Environmentally appraising different pavement and construction scenarios: A comparative analysis for a typical local road

The aim of this work is to carry out a comparative analysis of environmental impacts for different scenarios of a typical local road. Life Cycle Assessment (LCA) is the modeling tool used to quantify and characterize comparative environmental impacts. In carrying out this specific application of the LCA, different road construction techniques were considered with regards to the whole structure and compared in order to identify the best alternative in terms of environmental sustainability.So far, in fact, typical LCA frameworks of roads have focused on recycled materials for pavement layers only, thus neglecting study of the materials used in the embankment or in the subgrade. In this study, these materials were included too, in order to prove the environmental benefit of using a sustainable technique such as in situ stabilization of fine soils with lime (typically dumped clayey soils) in order to reduce the need for virgin material for embankment and subgrade construction.When using different percentages of recycled materials (such as reclaimed asphalt pavement – RAP) in the bituminous layer or in the foundation, the analysis of the functional unit studied shows a significant reduction of energy consumption and pollutant emissions mainly due to transportation of materials involved, in this way increasing the environmental performance of the road.Another important consideration is that the use of fine soils stabilized with lime “in situ”, instead of dumping it, not only is a good technical solution for improving soil mechanical properties, but it also produces a reduction of energy consumption and of pollutant emissions. It is noticeable that this technique results in a significant reduction of pollutant emissions due the transportation of involved materials, increasing the environmental performance of the road.     

Quantifying the environmental and economic benefits of cooperation: A case study in temperature-controlled food logistics

Inefficient road transportation causes unnecessary costs and polluting emissions. This problem is even more severe in refrigerated transportation, in which temperature control is used to guarantee the quality of the products. Organizing logistics cooperatively can help decrease both the environmental and the economic impacts. In Joint Route Planning (JRP) cooperation, suppliers and customers jointly optimize routing decisions so that cost and emissions are minimized. Vendor Managed Inventory (VMI) cooperation extends JRP cooperation by optimizing routing and inventory planning decisions simultaneously. However, in addition to their economic advantages, VMI and JRP may also yield environmental benefits. To test this assertion, we perform a case study on cooperation between a number of supermarket chains in the Netherlands. The data of this case study are analyzed to quantify both the economic and environmental benefits of implementing cooperation via JRP and VMI, using vehicle routing and an inventory routing models. We found that JRP cooperation can substantially reduce cost and emissions compared with uncooperative routing. In addition, VMI cooperation can further reduce cost and emissions, but minimizing cost and minimizing emissions no longer result in the same solution and there is a trade-off to be made.     

Multiple criteria evaluation of transportation system improvement projects: The case of korea

As a newly industrialized country, Korea has shown remarkable economic progress in the last three decades. This phenomenal growth has rapidly increased demands for better quality of life. This includes, among others, increasing demand for high quality transportation system services. In this paper, the method of Analytic Hierarchy Process (AHP) is utilized to evaluate rural highway improvement projects in Korea. The appropriate rural highway improvement projects for widening and paving were selected and studied on the basis of some selection criteria. The results have shown that there are some significant differences in prioritizing projects using the traditional economic evaluation method as compared to those resulting from the use of AHP. As demonstrated, the AHP proves to be an effective tool in evaluating transportation system projects.     

Three-player game-theoretic model over a freight transportation network

With recent development in freight transportation industry, its network structure has become more complicated, as many decision-makers competing for profits with each other are involved. While most recent research in this area is focused on the perfectly competitive market and the prices are given as a constant tariff rate, little attention has been paid to the system optimization problem in the absence of regulatory authority. In this paper, we investigate the competitive equilibrium in an oligopolistic market on a freight network. A partially non-cooperative game among shippers, carriers and infrastructure companies (IC) is examined. All three kinds of players act as profit maximizing agents, except that the carriers and ICs are assumed to behave cooperatively in their own coalitions. We consider the vertically efficient nonlinear tariff schedules which are commonly used in the transportation industry. By introducing a three-stage game-theoretic model, we show that the equilibrium flows can also maximize total system profits if the IC and the carrier both use vertically efficient nonlinear pricing schedules. The division of the surplus associated with each shipment is obtained by solving a linear programming problem. We provide a few examples under different situations to show the existence of the resulting equilibrium.     

Determining vehicle dispatch frequency when shipping frequency differs among suppliers

Collecting is a way to consolidate freight that involves trucks picking up material from more than one supplier on each trip to a single destination. Earlier research resulted in a method that optimizes collecting vehicle dispatch frequency and that assumes that all suppliers are visited on each dispatch. This paper develops a method that determines the optimal dispatch frequency when large suppliers are visited more frequently than are small suppliers. This added flexibility allows the combined inventory and transportation costs of collecting to be reduced. The method is developed analytically and illustrated with an example.     

A NEW URBAN FORM AND ITS INNOVATIVE TRANSPORTATION STRATEGY TO ACCOMMODATE URBAN GROWTH

If we are to accommodate the rate of urban growth which North America will face in the first half of the twenty-first century, it is the contention of this paper that we must build new cities, not new towns, beyond commuting distance of existing cities. These can be located in open countryside on virgin land, or they can grow around existing small towns, all in conjunction with the construction of an innovative personal transportation system. In this paper a hexagonal modular structure, in which self-contained urban units can be combined and added to over time, is proposed as a new urban form and AVCS maglev — which will serve the new cities efficiently — is proposed as a key transportation strategy.     

Measuring energy and environmental efficiency of transportation systems in China based on a parallel DEA approach

Because of China’s rapid economic development, its transportation system has become one of China’s high-energy-consumption and high-pollution-emission sectors. However, little research has been done which pays close attention to China’s transportation system, especially in terms of energy and environmental efficiency evaluation. In this paper, data envelopment analysis (DEA) is applied to measure the energy and environment performance of transportation systems in China with the goal of sustainable development. This paper treats transportation as a parallel system consisting of subsystems for passenger transportation and freight transportation, and extends a parallel DEA approach to evaluate the efficiency of each subsystem. An efficiency decomposition procedure is proposed to obtain the highest achievable subsystem efficiency. Our empirical study on 30 of mainland China’s provincial-level regions shows that most of them have a low efficiency in their transportation system and the two parallel subsystems. There are large efficiency differences between the passenger and freight transportation subsystems. In addition, unbalanced development has occurred in the three large areas of China, with the east having the highest efficiency, followed by central China and then west. Therefore, more measures should be taken to balance and coordinate the development between the three large areas and between the two subsystems within them. Our analysis approach gives data for determining effective measures.     

Relationships among service quality,corporate image,customer satisfaction,and behavioral intention for the elderly in high speed rail services

Since the Taiwan High Speed Rail operations, Taiwan's transportation market entered into a new era. Because of its competitive service of speed, convenience, environmental concerns and comfort, the High Speed Rail has not only made significant changes but has played a significant role in Taiwan's transportation. However, Taiwan now is an aging society. Due to the physical constraints among the elderly, demands to redesign the traffic system and maintain transportation safety are essential considerations. In the current market, Taiwan's transportation construction is facing fewer barriers; however, it must still improve, especially considering the health of the elderly. Thus, this study investigates elderly passengers' demands and further examined the relationships among service quality, corporate image, customer satisfaction, and behavioral intention. According to empirical analytical results based on structural equation modeling (N = 341), satisfaction directly affected travel behaviors, while service quality and corporate image played indirect roles. In addition, service quality plays a significant role on the effect of satisfaction. This study provides empirical evidence to indicate the quality of the accessible environment affects not only the effectiveness and efficiency of service quality, but also, the corporate image. The results provide valuable references for critically managing the elderly's usage of the high speed rail transportation service. Copyright © 2011 John Wiley & Sons, Ltd.     

建筑垃圾再生砖混材料在路基中的应用研究

通过对建筑垃圾再生砖混材料的原材料和无机稳定混合料的性能试验,文章分析了再生材料的不均匀性、最大干密度、最佳含水率、CBR值等指标的变化规律,探究其作为路基填料的可行性。结果表明:建筑垃圾再生砖混材料的级配良好,同时吸水率较高,可以配合其他材料改善路基干湿状态;水泥和石灰均可有效提高再生砖混料的CBR值,且水泥稳定时对击实功变化较为敏感;再生转混料的整体性能完全满足规范对路基填料的技术指标要求,可以作为路基填料使用。     

试论沥青路面材料的再生工艺及专用机械设备的发展

沥青混凝土路面是目前国内外道路交通的主要面层结构,而沥青材料的热溶解特性,使沥青混合料能够较为容易地实现再生利用。作为节能减排和固废利用的重要组成部分,沥青混合料再生利用的工程规模及其技术进步也反映了一个国家或地区国民经济的发展和技术进步的总体水平。注重并优化沥青混凝土路面材料的再生工艺,并以符合技术条件的专用设备完成作业是路面材料高质量再生利用的前提和必要条件。     

Economic resilience to transportation failure: a computable general equilibrium analysis

This study develops and applies a multimodal computable general equilibrium (CGE) framework to investigate the role of resilience in the economic consequences of transportation system failures. Vulnerability and economic resilience of different modes of transportation infrastructure, including air, road, rail, water and local transit, are assessed using a CGE model that incorporates various resilience tactics including modal substitution, trip conservation, excess capacity, relocation/rerouting, and service recapture. The linkages between accessibility, vulnerability, and resilience are analyzed. The model is applied to the transportation system failures in the aftermath of Hurricane Katrina to illustrate its capabilities. The analytical framework, however, has broader applications and can provide insights for resource allocations to enhance emergent responses to unexpected events and to improve resilient design of transportation infrastructure systems.     

交通运输发展水平评价指标体系构建及优化研究

交通运输业是经济社会实现快速发展的重要保障,是实现国家和区域可持续发展的必要基础,承担着推动经济社会实现高质量发展的历史使命。本文介绍了交通运输发展的内涵,结合建成小康社会、生态文明建设、交通强国建设等战略目标对交通运输发展总体要求,对评价指标体系进行了初步构建。在此基础上对初选评价指标体系进行了"四个检验",同时运用变异系数、相关系数等方法进行了评价指标体系的优化调整。本文所研究构建的评价指标体系及优化调整方法可为行业管理部门开展相关工作、制定相关政策提供参考。     

Determining the Monetary Value of Quality Attributes in Freight Transportation Using a Stated Preference Approach

It is commonly accepted that the modal choice of a shipper is influenced not only by the pure economic attributes of transportation – time and cost – but also by more qualitative factors. These quality attributes relate to frequency, reliability, flexibility, transport duration and risk of loss or damage; they are usually difficult to quantify in monetary terms. Different techniques exist that help to understand better how these different quality attributes of freight transportation influence modal choice. In this paper we apply a stated preference design. Using real business data, the aim is then to derive partial utility functions that allow us to calculate monetary values for these different quality attributes.     

Assessment of an eastern European city's public transport system

The paper examines the present quality of public transport services in Budapest and compares that to the impact of growing car ownership. A review is made of the city's transport plans and future investment proposals and these are assessed in light of public transport's present and likely future competitive position compared to private cars. The paper concludes that much of the proposed investment in a metro system will not maintain public transport's competitive position in the face of rising car ownership and that other measures and investments might be more effective.     

Time-dependent fuzzy random location-scheduling programming for hazardous materials transportation

The tremendous use of hazardous materials has promoted the economic development, which also brings about a growing risk causing a widespread concern. In this work, we consider a location-scheduling problem on hazardous materials transportation under the assumption that transportation risks are time-dependent fuzzy random variables. First, we formulate a scheduling optimization model and design a fuzzy random simulation based genetic algorithm to optimize the departure time and dwell times for each depot–customer pair. Then we establish an expected value model and design a modified particle swarm optimization algorithm to minimize the en route risks and site risks. Finally, numerical examples are given to illustrate the effectiveness of the proposed models and algorithms.     

Demand management as an element of transportation policy: using carrots and sticks to influence travel behavior

This paper describes the characteristics of transportation demand management. The origin of transportation demand management (TDM) as it has evolved in the US is related to federal policy initiatives that first focused on improving the efficiency of the urban transportation system through operational improvements, and then incorporated concerns such as air quality and energy conservation into the transportation planning process. The paper then examines the effectiveness of TDM actions, and concludes that those actions most likely to increase the “price” of travel for single occupant vehicle use will be most effective. The paper identifies several strategies for improving the effectiveness of TDM actions in the context of regional transportation planning, including: incorporating TDM as part of the solutions for regional transportation planning, linking TDM to land use decisions, making the costs of travel more apparent to the user, and making TDM implementation more palatable to the general public.     

AN APPROACH TO THE ECONOMIC APPRAISAL OF AVCS MAGLEV

The purpose of an economic appraisal of a transportation project is to help select an efficient transportation investment plan. Here, efficiency means achieving the best transportation service from a given investment and the generation of net benefits at least as great as the costs of the investment. In this article, three future transportation investment alternatives in the USA are compared using the benefit-cost ratio method to illustrate the economic desirability of the AVCS Maglev alternative – an advanced vehicle control system based on magnetic levitation and propulsion. For the completeness of the economic appraisal and the provision of a guide to performing non-user benefit analysis for this promising ITS technology, the socioeconomic effects of implementing AVCS Maglev in the USA are evaluated based on the US National Development Model (NDM).     

Parking preferences among tourists in Newport,Rhode Island

Like many tourist destinations, Newport, Rhode Island relies upon high season tourist volumes for its economic health. Most visitors arrive by car, concentrated during certain hours on summer weekends, severely congesting the town’s major arteries and forcing many visitors to spend considerable time in their car. A transportation planning strategy which reduced congestion would enhance the quality of the visiting experience, increase the time visitors are able to spend in shops and at attractions, and draw additional visitors. However, identifying effective solutions requires understanding factors that affect tourists’ transit choices. We develop a conceptual model of Newport visitors’ parking and transit choices, expanding traditional transit choice models to include features such as scenery we expect to influence tourists. Using a stated preference survey of visitors, we find scenery, transit mode options and congestion are the major drivers of tourists’ parking choices. We also develop welfare estimates to enable analysis of proposed transportation plans.     

Simulation model performance analysis of a multiple station shared vehicle system

As an alternative transportation paradigm, shared vehicle systems have become increasingly popular in recent years. Shared vehicle systems typically consist of a fleet of vehicles that are used several times each day by different users. One of the main advantages of shared vehicle systems is that they reduce the number of vehicles required to meet total travel demand. An added energy/emissions benefit comes when low-polluting (e.g., electric) vehicles are used in the system. In order to evaluate operational issues such as vehicle availability, vehicle distribution, and energy management, a unique shared vehicle system computer simulation model has been developed. As an initial case study, the model was applied to a resort community in Southern California. The simulation model has a number of input parameters that allow for the evaluation of numerous scenarios. Several measures of effectiveness have been determined and are calculated to characterize the overall system performance. For the case study, it was found that the most effective number of vehicles (in terms of satisfying customer wait time) is in the range of 3–6 vehicles per 100 trips in a 24 h day. On the other hand, if the number of relocations also is to be minimized, there should be approximately 18–24 vehicles per 100 trips. Various inputs to the model were varied to see the overall system response. The model shows that the shared vehicle system is most sensitive to the vehicle-to-trip ratio, the relocation algorithm used, and the charging scheme employed when electric vehicles are used. A preliminary cost analysis was also performed, showing that such a system can be very competitive with present transportation systems (e.g., rental cars, taxies, etc.).     

Structural equation modeling for national travel demand: an examination of the relationships between communication modes

This paper examines the relationships among different transportation modes, and between transportation and telecommunications, by applying the structural equation modeling (SEM) technique. For this purpose, we collected and compiled time series data on national travel demand, and socioeconomic and telecommunications conditions in Taiwan, and built national travel demand models using SEM. The estimation results show that the relationship between telecommunications and transportation demand (either car ownership or public transportation) is more complementary than substitutional. Moreover, car ownership is a type of inelastic necessity good, and its relationship with public transportation is more substitutional than complementary. Finally, among the three public transportation modes – rail, bus and domestic air – it is found that air is weakest in terms of competitive power. From the viewpoint of long-term forecasting trends, the bus holds its competitive power in comparison with other public transportation modes and would not be replaced in the future.