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1.
 A potential-type Molodensky telluroid based upon a minimum-distance mapping is derived. With respect to a reference potential of Somigliana–Pizzetti type which relates to the World Geodetic Datum 2000, it is shown that a point-wise minimum-distance mapping of the topographical surface of the Earth onto the telluroid surface, constrained to the gauge W(P)=u(p), leads to a system of four nonlinear normal equations. These normal equations are solved by a fast Newton–Raphson iteration. Received: 7 February 2000 / Accepted: 23 October 2001  相似文献   

2.
The paper presents results of applied medical-geographic mapping work by the Uzbek SSR Academy of Sciences in support of public health studies in Central Asian areas where water supplies are contaminated by runoff from irrigated fields. The final product of the work is a map depicting surface water quality in aggregate terms and according to indices for specific pollutants (for water quality monitoring points), which is described both in terms of its content and methods of data compilation and transformation. Translated by Elliott B. Urdang, Providence, RI 02906 from: Izvestiya vysshikh uchebnykh zavedeniy: Geodeziya i aerofotos “yemka, 1989, No. 2, pp. 166–171.  相似文献   

3.
This paper demonstrates how ice-surface relief identified on space imagery can be used in mapping selected elements of the geologic structure of the Antarctic Peninsula. The mapping procedure is based on the fact that all major subglacial relief forms appear, albeit in subdued form, on the surface of slow moving and relatively thin ice sheets. Since subglacial bedrock relief reflects geologic structure, particular surface configurations of ice identified on space imagery can be used as indicators of major structural elements. Examples of the procedure, including imagery of ice relief and corresponding cartographic representations of underlying structure are provided for faults and ring structures. Translated from: Antarktika, AN SSSR Mezhduvedomstvennaya komissiya po izucheniyu Antarktiki, Doklady komissii [USSR Academy of Sciences Joint Commission on Antarctic Research, Commission Report], No. 24. Moscow, 1985, pp. 50-55. An article demonstrating the application of these methods in the compilation of a geologic map for a part of the Antarctic Peninsula will appear in a later issue.  相似文献   

4.
Salinization is one of the major soil degradation threats occurring worldwide. This study evaluates the feasibility of operational surface soil salinity mapping based on state-of-the-art Earth Observation (EO) products captured by sensors on-board WorldView-2 (WV2) and Landsat 8 satellites. The proposed methods are tested in Timpaki, south-central Crete,Greece, where brackish water irrigation puts soil health at risk of soil salinization. In all cases, EO products are calibrated against soil samples collected from bare soil locations. Results indicate a moderate correlation of observed ECe values with the investigated remote sensing parameters. Regarding sensitivity to saline soil, the yellow band displays higher values. Comparison between methods used in the literature shows that those developed specifically for soil salinity, and especially index S5, perform better. The proposed ‘detection index’ and 3D PCA transformation methodology perform reasonably well in detecting areas with high ECe values and provide a simple and effective operational alternative for saline topsoil detection and mapping.  相似文献   

5.
The basic methodology of structural-landscape mapping is outlined: (a) preliminary delineation, using remote sensing imagery, of macroregions where surface topography corresponds generally to underlying geologic structure; and (b) identification and mapping (at smaller scales) of landscape anomalies within these regions which indicate structural-tectonic disturbances of a particular type (oil-gas traps, for example). Various types of structural-landscape maps are then compared for the purpose of demonstrating both the multiplicity of uses for such maps and the importance of carefully selecting indices for mapping and optimal designs for specific uses, such as oil and gas exploration. Translated from: Izvestiya, Vsesoyuznoye Geograficheskoye Obshchestvo, 1984, No. 3, pp. 218-224.  相似文献   

6.
A brief history of land-use mapping sets the stage for a survey of contemporary land-use mapping across the world, and more specifically, the applications of remote sensing methods in such mapping. Other issues addressed include the need to refine the definition of land use to encompass the totality of geographic space, to formally recognize the difference between large-scale maps of agricultural land-use and smaller-scale general land-use maps, and to investigate more closely the wisdom and desirability of a standardized world land-use classification. Four types of land-use maps are identified: diagnostic/informational, historical, dynamic, and predictive. Translated from: Vestnik Leningradskogo Universiteta, 1983, No. 24, pp. 52-61.  相似文献   

7.
8.
The authors describe how cartographic research methods can be integrated with geographic information systems and automated mapping systems for the purpose of monitoring and analyzing negative impacts of agricultural and food processing activities on the environment. The paper also outlines basic research trends in ecological-geographical mapping and the content and types of cartographic products derived from mapping environmental impacts of the agroindustrial complex. A final section focuses on principles for the mapping of specific aspects and/or consequences of agroindustrial activity, e.g., soil erosion, agricultural chemical concentrations, water conservation issues. Translated by Edward Torrey, Alexandria, VA 22308 from: Geografiya i prirodnyye resursy, 1991, No. 3, pp. 5–11.  相似文献   

9.
The author, in a review of papers presented at the First All-Union Conference on the Geography and Mapping of the Oceans, outlines the present status and current trends of marine cartography in the USSR. Issues warranting increased attention include development of a systems approach for the mapping of marine ecosystems; improvement of methods and principles for the mapping of coastal zones, bottom relief, and shelf topography; and accelerated production of economic/resource maps of the oceans. Work now underway on a comprehensive, multi-volume A tlas of the Oceans reflects a Soviet concern with these issues. Translated from: Geodeziya i kartografiya, 1984, No. 12, pp. 38-42.  相似文献   

10.
We present new methods for analyzing geo-referenced statistical data. These methods combine visualization and direct manipulation techniques of exploratory data analysis and algorithms for data mining. The methods have been implemented by integrating two hitherto separate software tools: Descartes for interactive thematic mapping, and the data mining toolbox Kepler. In using these tools, data analysis may proceed as a steady interaction between visual inspiration and insights gained from mathematical–statistical calculations. After introducing the various components of the methods and tools, the paper guides the reader through in-depth examples of using the tools in the context of analysis of urban demographic data. In particular, it is shown how geography-based classifications of urban districts can be related to available thematic characteristics by applying the data mining algorithms classification tree derivation, attribute weighting, and subgroup discovery.  相似文献   

11.
Scientific understanding, technology, and social, economic, and environmental conditions have driven a rapidly changing demand for geographic information, both digital and analog. For more than a decade, the U.S. Geological Survey (USGS) has been developing innovative partnerships with other government agencies and private industry to produce and distribute geographic information efficiently; increase activities in remote sensing to ensure ongoing monitoring of the land surface; and develop new understanding of the causes and consequences of land surface change. These activities are now contributing to a more robust set of geographic information called The National Map (TNM). The National Map is designed to provide an up-to-date, seamless, horizontally and vertically integrated set of basic digital geographic data, a frequent monitoring of changes on the land surface, and an understanding of the condition of the Earth's surface and many of the processes that shape it. The USGS has reorganized its National Mapping Program into three programs to address the continuum of scientific activities—describing (mapping), monitoring, understanding, modeling, and predicting. The Cooperative Topographic Mapping Program focuses primarily on the mapping and revision aspects of TNM. The National Map also includes results from the Land Remote Sensing and Geographic Analysis and Monitoring Programs that provide continual updates, new insights, and analytical tools. The National Map is valuable as a framework for current research, management, and operational activities. It also provides a critical framework for the development of distributed, spatially enabled decision support systems.  相似文献   

12.
Vegetation type is an environmental attribute that varies across the landscape and over time. Its continuous assessment is important for monitoring land use changes and forest degradation. There are advanced methods that can estimate the fractional cover of vegetation types within each pixel. This paper compares some methods for subpixel mapping of forest cover in the state of San Luis Potosí, Mexico, using Moderate Resolution Imaging Spectroradiometer (MODIS)-derived spectral data (MCD43A4). Three methods were tested: (1) Bayesian posterior probability, (2) the Fuzzy k nearest neighbor (FkNN), and (3) linear spectral mixture analysis (LSMA). While the Bayesian approach gave the poorest correlations, FkNN (r = 0.78) and LSMA (r = 0.81) estimations were successfully validated with information obtained from a Landsat image. This paper represents an interesting attempt to compare rarely reported FkNN with traditional approaches such as LSMA and the Bayesian one.  相似文献   

13.
General principles underlying the study of spatial inequality are outlined from a Soviet perspective before more specific coverage of guidelines for its portrayal in cartographic form. Questions addressed in the development of a center-periphery model for isarithmic mapping of socioeconomic differences in Hungary include selection of appropriate indices and samplings of data points for mapping, and methods for data normalization and comparison. Examples of both aggregate and more narrowly focused maps of living conditions are included. Translated from: Vestnik Moskovskogo Universiteta, geografiya, 1985, No. 4, pp. 68-74.  相似文献   

14.
Over the last decade the analysis of Earth observation data has evolved from what were predominantly per-pixel multispectral-based approaches, to the development and application of multiscale object-based methods. To empower users with these emerging object-based approaches, methods need to be intuitive, easy to use, require little user intervention, and provide results closely matching those generated by human interpreters. In an attempt to facilitate this, we present multiscale object-specific segmentation (MOSS) as an integrative object-based approach for automatically delineating image-objects (i.e., segments) at multiple scales from a high-spatial resolution remotely sensed forest scene. We further illustrate that these segments cognitively correspond to individual tree crowns, ranging up to forest stands, and describe how such a tool may be used in computer-assisted forest inventory mapping. MOSS is composed of three primary components: object-specific analysis (OSA), object-specific upscaling (OSU), and a new segmentation algorithm referred to as size constrained region merging (SCRM). The rationale for integrating these methods is that the first two provide the third with object-size parameters that otherwise would need to be specified by a user. Analysis is performed on an IKONOS-2 panchromatic image that represents a highly fragmented forested landscape in the Sooke Watershed on southern Vancouver Island, BC, Canada.  相似文献   

15.
The paper describes a program for the complex (comprehensive) automated mapping of Moscow Oblast, performed jointly by various departments within the Moscow University Geography Faculty. The program was instituted during the Eleventh Five-Year Plan (1981-1985) and includes among its objectives: (1) support for local economic management and planning; (2) promotion of basic research in automated cartographic and geographic information systems; and (3) the improvement of methods of complex mapping. A number of maps compiled to date are described, and sample maps produced by the Moscow University Automated Mapping System are presented. Translated from: Vestnik Moskovskogo Universiteta, geografiya, 1988, No. 1, pp. 54-59 by Jay K. Mitchell; PlanEcon, Inc.; Washington, DC 20005.  相似文献   

16.
The author reviews the contributions of the “aerospace” disciplines (remote sensing, photogrammetry, photometry) in the training of cartographers at Moscow University. Changes in the present curriculum are advocated, leading to the emergence of a unified educational discipline referred to alternately as “remote mapping methods,” or “remote sensing and mapping.” Training in this discipline is designed to enhance the interpretation and map compilation skills of cartographers working with space imagery. Translated from: Vestnik Moskovskogo Universiteta, geografiya, 1984, No. 5, pp. 40-43.  相似文献   

17.
The paper surveys the development of “space geography”–a field of knowledge applying the methods of remote sensing, the physical sciences, and mathematics in the solution of geographic problems. Early advances featured methodological improvements (use of quantitative methods in image processing), whereas future research must focus upon perfecting our knowledge of: (a) relationships underlying the use of these methods, i.e., between environmental parameters and reflectance values, (b) methods of effectively combining different types of imagery, and image products and field work, in research, and (c) appropriate quantitative indices for feature recognition. Examples of the operationalization of such concerns are demonstrated for land-use and soil mapping projects. Translated from: Izvestiya, AN SSSR, seriya geograficheskaya, 1985, No. 5, pp. 110–116.  相似文献   

18.
A Russian geographer summarizes the results of a comprehensive study of modern landscapes and the mapping of diverse ecological situations. The procedure involves the development of a system of criteria and indices for the assessment of the properties of the environment, which provide a sound basis for comprehensive ecological mapping. The importance of an ecological assessment in the mapping of environmental problems and situations in support of the stable and balanced development of regions is demonstrated. Translated by Edward Torrey, Alexandria, VA from: Izvestiya Akademiya Nauk, seriya geograficheskaya, 1999, No. 1, pp. 81-87.  相似文献   

19.
A team of Russian geographers describes the development of a program for mapping land use/resource development and the condition of the environment in Russia's Buryat Republic. Three ecological maps recently compiled in the Republic, using a single cartographic base and employing standardized methods, are described. The last such map is a map of environmental use that reflects both a resource-development and an environmental-protection perspective. The article includes detailed examples of the legend of the latter map. Translated by Edward Torrey, Alexandria, VA from: Geografiya i prirodnyye resursy, 1998, No. 3, pp. 23-29.  相似文献   

20.
A spectral linear-mixing model using Landsat ETM+ imagery was undertaken to estimate fraction images of green vegetation, soil and shade in an indigenous land area in the state of Mato Grosso in the central-western region of Brazil. The fraction images were used to classify different types of land use and vegetation cover. The fraction images were classified by the following two methods: (a) application of a segmentation based on the region-growing technique; and (b) grouping of the regions segmented using the per-region unsupervised classifier named ISOSEG. Adopting a 75% threshold, ISOSEG generated 44 clusters that were grouped into eight land-use and vegetation-cover classes. The mapping achieved an average accuracy of 83%, showing that the methodology is efficient in mapping areas of great land-use and vegetation-cover diversity, such as that found in the Brazilian cerrado (savanna).  相似文献   

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