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Fuzziness is an internal property of spatial objects.How to model fuzziness of a spatial object is a main task of next generation GIS.This paper proposes basic fuzzy spatial object types based on fuzzy topology.These object types are the natural extension of current nonfuzzy spatial object types.A fuzzy cell complex structure is defined for modeling fuzzy regions,lines and points.Furthermore,fuzzy topological relations between these fuzzy spatial objects are formalized based on the 9intersection approach.This model can be implemented for GIS applications due to its scientific theory basis. 相似文献
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To design retrieval algorithm of spatial relations for spatial objects with randomness in GIS, this paper builds up the membership functions based on set theory idea, used for determination of topological spatial relations between random objects, such as between point and point, point and line or polygon, which provides theoretical basis for retrieving spatial relations between certain and random objects. Finally, this paper interprets detailed methods and steps of realizing them by means of some simple examples under the GIS's environment. 相似文献
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DENG MinLI ChengmingLIU Wenbao 《地球空间信息科学学报》2001,4(4):43-48
1 IntroductionSpatialrelationsqueryisoneofbasicfunctionsinGIS’sapplication .MostofcurrentcommercialGISscanonlyqueryspatialrelationsforspatialob jectswithoutanyerrororuncertainty ,forexample ,tousecomputation geometryalgorithmtodeter minewhetherapointfalls… 相似文献
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The advanced data mining technologies and the large quantities of remotely sensed Imagery provide a data mining opportunity with high potential for useful results. Extracting interesting patterns and rules from data sets composed of images and associated ground data can be of importance in object identification, community planning, resource discovery and other areas. In this paper, a data field is presented to express the observed spatial objects and conduct behavior mining on them. First, most of the important aspects are discussed on behavior mining and its implications for the future of data mining. Furthermore, an ideal framework of the behavior mining system is proposed in the network environment. Second, the model of behavior mining is given on the observed spatial objects, including the objects described by the first feature data field and the main feature data field by means of the potential function. Finally, a case study about object identification in public is given and analyzed. The experimental results show that the new model is feasible in behavior mining. 相似文献
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The advanced data mining technologies and the large quantities of remotely sensed Imagery provide a data mining opportunity
with high potential for useful results. Extracting interesting patterns and rules from data sets composed of images and associated
ground data can be of importance in object identification, community planning, resource discovery and other areas. In this
paper, a data field is presented to express the observed spatial objects and conduct behavior mining on them. First, most
of the important aspects are discussed on behavior mining and its implications for the future of data mining. Furthermore,
an ideal framework of the behavior mining system is proposed in the network environment. Second, the model of behavior mining
is given on the observed spatial objects, including the objects described by the first feature data field and the main feature
data field by means of the potential function. Finally, a case study about object identification in public is given and analyzed.
The experimental results show that the new model is feasible in behavior mining.
Supported by the National 973 Program of China(No.2006CB701305,No.2007CB310804), the National Natural Science Fundation of
China (No.60743001), the Best National Thesis Fundation (No.2005047), the National New Century Excellent Talent Fundation
(No.NCET-06-0618). 相似文献
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Similarity for spatial directions plays an important role in GIS. In this paper, the conventional approaches are analyzed. Based on raster data areal objects, the authors propose two new methods for measuring similarity among spatial directions. One is to measure the similarity among spatial directions based on the features of raster data and the changes of distances between spatial objects, the other is to measure the similarity among spatial directions according to the variation of each raster cell centroid angle. The two methods overcome the complexity of measuring similarity among spatial directions with direction matrix model and solve the limitation of small changes in direction. The two methods are simple and have broader applicability. 相似文献
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Direction is a common spatial concept that is used in our daily life. It is frequently used as a selection condition in spatial queries. As a result, it is important for spatial databases to provide a mechanism for modeling and processing direction queries and reasoning. Depending on the direction relation matrix, an inverted direction relation matrix and the concept of direction pre- dominance are proposed to improve the detection of direction relation between objects. Direction predicates of spatial systems are also extended. These techniques can improve the veracity of direction queries and reasoning. Experiments show excellent efficiency and performance in view of direction queries. 相似文献
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在改进的移动目标空间模型-HCMOST基础上,建立移动目标管理模型,组织和管理监控数据,该优化模型采用三次Hermite插值方法模拟移动目标每个历史单元中的运动轨迹,并把运动函数预先计算出来存放在共享列表中,从而使模型在精度和效率方面有了很大提高。本文基于该模型构建了移动目标管理模型,并分析了构建模型的性能。 相似文献
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FENGYucai YIBaolin 《地球空间信息科学学报》2004,7(4):297-302
Direction is a common spatial concept that is used in our daily life. It is frequently used as a selection condition in spatial queries. As a result, it is important for spatial databases to provide a mechanism for modeling and processing direction queries and reasoning. Depending on the direction relation matrix, an inverted direction relation matrix and the concept of direction pre- dominance are proposed to improve the detection of direction relation between objects. Direction predicates of spatial systems are also extended. These techniques can improve the veracity of direction queries and reasoning. Experiments show excellent efficiency and performance in view of direction queries. 相似文献
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DINGHong GUOQingsheng DUXiaochu 《地球空间信息科学学报》2004,7(3):225-230
Similarity for spatial directions plays an important role in GIS. In this paper, the conventional approaches are analyzed. Based on raster data areal objects, the authors propose two new methods for measuring similarity among spatial directions. One is to measure the similarity among spatial directions based on the features of raster data and the changes of distances between spatial objects, the other is to measure the similarity among spatial directions according to the variation of each raster cell centroid angle. The two methods overcome the complexity of measuring similarity among spatial directions with direction matrix model and solve the limitation of small changes in direction. The two methods are simple and have broader applicability. 相似文献
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空间数据模糊聚类的有效性(英文) 总被引:1,自引:0,他引:1
The validity measurement of fuzzy clustering is a key problem. If clustering is formed, it needs a kind of machine to verify its validity. To make mining more accountable, comprehensible and with a usable spatial pattern, it is necessary to first detect whether the data set has a clustered structure or not before clustering. This paper discusses a detection method for clustered patterns and a fuzzy clustering algorithm, and studies the validity function of the result produced by fuzzy clustering based on two aspects, which reflect the uncertainty of classification during fuzzy partition and spatial location features of spatial data, and proposes a new validity function of fuzzy clustering for spatial data. The experimental result indicates that the new validity function can accurately measure the validity of the results of fuzzy clustering. Especially, for the result of fuzzy clustering of spatial data, it is robust and its classification result is better when compared to other indices. 相似文献
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To overcome the weakness of modelling the relationships between map objects that represent the same geographic entities or phenomena at different times and scales, an agent-based approach is presented to modelling of the spatial evolution of map objects for better understanding of the evolutional process of different maps. Map agents are used to establish and manage the many-to-many corresponding relationships between map objects, and they render map objects active rather than traditionally passive. The evolutions of map objects are modelled by map agents using association and generation relationships to model the connectivity between map objects. This effort reduces the workload of multi-scale map updating by avoiding update of the entire map; instead, it simply allows map agents to detect, perceive and choose suitable behaviours on which to operate and update a spatially evolving object. Experiments of specific examples are presented to demonstrate the feasibility and the effectiveness of our approach. 相似文献
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Kimfung Liu Wenzhong Shi 《International Journal of Applied Earth Observation and Geoinformation》2009
This paper presents a study on the modeling of fuzzy topological relations between uncertain objects in Geographic Information Systems (GIS). Based on the recently developed concept of computational fuzzy topological space, topological relations between simple fuzzy spatial objects are modeled. The fuzzy spatial objects here cover simple fuzzy region, simple fuzzy line segment and fuzzy point. To compute the topological relations between the simple spatial objects, intersection concepts and integration methods are applied and a computational 9-intersection model are proposed and developed. There are different types of intersection, and we have proposed different integration methods for computation in different cases. For example, surface integration method is applied to the case of the fuzzy region-to-fuzzy region relation, while the line integration method is used in the case of fuzzy line segment-to-fuzzy line segment relation. Moreover, this study has discovered that there are (a) sixteen topological relations between simple fuzzy region to line segment; (b) forty-six topological relations between simple fuzzy line segments; (c) three topological relations between simple fuzzy region to fuzzy point; and (d) three topological relations between simple fuzzy line segment to fuzzy point. 相似文献
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以往的高光谱或多光谱图像分类与识别,往往只关注像元光谱维上的特性,其一切特征统计也只在光谱及波段维上展开。但是自然界的复杂性、混合像元问题的存在,仅靠像元的光谱特性是不够的,常会出现"麻点"现象。针对这一问题,本文提出一种结合地物空间特性的高光谱图像分类方法,其分类过程可以分为两个阶段,第一阶段是基于像元光谱特性的图像分类,获得影像分类图;第二阶段是针对第一阶段的分类结果,结合地物空间特性进行空间后分类处理。试验研究结果表明,该方法能够保持地块的连续性和均一性,同时克服了"麻点"现象,大大提高分类的精度。 相似文献