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Reliability activities for Bell System transmission systems
WORLD
ABSTRACTS
ON MICROELECTRONICS
c c m p m y is honorable in its short- mui Ions-term warranty cornmitments; then the rewards from doing bnsine~ in the medical equipment field are unlimited, Corporate growth of 20-25 per vent per year is a reasonable goal for this product are~ If the basic precepts outlined above are violated, however, the path to an economic disinter is a certainw! In our present litigationoriented society, lack of product reliability can only remdt in a painful courtroom drama at some future date I l~Halbility a c t i v i t l ~ for Bell S y l t e m ~ W. G. ALm¢~, J. T. BaNom~r and L . H . STrums. ~ # of the 1972 AJmua/Rd/ab///ty am/ M ~ Sympe6um, San Francisco. I E E E Cat. No. 72CH0577-7R. 25-27 January (1972), p. 278. This paper covers the comprehemive Bell System reliability activities that parallel the engineering and development of current and future long haul transmission systems over coaxial cable. In addition, data gathering techniques and a computer aided reliabih'ty program based on units rctumed for repair are covered, Reltlddlity o f t h e global N A S C O M n e t w o r k . L . R . STSLTn. Proceedings of the 1972 Aroma/Rd/a/db'ty and Maintainabih'ty Sympodum, San Francisco. I E E E Cat. No. 72CH0577-7R. 25-27 January (1972), p. 272. Transmission media reliability is an e~t~-,ely important factor in the design and operation of a real-time cornmunicationa network. It has had a profound effect not only on the configuration design of the N A S C O M network itself, but on the philosophy of command/control of all N A S A spacecraft, manned and unmanned. In an effort to obtain the highest possible level of circuit reliability and performance, goals or criteria have been established for each type of circuit. Also, speciai management techniques have been used in an effort to improve circuit reliability. T h e results of these efforts, as well as general technological improvements in the trammi~ion media, are illustrated by showing measured composite circuit reliability over the past 9 yr and actual circuit performance measured during Apollo 8 through 15. Reliability o f all t r m a ~ t t o r i z e d c o l o r t e l e v i ~ o n K. NUK~0A and A. MtY~OTO. Procesdingt of the Second Sympo:/um on Rel/ab///ty, JUSE, Tokyo, Japan. 17-18 April (1972), p. 203. (In Japanese.) Hitachi Ltd. developed high reliability-all transistorized color television sets with the field data analysis concerning all transistorized hlack and white television sets and tube type color television sets and with the know-how on reliability. The causes of the breakdown of the transistors used in color television sets are; the damage by high voltage-, high energy-pulses, for example, and different from those of other electronic apparatus. For this reason, we analyzed the field date of the brokendown transistors using the method of Weibull distribution and we made the following clear: (I) The high voltage-, high energy-pulses appear incidentally. So, m (Weibull distribution shape parameter) equals I for the breakdown of the transistors by this failure mode. (2) For the specific breakdown of the transistors, m<~l.
AND RELIABILITY
481
Therefore, we presume that these pulses came the brinkdown to the tmndato~ under the normal operation of color television sets, which cannot be revealed by the ordinary test of transistors, and we made the countermeasure to it. S l m l d e IC m m t ~ ~ circuit atmmlz~ 100 a A m p , full4male. M. V ~ o n Koox, EDN/EEE, 15 April (1972), P" 40" A P rogramable ° p a-mp~-, a ~ of components and two flashlight batteries are all you need to make ultra-~msitive voltage and current me~urements. T h e reliability p r o g r a m o f t h e a i r b o r n e e O m l m t o r CK37. B / J r s w e r r z . Proceed_~,qs of the 1972 Aroma/ and M ~ 8 y m p o d m , San Francisco. I E E E Cat. No. 72CH0577-7R. 25-27 January (1972), p. 158. This paper describes a reliability program which was started in1963 in connection with the development of an airborne computer (CK37) for the Swedish aircraft SAAB 37 " V I G G E N " . The general-purpme computer, now in serial production, also includes an input-output unit which transfers analog and binary aignals to joint operating equipment in the data handlin8 system of the aircraft. A total of 42,500 operating hours from seven computer prototypes have been accumulated up to the end of 1970. All operative failures have been recorded and analyzed. This has given a total failure rate of 600--850 failures/10' hr (60% CL) referred to the ground operating mode. The demonstrated failure rate of these prototype computers is of the same magnitude as was predicted for the serial production units during the early prototype design phase. T h e reliability m t ~ t n e e r in t h e h e l d t h c a r e ~ y ~ m . E . F . TAYLOR.Proceed/ng$ of the 1972 Aroma/Re//ab//ity and Maintainability Sympodum, San Francisco. I E E E Cat. No. 72CH0577-7R. 25-27 January (1972), p. 245. T h e professional reliability engineer has had limited success in applying his available expertise to the health care system. On the other hand, the health care professional is plagued by reliability problems especially in medical electronic equipment. This paper discusses some of the reasons why these two professionals have been unable to match available resources with the problems to be solved. Recommendations are made to both on actions to be taken toward solvingthe medical equipment reliability problem for the benefit of the ultimate consumer--the patient. R e l i a b i l i t y e v a l u a t l o n o f st h e a r t mmist s y s t e m . D . F . SIMONAITIS, R. T. AtmEasoN and M. P. K A y . Proceedings of the 1972 Ammal Re'lmbility and Maintainab///ty ~qympos/um, San Francisco. I E E E Cat. No. 72CH0577-7R. 25-27 January (1972), p. 233. This paper discusses the reliability and safety aspects of a program for the engineering evaluation of a medical device intended to provide circulatory assistance following myocardial infarction. The purpose of this evaluation is to provide assurance that the hardware implementation of the device concept will meet criteria necessary for safe and effective clinical testing.
ABSTRACTS
ON MICROELECTRONICS
c c m p m y is honorable in its short- mui Ions-term warranty cornmitments; then the rewards from doing bnsine~ in the medical equipment field are unlimited, Corporate growth of 20-25 per vent per year is a reasonable goal for this product are~ If the basic precepts outlined above are violated, however, the path to an economic disinter is a certainw! In our present litigationoriented society, lack of product reliability can only remdt in a painful courtroom drama at some future date I l~Halbility a c t i v i t l ~ for Bell S y l t e m ~ W. G. ALm¢~, J. T. BaNom~r and L . H . STrums. ~ # of the 1972 AJmua/Rd/ab///ty am/ M ~ Sympe6um, San Francisco. I E E E Cat. No. 72CH0577-7R. 25-27 January (1972), p. 278. This paper covers the comprehemive Bell System reliability activities that parallel the engineering and development of current and future long haul transmission systems over coaxial cable. In addition, data gathering techniques and a computer aided reliabih'ty program based on units rctumed for repair are covered, Reltlddlity o f t h e global N A S C O M n e t w o r k . L . R . STSLTn. Proceedings of the 1972 Aroma/Rd/a/db'ty and Maintainabih'ty Sympodum, San Francisco. I E E E Cat. No. 72CH0577-7R. 25-27 January (1972), p. 272. Transmission media reliability is an e~t~-,ely important factor in the design and operation of a real-time cornmunicationa network. It has had a profound effect not only on the configuration design of the N A S C O M network itself, but on the philosophy of command/control of all N A S A spacecraft, manned and unmanned. In an effort to obtain the highest possible level of circuit reliability and performance, goals or criteria have been established for each type of circuit. Also, speciai management techniques have been used in an effort to improve circuit reliability. T h e results of these efforts, as well as general technological improvements in the trammi~ion media, are illustrated by showing measured composite circuit reliability over the past 9 yr and actual circuit performance measured during Apollo 8 through 15. Reliability o f all t r m a ~ t t o r i z e d c o l o r t e l e v i ~ o n K. NUK~0A and A. MtY~OTO. Procesdingt of the Second Sympo:/um on Rel/ab///ty, JUSE, Tokyo, Japan. 17-18 April (1972), p. 203. (In Japanese.) Hitachi Ltd. developed high reliability-all transistorized color television sets with the field data analysis concerning all transistorized hlack and white television sets and tube type color television sets and with the know-how on reliability. The causes of the breakdown of the transistors used in color television sets are; the damage by high voltage-, high energy-pulses, for example, and different from those of other electronic apparatus. For this reason, we analyzed the field date of the brokendown transistors using the method of Weibull distribution and we made the following clear: (I) The high voltage-, high energy-pulses appear incidentally. So, m (Weibull distribution shape parameter) equals I for the breakdown of the transistors by this failure mode. (2) For the specific breakdown of the transistors, m<~l.
AND RELIABILITY
481
Therefore, we presume that these pulses came the brinkdown to the tmndato~ under the normal operation of color television sets, which cannot be revealed by the ordinary test of transistors, and we made the countermeasure to it. S l m l d e IC m m t ~ ~ circuit atmmlz~ 100 a A m p , full4male. M. V ~ o n Koox, EDN/EEE, 15 April (1972), P" 40" A P rogramable ° p a-mp~-, a ~ of components and two flashlight batteries are all you need to make ultra-~msitive voltage and current me~urements. T h e reliability p r o g r a m o f t h e a i r b o r n e e O m l m t o r CK37. B / J r s w e r r z . Proceed_~,qs of the 1972 Aroma/ and M ~ 8 y m p o d m , San Francisco. I E E E Cat. No. 72CH0577-7R. 25-27 January (1972), p. 158. This paper describes a reliability program which was started in1963 in connection with the development of an airborne computer (CK37) for the Swedish aircraft SAAB 37 " V I G G E N " . The general-purpme computer, now in serial production, also includes an input-output unit which transfers analog and binary aignals to joint operating equipment in the data handlin8 system of the aircraft. A total of 42,500 operating hours from seven computer prototypes have been accumulated up to the end of 1970. All operative failures have been recorded and analyzed. This has given a total failure rate of 600--850 failures/10' hr (60% CL) referred to the ground operating mode. The demonstrated failure rate of these prototype computers is of the same magnitude as was predicted for the serial production units during the early prototype design phase. T h e reliability m t ~ t n e e r in t h e h e l d t h c a r e ~ y ~ m . E . F . TAYLOR.Proceed/ng$ of the 1972 Aroma/Re//ab//ity and Maintainability Sympodum, San Francisco. I E E E Cat. No. 72CH0577-7R. 25-27 January (1972), p. 245. T h e professional reliability engineer has had limited success in applying his available expertise to the health care system. On the other hand, the health care professional is plagued by reliability problems especially in medical electronic equipment. This paper discusses some of the reasons why these two professionals have been unable to match available resources with the problems to be solved. Recommendations are made to both on actions to be taken toward solvingthe medical equipment reliability problem for the benefit of the ultimate consumer--the patient. R e l i a b i l i t y e v a l u a t l o n o f st h e a r t mmist s y s t e m . D . F . SIMONAITIS, R. T. AtmEasoN and M. P. K A y . Proceedings of the 1972 Ammal Re'lmbility and Maintainab///ty ~qympos/um, San Francisco. I E E E Cat. No. 72CH0577-7R. 25-27 January (1972), p. 233. This paper discusses the reliability and safety aspects of a program for the engineering evaluation of a medical device intended to provide circulatory assistance following myocardial infarction. The purpose of this evaluation is to provide assurance that the hardware implementation of the device concept will meet criteria necessary for safe and effective clinical testing.