Simulated annealing for earthquake location   总被引：1，自引：0，他引：1  

Stephen D. Billings 《Geophysical Journal International》1994,118(3):680-692

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从经济地理学角度对区域经济学理论体系的理解   总被引：5，自引：1，他引：5  

樊杰 《地理研究》1997,16(1):39-44

从区域经济学的内容结构出发,重点对传统区位论、空间结构理论和区域发展理论等理论体系问题进行了探讨。就主要理论研究范畴和它们之间的区别、在我国目前的应用问题、以及经济地理学同区域经济学的学科建设关系等阐述了基本观点。  相似文献   

跨国公司的组织模式与区位选择     

熊世伟  宁越敏 《世界地理研究》1997,(1)

本文在讨论价值链的基础上构建了一个用于解释跨国公司组织结构和区位模式的理论框架。根据跨国公司对外直接投资的区位战略，将跨国公司的投资动机划分为三类：资源导向型、降低成本导向型、市场驱使型。然后，分析了跨国公司的组织结构，并按跨国公司业务国际化的特点将跨国公司管理结构划分为七种类型：国际分工型、世界区域化型、国家子公司、世界范围生产型、世界范围功能型、母质型和母质复合型、混合型。  相似文献   

加拿大城市住户居住选址行为研究──以多伦多都市普查区和蒙特利尔都市普查区为例   总被引：3，自引：0，他引：3  

杜德斌 《世界地理研究》1997,(1)

本文以多伦多都市普查区和蒙特别尔都市普查区为研究区域，通过剖析城市地域内部五个圈层（CBD、内城区、成熟郊区、新郊区和远郊区）居住人口的分布现状，分析不同社会经济阶层的住户居住选址的基本倾向，考察居住选址行为与住宅类型的空间分布和居住区位要素制约关系。分析表明：中等经济收入和文化程度、有未成年子女的家庭倾向于居住在城市边缘地区；经济收入、文化程度较低和较高的青年单身、无子女夫妻住户和老年住户倾向于居住在城市中心区；城市内部的居住迁移主要迁往城市外围地区，外来居民（包括国内和国外）倾向集居在城市中心区。居住选址行为是受住宅空间分布差异和居住区位条件的交互制约。一定社会经济结构的住户是从各类住宅和居住区位的各种构成要素的优化配置中选择居住定位。  相似文献   

P^—波定位方法的研究及软件编制   总被引：2，自引：0，他引：2  

潘科  肖立萍 《东北地震研究》1997,13(1):69-76

Ｐ＾－波定位方法是针对网内及网缘发生较大震级地震时，地震波记录限幅Ｓ＾＝难以辨认的情况，而编；与的单震相定位程序。该程序可由数字化仪输入地震波到时数据，然后进行定位，定位计算分两步进行，即初定和修定，初定仅根据区域台风提供直达波到时，列出走时方程，将走时方程线性化，解出四个震源参数，为了防止输入的个别错误数据影响定位，采取了图形显示的方法。  相似文献   

Body Wave Traveltimes and A Spherically Symmetric P- and S-Wave Velocity Model   总被引：2，自引：0，他引：2  

Andrea Morelli  Adam M. Dziewonski 《Geophysical Journal International》1993,112(2):178-194

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Improvements in mining induced microseismic source locations at the Lucky Friday mine using an automated whole-waveform analysis system     

Douglas A. Dodge  Kenneth F. Sprenke 《Pure and Applied Geophysics》1992,139(3-4):609-626

For years, severe rockburst problems at the Lucky Friday mine in northern Idaho have been a persistent safety hazard and an impediment to production. An MP250 based microseismic monitoring system, which uses simple voltage threshold picking of first arrivals, has been used in this mine since 1973 to provide source locations and energy estimates of seismic events. Recently, interest has been expressed in developing a whole waveform microseismic monitoring system for the mine to provide more accurate source locations and information about source characteristics. For this study, we have developed a prototype whole-waveform microseismic monitoring system based on a 80386 computer equipped with a 50 kHz analog-digital convertor board. The software developed includes a data collection program, a data analysis program, and an event detection program. Whole-waveform data collected and analyzed using this system during a three-day test have been employed to investigate sources of error in the hypocenter location process and to develop an automatic phase picker appropriate for microseismic events.Comparison of hypocenter estimates produced by the MP250 system to those produced by the whole-waveform system shows that significant timing errors are common in the MP250 system and that these errors caused a large part of the scatter evident in the daily activity plots produced at the mine. Simulations and analysis of blast data show that analytical control over the solutions is strongly influenced by the array geometry. Within the geophone array, large errors in the velocity model or moderate timing errors may result in small changes in the solution, but outside the array, the solution is very sensitive to small changes in the data.Our whole-waveform detection program picks event onset times and determines event durations by analysis of a segmented envelope function (SEF) derived from the microseismic signal. The detection program has been tested by comparing its arrival time picks to those generated by human analysis of the data set. The program picked 87% of the channels that were picked by hand with a standard error of 0.75 milliseconds. Source locations calculated using times provided by our entire waveform detection program were similar to those calculated using hand-picked arrival times. In particular, they show far less scatter than source locations calculated using arrival times based on simple voltage threshold picking of first arrivals.  相似文献   

Identification ofP/S-wave successions for application in microseismicity     

J. -P. Deflandre  M. Dubesset 《Pure and Applied Geophysics》1992,139(3-4):405-420

Interpretation ofP/S-wave successions is used in induced or passive microseismicity. It makes the location of microseismic events possible when the triangulation technique cannot be used. To improve the reliability of the method, we propose a technique that identifies theP/S-wave successions among recorded wave successions. A polarization software is used to verify the orthogonality between theP andS polarization axes. The polarization parameters are computed all along the 3-component acoustic signal. Then the algorithm detects time windows within which the signal polarization axis is perpendicular to the polarization axis of the wave in the reference time window (representative of theP wave). The technique is demonstrated for a synthetic event, and three application cases are presented. The first one corresponds to a calibration shot within which the arrivals of perpendicularly polarized waves are correctly detected in spite of their moderate amplitude. The second example presents a microseismic event recorded during gas withdrawal from an underground gas storage reservoir. The last example is chosen as a counter-example, concerning a microseismic event recorded during a hydraulic fracturing job. The detection algorithm reveals that, in this case, the wave succession does not correspond to aP/S one. This implies that such an event must not be located by the method based on the interpretation of aP/S-wave succession as no such a succession is confirmed.  相似文献   

城市军事地理系统与空间结构     

刘晓静 《测绘学院学报》1992,(1)

本文在讨论现代城市军事作用的基础上,运用系统论和区位论的方法探讨建立城市军事地理系统和城市军事地理空间结构的有关理论。  相似文献   

区位能研究     

周杰文  范斌  丰志勇  胡文静 《地理与地理信息科学》2005,21(6):108-111

区位、区位选择和区位优势分析的基础是该文中提出的区位能,即分析各极点因其区位条件 而对区位能客体的吸引力.通过考察极点自身的属性和因极点位于某一区域而具有的该区域 内的属性,并设立一定的程序来确定不同目的类型极点的理论区位能、可置信区位能和可实践区位能.区域的各种区位能由其内各类极点的相应区位能组成.  相似文献