An efficient design-for-testability （DFT） technique is proposed to achieve low overhead for scan-based delay fault testing. Existing techniques for delay test such as skewed-load or broadside make the test generatio...An efficient design-for-testability （DFT） technique is proposed to achieve low overhead for scan-based delay fault testing. Existing techniques for delay test such as skewed-load or broadside make the test generation process complex and produce lower coverage for scan-based designs as compared with non-scan designs, whereas techniques such as enhanced-scan test can make the test easy but need an extra holding latch to add substantial hardware overhead. A new tri-state holding logic is presented to replace the common holding latch in enhanced-scan test to get a substantial low hardware overhead. This scheme can achieve low delay overhead by avoiding the holding latch on the critical timing scan path. What＇s more, this method can also keep the state and signal activity in the combinational circuit from the scan during data scan-in operation to reduce the power dissipation. Experiment results on a set of ISCAS89 benchmarks show the efficiency of the proposed scheme.展开更多
This paper presents a new BIST method for RTL data paths based on single-control testability, a new concept of testability. The BIST method adopts hierarchical test. Test pattern generators are placed only on primary ...This paper presents a new BIST method for RTL data paths based on single-control testability, a new concept of testability. The BIST method adopts hierarchical test. Test pattern generators are placed only on primary inputs and test patterns are propagated to and fed into each module. Test responses are similarly propagated to response analyzers placed only on primary outputs. For the propagation of test patterns and test responses paths existing in the data path are utilized. The DFT method for the single-control testability is also proposed. The advantages of the proposed method are high fault coverage (for single Stuck-at faults), low hardware overhead and capability of at-speed test. Moreover, test patterns generated by test pattern generators can be fed into each module at consecutive system clocks, and thus, the BIST can also detect some faults of other fault models (e.g., transition faults and delay faults) that require consecutive application of test patterns at speed of system clock.展开更多
In order to improve the system reliability and performance and to reduce the system cost, volume and weight, we have designed, fabricated and tested the multibus adapter system of a trimodular redundant fault tolerant...In order to improve the system reliability and performance and to reduce the system cost, volume and weight, we have designed, fabricated and tested the multibus adapter system of a trimodular redundant fault tolerant computer system on a single chip of 5000 gate CMOS gate array. The design, fabrication and test of this single chip system will be discussed..展开更多
This study presents a Bayesian methodology for de- signing step stress accelerated degradation testing （SSADT） and its application to batteries. First, the simulation-based Bayesian de- sign framework for SSADT is p...This study presents a Bayesian methodology for de- signing step stress accelerated degradation testing （SSADT） and its application to batteries. First, the simulation-based Bayesian de- sign framework for SSADT is presented. Then, by considering his- torical data, specific optimal objectives oriented Kullback-Leibler （KL） divergence is established. A numerical example is discussed to illustrate the design approach. It is assumed that the degrada- tion model （or process） follows a drift Brownian motion; the accele- ration model follows Arrhenius equation; and the corresponding parameters follow normal and Gamma prior distributions. Using the Markov Chain Monte Carlo （MCMC） method and WinBUGS software, the comparison shows that KL divergence is better than quadratic loss for optimal criteria. Further, the effect of simulation outiiers on the optimization plan is analyzed and the preferred sur- face fitting algorithm is chosen. At the end of the paper, a NASA lithium-ion battery dataset is used as historical information and the KL divergence oriented Bayesian design is compared with maxi- mum likelihood theory oriented locally optimal design. The results show that the proposed method can provide a much better testing plan for this engineering application.展开更多
China’s high-speed railways are always facing the potential damage risk induced by strong earthquakes.And the route design concept of“using bridge instead of embankment”has also greatly increased the probability of...China’s high-speed railways are always facing the potential damage risk induced by strong earthquakes.And the route design concept of“using bridge instead of embankment”has also greatly increased the probability of high speed trains moving on bridges when a strong earthquake happens.In the past decades,a bunch of theoretical and numerical studies have been conducted in the seismic dynamic field of high-speed railway.However,the effective dynamic test system for verifying the given method and theoretical results is still lacking.Therefore,a novel dynamic test system(DTS)consisting of a shaking table array and a train-pass-bridge reduced-scale model is proposed in this paper.Through some crucial technical problems discussion,the effectiveness of similar design scheme and the feasibility of reduced-scale DTS are elaborated,and then the detailed DTS structures are given and displayed as part-by-part.On this basis,the demonstration tests are conducted and compared with the numerical simulation.The results show that the proposed DTS is accurate and effective.Therefore,the DTS can provide a new physical simulation approach to study the high-speed train’s running safety on bridges under earthquakes and can also provide a reference for the construction of related systems.展开更多
In order to provide relay communication supports for future Chinese lunar exploration program,Queqiao-2 relay communication satellite was developed.Queqiao-2 can perform scientific observations with three kinds of sci...In order to provide relay communication supports for future Chinese lunar exploration program,Queqiao-2 relay communication satellite was developed.Queqiao-2 can perform scientific observations with three kinds of scientific instruments on board.The system design of Queqiao-2,including mission orbit and transfer orbit design,configuration and layout design,housekeeping and information flow design,power supply and distribution design,GNC and propulsion system design,communication links design,etc.,was accomplished through comprehensive tradeoff and evaluation on technical maturity,availability,schedule,cost,and so on.With a view to reducing development risk,both the platform and relay communication payloads were developed based on significant heritage from previous Queqiao relay satellite and other relevant spacecraft.Queqiao-2 features flexible system architecture to support multiple frequencies,modulations,data rates and software reconfigurations to meet new user requirements.Subsequent to a successful launch on March 20,2024,by means of 5 orbit maneuvers,Queqiao-2 was inserted into a highly elliptical frozen mission orbit around the moon with a 24h period on schedule.Following on-orbit tests and calibrations,Queqiao-2 has possessed the capacity to provide reliable relay communication services to multiple lunar exploration missions,as well as the capacity to perform scientific observations.Under the support of Queqiao-2,Chang′e-6 achieved its ambitious mission goal to collect and return samples from the moon′s mysterious far side.In the meanwhile,Queqiao-2 has also paved the way for the following Chinese lunar exploration missions including Chang′e-7 and Chang′e-8.The design life time of Queqiao-2 is more than 8 years.Benefit from flexibility and extensibility of relay communication system design,it is convenient to provide relay communication services for future lunar exploration missions of both China and other countries.In addition,innovative scientific observations would be performed during the period that no relay communication task is arranged.The system design of Queqiao-2 reflects the development philosophy of technical innovations and inheritance integration.Based on highly flexible and extensible system architecture,multiple and concurrent relay communication mission requirements can be met.It can provide strong supports for future lunar exploration missions.Successful launching,orbit entering and on-orbit tests of Queqiao-2 verified the correct design principle and versatility.By means of Queqiao-2,more innovative scientific outcomes are anticipated and lunar exploration activities can be facilitated.展开更多
With the development of VLSI technology, testing design method has been one indispensable fact of the research of VLSI design methodology. Technology of testing design can observably reduce the cost of the chip and he...With the development of VLSI technology, testing design method has been one indispensable fact of the research of VLSI design methodology. Technology of testing design can observably reduce the cost of the chip and help win in time- to-market. Conventional methods of design for test improve the testing performance of the system by modifing the gate-level architecture generally. Re-search in high-level test synthesis has been emphasized on fitting for the trend of high-level VLSI design. In this paper, based on the analysis of different types of testing design methods, a novel compound strategy of design for test in VLSI system is proposed.展开更多
The analysis method of the triple test cross design has been discussed carefully from the two factor experiment design and the genetic models of additive dominant effect and of epistasis effect.Two points different f...The analysis method of the triple test cross design has been discussed carefully from the two factor experiment design and the genetic models of additive dominant effect and of epistasis effect.Two points different from the previous reports have been concluded: (1)both the degrees of freedom of the orthogonal terms C2 and C3 are m, (2)the denominator in the F test to C2 and C3 is the error mean of square between plots.展开更多
The test scheme of static postponing time given in our actual national military test standard on shrapnels used to control riot is a nine-point test scheme on the combined action of three kinds of temperatures and thr...The test scheme of static postponing time given in our actual national military test standard on shrapnels used to control riot is a nine-point test scheme on the combined action of three kinds of temperatures and three kinds of pressures, the consumed ammunitions are more excessive. Statistic analysis and tentative checkout about a lot of test data are done, feasibility gists are put forward for optimizing of the test design scheme. The optimizing design and data analysis of test scheme of the item are done by managing uniformity design theory, two scientific and reasonable six-point test schemes are confirmed. The feasibility and reliability of the optimizing design schemes put forward above are proved ulteriorly by test validating. The gained schemes not only have good design uniformity and little ammunition wastage and meet the test demand, but also have better forecast ability for the result data of other points using the mathematic models from the actual test points.展开更多
NOx and soot emissions from diesel engines can be greatly reduced by pressure wave supercharging(PWS).The diesel engine matched with PWS needs redesigning its exhaust pipes.Except for meeting the installation requirem...NOx and soot emissions from diesel engines can be greatly reduced by pressure wave supercharging(PWS).The diesel engine matched with PWS needs redesigning its exhaust pipes.Except for meeting the installation requirements,the exhaust gas must be stable in pressure before rushing into PWS.In this paper the lateral and center ported divergent exhaust pipes are designed,modeled geometrically and analyzed structurally based on a 3-D design software-CATIA to determine the structure of two exhaust pipes having the required inner volume.Then flow analysis for two exhaust pipes is done using a flow analysis software-ANASYS.Moreover,the optimal exhaust pipes are determined comprehensively and cast for engine test.Engine test results show that PWS is superior to turbocharging at low engine speeds and inferior to turbocharging in power and emissions at medium-to-high engine speeds.The performance of PWS engine under high speed operating conditions can be improved by contriving larger surge volume intake and exhaust pipes.展开更多
基金This project was supported by the National Natural Science Foundation of China (90407007).
文摘An efficient design-for-testability （DFT） technique is proposed to achieve low overhead for scan-based delay fault testing. Existing techniques for delay test such as skewed-load or broadside make the test generation process complex and produce lower coverage for scan-based designs as compared with non-scan designs, whereas techniques such as enhanced-scan test can make the test easy but need an extra holding latch to add substantial hardware overhead. A new tri-state holding logic is presented to replace the common holding latch in enhanced-scan test to get a substantial low hardware overhead. This scheme can achieve low delay overhead by avoiding the holding latch on the critical timing scan path. What＇s more, this method can also keep the state and signal activity in the combinational circuit from the scan during data scan-in operation to reduce the power dissipation. Experiment results on a set of ISCAS89 benchmarks show the efficiency of the proposed scheme.
文摘This paper presents a new BIST method for RTL data paths based on single-control testability, a new concept of testability. The BIST method adopts hierarchical test. Test pattern generators are placed only on primary inputs and test patterns are propagated to and fed into each module. Test responses are similarly propagated to response analyzers placed only on primary outputs. For the propagation of test patterns and test responses paths existing in the data path are utilized. The DFT method for the single-control testability is also proposed. The advantages of the proposed method are high fault coverage (for single Stuck-at faults), low hardware overhead and capability of at-speed test. Moreover, test patterns generated by test pattern generators can be fed into each module at consecutive system clocks, and thus, the BIST can also detect some faults of other fault models (e.g., transition faults and delay faults) that require consecutive application of test patterns at speed of system clock.
文摘In order to improve the system reliability and performance and to reduce the system cost, volume and weight, we have designed, fabricated and tested the multibus adapter system of a trimodular redundant fault tolerant computer system on a single chip of 5000 gate CMOS gate array. The design, fabrication and test of this single chip system will be discussed..
基金supported by the National Natural Science Foundation of China(61104182)
文摘This study presents a Bayesian methodology for de- signing step stress accelerated degradation testing （SSADT） and its application to batteries. First, the simulation-based Bayesian de- sign framework for SSADT is presented. Then, by considering his- torical data, specific optimal objectives oriented Kullback-Leibler （KL） divergence is established. A numerical example is discussed to illustrate the design approach. It is assumed that the degrada- tion model （or process） follows a drift Brownian motion; the accele- ration model follows Arrhenius equation; and the corresponding parameters follow normal and Gamma prior distributions. Using the Markov Chain Monte Carlo （MCMC） method and WinBUGS software, the comparison shows that KL divergence is better than quadratic loss for optimal criteria. Further, the effect of simulation outiiers on the optimization plan is analyzed and the preferred sur- face fitting algorithm is chosen. At the end of the paper, a NASA lithium-ion battery dataset is used as historical information and the KL divergence oriented Bayesian design is compared with maxi- mum likelihood theory oriented locally optimal design. The results show that the proposed method can provide a much better testing plan for this engineering application.
基金Projects(51878674,52108433,52022113) supported by the National Natural Science Foundation of ChinaProject(2019RS3009) supported by the Hunan Innovative Provincial Construction,China+2 种基金Project(2021JJ40587) supported by the Hunan Provincial Natural Science Foundation of ChinaProject(21B0309) supported by the Research Foundation of Education Bureau of Hunan Province,ChinaProject(HSR202004) supported by the Open Foundation of National Engineering Research Center of High-Speed Railway Construction Technology,China。
文摘China’s high-speed railways are always facing the potential damage risk induced by strong earthquakes.And the route design concept of“using bridge instead of embankment”has also greatly increased the probability of high speed trains moving on bridges when a strong earthquake happens.In the past decades,a bunch of theoretical and numerical studies have been conducted in the seismic dynamic field of high-speed railway.However,the effective dynamic test system for verifying the given method and theoretical results is still lacking.Therefore,a novel dynamic test system(DTS)consisting of a shaking table array and a train-pass-bridge reduced-scale model is proposed in this paper.Through some crucial technical problems discussion,the effectiveness of similar design scheme and the feasibility of reduced-scale DTS are elaborated,and then the detailed DTS structures are given and displayed as part-by-part.On this basis,the demonstration tests are conducted and compared with the numerical simulation.The results show that the proposed DTS is accurate and effective.Therefore,the DTS can provide a new physical simulation approach to study the high-speed train’s running safety on bridges under earthquakes and can also provide a reference for the construction of related systems.
文摘In order to provide relay communication supports for future Chinese lunar exploration program,Queqiao-2 relay communication satellite was developed.Queqiao-2 can perform scientific observations with three kinds of scientific instruments on board.The system design of Queqiao-2,including mission orbit and transfer orbit design,configuration and layout design,housekeeping and information flow design,power supply and distribution design,GNC and propulsion system design,communication links design,etc.,was accomplished through comprehensive tradeoff and evaluation on technical maturity,availability,schedule,cost,and so on.With a view to reducing development risk,both the platform and relay communication payloads were developed based on significant heritage from previous Queqiao relay satellite and other relevant spacecraft.Queqiao-2 features flexible system architecture to support multiple frequencies,modulations,data rates and software reconfigurations to meet new user requirements.Subsequent to a successful launch on March 20,2024,by means of 5 orbit maneuvers,Queqiao-2 was inserted into a highly elliptical frozen mission orbit around the moon with a 24h period on schedule.Following on-orbit tests and calibrations,Queqiao-2 has possessed the capacity to provide reliable relay communication services to multiple lunar exploration missions,as well as the capacity to perform scientific observations.Under the support of Queqiao-2,Chang′e-6 achieved its ambitious mission goal to collect and return samples from the moon′s mysterious far side.In the meanwhile,Queqiao-2 has also paved the way for the following Chinese lunar exploration missions including Chang′e-7 and Chang′e-8.The design life time of Queqiao-2 is more than 8 years.Benefit from flexibility and extensibility of relay communication system design,it is convenient to provide relay communication services for future lunar exploration missions of both China and other countries.In addition,innovative scientific observations would be performed during the period that no relay communication task is arranged.The system design of Queqiao-2 reflects the development philosophy of technical innovations and inheritance integration.Based on highly flexible and extensible system architecture,multiple and concurrent relay communication mission requirements can be met.It can provide strong supports for future lunar exploration missions.Successful launching,orbit entering and on-orbit tests of Queqiao-2 verified the correct design principle and versatility.By means of Queqiao-2,more innovative scientific outcomes are anticipated and lunar exploration activities can be facilitated.
文摘With the development of VLSI technology, testing design method has been one indispensable fact of the research of VLSI design methodology. Technology of testing design can observably reduce the cost of the chip and help win in time- to-market. Conventional methods of design for test improve the testing performance of the system by modifing the gate-level architecture generally. Re-search in high-level test synthesis has been emphasized on fitting for the trend of high-level VLSI design. In this paper, based on the analysis of different types of testing design methods, a novel compound strategy of design for test in VLSI system is proposed.
文摘The analysis method of the triple test cross design has been discussed carefully from the two factor experiment design and the genetic models of additive dominant effect and of epistasis effect.Two points different from the previous reports have been concluded: (1)both the degrees of freedom of the orthogonal terms C2 and C3 are m, (2)the denominator in the F test to C2 and C3 is the error mean of square between plots.
文摘The test scheme of static postponing time given in our actual national military test standard on shrapnels used to control riot is a nine-point test scheme on the combined action of three kinds of temperatures and three kinds of pressures, the consumed ammunitions are more excessive. Statistic analysis and tentative checkout about a lot of test data are done, feasibility gists are put forward for optimizing of the test design scheme. The optimizing design and data analysis of test scheme of the item are done by managing uniformity design theory, two scientific and reasonable six-point test schemes are confirmed. The feasibility and reliability of the optimizing design schemes put forward above are proved ulteriorly by test validating. The gained schemes not only have good design uniformity and little ammunition wastage and meet the test demand, but also have better forecast ability for the result data of other points using the mathematic models from the actual test points.
文摘NOx and soot emissions from diesel engines can be greatly reduced by pressure wave supercharging(PWS).The diesel engine matched with PWS needs redesigning its exhaust pipes.Except for meeting the installation requirements,the exhaust gas must be stable in pressure before rushing into PWS.In this paper the lateral and center ported divergent exhaust pipes are designed,modeled geometrically and analyzed structurally based on a 3-D design software-CATIA to determine the structure of two exhaust pipes having the required inner volume.Then flow analysis for two exhaust pipes is done using a flow analysis software-ANASYS.Moreover,the optimal exhaust pipes are determined comprehensively and cast for engine test.Engine test results show that PWS is superior to turbocharging at low engine speeds and inferior to turbocharging in power and emissions at medium-to-high engine speeds.The performance of PWS engine under high speed operating conditions can be improved by contriving larger surge volume intake and exhaust pipes.
