面向航空航天领域的工业CFD软件研发设计

工业CFD (computational fluid dynamics)软件属于计算机辅助工程(computer-aided engineering, CAE)软件的一种, 在航空航天等领域有着广泛的应用. 其开发过程强烈依赖于流体力学、数学、计算机以及其他领域学科知识模型, 涉及大量理论推导、模型构建、算法优化、验证...     

软件验证与确认在MIS开发中的应用

介绍软件验证和软件确认的概念及其相互关系,以一个实际的管理信息系统开发项目为例,描述在软件开发生命周期中验证和确认活动的具体实现,以及如何使验证和确认与项目的整个生命周期相配合、如何与项目实体相关联,证明软件验证和确认是保证软件产品质量的有效手段.     

面向机载软件的预期功能安全分析验证过程及方法研究

预期功能安全（Safety of the Intended Functionality,SOTIF）关注系统与外界环境、交联设备、任务场景和操作人员交互时,由自身功能设计不足而导致的安全隐患,非常适用于具有复杂功能逻辑的系统和软件研制过程。但目前尚未见到SOTIF在机载软件安全性分析验证工作中的研究与应用,导致机载软件安全性分析验证过程难以适用于复杂失效的分析识别。因此借鉴SOTIF在汽车领域的成功应用经验,开展面向机载软件的SOTIF分析验证过程与方法研究。首先,参考ISO 21448标准,提出机载软件SOTIF分析验证框架。然后,借助功能危险分析、故障树模型、场景驱动等理论,针对过程中涉及的SOTIF分析验证技术进行研究,识别机载系统危险,分析软件异常控制行为及其原因,构建SOTIF测试场景与测试用例,形成基于SOTIF的机载软件安全性分析验证完整闭环。最后,通过SOTIF技术在机轮转弯控制软件的典型工程应用,验证了该研究成果的有效性和可行性,形成了面向机载软件的SOTIF分析验证过程与能力,可支撑研制人员充分识别机载软件运行过程中软硬耦合冲突、人机交互异常、场景切换异常等复杂失效模式,确保机载软件满足高安全、高可靠研制要求。     

试论软件测试学科的架构建设

给出了软件测试学科的一个新的理论框架模型,在此框架模型中,软件测试学科由软件验证技术、软件确认技术以及软件测试管理技术这三个部分组成.然后逐一描述了这三个部分的具体内容以及它们在软件生命周期中的相互关系,从而阐述了对软件测试学科架构建设的新见解.     

ARINC429总线通讯软件测试环境的构建

ARINC429总线是航空电子设备的数字总线传输标准,目前广泛应用于各种航空电子设备中,其有效、便捷、可靠的数据传输是保证设备之间资源共享和信息传输的重要前提;这里采用基于功能的测试方法和测试技术,探讨ARINC429通讯软件等效测试环境的构建,并提出被测软件确认测试环境的一种具体构建方法;该测试环境模拟被测目标软件实际运行环境,在无需系统其它硬件支持的情况下,完成ARINC429总线通讯确认测试,确保了数据在ARINC429总线上可靠的传输。     

面向对象设计中软件度量学:回顾与热点

为了深入、详细、全面地研究面向对象软件度量,以1968年Rubey等人提出软件度量学的概念为起点,横跨四十余年,从度量方法的定义、理论验证、实验验证和辅助工具四个方面进行了阐述,并从软件内部属性、软件外部属性、数据源性质、数据源的开发语言、实验方法和实验结论等方面总结了典型的实验验证.最后,指出了其存在的问题,并指明了...     

A comparison of standards for software engineering based on DO-178B for certification of avionics systems

Certification of avionics software is an increasingly important subject, since more and more avionics systems in future aircraft will be software equipped. The DO-17813 standard provides guidelines for software certification. Re-use of software is emerging, partly enabled by the integrated modular avionics concept, and imposed by a reduction of life-cycle costs. Re-use, however, requires re-certification or certification of software that was not developed according to DO-17813.

The DO-178B standard is specially developed to provide a certification basis for avionics software, without going into details of the software development process. Other standards focus on software engineering aspects. We have used the DO-178B standard as a common basis for comparison with DOD-STD2167A (military), ESA PSS-05-0 (space), and IEC65A(Secretariat)122 (industry). Comparison topics include:

• • life cycles;

• • prescribed documentation;

• • configuration management;

• • verification and validation;

• • quality assurance.

All standards prescribe the software development process, emphasizing specific aspects in a certain area of interest. The results of our investigation will assist in understanding the rationale behind several standards, and can be used for:

• • certification according to DO-17813 of software that was developed using another standard;

• • certification of software using DO-17813, in concert with another standard.

     

Integral: Petri-net approach to distributed software development

As the architecture of modern software systems continues to evolve in a distributed fashion, the development of such systems becomes increasingly complex, which requires the integration of more sophisticated specification techniques, tools, and procedures into the conventional methodology. An essential capability of an integrated software development environment is a formal specification method to capture effectively the system's functional requirements as well as its performance requirements. A validation and verification (V&V) system based on a formal specification method is of paramount importance to the development and maintenance of distributed systems.

There has been recent interest in integrating software techniques and tools at the specification level. It is also noted that an effective way of achieving such integration is by using wide-spectrum specification techniques. In view of these points, an integrated V&V system, called Integral, is presented that provides comprehensive and homogeneous analysis capabilities to both specification and testing phases of the life-cycle of distributed software systems. The underlying software model that supports various V&V activities in Integral is primarily based on Petri nets and is intended to be wide spectrum. The ultimate goal of this research is to demonstrate to the software industry, domestic or foreign, the availability and applicability of a new Petri-net-based software development paradigm. Integral is a prototype V&V system to support such a paradigm.     

软件确认测试概述

软件确认测试在软件测试生命周期中占有重要地位。尽管在整个开发过程中经历了各种测试和检验,但是,在其正式发布和投入运行之前仍必需通过正式的和系统全面的测试,来确认其是否符合需求。本文介绍了软件确认测试的主要测试内容及活动,分析了确认测试在软件开发过程中的作用和地位,归纳了确认测试的基本测试模型,总结了确认测试的基本测试过程和方法。     

A rule‐based approach to detect and prevent inconsistency in the domain‐engineering process

A medium‐sized domain‐engineering process can contain thousands of features that all have constraint dependency rules between them. Therefore, the validation of the content of domain‐engineering process is vital to produce high‐quality software products. However, it is not feasible to do this manually. This paper aims to improve the quality of the software products generated by the domain‐engineering process by ensuring the validity of the results of that process. We propose rules for two operations: inconsistency detection and inconsistency prevention. We introduce first‐order logic (FOL) rules to detect three types of inconsistency and prevent the direct inconsistency in the domain‐engineering process. Developing FOL rules to detect and prevent inconsistency in the domain‐engineering process directly without the need to the configuration process is our main contribution. We performed some experiments to test the scalability and applicability of our approach on domain‐engineered software product lines containing 1000 assets to 20000 assets. The results show that our approach is scalable and could be utilized to improve the domain‐engineering process.     

核安全关键软件的验证与确认技术

介绍了加拿大重水铀反应堆CANDU的安全关键软件的验证与确认(V&V)技术,说明了CANDU核反应堆停堆系统的脱扣计算机及其设计方法,详细描述了用于停堆脱扣计算机软件的确认和可靠性V&R测试的多功能测试平台,以及该测试平台在停堆脱扣计算机软件V&R测试中的应用.V&V技术已被成功地应用于各国CANDU核反应堆停堆系统的脱扣计算机设计中,如韩国的月城CANDU核反应堆、中国的秦山CANDU核反应堆、罗马尼亚Cernavda的2号CANDU核反应堆和加拿大Point Lepreau重建的CANDU核反应堆.随着计算机软硬件技术的发展,所描述的过程和工具在近期的项目中已得到了不断的改善.     

Philosophy of science underpinnings of prototype validation: Popper vs. Quine

Abstract.  In this paper, we aim to provide prototype validation in both custom and packaged software development with a theoretical framework located within the philosophy of science. Towards that end, we consider Popperian and Quinean accounts of scientific knowledge and argue that the theoretical underpinning of prototype validation is Quine's holistic philosophy of science, whose cornerstone principle is that all beliefs are revisable. Specifically, our thesis is that the systems developer and software consumer (user or customer) join forces – not as Popperian falsifiers, who make a decision rule to reject the prototype on account of any divergence, major or minor, from the software consumer's mental model, but – as Quinean revisers, with the objective of fine-tuning the prototype (or the software consumer's mental model) so that the prototype and the software consumer's mental model are congruent with each other. This paper suggests that prototype revisions are belief revisions, and, as such, should be guided – and are guided – by pragmatic norms, such as conservatism, simplicity and generality, and are influenced by social, or sociological, factors as well. Finally, we discuss the relevance, value and pragmatic implications of a Quinean philosophy of science framework for research and practice.     

核电厂DCS安全级应用软件开发的危险分析

为了减小或避免因控制系统软件而导致的核电厂安全性降低的不良后果,提出了对核电厂数字控制系统安全级应用软件开发过程进行危险分析的活动.采用验证和确认的方法,并结合安全保护层模型、预先危险分析方法(PHA)、故障树分析等方法对应用软件开发过程中的系统设计、软件设计、软件实现各个阶段的危险进行分析.通过CPR1000项目工程实践表明,采用验证和确认的方法能有效地减小软件开发过程中的危险以提高应用软件的安全性,从而最终提高核电厂的安全性.     

基于黑盒测试的航天嵌入式软件用例设计方法

为了提高测试用例设计的效率,简化测试用例数量,提出了基于黑盒测试的航天嵌入式软件用例设计方法.阐述了确认测试过程中实用的测试用例设计流程,提出了在设计测试输入数据的基础上加强测试逻辑设计的用例设计方法,并结合实际工程经验,给出了测试用例的总体设计思路.最后,对测试遗漏问题及其原因进行了分析,为今后进行更有效的星载软件测试提供了参考.     

复杂软件需求开发方法研究

软件需求开发方法研究是当前复杂软件系统开发中最重要的问题之一。本文首先基于软件开发生命周期模型,对软件需求开发工作进行了介绍。进而总结了软件需求所必须包含的内容,分析了软件需求的特性。基于迭代改进的开发方法,本文将需求开发工作分解为需求捕获、需求分析、需求编写和需求确认四部分活动,并对每部分工作的详细活动和目的进行了分析和总结。软件开发工程实践证明,科学的软件需求开发方法是提高软件开发效率,提高软件开发质量的重要手段。     

轨道交通控制软件中基于场景的需求分析方法

针对轨道交通控制软件的形式化方法,在实际工程应用中存在形式化建模和系统级场景验证困难的问题。提出一种面向轨道交通领域的形式化建模和需求确认及验证方法。通过非形式化、半形式化到形式化规约三步演化过程,为形式化规约构建提供模板。在对需求的确认和验证中,根据形式化规范建立需求模型,导出相关图表,基于此检查领域专家关注的场景。同时制定场景描述规则,使场景可以在需求模型中正确执行。在此基础上,从特殊变量、效率、场景质量三方面对场景进行优化,更充分地验证需求的正确性。实验结果表明,对于典型车载控制软件,该方法较传统分析方法可多探测到10%的潜在缺陷,效率提升80%以上。     

浙江省计算机二级办公软件高级应用技术上机考试技巧解析

该文从考试时间安排、解题技巧两方面,介绍了在浙江省计算机二级办公软件高级应用技术考试中考生的常见问题及解决方法。     

一种办公软件集成模型的应用研究

随着社会信息化程度提高和软件技术的发展,形成了一个组织内部同使用多种软件系统情况。由于多个软件系统各自独立,数据无法共享造成了工作效率低下,重复劳动,软件系统的维护和扩展受限等问题。针对这些问题软件集成成为软件工程研究热点之一,该文则是针对办公软件的特点提出一种新的办公软件集成模型,该模型基于数据流重组,数据流与工作流的高耦合形成业务流,实现可靠的办公软件系统集成。经分析表明,本模型具有较高的可靠性,扩展性和可维护性,因而具有较好的实际使用价值。     

航空机载嵌入式控制软件需求建模的形式化工程方法

嵌入式控制软件是现代航空飞行器的核心部件之一。构建软件需求的形式化规约精确地刻画人们对软件期望的功能和运行场景,是确保此类安全攸关软件质量的根本途径。在工业界,形式化需求建模的大规模应用尽管有成功的案例,但仍面临众多的困难。其根本性难点在于缺少一种系统化的工程方法来引导工业界软件实践者,从原始需求开始最终完成形式化需求规约,并能确认该规约真实、充分地反映了人们对软件期望的功能。针对上述挑战,提出了一种面向机载控制软件需求建模的形式化工程方法ACSDL-MV,以形式化方法为理论基础,结合软件需求工程的基本原理,引导工程人员从原始需求出发以演化式的过程逐步完成需求规约的构建;定制了航空控制软件的形式化描述语言ACSDL,用以构建形式化规约;为了确认软件需求规约准确、充分地描述了人们对软件期望的功能,该方法给出了基于图形的静态审查和基于模型的动态模拟技术。在航空发动机公司中的实验结果表明,该方法相比传统方法探测到了更多的潜在错误。