Методика определения показателей надежности отказоустойчивых программно-аппаратных радиоэлектронных систем

У роботі представлена методика визначення надійності програмних засобів на етапі експлуатації, розроблена методика визначення надійності програмно-апаратних радіоелектронних систем у відповідності до вимог програмного та апаратного забезпечення.Introduction. The majority of radioelectronic systems are hardware-software systems. Their reliability is defined as the reliability of hardware and software. Methods for estimating software allow to predict reliability based on experiments and tests during the testing verification and validation time, but there is no specific models for assessing the reliability during operation time. Problem statement. In many approaches, when assessing the reliability of hardware-software systems consider that software reliability is equal to 1, and consider only reliability of hardware. In other approaches consider that the reliability of PAS depends on the software and hardware reliability. Hardware and software features differ significantly. Important is to create methodology for determining the reliability of hardware-software systems considering hardware and software adequate models. Developing software reliability models. Was carried out the analysis of software reliability models according to its life cycle. Software reliability model in operation time is proposed as a set of Heaviside functions. Developing hardware reliability models. Was carried out the analysis of hardware reliability according to the technology [3]. Developing software-hardware reliability models. Was carried out the analysis of software-hardware systems considering the reliability of hardware and software during operation time.В работе представлена методика определения надежности программных средств на этапе эксплуатации, разработана методика определения надежности программно-аппаратных радиоэлектронных систем в соответствии с требованиями программного и аппаратного обеспечения

Методика визначення показників надійності відмовостійких програмно-апаратних радіоелектронних систем

Introduction. The majority of radioelectronic systems are hardware-software systems. Their reliability is defined as the reliability of hardware and software. Methods for estimating software allow to predict reliability based on experiments and tests during the testing verification and validation time, but there is no specific models for assessing the reliability during operation time. Problem statement. In many approaches, when assessing the reliability of hardware-software systems consider that software reliability is equal to 1, and consider only reliability of hardware. In other approaches consider that the reliability of PAS depends on the software and hardware reliability. Hardware and software features differ significantly. Important is to create methodology for determining the reliability of hardware-software systems considering hardware and software adequate models. Developing software reliability models. Was carried out the analysis of software reliability models according to its life cycle. Software reliability model in operation time is proposed as a set of Heaviside  functions. Developing hardware reliability models. Was carried out the analysis of hardware reliability according to the technology [3]. Developing software-hardware reliability models. Was carried out the analysis of software-hardware systems considering the reliability of hardware and software during operation time.В работе представлена методика определения надежности программных средств на этапе эксплуатации, разработана методика определения надежности программно-аппаратных радиоэлектронных систем в соответствии с требованиями программного и аппаратного обеспечения.У роботі представлена методика визначення надійності програмних засобів на етапі експлуатації, розроблена методика визначення надійності програмно-апаратних радіоелектронних систем у відповідності до вимого програмного та апаратного забезпечення.Ключові слова: надійність, програмне забезпечення, апаратне забезпечення, про-грамно-апаратні систем

Validation of highly reliable, real-time knowledge-based systems

Knowledge-based systems have the potential to greatly increase the capabilities of future aircraft and spacecraft and to significantly reduce support manpower needed for the space station and other space missions. However, a credible validation methodology must be developed before knowledge-based systems can be used for life- or mission-critical applications. Experience with conventional software has shown that the use of good software engineering techniques and static analysis tools can greatly reduce the time needed for testing and simulation of a system. Since exhaustive testing is infeasible, reliability must be built into the software during the design and implementation phases. Unfortunately, many of the software engineering techniques and tools used for conventional software are of little use in the development of knowledge-based systems. Therefore, research at Langley is focused on developing a set of guidelines, methods, and prototype validation tools for building highly reliable, knowledge-based systems. The use of a comprehensive methodology for building highly reliable, knowledge-based systems should significantly decrease the time needed for testing and simulation. A proven record of delivering reliable systems at the beginning of the highly visible testing and simulation phases is crucial to the acceptance of knowledge-based systems in critical applications

A practical experience with independent verification and validation

One approach to reducing software cost and increasing reliability is the use of an independent verification and validation (IV & V) methodology. The Software Engineering Laboratory (SEL) applied the IV & V methodology to two medium-size flight dynamics software development projects. Then, to measure the effectiveness of the IV & V approach, the SEL compared these two projects with two similar past projects, using measures like productivity, reliability, and maintain ablilty. Results indicated that the use of the IV & V methodology did not help the overall process nor improve the product in these cases

Annotated bibliography of software engineering laboratory literature

An annotated bibliography is presented of technical papers, documents, and memorandums produced by or related to the Software Engineering Laboratory. The bibliography was updated and reorganized substantially since the original version (SEL-82-006, November 1982). All materials were grouped into eight general subject areas for easy reference: (1) The Software Engineering Laboratory; (2) The Software Engineering Laboratory: Software Development Documents; (3) Software Tools; (4) Software Models; (5) Software Measurement; (6) Technology Evaluations; (7) Ada Technology; and (8) Data Collection. Subject and author indexes further classify these documents by specific topic and individual author

Testing in the incremental design and development of complex products

Testing is an important aspect of design and development which consumes significant time and resource in many companies. However, it has received less research attention than many other activities in product development, and especially, very few publications report empirical studies of engineering testing. Such studies are needed to establish the importance of testing and inform the development of pragmatic support methods. This paper combines insights from literature study with findings from three empirical studies of testing. The case studies concern incrementally developed complex products in the automotive domain. A description of testing practice as observed in these studies is provided, confirming that testing activities are used for multiple purposes depending on the context, and are intertwined with design from start to finish of the development process, not done after it as many models depict. Descriptive process models are developed to indicate some of the key insights, and opportunities for further research are suggested

How reliable are systematic reviews in empirical software engineering?

BACKGROUND – the systematic review is becoming a more commonly employed research instrument in empirical software engineering. Before undue reliance is placed on the outcomes of such reviews it would seem useful to consider the robustness of the approach in this particular research context. OBJECTIVE – the aim of this study is to assess the reliability of systematic reviews as a research instrument. In particular we wish to investigate the consistency of process and the stability of outcomes. METHOD – we compare the results of two independent reviews under taken with a common research question. RESULTS – the two reviews find similar answers to the research question, although the means of arriving at those answers vary. CONCLUSIONS – in addressing a well-bounded research question, groups of researchers with similar domain experience can arrive at the same review outcomes, even though they may do so in different ways. This provides evidence that, in this context at least, the systematic review is a robust research method

Production of Reliable Flight Crucial Software: Validation Methods Research for Fault Tolerant Avionics and Control Systems Sub-Working Group Meeting

The state of the art in the production of crucial software for flight control applications was addressed. The association between reliability metrics and software is considered. Thirteen software development projects are discussed. A short term need for research in the areas of tool development and software fault tolerance was indicated. For the long term, research in format verification or proof methods was recommended. Formal specification and software reliability modeling, were recommended as topics for both short and long term research