PROLOG与DBMS系统连接的实现方法

本文介绍了实现PROLOG-DBMS系统的几种方法,如:解释,编译,半解释和半编译方法.并介绍了各种方法的优点和不足,尤其是半解释方法和半编译方法的优缺点的比较.     

PROLOG—DBMS系统实现中的子句间优化技术

实用ＰＲＯＬＯＧ—ＤＢＭＳ系统实现中的首要问题是要保证系统的正确性．然而,从数据库中提取冗余数据不但严重地影响系统的效率,而且影响系统的正确性．本文所提出的子句间优化技术可以解决这一问题．因为采用这一技术可以保证仅从数据库中提取有用事实并且没有任何元组多于一次被提取．     

PROLOG—DBMS耦合：半解释半编译的混合式方法

本文介绍了一种混合式 Prolog-DBMS 耦合技术,它既能保持解释方法和编译方法的优点,又能克服其缺点。这种技术使得随时使用关系数据库算子(比如连接算子)成为可能,同时避免了无用数据(即归结过程中不用的数据)的加载.最后,“历史”管理机制保证了同一数据不会被多次加载。     

基于Search并行的顺序PROLOG系统的设计与分析

克服PROLOG系统低效的重要途径是减少/加快数据库搜索及项合一操作以及减少/加快回溯操作。本文给出一种多处理机上的基于SEARCH并行的顺序PROLOG解释方法,指出它在克服搜索/合一代价高这一方面的优点并分析通讯对于系统性能的影响。     

支持无共享结构的并行DBMS软件结构

文中介绍并行数据库系统ＰＡＲＯ的体系结构设计，它能很好地支持无共享结构的并行计算机。并描述该系统的软件结构，说明如何在这一软件结构下开发事务间并行性、查询内的操作间和操作内并行性。     

基于DBMS扩展的数据库加密系统的设计与实现

如何安全而有效地对数据库信息进行加密保护是目前迫切需要解决的课题.本文提出一种基于DBMS扩展的数据库加密系统,系统通过对DBMS进行扩展实现加解密功能,并向用户提供可选择的字段加密.系统透明性好,并且较好地解决了不同用户对数据加密的不同要求,具有一定的实际意义.     

用表结合的数据库—PROLOG系统

本文介绍了用表结构将能够有效地管理很大的数据库,但缺乏推理能力的关系数据库管理系统与具有很强的演绎推理能力,但缺乏管理大量数据功能的PROLOG系统结合在一起,形成演绎数据库或专家数据库系统的原理与方法。     

PROLOG语言在计算机网络环境下的开发与应用

本文讨论了分布式计算机系统中进程通信的一种机制──远程过程调用（ＲＰＣ）的设计与实现。在此基础上，将ＲＰＣ机制扩充到ＰＲＯＬＯＧ语言中，使该语言具有网络通信能力，初步实现了计算机局域网络环境下ＰＲＯＬＯＧ语言的应用，为分布式专家系统的程序实用于网络探索新路。     

一种分布式DBMS故障恢复技术

本文设计并实现了一种新的分布式数据库管理系统故障恢复技术，即基于后映象文件，事务私有更新区的故障恢复技术；详细介绍了其基本数据结构及二段式提交算法，回滚处理及恢算法。     

Using an extended PROLOG to solve the lion and unicorn puzzle

This paper presents a general approach to solve a constraint satisfaction problem over a finite domain by reducing it to unification in finite algebras. The lion and unicorn puzzle is considered as a constraint satisfaction problem and its implementation in an extended PROLOG is described.     

DBMS多线索技术及其实现

本文提出了一种基于消息通信的多线索ＤＢＭＳ体系结构，详细介绍了多线索ＤＢＭＳ技术在ＡＴ＆ＴＵＮＩＸ４．２环境下的实现策略。     

Database Allocation Strategies for Parallel BLAST Evaluation on Clusters

In this work we investigate the parallel evaluation of BLAST, the most popular tool for comparing biological sequences. Our goal is to study database distribution issues that, besides workload balancing, could improve the performance of a set of BLAST processes running in a workstation cluster. We consider different partitioning strategies within actual BLAST executions against a few relevant molecular databases. We have implemented multiple databases and input sequence configurations and show that there are many important parameters, such as the fragment generation method and sequence similarities, that must be taken into account in order to make full use of such parallel environment.     

基于MPI的并行计算集群通信及应用

对能有效解大型稀疏矩阵方程的LSQR串行算法进行了并行化分析,并应用可移植消息传递标准MPI的集群通信机制在分布式存储并行系统上设计和实现了LSQR并行算法,该并行算法和程序在地震表层模型层析反演中得到了有效的应用。     

Data structures and DBMS for computer-aided design systems

The structures for the storage of data in CAD systems influence to a large extent the effectiveness of the system. This paper reviews the wide range of data structures and database management systems (DBMS) available for structuring CAD data. Examples of basic data types are drawn from the MODULA-2 language. The relationship between these basic data types, their composite structures and the classical data models (on which many DBMS are based) is discussed, and the limitations of existing DBMS in modelling CAD data highlighted. A set of requirements for CAD database management systems is drawn up and the emerging role of product models (which seek to encapsulate the totality of data elements required to define fully an engineering artefact) is explored.     

并行仿真技术综述

该文从并行仿真框架、仿真任务的分配、仿真实现以及仿真策略等几个方面论述了当前并行仿真技术的发展状况,然后对并行仿真技术的前景加以展望。     

A Fast and Accurate Technique for Mapping Parallel Applications on Stream-Oriented MPSoC Platforms with Communication Awareness

The problem of allocating and scheduling precedence-constrained tasks on the processors of a distributed real-time system is NP-hard. As such, it has been traditionally tackled by means of heuristics, which provide only approximate or near-optimal solutions. This paper proposes a complete allocation and scheduling framework, and deploys an MPSoC virtual platform to validate the accuracy of modelling assumptions. The optimizer implements an efficient and exact approach to the mapping problem based on a decomposition strategy. The allocation subproblem is solved through Integer Programming (IP) while the scheduling one through Constraint Programming (CP). The two solvers interact by means of an iterative procedure which has been proven to converge to the optimal solution. Experimental results show significant speed-ups w.r.t. pure IP and CP exact solution strategies as well as high accuracy with respect to cycle-accurate functional simulation. Two case studies further demonstrate the practical viability of our framework for real-life applications.     

工件工序可并行的作业车间调度模型与求解

针对传统作业车间调度模型没有考虑工件工序存在并行性的不足,提出一种以最小化完工时间为目标的工件工序可并行作业车间调度模型,且在模型中考虑了工序加工设备柔性;设计了基于遗传算法的调度算法,其中染色体编码采用分段编码方式,并提出一种适用于工件工序存在并行性的染色体解码方法.实验结果表明,文中算法能够有效地解决工件工序可并行的作业车间调度问题.