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721.
722.
David H. Moreby 《Maritime Policy and Management》1990,17(3):199-205
The globalization of shipping means that the industry needs cosmopolitan managers who can negotiate with—and manage—people of different cultures. The causes and consequences of cultural differences are explained in the paper with particular reference to power differentials and rule orientation. The dangers of stereotypes are high-lighted. Communication problems are discussed in the context of transmitting values. 相似文献
723.
T. R. O'Brien 《Maritime Policy and Management》1980,7(2):127-132
The manner in which CAFs have been applied to cargo carried by lines appears to be both arbitrary and secretive. This note intends to give some clarification as to how the CAF is calculated and the manner in which it is applied.
The operation of the two methods, i.e. the monthly review and the radical review, is merely a device which enables conferences to adjust effective charges so as to leave lines without a loss in real revenue, although minor losses and gains will be inevitable as the operation of the CAFs take time to be implemented.
Finally it is hoped to point out the volatilc nature of CAF changes impinges upon the uncertainty of lines' costs. 相似文献
The operation of the two methods, i.e. the monthly review and the radical review, is merely a device which enables conferences to adjust effective charges so as to leave lines without a loss in real revenue, although minor losses and gains will be inevitable as the operation of the CAFs take time to be implemented.
Finally it is hoped to point out the volatilc nature of CAF changes impinges upon the uncertainty of lines' costs. 相似文献
724.
725.
A statistical approach is shown to be adaptable to the N-city traveling salesman problem by considering route distances to be random variables which are continuous and normally distributed. A solution to the shortest route distance and path can be approximated by utilizing a Monte Carlo simulation to obtain a representative sample of possible journeys. The approach involves recursive statistical inference which is used to select next-city visits leading to the most probable minimum route path. A statistical selection of the minimum route path is computationally efficient and computer run time increases in proportion to the square of the number of cities as opposed to an (N - 1)! increase for a deterministic approach. The accuracy of the statistical approach is directly proportional to the number of Monte Carlo simulations. 相似文献
726.
727.
Sven T. H. Jansen Peter W. A. Zegelaar Hans B. Pacejka 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》1999,32(2):249-261
For efficient analysis it is important to choose the proper model that fits the problem that needs to be solved. This paper discusses three pragmatic simulation models for longitudinal behaviour of a passenger car tyre (Steady State, Transient and Rigid Ring) that may be used in e.g. an ABS simulation. The characteristics of the simulation models are evaluated using some simple simulations. Simulations with a quarter vehicle model that includes load transfer effects are carried out to determine the deviation in results between the mentioned tyre models for an ABS application. The results show that the Steady State model may only be used below 10 Hz and that the Transient model is valid up to about 30 Hz. The results from the ABS simulation with the Rigid Ring model are most reliable and are clearly different from the Steady State and Transient model, which indicates that ABS simulations should be carried out with the Rigid Ring model. Additionally it is demonstrated that for tyre behaviour on uneven roads the influence of the tyre belt cannot be neglected. 相似文献
728.
TRESIS: A transportation,land use and environmental strategy impact simulator for urban areas 总被引:1,自引:0,他引:1
The Institute of Transport Studies has developed a Transportation and Environment Strategy Impact Simulator (TRESIS) as a decision support system to assist planners to predict the impact of transport strategies and to make recommendations based on those predictions. A key focus of the simulator is the richness of policy instruments such as new public transport, new toll roads, congestion pricing, gas guzzler taxes, changing residential densities, introducing designated bus lanes, implementing fare changes, altering parking policy, introducing more flexible work practices, and the introduction of more fuel efficient vehicles. The appropriateness of mixtures of policy instruments is gauged in terms of a series of performance indicators such as impacts on greenhouse gas emissions, accessibility, equity, air quality and household consumer surplus. In this paper we introduce TRESIS to the research community, focussing on the structure of the system and the diversity of applications. Applications are presented to illustrate the diversity and richness of TRESIS as a policy advisory tool. 相似文献
729.
Ernesto García Vadillo José A. Tárrago Gorka Garate Zubiaurre Carlos Angulo Duque 孙晓静聂志理译 《都市快轨交通》2010,23(2):13-17
主要研究轨枕间距对钢轨波磨发展的影响。研究小半径曲线内轨的小矢跨比波磨。这些出现问题的曲线段属于西班牙毕尔巴鄂区域的地铁轨道,铺设着混凝土道床和两层STEDEF型支承垫层。当初始轨枕间距为1000mm时,仅有92万组轮对通过后所测得的波磨深度峰-峰值已经达到0.42mm。随后更换产生波磨的钢轨,比较列车通过时轨枕上方和轨间中部的内轨垂向、横向加速度。当轨枕间距为1000mm时,轨间中部出现频率为204和244Hz的强烈响应,在轨枕上方却未出现。在相邻轨枕中间铺设一个轨枕,使轨枕间距变为500mm,钢轨波磨停止发展。该结论是根据2年的观测结果得到的。 相似文献
730.
Some vehicle components are developed by setting target weights to the gram level at their design stages to accomplish a lightweight design. Recently, there have been many studies that have focused on lightweight design through the use of ultra-high-strength steels. However, a lightweight design can face many challenges if the reliability of the analysis is not also secured at the design stage. Such challenges include difficulties in coupled analyses when the file formats are different among PAM-STAMP, ABAQUS, and NASTRAN. In this study, we developed a mapping interface that enables mapping between the file formats of various software programs. Buckling analysis was coupled to the forming analysis, in which pre-strain test data were applied in considering the material’s strain hardening, to evaluate the rigidity of the front lower control arm that controls the wheels and transfers loads. The influence of forming effects on endurance was evaluated, and residual stresses around the weld zone were calculated. A comparison of experimental and analytical results indicated that the proposed analysis was highly reliable. 相似文献