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271.
Abstract A survey of coastal state legislation reveals several types of statutes affecting activities occurring in coastal regions: Coastal management statutes, wetland statutes, and shoreline statutes. Each coastal state has adopted methods to delineate coastal areas or features, whether an entire coastal zone, a limited feature such as wetlands, or shorelands. Boundary delineation is done according to linear measurements, political boundaries, roads and highways, vegetation, elevation, tidal flow, and other factors. An appendix is provided containing state statutory provisions relating to boundary‐delineation techniques. 相似文献
272.
Abstract In 1967, a new road facilitated access to a number of small, impoverished, rural communities in a marshy region along Mexico's Pacific coast. One of these—the only one situated on the Pacific shore—began to be visited by an increasing stream of tourists. This article discusses the severe sociocultural problems which the initial phase of tourism development caused in Teacapán, and argues that these are part of a syndrome which is manifest in similar situations worldwide. By anticipating this syndrome before tourism development gets underway, planners and managers of coastal tourism development in Third World nations would be better prepared to mitigate most of its severe effects. 相似文献
273.
Michael Lawton 《汽车与配件》2008,(29)
德国采埃孚萨克斯(ZF Sachs)公司正在一个平稳快速的发展轨道上,双质量飞轮(DMFs)是其最具创新性的产品之一,它提高了多款车型的行驶平稳性. 相似文献
274.
Michael J. Sobey 《Maritime Policy and Management》1993,20(1):3-29
On 19 October 1989, the International Maritime Organization adopted a joint uslliberian resolution meant to advance international cooperation in maritime casualty investigations. This resolution reflected an international determination to achieve greater cooperation between different states in investigative matters, in a manner consistent with international law. This paper examines how the IMO resolution addresses some of the inherent problems in such a multi-national industry. It also examines the question of whether us lawmakers may, or should, impose stricter controls and restrictions unilaterally on foreign-flag ships which call on us ports. 相似文献
275.
The editorial opinions expressed in the news press can provide information on which issues are currently prominent concerns of the public, and on how public opinion may be aligned on those issues. A survey of all urban transportation-related editorials appearing in a sample of 155 U.S. newspapers during a period of 19 months in 1973–74 revealed that a number of issues related to transit financing, transit and highway investment, bicycles, and the transportation planning process were currently under debate in the urban press. This paper presents the survey's findings regarding the incidence and viewpoint of articles on these and other issues. Transit financing concerns clearly emerged as the most frequently discussed, and some agreement in editorial viewpoint was also found. The paper concludes with the authors' subjective observations on the scope and style of editorial discussion of urban transportation issues.This paper was prepared as background work for a recently-published essay on urban transportation problems (Kemp and Cheslow, 1976). The opinions expressed are those of the authors, and do not necessarily reflect the views of The Urban Institute or its sponsors. 相似文献
276.
Lars Finner Gero Poetsch Bernhard Sarnes Michael Kolbe 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2015,53(3):305-313
DB Systemtechnik is a high-performing, customer-driven service provider that, as well as authoritatively serving the Deutsche Bahn Group by dint of its specialist knowledge is also increasingly active on the global railway market. Development and testing of pantograph models and catenary systems have been part of the company's essential activity fields from the beginning. Therefore, an efficient and high-performing simulation tool is indispensable. That is why DB Systemtechnik spent high efforts to develop the program PrOSA in cooperation with the Heinz–Nixdorf–Institut (HNI) of the university Paderborn to simulate the interaction of pantograph and catenary. This article gives an overview of the most relevant properties of PrOSA. Furthermore, it is described how the benchmark requirements were implemented and processed. 相似文献
277.
Michael G.H. Bell Valentina Trozzi Solmaz Haji Hosseinloo Guido Gentile Achille Fonzone 《Transportation Research Part A: Policy and Practice》2012,46(5):790-800
The vehicle navigation problem studied in Bell (2009) is revisited and a time-dependent reverse Hyperstar algorithm is presented. This minimises the expected time of arrival at the destination, and all intermediate nodes, where expectation is based on a pessimistic (or risk-averse) view of unknown link delays. This may also be regarded as a hyperpath version of the Chabini and Lan (2002) algorithm, which itself is a time-dependent A* algorithm. Links are assigned undelayed travel times and maximum delays, both of which are potentially functions of the time of arrival at the respective link. Probabilities for link use are sought that minimise the driver’s maximum exposure to delay on the approach to each node, leading to the determination of a pessimistic expected time of arrival at the destination and all intermediate nodes. Since the context considered is vehicle navigation, the probability of link use measures link attractiveness, so a link with a zero probability of use is unattractive while a link with a probability of use equal to one will have no attractive alternatives. A solution algorithm is presented and proven to solve the problem provided the node potentials are feasible and a FIFO condition applies to undelayed link travel times. The paper concludes with a numerical example. 相似文献
278.
For an accurate evaluation of the increase in skin friction due to various surface topographies on ships, i.e. plate roughness, coatings, or bio fouling, both experimental measurements and a numerical evaluation of those measurements are necessary. The measurements are necessary as no other practical method exists to evaluate the skin friction coefficient on most surface topographies, and numerical evaluation is required to compute the roughness effects of varying ship types and speeds. Therefore, a method for measuring the skin friction coefficient for bio-fouled and structured surfaces at full-scale friction velocity is presented, and a validation of the design and measuring procedures is given. For the ship frictional resistance calculations, the Computational Fluid Dynamics (CFD) code ShipFlow has been modified to take the added friction into account. 相似文献
279.
刘光溪:入世谈判过程本身具有重大意义 入世谈判的过程对于中国经济的发展、中国经济体制改革的深化是一个巨大的教育过程.这次谈判不光是经济和贸易的交锋,还是两种文化、两种理念的碰撞,对中华民族价值取向、理性思维将产生深远的影响. 相似文献
280.
汽车振动性能的优化要求对悬架系统的单个零件进行分析,同时考虑它们在振动系统中的相互作用。这一工作的最大挑战在于如何建立简单有效的动力学模型,以便获得用于对零件的性能要求进行详细定义的足够数据。 相似文献