物流信息系统中设计模式的应用

随着信息系统的不断发展,客户对软件系统提出了更高的要求。由于软件开发固有的复杂性、软件实现的不易复制性,软件的生产过程面临许多问题。设计模式提供了对问题簇的设计精良的解决方案。文中通过在物流信息系统中引入设计模式,具体分析了三种代表性的设计模式在物流信息系统中的应用,证明了模式设计的引入有助于提高软件的可复用性、可维护性以及稳定性和安全性。     

物流信息系统中设计模式的应用

随着信息系统的不断发展，客户对软件系统提出了更高的要求。由于软件开发固有的复杂性、软件实现的不易复制性，软件的生产过程面临许多问题。设计模式提供了对问题簇的设计精良的解决方案。文中通过在物流信息系统中引入设计模式，具体分析了三种代表性的设计模式在物流信息系统中的应用，证明了模式设计的引入有助于提高软件的可复用性、可维护性以及稳定性和安全性。     

可复用数字图像处理工具箱的设计与实现

设计模式是可复用面向对象设计的基础，该文采用了适配器、中介者、桥接等模式设计了一个可复用的数字图像处理工具箱，介绍了一个用外观模式对工具箱进行二次开发的实例。并通过比较展示了引入模式设计的优点。     

基于安全模式的软件安全设计研究

当前软件开发过程中往往忽略了安全性的保障,本研究提出了一种基于安全模式的软件安全设计方法,将安全工程学科中的风险管理过程和POAD(面向模式的分析和设计)方法过程进行结合,通过加入安全设计模式重构系统的整体架构提升软件设计环节的安全性。     

一种松耦合高复用MVC模式的Web分页实现

MVC设计模式下常见Web分页方案存在一些不足,针对降低耦合性和提高复用性提出了改进方案,并通过在数据层引入Hibernate框架,服务层引入Bridge桥接模式,表示层引入Struts框架对改进方案加以实现。     

组态软件设计中的模式研究

工业组态软件的设计是复杂的,为了设计出灵活的、可扩展性好、易维护的工业组态软件,在采用面向对象的软件设计时,引入了设计模式的概念,这些模式来源于众多设计者多年的面向对象的设计成果,这些模式的恰当运用解决了很多组态软件设计问题,使程序优雅而灵活,体现了面向对象编程的优越性。     

设计模式在数据库浏览系统中的应用

本文采用设计模式中的桥接模式、抽象工厂模式和单件模式设计并实现一个数据库浏览系统,讨论了设计模式给软件设计带来的优越性.     

设计模式在图形处理软件中的应用

介绍了设计模式的含义,说明了图形处理软件的体系结构,并论述了桥接模式、组合模式、代理模式、命令模式、观察者模式和迭代器在图形处理软件中的应用.     

设计模式在GIS软件开发中的应用研究

详细论述了组合(Composite)、桥接(Bridge)、观察者(Observer)、命令(Command)、外观(Facade)、装饰(Decora-tor)六种设计模式在GIS软件开发中的应用。旨在促使GIS开发中注重设计模式,努力发现、归纳并应用设计模式,实现软件设计的重用,提高GIS软件的质量和开发效率。     

一种基于桥接模式的软件设计方法和实例分析

桥接模式是软件开发中经常应用到的设计模式,它将软件的抽象部分与实现部分分离,使它们都可以独立地变化。以铁路沉降变形数据分析处理为例,详细介绍桥接模式的概念、使用场合及其效果,给出.Net环境下运用桥接模式实现铁路变形数据处理分析的实例,并对桥接模式在实例中的应用代码进行分析。     

基于模式的商业智能系统设计

首先分析了软件体系结构、设计模式与软件设计之间的关系。以复用专家的成功设计经验为出发点,试图通过软件体系结构和设计模式在需求分析与软件系统设计之间建立一条顺畅的途径,简化设计、提高质量,满足软件系统的功能性需求和非功能性需求。最后给出商业智能系统设计模型。     

Gas burner control using microprocessors

The application of microprocessors to the direct supervision of industrial gas burners offers several advantages over existing technology. The achievement of adequate safety standards poses particular design problems which are not conveniently solved by multiple-channel redundancy. A hierarchical multiple-burner control system is described in which hardware and software combine to achieve required levels of safety. The architecture permits comprehensive facilities for reading out information on the state of the various burners, both locally and at a remote location. In hazardous or noisy environments a fibre-optic link can be used for remote communication.     

Quality assurance and testing for safety systems

In this paper we identify special quality assurance and test requirements of software for safety systems and show that even the best currently available practices meet these requirements only at very high cost and by application of empirical rather than technically rigorous criteria. Redundancy can help but is expensive and the reduction in failure probability due to software redundancy is uncertain. We identify a qualitative approach to test data interpretation, particularly the examination of rare events in the conditions that precipitated an observed failure, as a possible avenue for a more economical reliability assessment. This can be used as an alternative or as a supplement to redundancy for meeting the reliability requirements for software in safety systems. Further research in this area is recommended.     

起落架多冗余度收放控制器设计

起落架收放系统对大型客机的安全性至关重要,其中起落架收放控制和指示子系统的安全性以及指示的正确性,对减少故障的发生和提高维修性具有重要意义。文中设计了一种采用双-双余度结构的起落架收放控制器,将有中心裁决冗余与无中心裁决冗余相结合,并同时采用了非相似余度设计以及各种软硬件错误检测,极大地提高了系统的可靠性,实际运行证明此设计是十分可靠的。     

SDH网管软件开发中的设计模式

设计模式描述了在软件开发过程中经常出现的问题及其解决方案,是软件复用的有效途径。文章详细地分析了设计摸式中的Factory模式、Observer模式、Bridge模式在SDH网管软件开发中的应用,证明了在SDH网管系统中运用设计模式能够有效地提高系统质量、优化系统结构。     

设计模式在邮政代理保险系统中的研究与应用

介绍了适配器模式与桥模式的原理，并以邮政代理保险系统的软件设计为例，分析了它们在软件体系结构设计中的应用。     

A PSO algorithm for constrained redundancy allocation in multi-state systems with bridge topology

Bridge topology is a commonly used structure for load balancing and control in applications such as electric power generation and transmission, transportation and computer networks, and electronic circuits. The reliability performance of engineering systems with bridge topology can be characterized by multi-state models and enhanced by allocating redundant elements. The redundancy allocation problem, which aims at finding the optimal trade-off between system performance and investment costs, is proved difficult to solve and has received much attention in the literature. This paper advances a meta-heuristic approach called particle swarm optimization and applies it to effectively solve for near-optimal solutions to the redundancy allocation problem of multi-state systems with bridge topology. Two typical redundancy allocation problem formulations, i.e., minimizing the system cost while satisfying required system availability and maximizing the system availability with a limited budget, are studied. Heterogeneous redundancy, i.e., the mixture of redundant element types in each subsystem, is allowed in the formulations. The effectiveness and efficiency of the proposed approach are validated by the case studies of a bridge-structured coal conveyor multi-state system with extra constraints. The research results have practical meaning to the design and improvement of engineering systems with bridge topology.     

Detecting safety‐related components in statecharts through traceability and model slicing

With rapid development in software technology, more and more safety‐critical systems are software intensive. Safety issues become important when software is used to control such systems. However, there are 2 important problems in software safety analysis: (1) there is often a significant traceability gap between safety requirements and software design, resulting in safety analysis and software design are often conducted separately; and (2) the growing complexity of safety‐critical software makes it difficult to determine whether software design fulfills safety requirements. In this paper, we propose a technique to address the above 2 important problems on the model level. The technique is based on statecharts, which are used to model the behavior of software, and fault tree safety analysis. This technique contains the following 2 parts, which are corresponding to the 2 problems, respectively. The first part is to build a metamodel of traceability between fault trees and statecharts, which is to bridge their traceability gap. A collection of rules for the creation and maintenance of traceability links is provided. The second part is a model slicing technique to reduce the complexity of statecharts with respect to the traceability information. The slicing technique can deal with the characteristics of hierarchy, concurrency, and synchronization of statecharts. The reduced statecharts are much smaller than their original statecharts, which are helpful to successive safety analysis. Finally, we illustrate the effectiveness and the importance of the method by a case study of slats and flaps control units in flight control systems.     

核电站数字化保护系统设计研究

保护系统是核电站中保证核电安全的重要系统,采用数字化技术设计保护系统已成为当前的主流。核安全法规、标准对保护系统设计提出了单一故障、冗余性、独立性等设计准则。基于这些设计准则,应用当前成熟的DCS控制技术及点对点、环网等通信技术,设计了适用于M310堆型的保护系统的原型系统,该原型系统除应用数字化技术外,还设计了可以防止数字化系统软件共因故障影响的模拟控制装置,实现保护功能的多样性控制。通过分析表明该系统符合纵深防御和多样性要求,且满足单一故障准则。     

三余度飞控系统余度管理算法设计与实现

利用余度技术可以很好提高飞行控制计算机系统的可靠性和容错能力;余度设计的的故障容错能力主要是通过系统的余度管理来实现的;在对余度管理算法进行了深入研究的前提下,结合嵌入式实时操作系统VxWorks的特点,详细描述了三余度飞控计算机系统余度管理算法的设计流程,采用这样的设计使得系统结构紧凑,大大提高了系统的实时性和安全性要求.