Attitudinal models of modal choice: The multinomial case for selected nonwork trips

Attitudinal multinomial logit models of modal choice are presented for four nonwork activities: major grocery shopping, shopping for odds and ends, shopping for personal goods and visiting friends and acquaintances. Explanatory variables are individuals' beliefs about attributes of four modal alternatives: bus, car, taxi and walking. Factor analysis is employed to identify latent dimensions of perception of the modal alternatives and to eliminate problems of multicollinearities in model estimation. Models are estimated using data obtained for a sample of residents of Buffalo, New York. Planning implications of the methodology are assessed.This author is presently Systems Planner with Applied Resource Integration, Ltd., Boston, Massachusetts.     

A comparative study of the dynamic behaviour of a fast patrol boat travelling in rough seas

This paper describes a comparative study between full scale measurements recorded on a fast patrol boat encountering heavy winter seas, south of the Isle of Wight and theoretical predictions accounting for the slamming behaviour of the flexible hull. A hydroelastic approach is adopted and satisfactory agreement between measured and predicted responses demonstrated.     

先进的交流电传动现状和展望

始于上世纪70年代初的交流电传动技术已经从晶闸管技术发展到GTO技术.交流电传动技术的不断成熟,使其真正成为所有新机车动车的标准.在最近几年中实现了IGBT取代GTO晶闸管的重要技术转型.作为最新进步,该技术转型现在还涵盖了大功率应用范围.德国铁路公司新型的BR189四电流制电力机车最早将该项革新技术应用于极限功率范围.新的交流传动调节方法SITRAC融合动力学、耐用性和具有自调节的最佳调制为一体,其运行可不用速度传感器.展望未来以及铁路工业试验室不断加强对超导变压器、静态能量储存、无传动齿轮箱的直接传动和燃料电池的前景的关注,这里不仅是考虑能源价格的日益增涨.预计在2010年前一些革新技术将用于铁路中.     

The structure of intercity travel demands in Canada: Theory tests and empirical results

This paper presents results of an econometric study study of intercity travel demands in Canada, 1961–1976. A translog form of reciprocal indirect utility function is used to test the structure of preferences in five demand sectors: three travel modes, goods and other services. Travel sector preferences are found to be time- and season varying but independent of average weekly work hours. The aggregate results indicate that the demands for all three passenger modes are price-elastic; bus and rail exhibit moderate complementarity, while rail and air are weakly complementary. The most important result derived from our tests of separability was that the demand system for the three passenger modes is inextricably tied to the rest of the economy, and therefore, may not be studied in isolation from the goods and other services sectors.     

Container shipping in 1990

By 1990 express shuttle container ships will dominate the USA/North European and USA/Pacific trades. The pattern is already apparent in the Pacific. These will touch only a few ports such as Halifax, New York and Virginia on the Atlantic and Los Angeles/Long Beach, Oakland and Seattle/Tacoma in the West. Their low costs and good services will capture over 80% of available general cargo. Round the world systems will be left with lucrative fringe business in the Mediterranean, US Gulf/South Atlantic, Singapore, India and Arab countries.

Progress will be sensitive to twelve trends. Most important of these will be labour resistance and management concerns about rapid obsolescence of ships and terminals. Rail and ship costs have been rationalized and are not as flexible as terminal costs. The ultimate terminal will consume about one third of the time and money presently needed.

This paper is chiefly intended to suggest a forecasting methodology.     

The role of congestion of transportation networks in urban location and travel choices

Congestion of urban transportation systems results from an equilibrium of location and travel choices with generalized travel costs which increase with vehicle flows as well as other factors. The use of network equilibrium concepts in analyzing urban policies and evaluating alternative plans is examined. Issues arising in the use of network equilibrium models are described, and formulations of urban network prediction and design models are explored.     

Bus accidents,bus deregulation and London

Local bus services were deregulated in October 1986 in all areas of Britain except London. Government policy is to extend deregulation to London, though not in the current parliament. This paper analyses statistics on bus accidents from the national road accident database from 1981 to 1991 to compare results for London and the rest of Great Britain, and to consider whether deregulation has affected safety. The conclusions depend on the assumption that accident recording practice was not itself affected by deregulation.Bus accident rates are higher in London than on built-up roads elsewhere, partly apparently because of road traffic conditions in London, and partly because open-platform buses have higher accident rates involving occupants, including boarding and alighting accidents, than buses with doors.The main safety effects of deregulation operate through its effects on bus activity, though there is also some evidence that the rate per bus-kilometre of accidents involving other road users fell slightly. This may be due in part to the trend towards smaller buses associated with deregulation. Deregulation has led to a fall in bus patronage, and thus to a fall in occupant casualties; and to a rise in bus-kilometres, and thus to a rise in casualties among other road users in accidents involving buses. The number of fatal and serious casualties among other road users involved in bus accidents is larger than the number among bus occupants, so deregulation in London could lead on balance to a small rise in fatalities involving buses. On the other hand, the number of slight casualties among other road users involved in bus accidents is smaller than the number among bus occupants, so deregulation in London could lead to a fall in the number of slight casualties involving buses.Although there were fears that changes in the management of bus operations or financial pressures might lead to increased accident rates following deregulation, there no evidence in the findings to support such fears.This paper was first presented at the 3rd International Conference on Competition and Ownership in Surface Public Transport at Mississauga, Canada on 25–29 September 1993. The author is grateful to the Department of Transport for the speed and efficiency with which they provided special tabulations from the road accident database for this study.     

The case for using cost benefit analysis to evaluate the supply of public goods in the maritime industry

In an era in which economists have rediscovered their belief in the economic efficiency of free markets and espoused privatization as a policy means of achieving these benefits, perhaps it is advisable to consider some of the difficulties markets have in supplying public and merit goods. In the following article, the case of the Hydrographic Service safety services and the difficulties of using traditional accounting methods to assess the adequacy of that provisions. It is also argued that the techniques of cost benefit analysis should be used to assess the adequacy of the supply of public goods and a framework is suggested for the evaluative structure.     

Transit system evaluation: Guideway bus vs. light rail transit

This paper describes a set of specialized spreadsheets that model the cost and performance of transit system options including light rail transit, guideway bus, express bus, and ride sharing. These spreadsheets are demonstrated by comparing a guideway bus (GWB) transit system and a light rail transit (LRT) system proposed for construction in an active rail corridor. The comparisons for assumed levels of transit ridership include guideway geometry, travel time, headways, vehicle requirements, grade crossing protection, and capital and operating costs. The planned GWB system runs on an exclusive dual guideway in the rail right-of-way, and the alternative LRT system operates on the existing rails with new bridges and track as needed for a dual guideway system. The analysis compares the two options for mode splits between 0.5% and 50%. Results show that while both options have approximately the same travel time, the GWB system costs approximately 30% less than the LRT system. The cost difference results primarily from lower GWB vehicle purchase and operating costs. The spreadsheets are available through the McTrans Center at the University of Florida, Gainesville, Florida.     

A shipbuilder's view of safety

Shipbuilders do not consider themselves leaders in furthering safety. There has been rapid growth in safety legislation but actual improvement has been modest. Casualty rates could most effectively be reduced in future by removing older ships. The responsibilities for safety in the longer term need consideration.