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821.
1998年中国洪灾与减灾对策   总被引:4,自引:0,他引:4  
分析了 1998年中国洪灾的原因 ,并提出了相应的防灾、减灾对策  相似文献   
822.
1INTRODUCTION Human Capital Theory(HCT)'s idea origin recalls westernclassical political economics in the eighteen century.HCTcame into being in the middle and later periods of the20century,sprang up in the1960s and1970s,was introducedinto China in the1980s and is still one of the hotspotsin economic research.Foreign and domestic scholars havemade a lot of deep researches and important achievements.2FOREIGN RESEARCHIn the1950s,facing many"economic enigma"such as"Solow residual"an…  相似文献   
823.
中国火灾最佳灰色回归组合预测模型   总被引:4,自引:6,他引:4  
火灾现象具有随机性、模糊性,是个复杂的灰色系统行为。研究火灾发生的规律及发展趋势,具有实用价值。笔者给出最小二乘估计意义下的最佳组合预测模型的定义,并求得其权的公式和证明权的惟一性;用回归分析方法建立多个回归模型,并按3条标准即①回归指数大、②系统误差小、③模型精度高,选定最佳非线性回归模型;用灰色理论建立多个灰色模型,并按3条标准即①后验差比值小、②小误差概率大、③预测关联度大,选定最佳灰色模型;再将最佳回归模型与最佳灰色模型有机地结合起来建立中国火灾最佳灰色回归组合预测模型。组合预测模型综合利用前两者提供的不同的有用信息,改善了单一模型的局限性,提高了预测精度,减少了预测误差。组合模型预测中国年火灾起数处于动态增长过程。  相似文献   
824.
孟威  苏勤  王浩  陆恒芹 《资源开发与市场》2006,22(6):502-505,537
资源驱动型旅游地中心城市是我国普遍存在的一种旅游城市类型,但对这类城市形象的研究相对较少。以黄山市屯溪区为例,在感知形象测度的基础上,利用定性与定量方法论结合分析其感知形象现状和问题,并提出解决方案,总结出该类型城市在形象建设中应当注意的四对矛盾。  相似文献   
825.
湘江流域洪水灾害综合风险评价   总被引:26,自引:4,他引:26  
依据灾害系统理论,在综合考虑致灾因子、孕灾环境和承灾体的基础上,从致灾因子、孕灾环境的自然属性和承灾体的社会属性两方面出发,以县级行政单元为基本评价单元,进行了湘江流域洪水灾害的综合风险评价。在综合考虑降雨量、地形以及历史上洪水灾害发生频次等自然因素的条件下,利用地图代数分析得到了湘江流域洪水灾害危险性评价图;在综合考虑人口密度、耕地面积百分比、人均GDP和单位面积水库和塘坝容量等社会经济指标的基础上,利用模糊综合评判法得到了湘江流域洪水灾害脆弱性评价图。在此基础上采取“乘”模型的计算公式,即风险=危险性×脆弱性,将湘江流域洪水灾害风险划分为高风险、较高风险、中等风险、较低风险和低风险5个等级,并借助地理信息系统软件编制了湘江流域洪水灾害综合风险等级评价图。  相似文献   
826.
A submicroscopic genomic duplication in Xq22.2 that contains the entire proteolipid protein 1 gene (PLP1) is responsible for the majority of Pelizaeus–Merzbacher disease (PMD) patients. We previously developed an interphase FISH assay to screen for PLP1 duplications in PMD patients using peripheral blood and lymphoblastoid cell lines. This assay has been utilized as a clinical diagnostic test in our cytogenetics laboratory. To expand usage of the interphase FISH assay to prenatal diagnosis of PLP1 duplications, we examined three PMD families with PLP1 duplications utilizing aminiotic fluid samples. In two families the FISH assay revealed fetuses with PLP1 duplications, whereas the other fetus showed a normal copy number of PLP1. Haplotype analyses, as well as an additional FISH analysis using postnatal blood samples, confirmed the results of the prenatal analyses. Our study demonstrates utility of the interphase FISH assay in the prenatal diagnosis of PLP1 duplications in PMD. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   
827.
PROBLEM: Low back pain (LBP) is one of the most prevalent work-related conditions affecting employed populations in developed countries, yet little is known about this condition among the world's largest, single-nation labor force: The People's Republic of China. METHOD: This is a cross-sectional study of the prevalence of low back pain (LBP) among garment workers, battery/kiln workers, and teachers in Shanghai, People's Republic of China. Data were collected by personal interview and physical examination at six work sites. The overall response rate was 78%. RESULTS: The overall (N=383) self-reported annual prevalence of LBP symptoms lasting 24 hours or more was 50%. Garment workers had a higher annual prevalence of LBP (74%) than teachers (40%), prevalence ratio (PR=1.9, 95% CI=1.4-2.4). DISCUSSION: The overall annual prevalence of self-reported LBP (50%) was higher than that reported among 50 other Chinese employed study populations (30%). Healthy worker effects may have limited the conclusions from this cross-sectional study. SUMMARY: These results suggest that LBP is a prevalent condition in Chinese workers and that more work should be done to estimate its impact on the Chinese workforce. The findings for garment workers were consistent with increased risk of LBP among persons doing work in fixed, sedentary postures.  相似文献   
828.
Wu JY  Lindell MK 《Disasters》2004,28(1):63-81
The idea of pre-impact recovery planning has recently been promoted by researchers and practitioners, but very little research has been done to evaluate its effects on disaster recovery. This study compared two jurisdictions — the city of Los Angeles, California and Taichung county in Taiwan — in their recovery from earthquakes. Although the two cases also differ with respect to variables other than the presence of pre-impact recovery plans, the available data suggest that having a pre-impact recovery plan facilitates housing reconstruction and allows local officials to make more effective use of the window of opportunity after disaster to integrate hazard mitigation into the recovery process.  相似文献   
829.
The rapid growth of rural enterprises has transformed the Chinese countryside. Although rural industrialisation has resulted in increased financial well-being, it has also contributed to decreased environmental quality. While China has strong environmental protection laws, this paper will demonstrate that they are not being effectively implemented in a rural region in Zhejiang Province. This is due to a number of social, political, and economic barriers that prevent agencies from effectively enforcing environmental policies and regulatory mechanisms. This paper investigates the implementation of China's environmental policies through a case study in Yuhang County, Zhejiang Province. It demonstrates that the implementation of environmental impact assessment, discharge fees, and limited time treatment is limited by inadequate technology, low finances, limited human resources, poor public environmental awareness, faulty data, inferior agency reports, organizational conflict, relations based on guanxi, and low discharge fee prices.  相似文献   
830.
战略环境评价(SEA)及其研究进展   总被引:43,自引:0,他引:43  
战略环境评价(SEA)是目前环境评价领域中令人关注的前沿课题 .本文对 SEA的提出和发展进行了回顾 ,对国外开展SEA的实践进行了归纳分析 ,探讨了 SEA的作用、区域特征、评价因素、基本程序、技术方法和机制 ,论述了 SEA与项目 EIA的关系 ,并介绍了香港和内地 SEA的初步实践 .  相似文献   
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