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1.
H. S. M. Kruijer 《Software》1982,12(5):445-454
This paper presents a medium-sized operating system written in Concurrent Pascal, thereby describing further experience with this language and giving further indications of its scope. The operating system was developed to support an application in the area that is usually termed ‘commercial’ or ‘administrative’. Both the functional capabilities and the structure of the operating system are described, with emphasis on its facilities for data file management, and its size and performance are given. A secondary theme of the paper is the relationship of the operating system's qualities to the properties and facilities of the programming language Concurrent Pascal used for its development.  相似文献   

2.
D-Tuili,having been implemented on microcompute network,is a distributed logical reasoning programming language.D-Tuili supports parallel programming on the language level,and couples loosely with the distributed database management system,so data in distributed databases can be used in the distributed logic programs.In this paper,we mainly introduce the components of D-Tuili used to design distributed logic programs.Furthermore,the main principles to implement D-Tuili and the main technologies adopted in the implemented system of D-Tuili are described.  相似文献   

3.
TGMS (tiered geometric modelling system) is an experimental system intended to reduce the difficulty and cost of developing new solid modelling applications while preserving investment in an existing, time-tested, solid modeller. The application developer writes programs in the TGMS language, which consists of a base language augmented by data types (classes) for geometry. The base programming language is AML/X, an object-oriented language intended for use in design and manufacturing applications. Solid modelling is done using an interface to GDP (geometric design processor), an existing, production-quality solid modelling system. TGMS shows how a system written in a non-object-oriented language can be used as a base for an object-oriented application programming environment. This paper presents the design of TGMS and discusses important aspects of its implementation. The TGMS language defines classes and methods that provide an interface to functions and data represented in a non-object-oriented language. To implement TGMS, issues related to communication, storage management and consistency were addressed. These, and other, implementation issues are discussed. The paper includes sample programs and a summary of feedback from TGMS users. It concludes that the use of object-oriented programming for geometry has many benefits, and that an object-oriented system can be built on top of a non-object-oriented system at less cost than building the equivalent object-oriented system from scratch.  相似文献   

4.
The Pegasus heterogeneous multidatabase system   总被引:1,自引:0,他引:1  
Pegasus, a heterogeneous multidatabase management system that responds to the need for effective access and management of shared data across in a wide range of applications, is described. Pegasus provides facilities for multidatabase applications to access and manipulate multipole autonomous heterogeneous distributed object-oriented relational, and other information systems through a uniform interface. It is a complete data management system that integrates various native and local databases. Pegasus takes advantage of object-oriented data modeling and programming capabilities. It uses both type and function abstractions to deal with mapping and integration problems. Function implementation can be defined in an underlying database language or a programming language. Data abstraction and encapsulation facilities in the Pegasus object model provide an extensible framework for dealing with various kinds of heterogeneities in the traditional database systems and nontraditional data sources  相似文献   

5.
Exception handling is widely regarded as a necessity in programming languages today and almost every programming language currently used for professional software development supports some form of it. However, spreadsheet systems, which may be the most widely used type of “programming language” today in terms of number of users using it to create “programs” (spreadsheets), have traditionally had only extremely limited support for exception handling. Spreadsheet system users range from end users to professional programmers and this wide range suggests that an approach to exception handling for spreadsheet systems needs to be compatible with the equational reasoning model of spreadsheet formulas, yet feature expressive power comparable to that found in other programming languages. We present an approach to exception handling for spreadsheet system users that is aimed at this goal. Some of the features of the approach are new; others are not new, but their effects on the programming language properties of spreadsheet systems have not been discussed before in the literature. We explore these properties, offer our solutions to problems that arise with these properties, and compare the functionality of the approach with that of exception handling approaches in other languages  相似文献   

6.
PRISMA/DB是一并行的主存关系数据库管理系统。其设计思想主要有两个:第一,将整个数据库存入主存从而获得高性能,第二,系统使用一种面向对象的程序设计语言以模块方式实现,使得这种灵活的组织结构适应于功能和性能方面的分析和试验,目前其原型系统已实现,运行在一个具有100个结点的多处理机上。本文将其设计和实现细节作一初步介绍。  相似文献   

7.
A program language can be defined as the language in which computer programs are written, and a programming language as the language used by the programmer to create programs. This paper presents the design of an interactive program development system which uses Pascal as both program and programming language. Principal properties of the system are a complete immediate syntax check, a program-structure oriented editor, incremental compiling techniques, and interactive interpretation and debugging of programs. The syntax check is split into three phases, and the user can change the degree of check wanted. After a change of the program only part of it is recompiled, and only necessary phases of the compiling process are performed.  相似文献   

8.
本文对LonWorks网络管理系统的结构与功能设计进行了探讨,并介绍在VB环境下调用LCA对象提供的属性、方法及事件实现网络管理系统软件的方法。  相似文献   

9.
We investigate the issue of designing a kernel programming language for mobile computing and describe KLAIM, a language that supports a programming paradigm where processes, like data, can be moved from one computing environment to another. The language consists of a core Linda with multiple tuple spaces and of a set of operators for building processes. KLAIM naturally supports programming with explicit localities. Localities are first-class data (they can be manipulated like any other data), but the language provides coordination mechanisms to control the interaction protocols among located processes. The formal operational semantics is useful for discussing the design of the language and provides guidelines for implementations. KLAIM is equipped with a type system that statically checks access right violations of mobile agents. Types are used to describe the intentions (read, write, execute, etc.) of processes in relation to the various localities. The type system is used to determine the operations that processes want to perform at each locality, and to check whether they comply with the declared intentions and whether they have the necessary rights to perform the intended operations at the specific localities. Via a series of examples, we show that many mobile code programming paradigms can be naturally implemented in our kernel language. We also present a prototype implementation of KLAIM in Java  相似文献   

10.
医学标准化组织标本库管理系统的设计和实现   总被引:1,自引:0,他引:1  
概括了标本库管理相关背景,根据实际情况,确定了标准化组织标本库管理系统的设计方案。采用WWW技术与传统的Client/Server相结合的三层体系结构,确定了相应的技术方案:采用数据库SQLServer平台,使用VC 语言,应用PHP编程。介绍了系统的各个功能模块极其相应的功能,并对系统开发过程中使用的关键技术——数据字典的实现、图像采集技术以及系统的安全机制进行了详细的介绍。  相似文献   

11.
A proof system for a shared dataspace programming notation called Swarm (a programming logic similar in style to that of UNITY) is specified. Relevant aspects of the Swarm language and model are overviewed. To illustrate the proof system, the Swarm logic is used to verify the correctness of a program for labeling connected equal-intensity regions of a digital image. Like UNITY, the Swarm proof system uses an assertional programming logic which relies upon proof of programwide properties, e.g. global invariants and progress properties. The Swarm logic is defined in terms of the same logical relations as UNITY (unless, ensures, and leads-to), but several of the concepts are reformulated to accommodate Swarm's distinctive features  相似文献   

12.
Memory reallocation is used to construct a run-time data structure for fast/efficient storage of information during collection and analysis. The data structure presented uses dynamic memory but does not require the use of pointers to link nodes of information together. It allows for simple and efficient access to data via array indexing rather than through the use of lists or tree structures and it provides flexibility for competing storage requirements that are determined dynamically. The data structure is developed in the C programming language and a suite of ANSI standard C subroutines that make up a run-time data structure management system is provided.  相似文献   

13.
We describe a computer-assisted data collection system developed for a multicenter cohort study of American Indian and Alaska Native people. The study computer-assisted participant evaluation system or SCAPES is built around a central database server that controls a small private network with touch screen workstations. SCAPES encompasses the self-administered questionnaires, the keyboard-based stations for interviewer-administered questionnaires, a system for inputting medical measurements, and administrative tasks such as data exporting, backup and management. Elements of SCAPES hardware/network design, data storage, programming language, software choices, questionnaire programming including the programming of questionnaires administered using audio computer-assisted self-interviewing (ACASI), and participant identification/data security system are presented. Unique features of SCAPES are that data are promptly made available to participants in the form of health feedback; data can be quickly summarized for tribes for health monitoring and planning at the community level; and data are available to study investigators for analyses and scientific evaluation.  相似文献   

14.
This article first details the development of an integrated modelling system (Flow And Solute Transport in Estuaries and Rivers), which is capable of predicting water elevations, velocities and solute and sediment concentration distributions in well-mixed rivers or narrow estuaries. The model comprises hydrodynamic and solute transport solvers, a user-friendly graphical interface—including data management and storage tools—and graphic and tabular reporting facilities. The program, initially written in Fortran, is a numerical modelling program which deploys highly accurate numerical schemes to solve the hydrodynamic and solute transport equations. This model has recently been modified to include a graphical user interface based on an object-oriented methodology, and implemented using the Visual Basic programming language. Details are given herein of the procedures used to combine the Fortran program with a Windows-based programming language, namely Visual Basic. Particular emphasis has been focused on the construction of the interface for unsteady free-surface flow problems. An example application of the model is cited to illustrate the data management capabilities and accuracy of the model when applied to real hydroenvironmental projects.  相似文献   

15.
Goedel语言是一种说明性逻辑程序设计语言。该语言基于一阶逻辑,引入了一个多态多类的类型系统和多种新的语言成分,支持抽象数据类型和模块化程序设计等技术,语言本身也具有很强的说明性语义。详细介绍了Goedel语言的类型系统及其构造,对在逻辑程序设计语言中引入类型系统的作用进行了一些深入的分析和讨论。  相似文献   

16.
17.
Gal  A. Etzion  O. 《Computer》1995,28(1):28-38
A new model with invariant-based language effectively handles data-driven rules in databases and uses the rules' inherent semantic properties and supporting mechanisms to meet high-level language requirements. It is an extension of the basic PARDES model developed by Opher Etzion in 1990 to support derivations and integrity constraints in databases. The model's invariant-based language, unlike other programming languages, can follow data-driven rules' semantic properties. Such rules are activated by modifications of data items in a database, and they play an important role in many applications that maintain complex relationships between data items or interdependencies between parts of the database. Applications include expert systems, real-time databases, simulations, and decision-support systems. The authors present requirements for choosing an adequate programming style that uses data-driven rules. These requirements are based on software-engineering criteria such as compatibility with a high-level language and verifiability of the rule language. The authors show that contemporary database programming styles fail to meet these requirements, and they present the invariant-based language as a viable solution  相似文献   

18.
A general framework for network aware programming is presented that consists of a language for programming mobile applications, a logic for specifying properties of the applications and an automatic tool for verifying such properties. The framework is based on X-KLAIM, eXtended KLAIM, an experimental programming language specifically designed to program distributed systems composed of several components interacting through multiple tuple spaces and mobile code. The proposed logic is a modal logic inspired by Hennessy-Milner logic and is interpreted over the same labelled structures used for the operational semantics of X-KLAIM. The automatic verification tool is based on a complete proof system that has been previously developed for the logic.  相似文献   

19.
One of the well-known properties of software systems is that they are subject to changes. Incremental software development enables making such program changes in a non-destructive manner. In the area of programming language definition the language designer/implementer wants to include new language features incrementally as the programming language evolves. In the paper our approach to incremental programming language development is presented. The proposed approach has been successfully used in the development of real programming languages, which confirms feasibility in practice.  相似文献   

20.
周鹏 《微处理机》2014,(4):68-70
事件日志作为一种重要的系统管理工具,主要用于监视系统运行情况、查找系统故障根源和分析软件的执行流程等。对软件开发者而言,有必要从编程角度分析 Windows7系统的事件日志架构体系。简要介绍 NET Framework 一个重要的事件日志类 EventLog,以及使用 EventLog 类和 C ++/CLI 语言实现事件日志创建、写入和删除的编程方法。  相似文献   

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