Special army requirements for tactical data systems

World Abstracts on Microelectronics and Reliability

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shop was to identify problem areas and develop recomdata--the British Army's methods and experience. M~OR- mendations to improve electronic equipment reliability. GENERALV. METCALEE.Proc. A. Reliability and Maintaina- The meeting at Airlie House culminated nine months of bility Symposium, Nevada, U.S.A.p. 387 (20-22 Jan. 1976). effort directed toward the development of changes in poliThis paper describes the FORWARDmaintenance data sys- cies, procedures, and techniques which would result in the tem which has been developed and implemented by the acquisition and fielding of more reliable electronic systems. British Army during the past decade. Under this system The Workshop recommendations include immediately implementable actions such as: revising reliability test prorepair, inspection and modification activity carried out by the Royal Electrical and Mechanical Engineers is reported grams to yield "real world" results, the development of continuously to a Data Centre equipped with an ICL a real time field reliability reporting system to permit correction rather than, merely, the repair of design differences 1904S computer. The data is stored in a Repair Data Bank and the publishing of revised and new reliability guidance and used to monitor the behaviour of equipment in field service and assess its reliability and maintainability. The documentation to allow for proper and enforceable conpaper stresses two principal characteristics of the system tract provisions. In addition, a new Joint Technical Coorwhich are that it produces both equipment and managedinating Group on Electronic Systems Reliability has been ment information and that the basic system can be chartered by the Joint Logistics Commanders which will enhanced for selected equipment types (e.g. aircraft) or supbe responsible for the implementation of the Workshop plemented by collecting additional data over a limited recommendations. period for special studies in depth. The limitations of the FORWARDsystem as well as its capabilities are discussed • Estimating the reliability of complex systems. J. N. IRWIN. and an indication of possible future developments is given. Proc. A. Reliability and Maintainability Symposium, The paper indicates some of the problems which have been Nevada, U.S.A.p. 420 (20-22 Jan. 1976). This paper deencountered in managing the project and describes the scribes by the use of a simple hypothetical example the methods adopted to deal with them. principles of the technique used by Hunting Engineering Ltd. to predict the reliability of complex weapon systems. Spares and systems availability. WILLIAMJ. VANDENBOSCH. Proc. A. Reliability and Maintainability Symposium, Nuclear industry--approach to performance assurance. Nevada, U.S.A.p. 405 (20-22 Jan. 1976). An approach is ALAN E. SIEBE. Proc. A. Reliability and Maintainability developed to analyze the effects of different sparing levels Symposium. Nevada, U.S.A.p. 430 (20-22 Jan. 1976). Relion system availability. Important sparing parameters deable and incident-free performance are becoming increasrived are: the probability density function of the system's ingly more important in the nuclear power electric generavailability; the time between restocking the spare supply; ation industry. The quality philosophy that had evolved number of spares for a probability level that a spare will is primarily keyed to assuring the proper performance of be available; the expected system down time due to lack nuclear safety related equipment. Why were the efforts of a spare; the number of spares for the lowest cost; and focused in the safety related sphere? Has the implementhe average and minimum system availability. An example tation of this philosophy been effective? With the impact of the analysis of a system is shown to illustrate the of the energy crisis, attention is being focused on overall method. The approach presented is based on approximaplant availability. How is the industry adjusting to this tions using the Central Limit Theorem and its asymptotic new emphasis? What challenges in the area of nuclear properties. The authors feel that these approximations are power plants face the assurance technologies in the future? accurate enough when one considers that this method will be utilized in the early phases of the system's life and that Approximation method for estimating meaningful paronly limited data will be available. ameters for a soft-controlled electro-mechanical system. ROBERT H. KEEGAN and ROBERT C. HOWARD. Proc. A. Reliability analysis management. HAROLDASCHER.Proc. A. Reliability and Maintainability Symposium. Nevada, U.S.A. Reliability and Maintainability Symposium, Nevada, U.S.A. p. 434 (20-22 Jan. 1976). The mechanics of calculating p. 383 (20-22 Jan. 1976). An Electronic Systems reliability Availability (A), Mean-Time-Between-Failure (MTBF), and Workshop, sponsored by the Joint Logistics Commanders Mean-Time-to-Repair (MTR) of a homogeneous, complex (JLC), convened during May 1975. The purpose of the system and its subsystems are well documented in the Workshop was to pinpoint areas which are causing system literature. The mathematics of combining unlike failure reliability problems and to propose programs to reduce, distributions for nonhomogeneous system elements conor hopefully eliminate, these problems. The Workshop was sisting of software, mechanical components and electrical organized into seven work groups which cofisidered manacomponents to obtain a classical reliability analysis is not gement problems relating to system acquisition and opertractable. One alternative estimating parameters for the ation, reliability testing, documentation, design techniques, system is to assume that electrical, mechanical, and softsoftware reliability, design techniques, software reliability ware failures follow an exponential failure rate. This and reliability analysis. This paper will review the proassumption generally is acceptable if the majority of comgrams recommended by the analysis work group with parponents are electrical with insignificant number of ticular emphasis on techniques useful to management in mechanical and software factors. Another approach is to the process of contracting for, and ensuring the delivery assume a particular failure rate distribution and rationalize of, operationally reliable systems. how each factor can meaningfully fit the chosen distribution. These assumptions were not valid for the class of Management of electronic equipment reliability. BERNARD equipment exemplified by the Mead Dijit ultra-high speed printer. Some other approach is needed. This paper presREICH and STANLEY GRUBMAN. Proc. A. Reliability and ents an approximation method for estimating MTBF, Maintainability Symposium Nevada, U.S.A.p. 378 (20-22 MTR, and A parameters for a commercially produced, Jan. 1976). This paper summarizes a portion of the output software-controlled electro-mechanical Ink Jet Imaging of a Joint Logistic Commanders, JLC, Electronic Systems System. The system studied is presently in production at Reliability Workshop. The Workshop, which was held at Mead Digital Systems, Inc., Dayton, Ohio. the Airlie House, VA., 5-9 May 1975, assembled teams comprised of recognized experts from government, industry, and academia, who addressed current reliability Special army requirements for tactical data systems. JOHN problems in the broadest scope. The objective of the WorkDE S. COUTINHO. Proc. A. Reliability and Maintainability The assessment of reliability and maintainability from field

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World Abstracts on Microelectronics and Reliability

Symposium. Nevada, U.S.A.p. 440 (20-22 Jan. 1976). The Army is in the process of developing several large Tactical Data Systems which promise to greatly increase its battlefield effectiveness. Because of its severe operating environment, these systems must meet special operating and maintenance requirements. A new quality control specification and a software acquisition guide have been published to improve development procedures.

A new assurance technology for computer software. DONALD J. REIFER. Proc. A. Reliability and Maintainability Symposium, Nevada, U.S.A.p. 446 (20-22 Jan. 1976). The high cost (both direct and indirect) and poor reliability of computer software have become subjects of major concern to members of the military and business communities. They recognize that computer software has become big business. Annual expenditures for software have exceeded $10 billion, with these costs expected to increase in the future. Yet, the current literature is filled with horror stories attributing large cost overruns and system failures directly to the poor management policies and inadequate quality control procedures that are presently applied to software developments. Many software practitioners recognize these problems exist and are now attempting to do something about them. The first steps they are taking in their attack on the problem are aimed at introducing sound management and engineering practices to the art of computer programming. Some of the combatants are drawing from their product assurance experience to develop a new assurance experience to develop a new assurance technology for computer software. The objective of this paper is to explain what this new assurance technology is all about. We shall accomplish this goal by first examining in detail the techniques of verification, validation, and certification as they are applied to the test and evaluation of computer software. Next, material is offered to show how these techniques provide technical management with the information they need to determine whether the computer program products that evolve during the software development process are correst with respect to their specifications. Application of these techniques on a variety of past military projects is discussed to provide a historical context. Based on the information reviewed, an assessment of the state of the technology as it is practiced today is made. Finally, recommendations which attempt to give direction to future efforts in this area are offered. A data base management (DBMP) program for integrated logistics support (ILS). A. CHRISTENSEN and R. S. J. VOVTEK. Proc. A. Reliability and Maintainability Symposium, Nevada, U.S.A.p. 467 (20-22 Jan. 1976). The Integrated Logistics Support function and its interdependent disciplines such as life cycle costing, reliability and maintainability engineering, spares determination and sparing philosophies is discussed in this paper. This inter-relationship is pursued from a Data Base Management Program (DBMP) viewpoint. The (DBMP) can be applied directly to the optimum design and selection of a system of equipment for a sailing vessel, an aircraft, a computer complex or a large orbiting space station. Trade-off of thermal cycling vs life cycle costs. M. J. SI4UMAKERand J. C. DuBuISSON. Proc. A. Reliability and Maintainability Symposium, Nevada. U.S.A.p. 300 (20-22 Jan. 1976). This paper presents a practical example of how and why total life cycle costs are affected by environmental testing. The example illustrates graphically why it is good management to spend more money initially during the production phase to avoid a larger number of field failures and their associated repair costs that would have occurred months or years after hardware delivery to the government. We relate predicted (MIL-HDBK-217B) and field

reliability, the ratio of dormant to operating reliability, the costs of thermal cycling at the factory, and the effectiveness of thermal cycling in catching weak or marginal parts to arrive at an optimum number of thermal cycles during acceptance testing.

Effects on LCC of test equipment standardization. HARRY ROSENBERG and JAMES H. WITT. Proc. A. Reliability and Maintainability Symposium, Nevada. U.S.A.p. 287 (20, 22 Jan. 1976). This paper discusses the results of an investigation to determine the potential life cycle cost savings from standardizing Test, Measurement, and Diagnostic Equipment (TMDE) of the U.S. Army Communications Command (USACC). Life cycle costs of three standard equipment types that could replace 55 nonstandard types were estimated for several replacement scenarios, and it was demonstrated that significant cost savings could be realized through standardization of these candidate TMDE. Maintainability analysis versus maintenance analysis---interface and discrimination. W. R. DOWNS. Proc. A. Reliability and Maintainability Symposium, Nevada, U.S.A.p. 476 (20-22 Jan. 1976). There is continuing confusion regarding maintainability engineering and maintenance engineering analyses in the ranks of contractors and in government agencies. The confusion occurs in delineating the differences between the two. Two basic, but totally different, responsibilities provide the main clues to the difference. Maintainability engineering is directed at assuring a design performance capability which will permit attaining a required operational capability; maintenance engineering is directed at assuring a proper integration of the system into the use environment in a manner which assures achieving the predicted system utilization. Both must be concerned with minimizing required resources/costs. This paper is based on a forthcoming Electronic Industries Association (EIA) Maintainability Bulletin entitled "Maintainability Analysis and Maintenance Analysis". The bulletin identifies (1) the differences that must be recognized in order to achieve the objectives of the maintainability engineering program, and (2) the interchange of data between the two analyses, which is conducive to reduced program costs. This paper is not concerned with assigning the various functions to organization slots; this is a company prerogative. It concentrates on identifying the major elements of maintainability analysis and some of the more important interfacing maintenance analysis functions, outlining why elements are assigned to a specific discipline. Although the two fields are closely related, it is important to be able to distinguish between them so as to assure that each is planned and carried out efficiently by programs with a proper purpose and personnel with the proper skills. Realization of maintainability as a design attribute and as an asset for achieving high product utilization requires (1) substantive requirements and guidelines from the procuring agencies, (2) meaningful planning and manning by contractors, and (3) timely implementation of support capability in the field (to accommodate the selected cost effective measures that may depart from past practices). Proper accomplishment will assure maintainability in the design, a minimum of surprises in regard to achieving operational availability, and that the required resources are delivered with the product. IEEE Project 500~reliability data manual for nuclear power generating stations A. J. MCELRO¥. Proe. A. Reliability and Maintainability Symposium. Nevada, U.S.A.p. 277 (20-22 Jan. 1976). IEEE Project 500~formed in the Nuclear Power Engineering Committee of the Power Engineering Society---is expected to serve as a source for nuclear plant failure rate data. The manual will cover all electrical, electronic, and sensing components in nuclear power