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飞机座舱工效多级模糊评价研究   总被引:4,自引:1,他引:4  
主要从系统工程角度 ,对飞机座舱工效多级模糊评价方法中的评价因素集、因素权重值、模糊评价矩阵以及综合评价方法等的确定 ,进行了初步探索。在此基础上 ,构造了模糊评价矩阵、因素权重值数据库流程图 ,为飞机座舱工效的总体评价及其数据库系统的建立奠定了基础。最后 ,简单讨论了现存的问题及今后进一步的研究方向  相似文献   
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In many tropical developing countries, the twin pressures of population and poverty are resulting in substantial fragmentation of forests, increasing the probability of extinction for many species, Forest fragmentation occurs when large contiguous forests are perforated by small holes or broken up into edges and smaller patches to form a nonforested matrix of open spaces. Thus, forest fragmentation refers not only to the area of forest cleared, but also to the pattern of this clearance, the resulting forest’s spatial properties. Both characteristics are important for species survivability. Apart from opening up forests to many abiotic and biotic influences, fragmentation can affect species dispersal and migration through its effects on forest connectivity. Landscape ecology conceptualizes connectivity as a gradient of critical thresholds, ranging from the large intact forest to the small unconnected forest patch. This article reports results from a multiple-scale analysis of forest fragmentation in Jamaica’s Cockpit Country, an area of once contiguous forest now under threat from human encroachment. Spatial forest data derived from classification of ETM+ satellite imagery are used to measure fragmentation patterns representing various degrees of forest connectivity and density. The results suggest that, overall, 81% of the region is in forest. However, fragmentation patterns also suggest that this forest is riven with extensive perforations indicative of an early stage in the decline of contiguity. The results provided by the spatial fragmentation model are a first step in the design of effective conservation and rehabilitation plans for the area. The article concludes with a discussion of possible multiscale management options for the region.  相似文献   
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飞机座舱设计人机工效评价探讨   总被引:7,自引:0,他引:7  
利用模糊数学的理论 ,建立座舱设计方案的工效学评价体系。体系中采用多级模糊评价 ,对评价指标隶属度、评价指标权重均进行了考虑 ,为座舱工效设计评定研究奠定基础。  相似文献   
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