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211.
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   
212.
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   
213.
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   
214.
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   
215.
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   
216.
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   
217.
The torsional vibration generated during clutch engagement directly affects the shifting quality of automatic transmissions, where the noise source stems from both the clutch and the gear set. To predict the dynamical response and driveline oscillation, a comprehensive mathematical model of the vehicle powertrain equipped with automatic transmission is developed with consideration of nonlinearities in the clutch and the planetary gear set. For the clutch, the dynamics of stickslip is described for the transition between the slipping to locked states. The gear backlash model is used to analyze the rattle noise of the planetary gear set. Based on extensive powertrain simulations for the clutch engagement process, the magnitude of vibration propagation in the driveline are predicted to identify the primary factors of noise generation.  相似文献   
218.
We examine whether specific types of people are more sensitive to the built environment when making a decision to walk or engage in other physical activity. Over 700 participants from 36 environmentally diverse, but equivalent-sized neighborhoods or focus areas responded to a survey, kept a travel diary, and wore an accelerometer for seven days. Subgroups defined by demographic and socioeconomic variables, as well as self reported health and weight status demonstrate that most subgroups of people walk more for transportation in high density areas. However, only the less healthy walked more overall in high density areas after controlling for sociodemographic characteristics and physical activity was remarkably similar among the groups and across different kinds of environments. While environmental interventions may not increase physical activity population wide, some populations – including some for whom interventions may be important such as the less healthy and the unemployed or retired – are more affected by these neighborhood environmental characteristics.  相似文献   
219.
The paper focuses on the role that can be played by urban consolidation centres (UCCs) in reducing freight traffic and its environmental impacts in towns and cities. It is based on the before and after evaluation of a trial led by a major stationery and office supplies company in which urban freight deliveries in central London made from a depot in the suburbs using diesel vehicles were replaced with the use of an urban micro-consolidation centre located in the delivery area together with the use of electrically-assisted cargo tricycles and electric vans. The results show that the total distance travelled and the CO2eq emissions per parcel delivered fell by 20% and 54% respectively as a result of this delivery system. However, the evaluation has also indicated that the distance travelled per parcel rose substantially in the City of London delivery area as a result of the electric vehicles having far smaller load limits in both weight and volume compared with diesel vans. But, at the same time, the trial system was able to virtually eliminate CO2eq emissions per parcel delivered in the City of London. The trial proved successful from the company's perspective in transport, environmental and financial terms. The company therefore decided to continue the operation beyond the end of the trial with it being officially launched during 2010.  相似文献   
220.
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