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171.
Traditionally, liner markets have been seen as dominated by conferences on the seller side, facing small, unorganized shippers onn the buyers' side. This perceived asymmetry has greatly influenced conference legislation in North America (and more recently in the E.U.) and it has been deemed essential that government should regulate conference activities in order to curb any abuse of 'conference power'. In this view, shipowners and shippers are adversaries engaged in a zero-sum battle over transport costs rather than potential or actual partners in global distribution systems. This paper suggests that in today's global markets much can be achieved by cooperationn in the development of logistics systems and that shipowners and shippers may have much to gain from such cooperative alliances. A survey of shippers' councils in 1991-1992 demonstrates the diversity and increasing sophistication of many national shippers' councils, which devote themselves to the task of improving markets through education and the legislative process. The situation in the U.S.A. is different: for legal reasons, conventional shippers' councils do not exist. Instead, 'shippers' associations' play a commercial role in liner markets. It is suggested that European style shippers' councils can and should play an important role in the development and formulation of policies for internatinal liner markets. Such participation requires a cooperative industry environment quite different from the traditional adversarial approach, which is ill suited to global trade and logistics alliances.  相似文献   
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Weid.  K 张兆奎 《汽车工程》1993,15(6):335-344
本文以联邦德国农业及经济状况为出发点,介绍了利用生物制品,主要是粮食,油料等农产品转化为发动机燃料的研究工作情况,并重点介绍了用菜籽油和酒精的试验研究情况。  相似文献   
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Due to the capital-intensive nature of the modern shipping industry, loan finance plays a major role in vessel-acquisition cost. In this paper, J. B. Yolland discusses government-guaranteed finance, ancillary and commercial new building finance and finance for second-hand tonnage. He also examines a new source of funding found in the Euro-market.  相似文献   
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The United States meets the world shipping crisis of the 1970s with a high-cost merchant fleet and a national maritime policy which needs clearer articulation. This paper examines the objectives, rationale and methods of implementation of the Us maritime programme with attention, finally, to the question of governmental reorganization.  相似文献   
179.
This paper presents a novel user-equilibrium (UE) traffic assignment algorithm, which under conventional assumptions, promises to compute UE arc flows to acceptable precision, regardless of the network’s topology, size or congestion:
• The algorithm takes the simple approach of shifting flow from a costliest path to a cheapest path until the costs of all used paths are within a given of the cheapest.
• Because of being path-based, it avoids tailing.
• In spite of being path-based, it neither stores nor enumerates paths.
• These efficiencies derive from decomposing the problem into a sequence of easy single-origin problems on acyclic sub-networks.
Solutions to this sequence of sub-network flows converge rapidly to a sharp practical estimate of UE arc flows—as is amply demonstrated by tests using the Chicago region’s 40,000-arc network model.  相似文献   
180.
A particular parameter estimability problem in the multinomial probit model is considered. Making use of a model discussed in the literature, some problems with the usual method of specification are discussed. Some general comments are made on the problem of selecting a normalisation when using the multinomial probit model.  相似文献   
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