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191.
The slamming behaviour of a large high-speed catamaran has been investigated through the analysis of full-scale trials data. The US Navy conducted the trials in the North Sea and North Atlantic region on a 98 m wave piercer catamaran, HSV-2 Swift, designed by Revolution Design Pty Ltd and built by Incat Tasmania. For varying wave headings, vessel speeds and sea states the data records were interrogated to identify slam events. An automatic slam identification algorithm was developed, considering the measured rate of change of stress in the ship’s structure coupled with the vessel’s pitch motion. This has allowed the slam occurrence rates to be found for a range of conditions and the influence of vessel speed, wave environment and heading to be determined. The slam events have been further characterised by assessing the relative vertical velocity at impact between the vessel and the wave. Since the ship was equipped with a ride control system, its influence on the slam occurrence rates has also been assessed.  相似文献   
192.
This paper provides an analysis of the development of the liner route between the UK and Poland and the activities of the two main operators—EuroAfrica of Poland and United Baltic Corporation of London. The most significant factors driving the development of this trade are analysed using a combination of an industrial survey and government statistics for the route, before going on to examine the threat to the trade presented by the growth of the trucking mode.  相似文献   
193.
There are numerous possible advantages to be gained from the accurate prediction of future movements in the Baltic Freight Index (BFI). Because of the difficulties inherent in long-range forecasting, however, the potential for such predictions to provide insight into the future state of the physical dry bulk market is perhaps limited. The greater accuracy of short-term forecasts, on the other hand, facilitates the development of a forecasting model form is justified by the inevitably continuous nature of futures market speculation. Such a model is developed through the application of the Box—Jenkins approach to time series analysis and forecasting. The methodology is presented and the resulting model is evaluated on the basis of objective measures of predictive power and by comparison with alternative forecasting models. Finally, the applicability of the model to the practice of BIFFEX speculation is assessed by judging its performance within a simulated BIFFEX trading environment.  相似文献   
194.
Despite the importance of assessing the reliability of transport networks in general there is a paucity of suitable techniques. In part this is due to the fact that network performance depends both on the state of the infrastructure and on the behaviour of network users, where user behaviour is governed by expectations about the state of the network. An approach based on game theory is proposed whereby the performance of the network is estimated for the case where network users are extremely pessimistic about the state of the network. Where the routes are prespecified and route utilities depend only on exogenously given scenarios, the estimation problem may be formulated as a linear program. A reformulation of the problem as a non-linear program allows the impact of the degree of user pessimism on expected network utility to be studied. The problems of implementing the method for large networks with multiple origins and destinations is discussed and an algorithm is proposed.  相似文献   
195.
最近,对铁道车辆防火条例进行了大量改动。由于欧洲防火标准要统一,相比个别国家标准例如DIN5510,对防火文件和列车零部件质量做出了额外要求。  相似文献   
196.
A vehicle system dynamics model is presented that captures the essential braking and handling behavior of a passenger car and runs faster than real-time on a 1998 Pentium 233 MHz laptop computer. The simulation code was generated with the AutoSim multibody code generator and linked with C functions that communicate with braking hardware to create a real-time simulation (RTS) with hardware in the loop (HITL). Techniques are described that were used to allow the simulation program to work with HITL. The model (without controller) was also integrated with the Simulink environment to provide a design tool for control engineers.  相似文献   
197.
Shipping companies’ crucial need for cost cutting is their main motive for recruiting seafarers of various nationalities and formulating multicultural teams on board ships. This paper seeks to examine ways of dealing with cultural issues by being a socially responsible company. The main point of the research is to examine how managing multicultural crews is related to the shipping companies’ and the industry’s social responsibility. An extensive literature review on the cultural issues of maritime manpower, with a focus on the working and living conditions and the management of shipping crews, reveals important aspects of the subject. This analysis is enriched with qualitative data from an on-board case study, and from a survey among crew managers and manning agents. Results show that managing multicultural human resources in a socially responsible manner requires socially acceptable behaviour towards seagoing labour from all the industrial actors.  相似文献   
198.
This paper compares dogit and logit specifications of market share models, taking into account the possibility that conclusions might depend on transformations of the explanatory variables of these models. Parameter estimates are obtained both for a time-series urban transit mode of payment model and for a cross-sectional intercity mode choice model. It is demonstrated, using current maximum likelihood techniques extended to take multiple-order autocorrelation of the residuals into account, that the dogit specification is at least equal to, and sometimes clearly superior to, the logit specification irrespective of transformations of explanatory variables.  相似文献   
199.
This paper examines the evolution of urban transport planning since the 1960′s, identifies the key trends that have influenced such planning, describes the current state of urban transport planning, and speculates on the important characteristics that will influence urban transport planning over the next several decades. Fifteen planning conferences since 1957 are reviewed to show the changing perspectives on planning from the professional community. Ten areas are identified that will provide special challenge to future transport planners—demographic changes, the importance of economic production and market forces for transport system performance, multimodal perspectives for transport planning, adopting an operations focus, an important role for technology, developing a sense of community, laying the groundwork for pricing, integrating transport decision making with growth management, transport planning within a sustainability framework, and providing greater accountability of the decision making and planning processes.  相似文献   
200.
This paper examines where problems of shipping policy jurisdiction between international, supra-national and national levels have occurred. These range across the issues of public goods — safety, security and environment— and show up inadequacies in the current shipping policy-making processes. New frameworks — commonly termed “polycentric governance” and “multi-level governance”— sensitive to the complexities of the maritime industry and its associated political structure urgently need to be adopted. The paper is based upon research work recently carried out across the European Union supported by a number of publications and will include examples from Greece, the United Kingdom, Spain, France and also the new member states. Suggestions for improvements in policy-making structures will be made and recommendations put forward for consideration by policy-makers in the maritime sector at all jurisdictional levels  相似文献   
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