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51.
本文从浮放物体的基本运动方程出发,导出了浮放物体受震振动的运动参数表达式,它是用仿真技术研究浮放物体地震运动的基本公式.  相似文献   
52.
This article analyzes water quality on a global scale. An overview of the global water supply and demand situation is presented first, including regional and country information, as well as data on selected water use patterns. The focus then shifts to a discussion of water pollution, its various causes, impact, and remedies, with emphasis on legal and administrative solutions. Water pollution control expenditures and the resultant achievements are dealt with in the final third of the article, with projections to 1995. A wide variety of published sources was dovetailed to obtain a composite picture and most likely scenario; this was supplemented with primary interviews by the author conducted in North America, Western and Eastern Europe, and Oceania at the start of the 1980s.  相似文献   
53.
The siting of facilities with undesirable environmental characteristics often leads to public conflict. Efforts to resolve the conflict and make siting decisions frequently exacerbate the problem. Environmental mediation, the process of negotiating an agreeable settlement, is an accepted approach to resolving conflict. This paper explores the use of incentive systems as a means of achieving equity in environmental mediation. Obnoxious and noxious characteristics of facilities are discussed as the basis of conflicts. Four types of incentives—mitigation, compensation, reward, and participation—are discussed. The paper concludes with a discussion of the utility and application of incentives for solving environmental conflicts.  相似文献   
54.
元代1264年定都燕京后,为加强政治统治,在中原先进的农耕经济影响下,改变过去“逐水草而居”游牧经济的生产方式,在积极保护动、植物资源和合理开发利用土地、水资源等方面,采取了一些恢复和发展农业生产的举措。剖璞见玉,对今仍有史鉴作用。  相似文献   
55.
The production of large quantities of wastes globally has created a commercial activity involving the transfrontier shipments of hazardous wastes, intended to be managed at economically attractive waste-handling facilities located elsewhere. In fact, huge quantities of hazardous wastes apparently travel the world in search of “acceptable” waste management facilities. For instance, within the industrialized countries alone, millions of tonnes of potentially hazardous waste cross national frontiers each year on their way for recycling or to treatment, storage, and disposal facilities (TSDFs) because there is no local disposal capacity for these wastes, or because legal disposal or reuse in a foreign country may be more environmentally sound, or managing the wastes in the foreign country may be less expensive than at home. The cross-boundary traffic in hazardous wastes has lately been under close public scrutiny, however, resulting in the accession of several international agreements and laws to regulate such activities. This paper discusses and analyzes the most significant control measures and major agreements in this new commercial activity involving hazardous wastes. In particular, the discussion recognizes the difficulties with trying to implement the relevant international agreements among countries of vastly different socioeconomic backgrounds. Nonetheless, it is also noted that global environmental agreements will generally be a necessary component of ensuring adequate environmental protection for the world community—and thus a need for the careful implementation of such agreements and regulations.  相似文献   
56.
ABSTRACT: The period of time from identification of a possibly desirable inland waterway transportation project to its actual implementation has been observed to be inordinately long. It is Hypothesized that at Least one cause of delays in project approval and implementation is a analytical credibility associated with project feasibility analysis conducted by the U.S. Army Corps of Engineers. This paper examines this hypothesis in terms of the proposal to construct a new, expanded lock at the Bonneville Dam on the Columbia River. The principle finding is that the analysis conducted by the Corps is conceptually flawed, methodologically questionable, internally inconsistant, and inappropriately narrow in scope.  相似文献   
57.
ABSTRACT: Net precipitation under old growth Douglas fir forest in the Bull Run Municipal Watershed (Portland, Oregon) totaled 1739 mm during a 4Cbweek period, 387 mm more than in adjacent clearcut areas. Expressing data on a full water year basis and adjusting gross precipitation for losses due to rainfall interception suggest fog drip could have added 882 mm (35 in) of water to total precipitation during a year when precipitation measured 2160 mm in a rain gage in a nearby clearing. Standard rain gages installed in open areas where fog is common may be collecting up to 30 percent less precipitation than would be collected in the forest. Long term forest management (Le., timber harvest) in the watershed could reduce annual water yield and, more importantly, summer stream flow by reducing fog drip.  相似文献   
58.
ABSTRACT: The cost of sanitary facilities is a major cost item in recreation areas at water resources projects. Often planners wish to analyze the tradeoffs in providing different levels of service at these areas. Cost functions are presented in this paper to enable the planner to make quick comparisons between different types of buildings, sizes, exterior treatments, and number of fixtures.  相似文献   
59.
邯郸市沁河水污染治理方案   总被引:1,自引:0,他引:1  
本文对邯郸市沁河水污染现状进行了调查分析,总结了城市内河治理经验,通过方案比较,推荐“清淤,护坡,建坝,分质截污,邯钢废水混凝沉淀处理”为沁河治理方案。  相似文献   
60.
根际土壤微生物是植物修复及其强化修复技术的重要组成部分,了解根际土壤微生物生态效应有助于深入探索修复机制,从而进一步提高修复效率.微生物生态效应反映土壤生态变化,对于有效评估强化调控生态风险具有重要意义.在总结污染土壤植物修复根际微生物生态效应研究的基础上,综述强化调控措施与根际土壤微生物可能存在的相互影响,并分析利用微生物分子生态学技术评估强化调控措施施用风险的可行性.  相似文献   
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