最新刊期
卷 4 ， 期 11 ， 1999
- 摘要：Traditionally,Geographical Information Systems can only process spatial data in a procedure-oriented way,and the data can' t be treated integrally.This approach greatly limits the development of applications utilizing spatial date.A new and promising method to solve this problem is the spatial structural query language,which extends SQL and provides integrated accessing to spatial data.In this paper,the theory of spatial structural query language is discussed,and a new geographical data model based on the concepts and data model in OGIS is introduced.According to this model,a spatial structural query language—G/SQL is implemented.Through the studies of 9-Intersection Model,G/SQL provided a set of topological relational predicates and spatial functions for GIS application development.The authors have successfully developed a Web-based GIS system—WebGIS—using G/SQL.Experiences show that the spatial operators G/SQL offered are complete and easy-to-use.The BNF representation of G/SQL syntax is included in this paper.关键词：Spatial structural query language;G/SQL;Geographical data model;spatial database3553|192|0更新时间：2024-05-08
- 摘要：Due to the complexity and relativity of image information, it may be present itself problems of vagueness and uncertainty when processing it. Rough sets theory is a new mathematical tool to deal with vagueness and uncertainty. It is a soft computing method and affords intellective information processing useful tool. The paper presents an image preprocessing algorithm that combines human visual properties with rough sets. According to rough sets theory,an image is segmented to different sub images according to condition attribute on human visual properties in the algorithm, and the contrast response of the sub images are transformed respectively. It can realize filtering noise when image enhanced.2420|133|0更新时间：2024-05-08
- 摘要：With the development of science and technology, new remote sensing devices are lunched on schedule. Optical satellite data have been undergone a long time renewal and accumulation. How to reveal hidden information from huge amount of remote sensing data and let it knowledgeable is new challenge for us. In this article, first we analysis the relation between material,structure spectral and remote sensing information, formulate space angel model. Then based on pixel vector and band vector tendency face of multi-band remote sensing information, we analysis the results of“not proper”in the cases of mining some information from remote sensing data when using the software algorithms which are selected according to“the bast optimum”of the statistics. Finally, we illustrate the mathematical principles and effectiveness of algorithms that we used in mining multi-band TM data.2039|149|0更新时间：2024-05-08
- 摘要：An exploratory inductive learning approach is proposed to discover knowledge from spatial database. This approach integrates attribute oriented induction method with exploratory data analysis and Rough set methods. It is flexible and general purpose to discover general knowledge, attribute dependencies and classification knowledge and so on. In order to satisfy the requirements of background knowledge, several methods are proposed for generating concept hierarchies from data. An experiment on agricultural statistical data of China mainland shows that exploratory inductive learning approach is feasible and effective for spatial data mining.2106|157|0更新时间：2024-05-08
- 摘要：Cloud theory is a new theory handling uncertainty based on the uncertain transition between qualitatives and quantitatives. The theory includes cloud model, virtual cloud, cloud operation, cloud transform and uncertainty reasoning. It provides new solutions for many basic problems in data mining and knowledge discovery, such as concept and knowledge representation, transition between qualitatives and quantitatives, concept synthesization and resolution, concept and concept hierarchy generation from data, etc. Cloud model is a model of the uncertain transition between a linguistic term of a qualitative concept and its numerical representation. Cloud model represents a qualitative concept with three digital characteristics, expected value Ex , entropy En and hyper entropy He , which integrate the fuzziness and randomness of a linguistic term in a unified way. This paper presents the fundamentals of cloud theory and its applications in spatial data mining and knowledge discovery, focusing on the cloud models and their algorithms.关键词：Cloud, Cloud model;Virtual clouds;Cloud transform;Spatial data mining and knowledge discovery;Concept hierarchy3993|162|0更新时间：2024-05-08
- 摘要：The article introduces the common tools of Data Mining (DM Tools), which realized the major process of Knowledge Discovery from Database (KDD). The process comprises visual data analysis, data preprocess, data mining, model explain and model evaluation, etc. System structure and module functions of the DM Tools are discussed. Based on the DM Tools, hidden and useful knowledge from long term accumulation, operation database can be mined to support decision making for every profession2811|157|0更新时间：2024-05-08
- 摘要：With the fast development of Internet, it is important for GIS to make it more open. The meaning of conformity for GIS is to change software of GIS in system architecture and data access in order to accord with the requirement of spatial data sharing, integrating and knowledge discovering. This paper puts forward a hierarchy for GIS based on distribute computing platform, which includes four layers those are spatial information display, spatial information service, spatial information access, spatial information storage from top to bottom. Every layer is make up of several functional components. The down layer provides service for up layer. To manage spatial and other information universally, this paper also discusses how to put spatial information into large commercial database which supports geometry type or not directly. Based on the idea of conformity for GIS and knowledge disvovery, this paper also presents an example called GeoBeans.关键词：Network;Conformity;Distribute;Knowledge discovery3352|158|0更新时间：2024-05-08
- 摘要：More and more interest has been paid on Geodata mining and knowledge discovery from large database with the rapid growth of Geodata volume and eagerness for the Geoknowledge. This paper presents a dataset partition model based on information entropy and mutual information. The author argued that the largest information entropy deduction is in accordance with the significant Geodata pattern. With this kernel theoretical base, information entropy based decision tree model and spatial temopral clustering by partition model were developed.2800|133|0更新时间：2024-05-08
- 摘要：Gaussian Mixture Density Modelling and Decomposition (GMDD) is a hierarchical clustering method based on robust statistical theory. Firstly, GMDD is assumed with a mixture group of Gaussian distribution in feature space, then by optimization algorithm the feature which mostly accord with the assumed distribution is hierarchically extracted from space until all of the features in the space are decomposed to a group of featuring pattern. Compared with conventional statistical clustering methods, GMDD's main outstanding superorities are:(1) Initial number of features does not needed to be specified a priori; (2) The proportion of noisy data in the mixture can be large; (3) The parameters estimation of each feature is virtually initial independent; and (4) The variability in the shape and size of the feature densities in the mixture is taken into account. The article presents the model named the GMDD based remote sensing image feature estimation model (GIFEM) , and the model of GA space searching optimization is also presented out.2422|122|0更新时间：2024-05-08
- 摘要：Hyperspectral Data Mining is a key technology to discover spectral information for application of hyperspectral remote sensing data. In this paper, focusing on target recognition and classification, we introduce some hyperspectral data mining algorithm, spectral feature based data mining algorithm, and subpixel spectral information mining algorithm. In advance new algorithms should be developed to explore target spectral information in N dimensional feature space based on spectral knowledge and application modelling.关键词：Hyperspectral;data mining;N dimensioal feature;Target recognition3711|168|0更新时间：2024-05-08
- 摘要：This paper presents the classification of saline soil method，based on knowledge discovery and decision supporting rule base systems using remotely sensed data and GIS The geo science expert thoughts and expe riences to GIS data mining resulied from classificafion。f saline soil and monitoring secondary soil salinization are introduced．In the study，we construeted perfection knowledge discovory rules which are applied to the North China Plain．The resulting rules are used to improve knowledge discovery systera performance．2711|118|0更新时间：2024-05-08
- 摘要：Based on simultaneous measurements of Ku and C bands' radar cross sections (σ0Kuandσ0C) from satellite altimetry, this paper proposes a dual-frequency approach to enhance the performance of existing wind speed algorithms, especially at high wind speeds. A simple scheme ofσ0Ku/σ0Cadjustment is developed, assuming that altimeter measured radar cross sections of Ku and C bands follow a“standard”relationship for various wind speeds under normal conditions. Rain and significant wave height(SWH) induced systematic deviations ofσ0Ku/σ0Cwith respect to their“standard”positions are observed and corrected using the proposed scheme. Validation of our results against buoy observations suggests that the dual-frequency scheme improves the accuracy of altimeter measured sea surface wind speeds by nearly 10% compared to single frequency algorithms.2504|182|0更新时间：2024-05-08
- 摘要：This paper provides a preliminary overview of vegetation green wave change analysis using a time series remote sensing data in China. A series of 12 monthly average NDVI data, which is derived from NOAA AVHRR data is used in this study. The research result shows that the vegetation green wave change is different along the longitude and latitude during the year. Along the same longitude, vegetation change is closely corresponded to the seasonal change law. The higher the latitude is, the greater the scope of seasonal changes. Along the same latitude the vegetation index change is closely related to precipitation change during the year. The result of greenness classification for each monthly NDVI image also shows that in summer, the high green wave classes occupy most area of China; in opposite, brown wave classes occupy most of territory of China in winter.关键词：Vegetation;Green wave;NOAA data3067|201|0更新时间：2024-05-08
- 摘要：Built on the global network infrastructure, Digital Earth embeds multi-source mass storage of data into the universal spatial/temporal architecture. Digital Earth is oriented to excavation and utilization of information resources in depth/width, and is expected to initiate the construction of the next-generation global information infrastructure (NGII). Development of the digital earth follows an evolutionary process, and constructing the“spatial information infrastructure”is a starting point of the process. Beyond the“Desktop”metaphor of the current information platform, the digital earth will form a natural, immersible information environment. As a guiding goal, the digital earth can be found its applications in almost every field. The technical innovations aroused during development of the digital earth will incessantly promote form of new technical industries and new service industries.关键词：Digital Earth, Spatial information infrastructure, Share and interoperability, GeoAgent,4022|129|0更新时间：2024-05-08
- 摘要：Digital Earth calls for the sharing of spatial information, spatial data warehouse (SDW) is a convenient way for managing and distributing information among public. In this paper, the society and institutional context of building spatial data warehouse is given, that is followed by the discussing of strategies used when constructing SDW and architecture of SDW. Then related construction steps of SDW are introduced in detail. Based on these theories discussed, a prototype of SDW is designed and implemented to display how to build a SDW.3550|202|0更新时间：2024-05-08
- 摘要：Increasing application of Geospatial information requires integration, fusion and interoperability of current monolithic GIS, especially of more complex and multidisciplinary application. Interoperability is the base for information integration and fusion. A five level GIS interoperability model is given. The spatial information infrastructure (SII) provides a sharing spatial information framework, architecture and an interoperability platform for geographical information system. This paper studies architecture of spatial information infrastructure, and gives the relationship between GIS interoperability model and spatial information infrastructure architecture. We consider GIS interoperability model provides theory base for SII, and SII provides an implementation platform for GIS interoperability model.2262|125|0更新时间：2024-05-08
- 摘要：Metadata is one of key technology of constructing Digital Earth, and a main solution of implementing spatial information sharing in Digital Earth. In this paper, the definition, important role in Digital Earth, content, management model and its solutions, and application of Metadata have been researched in detail. And based on one of solutions, demonstration system of management model of Metadata have been achieved, and introduced here. It provides a feasible and practical way to spatial information sharing in Digital Earth.关键词：Digital earth;Spatial information sharing;Spatial Metadata;Spatial data clearinghouse2516|128|0更新时间：2024-05-08
- 摘要：Digital Earth is an adaptive network system which has characteristics of complexity and dynamic change.By comparing the human reaction to the stimulation from outside with the behavior of the Digital Earth.GeoAgent,an intelligent entity which has capabilities of learning and geospatial\|processing is proposed to act as the basic processing unit in the adaptive network system of the Digital Earth.Furthermore,an adaptive network system model of the Digital Earth based on GeoAgent is brought forward.关键词：Digital earth;GeoAgent;neural network;Neuron2732|123|0更新时间：2024-05-08
- 摘要：Digital mini\|area is the microcosmic description and reification of the digital earth and can be simply defined as a digital and virtual small area in concept. Based on the theory and strategy of Digital Earth, the concept of Digital Mini\|area is proposed. To develop and establish a digital mini\|area with the related technologies of the digital earth and such technologies as three\|in\|one integrative network system, intelligent mini\|area, intelligent house system and digital neural system, the general structure, the physical infrastructure, the network structure, the information structure, the function structure, the model structure, the key technologies and the integrative applications of Digital Mini\|area are then discussed. At the end, some methods and guidelines on how to develop the digital mini\|area are also given out.2118|112|0更新时间：2024-05-08
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