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101.
Spatial Accessibility to Health Care Facilities in Suhum District,Ghana   总被引:1,自引:1,他引:1  
To improve geographical accessibility to health facilities in rural Ghana, it has been recommended that additional health facilities be built. Resource constraints make this recommendation infeasible. Using location-allocation models, this paper demonstrates that in the Suhum District of Ghana substantial improvements in accessibility can be achieved with better locational choices and without additional facilities. Also, additional facilities will produce little improvement in accessibility if location is not explicitly considered. The paper demonstrates the utility of location-allocation models for improving accessibility to services in the Third World.  相似文献   
102.
The change in atmospheric relative humidity affects the physical and optical properties of aerosol particles. It would be interesting to study the effect of an increase in relative humidity on the angular scattering of light by aerosols (by incorporating the changes due to it as the complex refractive index and the parameters of the size distribution function). In the present paper we have computed the angular scattering function for rural and urban aerosols, for light of wavelength 0.55 μn. The results obtained for these two models, representative of different environments, are interesting and show some discriminating features.  相似文献   
103.
The seasonal and diurnal variations of ozone mixing ratios have been observed at Niwot Ridge. Colorado. The ozone mixing ratios have been correlated with the NO x (NO+NO2) mixing ratios measured concurrently at the site. The seasonal and diurnal variations in O3 can be reasonably well understood by considering photochemistry and transport. In the winter there is no apparent systematic diurnal variation in the O3 mixing ratio because there is little diurnal change of transport and a slow photochemistry. In the summer, the O3 levels at the site are suppressed at night due to the presence of a nocturnal inversion layer that isolated ozone near the surface, where it is destroyed. Ozone is observed to increase in the summer during the day. The increases in ozone correlate with increasing NO x levels, as well as with the levels of other compounds of anthropogenic origin. We interpret this correlation as in-situ or in-transit photochemical production of ozone from these precursors that are transported to our site. The levels of ozone recorded approach 100 ppbv at NO x mixing ratios of approximately 3 ppbv. Calculations made using a simple clean tropospheric chemical model are consistent with the NO x -related trend observed for the daytime ozone mixing ratio. However, the chemistry, which does not include nonmethane hydrocarbon photochemistry, underestimates the observed O3 production.  相似文献   
104.
新时期农村产业结构优化调整研究   总被引:4,自引:0,他引:4  
通过在农村长期的工作实践和对农村经济发展的考察,依据当前国内外发展对农村产业经济发展的要求,分析研究我国和河南省农村产业结构的发展现状和动态变化,提出农村产业结构调整的指导思想、原则及目标,据此,从农村产业结构调整、农业产业结构调整和种植业结构调整3个层次,研究提出农村产业结构调整的基本思路和方向,为有关部门决策农村经济发展提供科学依据.  相似文献   
105.
The Australian Census of Population and Housing is a census of people not places. However, where people live and work can be of major relevance in our search for explaining and understanding their behaviour. This paper argues that the place dimension in the Australian census has not been exploited very effectively in this respect. Three dimensions of the issue are addressed. Firstly, the spatial units commonly used for analysis of census data often are not appropriate to the problem being investigated. The spatial units in the Australian Standard Geographical Classification (ASGC) used for census data rarely represent meaningful social, economic and environmental regions. Secondly, the use of a simple urban/rural dichotomy is criticised as being a very blunt instrument to differentiate settlement types. Thirdly, the relationship between people and place in the census is discussed. While for the most part the census relates people to a single location—their place of usual residence—this is only one of the places with which people regularly interact. It is suggested that there is a need to adopt practices in the census which allow a range of population geographies to be defined. In conclusion it is argued that innovation in the Australian census, especially with the introduction of meshblocks and contemporary methodology and technology in Geographical Information Systems, makes it possible to analyse spatially referenced data in ways that can address these three issues.  相似文献   
106.
程先云  刘洪禄  郑凡东 《水文》2007,27(6):42-45
引入水箱模型进行城市地下排水设施降雨一侵入水的模拟,探讨了初期蓄流值对模拟结果的影响并提出了相应的解决办法;由于模型参数多、非线性,参数的率定采用通用优化分析计算平台PowerFit,并获得了满意的结果,表明:①水箱模型适用于地下排水设施雨洪模拟和预测,可为市政规划设计和城市灾害预报提供可靠依据;②PowerFit全局优化能力强、简单易用,可广泛应用于水利水电等工程领域中的优化计算。  相似文献   
107.
城市发展空间外拓对其边缘区乡村影响较大,旅游化是乡村发展过程中有别于工业化的一种形式.在对山东省日照市王家皂村农户问卷调研所得数据基础上对旅游化的效应进行评价,得出:旅游化使得村民旅游经济收入得以迅速增加;村民就业结构发生较大变化,农村劳动力向单部门经济转移;村民旅游参与意识增强,对旅游经济前景普遍看好;生活环境与质量发生改变,社区问题开始显现;正、负旅游示范效应影响并存,社区社会生态平衡面临挑战等结论,并对旅游化效应的社会意义进行了探讨.  相似文献   
108.
109.
运用旅游心理学原理,采用比较分析和交互分析等研究方法,分析了上海市居民乡村旅游的人口学特征、行为偏好以及效果感知,并提出加强乡村旅游宣传力度、观念创新和服务管理等建议.  相似文献   
110.
通过对国内开展乡村旅游现状的调研,分析了目前福建开展乡村旅游存在的问题,借鉴川、渝、浙等地乡村旅游"农家乐"的成功经验,结合福建依托森林资源特色开展森林人家的主要措施,对如何进一步提升森林人家品牌进行了探讨.  相似文献   
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