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21.
Abstract In a public opinion survey conducted in Santa Barbara county, California, respondents were interviewed regarding their feelings on coastal zone development, within a context of broader environmental and political issues. A high degree of expressed concern for the environment was found, but the data also indicate a widespread reluctance to allocate a greater share of personal income to improve environmental quality. Among the issues dealt with are citizen views on environmental problems, the effectiveness of government in the environmental field, offshore oil drilling, and coastal zone development. The results show that on each of the issues analyzed, a person's education, age, and the extent of his political participation are the major factors which determine his concern for the environment. Additional variables appear to have some significance in determining attitudes toward local environmental projects and perceptions of government. Offered are implications of the findings for the future of organized action on environmental problems. 相似文献
22.
E. Charles Fullerton 《Coastal management》2013,41(4):305-308
Abstract Under the Magnuson Fishery Conservation and Management Act of 1976, the federal government cooperates with states, the fishing industry, and public constituencies to regulate fisheries. This paper notes changes in U.S. fisheries over the last decade, remarks on the effectiveness of the Act, and makes suggestions for an improved fishery management process. 相似文献
23.
The "Stated Adaptation" survey is an interactive technique which allows us to obtain a clearer picture of the attitudes and behaviours of individuals when confronted with hypothetical situations, in particular inexperienced travel conditions. This method makes use of a simulation game whose purpose is to explore on small samples individuals' choice processes when selecting between the different transport alternatives which are available to them. This paper describes how gaming-simulation is designed, with reference to the issues tackled by two surveys which have recently been carried out in France (reactions to urban road pricing and perception of electric vehicles). It describes the benefits of this experimental approach which allows stated behaviours to be checked to a considerable degree. The limits and potential developments of this survey technique are also discussed. 相似文献
24.
Collision damage of jack-ups 总被引:1,自引:0,他引:1
North Sea collision accident records covering a period of ten years indicate that the risk of collisions involving jack-ups is not dissimilar to that for semi-submersibles or fixed jacket structures. However, jack-ups are much more flexible than jackets and have a much lower degree of redundancy. Their response to collisions and their ability to absorb impact energy is, therefore, expected to be considerably different in comparison to jackets. This paper examines available data and information regarding the capability of jack-ups to withstand collision impacts and investigates the level of local damage that can potentially be caused to jack-up legs due to accidental collisions. 相似文献
25.
Charles Taylor 《汽车与配件》2008,(46)
20世纪90年代中期,PA66气缸盖罩的研发工作重振旗鼓。正是早期PA66气缸盖罩的失败经验成就了如今PA66在该应用中的飞速发展。 相似文献
26.
27.
Charles S. Tapiero Dror Zuckerman 《Transportation Research Part B: Methodological》1979,13(3):207-216
This paper considers a vehicle dispatching problem with competition. For Poisson arrival processes, three dispatching policies are considered, (i) a C-policy, consisting in sending a vehicle as soon as it is filled to capacity C, (ii) a T-policy, assuming an infinite capacity and consisting in sending a vehicle every T periods and (iii) a (T, C)-policy consisting in sending a vehicle every T periods or whenever it is filled to capacity C, whichever comes first. Two firm models with cooperating and non-cooperating solution modes are resolved and results summarized in a table. Applications and examples are resolved for demonstration purposes. 相似文献
28.
Catherine Jeandel Diana Ruiz-Pino Elvis Gjata Alain Poisson Christian Brunet Edwige Charriaud Frank Dehairs Daniel Delille Michel Fiala Charles Fravalo Juan Carlos Miquel Young-Hyang Park Philippe Pondaven Bernard Quguiner Suzanne Razouls Bernard Shauer Paul Trguer 《Journal of Marine Systems》1998,17(1-4)
Between January 1990 and March 1995, the research project KERFIX undertook the first regular noncoastal multiyear acquisition of parameters related to the carbon cycle in the Southern Ocean at a time series station located at 50°40′ S–68°25′ E, 60 miles southwest of the Kerguelen Islands. The objectives of KERFIX are (1) to monitor the ocean/atmosphere CO2 and O2 exchanges and to understand which processes govern these exchanges (2) to observe and interpret the seasonal and interannual variability of the production, flux, decomposition and dissolution of carbon and associated elements at this location. In addition, micropaleontological studies describe the present and past flux dynamics in this oceanic area, to improve the knowledge of the transfer functions of some oceanographic proxies. This paper presents a survey of the KERFIX program: scientific objectives, organization of the field operations and some main results obtained since the beginning of KERFIX program, as well as the results of the temporal evolution of hydrological, chemical and biological parameters. 相似文献
29.
Jeries ABOU-HANNA Charles R. EVCES James L. HILL 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》1988,17(3):165-177
The highway transport of mobile homes is a matter of concern for the increasingly safety-minded driving public. The low speeds of towed vehicles necessary to maintain stability, together with the requirements for excessive lane widths due to clearance for the lateral motion, result in increased likelihood of traffic accidents, impeded traffic flow, and reduced highway capacity. A safe increase in the stable cruising speed, coupled with a decreased amplitude in the pendular motion helps alleviate all three of the aforementioned problems. Energy input at hitch point and lateral forces between the road and tires permit lateral vehicular motions, which occur above a critical speed, to increase in amplitude until possibly a limit cycle or instability is reached. One would expect that structural dynamics could have a pronounced influence on the lateral response of towed vehicles with large and relatively flexible chassis, such as mobile homes. The objective of this research is to determine the influence of chassis structural parameters on the lateral stability of towed flexible bodies during transport. The mass of the towing vehicle is assumed infinitely large, thus eliminating any dynamic interconnection between the towing and towed vehicles. The assumed modes method is used to describe the lateral deflection of the flexible towed vehicle. Results of the study of this model indicate that increase in structural rigidity of towed vehicle increases the critical towing speed whereas increase in the tire cornering coefficient reduces the safe towing speed, which is true only for this simplified model where the dynamic interaction with the towing vehicle is not included. 相似文献
30.
Charles L. Wright 《运输评论》2013,33(4):281-305
The idea of moving the capital of the country from the coast to Brazil's vast but isolated interior goes back nearly two centuries. The basic motivation was to encourage construction of a national highway system, which in turn would encourage economic development of the interior and reduce regional disparities. The construction of Brasilia was an integral part of President Kubitschek's national development programme in the late 1950s, accompanied by expansion and sophistication of the energy, steel, automotive and road building industries. By 1975, highway transport times and costs had been reduced to some 20–26% of their former levels in most regions, with the Central‐West, where Brasilia is located, being the area with the greatest cost reductions. Despite the success of this development package, Brasilia's transport system has been less successful on a local and regional basis. Most of the problems within the city proper (the Pilot Plan), are due to the excessive emphasis on facilitating car traffic to the disadvantage of buses and non‐motorized traffic, while there are no local rail services. The regional transport problem stems from the location of the satellite cities far from the Pilot Plan, forcing low‐income bus riders to spend 3–4 hours daily in transit and up to 30% of the minimum wage on the journey to work. Improvements depend on institutional and policy changes affecting locational patterns, demand peaks and modal split. 相似文献