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Understanding the spatial representativeness of air quality monitoring network and its application to PM_(2.5)in the China's Mainland 被引量:3
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作者 Ling Su Chanchan Gao +7 位作者 Xiaoli Ren Fengying Zhang Shanshan Cao Shiqing Zhang Tida Chen Mengqing Liu Bingchuan Ni Min Liu 《Geoscience Frontiers》 SCIE CAS CSCD 2022年第3期130-138,共9页
Air pollution has seriously endangered human health and the natural ecosystem during the last decades.Air quality monitoring stations(AQMS)have played a critical role in providing valuable data sets for recording regi... Air pollution has seriously endangered human health and the natural ecosystem during the last decades.Air quality monitoring stations(AQMS)have played a critical role in providing valuable data sets for recording regional air pollutants.The spatial representativeness of AQMS is a critical parameter when choosing the location of stations and assessing effects on the population to long-term exposure to air pollution.In this paper,we proposed a methodological framework for assessing the spatial representativeness of the regional air quality monitoring network and applied it to ground-based PM_(2.5)observation in the mainland of China.Weighted multidimensional Euclidean distance between each pixel and the stations was used to determine the representativeness of the existing monitoring network.In addition,the K-means clustering method was adopted to improve the spatial representativeness of the existing AQMS.The results showed that there were obvious differences among the representative area of 1820 stations in the mainland of China.The monitoring stations could well represent the PM_(2.5)spatial distribution of the entire region,and the effectively represented area(i.e.the area where the Euclidean distance between the pixels and the stations was lower than the average value)accounted for 67.32%of the total area and covered 93.12%of the population.Forty additional stations were identified in the Northwest,North China,and Northeast regions,which could improve the spatial representativeness by 14.31%. 展开更多
关键词 PM_(2.5) Euclidean distance Spatial representativeness China
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A STUDY ON SAMPLING REPRESENTATIVENESS OF IAEA RM SD-M-2/TM MARINE SEDIMENT BY INAA
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作者 彭立新 田伟之 《Nuclear Science and Techniques》 SCIE CAS CSCD 1992年第1期8-12,共5页
The homogeneity of IAEA RM SD-M-2/TM Marine Sediment was tested by INAA. The sampling constants for 6 elements were determined.
关键词 Sampling representativeness Standard REFERENCE material
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Cover Story
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《Journal of Mountain Science》 SCIE CSCD 2024年第2期F0004-F0004,共1页
Traditional villages are cultural heritage sites representing stages of historical development,with unique regional cultural characteristics and significant cultural values,and their preservation should focus on integ... Traditional villages are cultural heritage sites representing stages of historical development,with unique regional cultural characteristics and significant cultural values,and their preservation should focus on integrity,authenticity,and egrity,au continuity,The protection and development of traditional villages should be guided by a scientifically sound approach.Post-disaster reconstruction is a topic of global concen,and trnditional villages,with their special heritage nttributes,face additional demands and obstacles in post-disaster reconstruction.Post-disaster reconstruction of traditional villages is a dynamic process of changing the production and livelihoods of affected residents while restoring and protecting heritage during this process,Concretely,it is urgent to identify thc main problems faced by post-disaster recovery and reconstruction of traditional vil lages based on the heritage attributes,and probes the protection planning design paths and revitalization strategies accor dingly. 展开更多
关键词 DISASTER HERITAGE representing
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Solving Quantum Many-Particle Models with Graph Attention Network
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作者 于启航 林子敬 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第3期7-14,共8页
Deep learning methods have been shown to be effective in representing ground-state wavefunctions of quantum many-body systems,however the existing approaches cannot be easily used for non-square like or large systems.... Deep learning methods have been shown to be effective in representing ground-state wavefunctions of quantum many-body systems,however the existing approaches cannot be easily used for non-square like or large systems.Here.we propose a variational ansatz based on the graph attention network(GAT)which learns distributed latent representations and can be used on non-square lattices. 展开更多
关键词 representing VARIATIONAL QUANTUM
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全球人工智能专家共同探讨挑战、趋势和标准化
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《China Standardization》 2024年第3期58-58,共1页
With the rapid evolution of artificial intelligence(AI)and the race for governments to regulate it,the need for international consensus has never been greater.International standards can be valuable tools in the respo... With the rapid evolution of artificial intelligence(AI)and the race for governments to regulate it,the need for international consensus has never been greater.International standards can be valuable tools in the responsible deployment of AI,representing the needs and requirements of all stakeholders and providing global best practice. 展开更多
关键词 人工智能专家 representing artificial
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The Representativeness of Air Quality Monitoring Sites in the Urban Areas of a Mountainous City
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作者 Minjin MA Yue CHEN +2 位作者 Fan DING Zhaoxia PU Xudong LIANG 《Journal of Meteorological Research》 SCIE CSCD 2019年第2期236-250,共15页
Lanzhou is a typical mountainous city with severe air pollution in northwestern China. This study uses hourly observational data of air pollutants at five air quality monitoring sites in Lanzhou from July to December ... Lanzhou is a typical mountainous city with severe air pollution in northwestern China. This study uses hourly observational data of air pollutants at five air quality monitoring sites in Lanzhou from July to December 2015 to discuss data quality control and the representativeness of the monitoring sites(four urban sites and one suburban site). A fuzzy matrix is applied to study primary air pollutants. The results show that of the six routinely monitored pollutants,the primary pollutant is PM_10 during the study period. Based on lag correlation analysis and one-way analysis of variance, it is concluded that there are redundant observations at the four urban sites for the timely diffusion and transport of air pollutants from the same general area. The coefficient of divergence(COD) method is then used to evaluate the spatial distribution differences, and the primary air pollutant PM_10 shows differences at each site. COD can be used as a positive indicator to describe site representativeness. To evaluate the overall air pollution in the valley, correlation analysis is performed between the PM_10 concentration retrieved from aerosol optical depth satellite data and the concentration from the four urban monitoring sites. Among these, the correlation between the workers' hospital site data and the retrieval data is the highest, passing the 90% confidence level. A new representative evaluation model for air quality monitoring sites, R_s = 0.77 COD + 0.23R_(retrieval), is established by using COD and correlation coefficients between routine observations and satellite retrieval products. From this model, it can be concluded that the biological products institute site in Lanzhou is the most representative site for the evaluation of air pollution out of the four urban air quality monitoring sites from July to December 2015. 展开更多
关键词 mountainous CITIES air QUALITY MONITORING SITE representativeness
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Enduring Importance
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作者 HU FAN 《ChinAfrica》 2024年第4期32-33,共2页
On 5 March,national and global spotlight turned to the Great Hall of the People in Beijing where around 3,000 deputies gathered to open the second session of the 14th National People’s Congress(NPC).Over a span of se... On 5 March,national and global spotlight turned to the Great Hall of the People in Beijing where around 3,000 deputies gathered to open the second session of the 14th National People’s Congress(NPC).Over a span of seven days,the deputies,representing all of China’s ethnic groups,regions and sectors,discussed and decided on a range of issues critical for the country’s development. 展开更多
关键词 representing development. gathered
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Matching Consequences and Causes in Crisis Public Relations
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作者 Douglas Wilbur 《Journalism and Mass Communication》 2023年第3期121-127,共7页
This exploratory study examines the phenomenon of consequence cause matching,which is based on the representativeness heuristic,from cognitive psychology,upon crisis management and public relations.A 2(Large Scale Cri... This exploratory study examines the phenomenon of consequence cause matching,which is based on the representativeness heuristic,from cognitive psychology,upon crisis management and public relations.A 2(Large Scale Crisis vs.Small Scale Crisis)×2(Large Scale Cause vs.Small Scale Cause)mixed factorial design experiment was conducted based upon a hypothetical crisis scenario.This study found initial evidence that consequence cause matching is a phenomenon that can impact the process of attribution for a crisis.It highlights a potential new area of theoretical growth for the situational crisis communication theory. 展开更多
关键词 Public Relations Crisis Communication Situational Crisis Communication Theory representativeness Heuristic.
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Future meteorological drought conditions in southwestern Iran based on the NEX-GDDP climate dataset
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作者 Sakine KOOHI Hadi RAMEZANI ETEDALI 《Journal of Arid Land》 SCIE CSCD 2023年第4期377-392,共16页
Investigation of the climate change effects on drought is required to develop management strategies for minimizing adverse social and economic impacts.Therefore,studying the future meteorological drought conditions at... Investigation of the climate change effects on drought is required to develop management strategies for minimizing adverse social and economic impacts.Therefore,studying the future meteorological drought conditions at a local scale is vital.In this study,we assessed the efficiency of seven downscaled Global Climate Models(GCMs)provided by the NASA Earth Exchange Global Daily Downscaled Projections(NEX-GDDP),and investigated the impacts of climate change on future meteorological drought using Standard Precipitation Index(SPI)in the Karoun River Basin(KRB)of southwestern Iran under two Representative Concentration Pathway(RCP)emission scenarios,i.e.,RCP4.5 and RCP8.5.The results demonstrated that SPI estimated based on the Meteorological Research Institute Coupled Global Climate Model version 3(MRI-CGCM3)is consistent with the one estimated by synoptic stations during the historical period(1990-2005).The root mean square error(RMSE)value is less than 0.75 in 77%of the synoptic stations.GCMs have high uncertainty in most synoptic stations except those located in the plain.Using the average of a few GCMs to improve performance and reduce uncertainty is suggested by the results.The results revealed that with the areas affected by wetness decreasing in the KRB,drought frequency in the North KRB is likely to increase at the end of the 21st century under RCP4.5 and RCP8.5 scenarios.At the seasonal scale,the decreasing trend for SPI in spring,summer,and winter shows a drought tendency in this region.The climate-induced drought hazard can have vast consequences,especially in agriculture and rural livelihoods.Accordingly,an increasing trend in drought during the growing seasons under RCP scenarios is vital for water managers and farmers to adopt strategies to reduce the damages.The results of this study are of great value for formulating sustainable water resources management plans affected by climate change. 展开更多
关键词 climate change meteorological drought Global Climate Models(GCMs) Standard Precipitation Index(SPI) Representative Concentration Pathway(RCP) NASA Earth Exchange Global Daily Downscaled Projections(NEX-GDDP) southwestern Iran
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The Three Cs:China,Culture and Civilization
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作者 ROBERT WALKER 《China Today》 2023年第11期48-51,共4页
Steeped in a civilization featuring inclusivity and peaceful nature,China seeks exchanges and mutual learning among civilizations rather than cultural hegemony.WHILE claiming its preeminent global economic status,Chin... Steeped in a civilization featuring inclusivity and peaceful nature,China seeks exchanges and mutual learning among civilizations rather than cultural hegemony.WHILE claiming its preeminent global economic status,China has also come to assert its equivalent position in world politics and diplomacy,typically representing the interests of the developing world. 展开更多
关键词 mutual typically representing
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Epigenetic patterns in a complete human genome
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作者 Ariel Gershman 《四川生理科学杂志》 2023年第8期1485-1485,共1页
The completion of a telomere-to-telomere human reference genome,T2T-CHM13,has resolved complex regions of the genome,including repetitive and homologous regions.Here,we present a high-resolution epigenetic study of pr... The completion of a telomere-to-telomere human reference genome,T2T-CHM13,has resolved complex regions of the genome,including repetitive and homologous regions.Here,we present a high-resolution epigenetic study of previously unresolved sequences,representing entire acrocentric chromosome short arms,gene family expansions,and a diverse collection of repeat classes.This resource precisely maps CpG methylation(32.28 million CpGs),DNA accessibility,and short-read datasets(166,058 previously unresolved chromatin immunoprecipitation sequencing peaks)to provide evidence of activity across previously unidentified or corrected genes and reveals clinically relevant paralog-specific regulation.Probing CpG methylation across human centromeres from six diverse individuals generated an estimate of variability in kinetochore localization.This analysis provides a framework with which to investigate the most elusive regions of the human genome,granting insights into epigenetic regulation. 展开更多
关键词 representing INSIGHT RESOLVED
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捕梦网
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作者 陈佳(译) 《中学生英语》 2023年第31期14-16,共3页
The dreamcatcher may be the perfect gift for anyone who always has nightmares.对于那些总是做噩梦的人来说,捕梦网可能是最完美的礼物。Dreamcatchers are round.Inside the loop1 thread2 is arranged3 in such a way that resem... The dreamcatcher may be the perfect gift for anyone who always has nightmares.对于那些总是做噩梦的人来说,捕梦网可能是最完美的礼物。Dreamcatchers are round.Inside the loop1 thread2 is arranged3 in such a way that resembles4 a spider’s web.Feathers are attached5 to the bottom.Beads6 are often used.Some choose to have one bead in the middle representing7 the spider.Others prefer to have the hole in the middle empty. 展开更多
关键词 ATTACHED representing CATCH
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A Mechanism For Solidarity
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作者 JOSUKUTTY C.A. 《ChinAfrica》 2023年第8期43-45,共3页
China and India are two major emerging economies and the two most populous countries,representing about a third of the world’s population.A healthy relationship between the two countries is vital for world peace and ... China and India are two major emerging economies and the two most populous countries,representing about a third of the world’s population.A healthy relationship between the two countries is vital for world peace and stability.Under the spirit of peaceful coexistence envisioned by a number of measures,the bilateral relationship has been marked by“seeking common ground while preserving di!erences.”The key channel for further improving bilateral relations in various fields is to have e!ective forums to facilitate cordiality. 展开更多
关键词 PEACE SEEKING representing
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Healthcare Across Borders
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作者 EDWIN NYIRONGO 《ChinAfrica》 2023年第10期44-45,共2页
Due to the shortage of health personnel in Malawi,some communities often find it difficult to access healthcare service.Some of the people most a!ected are those in orphanages,as it’s not easy to find medical personn... Due to the shortage of health personnel in Malawi,some communities often find it difficult to access healthcare service.Some of the people most a!ected are those in orphanages,as it’s not easy to find medical personnel to visit them,resulting in spreading infections and sometimes negative outcomes in critical illness.Matilda Dambula,representing one of the orphanages in the Central Region of Malawi,said she gave up. 展开更多
关键词 SERVICE representing LAW
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PIKFYVE inhibition mitigates disease in models of diverse forms of ALS
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作者 Shu-Ting Hung 《四川生理科学杂志》 2023年第2期274-274,共1页
Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease that results from many diverse genetic causes.Although therapeutics specifically targeting known causal mutations may rescue individual types of... Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease that results from many diverse genetic causes.Although therapeutics specifically targeting known causal mutations may rescue individual types of ALS, these approaches cannottreat most cases since they have unknown genetic etiology. Thus, there is a pressing need for therapeutic strategies that rescuemultiple forms of ALS. Here, we show that pharmacological inhibition of PIKFYVE kinase activates an unconventional proteinclearance mechanism involving exocytosis of aggregation-prone proteins. Reducing PIKFYVE activity ameliorates ALSpathology and extends survival of animal models and patient-derived motor neurons representing diverse forms of ALS includingC9ORF72, TARDBP, FUS, and sporadic. These findings highlight a potential approach for mitigating ALS pathogenesis that doesnot require stimulating macroautophagy or the ubiquitin-proteosome system. 展开更多
关键词 diverse representing AGGREGATION
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基于有限元计算细观力学的RVE库的建立与应用 被引量:7
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作者 吕毅 吕国志 孙龙生 《机械强度》 CAS CSCD 北大核心 2009年第5期851-856,共6页
基于有限元计算细观力学理论,以MSC.PATRAN为平台,利用PCL(PATRAN command language)实现RVE(repr-esentative volume element)的参数化自动建模,建立RVE库,集成相应的细观力学计算程序,一体化预测复合材料宏观性能。通过工程实例,调用... 基于有限元计算细观力学理论,以MSC.PATRAN为平台,利用PCL(PATRAN command language)实现RVE(repr-esentative volume element)的参数化自动建模,建立RVE库,集成相应的细观力学计算程序,一体化预测复合材料宏观性能。通过工程实例,调用RVE库中的平纹编织复合材料RVE,预测平纹编织C/SiC复合材料的宏观弹性模量,对空天飞机全C/SiC复合材料机身襟翼进行静力有限元计算,实现结构材料一体化设计。 展开更多
关键词 有限元计算细观力学 RVE(representative VOLUME element)库 MSC.PATRAN 空天飞机机身襟翼
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Evaluation of yield,stability and adaptability of national winter rapeseed regional trials in the upper Yangtze River region in 2017-2018 被引量:1
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作者 Ze’en Yu Lixia Luo +3 位作者 Fang Zhang Meiyan Hong Xiangxiang Zhang Ruixing Guo 《Oil Crop Science》 2020年第3期121-128,共8页
Rapeseed variety needs to be tested by regional trial in multiple sites for many years before being applied in market in China.Performants of rapeseed were affected by the interaction of sites and varieties.Evaluation... Rapeseed variety needs to be tested by regional trial in multiple sites for many years before being applied in market in China.Performants of rapeseed were affected by the interaction of sites and varieties.Evaluation of regional trials is very important for guiding rapeseed breeding.GGE(genotype main effects and genotypeenvironment interaction)biplot was used to evaluate yield,stability,adaptability,representativeness and discrimination of national winter rapeseed trials in the upper reaches of Yangtze River in 2017-2018.Results showed that the main effects of genotype(G),environment(E)and genotypeenvironment interaction(GE)were significant(P<0.01)for yield.Among them,E accounted for 46.95%total variation on average,G and GE accounted for 19.34%and 33.71%respectively.Eight varieties were found with high-yield,excellent stability and adaptability,including‘Yiyou 29’,‘Xiwang 920’,‘Liyouza 108’,‘Nanyou 546’,‘Dadi 195’,‘Jiayou 1’,‘Huayouza 28’and‘Yuhua 2’.Test sites included Nanchong,Mianyang,Wanzhou,Shuangliu and Chengdu in Sichuan Province and Zunyi together with Guiyang in Guizhou Province were selected for their excellent representativeness and discrimination.These results would provide theoretical basis for rapeseed breeding. 展开更多
关键词 National regional trial GGE biplot High yield Yield stability ADAPTABILITY representativeness DISCRIMINATION
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怀疑的麻疹案例的代表性在尼日利亚的一个南部的区域报导了
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作者 Akinola A Fatiregun Chuks C Odega 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2013年第2期153-156,共4页
【正】Objective:To compare the characteristics of suspected measles cases at the health facilities and to determine the representativeness of the data.Methods:We visited 25 hospitals in the Aniocha Local Government Ar... 【正】Objective:To compare the characteristics of suspected measles cases at the health facilities and to determine the representativeness of the data.Methods:We visited 25 hospitals in the Aniocha Local Government Area(LGA) of Delta State,Nigeria,from which information on reportable diseases was collected.In particular,the suspected measles cases in their registries between January 1,2007,and June 30,2008,were reviewed.We compared the characteristics,including age,sex,location,and month of reporting,of the suspected cases with the LGA surveillance records.Results:In the LGA records,10%cases involved individuals older than 14 years, compared with 20%in the same age group in the health facility records.Based on geographic location,53%of the measles cases among the hospital records came from a single location,in contrast to only 30%of the cases among the LGA records.An analysis considering time revealed that 30%of the cases in the LGA records occurred in August 2007,whereas 20%of hospital cases were reported in February and May 2008 combined.Conclusions:The two record types differed considerably in all of the characteristics used in this comparison. 展开更多
关键词 representativeness of data SUSPECTED MEASLES SURVEILLANCE evaluation NIGERIA
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Does Missing Data in Studies of Hard-to-Reach Populations Bias Results? Not Necessarily
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作者 Anneliese C. Bolland Sara Tomek John M. Bolland 《Open Journal of Statistics》 2017年第2期264-289,共26页
Missing data are always an issue in community-based longitudinal studies, calling into question the representativeness of samples and bias in conclusions, the research has generated. This may be due to the difficulty ... Missing data are always an issue in community-based longitudinal studies, calling into question the representativeness of samples and bias in conclusions, the research has generated. This may be due to the difficulty of implementing random sampling procedures in these studies and/or the inherent difficulty in sampling hard-to-reach segments of the population being studied. In fact, the ability to accurately study hard-to-reach populations in light of potential bias created by missing data remains an open question. In this study, missing data are defined as both failure to interview potential research participants identified in the sampling frame and failure to retain enrolled research participants longitudinally. Using the sample from the Mobile Youth Survey, a multiple-cohort, longitudinal study of adolescents living in highly impoverished neighborhoods in Mobile, Alabama, we examined sample representativeness and dropout to determine whether missing data led to a nonrepresentative, and therefore, biased sample. Results indicate that even though random procedures are not strictly used to draw the sample, (a) the sample appears to be largely representative of the population that was studied, and (b) attrition is largely uncorrelated with characteristics of those who dropped out. This suggests that it is possible to study with validity hard-to reach populations in community settings. 展开更多
关键词 Hard-to-Reach POPULATIONS Missing Data representativeness COMMUNITY-BASED Research
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Analogue and Mixed-Signal Production Test Speed-Up by Means of Fault List Compression
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作者 Nuno Guerreiro Marcelino Santos Paulo Teixeira 《Circuits and Systems》 2013年第5期407-421,共15页
Accurate test effectiveness estimation for analogue and mixed-signal Systems on a Chip (SoCs) is currently prohibitive in the design environment. One of the factors that sky rockets fault simulation costs is the numbe... Accurate test effectiveness estimation for analogue and mixed-signal Systems on a Chip (SoCs) is currently prohibitive in the design environment. One of the factors that sky rockets fault simulation costs is the number of structural faults which need to be simulated at circuit-level. The purpose of this paper is to propose a novel fault list compression technique by defining a stratified fault list, build with a set of “representative” faults, one per stratum. Criteria to partition the fault list in strata, and to identify representative faults are presented and discussed. A fault representativeness metric is proposed, based on an error probability. The proposed methodology allows different tradeoffs between fault list compression and fault representation accuracy. These tradeoffs may be optimized for each test preparation phase. The fault representativeness vs. fault list compression tradeoff is evaluated with an industrial case study—a DC-DC (switched buck converter). Although the methodology is presented in this paper using a very simple fault model, it may be easily extended to be used with more elaborate fault models. The proposed technique is a significant contribution to make mixed-signal fault simulation cost-effective as part of the production test preparation. 展开更多
关键词 TEST FAULT Model FAULT Clustering FAULT Simulation FAULT representativeness Analog MIXED-SIGNAL TEST
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