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181.
Earthquake prediction practice and a large number of earthquake cases show that anomalous images of small earthquake belts may appear near the epicenter before strong earthquakes. Through the research of earthquake cases, researchers have a relatively consistent method to determine the clarity of an identified seismic belt, but there is still a lack of method on seismic belt identification from the distribution of scattered points. Due to the complexity of exhaustive algorithm, the rapid automatic identification technique of seismic belts has been progressing slowly. Visual recognition is still the basic method of seismic belt identification. Based on the algorithm of distance correlation, this paper presents a fast automatic identification method of seismic belts. The effectiveness of this method was proved by 100 random earthquakes and an example of seismic belts of magnitude 4.0 before the 2005 Jiujiang M5.7 earthquake. The results show that: ① the automatic identification of seismic belts should first identify the “relational earthquake”, then identify the “suspected seismic belt”, and finally use the criterion of seismic belt clarity to determine; ② random earthquakes and real earthquakes identification results show that the distance correlation method can realize the fast automatic identification of seismic belts by computer.  相似文献   
182.
郭有明  冯祥胜 《气象》1996,22(12):14-16
该文简述用关系数据模型的预报工作单描述天然预报数据库的逻辑结构,得到了更加直观的预报区域的四维时空结构,更加利于交互操作和关系数据库技术的支持。  相似文献   
183.
钻孔灌注桩压浆后的承载性能研究   总被引:15,自引:0,他引:15  
根据某大厦及邻近场地试桩的静载荷及桩身应力测试结果,对压浆后桩的承载性能进行了深入地分析。未压浆桩的荷载-沉降关系符合双曲线函数,而压浆后桩的荷载-沉降关系符合幂函数。在极限状态时桩端阻力占总荷载比例为6.4 %~ 18.4 %,桩侧阻力占总荷载比例为81.6 %~93.6 %,且随着桩顶荷载的增加,桩端阻力所占比例快速增长。根据极限承载力外推值, 桩侧、桩端压浆的极限承载力提高幅度为89.85 %~147.81 %, 桩端压浆的极限承载力提高幅度为30.08 %~81.78 %。根据灰色关联分析,无论哪种压浆工艺,起主要作用的是压浆总量,且桩端压浆的影响大于桩侧压浆。  相似文献   
184.
贸易网络研究起源于复杂网络科学,其研究问题属于经济地理学全球化关注范畴。然而,关系经济地理作为经济地理全球化研究的中坚力量,同样借鉴社会网络和网络科学的思想,几乎没有参与到贸易网络的研究和对话中。论文针对这一现象,从介绍关系经济地理的网络范式入手,阐述关系经济的网络范式来源、过程与研究成果,并梳理现有贸易网络研究的进展,分析现阶段关系经济地理的网络思潮与贸易网络的区别,重新思考经济地理在关系视角下,应该以何种方式参与到贸易网络的讨论中。主要结论如下:(1)关系经济地理的网络范式仅仅借用社会网络研究小部分概念,重视在整体网络空间中行动者的嵌入性,几乎不关注网络的整体结构及其对集体行为的影响;(2)贸易网络研究主要探讨国家间贸易网络的结构与性质,而关系经济地理普遍从企业出发研究贸易流动背后的生产网络,其理论基础难以使用社会网络分析方法;(3)关系经济地理的贸易网络研究应该重视全球集群网络理论的运用,重新思考网络概念的经济地理学基础和多维网络相互耦合关系研究等问题。论文有助于推动关系经济地理学学者如何借助学科理论基础参与到贸易网络国际化研究中,对探讨现阶段经济地理理论应用和新方法实践具有重要...  相似文献   
185.
气象结构化数据包含地面小时数据、地面分钟数据等多种数据种类,在分析和调用中需要利用时间属性和空间属性。随着数据量日益增大,高并发、复杂统计条件下的查询与统计对数据库的效率要求十分严苛。在此背景下,传统的关系型数据库逐渐难以满足实时应用需求。本文使用不同类型的分布式数据库和关系型数据库,结合气象业务使用场景,探索多种类型下数据库的使用性能,研究不同场景的性能差异与不同数据库架构框架之间的关系,以提高数据服务实时响应能力。  相似文献   
186.
安邦河湿地浮游植物数量与环境因子相关性研究   总被引:5,自引:0,他引:5  
2005年7月-2006年5月,对安邦河湿地浮游植物数量及其环境因子监测,运用相关分析和灰关联分析对其浮游植物数量与环境因子关系进行研究.相关分析结果显示,浮游植物数量与水温呈显著正相关(p<0.01);与DIN在春季呈显著正相关(p<0.01),在夏、秋季呈显著负相关(p<0.05,p<0.01);与DIP在各个季节均呈显著正相关(p<0.01,p<0.05);与溶解氧呈正相关,在春季和秋季相关显著(p<0.05,p<0.01),在夏季相关不显著(p>0.05);与透明度呈正相关,但相关均不显著(p>0.05);与pH值呈负相关,且在春季、夏季呈显著相关(p<0.01);灰关联分析结果表明,对安邦河湿地浮游植物数量影响最大的DIP,因此控制外源性的DIP的输入对于维持安邦河湿地生态系统的健康是非常重要的.  相似文献   
187.
韩长寿 《矿产与地质》2010,24(6):489-494
河南省境内北秦岭构造带在EW向存在明显的地质差异,主要表现在自W向E构造层次加深、岩石变质程度变深、矿产组合由复杂到单调。其形成原因主要有板块敛合时渐次碰撞因素、逆冲推覆构造运动的影响和后期断裂造成的地层升降作用。  相似文献   
188.
We have developed a new database named GeoReM ( http://georem.mpch-mainz.gwdg.de ) for reference materials and isotopic standards of geochemical and mineralogical interest. Reference samples include rock powders originating from the USGS, GSJ, GIT-IWG, synthetic and natural reference glasses originating from NIST, USGS, MPI-DING, as well as mineral (e.g., 91500 zircon), isotopic (e.g., La Jolla, E&A, NIST SRM 981), river water and seawater reference materials. GeoReM is a relational database, which strongly follows the concept of the three EARTHCHEM databases. It contains published analytical and compilation values (major and trace element concentrations, radiogenic and stable isotope ratios), important metadata about the analytical values, such as uncertainty, uncertainty type, method and laboratory. Sample information and references are also included. Three different ways of interrogating the database are possible: (1) sample names or material types, (2) chemical criteria and (3) bibliography. Some typical applications are described. GeoReM currently (October 2005) contains more than 750 geological reference materials, 6000 individual sets of results and references to 650 publications.  相似文献   
189.
The Permian Lopingian in the Dianqiangui Basin and its adjacent areas is marked by the coal measures of the Wuchiapingian and the carbonate strata of the Changhsingian stages. For the Lopingian of the Dianqiangui Basin and its adjacent areas,the diversity of sedimentary facies and the obviousness of facies change provide an advantaged condition on a study of sequence stratigraphy. Approximately,the Wuchiapingian stage constitutes a third-order sequence and the Changhsingian stage forms an-other. For the Wuchiapingian stage in the study area,coal-measures were developed on the attached platform and,in addition,a special coal-measure that is composed of both limestone beds and coal beds was also developed in the central part of some isolated platforms. Grain-bank grainstones and packstones were formed on the margin of the attached platform as well as in the windward part of iso-lated platforms. For the Changhsingian stage in the study area,open-platform limestones were formed on the attached platform,while sponge-reef limestones were developed both on the margin of the at-tached platform and on the isolated platforms. The Lopingian Series is a set of basin-facies muddy shales with interbeds of silicalites in the inter-platform basin,which appears a set of the large-thick coarse clastic strata of molasses covering direct the deep-water strata from the Devonian to the Per-mian Yangsingian in the Qinzhou-Fangcheng region in the southern part of the study area. All of these features indicate the complexity of temporal-spatial facies-changes. Sequence-stratigraphic frame-works could be established,which would illustrate two types of facies-changing surfaces and dia-chronisms in the stratigraphic records,based on the combination of both biostratigraphic and chronostratigraphic materials and the regularity reflected by temporal evolutionary succession of sediments as well as spatial distributional patterns of sedimentary facies. Ultimately,features of sedi-mentary succession and palaeogeographical evolution of the Permian Lopingian in the study area are revealed clearly in a series of the panel diagrams of sequence-stratigraphic frameworks and the outline maps showing the sedimentary-facies and palaeogeography. The Permian Lopingian formed by two third-order sequences differs from the stratigraphy of the same era characterized by the constant re-gression along Euramerica. Most specially,if the end-Guadalupian mass-extinction event is genetically related to a regressive event represented by the unconformity of the first episode of the Dongwumovement in the study area,the mass-extinction event at the turn from the Permian to the Triassic is genetically related to a rapid transgressive event re-flected by the drowning unconformity in the study area. These phenomena might reveal a complex rela-tionship between mass-extinction events and trans-gressive-regressive events.  相似文献   
190.
从逻辑上概括了基本的二维空间关系,描述新增的查询需求,阐述如何通过关系运算,推演出正确结果,在文章最后给出具体的例子,并对查询的问题作了些简单的总结。  相似文献   
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