Existing Transportation System Research Articles

Potential for Expansion of the Special Forest Products Industry in the Northern Rockies

Abstract The special forest products industry has the potential of making substantial contributions to the troubled forest-based economies of the Northern Rockies. Comprised of floral greens, Christmas ornamentals, wild edible mushrooms, other edibles and medicinals, and Pacific yew segments, the industry has the potential to provide both full-time and part-time employment on a nearly year-round basis. The region's natural resource base and available labor supply seem well-suited to developing special forest products firms. The existing transportation system and business environment is also well suited to expansion of this industry. West. J. Appl. For. 10(4):138-143.

Aeroacoustic sources of high speed maglev trains

Noise has been identified as a potential source of concern associated with the introduction of high speed maglev trains into the existing transportation system in the United States. The first operational maglev systems have been shown to generate high noise levels at high speeds, with noise levels over 100 dBA at 25 m typical for the maximum cruising speeds. At speeds greater than 150 miles per hour, the dominant noise source is of aerodynamic origin, proportional to the 6th power of velocity at high speeds, and 8th power dependency at very high speeds. An investigation of the noise generated by maglev systems was conducted to determine noise sources, develop noise criteria for high speed maglev systems, prepare design guidelines for noise control, and recommend an acoustic test facility for maglev research. This paper describes the findings of the study including recommendations for further research to develop a better understanding of the aerodynamic sound generation associated with high speed maglev operations. [Work performed under contract to U.S. Department of Transportation as part of the National Maglev Initiative.]

An activity network approach to introducing alternative transportation systems

This paper investigates an incremental, cost-effective transition process from an existing transportation system to some improved system. The goal of the process is to speed introduction and transition, compared to gradual evolutionary change, by identifying technologies and feasible pathways. A graphical technique is outlined that combines engineering benefit/cost analysis and precedence diagrams from project management. The approach defines and evaluates potential technologies and relationships among the technologies. The introduction of each technology can be broken into development, implementation, and market growth activities, which are represented on activity networks along with activities for other related technologies. The resulting activity networks can be used to plan and evaluate transition pathways. A market range can be calculated for each technology, based on expected benefits and costs, showing when the technology should be deployed and when it should be replaced. Since each activity has associated time, cost, and resource estimates for completion, scaled activity networks can also be drawn. The most useful diagrams are two-dimensional, with time on the horizontal axis and market level on the vertical axis. These scaled precedence activity network (SPAN) diagrams show the market range for each technology and how soon each technology can be deployed. Logical strategies for introduction, which span the expected market range by using a combination of several technologies, can then be identified from the SPAN diagrams. These deployment strategies, selected by matching the level of deployment of technologies with the market level, provide a means of reducing the investment risk of introducing alternative systems.

The application of a computer program to the analysis of sugar cane transport— a case study

Earlier work by the author was concerned with the production of a computer program which predicted the performance and operating costs of transport vehicles in the smallholder and estate sectors of developing countries. The program has been increased in scope and, from the same fundamental basis, now produces additional economic predictions concerned with system profitability and the cost-benefits of change. The application of the program to the analysis of a sugar cane transport system in a developing country is described. It was found that initial predictions of performance and costs were substantially lower than those found in practice, but during later phases it was established that this was accounted for by discrepancies in some of the data supplied. Factors of particular significance were vehicle utilization, equipment capital cost and the cost of spares and repairs as a proportion of depreciation. The initial program outputs were useful in challenging suspect data and subsequent data revisions produced a reasonably close match between the computer predictions and actual performance of the system. The program was then used to model the cost effectiveness of upgrading the surface standards of roads in the factory catchment area. Upgrading was not likely to be justifiable except under closely defined conditions in the central area. It was concluded that the program can be useful in modelling an existing transport system with a view to subsequent investigation of the likely benefits of changes in vehicle or condition specifications.

Modeling the Choice of Work Schedule with Flexible Work Hours

Flexible work hours have been promoted as a low cost approach to improve the productivity of the existing transportation system. However, analytical tools are needed to evaluate the impact such policies have on workers' arrival time choices. This paper develops a behaviorally based structure, using utility maximization concepts, to relate travel, family, workplace and individual influences to the workers' choices of arrival times with flextime. The accuracy of this conceptual structure is explored through the development of disaggregate probability distribution models using maximum likelihood estimation techniques. These models investigate several specifications and examine the use of market segmentation to differentiate varying work arrival time behavior by different subsets of the population. Major findings include: older workers and those living at greater distances from the workplace tend to arrive earlier, and households constrained by the presence of a working spouse and young children have less flexibility to alter arrival times with flextime.

Types of transportation supply functions and their applications

The purpose of this paper is to clarify concepts of the relationships used to describe the supply of transport services in network flow equilibrium models. These functions are used to describe the capacity, level of service, and price characteristics of transportation systems. There appear to be three types of supply relationships, and these are identified and discussed with examples from the existing transportation system literature. Finally, the possible uses of each of these types of supply relationships are discussed, along with areas of needed research.

Comparison of Rapid Transit Planning Efforts

The recent major rapid transit planning efforts of four medium sized metropolitan regions were reviewed. Comparisons are made of existing characteristics, planning procedures, and the recommended guideway proposals. Major technical considerations that led to the proposals are also reviewed. Existing characteristics are introduced first, including political structure, demographic information, topographic features, existing transportation facilities, and transit usage indicators. Next, each region's varying approach to rapid transit planning is examined. The identification of the priority guideway corridor, the selection of the first segment for implementation, and the evaluation of technologies are all reviewed for each area. Recommended proposals are described that emphasize facility type, patronage, and cost estimates. To enhance the understanding of these programs, major technical considerations are highlighted. These include unique aspects of transit ridership forecasts, benefit-cost estimates, existing transportation system analysis procedures, and citizen participation programs.

Assessment of use of public transport in cities by elderly and disabled persons

The public transport system is one of the key factors determining the economic and social development of modern cities, faced with the goal of providing convenient connections between different areas of the functional structure, i.e. ensuring high comfort and short travel time, while minimizing environmental impact. However, it is worth asking: is creating such a transport system possible, does it exclude certain social groups, and is it capable of satisfying the needs of all users? More and more modern planners and transportation engineers are facing this dilemma. According to many scientific publications, universal design is the answer, hence shaping public spaces and the transport systems with awareness of the diversity of the human collectivity in terms of sex, age, physical ability and health condition. Elderly people above 60 years of age and the disabled, who have various types of mental, physical and sensory dysfunctions, are at the greatest risk of social exclusion. These groups of people encounter many architectural and transportation barriers in their daily lives that make it impossible for them to move freely, thus limiting their access to education, employment and culture. Only through analysis of the existing transport system, identification of transportation barriers, and the appropriate decisions to eliminate them can this exclusion be counteracted and a city without barriers be created – a free city where every resident can move easily, whether they are blind, hard of hearing or a wheelchair user. This article defines the concepts of elderly and disabled people and presents the barriers most frequently encountered in city transport systems. Moreover, guidelines for designing a transport system according to the needs of the analyzed group are proposed. The results of survey studies conducted in Oswiecim and Cracow concerning assessment of public transport and its adaptation to elderly and disabled people are a significant part of this article. Results and conclusions obtained from studies can be an inspiration for other cities that want to create a transport system adapted to the needs of the analysed group, however it is also worth remembering that shaping public spaces and transport “for everyone” is only possible by engaging all parties interested in the problem, i.e. above all, elderly and disabled people as well as city authorities, and then making every effort to reach a consensus between these groups.