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1.
Aimed at promoting regional coalitions and expanding the approach to economic links, this paper puts forward some new concepts
such as link intensity and receiving coefficient, expounds the indexes of quantitative analysis of economic links and establishes
the quantitative-analysis model of economic links. With help of the model, this paper calculates the values of the link intensities
between Su-Xi-Chang (Suzhou-Wuxi-Changzhou) region and Shanghai, and analyzes the regional difference of the economic links. 相似文献
2.
沿海地区城市发展及地面沉降的系统控制 总被引:9,自引:0,他引:9
郑铣鑫 《海洋地质与第四纪地质》1992,12(1):57-65
本文运用系统工程原理,系统论述了地下水合理开发、管理和地面沉降系统控制,这对沿海地区地面沉降控制起到重要的作用。 相似文献
3.
4.
5.
基于GIS的区域经济统计分析系统的设计与实现 总被引:1,自引:0,他引:1
随着经济的发展,区域间经济相互作用和影响的关系越来越密切,忽略空间相互作用的传统区域经济分析手段和方法开始显现出一些明显的不足。而GIS在处理和分析区域地理数据上具有强大的空间分析能力,为此我们引入GIS工具对区域经济进行分析,相较于传统的分析手法有了很大改善。本文以江西省区域经济数据为例,设计了一个基于GIS的区域经济统计分析系统,并利用Arcob-jects二次开发控件结合VB可视化编程语言,实现了大部分区域经济统计分析功能,最后并将结果进行网络发布。研究结果表明将GIS引入到区域经济统计分析中,更能正确、有效的揭示区域经济发展在空间上的联系,为区域经济研究决策提供服务。 相似文献
6.
A. McGarr 《Pure and Applied Geophysics》1994,142(3-4):467-489
Although laboratory stick-slip friction experiments have long been regarded as analogs to natural crustal earthquakes, the potential use of laboratory results for understanding the earthquake source mechanism has not been fully exploited because of essential difficulties in relating seismographic data to measurements made in the controlled laboratory environment. Mining-induced earthquakes, however, provide a means of calibrating the seismic data in terms of laboratory results because, in contrast to natural earthquakes, the causative forces as well as the hypocentral conditions are known. A comparison of stick-slip friction events in a large granite sample with mining-induced earthquakes in South Africa and Canada indicates both similarities and differences between the two phenomena. The physics of unstable fault slip appears to be largely the same for both types of events. For example, both laboratory and mining-induced earthquakes have very low seismic efficiencies
where
a
is the apparent stress and
is the average stress acting on the fault plane to cause slip; nearly all of the energy released by faulting is consumed in overcoming friction. In more detail, the mining-induced earthquakes differ from the laboratory events in the behavior of as a function of seismic momentM
0. Whereas for the laboratory events 0.06 independent ofM
0, depends quite strongly onM
0 for each set of induced earthquakes, with 0.06 serving, apparently, as an upper bound. It seems most likely that this observed scaling difference is due to variations in slip distribution over the fault plane. In the laboratory, a stick-slip event entails homogeneous slip over a fault of fixed area. For each set of induced earthquakes, the fault area appears to be approximately fixed but the slip is inhomogeneous due presumably to barriers (zones of no slip) distributed over the fault plane; at constant
, larger events correspond to larger
a
as a consequence of fewer barriers to slip. If the inequality
a
/
0.06 has general validity, then measurements of
a
=µE
a
/M
0, where is the modulus of rigidity andE
a
is the seismically-radiated energy, can be used to infer the absolute level of deviatoric stress at the hypocenter. 相似文献
7.
Analyzing the tables and probability maps posted by Yan Y. Kagan and David D. Jackson in April 2002–September 2004 at http://scec.ess.ucla.edu/~ykagan/predictions_index.html and the catalog of earthquakes for the same period, the conclusion is drawn that the underlying method could be used for prediction of aftershocks, while it does not outscore random guessing when main shocks are considered. 相似文献
8.
9.
Andrew Sluyter 《Geographical review》2006,96(3):361-381
ABSTRACT. While in New Spain from 1803 to 1804, Alexander von Humboldt interacted with some of its landscapes and the texts that represented them. Analysis of those interactions regarding the Basin of Mexico and the Gulf lowlands demonstrates what purely text‐based studies of the production of places cannot: The contrasting landscape elements and patterns that had emerged over millennia during precolonial times in those two places, their relative degrees of depopulation during the colonial era, and the relative degrees of rigor Humboldt applied to interacting with the resulting landscapes and the texts that represented them greatly affected his representations of those places in his 1811 Essai politique sur le royaume de la Nouvelle‐Espagne. His representations of the precolonial Basin of Mexico as productively developed and of the precolonial Gulf lowlands as pristine have influenced the transformations of those places in the two centuries after New Spain became the Mexican republic through its wars of independence (1810–1821). 相似文献
10.
A. Ankilov A. Baklanov M. Colhoun K. -H. Enderle J. Gras Yu. Julanov D. Kaller A. Lindner A. A. Lushnikov R. Mavliev F. McGovern T. C. O'Connor J. Podzimek O. Preining G. P. Reischl R. Rudolf G. J. Sem W. W. Szymanski A. E. Vrtala P. E. Wagner W. Winklmayr V. Zagaynov 《Atmospheric Research》2002,62(3-4)
During an international workshop at the Institute for Experimental Physics of the University of Vienna, Austria, which was coordinated within the Committee on Nucleation and Atmospheric Aerosols (IAMAS-IUGG), 10 instruments for aerosol number concentration measurement were studied, covering a wide range of methods based on various different measuring principles. In order to investigate the detection limits of the instruments considered with respect to particle size, simultaneous number concentration measurements were performed for monodispersed aerosols with particle sizes ranging from 1.5 to 50 nm diameter and various compositions.The instruments considered show quite different response characteristics, apparently related to the different vapors used in the various counters to enlarge the particles to an optically detectable size. A strong dependence of the 50% cutoff diameter on the particle composition in correlation with the type of vapor used in the specific instrument was found. An enhanced detection efficiency for ultrafine hygroscopic sodium chloride aerosols was observed with water operated systems, an analogous trend was found for n-butanol operated systems with nonhygroscopic silver and tungsten oxide particles. 相似文献