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861.
The analysis tests the utility of a simple regression approach in postdictively explaining transport development in West Malaysia from 1887 to 1968. The growth of the network is modelled as a process of contagious diffusion where transport densities of adjacent cells are used as predictor variables on a lagged basis. The partial regression coefficients provide measures of network orientation over time. The results demonstrate the importance of the contagion process in transport forecasting and provide equivalent levels of explanation when compared with a model which utilizes modernization indexes as predictor weights.I am grateful to Peter Gould for his advice and suggestions in the early stages of the research and for the comments of Peter Haggett, Mark Monmonier and J. Barry Riddell, all of whom read drafts of the paper. I also wish to acknowledge the financial support provided by a University of Vermont Faculty Fellowship. 相似文献
862.
863.
The success of any enterprise, in a market-oriented economy, depends upon it's quality. This paper describes the results of a survey of commuters on the quality of services and their relative weights, and of the attributes that determine the service level of bus transport undertakings. The model uses the theory of fuzzy sets to process the information obtained. A composite index, called level-of-public transport-service (LOPTS), is defined and used to measure the service qualities. This approach is presented with guidelines for rating the quality of services, fuzzy-set representations of the linguistic grades, definition of LOPTS and its use in a public transport quality data base. An example is presents how the approach can be employed to analyse data bases generated from a quality survey. This approach is compared with the numerical rating approach with single number representation. 相似文献
864.
R. M. Webb
R. B. Corr
《Marine Structures》1991,4(6):533-569The environmental and structural monitoring system on Magnus tower was designed making use of experience from previous monitoring systems on West Sole, Forties and Buchan. The paper describes the measuring systems adopted together with their calibration procedures and independent checks.
The major results in terms of environmental conditions and platform response are discussed. They are compared with the Forties results and standard design procedures. Deterministic and spectral extreme conditions are considered. Where applicable, comparisons are made with other published results.
Finally, the principal conclusions of the measurement programme are presented and discussed. These refer particularly to structural dynamics, coefficients for the Morison equation and appropriate methods of application of wave loading to a deep water structure. 相似文献
865.
J. A. L pez A. Miravete J. R. S nchez 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》1987,16(2):91-105
In the present article, a mathematical model of the car-caravan combination has been constructed. In simulating the transmission of forces in the articulation of the joint, special attention has been focussed on two types of action in the braking system of the caravan: the conventional braking through overrun and a prototype with hydraulic action. The model of the articulation has been compared with tests carried out on a real vehicle. This model has been constructed by means of a computer programme with different braking maneuvers with the view to analyse the influence of one system or the other on the general behaviour of the vehicle. 相似文献
866.
867.
德国MTU公司生产的396系列柴油机广泛应用于铁路电传动和液力传动内燃机车,内燃动车以及用于列车供电的发电车,至今已售出1600多台,其中累计工作时间最长的已超过90000h。文中介绍了该系列柴油机的主要设计特点以及最近所作的技术改进,列举了若干该系列发动机的典型应用实例。 相似文献
868.
R. Ranganathan Graduate Student S. Rakheja Research Associate Professor S. Sankar Professor Director 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》1990,19(4):177-200
The influence of the lateral load shift on the dynamic response characteristics of an articulated tank vehicle is investigated assuming inviscid fluid flow conditions. A quasi-dynamic roll plane model of a partially filled cleanbore tank of circular cross-section is developed and integrated to a three-dimensional model of the articulated vehicle, assuming constant forward speed. The destabilizing effects of liquid load shift are studied by comparing the directional dynamics of the partially filled tank vehicle to that of an equivalent rigid cargo vehicle subject to steady steer input. Dynamic response characteristics demonstrate that the stability of a partially filled tank vehicle is adversely affected by the Liquid load shift The distribution of cornering forces caused by the liquid load shift yield considerable deviation of the path followed by the liquid tank vehicle. The influence of the vehicle speed on the dynamics of the liquid tank vehicle is also investigated for variations in the fill levels and fluid density. 相似文献
869.
870.