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41.
The coastal zone is attractive for human settlement because it tends to be resource rich, providing a good location to generate incomes and livelihoods. Equally, however, it is a complex and powerful natural environment, which means that the coastal zone often becomes a focus of conflict with multiple users competing for limited space and resources. Understanding the causes of, and determining solutions to, the ensuing problems requires inputs from a range of analyses across sectors and disciplines. However, different disciplinary and sectoral approaches frequently use different investigative methods, language, and means of presenting results. This article presents a framework that has been developed in collaboration with Indian institutions over the past three years in an effort to address some of these fundamental problems of analysis and translation into policy action. Key components addressed by the framework are strengthening the capacity to practice, knowing how to proceed and how to find out what needs to be known using experience-based problem solving.  相似文献   
42.

Traveller information provision has become a key government priority in the UK following the publication of its Transport White Paper in July 1998. Developments are already underway for the integration of information systems across different public transport modes and between public transport information systems covering different regions. The Highways Agency (which is responsible for managing the strategic road network in the UK) is also advancing in its development of information databases and systems for the motorist. This paper considers the prospect of providing travellers with multimodal information with integration of driver information with public transport information. If such integration can be achieved then travellers, and in particular drivers, have the prospect of being presented with comparable information on travel options across modes. An integrated information service has a great potential to inform and influence travel choices. The paper considers the issue of travel choices and the role that information can play particularly in the context of mode choice. The political (UK) and technological climate for information provision is outlined. The paper identifies issues that will need to be addressed to identify the requirements from, and potential benefits of, integrated information, and the obstacles and challenges likely to be faced in moving towards it. Driver reactions, in particular, to the prospect of integrated information provision are fundamental to the assessment of its potential importance and value.  相似文献   
43.
Abstract

Growth in the number of cottager, or lake property owner, associations in Ontario has been rapid. Cottager associations attempt to address directly, and influence government decision‐making on, issues affecting shoreline management and the recreational experience of cottagers. However, associations infrequently resolve these issues to their satisfaction. A questionnaire and case study show that the nature of the issue, human and financial resources available to the association, and the nature of the decision‐making process affect the extent to which associations influence outcomes. Unreceptiveness of government officials to association participation in decision‐making and confused agency jurisdictions over shoreline resources appear to inhibit association effectiveness. Concerns about the status of shoreline management in Ontario and public participation in decision‐making are raised.  相似文献   
44.
There have been many efforts to develop a logistics information system in the Korean logistics industry. In spite of these efforts, there are many points which need improvement in the Logistics Information System, of which function is the electronic data communication without added value. This paper aims to describe some of the main problems and the successful factors which are being found in the evolution of the present EDI systems for clearing import/export container cargoes, with special reference to Singapore, Korea, and Japan. Following this, leaving legal issues aside, to suggest workable guidelines for designing a new efficient EDI system for container cargo logistics. As a result of the review, the following successful factors are drawn: (a) the planning, requirement analysis and design of EDI are critical, as it provides a framework for its implementation; (b) as the data of customs clearance are an integral part of a logistics EDI system, the inclusion of customs in the system design is essential; (c) the sharing system of cargo data as the framework of the logistics EDI is efficient for data interchange; (d) the EDI software for the user has been developed and provided by an EDI network operating company; and (e) to facilitate communication between trading partners and the transport sector, it is necessary to adopt a global message standard, such as EDIFACT.  相似文献   
45.
By incorporating port competition into a third-market model consisting of two exporting firms and one importing country, we demonstrate the endogenous choice of port structures (i.e. privatization or public ownership) under either Bertrand or Cournot competition. In contrast to previous studies on port competition, we analyze the port strategy in view of all trading countries (i.e. importing country and exporting countries). We find that regardless of transport cost, the port ownership strategy alters according to exporting firm’s competition mode. Under Bertrand competition, the choice of port ownership structure depends on the degree of imperfect substitutability. However, under Cournot competition, all trading countries choose same ownership structures of each port. By comparing equilibrium of each competition mode, we show that welfare of exporting country under Cournot competition is higher than under Bertrand competition if goods are sufficiently substitutes. In contrast, importing country prefers Bertrand competition to Cournot competition when the competitive pressure is sufficiently high.  相似文献   
46.
Damper Models for Heavy Vehicle Ride Dynamics   总被引:18,自引:0,他引:18  
A laboratory rig for testing hydraulic dampers using the 'hardware-in-the-loop' method is described, and the accuracy of the test method is investigated. A mathematical model of a hydraulic shock absorber is then developed. The model is suitable for vehicle simulations and has seven parameters which can be determined by simple dynamic measurements on a test damper. The shock absorber model is validated under realistic operating conditions using the test rig, and the relative importance of various features of the model on the accuracy of vehicle simulations is investigated.  相似文献   
47.
In previous publications the author has described a so-called first-order theory for the motion of a railway vehicle wheelset on a tangent track. In the present report the geometrical aspect of this theory is further evaluated and a method for solving the constraint equations between the coordinates of the wheelset is indicated.  相似文献   
48.
This paper presents vibration control of a tracked vehicle installed with electro-rheological suspension units (ERSU). As a first step, an in-arm type ERSU is designed, and its spring and damping characteristics are evaluated with respect to the intensity of electric fields. Subsequently, a 16 degree-of-freedom model for a tracked vehicle equipped with the proposed ERSU is established followed by the formulation of a neuro-fuzzy controller. This controller takes account for both ride quality and steering stability by adopting a weighting parameter between two performance requirements. The parameter is appropriately determined by employing a fuzzy algorithm associated with two fuzzy variables: the vertical speed of the body and the rotational angular speed of the wheel. Control performances to isolate unwanted vibration from bump and random road excitations are evaluated through computer simulations. In addition, maximum speed of the vehicle with 6 Watt power absorption is investigated with respect to the road roughness.  相似文献   
49.
应用有限元法研究车架结构的耐撞性   总被引:1,自引:0,他引:1  
王春雨  李一兵 《汽车工程》1997,19(6):336-341
本文应用有限地对车辆正面碰撞过程中车架结构的大变形过程进行了计算机模拟。文中介绍了非线性有限元分析的基本方程,运用微机版DYNA3D软件,在合理简化的基础上,建立了车呆结构的有限元模型,通过计算机模拟,预测了车辆正碰过程中车架的变形位置和变形形式。针对存在的问题,对车架结构进行了改进设计。实车碰撞试验表明:改进后,车架结构的耐撞性有明显提高。  相似文献   
50.
Semi-active Damping with an Electromagnetic Force Generator   总被引:1,自引:0,他引:1  
The main shortcoming of vehicle suspension systems is the amplification of input vibrations at the resonant frequency. A non-amplifying suspension system with a semi-active damping is being developed. The use of an electronically controlled rotational damper has been studied theoretically. A new sprung seat is being designed for the improvement of the working conditions for drivers of road and terrain vehicles.  相似文献   
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