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This paper presents the technical aspects of a new methodology for assessing the susceptibility of society to drought. The methodology consists of a combination of inference modelling and fuzzy logic applications. Four steps are followed: (1) model input variables are selected—these variables reflect the main factors influencing susceptibility in a social group, population or region, (2) fuzzification—the uncertainties of the input variables are made explicit by representing them as ‘fuzzy membership functions’, (3) inference modelling—the input variables are used to construct a model made up of linguistic rules, and (4) defuzzification—results from the model in linguistic form are translated into numerical form, also through the use of fuzzy membership functions. The disadvantages and advantages of this methodology became apparent when it was applied to the assessment of susceptibility from three disciplinary perspectives: Disadvantages include the difficulty in validating results and the subjectivity involved with specifying fuzzy membership functions and the rules of the inference model. Advantages of the methodology are its transparency, because all model assumptions have to be made explicit in the form of inference rules; its flexibility, in that informal and expert knowledge can be incorporated through ‘fuzzy membership functions’ and through the rules in the inference model; and its versatility, since numerical data can be converted to linguistic statements and vice versa through the procedures of ‘fuzzification’ and ‘defuzzification’.  相似文献   
54.
We tested separately the effect of two taxonomically related rotifers (B. patulus and B. macracanthus) on the population dynamics of another species (A. fissa) at low (0.5 ×10 6) and high food levels (1.5 × 106 cells/ml of Chlorella vulgaris) using different inoculation densities (0–100%). We also quantified the impact of A. fissa on the two brachionid species. Regardless of the presence of the competing species, an increase in the availability of food led to increase in the abundances of the three rotifers. The population growth of B. patulus, B. macracanthus, or A. fissa was affected negatively when cultured together with another species. An increase in the initial density of any one of the competing species became advantageous to maintain a certain population size. At a low algal food level, B. patulus was able to suppress A. fissa more strongly than B. macracanthus. On the other hand, at a high food level, B. macracanthus suppressed the population of A. fissa more strongly than B. patulus. Peak population densities for A. fissa varied from about 150 to 1000 ind./ml, depending on food density and the presence of competitors. The rate of population increase (r) of A. fissa, B. patulus, and B. macracanthus increased with an increase in food availability but decreased with increasing initial density of the competitor. Both Brachionus spp. experienced negative growth rates in the presence of A. fissa, especially at a high initial density of the latter. Published in Russian in Ekologiya, 2007, Vol. 38, No. 5, pp. 381–390. The article was submitted by the authors in English.  相似文献   
55.
警用头盔的人机工程学分析   总被引:2,自引:0,他引:2  
警用头盔是武警部队使用最为频繁的单兵防护用具,本文基于人机工程学的理论,用人机工程学的观点对武警部队现装备的警用头盔进行分析和探讨,提出解决途径的设想,展望警用头盔的发展前景。  相似文献   
56.
Estimation of waste generation from floods   总被引:1,自引:0,他引:1  
A framework of correlation for estimating the amount of waste generation from floods is developed. Flood waste data were collected from four recent typhoons in Taiwan. Parameters affecting the flood waste are analyzed. Population density, flooded area and amount of total rainfall are chosen as the correlating parameters for the model development, and regression diagnostics are performed to check the validity of the collected data. The simple linear model is shown to be incapable of correlating the flood waste data. An exponential model is proposed and shown to give acceptable correlation with the flood waste data spanning five orders of magnitude. The model can be useful in the planning of waste cleanup after floods.  相似文献   
57.
Seasonal variations in microcystin concentrations in Lake Taihu, China   总被引:1,自引:0,他引:1  
An enzyme-limited immunosorbent assay (ELISA) was used to monitor spatial and temporal variation of microcystins (MCs) in Lake Taihu. MC concentrations were higher in summer and autumn than in other seasons. Maximal MC concentration was 15.6 mug L(-1). Compared to central Lake Taihu and Wuli Bay, Meiliang Bay had higher MC concentrations due to high biomass of Microcystis.  相似文献   
58.
This study presents the chemical composition of dry deposition by using dry deposition plate and water surfaces sampler during daytime and nighttime sampling periods at a near highway traffic sampling site. In addition, the characterization for mass and water soluble species of total suspended particulate (TSP), PM2.5 and PM10 were also studied at this sampling site during August 22 to October 31 of 2006 around central Taiwan. The samples collected were analyzed by using Ion Chromatography (DIONEX 100) for the ionic species analysis. Results of the particulate dry deposition fluxes are higher in the water surfaces sampler than that of the dry deposition plate. In other words, the results also indicated that water surface can absorb more ambient dry deposition inorganic pollutants than that of dry deposition plate in this study. The results obtained in this study indicated that the ionic species of Cl(-), NO3(-) and SO4(2-) occupied about average 60-70% downward flux out of total ionic species for either dry deposition plate or water surfaces sampler during August to October of 2006 at this near highway traffic sampling site.  相似文献   
59.
While the world is going into different tourism expectations, the tourism understanding in Turkey is defined as tourism in the sea-sand-sun triangle. However, it is possible to contribute to the income and local development of the indigenous people by developing nature-based tourism. Besides, with the sustainable use and preservation of the natural-cultural assets, the damage of the traditional tourism industry on the natural and cultural environment could be reduced. In this study, it is aimed to bring up the nature-based tourism concept in Çanakkale by evaluating the nature-based tourism industry in the general of Turkey and assessing the natural-cultural resources that Çanakkale comprehends. The most important areas that have a nature-based tourism potential in Çanakkale and the tourism activities that are most suitable for these areas have been determined.  相似文献   
60.
四川汶川8.0级地震典型遗址遗迹综合评估   总被引:6,自引:2,他引:4  
简要介绍了四川汶川8.0级地震现场考察的有关情况,然后重点对地震典型遗址、遗迹的综合评估原则进行了详细研究,并在此基础上设计出综合评估量表.最后,对北川、映秀等典型地震遗址、遗迹进行了综合评估,并提出了保护建议.  相似文献   
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