DEPENDABILITY, №4(51)-2014

Structural reliability. The theory and practice

• Netes V.A., Tarasyev J.I., Shper V.L.
  HOW WE SHOULD DEFINE WHAT “DEPENDABILITY” IS

Currently, the Technical committee for standardization “Dependability in equipment” (TC 119) is developing a new interstate standard “Dependability in equipment. Terms and definitions” that will replace GOST 27.002–89. The issue was already discussed at the pages of our journal. In Issue 2 this year there was a report about the meeting of a permanent scientific seminar “Dependability and quality of system functioning” that took place on the 30th of January 2014 and was devoted to discussion of key issues related to the development of this standard. In the same issue there was a paper by active participants of the work V.A. Netes, J.I. Tarasyev, V.L. Shper Current issues of terminology standardization in dependability where the authors started a detailed consideration of this important topic.
Keywords: dependability in equipment, terminology standardization.

• Viktorova V.S., Stepanyants A.S.
  DEPENDABILITY INDICES OF MEAN TIME TYPE

The paper discusses mathematical definitions of such dependability indices as mean time to failure, mean time between failures and mean time before failure introduced in basic standards and theoretical literature related to dependability. The paper also describes methods for practical calculation of indices for design analysis of system dependability. It is demonstrated that the definition and use of such parameter as mean time before failure are incorrect.
Keywords: dependability, mean time to failure, mean time between failures, mean time before failure, Markov models.

• Maystrenko I.Y., Zinnurov T.A., Yusupov I.I.
  ANALYSIS OF DESIGN DEPENDABILITY OF CRITICAL UNITS OF ARCH SPANS OF PEDESTRIAN OVERPASSES BASED ON NUMERICAL AND SIMULATION METHODS

The paper deals with the design dependability of the grip-arm interface “arch – bowstring – jack beam” in spans of pedestrian overpasses. Dependability estimation required the performance of a number of simulation procedures that include five basic steps. Exhaustion of weight strength in one of the critical element of the arch – bowstring – jack beam joint was the criterion of making a decision about failure.
Keywords: design dependability, simulation, pedestrian overpass, load, confidence interval.

• Nosov М.В.
  METHOD FOR ELIMINATION OF MUTUAL CROSSING OF ESARY-PROSCHAN ESTIMATES IN TASKS OF ANALYSIS OF BIPOLAR NETWORKS CONNECTIVITY

The paper presents the method for elimination of mutual crossing and reduction of Esary-Proshan estimates errors.
Keywords: sprobability of connection, probability of discontinuity, bipolar network, random graph of bipolar network, simple path, simple cut, upper bound, lower bound, exact value, Esary-Proshan estimates, bilateral estimates, elementary designs.

• Pegushin S.L., Shumikhin A.G.
  APPLICATION OF THE TACTICS OF DEPENDABILITY CONSECUTIVE CHECK TESTS OF CAM ELEMENTS AND AUTOMATED SIS UNDER OPERATING CONDITIONS FOR USE OF RESULTS IN FMEA ANALYSIS

The paper considers the technique based on the tactics of consecutive check tests of dependability and applied for the equipment of computer-aided manufacturing (CAM) and automated safety instrumented systems (SIS) of oil refineries under operating conditions, with subsequent use of testing results in failure mode and effects analysis (FMEA). It is supposed that operation conditions for various types of equipment correspond to a mode of system “regular” functioning and to the exponential law of distribution of mean time to failure. The IDEF3 notation of structural modeling describes the testing process, analysis of failure causes, and development of measures to prevent them. A common database on dependability check tests is kept in PDM (Product Data Management) system.
Keywords: oil refining, automated control system, dependability, failure causes and effects, analysis.

Functional reliability. The theory and practice

• Shubinsky I.B.
  OVERVIEW OF DECISION-MAKING TECHNIQUES USED IN THE DEVELOPMENT OF COMPLEX ENGINEERING SYSTEMS

With the advent of market economy in Russia the role of the decision-making stage in the devel-opment of high-technology products significantly rose in significance. The article analyzes the mathematical model of decision-making used in the development of complex engineering systems (CES) that allows identifying the optimal engineering solutions out of a number of alternatives. In order to define the "efficiency" of CES and primary criteria thereof the authors set forth a number of classifications of decision-making techniques along with their main features. They also provide the results of comparative analysis of the best known decision-making techniques, as well those used for evaluation of innovation projects.
Keywords: system analysis, complex engineering system, decision-making procedure, decision-making techniques, decision-maker, alternative, efficiency, efficiency criteria, comparative analysis.

• Shubinsky I.B., Schäbe H.
  METHODS OF SOFTWARE FUNCTIONAL DEPENDABILITY ASSURANCE

The paper considers the basic aspects of the construction of reliable software. It discusses methods and ways of error prevention based on protective and multiversion programming, tools of passive and active detection of errors, principles and methods of error correction based on dynamic redundancy and restart. Some emphasis is made on solving the tasks of construction of error-tolerant programs with the help of digression methods, techniques of error isolation and construction of redundant algorithms not critical to various types of information process violations.
Keywords: a program, an error, software dependability, error prevention, error detection, error correction, error-tolerant software, antibugging, multiversion programming, restart, dynamic redundancy, algorithmic redundancy, isolation of errors.

• Terskov V.A., Sheenok D.A., Kartsan I.N.
  GENETIC ALGORITHM FOR OPTIMIZATION OF ONBOARD SOFTWARE ARCHITECTURE

The paper describes the model of onboard software architecture that allows us to assess the dependability of a designed program system and labour efforts spent on its realization. The paper defines parameters and operators of the genetic algorithm that makes it possible to find optimal characteristics of onboard software architecture.
Keywords: genetic algorithm, onboard software, program redundancy, software dependability.

Functional safety. The theory and practice

• Semenov S.S., Poltavsky A.V., Maklakov V.V.
  PROCESS OF DECISION-MAKING IN DEVELOPMENT OF COMPLEX TECHNICAL SYSTEMS AND THE TASK OF CHOICE OF ALTERNATIVES

Developing highly competitive products involves making well-grounded and correct decisions which can be ensured by a systemic approach to the creation of new products and advanced decision-making methods. One of the primary concepts of system analysis is the concept of decision-making. The paper considers the primary lifecycle stages of a complex engineering system (CES), the statement of the decision-making problem in respect to CES development and conditions of selection of solution methods as part of alternative solutions analysis. The authors demonstrate the significance of the decision-making process at various stages. From the standpoint of state-of-the-art concepts, the paper provides a detailed description of the decision-making procedure proper that involves seven stages – from the purpose of problem solution to its implementation.
Keywords: complex engineering system, multilevel complex engineering systems, system analysis, lifecycle, lifecycle stage, decision-making process, decision-maker, alternative, efficiency indicators and criteria.

Information

• Information about InnoTrans
• Book by Shubinsky I.B. «Structural Reliability of Information Systems»
• Book by Shubinsky I.B. «Functional Reliability of Information Systems»
  
• Training courses in reliability - Gnedenko Forum