RPM—A recent real life case history

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World Abstracts on Microelectronics and Reliability

Reliability, Availability and Maintainability (RAM) Engineering techniques were always in use in the Electric Power Industry, though they were not as formalized as they have been in the last few years. The increasing cost of oil and gas along with the increasing cost involved in burning coal has fostered the requirement to use only electric power equipment with the lowest life cycle cost, In order to meet this objective formalized Reliability, .Availability and maintainability methods and procedures were used. This paper presents the RAM techniques adapted from the aerospace program as they are presently used in the Electric Power Industry. In addition a new approach to the establishment and maintenance of equipment failure rate data bases tusing optical scanning techniques) will also be presented. The significance of using RAM engineering methodology on Electric Power equipment will be presented with several applications. Two (2) of these applications in particular were the first in the Electric Power Industry to be procured with specifications containing quantitative Reliability and Maintainability requirements. Since Con Edison is involved in Nuclear and Fossil Power Generation. Transmission and Distribution, the applications in this paper cover the entire system of an Electric Utility's operation. An analytical approach to determining optimum reliability and maintainability requirements. ARMAND A. LAKNER and RONALD T. ANDERSON. Radio Electron. Enyr 48, (7;8) 355 (July/August 1978). In order to assure that the United States Federal Aviation Administration tFAA) National Airspace System (NAS) equipments are reliable, maintainable and cost effective, a comprehensive methodology for achieving optimum Reliability and Maintainability (R&M) levels has been developed by the Airway Facilities Service in the FAA. This paper describes the methodology, its approach and the. specific life cycle cost (LCC) models used in the computation of optimal levels of R&M. It provides criteria, guidelines. rationale, and formulae which the FAA is applying to its procurements in order to determine optimum mean-timebetween failure (m.t.b.f., 0) and mean-time-to-repair (m.t.t.r., r) design values for use in its hardware specification. The methodology is based upon LCC principles which are fully in accord with FAA needs. Value engineering and the problems of time and deadlines. R. REINHEIMER.Feinwk-Tech. Messtechnik 86, (5) 237 (1978). (In German.) This paper shows the difficulties, in part deliberately fabricated, that a value engineer must face when carrying out his work. For overcoming these obstacles, the biggest and most important of which is the acute problem of time and deadlines, the value engineer has a number of possibilities at hand of which a few are given here. Work skilfully arranged under psychological aspects, consideration of the mentality of the employees, thorough training and good motivation of the staff are as decisive a factor as the use of all modern aids and equipment available. Burn-in foreveH There must be a better way! J. DOUGLAS EKINGS and ROBERT L. SWEETLAND. Proc. IEEE A. Reliab. Maintainab. Symp., Los Angeles, 17-I9 January 1978, p. 286. In the electronics industry, burn-in is a classical method for eliminating infant mortality failures and detecting problem trends. Burn-in usually proves a cost-effective reliability improvement technique for electronic products. In contrast, burn-in on a continuous production basis is seldom cost justifiable for complex business machines. However, machine burn-in or run-in under simulated field conditions is used for limited production periods on new copier programs. In typical new business machine production programs, schedules leave little time for traditional reliability test techniques. Business machine reliability performance and failure information may be inadequate. In these situations, the combined advantages of reliability

screening and problem identification from bum-in can prove valuable. To insure that all possible reliability information is obtained from burn-in, an applied decision theory was developed. The method has been applied as a Xerox standard to several copier programs and is described in this paper. The technique enables prediction of field performance through the use of known relationships that exist between machine reliability performance during burn-in and the field. A major benefit of the process is the creation of data for corrective action to enhance customer satisfaction during initial placement of new copiers. The technique also permits the logical termination of machine burn-in at a point where successful field performance is forecast, or the planning of additional burn-in capacity to achieve acceptable field results. This decision technique permits limiting burn-in and thus cost, while still guaranteeing acceptable field performance: as a result customer satisfaction and maximum corporate profits are assured. Progress in Liquid-Metal Fast Breeder Reactor safety research and development--An overview of the issues. M. H. FONTANA. Pro q. Nucl. Eneryy 2, 199 (1978). The safety of Liquid-Metal Fast Breeder Reactors has been the subject of massive world-wide research and development. This paper attempts to give a brief overview of the R & D directed toward an understanding of those events that could contribute to the release and transport of fission products and transuranic elements up to the boundary of the reactor secondary containment system. Motivating management on Maintainability. KRtS L. HELLAND. JR. Proc. IEEE A. Reliab. Maintainab. Syrup., Los Angeles, 17-19 January 1978, p. 32. This paper outlines the importance of Maintainability in a profit oriented business, with emphasis on the total life-cycle cost of a product that is to be either rented to a customer by the manufacturer, or sold to a customer along with a fixed price all inclusive service contract. For our purposes, Maintainability is defined as a discipline concerned with the optimization of the ability to maintain, which can be measured in dollars. Improved Maintainability is measured in increased profits. The company that rents equipment or sells maintenance contracts on equipment cannot afford to underestimate the importance of reducing the cost to maintain. Many companies have been very concerned with reducing the cost to make a product..For some, Maintainability is more than the other half of the story. It is similar to the underwater part of an iceberg. Manufacturing is a onetime cost, while maintenance goes on month after month--year after year. The cost of poor Maintainability is high, high in the cost of maintenance time and in customer dissatisfaction. Testing whether more failures occur later. M YLESHOLLANDER. Proc. IEEE .4. Reliab. Maintainab. Syrup., Los Angeles, 17-19 January 1978, p. 103. This is an expository paper which illustrates the role of superadditivity, in reliability theory, as a means of describing wearout. Statistical inference procedures are described for testing that minus the logarithm of a life distribution is superadditive, and for testing that the mean value function of a nonhomogenous Poisson process is superadditive. These tests are appropriate when the underlying processes suggest that new items are better than used ones but where we do not insist that the failure rate is increasing. R P M - - A recent real life case history. JAMES M. CLARKE and WILLIAM P. COUGAN. Proc. IEEE A. Reliab. Maintainab. Syrup., Los Angeles, 17-19 January 1978, p. 279. This paper presents a result-oriented case history of a reliability growth and demonstration test program conducted for a complex airborne surveillance radar processing system under Corn-

World Abstracts on Microelectronics and Reliability bined Environmental Reliability Test (CERT) conditions. The reliability growth or Test-Analyze-And-Fix (TAAF) test plan was dimensioned in accordance with the methodologies presented in "Reliability Planning and Management (RPM)'" (Ref. 1) and by Duane (Ref. 2). The paper describes in detail the significant elements of the test program including TAAF planning methods, the actual time-related pattern of growth test failure precipitation and the effects of changing CERT conditions, the method of implementing an effective closed-loop corrective action system, approaches taken to determine the achieved reliability growth level, and finally, the reliability demonstration test results.

Modeling with interactive computer methods. A. H. HEVESH and J. W. SULLIVAN. Proc. IEEE A. Reliab. Maintainab. Syrup.. Los Angeles, 17-19 January 1978. p. 324. An interactive computer program developed at Raytheon allows complex reliability models to be described and solutions to system reliability problems to be quickly obtained. The versatility of the program lies in its ability to treat systems containing hardware groups in active and inactive standby conditions simultaneously as well as systems with non-zero standby failure rates, Input data consists of any number of equipment groups in the system, each group being defined in terms of: --total quantity of elements used and numbers of active or dormant standby elements within each group --number of elements within each group permitted to fail without failing the system --element active failure rates and standby dormancy factors --computational method appropriate for exact reliability solution over the time intervals of interest. Variations of input data, as for alternate design candidates, may be easily exercised, enabling the computer to aid the user in optimizing the choice of how mui:h ~nd what kind of equipment is needed for least cost system solutions. Examples of some of the program's computational algorithms are described and some actual computer runs using the program are shown. Cost-effective reliability testing. A. A. LAKNER, R. T. ANDERSON and A. DIGIANntappo. Proc. IEEE A. Reliab. Maintainab. Syrup., Los Angeles, 17-19 January 1978, p. 271. This paper addresses the design and implementation of cost effective reliability tests and is based on work performed by the Airways Facilities of the Federal Aviation Administration (FAA) in their development of a total methodology and data base for reliability and maintainability (R&M) and cost. The objective of the methodology is to minimize LCC by reducing support cost through improved R&M. The methodology provides a systematic and viable approach to R&M based on LCC principles that arc fully in accord with FAA needs. A series of R&M documents are being prepared as part of the effort that completely describes the R&M and cost methodology. These documents provide basic criteria, techniques and step-by-step procedures covering R&M, planning, specification, design, test and control. A key task within the development of the overall methodology is the preparation of the documents covering reliability specification and testing. This paper summarizes the philosophy, approach and some of the elements that were considered in developing these documents. It discusses the reliability testing protocol relative to FAA requirements and the tradeoffs and application factors involved in planning and implementing a completely integrated and cost effective test program. Development of a life cycle management cost model. RAMESH K. BARASIAand T. DAVID KIANG. Proc. IEEE A. Retiab. Maintainab. Syrup., Los Angeles, 17-19 January 1978, p. 254. Bell-Northern Research has developed a

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methodology for carrying out comparative engineering evaluations as an aid to management decision-making. This methodology is unique in that it relates the life cycle cost of a system to a system effectiveness parameter, namely availability. The work was carried out under contract to the Canadian Department of National Defence. The methodology is intended for use by Canadian Forces life cycle material managers in the procurement of new systems, for optimization studies on maintenance, and for logistics support plans for existing systems. The generalized life cycle management cost model can analyze a system that consists of one or more prime equipments situated at one or more locations, and takes into account the maintenance and logistics support provided. This paper presents the results of the development program and case studies undertaken to demonstrate model capability and application.

Contractor initiatives for R&M/cost improvement. C. DAVID WEIML~. Proc. IEEE A. Reliab. Maintainab. Syrnp., Los Angeles, 17-19 January 1978, p. 243. This paper presents a synthesis of major findings and conclusions derived from four years research in electronics subsystems acquisition. Department of Defense policy statements for achieving improved reliability, maintainability, and cost are reviewed. The application and implementation of these policies are examined and the management response of system and subsystem contractors is described in areas of operating policies and procedures, project organization, cost management and control, and development program planning. The contractor experiences during their engineering development programs arc subsequently evaluated in terms of operating problems or policy barriers. In total, the experiences of 43 contractors responding in 25 separate programs are examined and analyzed. Based upon their past experiences and management behavior, the appropriate resp6nse to successfully embrace future policy initiatives is postulated. Program standards help software maintainability. BENJAMIN B. WHITE. Proc. IEEE A. Reliab. Maintainab. Syrup., Los Angeles, 17-19 January 1978, p. 94. In the past fifteen years. data-processing technology has increased the industry's potential for problem solving by several orders of magnitude. .The advances ha.re resulted in progressively more complex computational systems with increasingly greater life expectancy. In the process, software has become a critical element in the maintainability of many complex scientific and business systems. This change has precipitated a need for a systematic, disciplined approach to managing the computer program development and modification cycles. Among the steps being taken by managers in response to this need are the implementation and enforcement of computer programming standards considered to positively affect software maintainability. The purpose of the research reported in this paper was to evaluate to what extent the managers of computer programming efforts are committed to enforcing these standards. The specific research problem was as follows: Does any relationship exist between managers" attitudes toward computer programming standards and the strength of their enforcement of the standards? Reliability growth planning and control. WALTER A. L1LIUS. Proc. IEEE A. Reliab. Maintainab. Syrup., Los Angeles, 17-19 January 1978, p. 267. Reliability growth management in the US Army Materiel Development and Readiness Command (DARCOM) is the application of management planning and control techniques to the achievement of reliability. Two approaches are used in the associated analyses: treatment of the development program as an idealized (smooth) process, and treatment of the development program as a phase-by-phase process. The latter