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71.
西畴县灾害性天气预报经验 总被引:1,自引:0,他引:1
统计西畴县近30年的大雨、暴雨、冰雹等灾害性天气时空分布情况,查阅历年预报会商分析记录和实况天气回顾,找出了造成这类天气的实际影响系统,归纳出该县的四季天气特点、主要气象灾害和主要影响天气系统,着重讨论形成西畴县冰雹、大雨、暴雨天气的典型环流形势和其它影响因子。对形成西畴县冰雹、大雨、暴雨等灾害性天气预报进行经验总结。 相似文献
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73.
光压模型是导航卫星高精度定轨、定位的基础。目前关于北斗卫星光压摄动模型的研究并不少见,但基于卫星物理参数的综合解析模型建立与应用公开可见的论述并不多见。不同于其他保守和非保守摄动力,光压辐射与卫星本身参数状态密切相关,具有明显的个体差异性。本文基于光压辐射的物理机理、北斗卫星物理参数、姿态控制模式等,建立光压摄动综合解析模型,以精密星历和激光测距数据为基准,验证了综合解析模型能够获得分米级的精密定轨精度。在此基础上,根据卫星角动量守恒和在轨遥测参数变化,分析了综合解析模型和在轨实际干扰力的差值,提出了在综合解析模型基础上增加常数经验修正项Da、Ya的方法,以北斗C08、C10星为例,分别可获得0.078、0.084 m的SLR检核精度,相比于利用CODE经验改进模型,精度分别提高0.021、0.045 m。 相似文献
74.
There is increasing policy and research interest in disaster resilience, yet the extant literature is still mired in definitional debates, epistemological orientations of researchers, and differences in basic approaches to measurement. As a consequence, there is little integration across domains and disciplines on community resilience assessment, its driving forces, and geographic variability. Using US counties as the study unit, this paper creates an empirically-based resilience metric called the Baseline Resilience Indicators for Communities (BRIC) that is both conceptually and theoretically sound, yet, easy enough to compute for use in a policy context. A common set of variables were used to measure the inherent resilience of counties in the United States according to six different domains or capitals as identified in the extant literature – social, economic, housing and infrastructure, institutional, community, and environmental. Data were from public and freely accessible data sources. Counties in the US Midwest and Great Plains states have the most inherent resilience, while counties in the west, along the US-Mexico border, and along the Appalachian ridge in the east contain the least resilience. Further, it was found that inherent resilience is not the opposite of social vulnerability, but a distinctly different construct both conceptually and empirically. While understanding the overall variability in resilience, the BRIC is easily deconstructed to its component parts to provide guidance to policy makers on where investments in intervention strategies may make a difference in the improvement of scores. Such evidence-based research has an opportunity to influence public policy focused on disaster risk. 相似文献
75.
《The Journal of geography》2012,111(5):183-184
Abstract Interim semester field trips provide a unique opportunity for undergraduate students to collect field data in support of their capstone research experience. We encourage students to participate in collaborative research projects prior to the semester for which they enroll in the capstone course. Students select a research project based on a field trip itinerary, submit a research proposal to faculty, conduct preliminary research prior to departure and collect data in the field during a January “Winterim” course. During the spring semester, students continue laboratory research, incorporating data collected in the field to complete their research project and prepare scientific presentations. Field trips provide an inherent mentoring system whereby faculty interact with students, and underclass students collaborate on capstone research projects. This approach facilitates learning by emphasizing preparation and planning, collaborative learning and integration of classroom knowledge into field research. 相似文献
76.
《The Journal of geography》2012,111(1):6-24
Creating opportunities for students to actively apply hazards theory to real-life situations is often a challenge in hazards geography courses. This article presents a project, the Jocko Lakes Fire Project, that implemented learning strategies to encourage students to be active in wildfire hazards research. Wildfire hazards stand out as an increasing threat to communities in forested areas given current and projected rates of urbanization, the growing concentration of wealth in hazard-prone areas, the increasing costs of forest wildfire reduction, and climate change. Components of the project involved students in problem definition and the articulation of a research plan; identifying and collecting relevant data; and analyzing and documenting the wildfire hazard event. The student-based evaluation of the project and its outcomes highlights the ways in which this approach can increase understanding of local hazard scenarios, familiarity with relevant theory, geographical knowledge, and skills in research. 相似文献
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78.
本文对几何不等式问题做些推广,并提出了广义几何不等式,通过构造随机变量,利用随机变量数学期望的概率性质,给出几何不等式及广义几何不等式的概率证明,最后给出几何不等式的一个直接应用,所得的结果是文献(1-4)的补充和拓广。 相似文献
79.
Place and Health: Towards a Reformed Medical Geography* 总被引:1,自引:0,他引:1
Robin A. Kearns 《The Professional geographer》1993,45(2):139-147
An engagement with public health concerns and aspects of social theory such as the structure/agency debate is crucial to medical geography. The imperatives underlying this engagement center on place, a geographical concept which is prominent in both social theory and recent health philosophy. Without detracting from its distinguished heritage, this reformed medical geography will analyze issues such as the consequences of illness and health service provision for both personal well-being and the collective experience of place by communities. 相似文献
80.
在静力触探应用中有关土层分类命名问题的探讨 总被引:1,自引:0,他引:1
多年来,静力触探的土层分类命名一直是困扰勘察设计人员的大问题,以静力触探资料整理中的普通经验及铁道部《静力触探技术规则》(TB37-93)中有关土类划分内容,结合勘察实践做些讨论,指出“普遍经验”的局限与相关规范的优缺点,并尝试提出新的工作方法和见解。 相似文献