检索结果-内蒙古大学图书馆

Efficient Space Management Techniques for Large-Scale Interconnect Capacitance Extraction With Floating Random Walks

引用

IEEE TRANSACTIONS ON COMPUTER-AIDED DESIGN OF INTEGRATED CIRCUITS AND SYSTEMS 2013年第10期32卷 1633-1637页

作者： Zhang, Chao Yu, Wenjian Tsinghua Univ Dept Comp Sci & Technol Beijing 100084 Peoples R China

In the capacitance extraction with the floating random walk (FRW) algorithm, the space management approach is required to facilitate finding the nearest conductor. The Octree and grid-based spatial structures have been used to decompose the whole domain into cells and to store information of local conductors. In this letter, the techniques with the distance limit of cell and only searching in cell's neighbor region are proposed to accelerate the construction of the spatial structures. A fast inquiry technique is proposed to fasten the nearest conductor query. We also propose a grid-Octree hybrid structure, which has advantages over existing structures. Experiments on large very large scale integration structures with up to 484 441 conductors have validated the efficiency of the proposed techniques. The improved FRW algorithm is faster than RWCap for thousands times while extracting a single net, and several to tens times while extracting 100 nets.

关键词： Capacitance extraction floating random walk (FRW) space management spatial data structure very large scale integration (VLSI) circuit

来源：评论

学校读者我要写书评

暂无评论

A Knowledge Driven Model: Extract Knowledge from High Dimensional Medical databases

A Knowledge Driven Model: Extract Knowledge from High Dimens...

引用

IEEE International Conference on Machine Intelligence Research and Advancement (ICMIRA)

作者： Chauhan, Ritu Kaur, Harleen Hamdard Univ New Delhi India

ISBN: (纸本)9780769550138

The extensive amount of spatial databases accumulated from various computed technology requires automated data mining tools to discover hidden and novel information from large and complex databases. In other words, the major concern is high dimensionality and complexity of spatial data which has created serious concerns among the researchers to retrieve effective and efficient clusters from large and complex spatial features. In this paper we have proposed a spatial clustering algorithm (SPAS) and Knowledge driven framework to discover clusters of variant shapes and size with domain specific knowledge. The application of our proposed algorithm is tested on real world spatial medical databases collected from SEER datasets which has record of Lung cancer patients from the year 1975 - 2008. The case includes information on patient's gender, ZIP code of a patient's residence, year of diagnosis, primary site, stage at diagnosis, and age group. Each record represents a diagnosed cancer case assigned to the patient's residence at time of diagnosis. The objective of study was to discover effective and efficient spatial clusters with domain specific knowledge for futuristic decision making.

关键词： spatial data Mining spatial databases spatial data structure spatial Clustering Knowledge Discovery

来源：评论

学校读者我要写书评

暂无评论

spatial data Topology in GIS database

Spatial Data Topology in GIS Database

引用

International Conference on Materials Science and Information Technology (MSIT 2011)

作者： Sun, Yunpeng Liaoning Normal Univ 2 Coll City & Environm Tangshan Teachers Coll Dalian Peoples R China

ISBN: (纸本)9783037853191

Topology and its various benefits and functionality are fairly well understood within the context of 2D Geographical Information Systems. We summarize the principle of common 2D topology and the implementation of GIS databases. Existing topological frameworks and data models as a staring point to guide the review process, three key areas were studied for the purposes of requirements identification, namely existing 2D topological systems. However requirements in 3D have yet to be defined, with factors such as lack of familiarity with the potential of such functionality of 3D systems impeding this process. In this paper, we identify and review the requirements for topology in three-dimensional (3D) applications. Requirements for topological functionality in 3D were then grouped and categorized.

关键词： Topology GIS database spatial data structure

来源：评论

学校读者我要写书评

暂无评论

An extended technique for R-tree to manage multiple type objects

引用

JOURNAL OF COMPUTATIONAL METHODS IN SCIENCES AND ENGINEERING 2012年第1_suppl期12卷 S53-S61页

作者： Dekihara, Hiroyuki Nakamura, Yasuaki Hiroshima Int Univ Dept Informat Technol 5-1-1 Hirokoshingai Kure Hiroshima 7370112 Japan Technobits Co Ltd Tokyo Japan

In this paper, we propose a new technique for managing multiple type objects in systems such as GIS and CAD. The novel concept of our mechanism is to separate the objects in a data structure according to the type identifier of the objects. The type identifier is a binary number that signifies a bit pattern corresponding to the type of the object. By means of the type identifier, a data structure can manage not only the space information of objects but also the types of objects. Therefore, in our mechanism, access performance does not depend on the number of all objects, as in most of the past methods, but rather on the number of objects in the type identifier. Also, access and memory performance do not deteriorate even if the types of objects are not independent. The performance of our system is evaluated by simulation tests.

关键词： spatial data spatial data structure R-tree multiple type objects

来源：评论

学校读者我要写书评

暂无评论

Applying the Dynamic Region Connection Calculus to Exploit Geographic Knowledge in Maritime Surveillance

Applying the Dynamic Region Connection Calculus to Exploit G...

引用

International Conference on Information Fusion

作者： M.A. Serrano J. Gómez-Romero M.A. Patricio J. García J.M. Molina GIAA Research Group Universidad Carlos III de Madrid (UC3M) Colmenarejo Spain

ISBN: (纸本)9780982443859

Concerns about the protection of the global transport network have risen the need of new security and surveillance systems. Ontology-based and fusion systems represent an attractive alternative for practical applications focused on fast and accurate responses. This paper presents an architecture based on a geometric model to efficiently predict and calculate the topological relationships between spatial objects. This model aims to reduce the number of calculations by relying on a spatial data structure. The goal is the detection of threatening behaviors next to points of interest without a noticeable loss of efficiency. The architecture has been embedded in an ontology-based prototype compliant with the Joint Directors of Laboratories (JDL) model for Information Fusion. The prototype capabilities are illustrated by applying international protection rules in maritime scenarios.

关键词： High-Level Fusion Region Connection Calculus Ontology-based Application spatial data structure

来源：评论

学校读者我要写书评

暂无评论

Nearest neighbor search algorithm for GBD tree spatial data structure

Nearest neighbor search algorithm for GBD tree spatial data ...

引用

5th Asian Symposium on Geographic Information System from Computer Science & Engineering View

作者： Yutaka Ohsawa Takanobu Kurihara Ayaka Ohki Saitama University Saitama 338-8570Japan

＜正＞This paper describes the nearest neighbor（NN）search algorithm on the GBD（generalized BD）*** GBD tree is a spatial data structure suitable for two-or three-dimensional data and has good performance characteris- tics with respect to the dynamic data *** GIS and CAD systems,the R-tree and its successors have been *** addition,the NN search algorithm is also proposed in an attempt to obtain good performance from the *** the other hand,the GBD tree is superior to the R-tree with respect to exact match retrieval,because the GBD tree has auxiliary data that uniquely determines the position of the object in the *** proposed NN search algorithm depends on the property of the GBD tree described *** NN search algorithm on the GBD tree was studied and the performance thereof was evaluated through experiments.

关键词： nearest neighbor search algorithm GBD tree spatial data structure

来源：评论

学校读者我要写书评

暂无评论

Linear Quadtree Construction in Real Time

引用

JOURNAL OF INFORMATION SCIENCE AND ENGINEERING 2010年第5期26卷 1917-1930页

作者： Huang, Chi-Yen Chen, Yu-Wei Natl Taipei Coll Business Dept Informat Management Taipei 100 Taiwan Natl Taipei Univ Technol Grad Inst Informat & Logist Management Taipei 106 Taiwan

The paper presents a novel method for encoding the linear quadtree of a given image. In this method, the pixels of the image are scanned in row major order. In each encountered pixel, the result codes in the linear quadtree are updated simultaneously in real time. The linear quadtree is thus obtained after all pixels are processed. This method is quite different from those in previous studies, which need huge memory space to store the input pixels for further processing, or need post processing to rearrange the sequence of the final codes to put them back in increasing order. Moreover, since this method adopts simpler and more efficient operations than previous methods, it is found to be faster in experiments.

关键词： linear quadtree linear bintree spatial data structure image encoding locational code

来源：评论

学校读者我要写书评

暂无评论

Design and Realization of Environment Information Sharing Platform

Design and Realization of Environment Information Sharing Pl...

引用

International Forum on Information Technology and Applications (IFITA 2009)

作者： Hu Qiang Liu Nian Wang Diangang Liu Sunjun Xu Chun Chengdu Univ Teaching Affairs Dept Chengdu 610106 Peoples R China Sichuan Univ Coll Comp Sci Chengdu 610065 Peoples R China Sichuan Univ Sch Elect Engn & Informat Chengdu 610065 Peoples R China Chengdu Univ Inforamt Technol Coll Software Engn Chengdu 610225 Peoples R China Sichuan Elect Vocat & Techn Coll Chengdu 610072 Peoples R China

ISBN: (纸本)9780769536002

Environment problems are becoming the hot spots of society, and how to realize the sharing of data information and avoid the phenomenon of information isolated island is in urgent need for current environment protection department This article aims to build a unified environment information sharing platform to realize information resource exchange between different systems. Departments and levels as well as horizontal and longitudinal exchange in order to simplify the difficulties of environment data management and increase the level of environment data management by integrating various applications and data resources.

关键词： data share spatial data structure environment protection

来源：评论

学校读者我要写书评

暂无评论

The comparison map profile method:: A strategy for multiscale comparison of quantitative and qualitative images

引用

IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING 2008年第9期46卷 2708-2719页

作者： Gaucherel, Cedric Alleaume, Samuel Hely, Christelle Aix Marseille Univ CNRS CDF IRDCEREGE F-13545 Aix En Provence France

The comparison map profile (CMP) method compares two spatially explicit data sets (original images) at each point and through several spatial scales simultaneously. The CMP combines the moving window concept with similarity indices for quantitative or qualitative data to visualize and quantify outputs: Changes in mean similarity value and its variability through scales are reported on a profile, similarities between regions are estimated on monoscale maps, and their persistence through scales assessed on a mean multiscale map. The CMP method is first illustrated using two images with slight difference in the checkered pattern. Second, two sets of comparisons related to African vegetation are conducted using the CMP method. The first set deals with quantitative data of leaf area index (LAI): Remote-sensed LAI images extracted from the AVHRR-NVDI product are compared to simulated LAI output from a dynamic global vegetation model DGVM) using the distance and the cross-correlational coefficient for quantitative comparison of values and structure patterns, respectively,. The second set of images deals with qualitative data: the remote-sensed product of land cover type by IGBP-NIODIS is compared to the DGVM classified LAI output into land cover types using the Kappa statistics as similarity index. Results show that taking spatial patterns into account using the CMP method decreases the mean correlation by 50%, and increases the distance by 50% as compared to the global pixel-to-pixel indices. Similarly, comparison of land cover maps costs only 35% of the global Kappa value. Equatorial gradients of vegetation from forests to grassland are the most persistent similar regions between both types of data sets. Potential limits and strengths of the CMP method are discussed.

关键词： environmental factors image texture analysis spatial data structure vegetation mapping

来源：评论

学校读者我要写书评

暂无评论

An efficient update algorithm for spatial data structures managing moving objects

An efficient update algorithm for spatial data structures ma...

引用

4th International Conference on Cybernetics and Information Technologies, Systems and Applications/5th Int Conf on Computing, Communications and Control Technologies

作者： Dekihara, Hiroyuki Nakamura, Yasuaki Hiroshima Int Univ Dept Informat Technol 5-1-1 Hiro Koshingai Kure Hiroshima 7370012 Japan TTT Co Ltd Toshima Ku Tokyo 1700005 Japan Japan Data & Commun Res Inst Minato Ku Tokyo Japan

ISBN: (纸本)9781934272077

In the fields of GIS (Geographic Information System), ITS (Intelligent Transportation System), monitoring systems, and so forth, the spatial data structures for the management of moving objects are very important. Moving objects may change their attributes: location, direction, condition, etc. Therefore, the spatial data structure must manage moving objects efficiently to perform queries that search or trace the spatial data any, time. However, when the data structure is updated at every unit time, the update cost will highly increase. In this paper, an efficient update algorithm for spatial data structures managing moving objects, called the SBUA (the Simplified Batch Updating Algorithm) is proposed. The novel concepts of the SBUA are a botch insertion using a buffer array, and a simplified restructuring according to the location changes of objects. The SBUA saves the update cost of the tree by using the buffer array in which reported new locations of the moving objects are stored. Moreover, the search performances of the SBUA are kept althought the restructuring of the tree is not performed completely.

关键词： spatial data structure moving objects MD-tree

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：