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921.
电力工业循环经济发展模式及主要措施探讨   总被引:3,自引:0,他引:3  
介绍了我国电力工业的发展现状,归纳总结了存在的问题。论述了电力工业发展循环经济的必要性,提出了电力工业发展循环经济的模式和主要措施。  相似文献   
922.
Land resource sustainability for urban development characterizes the problem of decision-making with multiplicity and uncertainty. A decision support system prototype aids in the assessment of incremental land development plan proposals put forth within the long-term community priority of a sustainable growth. Facilitating this assessment is the analytic hierarchy process (AHP), a multicriteria evaluation and decision support system. The decision support system incorporates multiple sustainability criteria, weighted strategically responsive to local public policy priorities and community–specific situations and values, while gauging and directing desirable future courses of development. Furthermore, the decision support system uses a GIS, which facilitates an assessment of urban form with multiple indicators of sustainability as spatial criteria thematically. The resultant land-use sustainability scores indicate, on the ratio-scale of AHP, whether or not a desirable urban form is likely in the long run, and if so, to what degree. The two alternative modes of synthesis in AHP—ideal and distributive—provide assessments of a land development plan incrementally (short-term) and city-wide pattern comprehensively (long-term), respectively. Thus, the spatial decision support system facilitates proactive and collective public policy determination of land resource for future sustainable urban development.  相似文献   
923.
重庆新型工业化的必由之路--生态工业园区   总被引:1,自引:0,他引:1  
随着全球保护环境、实现可持续发展的呼声日益高涨,由此出现了一种新型的工业组织形态--生态工业园区,它通过一个区域内的物流和能源的正确设计模拟自然生态系统,形成企业间共生网络,达到减少废物,实现园区污染"零排放"的目标,从而成为各国可持续发展的主要模式之一.目前重庆地区已经规划建立了40多个特色工业园区,但没有一个是真正意义上的生态工业园区,因此结合相关构建理论,在重庆建立生态工业园区很有必要.  相似文献   
924.
以人权原则以及现代工业的理念 ,从现代安全管理体系和方法的新要求入手 ,站在长久安全和可持续发展战略的高度 ,探求新的安全管理理念和模式 ;进一步研讨了区域战略安全管理模式 ,并归纳出其类型与层次 ;概述了国内外安全管理模式的发展历程 ,对我国战略安全管理的现状和对新模式的探索过程进行了分析 ,归纳出国内外战略安全管理新理念构架 ;重点阐述了HSE(健康、安全、环境 ) ,QHSE(质量、健康、安全、环境 ) ,OHS(职业健康安全 )管理体系战略、安全文化战略以及美国和欧共体战略安全管理等先进理念 ;最后提出了闭环控制的滚动式战略安全管理技术构思和战略安全管理的国内外发展趋势。区域战略安全管理模式的应用与发展将使现代安全管理提高到一个新的高度。  相似文献   
925.
ABSTRACT: The U.S. Geological Survey (USGS) is assessing the ground-water resources of the carbonate bedrock aquifers in Indiana and Ohio as part of their Regional Aquifer Systems Analysis program. Part of this assessment includes the determination of unknown aspects of the hydraulic characteristics, boundaries, and flow paths of the carbonate aquifer. To accomplish this, the USGS drilled three wells through the carbonate aquifer near the Kankakee River in northwestern Indiana. Geophysical logs were used to help determine depths and thicknesses for testing and to help describe geology at the three wells. Packer tests were used to determine direction of ground-water flow and to provide data for an analysis of the distribution of transmissivity in the carbonate aquifer. Transmissivity of the carbonates is associated with two physical characteristics of the rocks: fractures and interconnected porosity. Almost all of the transmissivity is derived from horizontal fracturing; however, only a few of the fractures present in the carbonate are transmissive. Some transmissivity is associated with a zone of fossiliferous, vuggy dolomite, which yields water from the rock matrix. Most of the transmissivity is associated with large fractures and solution crevices in the upper 30 feet of the bedrock; less transmissivity is associated with the deeper vuggy reef material, even where extensively fractured. Transmissivity of individual fractures and fossiliferous zones ranges from 300 to 27,000 feet squared per day. The aquifer bottom is defined by a lack of transmissive fractures and an increased shale content near the contact of the Silurian and Ordovician sections. Water-level data from the three wells indicate that flow is horizontal at well site 1 north of the Kankakee River, upward at well site 2 near the river, and downward at well site 3 south of the river. Most of the flow occurs in the upper part of the carbonate bedrock where fracturing and solution-enlarged crevices are most developed. Water levels indicate the the Kankakee River is a hydrologic boundary for the regional carbonate bedrock aquifer.  相似文献   
926.
Whether animals are active at night or during the day has profound consequences for many aspects of their behavioral ecology. Because of ecological and physiological trade-offs, most animals, including primates, are either strictly nocturnal or diurnal. However, a few primate species exhibit cathemeral activity, i.e., their activity is irregularly distributed throughout the 24-h cycle. Details and determinants of this unusual activity pattern are poorly understood because long-term 24-h observations are not feasible in the field. We therefore used small data loggers to record the activity of cathemeral redfronted lemurs (Eulemur fulvus rufus) from several neighboring groups quantitatively and continuously over a complete annual cycle in order to evaluate various proposed proximate and ultimate determinants of cathemeral activity. Activity data were examined for variation as a function of ambient temperature, time of day, lunar phase, and season. We found that cathemeral activity occurred year-round and that, on average, 3.5 times more activity occurred during the day. Total and diurnal activity increased during the long days of the austral summer. Nocturnal activity increased during the longer nights of the cool dry season. Irrespective of season, lunar phase had a significant effect on the distribution of activity across the 24-h cycle, with most nocturnal activity recorded during parts of the night with greatest brightness. These data indicate that light availability is the primary proximate determinant for the patterning of cathemeral activity. Several lines of evidence suggest that cathemerality in lemurs has evolved from nocturnal ancestors and that it represents a transitory state on the way to the diurnal niche.Communicated by F. Trillmich  相似文献   
927.
邓超  李培根 《环境技术》2002,20(4):45-49
当前经济研究中对环境问题越来越重视,已经有多种不同方法可以用来研究材料和物质流在经济中的运转,物流分析模型(SFA)就是其中一种。本文将SFA应用于一个单一的,假设的污染问题中,这样以实践的方式来评价模型的结果。结果显示,SFA模型能够发现潜在的或预料不到的物质流和排放物,并能发现在将来某一时候会引起经济和环境问题的积累。  相似文献   
928.
Soil loss and surface runoff patterns were studied in erosion plots developed on manmade steep slopes (60 percent) over three years (1997–2000) in which rainfall ranged from 1338.4 to 1429.2 mm/year. Surface runoff and soil loss was examined under three different rainfall intensity classes. Runoff was mainly controlled by the rainfall distribution pattern on the seasonal scale. The soil loss was influenced by runoff during the first year. Both soil loss and runoff were reduced due to bioengineering measures in the first year irrespective of species planted. In the third year, combined effects of growth of grasses on protected plots, soil compaction and sediment exhaustion was noticed on runoff and soil loss. This was reflected by reduction in the runoff and soil loss from untreated and treated plots. In the high intensity class, reduction in runoff in treated plots was about 50 percent in three years and reduction in soil loss ranged between 94–95 percent in all plots. Physical treatment with brushwood structures was more efficient in erosion control in the low intensity class.  相似文献   
929.
ABSTRACT: To provide a basis for regional hydroclimatic forecasting, New England (NE) precipitation and streamflow are compared with indices for the El Niño/Southern Oscillation, the Pacific North American (PNA) pattern, and the North Atlantic Oscillation (NAO). Significant positive correlations are found between the NAO index and monthly streamflow at western inland locations, with the strongest seasonal correlations occurring in winter. Smoothed records for the winter NAO and winter streamflow are highly correlated at some sites, suggesting that interrelationships are most significant in the low frequency spectrum. However, correlations between the NAO and precipitation are not significant, so further examination of other factors is needed to explain the relationship between the NAO and streamflow. NAO related regional air temperature, sea surface temperature (SST), storm tracking, and snowfall variability are possible mechanisms for the observed teleconnection. Exceptionally cool regional air temperatures, and SSTs, and unique regional storm track patterns characterized NE's climate during the famous 1960s drought, suggesting that concurrent (persistent) negative NAO conditions may have contributed to the severity of that event. Monthly and winter averaged regional streamflow variability are also significantly correlated with the PNA index. This, along with results from previous studies, suggests that tropospheric wave character and associated North Pacific SST anomalies are also related to NE regional drought conditions.  相似文献   
930.
在后混合磨料射流或准直管磨料射流中,为使水射流的动量能够充分传递给磨料,往往需要用准直管同轴套住水射流,以避免因流的侵入。准直管水射流流动特性是影响准直管磨料射流混合和加速磨料效果的主要因素,利用可视化实验和动量守恒原理对准直管水射流的流动特性进行了研究,其结果表明:准直管水射流流动特性状态随压力变化而变化;高压准直管水射流具有扩散流动段、平行流动段和回气流动段;高压准直管水射流的打击力具有沿程损失和出口损失。此外,还推导出了高压准直管水射流打击力的计算公式。  相似文献   
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