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AVAILABILITY MODEL FOR SELF TEST AND REPAIR IN FAULT TOLERANT FPGA-BASED SYSTEMS
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作者 Shampa Chakraverty Anubhav Agarwal +1 位作者 Broteen Kundu Anil Kumar 《Journal of Electronics(China)》 2014年第4期271-283,共13页
Dynamically reconfigurable Field Programmable Gate Array(dr-FPGA) based electronic systems on board mission-critical systems are highly susceptible to radiation induced hazards that may lead to faults in the logic or ... Dynamically reconfigurable Field Programmable Gate Array(dr-FPGA) based electronic systems on board mission-critical systems are highly susceptible to radiation induced hazards that may lead to faults in the logic or in the configuration memory. The aim of our research is to characterize self-test and repair processes in Fault Tolerant(FT) dr-FPGA systems in the presence of environmental faults and explore their interrelationships. We develop a Continuous Time Markov Chain(CTMC) model that captures the high level fail-repair processes on a dr-FPGA with periodic online Built-In Self-Test(BIST) and scrubbing to detect and repair faults with minimum latency. Simulation results reveal that given an average fault interval of 36 s, an optimum self-test interval of 48.3 s drives the system to spend 13% of its time in self-tests, remain in safe working states for 76% of its time and face risky fault-prone states for only 7% of its time. Further, we demonstrate that a well-tuned repair strategy boosts overall system availability, minimizes the occurrence of unsafe states, and accommodates a larger range of fault rates within which the system availability remains stable within 10% of its maximum level. 展开更多
关键词 Dynamically reconfigurable Field Programmable Gate Array (dr-FPGA) Built-In self-test (BIST) Fault Tolerance (FT) Single Event Effects (SEEs) Continuous Time Markov Chain (CTMC) ScrubbingCLC number:TN47
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Deterministic Circular Self Test Path 被引量:2
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作者 文科 胡瑜 李晓维 《Tsinghua Science and Technology》 SCIE EI CAS 2007年第S1期20-25,共6页
Circular self test path (CSTP) is an attractive technique for testing digital integrated circuits(IC) in the nanometer era, because it can easily provide at-speed test with small test data volume and short test applic... Circular self test path (CSTP) is an attractive technique for testing digital integrated circuits(IC) in the nanometer era, because it can easily provide at-speed test with small test data volume and short test application time. However, CSTP cannot reliably attain high fault coverage because of difficulty of testing random-pattern-resistant faults. This paper presents a deterministic CSTP (DCSTP) structure that consists of a DCSTP chain and jumping logic, to attain high fault coverage with low area overhead. Experimental re- sults on ISCAS’89 benchmarks show that 100% fault coverage can be obtained with low area overhead and CPU time, especially for large circuits. 展开更多
关键词 very large scale integration (VLSI) test built-in-self-test (BIST) circular self test path DETERMINISTIC
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Uptake of HIV Self-testing among Men Who have Sex with Men in Beijing, China: a Cross-sectional Study 被引量:13
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作者 REN Xian Long WU Zun You +3 位作者 MI Guo Dong MCGOOGAN Jennifer ROU Ke Ming ZHAO Yan 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2017年第6期407-417,共11页
Objective To examine HIV self-testing uptake and its determinates among men who have sex with men (MSM) in Beijing, China. Methods A cross-sectional online survey was conducted in Beijing, China in 2016. Participant... Objective To examine HIV self-testing uptake and its determinates among men who have sex with men (MSM) in Beijing, China. Methods A cross-sectional online survey was conducted in Beijing, China in 2016. Participants were users of a popular Chinese gay networking application and had an unknown or negative HIV status. Univariate and multivariate logistic regression analyses were conducted to examine factors associated with HIV self-testing based on adjusted odds ratio (AOR) and 95% confidence interval (CI). Results Among the 5,996 MSM included in the study, 2,383 (39.7%) reported to have used HIV self-testing kits. Willingness to use an HIV self-test kit in the future was expressed by 92% of the participants. High monthly income (AOR = 1.49; CI = 1.10-2.02; P = 0.010), large number of male sex partners (≥2: AOR = 1.24; CI = 2.09-1.43; P = 0.002), sexual activity with commercial male sex partners (〉 2: AOR = 1.94; CI = 1.34 -2.82; P = 0.001), long-term drug use (AOR = 1.42; CI = 1.23-1.62; P 〈 0.001), and long-term HIV voluntary counseling and testing (VCT) attendance (AOR = 3.62; CI = 3.11-4.22; P 〈 0.001) were all associated with increased odds of HIV self-testing uptake. Conclusion The nearly 40% rate of HIV self-testing uptake among MSM in our sample was high. In addition, an over 90% willingness to use kits in the future was encouraging. HIV self-testing could be an important solution to help China achieve the global target of having 90% of all people living with HIV diagnosed by 2020. 展开更多
关键词 Men who have sex with men HIV self-testing Associated factors BEIJING
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Integration of Tracer Test Data to Refine Geostatistical Hydraulic Conductivity Fields Using Sequential Self-Calibration Method 被引量:5
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作者 胡晓农 蒋小伟 万力 《Journal of China University of Geosciences》 SCIE CSCD 2007年第3期242-256,共15页
On the basis of local measurements of hydraulic conductivity, geostatistical methods have been found to be useful in heterogeneity characterization of a hydraulic conductivity field on a regional scale. However, the m... On the basis of local measurements of hydraulic conductivity, geostatistical methods have been found to be useful in heterogeneity characterization of a hydraulic conductivity field on a regional scale. However, the methods are not suited to directly integrate dynamic production data, such as, hydraulic head and solute concentration, into the study of conductivity distribution. These data, which record the flow and transport processes in the medium, are closely related to the spatial distribution of hydraulic conductivity. In this study, a three-dimensional gradient-based inverse method--the sequential self-calibration (SSC) method--is developed to calibrate a hydraulic conductivity field, initially generated by a geostatistical simulation method, conditioned on tracer test results. The SSC method can honor both local hydraulic conductivity measurements and tracer test data. The mismatch between the simulated hydraulic conductivity field and the reference true one, measured by its mean square error (MSE), is reduced through the SSC conditional study. In comparison with the unconditional results, the SSC conditional study creates the mean breakthrough curve much closer to the reference true curve, and significantly reduces the prediction uncertainty of the solute transport in the observed locations. Further, the reduction of uncertainty is spatially dependent, which indicates that good locations, geological structure, and boundary conditions will affect the efficiency of the SSC study results. 展开更多
关键词 sequential self-calibration tracer test hydraulic conductivity geostatistical simulation inverse problem
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Shake-table testing of a self-centering precast reinforced concrete frame with shear walls 被引量:11
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作者 Lu Xilin Yang Boya Zhao Bin 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2018年第2期221-233,共13页
The seismic performance of a self-centering precast reinforced concrete (RC) frame with shear walls was investigated in this paper. The lateral force resistance was provided by self-centering precast RC shear walls ... The seismic performance of a self-centering precast reinforced concrete (RC) frame with shear walls was investigated in this paper. The lateral force resistance was provided by self-centering precast RC shear walls (SPCW), which utilize a combination ofunbonded prestressed post-tensioned (PT) tendons and mild steel reinforcing bars for flexural resistance across base joints. The structures concentrated deformations at the bottom joints and the unbonded PT tendons provided the self-centering restoring force. A 1/3-scale model of a five-story self-centering RC frame with shear walls was designed and tested on a shake-table under a series of bi-directional earthquake excitations with increasing intensity. The acceleration response, roof displacement, inter-story drifts, residual drifts, shear force ratios, hysteresis curves, and local behaviour of the test specimen were analysed and evaluated. The results demonstrated that seismic performance of the test specimen was satisfactory in the plane of the shear wall; however, the structure sustained inter-story drift levels up to 2.45%. Negligible residual drifts were recorded after all applied earthquake excitations. Based on the shake-table test results, it is feasible to apply and popularize a self-centering precast RC frame with shear walls as a structural system in seismic regions. 展开更多
关键词 self-CENTERING shake-table test RC frame with shear walls PRECAST unbonded post-tensioning seismicperformance
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Robustness self-testing of states and measurements in the prepare-and-measure scenario with 3 → 1 random access code
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作者 Shi-Hui Wei Fen-Zhuo Guo +1 位作者 Xin-Hui Li Qiao-Yan Wen 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第7期144-151,共8页
Recently, Tavakoli et al.proposed a self-testing scheme in the prepare-and-measure scenario, showing that self-testing is not necessarily based on entanglement and violation of a Bell inequality [Phys.Rev.A 98 062307(... Recently, Tavakoli et al.proposed a self-testing scheme in the prepare-and-measure scenario, showing that self-testing is not necessarily based on entanglement and violation of a Bell inequality [Phys.Rev.A 98 062307(2018)].They realized the self-testing of preparations and measurements in an N → 1(N ≥ 2) random access code(RAC), and provided robustness bounds in a 2 → 1 RAC.Since all N → 1 RACs with shared randomness are combinations of 2 → 1 and 3 → 1 RACs, the3 → 1 RAC is just as important as the 2 → 1 RAC.In this paper, we find a set of preparations and measurements in the3 → 1 RAC, and use them to complete the robustness self-testing analysis in the prepare-and-measure scenario.The method is robust to small but inevitable experimental errors. 展开更多
关键词 ROBUSTNESS self-testING prepare-and-measure SCENARIO 3 1 random access CODE
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Assessing the Acceptability and Willingness to Use HIV Self-Testing among Student Nurses in a Private Nursing College, Gauteng Province, South Africa
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作者 Sphiwe Madiba Molly Segobola Mathildah Mokgatle 《World Journal of AIDS》 2015年第3期208-216,共9页
Globally, there is increasing evidence that HIV self-testing (HIVST) is commonly practiced among health care workers (HCWs). Although HIVST kits are available in South Africa, their distribution and use remain unregul... Globally, there is increasing evidence that HIV self-testing (HIVST) is commonly practiced among health care workers (HCWs). Although HIVST kits are available in South Africa, their distribution and use remain unregulated and its acceptability, undocumented. The aim of the study was to explore the acceptability of HIV self-testing among student nurses, examine their willingness to use self-testing, and evaluate their views on the implementation of a regulated HIV self-testing programme. This was a qualitative explorative study, and six focus group discussions were conducted with 67 student nurses recruited from a private nursing college, in Pretoria, South Africa. Thematic analysis and NVivo10 qualitative software were used for data analysis. The nurses perceived HIVST as an acceptable option for HIV testing and most were willing to self-test. Self-testing will provide confidential and accessible HIV testing services, reduce the stigma associated with the condition, and increase partner testing and disclosure. HIVST is more likely to be practised if self-testing kits are easily accessible and affordable, and there are strategies to educate people before the adoption of HIVST. The lack of pre- and post-test counselling, the risk of inaccurate test results, and lack of strategies for the confirmation of self-testing results were the main arguments against HIVST. The high acceptance of HIVST among nurses suggests that HIVST is a feasible option to increase the uptake of HIV-testing among HCWs. However, pre- and post-test counselling should be considered important components in the implementation of self-testing services. Educational and awareness campaigns should precede the roll-out of the self-testing programs. 展开更多
关键词 HIV self-testING Nurses ACCEPTABILITY South AFRICA Health Care Workers
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A note on self-normalized Dickey-Fuller test for unit root in autoregressive time series with GARCH errors 被引量:1
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作者 YANG Xiao-rong ZHANG Li-xin 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2008年第2期197-201,共5页
In this article, the unit root test for AR(p) model with GARCH errors is considered. The Dickey-Fuller test statistics are rewritten in the form of self-normalized sums, and the asymptotic distribution of the test s... In this article, the unit root test for AR(p) model with GARCH errors is considered. The Dickey-Fuller test statistics are rewritten in the form of self-normalized sums, and the asymptotic distribution of the test statistics is derived under the weak conditions. 展开更多
关键词 unit root AR (p)-GARCH (1 1) self-NORMALIZED Dickey-Fuller test statistic.
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HIV Self-Testing Kits Uptake in Mashonaland West Province, Zimbabwe, 2019-2020: A Secondary Data Analysis
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作者 Tendai Hlabangana Owen Mugurungi +5 位作者 Howard Nyika Emmanuel Govha Tsitsi Patience Juru Notion Tafara Gombe Addmore Chadambuka Mufuta Tshimanga 《World Journal of AIDS》 2022年第1期20-31,共12页
Background: Human Immuno-Deficiency Virus Self-Testing (HIVST) is a process where an individual who wants to know their HIV status collects a specimen, performs a test and interprets the result by themselves. HIVST da... Background: Human Immuno-Deficiency Virus Self-Testing (HIVST) is a process where an individual who wants to know their HIV status collects a specimen, performs a test and interprets the result by themselves. HIVST data from the Zimbabwe AIDS and TB Program (ATP) directorate showed that between 2019-2020, only 31% of the target HIVST kits were distributed in the country. Mashonaland West Province was one of the least performing provinces in meeting targets for HIVST kits distribution. Gaps in the implementation of the HIVST in the province ultimately affect the nationwide scaleup of targeted testing, a key enabler in achieving HIV epidemic control. We analyzed HIVST trends in Mashonaland West Province to inform HIV testing services programming. Methods: We conducted a cross-sectional study using HIVST secondary data obtained from the District Health Information Software 2 (DHIS2) electronic database. We conducted regression analysis for trends using Epi Info 7.2 and tables, bar graphs, pie charts and linear graphs were used for data presentation. Results: A total of 31,070 clients accessed HIVST kits in Mashonaland West Province from 2019-2020. A slightly higher proportion (50.4% and 51.7%) of females as compared to males accessed HIVST kits in 2019 and 2020 respectively. Overall, an increase in the trend of HIVST kits uptake was recorded (males R<sup>2</sup> = 0.3945, p-value = 0.003 and females R<sup>2</sup> = 0.4739, p-value = 0.001). There was generally a decline in the trend of community-based distribution of HIVST kits from the third quarter of 2019 throughout 2020 (R<sup>2</sup> = 0.2441, p-value = 0.006). Primary distribution of HIVST kits remained the dominant method of distribution, constituting more than half of the kits distributed in both 2019 (67%) and 2020 (86%). Conclusion: Mashonaland West Province was mainly utilising facility-based distribution model for HIVST over the community-based distribution model. We recommended training more community-based distribution agents to increase community distribution of HIVST kits. 展开更多
关键词 HIV self-testing Analysis Secondary Data
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The Theoretically Studies and Field Testing of Self-Insulation Exterior Wall in the Hot Summer and Cold Winter Zone
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作者 Huifang Yu Quanbiao Xu +2 位作者 Sanming Zhang Weijun Gao Jianfeng Xu 《Energy and Power Engineering》 2017年第10期654-686,共33页
The energy efficiency design of the exterior wall in the buildings of the hot summer and cold winter zone of China should consider the heat prevention in summer and the heat insulation in winter. The self-insulation o... The energy efficiency design of the exterior wall in the buildings of the hot summer and cold winter zone of China should consider the heat prevention in summer and the heat insulation in winter. The self-insulation of the exterior?wall is a more feasible design to satisfy the energy efficiency of buildings in the?zone. However, the systematic research is urgently needed for the self-insulation of the exterior wall in the hot summer and cold winter zone of China. The paper tested the thermal performance of the common non-clay materials such as shale sintered hollow brick, sand autoclaved aerated concrete block, etc. by means of indoor experiments. The energy efficiency effect of the common materials was verified using dynamic calculation soft PKPM and several constitutions of exterior wall with different main bricks and insulation materials on the heat bridge were simulated, too. Besides, the tests of the thermal performance of exterior wall in real constructions were carried out to testify the practical effect of the recommended constitutions of exterior wall with different main bricks and insulation materials on the heat bridge. The conclusions are: the physical and thermal properties of the six non-clay wall material are better than the clay porous brick;the thermal performance of the non-clay brick can be improved obviously through the rational arrangement of the holes;shale sintered hollow brick after increasing the holes and rationalizing the hole arrangement and sand autoclaved aerated concrete block are recommended for buildings in the hot summer and cold winter area of China. The dynamic calculation results show that the thermal performances?of the non-clay materials are all satisfied with the energy efficiency;The heat transfer coefficient of the exterior wall with composition?③,?in which?the main wall was sand autoclaved aerated concrete block and the material on the heat bridge was sand autoclaved aerated concrete plate, is the smallest among the three recommended compositions. 展开更多
关键词 self-INSULATION EXTERIOR Wall INDOOR Experiments Dynamic Simulation Field testing Hot SUMMER and COLD WINTER Zone
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一种将测试集嵌入到Test-per-Clock位流中的方法 被引量:1
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作者 刘铁桥 邝继顺 +1 位作者 蔡烁 尤志强 《计算机研究与发展》 EI CSCD 北大核心 2014年第9期2022-2029,共8页
集成电路测试方案的关键在于测试向量产生器的设计.传统的测试方法在测试向量生成、测试应用的过程中,没有充分利用测试数据位流来构建测试向量,从而造成了测试时间和存储开销的增加.为了减少测试成本,提出了一种基于test-per-clock模... 集成电路测试方案的关键在于测试向量产生器的设计.传统的测试方法在测试向量生成、测试应用的过程中,没有充分利用测试数据位流来构建测试向量,从而造成了测试时间和存储开销的增加.为了减少测试成本,提出了一种基于test-per-clock模式的内建自测试方法.通过对线性移位测试结构的分析,提出了一种递进式的反复测试生成方法:顺序求解输入位流,逆向精简,多次求解以获得更优值,最终将测试集以较小的代价嵌入到test-per-clock位流中.在测试应用时,只需存储求解后的最小输入流,通过控制线性移位的首位从而生成所需的测试集.实验结果表明,在达到故障覆盖率要求的前提下,能显著地减少测试应用时间和存储面积开销. 展开更多
关键词 内建自测试 test-per-clock 测试位流 测试生成 测试开销
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基于Self-Attention-BiLSTM网络的西瓜种苗叶片氮磷钾含量高光谱检测方法 被引量:6
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作者 徐胜勇 刘政义 +3 位作者 黄远 曾雨 别之龙 董万静 《农业机械学报》 EI CAS CSCD 北大核心 2024年第8期243-252,共10页
元素含量无损检测技术可以为植物生长发育的环境精准调控提供关键实时数据。以西瓜苗为例,提出了一种基于图谱特征融合的氮磷钾含量深度学习检测方法。首先,使用高光谱仪拍摄西瓜苗叶片的高光谱图像,使用连续流动化学分析仪测定叶片的3... 元素含量无损检测技术可以为植物生长发育的环境精准调控提供关键实时数据。以西瓜苗为例,提出了一种基于图谱特征融合的氮磷钾含量深度学习检测方法。首先,使用高光谱仪拍摄西瓜苗叶片的高光谱图像,使用连续流动化学分析仪测定叶片的3种元素含量。然后,采用基线偏移校正(BOC)叠加高斯平滑滤波(GF)的光谱预处理方法和随机森林算法(RF)建立预测模型,基于竞争性自适应重加权采样(CARS)和连续投影算法(SPA)2种算法初步筛选出特征波长,再综合考虑波长数和建模精度设计了一种最优波长评价方法,将波长数进一步减少到3~4个。最后,提取使用U-Net网络分割的彩色图像颜色和纹理特征,和光谱反射率特征一起作为输入,基于自注意力机制-双向长短时记忆(Self-Attention-BiLSTM)网络构建了3种元素含量的预测模型。实验结果表明,氮磷钾含量预测的R2分别为0.961、0.954、0.958,RMSE分别为0.294%、0.262%、0.196%,实现了很好的建模效果。使用该模型对另2个品种西瓜进行测试,R2超过0.899、RMSE小于0.498%,表明该模型具有很好的泛化性。该高光谱建模方法使用少量波长光谱即实现了高精度检测,在精度和效率上达成了很好的平衡,为后续便携式高光谱检测装备开发奠定了理论基础。 展开更多
关键词 西瓜苗叶片 元素含量 无损检测 自注意力机制 双向长短时记忆网络 高光谱
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《水泥基渗透结晶型防水材料》国标修订解读
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作者 杨斌 张永明 +3 位作者 戈兵 朱志远 陈斌 王莹 《中国建筑防水》 2026年第1期36-43,共8页
系统介绍了GB/T 18445—2025《水泥基渗透结晶型防水材料》国家标准的修订背景、主要技术内容及实施要点;重点阐述了标准在分类、技术指标、试验方法及耐久性评价等方面的优化调整,特别是对防水剂氯离子含量、收缩率比等关键参数的加严... 系统介绍了GB/T 18445—2025《水泥基渗透结晶型防水材料》国家标准的修订背景、主要技术内容及实施要点;重点阐述了标准在分类、技术指标、试验方法及耐久性评价等方面的优化调整,特别是对防水剂氯离子含量、收缩率比等关键参数的加严,以及自修复能力试验方法的引入等。 展开更多
关键词 水泥基渗透结晶型防水材料 国家标准 抗渗性能 自修复能力 氯离子含量 试验方法 刚性防水
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一种高效的混合Test-Per-Clock测试方法
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作者 刘铁桥 牛小燕 +1 位作者 杨洁 毛峰 《电子与信息学报》 EI CSCD 北大核心 2017年第9期2266-2271,共6页
该文提出了一种基于内建自测试(BIST)的Test-Per-Clock混合模式向量产生方法。测试由两个部分组成:自由线性反馈移位寄存器(LFSR)伪随机测试模式和受控LFSR确定型测试模式。伪随机测试模式用于快速地检测伪随机易测故障,减少确定型数据... 该文提出了一种基于内建自测试(BIST)的Test-Per-Clock混合模式向量产生方法。测试由两个部分组成:自由线性反馈移位寄存器(LFSR)伪随机测试模式和受控LFSR确定型测试模式。伪随机测试模式用于快速地检测伪随机易测故障,减少确定型数据存储。受控LFSR测试模式采用直接存储在ROM中的控制位流对剩余故障产生确定型测试。通过对提出的BIST混合模式测试结构理论分析,提出了伪随机向量的选取方法以及基于受控线性移位确定型测试生成方法。基准电路的仿真结果表明,该方法可以获得完全单固定型故障覆盖率,其测试产生器设计简单且具有良好的稳定性,与其他方法相比,具有较低的测试开销和较短的测试应用时间。 展开更多
关键词 IC测试 内建自测试 test—Per—Clock测试 测试生成
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Test access to deeply embedded analog terminals within an A/MS SoC
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作者 NIARAKI Asli Rahebeh MIRZAKUCHAKI Sattar +1 位作者 NAVABI Zainalabedin RENOVELL Michel 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2007年第10期1543-1552,共10页
This paper presents a standard scalable and reconfigurable design for testability (SR DfT) in order to increase ac- cessibility to deeply embedded A/MS cores and to limit application of costly off-chip mixed-signal te... This paper presents a standard scalable and reconfigurable design for testability (SR DfT) in order to increase ac- cessibility to deeply embedded A/MS cores and to limit application of costly off-chip mixed-signal testers. SR DfT is an oscilla- tion-based wrapper compatible with digital embedded core-based SoC test methodologies. The impact of the optimized oscilla- tion-based wrapper design on MS SoC testing is evaluated in two directions: area and test time. Experimental results are presented for several SoCs from the ITC’02 test benchmarks with inclusion of eight analog filters. 展开更多
关键词 Scalable design for testability (DIT) Reconfigurable architecture Embedded A/MS testing Modular testing Built-in self test (BIST)
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Adding Pseudo-Random Test Sequence Generator in the Test Simulator for DFT Approach
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作者 Afaq Ahmad Dawood Al-Abri Sayyid Samir AI-Busaidi 《Computer Technology and Application》 2012年第7期463-470,共8页
This paper presents modified version of a realistic test tool suitable to Design For Testability (DFT) and Built-ln Self Test (BIST) environments. A comprehensive tool is developed in the form of a test simulator.... This paper presents modified version of a realistic test tool suitable to Design For Testability (DFT) and Built-ln Self Test (BIST) environments. A comprehensive tool is developed in the form of a test simulator. The simulator is capable of providing a required goal of test for the Circuit Under Test (CUT). The simulator uses the approach of fault diagnostics with fault grading procedures to provide the optimum tests. The current version of the simulator embeds features of exhaustive and pseudo-random test generation schemes along with the search solutions of cost effective test goals. The simulator provides facilities of realizing all possible pseudo-random sequence generators with all possible combinations of seeds. The tool is developed on a common Personal Computer (PC) platform and hence no special software is required. Thereby, it is a low cost tool hence economical. The tool is very much suitable for determining realistic test sequences for a targeted goal of testing for any CUT. The developed tool incorporates flexible Graphical User Interface (GUI) procedures and can be operated without any special programming skill. The tool is debugged and tested with the results of many bench mark circuits. Further, this developed tool can be utilized for educational purposes for many courses such as fault-tolerant computing, fault diagnosis, digital electronics, and safe-reliable-testable digital logic designs. 展开更多
关键词 Digital system testing built-in self test design for testability test vector pseudo-random test sequence linear feedbackshift registers fault diagnosis fault collapsing realistic test fault cover iteration.
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回转变距梳齿式杭白菊自走采摘设备设计与试验
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作者 田志远 曾松伟 +2 位作者 金佳东 华路轩 朱浩然 《中国农机化学报》 北大核心 2026年第2期55-62,共8页
为解决杭白菊机械化采摘技术瓶颈,设计一套回转变距式梳齿式杭白菊自走采摘设备。针对杭白菊力学特性和植株特点,确定回转变距梳齿式采摘设备的结构和工作参数;使用UG 10.0对采摘设备的整体结构进行三维建模,完整呈现整体架构,并对车体... 为解决杭白菊机械化采摘技术瓶颈,设计一套回转变距式梳齿式杭白菊自走采摘设备。针对杭白菊力学特性和植株特点,确定回转变距梳齿式采摘设备的结构和工作参数;使用UG 10.0对采摘设备的整体结构进行三维建模,完整呈现整体架构,并对车体以及采摘梳齿关键作业部件进行强度校核分析,确保设备在复杂作业环境下的结构可靠性;在参数优化方面,通过单因素试验初步确定梳齿间隙范围,利用Design—Expert 8.0.6软件中Box—Behnken试验设计方法进行三因素三水平组合试验。根据试验结果方差分析,以采摘率最大、杂质率和破碎率最小为参数优化目标,回归模型方差分析的P值均小于0.01,显著性程度极高,3类评价指标回归模型误差较小,验证模型的有效性和可靠性;基于Design—Expert 8.0.6软件优化求解,获得最优参数组合:梳齿间隙为9 mm、梳齿转速为60 r/min、自走速度为0.5 m/s,在此工况下,采摘率、杂质率和破碎率分别为85.78%、16.77%和2.05%。设备试验过程运行稳定,为杭白菊机械化采摘和产业升级提供重要依据。 展开更多
关键词 杭白菊 机械采摘 回转变距梳齿 自走式 有限元 正交试验
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全砂地质超长桩基础竖向承载力分析及施工技术研究
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作者 左宽 李雨浓 《山西建筑》 2026年第1期118-121,125,共5页
为确定全砂地层条件下大直径超长桩基础的竖向极限承载力,依托某实体工程,对桩径2.0 m、桩长75.0 m的钻孔灌注桩采用双加载箱自平衡静载试验,并结合GTS-NX有限元软件进行数值模拟分析。试验结果显示,试桩竖向极限承载力为97924 kN;数值... 为确定全砂地层条件下大直径超长桩基础的竖向极限承载力,依托某实体工程,对桩径2.0 m、桩长75.0 m的钻孔灌注桩采用双加载箱自平衡静载试验,并结合GTS-NX有限元软件进行数值模拟分析。试验结果显示,试桩竖向极限承载力为97924 kN;数值模拟以桩顶沉降100 mm为标准,得到极限承载力93.21 MN,两者规律一致、数值差异较小,验证了双加载箱自平衡试验结果的准确性。分析表明,试验与模拟的沉降差异源于双荷载箱对桩身完整性的影响及超长桩侧阻弱化现象,据此提出了提升桩顶清渣与桩底注浆效果的施工建议。 展开更多
关键词 桩基础 自平衡试验 全砂地层 竖向承载力 数值模拟 市政工程
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燃气自闭阀泄漏案例分析
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作者 谢巧菊 《煤气与热力》 2026年第1期72-75,共4页
通过调查燃气自闭阀泄漏案例,分析泄漏原因,提出从优化设计(优化壳体密封结构、优化上盖结构)、制程管控、检测拦截方面解决燃气自闭阀泄漏问题。
关键词 自闭阀 泄漏 膜片破损 气密性检测
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多源激励下自走式残膜回收机机架模态分析和结构优化
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作者 李国明 王小瑜 +2 位作者 李涛 彭强吉 康建明 《农机化研究》 北大核心 2026年第3期103-111,共9页
针对自走式残膜回收机作业过程中振动剧烈导致可靠性差的问题,以降低机架振动强度为目标,进行机架有限元模态仿真和物理模态试验,得到机架前6阶固有频率和振型;开展田间试验,利用FFT算法识别机架振动频率,根据振动信号的时域、频域特征... 针对自走式残膜回收机作业过程中振动剧烈导致可靠性差的问题,以降低机架振动强度为目标,进行机架有限元模态仿真和物理模态试验,得到机架前6阶固有频率和振型;开展田间试验,利用FFT算法识别机架振动频率,根据振动信号的时域、频域特征分析多源激励下的机架振动特性;以提高前4阶固有频率为优化目标,基于灵敏度分析确定优化变量,通过MOGA算法对优化方案进行求解,得到优化变量最佳样本组合,达到固有频率避开激励源频率以减小机架振动的效果。结果表明,机架有限元模型与物理模型最大相对误差为3.59%;风机、甩刀和发动机是造成整机振动剧烈的主要激励源,其激励频率和耦合频率接近机架前4阶固有频率而引起机架局部共振;优化后的机架经有限元模型验证,前4阶固有频率分别提高到33.26、44.21、65.44、89.41 Hz,均避开了整机激励源频率和多源耦合频率,机架最大模态位移降幅为42.77%,有效改善了机架振动特性。研究结果可为自走式残膜回收机的结构设计和振动特性分析提供参考。 展开更多
关键词 自走式残膜回收机 模态分析 振动测试 底盘机架
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