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171.
利用江浙沪地区1644~1949年洪涝灾害数据库,基于年受灾县次,对该地区历史重大洪涝灾害年进行了辨识,并以历史重大洪涝灾害为情景,对其重现于2010年的人口和GDP物理暴露量进行分析,得到以下结论:(1)按受灾县次划分,1644~1949年江浙沪地区重大洪涝灾害频率在50~100年一遇的为1670年、1683年、1804年;100~300年一遇的为1823年、1849年;300年一遇的为1931年;(2)重大洪涝灾害暴露区主要集中于长江三角洲地区;(3)6次重大洪涝灾害情景下,人口物理暴露量基本超过2010年该区人口总量的40%,而GDP物理暴露量则几乎超过了其总量的50%;(4)江苏受灾最为明显,上海受灾幅度波动最大,尤其是在100年一遇洪涝灾害前后受灾影响差距很大,浙江受灾影响相对稳定;(5)该区人口、GDP物理暴露量并不一定与受灾县次呈典型的正相关关系,可能与其人口、经济分布格局等因素有关  相似文献   
172.
Due to growing environmental concern and increasing awareness among customers, reverse supply chain (RSC) has received much attention among researchers and practitioners. Therefore it is necessary to provide a comprehensive list of references for other researchers (or readers), who are interested in RSC research to help stimulate further interest. In this paper, we present classification schemes and a simple analysis for the reverse supply chain. This literature review was mainly based on journal articles but also included web based documents, conference materials, working papers, etc. A total of 543 articles were reviewed, of which 506 were published between 1967 and 2008 from 100 reputed international journals. Based on the literature review carried out and the nature of research observed in RSC, we have introduced two classification schemes to systematically organise the published articles. The first classification scheme is based on the content related issues on RSC and the second one is based on the solution methodology followed by the researchers. These classification schemes indicate that there is considerable research potential for RSC. The results also show that there is strong growth in RSC research.  相似文献   
173.
Abstract

Based on the data of historical geography, the analysis of the stratigraphic section, and the textual research of place names and satellite photographic interpretations, the authors study the formation and evolution of ancient lakes on the south coast plain of Laizhou Bay where there were once three lakes: Judian Lake, Qingshuibo Lake and Biehua Lake. All the lakes formed 6000 years ago evolved from the lagoons near the estuary and went through two periods, the golden age in the Middle Holocene and the shrinking age in the Late Holocene. The disappearance of the lakes resulted from the drying climate, the migration of the river courses and the activities of human beings. Among the three reasons, the migration of the river courses is the main one.  相似文献   
174.
国家重点文物旅游资源的开发利用--以河南省为例   总被引:3,自引:0,他引:3  
河南是我国重点保护文物(以下简称重点文物)大省,众多的古建筑、古遗址、古墓葬是河南旅游的主要吸引物。文章从分析了河南重点文物的开发现状,发现其文物旅游的优势和劣势,并结合均衡开发、循序渐进、三个效益并行、尊重历史剖面四个原则,提出了文物开发的五个策略:理顺管理体制、实现开发主体多元化、发挥自身优势突出特色旅游、加强基础设施建设和人才培养、加大营销力度、把科技引入文物开发。  相似文献   
175.
湖北省历史时期洪、旱灾害统计特征分析   总被引:10,自引:0,他引:10  
基于近2000年来的历史资料,对湖北省历史时期洪、旱灾害的统计特征及其演变规律进行了分析.结果表明:湖北省历史时期的洪、旱灾害经历了"少灾时期、增多时期与多灾时期"3个阶段,灾害出现的频率和影响的范围均呈增大趋势;洪旱灾害的空间分布呈现"洪水连江,干旱依山"的特点;洪旱灾害发生的季节集中性较强,中、大区域性洪水灾害集中在6-7月的梅雨季节,具有"梅汛"的特点,而旱灾以夏旱为多、春秋旱次之,严重的旱情多具有跨季节性的特点;总的来看,历史时期的洪旱灾害系交替进行,洪灾多于并重于旱灾.  相似文献   
176.
Background: Although numerous observational studies have demonstrated a protective effect of motorcycle helmets against head injury, the degree of protection against specific head injury types remains unclear. Experimental biomechanics studies involving cadavers, animals, and computer models have established that head injuries have varying etiologies. This retrospective cross-sectional study compared helmet protection against skull fracture, cerebral contusion, intracranial hemorrhage, and cerebral concussion in a consecutive series of motorcycle operators involved in recent traffic crashes in Kentucky.

Methods: Police collision reports linked to hospital inpatient and emergency department (ED) claims were analyzed for the period 2008 to 2012. Motorcycle operators with known helmet use who were not killed at the crash scene were included in the study. Helmet use was ascertained from the police report. Skull fracture, cerebral contusion, intracranial hemorrhage, and cerebral concussion were identified from International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) codes on the claims records. The relative risks of each type of head injury for helmeted versus unprotected operators were estimated using generalized estimating equations.

Results: Helmets offer substantial protection against skull fracture (relative risk [RR] = 0.31, 95% confidence interval [CI], 0.23, 0.34), cerebral contusion (RR = 0.29, 95% CI, 0.16, 0.53), and intracranial hemorrhage (RR = 0.47, 95% CI, 0.35, 0.63). The findings pertaining to uncomplicated concussion (RR = 0.80, 95% CI, 0.64, 1.01) were inconclusive. A modest protective effect (20% risk reduction) was suggested by the relative risk estimate, but the 95% confidence interval included the null value.

Conclusions: Motorcycle helmets were associated with a 69% reduction in skull fractures, 71% reduction in cerebral contusion, and 53% reduction in intracranial hemorrhage. This study finds that current motorcycle helmets do not protect equally against all types of head injury. Efforts to improve rotational acceleration management in motorcycle helmets should be considered.  相似文献   

177.
从环境类学术文献看中国环境教育存在的问题   总被引:5,自引:0,他引:5  
根据我国环境科学类期刊上刊登的环境教育文献的比重和内容的调查结果来看,我国环境科学界对环境以重视程度与环境教育的重要性不成比例,环境教育研究的落后已成为制约我国环境教育可持续发展的关键问题。  相似文献   
178.
重视现代信息技术的应用是专业图书馆的一个特点。本文从图书馆业务工作的自动化及文献信息服务的自动化两方面,阐述了如何利用新技术手段为科研人员服务。  相似文献   
179.
苍洱地区居址环境的历史变迁   总被引:1,自引:0,他引:1  
根据民族学和考古学资料进行的综合研究,可将苍洱地区居址环境划为4个历史变迁时期:4000多年前的先民们居住在沿海拔2500~2200米一线的一些向阳避风的苍山台地上。海拔2200~2000米一线的苍山脚下为汉晋时期先民们的聚居点。海拔2000米左右,沿滇藏公路一线的白族村落大致在唐宋南诏大理国时期形成。海拔1975米左右,今洱海边的白族村落大多数在元明清时期形成。其趋势是从高处往低处下移,随苍山上升,洱海水位下降,利用滩地形成新的居民群。其形成的间隔时间越来越短,加强洱海保护是迫切的任务。  相似文献   
180.
This paper evaluates the influence of different policy-related and scientific choices on the calculated regional contributions to global climate change (the “Brazilian Proposal”). Policy-related choices include the time period of emissions, the mix of greenhouse gases and different indicators of climate change impacts. The scientific choices include historical emissions and model representations of the climate system. We generated and compared results of several simple climate models. We find that the relative contributions of different nations to global climate change—from emissions of greenhouse gases alone—are quite robust, despite the varying model complexity and differences in calculated absolute changes. For the default calculations, the average calculated contributions to the global mean surface temperature increase in 2000 are about 40% from OECD, 14% from Eastern Europe and Former Soviet Union, 24% from Asia and 22% from Africa and Latin America. Policy-related choices, such as time period of emissions, climate change indicator and gas mix generally have larger influence on the results than scientific choices. More specifically, choosing a later attribution start date (1990 instead of 1890) for historical emissions, decreases the contributions of regions that started emitting early, such as the OECD countries by 6 percentage points, whereas it increases the contribution of late emitters such as Asia by 8 percentage points. However, only including the fossil CO2 emissions instead of the emissions of all Kyoto gases (fossil and land use change), increases the OECD contributions by 21 percentage points and decreases the contribution of Asia by 14 percentage points.  相似文献   
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