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A hybrid algorithm based on ILP and genetic algorithm for time-aware test case prioritization 被引量:1
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作者 Sun Jiaze Wang Gang 《Journal of Southeast University(English Edition)》 EI CAS 2018年第1期28-35,共8页
To solve the problem of time-awarc test case prioritization,a hybrid algorithm composed of integer linear programming and the genetic algorithm(ILP-GA)is proposed.First,the test case suite which cm maximize the number... To solve the problem of time-awarc test case prioritization,a hybrid algorithm composed of integer linear programming and the genetic algorithm(ILP-GA)is proposed.First,the test case suite which cm maximize the number of covered program entities a d satisfy time constraints is selected by integer linea progamming.Secondly,the individual is encoded according to the cover matrices of entities,and the coverage rate of program entities is used as the fitness function and the genetic algorithm is used to prioritize the selected test cases.Five typical open source projects are selected as benchmark programs.Branch and method are selected as program entities,and time constraint percentages a e 25%and 75%.The experimental results show that the ILP-GA convergence has faster speed and better stability than ILP-additional and IP-total in most cases,which contributes to the detection of software defects as early as possible and reduces the software testing costs. 展开更多
关键词 test case prioritization integer linear programming(I LP) genetic algorithm time constraint
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Topographic tear film trend and new parameters for noninvasive break up time test
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作者 Yakup Acet 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2022年第12期1932-1939,共8页
AIM:To evaluate the quantitative and qualitative results of the noninvasive tear film break-up time(NI-BUT)test and investigate the predictive ability of the new NIBUT parameter in discriminating between normal Ocular... AIM:To evaluate the quantitative and qualitative results of the noninvasive tear film break-up time(NI-BUT)test and investigate the predictive ability of the new NIBUT parameter in discriminating between normal Ocular Surface Disease Index(OSDI;scores≤12)and abnormal OSDI(scores≥13).METHODS:A total of 341 eyes of 341 volunteers who applied for routine eye outpatient control were included in the prospective study.All participants'noninvasive first tear film break-up time(NIF-BUT),noninvasive average tear film break-up time(NIAvg-BUT)and average value of the first three break-up time(A3F-BUT)were analyzed.A3F-BUT,the new NI-BUT parameter,is calculated by adding the NIF-BUT value to the 2^(nd )break-up time value that has a difference of at most 1 second from the NIF-BUT value and to the 3^(rd) break-up time and then dividing the respective sum by 3.Receiver operating characteristic(ROC)curve and forward logistic regression analyses were performed to determine the parameter that had the best predictive ability between the OSDI groups.RESULTS:The NI-BUT values of 255 eyes of 255 volunteers included in the study were analyzed statistically.The mean NIF-BUT,NIAvg-BUT,and A3F-BUT values were calculated as 5.3±3.0,8±3.1,and 5.8±3.0 seconds,respectively.All three parameters were found to be significantly lower in the abnormal OSDI group(P=0.014,0.034,and 0.011,respectively).The area under the curve(AUC)of the A3F-BUT to predict abnormal OSDI was AUC=0.625(0.529-0.720),P=0.011 and NIF-BUT was AUC=0.599(0.502-0.696),P=0.043.The A3F-BUT parameter and NIF-BUT parameters were found to be significantly efficient in discriminating abnormal OSDI.CONCLUSION:The new parameter for the NI-BUT test has more predictive ability in the discrimination of OSDI groups. 展开更多
关键词 noninvasive break-up time Ocular Surface Disease Index tear film topographic break-up time test
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Shaking table tests and dynamic analyses of masonry wall buildings with frame-shear walls at lower stories 被引量:4
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作者 Xiong Lihong David Xiong +1 位作者 Wu Ruifeng Xia Jingqian 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2008年第3期271-283,共13页
This paper describes shaking table tests of three eight-story building models: all are masonry structures in the upper stories, with or without frame-shear walls of one- or two- stories at the bottom. The test result... This paper describes shaking table tests of three eight-story building models: all are masonry structures in the upper stories, with or without frame-shear walls of one- or two- stories at the bottom. The test results of damage characteristics and seismic responses are provided and compared. Then, nonlinear response analyses are conducted to examine the reliability of the dynamic analysis. Finally, many nonlinear response analyses are performed and it is concluded that for relatively hard sites under a certain lateral stiffness ratio (i.e., the ratio of the stiffness of the lowest upper masonry story to that of the frame- shear wall story), the masonry structure with one-story frame-shear wall at the bottom performs better than a structure built entirely of masonry, and a masonry structure with frame-shear wall of two stories performs better than with one-story frame- shear wall. In relatively soft soil conditions, all three structures have similar performane. In addition, some suggestions that could be helpful for design of masonry structures with ground story of frame-shear wall structure in seismic intensity region VII, such as the appropriate lateral stiffness ratio, shear force increase factor of the frame-shear wall story, and permissible maximum height of the building, are proposed. 展开更多
关键词 masonry structure soft story seismic performance shaking table test nonlinear time history analysis
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Validity of subjective assessment as screening tool for dry eye disease and its association with clinical tests 被引量:2
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作者 Kavita R Bhatnagar Sonali Pote +1 位作者 Sudeep Pujari Dhiraj Deka 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2015年第1期174-181,共8页
AIM: To determine the role of subjective assessment using Mc Monnies dry eye questionnaire in diagnosing dry eye disease and its association with clinical tests.METHODS: There were 500 patients screened for dry eye us... AIM: To determine the role of subjective assessment using Mc Monnies dry eye questionnaire in diagnosing dry eye disease and its association with clinical tests.METHODS: There were 500 patients screened for dry eye using Mc Monnies dry eye questionnaire between May to October 2013 at the outpatient Department of Ophthalmology of a medical college hospital. All 500 patients were subjected to clinical tests. Dry eye was defined as having one or more symptoms often or all the time. Positive signs were if one or both eyes revealed tear film breakup time(TBUT) of ≤10s, a Schirmer test score of ≤10 mm, a Rose Bengal staining score of ≥1, a Lissamine green staining score of ≥1 or existence of meibomian gland disease(≥grade 1). Statistical analysis was performed to describe the distribution of symptoms and signs, to assess the correlations between Mc Monnies score(MS) and variable clinical signs of dry eye, and to explore the association between dry eye symptoms and variable clinical signs. Analysis was performed using software package Epi info. A Probability(P) value using Chi-square test of 【0.005 was taken as significant.· RESULTS: Dry eye prevalence with symptoms(questionnaire), Schirmer test, TBUT, Rose Bengal staining and Lissamine green staining was 25.6%,15.20%, 20.80%, 23.60%, and 22.60% respectively. Among those with severe symptoms(MS】20), 75.86% had a low TBUT(【10s), 58.62% had a low Schirmer’s I test(≤10 mm),86.20% had Rose Bengal staining score of ≥1, 79.31%had Lissamine green staining score of ≥1. We found statistically significant associations between positive Schirmer test and arthritis(P 【0.002), dryness elsewhere(P 【0.001), contact lens use(P 【 0.002), systemic medication(P 【0.0001), sleeping with eyes partly open(P 【0.002), history of dry eyes treatment(P 【0.0001),environmental factors(P 【0.001), swimming(P 【0.001).· CONCLUSION: Subjective assessment plays an important role in diagnosing dry eye disease. There is strong correlation between MS and Schirmer test, TBUT,Rose Bengal staining and Lissamine green staining in normal as well as marginal and pathological dry eye. 展开更多
关键词 Mc Monnies dry eye questionnaire Schirmer test tear film breakup time test Rose Bengal staining Lissamine green staining
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Sensitivity Test and Data Analysis for Storage Reliability Assessment of Explosive Initiator 被引量:2
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作者 洪东跑 赵宇 《Defence Technology(防务技术)》 SCIE EI CAS 2010年第2期119-125,共7页
The explosive initiator is one kind of sensitivity products with long life and high reliability.In order to improve the storage reliability assessment,the method of storage reliability assessment for explosive initiat... The explosive initiator is one kind of sensitivity products with long life and high reliability.In order to improve the storage reliability assessment,the method of storage reliability assessment for explosive initiator was proposed based on time series model using the sensitivity test data.In the method,the up and down test was used to estimate the distribution parameters of threshold.And an approach to design the up and down test was present to draw better estimations.Furthermore,the method of shrinkage estimation was introduced to get a better estimation of scale parameter by combining the sample information with prior information.The simulation result shows that the shrinkage estimation is better than traditional estimation under certain conditions.With the distribution parameters estimations,the time series models were used to describe the changing trends of distribution parameters along with storage time.Then for a fixed storage time,the distribution parameters were predicted based on the models.Finally,the confidence interval of storage reliability was obtained by fiducial inference.The illustrative example shows that the method is available for storage reliability assessment of the explosive initiator with high reliability. 展开更多
关键词 system engineering storage reliability explosive initiator up and down test time series model shrinkage estimation
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Detecting the Relationship Between Summer Rainfall Anomalies in Eastern China and the SSTA in the Global Domain with a New Significance Test Method 被引量:4
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作者 LU Chuhan GUAN Zhaoyong WANG Panxing DUAN Mingken 《Journal of Ocean University of China》 SCIE CAS 2009年第1期15-22,共8页
It is suggested that the multiple samples in a correlation map or a set of correlation maps should be examined with significance tests as per the Bernoulli probability model. Therefore, both the contemporaneous and la... It is suggested that the multiple samples in a correlation map or a set of correlation maps should be examined with significance tests as per the Bernoulli probability model. Therefore, both the contemporaneous and lag correlations of summertime precipitation R in any one of the three regions of Northern China (NC), the Changjiang-Huaihe River Valley (CHRV), and Southern China (SC) with the SSTA in the global domain have been tested in the present article, using our significance test method and the method proposed by Livezey and Chen (1983) respectively. Our results demonstrate that the contemporaneous correlations of sum- mer R in CHRV with the SSTA are larger than those in NC. Significant correlations of SSTA with CHRV R are found to be in some warm SST regions in the tropics, whereas those of SSTA with NC R, which are opposite in sign as compared to the SSTA-CHRVR correlations, are found to be in some regions where the mean SSTs are low. In comparison with the patterns of the contemporaneous correlations, the 1 to 12 month lag correlations between NC R and SSTA, and those between CHRV summer R and SSTA show similar patterns, including the magnitudes and signs, and the spatial distributions of the coefficients. However, the summer rainfall in SC is not well correlated with the SSTA, no matter how long the lag interval is. The results derived from the observations have set up a relationship frame connecting the precipitation anomalies in NC, CHRV, and SC with the SSTA in the global domain, which is critically useful for our understanding and predicting the climate variabilities in different parts of China. Both NC and CHRV summer R are connected with E1 Nifio events, showing a ‘- -'pattern in an E1 Nifio year and a‘+ +' pattern in the subsequent year. Key words summer precipitation; eastern China; global sea surface 展开更多
关键词 temperature contemporaneous correlation time lag correlation significance test for multiple correlation maps
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Research on characters of surrounding rock in complex geology conditions and supporting time 被引量:9
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作者 Yu Weijian Gao Qian +1 位作者 Zhai Shuhua Zhang Meihua 《Engineering Sciences》 EI 2008年第2期91-96,共6页
The methods combined by test, field monitoring and theoretical analysis were adopted to do the systemic research on the rock mass from micro-structure to macro-deformation, and rheological model of Jinchuan rock mass ... The methods combined by test, field monitoring and theoretical analysis were adopted to do the systemic research on the rock mass from micro-structure to macro-deformation, and rheological model of Jinchuan rock mass was established to discuss the reasonable supporting time. Resuhs show that supporting after suitable stress and displacement release can benefit for the long-term stability of surrounding rock. 展开更多
关键词 complex geological conditions surrounding rock characteristic test supporting time theological characteristic
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A test sequence generation method of zone controller based on timed automata 被引量:4
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作者 SONG Shuang CHEN Yue-dong 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2019年第3期266-276,共11页
In order to solve the problem of artificial generation and low efficiency of test sequences for zone controller (ZC), a model-based automatic generation method of test sequence is proposed. Firstly, the timed automata... In order to solve the problem of artificial generation and low efficiency of test sequences for zone controller (ZC), a model-based automatic generation method of test sequence is proposed. Firstly, the timed automata model is established based on function analysis of the zone controller, and the correctness of the model is verified by UPPAAL. Then by parsing the timed automata model files, state information and transition conditions can be extracted to generate test case sets. Finally, according to the serialization conditions of test cases, the test cases are serialized into test sequences by using the improved depth first search algorithm. A case, the ZC controls the train running within its jurisdiction, shows that the method is correct and can effectively improve the efficiency of test sequence generation. 展开更多
关键词 test sequence zone controller (ZC) timed automata model file parsing case serialization
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The effect of urine pregnancy testing on timing of accessing antenatal care and abortion services in Western Nigeria 被引量:1
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作者 Mustafa Adelaja Lamina 《Open Journal of Obstetrics and Gynecology》 2013年第6期486-492,共7页
Objective: Effective confirmation of pregnancy is a basic component of reproductive health services. It is a determinant for accessing antenatal care (ANC) if the pregnancy is wanted and abortion services if the pregn... Objective: Effective confirmation of pregnancy is a basic component of reproductive health services. It is a determinant for accessing antenatal care (ANC) if the pregnancy is wanted and abortion services if the pregnancy is unwanted. This study examined the effect of urine pregnancy testing in the timing of presentation for pregnancy care. Method: A cross-sectional study was conducted among 320 women presenting for antenatal care and 300 women presenting for abortion at private sector clinics in Western Nigeria. Results: The median age at first presentation was 20 weeks for ANC clients and 8 weeks for abortion clients. Obtaining urine pregnancy test of one’s accord was associated with a decrease in the gestational age at presentation of 3.7 weeks and 1.5 weeks for antenatal and abortion clients, respectively, independent of all other factors. Conclusion: Bearing in mind that the clinical benefit and public health impact of early presentation for antenatal and abortion services are unequivocal, strategies aimed at decreasing gestational age at presentation for pregnancy care should be given priority. “Fast-track” urine pregnancy testing services should be promoted in the private and public clinics in Nigeria. 展开更多
关键词 URINE PREGNANCY testing TIMING Accessing ANTENATAL ABORTION
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Delayed Gastric Emptying in Anorexic Adolescents Measured with the <sup>13</sup>C Octanoic Acid Breath Test 被引量:1
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作者 Martine K. F. Docx Kristin Verbeke +4 位作者 Annik Simons Joost Weyler José Ramet Luc Mertens Gigi Veereman-Wauters 《Food and Nutrition Sciences》 2012年第8期1043-1047,共5页
Many gastrointestinal complaints and motility disorders are described in patients suffering from different eating disorders. These have a negative impact on refeeding. This report evaluated–on admission-gastric empty... Many gastrointestinal complaints and motility disorders are described in patients suffering from different eating disorders. These have a negative impact on refeeding. This report evaluated–on admission-gastric emptying of a standardized solid meal with 13C octanoic acid breath test in anorexic adolescents. The results were compared with age and gender matched controls. Gastric emptying data were related to a subjective symptom score. 21 Anorexic girls and 3 boys (mean age: 15.6 y ± 1.3 y), body mass index (mean 15.6 kg/m2 ± 1.6 kg/m2), weight loss (mean: 22.2% ± 10.7%) were studied. T? of the gastric emptying time exceeded the P95 in 14/24 (58%) patients, classified as having delayed gastric emptying (DGE). One patient (4%) had a T? exceeding P75 and was classified as slow (SGE), whereas 9/24 (38%) patients had normal gastric emptying (NGE). In comparison to NGE, subjects with DGE had significantly higher symptom scores (p = 0.01) and more weight loss. The DGE and SGE patients lost 25.29% and 21.38% of weight respectively, whereas a weight loss of 17.64% was found in anorexics with NGE. In conclusion, gastric emptying is delayed in patients with anorexia. This is associated with more significant gastrointestinal symptoms and higher weight loss. 展开更多
关键词 ANOREXIA Nervosa Half-Gastric EMPTYING Time 13C Octanoic Acid BREATH test SUBJECTIVE Severity SYMPTOM Score
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Changes in reaction time, coefficient of variance of reaction time, and autonomic nerve function in the mental fatigue state caused by long-term computerized Kraepelin test workload in healthy volunteers 被引量:1
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作者 Daisuke Kuratsune Seiki Tajima +10 位作者 Junichi Koizumi Kouzi Yamaguti Tetsuya Sasabe Kei Mizuno Masaaki Tanaka Naoko Okawa Hideki Mito Hirokazu Tsubone Yasuyoshi Watanabe Masayasu Inoue Hirohiko Kuratsune 《World Journal of Neuroscience》 2012年第2期113-118,共6页
Fatigue is a common sense caused by crushing labor, stressful social events and various illnesses. It is usually judged by their subjective symptoms, but it should be evaluated in an objective perspective. Here we sho... Fatigue is a common sense caused by crushing labor, stressful social events and various illnesses. It is usually judged by their subjective symptoms, but it should be evaluated in an objective perspective. Here we show that the decrease of working efficiency and sympathetic hyperactivity are associated with mental fatigue state caused by prolonged mental workload. Recently we made a new mental fatigue model of healthy volunteers caused by long-term computerized Kraepelin test (CKT) workload. CKT is our new software for automatically checking the calculation capability, with which it is easy to determine the reaction time (RT), coefficient of variance of reaction time (CV), and accuracy of the answers (AC) during tasks. We put 24 healthy volunteers into the fatigue state by subjecting them to 120 minutes’ CKT workload, and then studied the changes in fatigue sensation, RT, CV, and AC before and after the CKT workload. The fatigue sensation, RT, and CV were clearly increased by the fatigue-inducing task and recovered during the resting period. We also studied the changes in autonomic nerve activity by using heart rate variability analysis. The low/high frequency component ratio (LF/HF) was signifi-cantly increased by the fatigue-inducing task and decreased by resting, suggesting that mental stress causes a relatively sympathetic nerve activity-dominant state. Therefore, our new fatigue model involving a long-term CKT workload is a good mental fatigue model to provide much information about the fatigue state simultane-ously, and the increase of RT, CV, and proportion of sympathetic activity (LF/HF) are associated with mental fatigue state. These might be useful objective biomarkers or evaluating a mental fatigue state. 展开更多
关键词 Fatigue COMPUTERIZED Kraepelin test Reaction Time Accuracy of the ANSWERS AUTONOMIC NERVE Activity
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Statistical Properties and Confidence Limits about the Mean Time between the Failures (MTBF) in Failure-free Period Life Test (FFPLT)
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作者 王庆成 《Chinese Quarterly Journal of Mathematics》 CSCD 2001年第1期9-19,共11页
On the basis of strict mathematical description about Failure_Free Period Life Test (FFPLT), the statistical properties of the tests and optimal confidence limit of the parameter are discussed in detail and correspond... On the basis of strict mathematical description about Failure_Free Period Life Test (FFPLT), the statistical properties of the tests and optimal confidence limit of the parameter are discussed in detail and corresponding calculating formulae are found out. 展开更多
关键词 FFPLT MTBF operating characteristic (OC) function expected test time (ETT) maximum likelihood estimation lower confidence limit
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A Study of Visual Event-Related Potential and Reaction Time in Elderly People: Comparative Analysis of the Scores of Intelligence Test in 30 Subjects
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作者 杨文俊 潘速跃 《Journal of Medical Colleges of PLA(China)》 CAS 1990年第3期222-226,共5页
The results of visual event-related potential(ERP)examinations and reactiontime(RT)tests were reported in 30 elders and compared with their performanceintellegence quotient(PIQ)scores.The subjects consisted of 18 male... The results of visual event-related potential(ERP)examinations and reactiontime(RT)tests were reported in 30 elders and compared with their performanceintellegence quotient(PIQ)scores.The subjects consisted of 18 males and 12 femalesaged 50-71(mean 61.4)years old.No history of central nervous system disease wasfound.The visual stimuli were randomly presented to the subject,including three sym-bols:E as target stimulus with 0.15 probability,and H and E as nontarget stimuliwith 0.15 and 0.70 probability respectively.The recording electrodes were placed on Fzand Pz.The duration from the subject seeing the target to touching a button immediatelywas considered as reaction time(RT).It was shown that the P3 latency at Pz was longer than that at Fz and the P3amplitude at Pz was larger than that at Fz,and that the RT was longer than P3 latencywith obvious effect of distribution(P【0.05 at Fz and P】0.05 at Pz)as well .The higherthe PIQ scores,the longer the RT and the P3 latency.It is suggested that the ERPmight reflect the differences of PIQ scores,and the P3 is an objective index.We considerthat the research of ERP is of great interest in the neuropsychological and neurological sci-ences. 展开更多
关键词 ELDER EVENT-RELATED potential REACTION time INTELLIGENCE test
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Area-time associated test cost model for SoC and lower bound of test time
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作者 张金艺 翁寒一 +1 位作者 黄徐辉 蔡万林 《Journal of Shanghai University(English Edition)》 CAS 2011年第1期43-48,共6页
A novel test access mechanism (TAM) architecture with multi test-channel (TC) based on IEEE Standard 1500 is proposed instead of the traditional sub-TAM structure. The cost model of an area-time associated test an... A novel test access mechanism (TAM) architecture with multi test-channel (TC) based on IEEE Standard 1500 is proposed instead of the traditional sub-TAM structure. The cost model of an area-time associated test and the corresponding lower bound of system-on-chip (SoC) test time are established based on this TAM architecture. The model provides a more reliable method to control the SoC scheduling and reduces the complexity in related algorithm research. The result based on the area time associated test cost model has been validated using the ITC02 test benchmark. 展开更多
关键词 system-on-chip design for testability (SoC DriP) test cost test time lower bound
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Detection and attribution of abrupt climate changes in the last one hundred years 被引量:3
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作者 张文 万仕全 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第6期2311-2316,共6页
Based on physical backgrounds, the four time series of the Guliya (Tibetan plateau) ice core (GIC) 5180, and three natural factors, i.e. the rotation rate of earth, sunspots, and E1 Nino-Southern Oscillation (ENS... Based on physical backgrounds, the four time series of the Guliya (Tibetan plateau) ice core (GIC) 5180, and three natural factors, i.e. the rotation rate of earth, sunspots, and E1 Nino-Southern Oscillation (ENSO) signals, are decomposed into two hierarchies, i.e. more and less than 10-year hierarchies respectively, and then the running t-test is used to reanalyse the data before and after filtering with the purpose of investigating the contribution of natural factors to the abrupt climate changes in the last one hundred years. The results show that the GIC 5180 evolved with a quasi-period of 7-9 years, and the abrupt climate changes in the early 1960s and in the period from the end of the 1970s to the beginning of the 1980s resulted from the joint effect of the two hierarchies, in other words, the two interdecadal abrupt changes of climate in the last one hundred years were global. The interannual variations of ENSO and sunspots were the important triggering factors for the abrupt climate changes in the last one hundred years. At the same time, the method of Information Transfer (IT) is employed to estimate the contributions of ENSO signals and sunspots activities to the abrupt climate changes, and it is found that the contribution of the interannual variation of ENSO signals is relatively large. 展开更多
关键词 abrupt climate change time series analysis running t-test
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CORE-UNIFIED SOC TEST DATA COMPRESSION AND APPLICATION
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作者 Yi Maoxiang Guo Xueying +2 位作者 Liang Huaguo Wang Wei Zhang Lei 《Journal of Electronics(China)》 2010年第1期79-87,共9页
The pattern run-length coding test data compression approach is extended by introducing don't care bit(x) propagation strategy into it.More than one core test sets for testing core-based System-on-Chip(SoC) are un... The pattern run-length coding test data compression approach is extended by introducing don't care bit(x) propagation strategy into it.More than one core test sets for testing core-based System-on-Chip(SoC) are unified into a single one,which is compressed by the extended coding technique.A reconfigurable scan test application mechanism is presented,in which test data for multiple cores are scanned and captured jointly to make SoC test application more efficient with low hardware overhead added.The proposed union test technique is applied to an academic SoC embedded by six large ISCAS'89 benchmarks,and to an ITC' 02 benchmark circuit.Experiment results show that compared with the existing schemes in which a core test set is compressed and applied independently of other cores,the proposed scheme can not only improve test data compression/decompression,but also reduce the redundant shift and capture cycles during scan testing,decreasing SoC test application time effectively. 展开更多
关键词 System-on-Chip(SoC) test application time Pattern run-length X-propagation Union test RECONFIGURATION
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Delay-dependent stability and added damping of SDOF real-time dynamic hybrid testing 被引量:14
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作者 Chi Fudong Wang Jinting Jin Feng 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2010年第3期425-438,共14页
It is well-recognized that a transfer system response delay that reduces the test stability inevitably exists in real-time dynamic hybrid testing (RTDHT). This paper focuses on the delay-dependent stability and adde... It is well-recognized that a transfer system response delay that reduces the test stability inevitably exists in real-time dynamic hybrid testing (RTDHT). This paper focuses on the delay-dependent stability and added damping of SDOF systems in RTDHT. The exponential delay term is transferred into a rational fraction by the Pad6 approximation, and the delay-dependent stability conditions and instability mechanism of SDOF RTDHT systems are investigated by the root locus technique. First, the stability conditions are discussed separately for the cases of stiffness, mass, and damping experimental substructure. The use of root locus plots shows that the added damping effect and instability mechanism for mass are different from those for stiffness. For the stiffness experimental substructure case, the instability results from the inherent mode because of an obvious negative damping effect of the delay. For the mass case, the delay introduces an equivalent positive damping into the inherent mode, and instability occurs at an added high frequency mode. Then, the compound stability condition is investigated for a general case and the results show that the mass ratio may have both upper and lower limits to remain stable. Finally, a high-emulational virtual shaking table model is built to validate the stability conclusions. 展开更多
关键词 real-time dynamic hybrid testing root locus analysis delay-dependent stability Pade approximation added damping
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Prevalence of Dry Eye and Its Association with Various Risk Factors in Rural Setup of Western Uttar Pradesh in a Tertiary Care Hospital
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作者 Ravi Ranjan Sushil Kumar Shukla +3 位作者 Chandra Veer Singh B. N. Mishra Sriti Sinha B. D. Sharma 《Open Journal of Preventive Medicine》 2016年第1期57-63,共7页
Purpose: To study the prevalence of dry eye in a hospital based population of rural setup and to evaluate its association with various risk factors. Material and Methods: In this cross sectional study, patients above ... Purpose: To study the prevalence of dry eye in a hospital based population of rural setup and to evaluate its association with various risk factors. Material and Methods: In this cross sectional study, patients above 20 years of age were screened randomly for dry eye. An 8 points questionnaires, slit lamp examination of meibomian glands, tear film breakup time, fluorescein staining of cornea, schirmer test were used to diagnose dry eye. The diagnosis was made when three of the five parameters were positive. The role of various occupations as well as role of different exposure factors like sunlight, excessive wind, smoking, drugs, and air pollution as dry eye risk factors was accessed. Result: Out of 445, 45.39% patients had dry eye. Dry eye prevalence was higher in those above 70 years of age (74%). It was higher in male population (51.82%) compare to female population (37.37%), nearly equal in rural (46.04%) and urban population (44.31%) and highest among factory workers (90%). Correlation of dry eye with drugs (P = 0.0002), sunlight/high temperature (P = 0.0003) and smoking (P = 0.03) were significant. Conclusion: This is a hospital based study which provides prevalence of dry eye in rural region of western Uttar Pradesh. It is more common in old age male population and significantly higher in factory workers. Out of different modifiable risk factors most important are drugs, sunlight/high temperature and smoking. 展开更多
关键词 Dry Eye Fluorescein Stain Schirmer test Tear Film Break up Time
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Validation and Implementation of the Lactate Minimum Test in Rowing
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作者 Claudio Perret Andrea Vrana 《Journal of Sports Science》 2014年第2期81-89,共9页
LMT (lactate minimum test) was found to be a valid and reliable testing concept for different sport disciplines. The aim of this study was to implement and validate the LMT in rowing due to considerable advantages f... LMT (lactate minimum test) was found to be a valid and reliable testing concept for different sport disciplines. The aim of this study was to implement and validate the LMT in rowing due to considerable advantages for athletes and coaches compared to other established testing concepts in rowing. Twenty healthy and experienced male rowers completed two LMTs, one 2,000 m all-out trial and several endurance tests for MLSS (maximal lactate steady-state) determination on a rowing ergometer. For all tests performance, VO2, heart rate and lactate concentration were monitored. CV (coefficients of variation) for performance, heart rate and VO2 were all below 3.5% indicating a high reproducibility for these parameters at LM (lactate minimum) as well as at LMTpeak. Only lactate concentrations were revealed not to be well reproducible (CV 〉 12%). Performance at LM and MLSS showed a significant correlation (r2 = 0.660; P 〈 0.001). Comparison between data at LMTpeak and the 2,000 m time trial revealed a high correlation between performance and VO2peak data (performance: r2 = 0.923; P 〈 0.001, VO2peak: r2 = 0.860; P 〈 0.001). We conclude that the present LMT protocol allows assessment of VO2peak, MLSS and prediction of 2,000 m race performance based on one single test. Therefore, our LMT protocol represents a reliable and valid diagnostic tool for steering and monitoring the training process in rowing. 展开更多
关键词 testing REPRODUCIBILITY time trial TRAINING performance EXERCISE coaching.
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Liver test abnormalities in asymptomatic and mild COVID-19 patients and their association with viral shedding time
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作者 Si-Yi Yu Jia-Rong Xie +4 位作者 Jun-Jun Luo Hong-Peng Lu Lei Xu Jun-Jie Wang Xue-Qin Chen 《World Journal of Hepatology》 2022年第11期1953-1963,共11页
BACKGROUND Asymptomatic infections and mild symptoms are common in patients infected with the Omicron variant,and data on liver test abnormalities are rare.AIM To evaluated the clinical characteristics of asymptomatic... BACKGROUND Asymptomatic infections and mild symptoms are common in patients infected with the Omicron variant,and data on liver test abnormalities are rare.AIM To evaluated the clinical characteristics of asymptomatic and mild coronavirus disease 2019(COVID-19)patients with abnormal liver test results.METHODS This retrospective study included 661 laboratory-confirmed asymptomatic and mild COVID-19 patients who were treated in two makeshift hospitals in Ningbo from April 5,2022 to April 29,2022.Clinical information and viral shedding time were collected,and univariate and multivariate logistic regression models were performed in statistical analyses.RESULTS Of the 661 patients,83(12.6%)had liver test abnormalities,and 6(0.9%)had liver injuries.Abnormal liver tests revealed a reliable correlation with a history of liver disease(P<0.001)and a potential correlation with male sex and obesity(P<0.05).Elevated alanine aminotransferase was reliably associated with obesity(P<0.05)and a history of liver disease(P<0.001).Elevated aspartate transaminase(AST)was reliably correlated with a history of liver disease(P<0.001),and potentially correlated with age over 30 years(P<0.05).There was a reliable correlation between AST≥2×the upper limit of normal and a longer viral shedding time,especially in mild cases.CONCLUSION Obesity and a history of liver disease are risk factors for liver test abnormalities.Being male and an older age are potential risk factors.Attention should be given to liver tests in asymptomatic and mild COVID-19 patients,which has crucial clinical significance for evaluating the viral shedding time. 展开更多
关键词 COVID-19 Liver test abnormalities Asymptomatic carriers Mild cases Viral shedding time Risk factors
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