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141.
142.
Thomas M. Bonnicksen 《Environmental management》1981,5(6):521-529
A cross-impact simulation computer language, UW-KSIM, is presented as a potentially useful technique for assessing the consequences of resource policies. Cross-impact simulation is used to estimate trends in a set of variables that result from interactions produced from hypothesized relationships among the members of the set. This technique is illustrated with an example that simulates the likely impacts of a 20-year rotation burn policy in southern California's brushland watersheds and that compares the results to a simulated representation of the observed effects of the fire-exclusion policy. Simulated losses under the fire-exclusion policy were up to 300% higher than those produced by the rotation burn policy. Similarly, the simulated average area burned per year was reduced from 5.6% of the study area under the fire-exclusion policy to 2% of the study area under the rotation burn policy. A corresponding reduction in simulated appropriations for fighting wildfires was also demonstrated. 相似文献
143.
Dennis W. Callaghan Sara S. Callaghan Robert A. Comerford 《Environmental management》1977,1(3):227-234
Given the ecological burden imposed by power plants located in the coastal zone, efforts to improve the marginal benefits realized from their operation are warranted. Indeed, if this source of environmental pollution can be utilized to compensate for past ecological damage, then the benefits will be magnified many-fold.This study addresses the economic feasibility of utilizing heated effluent water from power plants to invigorate the growth of oysters raised under controlled conditions. The preliminary findings indicate that given proper combinations of system capacity, supplemental nutrient supplies, sea water flow and temperature gradients, such an operation is feasible.This is also a demonstration of a viable application of a sophisticated computer modeling approach to environmental problems. System Dynamics a technique pioneered at the Massachusetts Institute of Technology, is applied to evaluate the physical, biological, and economic interrelationships of the aquacultural system variables. It offers many advantages for the environmental manager and researcher, a number of which are realized in the present investigation. 相似文献
144.
潮湿引起感烟火灾探测器误报研究 总被引:1,自引:0,他引:1
针对潮湿现象成为典型的火灾探测误报源 ,在火灾探测综合模拟实验平台中 ,通过收集水沸腾形成的水雾进行加湿 ,研究了冬季与夏季潮湿环境 ,对散射型光电感烟火灾探测器的发生误报影响。通过比较探测器的输出值与其附近湿度变化曲线 ,从原理上分析了误报发生的原因。实验结果表明 :在气温较低的冬季 ,水蒸气较易形成液态小水珠 ,容易导致感烟探测器误报警 ,而在夏季由于气温较高 ,这种情况较难发生。对相对湿度较高或达到饱和湿度 ,以及非火灾因素的雾气或微细水珠 ,对感烟探测器可靠性的影响 ,开展下进一步的工作进行了展望 相似文献
145.
碳二馏分加氢反应装置火灾爆炸危险性评价 总被引:3,自引:1,他引:3
运用美国道化学公司的火灾爆炸危险指数评价方法 (第七版 ) ,对碳二馏分加氢反应装置的火灾爆炸危险性进行了定量计算和评价 ,其结果表明 ,该装置的火灾爆炸危险等级为“非常大”。为了降低该装置的危险程度 ,笔者提出了采取有效的安全补偿措施 ,以降低单元的危险程度的新思路。通过分析表明 ,针对部分补偿系数对装置进行安全改进 ,能有效地降低其危险性等级 ,同时可以为避免重大危险源火灾爆炸事故 ,提供切实可行的手段和途径。 相似文献
146.
A land management history for central Queensland,Australia as determined from land-holder questionnaire and aerial photography 总被引:1,自引:0,他引:1
Features of the land management history over a 125,755 km(2) area of central Queensland, Australia were determined from a variety of sources. A random sample of 205 site locations provided the basis for determining trends in land use. Trends in vegetation clearing were determined using sequential aerial photography for the sample sites, revealing a steady rate averaging nearly 1% of the region per annum over 41 years. This measure of sustained clearing over a large region is higher than recently published clearing rates from South America. Land types have been selectively cleared with over 90% of the Acacia on clay land type having been cleared. A land-holder questionnaire pertaining to the random sites yielded a response rate of 71% and provided information on vegetation clearing, ploughing, tree killing (ring-barking or tree poisoning), and fire frequency, season and intensity. The land-holder responses were compared with independent data sources where possible and revealed no mis-information. However, land-holders may have been marginally less likely to respond if the sample area had been cleared, although this effect was not statistically significant. Ploughing and tree killing are variable depending on land type, but the former has affected about 40% of the Acacia on clay land type, effectively eliminating options for natural regrowth. The proportion of decade-site combinations that were reported as having no fires increased from 22% in the 1950s to an average of 42% for subsequent decades, although the reporting of more than one fire per decade has been relatively constant through the study period. The reporting of at least one fire per decade varies from 46% for the Acacia on sand land type to 77% for the Eucalypt on sand land type for decade-site combinations. Fires are more intense when associated with clearing than in uncleared vegetation, but the proportion of cool and hot fires is relatively constant between land types in uncleared vegetation. Nearly all fires reported were either in spring or summer and this seasonally restricted regime is probably at variance with Aboriginal fire regimes. This study describes the rapid transformation of central Queensland. This has yielded substantially increased agricultural production but may also result in a range of negative impacts and these are discussed. 相似文献
147.
采空区火源位置探测技术现状及发展方向 总被引:3,自引:0,他引:3
概述了国内外采空区火源位置探测技术的现状,着重介绍了温度探测法、气体探测法、磁力探测法、数理解算法、电磁波探测法及电阻探测法等探测技术,并展望了国内外采空区火源位置探测技术的发展方向 相似文献
148.
油品引燃时间的影响因素研究 总被引:2,自引:1,他引:1
以激光作为强辐射源对煤油,轻柴油和重柴油进行了直接引燃试验,研究了引燃时间受入射辐射热强度,油品性质和热辐射入射角度影响的关系。 相似文献
149.
液化石油气罐区危险性的定量评价 总被引:2,自引:0,他引:2
液化石油气罐区的主要危险是贮罐区发生火灾、爆炸事故。运用数学模型对液化石油气贮罐的危险性进行定量化评价,估算其爆炸事故的严重程度、波及范围、影响程度等 相似文献
150.