Computer Languages最新文献_第4页

Countdown Y2K; Peter de Jager, Richard Bergeon. John Wiley & Sons, Inc. ISBN: 0-471-32734-4. 倒计时Y2K;Peter de Jager, Richard Bergeon。约翰威利父子公司ISBN: 0-471-32734-4。

Computer Languages Pub Date : 1999-07-01 DOI: 10.1016/S0096-0551(99)00008-9

R.S Ledley

引用次数: 0

Extending temporal query languages to handle imprecise time intervals 扩展时态查询语言以处理不精确的时间间隔

Computer Languages Pub Date : 1999-04-01 DOI: 10.1016/S0096-0551(99)00003-X

M.A. Bassiouni, M. Llewellyn

{"title":"Extending temporal query languages to handle imprecise time intervals","authors":"M.A. Bassiouni, M. Llewellyn","doi":"10.1016/S0096-0551(99)00003-X","DOIUrl":"10.1016/S0096-0551(99)00003-X","url":null,"abstract":"<div><p>Previous work on temporal and historical databases has been mainly based on the assumption that the time intervals of temporal attributes and the start/finish points of modeled events are precisely known. In many real life situations, however, the time boundary of events and the duration of entity relationships may not be exactly known. Modeling these situations and providing a way to write queries dealing with time impreciseness represents a useful extension currently lacking in existing/proposed temporal database systems. In this paper, we discuss the problem of handling time impreciseness in temporal databases and present three models for the representation of imprecise time intervals. We illustrate the basic idea and motivation of each model, its underlying logic, tradeoffs, and important properties. We also propose query language extensions that can enrich the user interface with capabilities to formulate queries dealing with time impreciseness. Extensions to existing query constructs at both the transaction level and the operator level are presented. New operators related to time impreciseness are also presented. The models and extensions discussed in this paper enrich the flexibility of temporal databases and can be used to help users obtain more meaningful replies for their temporal queries.</p></div>","PeriodicalId":100315,"journal":{"name":"Computer Languages","volume":"25 1","pages":"Pages 39-54"},"PeriodicalIF":0.0,"publicationDate":"1999-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/S0096-0551(99)00003-X","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86275241","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

A sketch-based technique for the derivation of self-interpreters 一种基于草图的自解释器派生技术

Computer Languages Pub Date : 1999-04-01 DOI: 10.1016/S0096-0551(99)00004-1

A.C. Reeves , C. Rattray

引用次数: 1

New mechanisms for invocation handling in concurrent programming languages1 并发编程语言中调用处理的新机制1

Computer Languages Pub Date : 1998-12-01 DOI: 10.1016/S0096-0551(98)00010-1

M Chung , R.A Olsson

引用次数: 3

Index 指数

Computer Languages Pub Date : 1998-12-01 DOI: 10.1016/S0096-0551(99)00006-5

引用次数: 0

Index 指数

Computer Languages Pub Date : 1998-12-01 DOI: 10.1016/S0096-0551(99)00005-3

引用次数: 0

Active objects as atomic control structures in BaLinda K 作为原子控制结构的活动对象

Computer Languages Pub Date : 1998-12-01 DOI: 10.1016/S0096-0551(98)00011-3

C.K. Yuen , M.D. Feng

引用次数: 1

Grammar partitioning and modular deterministic parsing1 语法划分和模块化确定性解析1

Computer Languages Pub Date : 1998-12-01 DOI: 10.1016/S0096-0551(98)00012-5

Stefano Crespi Reghizzi, Giuseppe Psaila

引用次数: 5

Design and implementation of a parallel cellular language for MIMD architectures 一种用于MIMD体系结构的并行细胞语言的设计与实现

Computer Languages Pub Date : 1998-10-01 DOI: 10.1016/S0096-0551(98)00007-1

Stéphane Vialle , Yannick Lallement , Thierry Cornu

引用次数: 5

Preference logic grammars 偏好逻辑语法

Computer Languages Pub Date : 1998-10-01 DOI: 10.1016/S0096-0551(98)00008-3

Bharat Jayaraman , Kannan Govindarajan , Surya Mantha

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引用次数: 16