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991.
The spatial division of industries of the pearl river delta in the 1990s: Characteristics and trends
The article analyzed the spatial division of industries of the Pearl River Delta (PRD) in the 1990s, a period that witnessed
the deepening of the reform and opening policies and continued rapid development of the region. By adopting the index of specialization,
the extent of specialization, its change and its spatial distribution in the region are measured and demonstrated. The research
revealed that, despite the trend of more balanced development of the secondary sector between the PRD and the rest of the
province, in the PRD, it is the unbalanced development that dominated and the spatial division of the secondary sector has
been shaped. The tertiary industry has also been experiencing unbalance development and the spatial division of the tertiary
sector has been emerging, its extent of concentration appearing even more evident than that of the secondary sector. The author
also discussed the linkage between the spatial division of the two sectors. In the end of the paper, the trends of the spatial
division of the industries in the PRD are forecasted.
Foundation item: Under the auspices of the National Natural Science Foundation of China (No. 49831030).
Biography: XU Yong-jian (1972 – ), female, a native of Changsha City, Ph. D.. Her research interest includes urban geography. 相似文献
992.
《The Professional geographer》1986,38(4):425-430
Geographic Software Reviewed in this article: LIFE TABLES and the LESLIE MATRIX. CONDUIT MENTMAP2 . Lawrence W. Carstensen Jr . PC-MATLAB , Version 1.0. The Math Works, Inc. QUICKMAP , version 1.0. Sammamish Data Systems, Inc. SYSTAT: THE SYSTEM FOR STATISTICS , Version 2.1, Systat Inc. USA DISPLAY . Instant Tecall 相似文献
993.
S. Heynisch A. Pekdeger B. Richter M. -Th. Schafmeister W. Skala 《Mathematical Geology》1994,26(4):505-517
Computer-based risk evaluation methods are practical tools to compare automatically and evaluate contaminated sites. HYDRISK is an example of adequate knowledge-based systems: HYDRISK evaluates hydrogeological properties and chemical criteria relevant to contaminant transport with respect to the necessary remedial actions. It works at a high investigative level and enables geologists and engineers to draw differentiated conclusions for selecting remediation methods for the contaminated site. HYDRISK emphasizes space and time dependent aspects of the contaminant transport. It is supported by a geographic information system (GIS) to display the evaluation results. Some ideas on considering the spatiotemporal variability of relevant parameters by means of geostatistical methods and numerical models will be given. 相似文献
994.
A. J. Desbarats 《Mathematical Geology》1994,26(1):1-21
Steady-state radial flow in three-dimensional heterogeneous media is investigated using a geostatistical approach. The goal of the study is to develop a model of the relationship between corescale hydraulic conductivities measured at the wellbore and the conductivity of the surrounding drainage region as measured by a larger scale flow experiment such as a pump test. Conductivity at the point or core-scale is modeled as a stationary and multivariate lognormal spatial random function. Conductivity of the drainage region is obtained by a weighted nonlinear spatial average over the point-scale values within. This empirical spatial averaging process is shown to yield excellent approximations of true effective drainage region conductivities calculated using a numerical flow model. The geostatistical model for point-scale conductivity and the spatial averaging process are used to determine the first and second order ensemble moments of drainage region conductivity. In particular, an expression is derived for the conditional expectation of drainage region conductivity given point-scale values measured at the wellbore. The results are illustrated in a case study of a well from a sandstone oil reservoir where both core and transient-test conductivity data from the same interval are available for comparison. 相似文献
995.
996.
Fractal geostatistics are being applied to subsurface geological data as a way of predicting the spatial distribution of hydrocarbon reservoir properties. The fractal dimension is the controlling parameter in stochastic methods to produce random fields of porosity and permeability. Rescaled range (R/S)analysis has become a popular way of estimating the fractal dimension, via determination of the Hurst exponent (H). A systematic investigation has been undertaken of the bias to be expected due to a range of factors commonly inherent in borehole data, particularly downhole wireline logs. The results are integrated with a review of previous work in this area. Small datasets. overlapping samples, drift and nonstationariry of means can produce a very large bias, and convergence of estimates of H around 0.85–0.90 regardless of original fractal dimension. Nonstationarity can also account for H>1, which has been reported in the literature but which is theoretically impossible for fractal time series. These results call into question the validity of fractal stochastic models built using fractal dimensions estimated with the R/Smethod. 相似文献
997.
Dae S. Young 《Mathematical Geology》1987,19(6):467-479
Geostatistics is extended to the spatial analysis of vector variables by defining the estimation variance and vector variogram in terms of the magnitude of difference vectors. Many random variables in geotechnology are in vectorial terms rather than scalars, and its structural analysis requires those sample variable interpolations to construct and characterize structural models. A better local estimator will result in greater quality of input models; geostatistics can provide such estimators: kriging estimators. The efficiency of geostatistics for vector variables is demonstrated in a case study of rock joint orientations in geological formations. The positive cross-validation encourages application of geostatistics to spatial analysis of random vectors in geoscience as well as various geotechnical fields including optimum site characterization, rock mechanics for mining and civil structures, cavability analysis of block cavings, petroleum engineering, and hydrologic and hydraulic modelings. 相似文献
998.
Indicator cokriging is an alternative to disjunctive kriging for estimation of spatial distributions. One way to determine which of these techniques is more accurate for estimation of spatial distributions is to apply each to a particular type of data. A procedure is developed for evaluation of disjunctive kriging and indicator cokriging for such an application. Application of this procedure to earthquake ground motion data found disjunctive kriging to be at least as accurate as indicator cokriging for estimation of spatial distributions of peak horizontal acceleration. Indicator cokriging was superior for all other types of earthquake ground motion data. 相似文献
999.
Xinxian Lu 《中国地理科学(英文版)》1992,2(3):256-265
The developed regions are faced with the problems of regional comprehensive development, and the research on regional comprehensive
development has become a trend in the world. To optimize regional industrial structure and to select and determine scientifically
the spatial development strategy of regional industries are the central themes to be solved for the research on regional comprehensive
development in the developed regions. This paper proposed the basis for optimizing regional industrial structure, and the
main factors of selecting and determining the regional leading industries. Based on this, the paper puts forward the leading
industries and the spatial development strategy in Shanghai-Nanjing-Hangzhou area in the future ten or more years. Combined
with the situation of Shanghai-Nanjing-Hangzhou area, the paper also discusses some problems of locating superior developing
axis to benefit the rational distribution of regional productive forces. 相似文献
1000.
Ni Xiang-bin 《Chinese Astronomy and Astrophysics》1988,12(4):320-323
We think that a steady material exchange in the upper solar atmosphere can act as a heat engine that cools the corona and heats the corona-chromosphere transition region. We have considered heat conduction from the corona and radiation loss in the transition region and have calculated the temperature, density and velocity distributions in the transition region. Also discussed is the relation between the material flux, the velocity boundary value and the thickness of the transition region. 相似文献