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GRAPHICS DATA STRUCTURES IN MICROCOMPUTER AIDED DESIGN FOR OPEN PIT PLANNING
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作者 吴力心 《Journal of China University of Mining and Technology》 1991年第1期88-96,共9页
This paper discribes the importance and necessity of the study on the data structures for displaying the mining field using the interactive technology in open pit design and planning,based upon the grid block model. T... This paper discribes the importance and necessity of the study on the data structures for displaying the mining field using the interactive technology in open pit design and planning,based upon the grid block model. The commonly used data structures--rectangular array structure and quadtree structure ,are analyzed. Two compressed data structures--compressed circular link array structure and compressed doubly-linked circular array structure,are proposed,which are much more suitable for displaying the regularly gridded block model. When the two compressed data structures are adopted,the storage space can be tremendously saved and the algorithms are simple,while the requirements of the accuracy and the manipulating speed will be both satisfied for the interactive open pit short range plan formulation. 展开更多
关键词 data structure open bit planning .deposit model GRAPHICS
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The Technology of Data Conversion Among Different DBMSs
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作者 孙适雨 宋瀚涛 梁允荣 《Journal of Beijing Institute of Technology》 EI CAS 1993年第1期83-89,共7页
In the application development of database,sharing information a- mong different DBMSs is an important and meaningful technical subject. This paper analyzes the schema definition and physical organization of popu- lar... In the application development of database,sharing information a- mong different DBMSs is an important and meaningful technical subject. This paper analyzes the schema definition and physical organization of popu- lar relational DBMSs and suggests the use of an intermediary schema.This technology provides many advantages such as powerful extensibility and ease in the integration of data conversions among different DBMSs etc.This pa- per introduces the data conversion system under DOS and XENIX operating systems. 展开更多
关键词 dataBASE database management system data models data structure
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Data Bucket-Based Fragment Management for Solid State Drive Storage System
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作者 Wei Jiang Jun-Long Wang +2 位作者 Jin-Yu Zhan Jing-Huan Yu Hai-Bo Hu 《Journal of Electronic Science and Technology》 CAS CSCD 2020年第4期330-340,共11页
The current storage mechanism considered little in data’s keeping characteristics.These can produce fragments of various sizes among data sets.In some cases,these fragments may be serious and harm system performance.... The current storage mechanism considered little in data’s keeping characteristics.These can produce fragments of various sizes among data sets.In some cases,these fragments may be serious and harm system performance.In this paper,we manage to modify the current storage mechanism.We introduce an extra storage unit called data bucket into the classical data manage architecture.Next,we modify the data manage mechanism to improve our designs.By keeping data according to their visited information,both the number of fragments and the fragment size are greatly reduced.Considering different data features and storage device conditions,we also improve the solid state drive(SSD)lifetime by keeping data into different spaces.Experiments show that our designs have a positive influence on the SSD storage density and actual service time. 展开更多
关键词 data structure erasing time FRAGMENT solid state driver(SSD)
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A Multilevel Secure Relation-Hierarchical Data Model for a Secure DBMS
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作者 朱虹 冯玉才 《Journal of Modern Transportation》 2001年第1期8-16,共9页
A multilevel secure relation hierarchical data model for multilevel secure database is extended from the relation hierarchical data model in single level environment in this paper. Based on the model, an upper lowe... A multilevel secure relation hierarchical data model for multilevel secure database is extended from the relation hierarchical data model in single level environment in this paper. Based on the model, an upper lower layer relationalintegrity is presented after we analyze and eliminate the covert channels caused by the database integrity.Two SQL statements are extended to process polyinstantiation in the multilevel secure environment.The system based on the multilevel secure relation hierarchical data model is capable of integratively storing and manipulating complicated objects ( e.g. , multilevel spatial data) and conventional data ( e.g. , integer, real number and character string) in multilevel secure database. 展开更多
关键词 dataBASES data structure data models secure DBMS covert channels mandatory access control POLYINSTANTIATION hierarchical classification non hierarchical category security level integrity cluster index
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Towards Efficient Security Policy Lookup on ManyCore Network Processing Platforms 被引量:1
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作者 WANG Xiang QI Yaxuan +2 位作者 WANG Kai XUE Yibo LI Jun 《China Communications》 SCIE CSCD 2015年第8期146-160,共15页
Modem network security devices employ packet classification and pattern matching algorithms to inspect packets. Due to the complexity and heterogeneity of different search data structures, it is difficult for existing... Modem network security devices employ packet classification and pattern matching algorithms to inspect packets. Due to the complexity and heterogeneity of different search data structures, it is difficult for existing algorithms to leverage modern hardware platforms to achieve high performance. This paper presents a Structural Compression (SC) method that optimizes the data structures of both algorithms. It reviews both algorithms under the model of search space decomposition, and homogenizes their search data structures. This approach not only guarantees deterministic lookup speed but also optimizes the data structure for efficient implementation oi1 many-core platforms. The performance evaluation reveals that the homogeneous data structure achieves 10Gbps line-rate 64byte packet classification throughput and multi-Gbps deep inspection speed. 展开更多
关键词 packet classification patternmatching ALGORITHMS data structures
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Framed-Quadtree Path Planning for an Underwater Vehicle with the Task of Tracking a Moving Target 被引量:1
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作者 高博 徐德民 严卫生 《Journal of Marine Science and Application》 2010年第1期27-33,共7页
An autonomous underwater vehicle (AUV) must use an algorithm to plan its path to distant, mobile offshore objects. Because of the uneven distribution of obstacles in the real world, the efficiency of the algorithm dec... An autonomous underwater vehicle (AUV) must use an algorithm to plan its path to distant, mobile offshore objects. Because of the uneven distribution of obstacles in the real world, the efficiency of the algorithm decreases if the global environment is represented by regular grids with all of them at the highest resolution. The framed quadtree data structure is able to more efficiently represent the environment. When planning the path, the dynamic object is expressed instead as several static objects which are used by the path planner to update the path. By taking account of the characteristics of the framed quadtree, objects can be projected on the frame nodes to increase the precision of the path. Analysis and simulations showed the proposed planner could increase efficiency while improving the ability of the AUV to follow an object. 展开更多
关键词 regular grid framed quadtree data structure algorithm efficiency
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Efficient XML Query and Update Processing Using A Novel Prime-Based Middle Fraction Labeling Scheme 被引量:2
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作者 Zunyue Qin Yong Tang +3 位作者 Feiyi Tang Jing Xiao Changqin Huang Hongzhi Xu 《China Communications》 SCIE CSCD 2017年第3期145-157,共13页
XML data can be represented by a tree or graph and the query processing for XML data requires the structural information among nodes. Designing an efficient labeling scheme for the nodes of Order-Sensitive XML trees i... XML data can be represented by a tree or graph and the query processing for XML data requires the structural information among nodes. Designing an efficient labeling scheme for the nodes of Order-Sensitive XML trees is one of the important methods to obtain the excellent management of XML data. Previous labeling schemes such as region and prefix often sacrifice updating performance and suffer increasing labeling space when inserting new nodes. To overcome these limitations, in this paper we propose a new labeling idea of separating structure from order. According to the proposed idea, a novel Prime-based Middle Fraction Labeling Scheme(PMFLS) is designed accordingly, in which a series of algorithms are proposed to obtain the structural relationships among nodes and to support updates. PMFLS combines the advantages of both prefix and region schemes in which the structural information and sequential information are separately expressed. PMFLS also supports Order-Sensitive updates without relabeling or recalculation, and its labeling space is stable. Experiments and analysis on several benchmarks are conducted and the results show that PMFLS is efficient in handling updates and also significantly improves the performance of the query processing with good scalability. 展开更多
关键词 XML data structure information order information information separation PMFLS labeling scheme
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