Analytical Network Process and number of expert ideas, Afterword, the obtained weights are entered in the Network Analysis extension to do New Route operation. Consequently, a new network is established which changes 20 lines of the existing network, increases network coverage more than 18000 persons and declines 22 km overlap of the lines.

Transport industry is one of the important and economic elements of each region. Because, in addition to that it is considered as an important and fundamental part, it affects many other activities of the societies and provides the possibility of appropriate productivity of potential capacity of the country. It is important that which province has more capacities in this industry and may help the managers in making better decisions to allocate resources and facilities and develop planning. Despite the importance of this industry, there has been little study about ranking the provinces in this industry. The aim of this research is to evaluate and rank the provinces in the field of transport. For this purpose, firstly, transport industry is divided to four parts of air transport, sea transport, freight transport, and passenger transport. For each part, appropriate indexes have been determined according to the library studies and interview with experts, and data are derived from valid statistical references. Then, indexes weights have been calculated by using Shannon Entropy in each part and then, with regard to the operation in each of the four parts, the provinces were ranked by using Taguchi Loss Function. This research is a descriptive analytical one, research domain is all provinces of the country, and the time period is the year 2012. According the results, in passenger transport, Semnan Province received the first rank and Yazd Province received the last rank. In freight and air transports, Tehran Province won the first rank and Golestan and Esfahan Provinces respectively had the last rank in these two parts. In sea transport, Hormozgan Province was in the first rank and Khuzestan Province in the last one.

Capital as an important element in production, a decisive role in the production process of whole economic sectors. Besides, regarding the importance of growing transportation network and its impression on the economy, investment in this division significant role in the growth and prosperity of the irans. Hence, in this paper the beginning of the incremental capital output ratio was used and explained that, for rail transportation sector in the period 1975-2012, the incremental capital output ratio has been figured. The subject of investment in rail transportation sector value added growth with the neoclassical growth model And model Vector Auto Regression and software is estimated Micro fit and Eviews. The results of the calculation of the incremental capital output ratio show that this ratio is equivalent of 1.084 and This means that for producing a billion rials value added in rail transport section need to invest equivalent 1.084 billion rials is necessary. The results of the estimation show that an increase of one percent in the ratio of investment made in the rail transport sector on the gross domestic product this section will be Increase the value added growth rate of 0.315 percent.

The purpose of this study is to investigate the behavior of notched asphalt sections by using semicircular bending test. To do this, in order to adapt the test conditions to real conditions, a Haversine loading with two different loading duration and a rest period with a ratio of one at a constant temperature of 20°C was used. Asphalt specimens used in this experiment are in two different grading with a nominal maximum aggregate size of 12.5 mm and 25 mm. In order to carry out the investigations, the vertical displacement and crack opening in each loading cycle were recorded and analyzed in two stages of loading. The results showed that in both loading stages, the effect of the maximum diameter of the aggregates on the vertical displacements and the crack opening depended on the loading duration (speed). In the shorter loading duration and the first loading stages, the mixture with the smaller aggregate diameters and, in the second loading stages, the mixture with larger aggregate diameters, exhibited a better resistance to the rutting. In both stages of loading, crack propagation is faster than vertical displacement, which can indicate a faster growth of fatigue cracking than rutting in notched sections.

Companies in a competitive environment are constantly need to generate new offers to their customers, so they have to constantly change their business model or accept to loss their market share to other competitors. In this regard, rail freight companies are no exception and need to upgrade their business model with new ways. Since the country's vision document has set the transportation volume for freight sector equal to 91 million ton on the horizon of 1404, it is needed that the business model be constantly redesigned to achieve this goal. To redesign the business model, it is necessary to fully identify the dimensions and components of the model, which is dealt with in this regard. After literature review, 9 general and 7 special interviews were held with the experts. The content analysis method was followed and then open/axial coding done and 122 components were extracted for the business model of the freight railways companies. Instead of conducting selective coding, by examining the literature, different business models were extracted and, taking into account the components of the research, 10 dimensions were chosen to cover all the components. Due to the high number of components, two Delphi stages were performed by using 7 internal and external specialists and the final components were obtained by consulting to them. CVI and CVR are also calculated using 8 other experts and the total number of the components is reduced more. Finally using 6 other experts from the field of rail and using the ISM (Structural Interpretation Modeling) method, an interactive model has been obtained among dimensions.

One of the key issues in the operational management of the supply chain is the inventory routing problem, which is a combination of inventory management and transportation planning. According to the literature review, this paper combines one of the practical features of routing problem named as "backhauls" with the multi-product, multi-period, multi-Vehicle inventory- routing problem. The stock out and backlogging is not allowed in this model. The Strategy of routing is Multiple Delivery Strategy. This problem is non-deterministic polynomial-time hard (NP-hard) and the solution time, using the exact methods, increase exponentially with the increase in the dimensionality of the problem. Therefore, after introducing the research background, a new mathematical model is proposed in the form of the mixed integer programming for the problem defined in this paper. As follows, an efficient meta-heuristic genetic algorithm is provided to solve it. At the end, the numerical results obtained by this algorithm are analyzed using the randomized testing problems.

Today's traffic situation especially in big cities, makes the deployment of public transportation the best solution and the people should persuaded to use it, it requires reducing the travel time by public transportation. The skip-stop plan is one of the accelerator programs for urban train systems that, once examined, and if affordable, will be able to run with the lowest cost of infrastructure. As the trains in the line are divided into two types A and B, the stations are divided into three types A, B and AB according to the passenger traffic volume. Each train, in addition to stopping at its equivalent stations, stops at AB stations and skips to other stations. In this research, we have attempted to optimize the implementation of optimal skip schedules to optimize travel time. So, after entering into the relevant information, a program is written and presented to offer best practices for subway lines. A case study was also conducted on line 2 of Tehran Metro and finally the best way to implement this plan was proposed.

The vehicle emissions mainly depend on the amount of consumed fuel, type of fuel and traveled distance. One way to combat with greenhouse gases and air pollution associated with oil consumption is to use alternative energy sources. However, the lack of infrastructures such as refueling stations is one of the major barriers to the adoption of alternative-fuel vehicles. In this study, as an operational approach for transition period, we propose a model to extend the vehicle routing problem to green vehicles. This is a NP-Hard problem, and consequently it is very difficult to solve the real-world instances. Therefore, we propose a solving method based on benders decomposition that equipped with a set of valid inequalities. Implementation of proposed algorithm on randomly generated problems leads to acceptable results in a reasonable time.

School travelling is relatively undeveloped in transport research. More researchers hast identified the socio-economic and environmental characteristics on choice of school travel mode. The main purpose of this study is to determine the role of Psychological factors (latent variables) on school service mode. This study uses a dataset gathered in January 2015 in Mashhad, from 28 elementary schools (including public and private, boys and girls schools) and 820 questionnaires are filled out by the parents. A Structural equation model (SEM) is built by 625 records in AMOS software. SEM results shows that parents who are strongly worried about pupils while walking are more likely to choose school service for school trips. Parents who are highly worried about using school service had the negative effect on choosing school service. The Results suggest that perceived travel time, child birth order, risk perception, perception of environment, children’s competence and cultural factors are all statistically significant in children school service mode choice.

In this research, we investigate the effective factors and types of pavement deteriorations affecting the number of crashes, including skid resistance, international roughness index (IRI), rutting, cracks, potholes, lane width, average annual daily traffic (AADT), length of segment and speed of vehicles investigated in 19 main urban centers in Tehran province and analyzed using SPSS software. Since investigating the effect of maintenance activities on crash reduction, was the other objective of this study; the mentioned relationship was re-evaluated after the maintenance activities. The regression model revealed a significant drop in crash rate. The results indicate that the deterioration of the pavement and among them the IRI are highly effective in crashes and the maintenance activities reduced crashes in the network by 60%. Since the present research is in the network level and all of the roads in the province of Tehran are considered, they will lead to proper management results. Based on the initial research questions, it can be concluded that there is a significant correlation between crash fatal, pavement deteriorations and traffic. Furthermore the developed relationships could be manipulated to predict after maintenance crashes. The pavement deteriorations and consequently the pavement condition are highly effective in crashes. It should be noted that these crashes are pavement-origin and the rate of reduction is also related to pavement-source accidents. Two regression and logarithmic analysis methods were used to match the variables by distributing existing models. Results revealed that the amount of crashes after maintenance has reached about 0.40 and 0.52 times the state before the maintenance activities, for regression and logarithmic analysis method respectively, which represents 60 and 50% reduction in crashes caused by deteriorations of pavements.
Existing enough entry data, both models are capable to predict crashes. The regression model is superior with 10% reduction in crashes.

Aggregate gradation of asphalt mixture that makes up the backbone of the main structure and is the most important factors in making resistance of pavement damage. Stone materials constitute a large percentage of a hot asphalt mix. As a result, a mixture of rocky material properties have an influence on properties of provided mixed. The present study with the title of technical analysis of using Dense, Gap and porous Gradation of aggregation in hot mix asphalt is one of the first studies in which three types of gradation open, continuous and porous asphalt concrete construction, are compared with each other. In this study we aim to do is to improve the life and performance of asphalt in the country and especially in Bushehr province by using of common aggregation in Iran and determining the appropriate aggregation in Hot Mix Asphalt used in road network of the province. To obtain optimum bitumen, Marshall Tests was performed on 108 samples of Examples of aggregate blende with the number of 6 percent bitumen. As a result, according to Marshall Charts, Marshall Strength in the aggregate mixture prepared with optimum bitumen in aggregation porous more than any other type of aggregation and mental Marshall Grading Type continuously aggregation was lower than the other. Marshall also the most difficult to mix aggregation type porous No. and the lowest gradation is open number.

In financial literature, price volatility or any variable is an indicator of the risk of that variable, and it is usually calculated using standard deviation or variance. Accordingly, the purpose of this paper is to analyze the structure of volatility of freight rate in the dry bulk and tanker markets. In order to, examine the structure of the volatility of BDI, BCTI and BDTI indices; full autoregressive conditional heteroscedasticity was used. The results of the research showed that there was high volatility in all three freight markets. Also, the results of the Minimum durability of the memory of a shock in the BDI index indicate that during the volatility of prices, the freight risk of this market will much less than the other two markets. So, and according to Markowitz theory, investors who intend to buy dry bulk or oil tankers shipping companies stocks, if they intend to maintain stocks in long-term and work strategically in the stock market, buying stocks of dry bulk shipping companies will be less risky for them.