检索结果-内蒙古大学图书馆

Indexing Fuzzy Spatiotemporal Data for Efficient Querying: A Meteorological Application

IEEE TRANSACTIONS ON FUZZY SYSTEMS 2015年第5期23卷 1399-1413页

作者： Sozer, Aziz Yazici, Adnan Oguztuzun, Halit Middle E Tech Univ Dept Comp Engn TR-06800 Ankara Turkey

Spatiotemporal data, in particular fuzzy and complex spatial objects representing geographic entities and relations, is a topic of great importance in geographic information systems and environmental data management systems. For database researchers, modeling and designing a database of fuzzy spatiotemporal data and querying such a database efficiently have been challenging issues due to complex spatial features and uncertainty involved. This paper presents an integrated approach to modeling, indexing, and efficiently querying spatiotemporal data related to fuzzy spatial and complex objects and spatial relations. As our case study, we design and implement a meteorological database application that involves fuzzy spatial and complex objects, and a spatiotemporal index structure, and supports various types of spatial queries including fuzzy spatiotemporal queries. Our implementation is based on an intelligent database system architecture that combines a fuzzy object-oriented database with a fuzzy knowledge base.

关键词： Complex spatial object fuzzy object knowledge base meteorological database application object-oriented databases spatiotemporal data spatiotemporal indexing and querying

来源：评论

学校读者我要写书评

暂无评论

Optimizing object queries using an effective calculus

引用

ACM TRANSACTIONS ON DATABASE SYSTEMS 2000年第4期25卷 457-516页

作者： Fegaras, L Maier, D Univ Texas Dept Comp Sci & Engn Arlington TX 76019 USA Oregon Grad Inst Sci & Technol Dept Comp Sci & Engn Beaverton OR 97006 USA

object-oriented databases (OODBs) provide powerful data abstractions and modeling facilities, but they generally lack a suitable framework for query processing and optimization. The development of an effective query optimizer is one of the key factors for OODB systems to successfully compete with relational systems, as well as to meet the performance requirements of many nontraditional applications. We propose an effective framework with a solid theoretical basis for optimizing OODB query languages. Our calculus, called the monoid comprehension calculus, captures most features of ODMG OQL, and is a good basis for expressing various optimization algorithms concisely. This article concentrates on query unnesting (also known as query decorrelation), an optimization that, even though it improves performance considerably, is not treated properly (if at all) by most OODB systems. Our framework generalizes many unnesting techniques proposed recently in the literature, and is capable of removing any form of query nesting using a very simple and efficient algorithm. The simplicity of our method is due to the use of the monoid comprehension calculus as an intermediate form for OODB queries. The monoid comprehension calculus treats operations over multiple collection types, aggregates, and quantifiers in a similar way, resulting in a uniform method of unnesting queries, regardless of their type of nesting.

关键词： experimentation performance object-oriented databases nested relations query decorrelation query optimization

来源：评论

学校读者我要写书评

暂无评论

ADOME: An advanced object modeling environment

引用

IEEE TRANSACTIONS ON KNOWLEDGE AND DATA ENGINEERING 1998年第2期10卷 255-276页

作者： Li, Q Lochovsky, FH Hong Kong Polytech Univ Dept Comp Kowloon Peoples R China Hong Kong Univ Sci & Technol Dept Comp Sci Kowloon Peoples R China

ADOME, which stands for ADvanced object Modeling Environment is an approach to integrating data and knowledge management based on object-oriented technology. Next generation information systems will require more flexible data modeling capabilities than those provided by current object-oriented DBMSs. In particular, integration of data and knowledge management capabilities will become increasingly important. In this context, ADOME provides versatile role facilities that serve as "dynamic binders" between data objects and production rules, thereby facilitating flexible data and knowledge management integration. A prototype that implements this mechanism and the associated operators has been constructed on top of a commercial object-oriented DBMS and a rule-base system.

关键词： object modeling knowledge semantics dynamic roles object-oriented databases next-generation information systems

来源：评论

学校读者我要写书评

暂无评论

Implementation of a dynamic scheduler for apparel computer integrated manufacturing systems

引用

JOURNAL OF INTELLIGENT MANUFACTURING 1997年第2期8卷 67-81页

作者： Gracanin, D Valavanis, KP Smith, SA Williams, T Steward, A Apparel-CIM Center The University of Southwestern Louisiana Lafayette USA

A major problem faced by the typical apparel manufacturer in day-to-day operations is the need for an effective scheduler to determine actions required because of operator and/or machine non-performance. The dynamic resource allocation system (DRAS) scheduler described in this paper is the natural outgrowth of previously funded research related to the design, development, technology transfer and installation of a CIM system in an apparel plant. The already developed CIM system provides a way for the DRAS scheduler (described in this paper) to change a production process dynamically. The implementation and modeling approach of the scheduler is described. The underlying system model is based on Petri nets and object-oriented databases. Petri nets provide a dynamic model of the CIM system, while object-oriented databases provide necessary information about system components and overall system activity. The data from the CIM system is used by the scheduler in the simulation mode. The daily production plan is used as a guideline to determine how to react to and correct production problems.

关键词： computer integrated manufacturing (CIM) scheduling resource allocation Petri nets object-oriented databases

来源：评论

学校读者我要写书评

暂无评论

A cost-based buffer replacement algorithm for object-oriented database systems

引用

INFORMATION SCIENCES 2001年第1-4期138卷 99-117页

作者： Park, CM Whang, KY Lee, JJ Song, IY Korea Adv Inst Sci & Technol Adv Informat Technol Res Ctr AITrc Dept Comp Sci Taejon 305701 South Korea Drexel Univ Coll Informat Sci & Technol Philadelphia PA 19104 USA

Many object-oriented database systems manage object buffers to provide fast access to objects. Traditional buffer replacement algorithms based on fixed-length pages simply assume that the cost incurred by operating a buffer is proportional to the number of buffer faults. However, this assumption no longer holds in an object buffer where objects are of variable-lengths and the cost of replacing an object varies for each object. In this paper, we propose a cost-based replacement algorithm for object buffers. The proposed algorithm replaces the objects that have minimum costs per unit time and unit space. The cost model extends the previous page-based one to include the replacement costs and the sizes of objects. The performance tests show that the proposed algorithm is almost always superior to the LRU-2 algorithm and, when significant replacement cost is involved, is more than twice as fast. (C) 2001 Published by Elsevier Science Inc.

关键词： object-oriented databases databases MANAGEMENT ALGORITHMS MATHEMATICAL models

来源：评论

学校读者我要写书评

暂无评论

An object-oriented model for conceptual ship design supporting case-based design

引用

MARINE TECHNOLOGY AND SNAME NEWS 2003年第3期40卷 158-167页

作者： Delatte, B Butler, A Louisiana Tech Univ Ruston LA 71270 USA

Design of ships, including warships such as submarines, is normally begun with a feasibility study. The feasibility study provides initial proof of concept and becomes a basis for further efforts. Because time and information for analysis is usually limited, historical design data is typically used to help with the generation of conceptual designs. To support automation of design efforts under these circumstances, adaptation and reuse of earlier designs represents a very useful paradigm. This paper presents a data storage system to store historical design data for subsequent reuse in conceptual design. The database is designed to support case-based reasoning and other similar processes in which recall of past solutions becomes a basis for adaptation to form a new solution. The stored data support conceptual design for a submarine or ship using previous design information. The data involve complex geometric information, and an object-oriented database system is presented. The object-oriented database stores complex information in a useful format for recall on a "similar to" basis. This architecture allows case-based reasoning and other recall-based systems to utilize feature-based design information based on similarity to new requirements. To avoid using information that is sensitive and/or classified, this system is demonstrated using unclassified commercial submarine and Maritime Administration ship data. Experiences with two generations of prototype software are discussed, and conclusions about system utility are reached.

关键词： conceptual Basis Ship design information proof of concept object oriented modeling WARSHIP Submarine Conceptual design Software prototyping DATA STORAGE SYSTEMS design data object-oriented databases Ships Case Based Reasoning

来源：评论

学校读者我要写书评

暂无评论

Applicability of genetic algorithms to optimal evaluation of path predicates in object-oriented queries

引用

INFORMATION PROCESSING LETTERS 1996年第3期58卷 123-128页

作者： Seo, SK Lee, YJ KOREA ADV INST SCI & TECHNOL DEPT COMP SCIYUSEONG KUTAEJON 305701SOUTH KOREA

The optimization of object-oriented queries containing path predicates is addressed. The problem is formulated and the genetic search strategies are applied to the query optimization problem . Experiment results show that the problem formulation suits well to genetic algorithm's (GA) behavior. GA worked efficiently both in the solution quality and execution time, showing its feasibility for use in optimization problems of database systems.

关键词： algorithms databases object-oriented databases query optimization genetic algorithms

来源：评论

学校读者我要写书评

暂无评论

Reactive processing in ADOME-II: an extensible approach

引用

INFORMATION SCIENCES 2003年第4期149卷 277-309页

作者： Li, Q Chan, LC City Univ Hong Kong Dept Comp Engn & Informat Technol Kowloon Hong Kong Peoples R China Hong Kong Jockey Club Kowloon Hong Kong Peoples R China

A new approach for supporting reactive cap-ability is described in the context of an advanced object-oriented database system called ADOME-II. Besides having a rich set of pre-defined composite event expressions and a-well-defined execution model, ADOME-II supports an extensible approach to reactive processing so as to be able to gracefully accommodate. dynamic applications' requirements. In this approach, production rules combined with methods are used, as a unifying mechanism, to. process rules, to enable incremental detection of composite events, and to allow new composite event expressions to be introduced into the system declaratively. This allows the definition of new production rules each time an extension of the model takes place. Methods of supporting new composite event expressions are described, and comparisons with other relevant approaches are also conducted. A prototype of ADOME-II has been constructed, which has as its implementation base an ordinary (passive) OODBMS and a production rule base system. (C) 2002 Elsevier Science Inc. All rights reserved.

关键词： reactive processing object-oriented databases event expression and execution model production rules extensible approach

来源：评论

学校读者我要写书评

暂无评论

Tools for support of automata-based programming

引用

PROGRAMMING AND COMPUTER SOFTWARE 2007年第6期33卷 343-355页

作者： Gurov, V. S. Mazin, M. A. Narvsky, A. S. Shalyto, A. A. eVelopers Corp St Petersburg 197101 Russia St Petersburg State Univ Informat Technol Mech & St Petersburg 197101 Russia

A method for designing and implementing reactive object-oriented programs with explicit emphasis of states is suggested. The method relies on the automata-based programming (SWITCH-technology) and the UML notation. Th... 详细信息

关键词： object-oriented methods (Computer science) object-oriented databases databases MACHINE theory COMPUTER programming

来源：评论

学校读者我要写书评

暂无评论

The building blocks for specifying communication behavior of complex objects: An activity-driven approach

引用

ACM TRANSACTIONS ON DATABASE SYSTEMS 1996年第2期21卷 157-207页

作者： Liu, L Meersman, R FREE UNIV BRUSSELS DEPT COMP SCI B-1050 BRUSSELS BELGIUM

Communication behavior represents dynamic evolution and cooperation of a group of objects in accomplishing a task. It is an important feature in object-oriented systems. We propose the concept of activity as a basic building block for declarative specification of communication behavior in object-oriented database systems, including the temporal ordering of message exchanges within object communication and the behavioral relationships between activity executions. We formally introduce two kinds of activity composition mechanisms: activity specialization and activity aggregation for abstract implementation of communication behavior. The former is suited for behavioral refinement of existing activities into specialized activities. The latter is used for behavioral composition of simpler activities into complex activities, and ultimately, into the envisaged database system. We use first-order temporal logic as an underlying formalism for specification of communication constraints. The well-known Air-traffic-control case is used as a running example to highlight the underlying concepts, to illustrate the usefulness, and to assess the effectiveness of the activity model for declarative specification of communication behavior in the relevant universe of discourse. We also propose a methodological framework for integrating activity schema with entity schema in an object-oriented design environment.

关键词： activity aggregation activity patterns activity specialization communication behavior first-order temporal logic object-oriented databases synchronization schemes

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：