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41.
正20141538 Cao Qing(School of Earth Sciences and Engineering,Xi’an Petroleum University,Xi’an 710065,China);Zhao Jingzhou Characteristics and Significance of Fluid Inclusions from Majiagou Formation,Yichuan Huangling Area,Ordos Basin(Advances in Earth Science,ISSN1001-8166,CN62-1091/P,28(7),2013,p.819-828,7 illus.,3 tables,43 refs.)  相似文献   
42.
GEOCHEMISTRY     
正20142002 Wei Hualing(Institute of Geophysical and Geochemical Exploration,Chinese Academy of Geological Sciences,Langfang065000,China);Zhou Guohua Element Content and Mineral Compositions in Different Sizes of Soil in Tongling Area,Anhui Province(Geological Bulletin of China,ISSN1671-2552,CN11-4648/P,32(11),2013,p.1861  相似文献   
43.
正20141768 An Shaopeng(Institute of Rock and Soil Mechannics,Chinese Academy of Sciences,Wuhan 430071,China);Wei Lide Experimental Study on Mechanical Behavior of Xigeda Formation Siltstone and Structure Interface(Journal of Engineering Geology,ISSN1004-9665,CN11-3249/P,21(5),2013,p.702-708,9illus.,1 table,16 refs.)  相似文献   
44.
正20142564Chen Mingxing(Beijing Research Institute of Survey and Design,China Hydropower Engineering Consulting Group Co.,Beijing 100024,China);Chen Baoguo Application of Drilling Deviation Correcting and Deflecting Techniques in Geological Exploration at Songta Hydropower Station(Exploration Engineering,ISSN1672-7428,CN11-5063/TD,  相似文献   
45.
MINERALOGY     
正20141362 Chen Juan(Laboratory for High Temperature and High Pressure Study of the Earth’s Interior,Institute of Geochemistry,Chinese Academy of Sciences,Guiyang 550002,China);Li Heping Progress in Major Element and Trace Element Analysis of Sulfide Minerals(Acta Mineralogica Sinica,ISSN1000-4734,CN52-1045/P,33(3),2013,p.351-362,5 illus.,4 tables,20 refs.)  相似文献   
46.
PALEOBOTANY     
正20141605 Jin Peihong(School of Earth Science,Lanzhou University,Lanzhou 730000,China);Wang Zixi Early Cretaceous Fossil Plant from Qianliannaobao of Guyang,Inner Mongolia and Its Taphonomy Study(Gansu Geology,ISSN1004-4116,CN 62-1191/P,22(3),2013,p.19-27,1illus.,2tables,34refs.) Key words:floral studies,taphonomy,Inner  相似文献   
47.
The earliest known shaking table, driven by hand‐power, was constructed in Japan at the end of the 19th century. At the beginning of the 20th century developments had moved to the Stanford University in the U.S. with the introduction of an electric motor to produce a more refined oscillatory motion in one direction, the response of the testpiece being recorded mechanically by pens on a rotating drum. Major earthquakes in the 1920s prompted renewed interest at Stanford resulting in a uni‐directional table moving on rails, activated either by a pendulum striking at one end—the other being resisted by springs—or by a wheel with an eccentric‐mass attached to the table. A valuable feature here was that the size of the eccentric mass could be varied as the harmonic motion continued, thereby providing a method of control. In the 1950s, a similar pendulum input was used on a table constructed at the University of California, but instead of rails, it was supported by a group of vertical bars flexible in one direction only, and the 1939–1945 war had resulted in the availability of electrical devices for measuring response. Also, in Italy at this time the use of pendulums was augmented by contra‐rotating mass input devices giving better frequency control; arrays of several electrodynamic exciters were also used. In Japan, motion was induced by the release of compressed springs. The idea of producing input by an oil‐filled piston was introduced at MIT after the 1933 Long Beach earthquake to a table suspended from above by wires. Two other innovations here were of the greatest significance. First was an analogue device for using an actual earthquake record as input, and the second was control of the motion by an error‐driven electrically controlled feedback loop. The development of these ideas into the shaking tables, which we use today, had to wait upon the general development of control engineering during the 1939–1945 war, followed by progressively greater speeds in digital computation. This history ends (c.1985) after the continuation of these advances made possible full 6‐DOF control using many oil‐filled actuators, but before they became able to give us real‐time control with the attendant abilities of multi‐support input and the experimental study of inelastic behaviour. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
48.
《Urban geography》2013,34(3):187-211
Neighborhood variations in crime incidence rates are most commonly interpreted through the lens of social disorganization theory, or a "communities and crime" perspective. This approach typically articulates explanation for crime by focusing on the characteristics of communities—a unitary scale most commonly equated with neighborhoods. We argue that this perspective fails to recognize the importance of broader urban geographic contexts, and offer an extension that sees geographically contingent processes functioning at multiple scales simultaneously. We develop this perspective applied to the "spread effects" of public housing on violent crime in surrounding neighborhoods: these spread effects are conditioned by the nature of the urban contexts through which they operate. Specifically, deeply divided and racialized patterns of residential segregation at least partially define the contexts that condition public housing's effect on crime. We examine our perspective using early 1990s block group data for the City of Atlanta and find substantial evidence in support of our perspective. In particular, we find that Techwood Homes, the nation's first federally constructed public housing project, exerted different geographic spread effects in predominantly White than in predominantly Black portions of the city. By failing to recognize the complexity and contingency of public housing's geographic effect on crime in surrounding neighborhoods, previous approaches substantially overestimate crime in White areas, and underestimate crime in Black areas.  相似文献   
49.
地震应急预案是地震应急管理工作的基础和首要环节,应急预案的信息管理系统的开发对该工作的数字化、规范化和信息化十分重要。本文对地震应急预案管理信息系统的研制开发过程进行了技术回顾,介绍了工作思路和技术方案,并简要说明了地震应急预案管理信息系统的功能及使用。  相似文献   
50.
Four critical challenges for physical geography are examined here: deterioration of common cores of knowledge associated with increasing intellectual niche specialization; the need for conceptual thinking and problem‐framing to catch up with measurement and analysis technology; and the need to explicitly incorporate human decision making in analysis of earth surface systems. The future calls for physical geography to embrace and confront the creative tension between nomothetic and interpretive science, and to fruitfully and explicitly integrate these approaches.  相似文献   
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