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Optimal Tracking Control for a Class of Unknown Discrete-time Systems with Actuator Saturation via Data-based ADP Algorithm 被引量:4
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作者 SONG Rui-Zhuo XIAO Wen-Dong SUN Chang-Yin 《自动化学报》 EI CSCD 北大核心 2013年第9期1413-1420,共8页
为有致动器浸透和未知动力学的分离时间的系统的一个班的一个新奇最佳的追踪控制方法在这份报纸被建议。计划基于反复的适应动态编程(自动数据处理) 算法。以便实现控制计划,一个 data-based 标识符首先为未知系统动力学被构造。由介绍... 为有致动器浸透和未知动力学的分离时间的系统的一个班的一个新奇最佳的追踪控制方法在这份报纸被建议。计划基于反复的适应动态编程(自动数据处理) 算法。以便实现控制计划,一个 data-based 标识符首先为未知系统动力学被构造。由介绍 M 网络,稳定的控制的明确的公式被完成。以便消除致动器浸透的效果, nonquadratic 表演功能被介绍,然后一个反复的自动数据处理算法被建立与集中分析完成最佳的追踪控制解决方案。为实现最佳的控制方法,神经网络被用来建立 data-based 标识符,计算性能索引功能,近似最佳的控制政策并且分别地解决稳定的控制。模拟例子被提供验证介绍最佳的追踪的控制计划的有效性。 展开更多
关键词 最优跟踪控制 离散时间系统 饱和执行器 DP算法 控制方案 神经网络 性能指标 系统动力学
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The IRIS Development Platform and Proposed Object-Oriented Data Base 被引量:1
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作者 Mihai-Octavian Dima 《Journal of Software Engineering and Applications》 2015年第4期167-174,共8页
Various code development platforms, such as the ATHENA Framework [1] of the ATLAS [2] experiment encounter lengthy compilation/linking times. To augment this situation, the IRIS Development Platform was built as a sof... Various code development platforms, such as the ATHENA Framework [1] of the ATLAS [2] experiment encounter lengthy compilation/linking times. To augment this situation, the IRIS Development Platform was built as a software development framework acting as compiler, cross-project linker and data fetcher, which allow hot-swaps in order to compare various versions of software under test. The flexibility fostered by IRIS allowed modular exchange of software libraries among developers, making it a powerful development tool. The IRIS platform used input data ROOT-ntuples [3];however a new data model is sought, in line with the facilities offered by IRIS. The schematic of a possible new data structuring—as a user implemented object oriented data base, is presented. 展开更多
关键词 SOFTWARE Development PLATFORM User-Defined OBJECT ORIENTED data-base
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A Path-Based Approach for Data Aggregation in Grid-Based Wireless Sensor Networks 被引量:1
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作者 Neng-Chung Wang Yung-Kuei Chiang Chih-Hung Hsieh 《Journal of Electronic Science and Technology》 CAS 2014年第3期313-317,共5页
Sensor nodes in a wireless sensor network (WSN) are typically powered by batteries, thus the energy is constrained. It is our design goal to efficiently utilize the energy of each sensor node to extend its lifetime,... Sensor nodes in a wireless sensor network (WSN) are typically powered by batteries, thus the energy is constrained. It is our design goal to efficiently utilize the energy of each sensor node to extend its lifetime, so as to prolong the lifetime of the whole WSN. In this paper, we propose a path-based data aggregation scheme (PBDAS) for grid-based wireless sensor networks. In order to extend the lifetime of a WSN, we construct a grid infrastructure by partitioning the whole sensor field into a grid of cells. Each cell has a head responsible for aggregating its own data with the data sensed by the others in the same cell and then transmitting out. In order to efficiently and rapidly transmit the data to the base station (BS), we link each cell head to form a chain. Each cell head on the chain takes turn becoming the chain leader responsible for transmitting data to the BS. Aggregated data moves from head to head along the chain, and finally the chain leader transmits to the BS. In PBDAS, only the cell heads need to transmit data toward the BS. Therefore, the data transmissions to the BS substantially decrease. Besides, the cell heads and chain leader are designated in turn according to the energy level so that the energy depletion of nodes is evenly distributed. Simulation results show that the proposed PBDAS extends the lifetime of sensor nodes, so as to make the lifetime of the whole network longer. 展开更多
关键词 base station cell head data aggregation grid-based wireless sensor networks
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Variable binaries and variables in binaries in the Binary star DataBase
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作者 Dana Kovaleva Oleg Malkov Pavel Kaygorodov 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2019年第3期7-12,共6页
The Binary star DataBase(BDB, http://bdb.inasan.ru) combines data from catalogs of binary and multiple stars of all observational types. There is a number of ways for variable stars to form or to be a part of binary o... The Binary star DataBase(BDB, http://bdb.inasan.ru) combines data from catalogs of binary and multiple stars of all observational types. There is a number of ways for variable stars to form or to be a part of binary or multiple systems. We describe how such stars are represented in the database. 展开更多
关键词 astronomical data bases-stars BINARIES general-stars VARIABLES GENERAL
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Data Mining and Neural Network Techniques in Case Based System 被引量:2
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作者 Ni Zhi wei 1,2 , Cai Qing sheng 1, Li Long shu 2 1.Department of Computer Science, University of Science and Technology of China,Hefei 230027,China 2.The Key Laboratory of Intelligent Computing and Signal Processing ,Ministry of Education 《Wuhan University Journal of Natural Sciences》 CAS 2001年第Z1期601-605,共5页
This paper first puts forward a case based system framework based on data mining techniques. Then the paper examines the possibility of using neural networks as a method of retrieval in such a case based system. In ... This paper first puts forward a case based system framework based on data mining techniques. Then the paper examines the possibility of using neural networks as a method of retrieval in such a case based system. In this system we propose data mining algorithms to discover case knowledge and other algorithms. 展开更多
关键词 data mining neural network case based reasoning retrieval algorithm
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Percentile-based Neighborhood Precipitation Verification and Its Application to a Landfalling Tropical Storm Case with Radar Data Assimilation 被引量:3
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作者 ZHU Kefeng YANG Yi Ming XUE 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2015年第11期1449-1459,共11页
The traditional threat score based on fixed thresholds for precipitation verification is sensitive to intensity forecast bias. In this study, the neighborhood precipitation threat score is modified by defining the thr... The traditional threat score based on fixed thresholds for precipitation verification is sensitive to intensity forecast bias. In this study, the neighborhood precipitation threat score is modified by defining the thresholds in terms of the percentiles of overall precipitation instead of fixed threshold values. The impact of intensity forecast bias on the calculated threat score is reduced. The method is tested with the forecasts of a tropical storm that re-intensified after making landfall and caused heavy flooding. The forecasts are produced with and without radar data assimilation. The forecast with assimilation of both radial velocity and reflectivity produce precipitation patterns that better match observations but have large positive intensity bias. When using fixed thresholds, the neighborhood threat scores fail to yield high scores for forecasts that have good pattern match with observations, due to large intensity bias. In contrast, the percentile-based neighborhood method yields the highest score for the forecast with the best pattern match and the smallest position error. The percentile-based method also yields scores that are more consistent with object-based verifications, which are less sensitive to intensity bias, demonstrating the potential value of percentile-based verification. 展开更多
关键词 neighborhood precipitation threat score percentile-based verification radar data assimilation
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“Deep-time Digital Basin” Based on Big Data and Artificial Intelligence 被引量:2
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作者 FENG Zhiqing LIAN Peiqing 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2019年第S01期14-16,共3页
1 Introduction Information technology has been playing an ever-increasing role in geoscience.Sphisicated database platforms are essential for geological data storage,analysis and exchange of Big Data(Feblowitz,2013;Zh... 1 Introduction Information technology has been playing an ever-increasing role in geoscience.Sphisicated database platforms are essential for geological data storage,analysis and exchange of Big Data(Feblowitz,2013;Zhang et al.,2016;Teng et al.,2016;Tian and Li,2018).The United States has built an information-sharing platform for state-owned scientific data as a national strategy. 展开更多
关键词 deep-time DIGITAL earth(DDE) deep-time DIGITAL basin(DDB) BIG data artificial intelligent knowledge base
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Semantic Analysis of Natural Language Queries for an Object Oriented Database
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作者 Bentamar Hemerelain Hafida Belbachir 《Journal of Software Engineering and Applications》 2010年第11期1047-1053,共7页
This paper presents the semantic analysis of queries written in natural language (French) and dedicated to the object oriented data bases. The studied queries include one or two nominal groups (NG) articulating around... This paper presents the semantic analysis of queries written in natural language (French) and dedicated to the object oriented data bases. The studied queries include one or two nominal groups (NG) articulating around a verb. A NG consists of one or several keywords (application dependent noun or value). Simple semantic filters are defined for identifying these keywords which can be of semantic value: class, simple attribute, composed attribute, key value or not key value. Coherence rules and coherence constraints are introduced, to check the validity of the co-occurrence of two consecutive nouns in complex NG. If a query is constituted of a single NG, no further analysis is required. Otherwise, if a query covers two valid NG, it is a subject of studying the semantic coherence of the verb and both NG which are attached to it. 展开更多
关键词 QUERY NOMINAL Group Natural LANGUAGE Object Oriented data base SEMANTIC Validation
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Free-matrix-based time-dependent discontinuous Lyapunov functional for synchronization of delayed neural networks with sampled-data control 被引量:1
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作者 王炜 曾红兵 Kok-Lay Teo 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第11期127-134,共8页
This paper is concerned with the synchronization of delayed neural networks via sampled-data control. A new technique, namely, the free-matrix-based time-dependent discontinuous Lyapunov functional approach, is adopte... This paper is concerned with the synchronization of delayed neural networks via sampled-data control. A new technique, namely, the free-matrix-based time-dependent discontinuous Lyapunov functional approach, is adopted in constructing the Lyapunov functional, which takes advantage of the sampling characteristic of sawtooth input delay. Based on this discontinuous Lyapunov functional, some less conservative synchronization criteria are established to ensure that the slave system is synchronous with the master system. The desired sampled-data controller can be obtained through the use of the linear matrix inequality(LMI) technique. Finally, two numerical examples are provided to demonstrate the effectiveness and the improvements of the proposed methods. 展开更多
关键词 neural networks synchronization sampled-data control free-matrix-based inequality
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Web-Based Data Management and Sharing System for Electron Proke Micro-analysis
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作者 HE Yutong TIAN Di +3 位作者 GAO Ranran FAN Runlong YAO Li CHEN Pengfei 《Journal of Donghua University(English Edition)》 EI CAS 2018年第4期315-320,共6页
This paper proposes a useful web-based system for the management and sharing of electron probe micro-analysis( EPMA)data in geology. A new web-based architecture that integrates the management and sharing functions is... This paper proposes a useful web-based system for the management and sharing of electron probe micro-analysis( EPMA)data in geology. A new web-based architecture that integrates the management and sharing functions is developed and implemented.Earth scientists can utilize this system to not only manage their data,but also easily communicate and share it with other researchers.Data query methods provide the core functionality of the proposed management and sharing modules. The modules in this system have been developed using cloud GIS technologies,which help achieve real-time spatial area retrieval on a map. The system has been tested by approximately 263 users at Jilin University and Beijing SHRIMP Center. A survey was conducted among these users to estimate the usability of the primary functions of the system,and the assessment result is summarized and presented. 展开更多
关键词 ELECTRON probe micro-analysis ( EPMA ) data management data sharing WEB-baseD architecture data query GIS
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Data preprocessing and preliminary results of the Moon-based Ultraviolet Telescope on the CE-3 lander 被引量:4
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作者 Wei-Bin Wen Fang Wang +8 位作者 Chun-Lai Li Jing Wang Li Cao Jian-Jun Liu Xu Tan Yuan Xiao Qiang Fu Yan Su Wei Zuo 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2014年第12期1674-1681,共8页
The Moon-based Ultraviolet Telescope (MUVT) is one of the payloads on the Chang'e-3 (CE-3) lunar lander. Because of the advantages of having no at- mospheric disturbances and the slow rotation of the Moon, we can... The Moon-based Ultraviolet Telescope (MUVT) is one of the payloads on the Chang'e-3 (CE-3) lunar lander. Because of the advantages of having no at- mospheric disturbances and the slow rotation of the Moon, we can make long-term continuous observations of a series of important celestial objects in the near ultra- violet band (245-340 nm), and perform a sky survey of selected areas, which can- not be completed on Earth. We can find characteristic changes in celestial brightness with time by analyzing image data from the MUVT, and deduce the radiation mech- anism and physical properties of these celestial objects after comparing with a phys- ical model. In order to explain the scientific purposes of MUVT, this article analyzes the preprocessing of MUVT image data and makes a preliminary evaluation of data quality. The results demonstrate that the methods used for data collection and prepro- cessing are effective, and the Level 2A and 2B image data satisfy the requirements of follow-up scientific researches. 展开更多
关键词 Chang'e-3 mission -- the Moon-based Ultraviolet Telescope -- data preprocessing -- near ultraviolet band
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Model-based predictive controller design for a class of nonlinear networked systems with communication delays and data loss
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作者 安宝冉 刘国平 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第8期211-216,共6页
This paper discusses the model-based predictive controller design of networked nonlinear systems with communica- tion delay and data loss. Based on the analysis of the closed-loop networked predictive control systems,... This paper discusses the model-based predictive controller design of networked nonlinear systems with communica- tion delay and data loss. Based on the analysis of the closed-loop networked predictive control systems, the model-based networked predictive control strategy can compensate for communication delay and data loss in an active way. The designed model-based predictive controller can also guarantee the stability of the closed-loop networked system. The simulation re- suits demonstrate the feasibility and efficacy of the proposed model-based predictive controller design scheme. 展开更多
关键词 communication delays data loss model-based networked predictive control
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Optical-Elevation Data Co-Registration and Classification-Based Height Normalization for Building Detection in Stereo VHR Images 被引量:1
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作者 Alaeldin Suliman Yun Zhang 《Advances in Remote Sensing》 2017年第2期103-119,共17页
Building detection in very high resolution (VHR) images is crucial for mapping and analysing urban environments. Since buildings are elevated objects, elevation data need to be integrated with images for reliable dete... Building detection in very high resolution (VHR) images is crucial for mapping and analysing urban environments. Since buildings are elevated objects, elevation data need to be integrated with images for reliable detection. This process requires two critical steps: optical-elevation data co-registration and aboveground elevation calculation. These two steps are still challenging to some extent. Therefore, this paper introduces optical-elevation data co-registration and normalization techniques for generating a dataset that facilitates elevation-based building detection. For achieving accurate co-registration, a dense set of stereo-based elevations is generated and co-registered to their relevant image based on their corresponding image locations. To normalize these co-registered elevations, the bare-earth elevations are detected based on classification information of some terrain-level features after achieving the image co-registration. The developed method was executed and validated. After implementation, 80% overall-quality of detection result was achieved with 94% correct detection. Together, the developed techniques successfully facilitate the incorporation of stereo-based elevations for detecting buildings in VHR remote sensing images. 展开更多
关键词 Building Detection Very High Resolution Images Optical-Elevation data CO-REGISTRATION Classification-based Height Normalization
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Tracking data management using topology of moving object database system for moving object constrained trajectory in LBS application 被引量:1
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作者 LEE Hyun jin SIM Tai jung +2 位作者 JANG Yong ll PARK Soon young BAE Hae young 《重庆邮电学院学报(自然科学版)》 2004年第5期50-57,共8页
Advances in wireless technologies and positioning technologies and spread of wireless devices, an interest in LBS(Location Based Service) is arising. To provide location based service, tracking data should have been s... Advances in wireless technologies and positioning technologies and spread of wireless devices, an interest in LBS(Location Based Service) is arising. To provide location based service, tracking data should have been stored in moving object database management system (called MODBMS) with proper policies and managed efficiently. So the methods which acquire the location information at regular time intervals then, store and manage have been studied. In this paper, we suggest tracking data management techniques using topology that is corresponding to the moving path of moving object. In our techniques, we update the MODBMS when moving object arrived at a street intersection or a curved road which is represented as the node in topology and predict the location at past and future with attribute of topology and linear function. In this technique, location data that are corresponding to the node in topology are stored, thus reduce the number of update and amount of data. Also in case predicting the location, because topology are used as well as existing location information, accuracy for prediction is increased than applying linear function or spline function. 展开更多
关键词 面向对象数据库系统 跟踪数据管理 拓扑 强迫轨道 LBS 定位服务 MODBMS
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Analysis of Complex Correlated Interval-Censored HIV Data from Population Based Survey
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作者 Khangelani Zuma Goitseone Mafoko 《Open Journal of Statistics》 2015年第2期120-126,共7页
In studies of HIV, interval-censored data occur naturally. HIV infection time is not usually known exactly, only that it occurred before the survey, within some time interval or has not occurred at the time of the sur... In studies of HIV, interval-censored data occur naturally. HIV infection time is not usually known exactly, only that it occurred before the survey, within some time interval or has not occurred at the time of the survey. Infections are often clustered within geographical areas such as enumerator areas (EAs) and thus inducing unobserved frailty. In this paper we consider an approach for estimating parameters when infection time is unknown and assumed correlated within an EA where dependency is modeled as frailties assuming a normal distribution for frailties and a Weibull distribution for baseline hazards. The data was from a household based population survey that used a multi-stage stratified sample design to randomly select 23,275 interviewed individuals from 10,584 households of whom 15,851 interviewed individuals were further tested for HIV (crude prevalence = 9.1%). A further test conducted among those that tested HIV positive found 181 (12.5%) recently infected. Results show high degree of heterogeneity in HIV distribution between EAs translating to a modest correlation of 0.198. Intervention strategies should target geographical areas that contribute disproportionately to the epidemic of HIV. Further research needs to identify such hot spot areas and understand what factors make these areas prone to HIV. 展开更多
关键词 Analysis of COMPLEX CORRELATED Interval-Censored HIV data from Population based SURVEY
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LeaDen-Stream: A Leader Density-Based Clustering Algorithm over Evolving Data Stream
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作者 Amineh Amini Teh Ying Wah 《Journal of Computer and Communications》 2013年第5期26-31,共6页
Clustering evolving data streams is important to be performed in a limited time with a reasonable quality. The existing micro clustering based methods do not consider the distribution of data points inside the micro c... Clustering evolving data streams is important to be performed in a limited time with a reasonable quality. The existing micro clustering based methods do not consider the distribution of data points inside the micro cluster. We propose LeaDen-Stream (Leader Density-based clustering algorithm over evolving data Stream), a density-based clustering algorithm using leader clustering. The algorithm is based on a two-phase clustering. The online phase selects the proper mini-micro or micro-cluster leaders based on the distribution of data points in the micro clusters. Then, the leader centers are sent to the offline phase to form final clusters. In LeaDen-Stream, by carefully choosing between two kinds of micro leaders, we decrease time complexity of the clustering while maintaining the cluster quality. A pruning strategy is also used to filter out real data from noise by introducing dense and sparse mini-micro and micro-cluster leaders. Our performance study over a number of real and synthetic data sets demonstrates the effectiveness and efficiency of our method. 展开更多
关键词 EVOLVING data STREAMS Density-based Clustering Micro CLUSTER Mini-Micro CLUSTER
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Creating Bengali Freebase Using Wikidata
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作者 Rukaiya Habib Mahmuda Ferdous Md Musfique Anwar 《Journal of Computer and Communications》 2023年第5期151-160,共10页
Freebase is a large collaborative knowledge base and database of general, structured information for public use. Its structured data had been harvested from many sources, including individual, user-submitted wiki cont... Freebase is a large collaborative knowledge base and database of general, structured information for public use. Its structured data had been harvested from many sources, including individual, user-submitted wiki contributions. Its aim is to create a global resource so that people (and machines) can access common information more effectively which is mostly available in English. In this research work, we have tried to build the technique of creating the Freebase for Bengali language. Today the number of Bengali articles on the internet is growing day by day. So it has become a necessary to have a structured data store in Bengali. It consists of different types of concepts (topics) and relationships between those topics. These include different types of areas like popular culture (e.g. films, music, books, sports, television), location information (restaurants, geolocations, businesses), scholarly information (linguistics, biology, astronomy), birth place of (poets, politicians, actor, actress) and general knowledge (Wikipedia). It will be much more helpful for relation extraction or any kind of Natural Language Processing (NLP) works on Bengali language. In this work, we identified the technique of creating the Bengali Freebase and made a collection of Bengali data. We applied SPARQL query language to extract information from natural language (Bengali) documents such as Wikidata which is typically in RDF (Resource Description Format) triple format. 展开更多
关键词 KNOWLEDGE-base Structured data NLP RDF
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Fast Web - Based Data Transmission 被引量:2
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作者 Wei Zukuan Department of Computer Science & Engineering, Inha University, Inchon 402 751, Korea Kim Jaehong Department of Computer Science, Youngdong University, Youngdong, Korea Bae Haeyoung Department of Computer Science & Engineering, Inha Uni 《Journal of China University of Geosciences》 SCIE CSCD 2001年第2期165-176,共12页
Since web based GIS processes large size spatial geographic information on internet, we should try to improve the efficiency of spatial data query processing and transmission. This paper presents two efficient metho... Since web based GIS processes large size spatial geographic information on internet, we should try to improve the efficiency of spatial data query processing and transmission. This paper presents two efficient methods for this purpose: division transmission and progressive transmission methods. In division transmission method, a map can be divided into several parts, called “tiles”, and only tiles can be transmitted at the request of a client. In progressive transmission method, a map can be split into several phase views based on the significance of vertices, and a server produces a target object and then transmits it progressively when this spatial object is requested from a client. In order to achieve these methods, the algorithms, “tile division”, “priority order estimation” and the strategies for data transmission are proposed in this paper, respectively. Compared with such traditional methods as “map total transmission” and “layer transmission”, the web based GIS data transmission, proposed in this paper, is advantageous in the increase of the data transmission efficiency by a great margin. 展开更多
关键词 spatial data transmission spatial query processing web based GIS geographic information system spatial database.
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Prediction-Based Lossless Data Hiding by ACB Algorithm
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作者 Ching-Yu Yang Chih-Hung Lin Wu-Chih Hu 《通讯和计算机(中英文版)》 2012年第2期142-147,共6页
关键词 无损数据隐藏 算法 预测 自适应偏置 存储空间 图像质量 有效载荷 去除率
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Spatial aggregations for spatial based decision making in spatial data warehouses
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作者 ByeongSeob You DongWook Lee +2 位作者 SangHun Eo SookKyung Cho HaeYoung Bae 《重庆邮电大学学报(自然科学版)》 2007年第3期318-322,共5页
For spatial based decision making such as choice of best place to construct a new department store, spatial data warehousing system is required more and more previous spatial data warehousing systems; however, provide... For spatial based decision making such as choice of best place to construct a new department store, spatial data warehousing system is required more and more previous spatial data warehousing systems; however, provided decision making of non-spatial data on a map and so those cannot support enough spatial based decision making. The spatial aggregations are proposed for spatial based decision making in spatial data warehouses. The meaning of aggregation operators for applying spatial data was modified and new spatial aggregations were defined. These aggregations can support hierarchical concept of spatial measure. Using these aggregations, the spatial analysis classified by non-spatial data is provided. In case study, how to use these aggregations and how to support spatial based decision making are shown. 展开更多
关键词 空间数据 空间集合体 空间决策 数据库
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