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11.
Abstract

This paper offers a new approach to identify realistic acceptable levels of subsidy for flexible transport services (FTSs) and then proposes guidance on selection of the most appropriate vehicle types which should be offered in the design of FTS for different environments. The guidance is evidence based and has been derived from detailed analysis of the economic performance of seven FTS pilot applications plus a further five feasibility studies implemented as part of the EU FLIPPER (Flexible Transport Services and ICT platform for Eco-Mobility in urban and rural European areas) project. A major conclusion from the analysis is that the product of the demand multiplied by the average trip distance provides a very strong indicator as to the type of vehicle which should be used. It is hoped this guidance will provide a valuable aid in designing the most suitable and cost-effective FTS solutions in both urban and rural environments.  相似文献   
12.
为了获得始终如一的优质钨极气体弧焊缝,必须遵守焊接程序技术规范(WPS)上所列举的重要焊接参数,此外,焊接设备必须运作正常,焊接工具和夹具也必须工作正常,最后,焊工即焊接作业人员必须胜任特定的焊接作业,而且必须正常施焊。事实上对于手工钨极气体弧焊(GTAW)来说,焊工的人工熟练程度、手—眼协调性、自律性连同正确的焊接程序是成功的关健。图1为CTAW设备的典型配置。  相似文献   
13.
Freight forwarding fulfils the role of information processor. The past decade has seen considerable change in the information industry. Combine these two facts and we can begin to explain why freight forwarders have a vested interest in using computer based information systems to their full. Many organizations have tried, some with considerable success, but in others a lack of real commitment and professionalism has cost considerable sums. In this paper the background to the industry is reviewed together with an analysis of the reasons for the poor implementation of successful systems.  相似文献   
14.
Although a great deal is known about the distribution of homes and the distribution of workplaces in Greater London, the spatial relationship between them is less well understood. Using 1966 census data, the authors try to give a simple visual picture of this relationship, and to assess the relative travel intensities which would arise at different points in London from commuter trips, assuming straight line routing.The results show firstly that a large proportion of the population work quite close to their homes, with radial travel towards the city centre being only slightly more prominent than other directions of movement. The remainder tend to work near the city centre and to travel much longer distances. Secondly, relative to various annuli at 2 km increments centred on Charing Cross, the amounts of through traffic expressed as a proportion of the totals are roughly constant for radii between 4 and 14 km. Thirdly, people's choice of home in relation to their workplace is, on the whole, quite efficient, since it gives rise to a total amount of travel which is much closer to the theoretical minimum than it is to the amount corresponding to a random choice of homes from the available stock.  相似文献   
15.
Innovations in information technology, satellite navigation and hydrography are making it technically possible for commercial ships, run by very small crews, to be navigated in the world's seas and oceans with positional accuracies measured in tens of metres. If shipping lines do make the necessary investment in technological hardware, training, operational readjustments and data acquisition, and are also allowed to exploit the full potential of GPS, it will not be surprising if they then expect the ports to provide levels of information that allow the ships to exploit their new capabilities right up to the berth. Ports wishing to hold or improve their perceived service quality in the competitive port league will need to consider whether, and how, they can meet the shipping lines' requirements.

The introduction of strict product liability law adds a new dimension to the assessment of commercial risk in the various technological possibilities available to the ports. The possible costs involved in cases where third party data processors, software producers and electronic chart hardware manufacturers all stand between the port's data output and the user's perception and use of it, in a completely ephemeral form on a screen, need to be considered carefully. Simpler forms of data transmission, such as via traffic advice broadcast or by pilots in person may be seen as the more prudent choice in the five to ten year horizon.  相似文献   
16.
The Naval Research Laboratory (NRL), with industry and university participation, conducted an assessment of the concept of isolating certain wastes (i.e., sewage sludge, fly ash from municipal incinerators, and contaminated dredged material) on the oceans' abyssal seafloor. In this assessment the advantages, disadvantages, and economic and environmental viability of potential engineering methods for achieving abyssal waste isolation were identified and compared. This paper presents background to the Abyssal Plains Waste Isolation (APWI) Project, describes the characteristics of the waste streams and quantities potentially available for disposal via the abyssal isolation concept, summarizes regulations affecting use of the abyssal seafloor for disposal of wastes, and introduces the technical and scientific premises underlying implementation of the concept.  相似文献   
17.
This paper examines the apparent paradox involved in shipping lines responding to increasing cargo flows from Britain to mainland Europe by moving to shorter routes. Analysis shows, however, this move to be a logical and valuable defensive response by shipping lines but at a cost to the transport consumer.  相似文献   
18.
Shellfish aquaculture can result in conflicts among stakeholders who perceive impacts and tradeoffs regarding sense of place, aesthetic, recreational, economic, and ecological values. Pacific geoduck clams (Panopea generosa Gould 1850) are grown in intertidal plots using gear- and labor-intensive techniques that result in a high value export product. A confluence of issues has resulted in on-going social and legal tensions surrounding geoduck aquaculture in southern Puget Sound, Washington (WA), USA. Using interviews and document analysis, we explored stakeholder perspectives and policy issues related to geoduck aquaculture in southern Puget Sound. Twenty-three stakeholders were interviewed, including state agency employees, representatives of the aquaculture industry, nongovernmental organizations, landowners, a tribal member, and an academic. Nine state hearings board decisions on challenges to aquaculture permits were also analyzed. Stakeholders articulated a variety of perspectives regarding aesthetic, recreational, land-use, ecological, political, regulatory, and economic aspects of geoduck aquaculture activities. Hearings board cases addressed similar issues (aesthetic, ecological, and recreational), as well as challenges to restrictions on aquaculture. Potential strategies for managing this conflict include emphasizing best management practices, identifying and incorporating best available science, joint fact-finding approaches, and initiating and improving communication among all stakeholders.  相似文献   
19.
As a signatory to the Convention on Biological Diversity, Canada has committed to establishing a network of marine protected areas (MPAs) that effectively conserves at least 10% of coastal and marine areas by 2020. Research shows that the most effective MPAs are large, well enforced, no-take, and designed as part of a network. Canada's Pacific MPAs, designated site-by-site, cover approximately 3% of Canadian Pacific waters. We investigated how these MPAs could effectively contribute to Canada's national network by analyzing the implementation of management intent through the application of fisheries closures and conducting a preliminary assessment of their size and spacing relative to scientific guidelines. Fisheries closures outside of MPAs were similarly assessed. Results showed that 90% of existing MPAs were intended to exclude commercial fishing, yet only 2.5% fully or partially met this goal, therefore management intent was not achieved. Further, existing MPAs were small, 75% less than 10 km2 in size, but were reasonably spaced, from one to 50 km apart. While a suite of fisheries closures may be better suited to effectively contribute to a network than MPAs without fisheries closures, they would require permanent designations and management plans to meet network inclusion criteria.  相似文献   
20.
In most large cities traffic flow is controlled or manipulated in a number of ways. The methods used are mostly negative in the sense that they restrict the driver's choice of alternative routes rather than encourage him to use a particular one. This paper reviews some of the conventional measures and goes on to consider whether a more positive approach to route control might be justified, by inducing a more efficient or acceptable pattern of traffic movement in urban areas. The principal criteria for an efficient pattern are taken to be the total rate of expenditure of vehicle mileage and the frequency of route crossings, and an attempt is made to evaluate the potential benefits of route control in these terms. Social, technical and political considerations suggest that compulsory control will not be feasible for some time (at least, in the UK), but if the benefits to drivers as individuals can be shown to be worthwhile an advisory system might be practicable. Some possible systems are briefly outlined.The author is grateful to the City Engineer of Westminster City Council, Mr A.J. Cryer, for permission to publish this paper,which, however, does not necessarily represent the views . City Council. The author is greatly indebted to E. M. Holroyd for numerous suggestions and advice.  相似文献   
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