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《英语国家概况》辅导(19)——Sample Test 4
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作者 裘实 《英语知识》 2000年第7期28-30,共3页
一、单项选择题(25%) Read the following unfinished statements or ques-tions carefully. For each unfinished statement or ques-tion four suggested answers A, B, C and D are given.Choose the one you think best completes ... 一、单项选择题(25%) Read the following unfinished statements or ques-tions carefully. For each unfinished statement or ques-tion four suggested answers A, B, C and D are given.Choose the one you think best completes the statementor answers the question:1.The British Empire gradually disappeared and it was replaced by the____. 展开更多
关键词 《英语国家概况》 sample test 4 英语知识
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《英语国家概况》辅导(20) Sample Test 4(英文)
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作者 裘实 《英语知识》 2000年第8期27-29,共3页
四、名词解释(15%)Explain the following terms in English:1.Jazz 2.Fianna Fail3.Counterculture 4.The Privy Council5.“Quiet Revolution”五、简答题(12%)Give brief answers to the following questions;1.What do you know abo... 四、名词解释(15%)Explain the following terms in English:1.Jazz 2.Fianna Fail3.Counterculture 4.The Privy Council5.“Quiet Revolution”五、简答题(12%)Give brief answers to the following questions;1.What do you know about the“public schools”in the UK?2.What are the powers of the U.S.President?3.What is meant bv the term“welfare state”inBritain? 展开更多
关键词 《英语国家概况》 名词解释 sample test 4
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Comparison of Two Sample Tests Using Both Relative Efficiency and Power of Test
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作者 Edith Uzoma Umeh Nkiru Obioma Eriobu 《Open Journal of Statistics》 2016年第2期331-345,共15页
This paper, comparison of two sample tests, is motivated by the fact that in the test of significant difference between two independent samples, numerous methods can be adopted;each may lead to significant different r... This paper, comparison of two sample tests, is motivated by the fact that in the test of significant difference between two independent samples, numerous methods can be adopted;each may lead to significant different results;this implies that wrong choice of test statistic could lead to erroneous conclusion. To prevent misleading information, there is a need for proper investigation of some selected methods for test of significant difference between variables/subjects most especially, independent samples. The paper examines the efficiency and sensitivity of four test statistics to ascertain which test performs better. Based on the results, the relative efficiency favours median test as being more efficient than modified median test for both symmetric and asymmetric distributions. In terms of power of test, median test is more sensitive than Modified Median (MMED) test since it has higher power irrespective of the sample sizes for both symmetric and asymmetric distribution. In terms of relative efficiency for asymmetric distribution Modified Mann-Whitney U test is more efficient than Mann-Whitney U test (MMWU), and then for symmetric distribution, Mann-Whitney U test (MMWU) is more efficient than Modified Mann-Whitney in sample size of 5;but for other sample sizes considered Modified Mann-Whitney U test (MMWU) is better than Mann-Whitney. Using power of test for both symmetric and asymmetric distributions, Mann-Whitney is more sensitive than Modified Mann-Whitney U test (MMWU) because it has higher power. 展开更多
关键词 ASYMMETRIC SYMMETRIC Nonparametric test Two sample tests Power of test Relative Efficiency
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Research on aiming methods for small sample size shooting tests of two-dimensional trajectory correction fuse
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作者 Chen Liang Qiang Shen +4 位作者 Zilong Deng Hongyun Li Wenyang Pu Lingyun Tian Ziyang Lin 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第3期506-517,共12页
The longitudinal dispersion of the projectile in shooting tests of two-dimensional trajectory corrections fused with fixed canards is extremely large that it sometimes exceeds the correction ability of the correction ... The longitudinal dispersion of the projectile in shooting tests of two-dimensional trajectory corrections fused with fixed canards is extremely large that it sometimes exceeds the correction ability of the correction fuse actuator.The impact point easily deviates from the target,and thus the correction result cannot be readily evaluated.However,the cost of shooting tests is considerably high to conduct many tests for data collection.To address this issue,this study proposes an aiming method for shooting tests based on small sample size.The proposed method uses the Bootstrap method to expand the test data;repeatedly iterates and corrects the position of the simulated theoretical impact points through an improved compatibility test method;and dynamically adjusts the weight of the prior distribution of simulation results based on Kullback-Leibler divergence,which to some extent avoids the real data being"submerged"by the simulation data and achieves the fusion Bayesian estimation of the dispersion center.The experimental results show that when the simulation accuracy is sufficiently high,the proposed method yields a smaller mean-square deviation in estimating the dispersion center and higher shooting accuracy than those of the three comparison methods,which is more conducive to reflecting the effect of the control algorithm and facilitating test personnel to iterate their proposed structures and algorithms.;in addition,this study provides a knowledge base for further comprehensive studies in the future. 展开更多
关键词 Two-dimensional trajectory correction fuse Small sample size test Compatibility test KL divergence Fusion bayesian estimation
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Life prediction and test period optimization research based on small sample reliability test of hydraulic pumps 被引量:5
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作者 郭锐 Ning Chao +4 位作者 Zhao Jingyi Wang Ping Shi Yu Zhou Jinsheng Luo Jing 《High Technology Letters》 EI CAS 2017年第1期63-70,共8页
Hydraulic pumps belong to reliable long-life hydraulic components. The reliability evaluation includes characters such as long test period,high cost,and high power loss and so on. Based on the principle of energy-savi... Hydraulic pumps belong to reliable long-life hydraulic components. The reliability evaluation includes characters such as long test period,high cost,and high power loss and so on. Based on the principle of energy-saving and power recovery,a small sample hydraulic pump reliability test rig is built,and the service life of hydraulic pump is predicted,and then the sampling period of reliability test is optimized. On the basis of considering the performance degradation mechanism of hydraulic pump,the feature information of degradation distribution of hydraulic pump volumetric efficiency during the test is collected,so an optimal degradation path model of feature information is selected from the aspect of fitting accuracy,and pseudo life data are obtained. Then a small sample reliability test of period constrained optimization search strategy for hydraulic pump is constructed to solve the optimization problem of the test sampling period and tightening end threshold,and it is verified that the accuracy of the minimum sampling period by the non-parametric hypothes is tested. Simulation result shows it could possess instructional significance and referenced value for hydraulic pump reliability life evaluation and the test's research and design. 展开更多
关键词 hydraulic pump small sample test volumetric efficiency degradation path model life span period optimal
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Selection of Test Samples for Monitoring Veterinary Drug Residue in Bred Animals
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作者 张兰 潘艳坤 周玉薇 《Agricultural Science & Technology》 CAS 2016年第1期133-135,共3页
[Objective] This study aimed to compare the residue situation of cimaterol,a kind of forbidden veterinary drug in hair, urine and flesh of pig, so as to provide theoretical basis for monitoring veterinary drug residue... [Objective] This study aimed to compare the residue situation of cimaterol,a kind of forbidden veterinary drug in hair, urine and flesh of pig, so as to provide theoretical basis for monitoring veterinary drug residue in bred animals. [Method]Total three different concentrations of cimaterol were administered to pigs, and the residue amounts of cimaterol in pig hair, urine and flesh were monitored at different raising stage. [Result] During the administration period, the residue amount of cimaterol was highest in urine, so urine is the suitable sample for rapid detection of cimaterol in manufacturing enterprises. Cimaterol could be accumulated in pig hair,where cimaterol was metabolized slowly. Thus, pig hair can be used as the test sample for tracing illegal use of veterinary drugs and for vivo detection. Flesh can be used as test sample for direct judgment whether cimaterol residue exceeds the relevant standard. [Conclusion] This study will provide certain theoretical basis for drug monitor in animal husbandry. 展开更多
关键词 Cimaterol Drug residue test sample
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Empirical Analysis of Seasonality Anomalies in Chinese Stock Market Based on Rolling Sample Tests
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作者 Bing Zhang 《Journal of Systems Science and Information》 2006年第3期485-494,共10页
The paper uses rolling sample tests to investigate calendar effect in Chinese stock market, the method is very suitable for emerging market. We utilize GARCH (1,1)- GED model to identify the time varying nature of c... The paper uses rolling sample tests to investigate calendar effect in Chinese stock market, the method is very suitable for emerging market. We utilize GARCH (1,1)- GED model to identify the time varying nature of calendar effect. Friday effect existed with low volatility at the early stage, but it seems to disappear since 1997, and positive Tuesday effect began to appear then. There is small firm January effect with high volatility. 展开更多
关键词 calendar effect rolling sample tests Chinese stock market
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Study on Complete Analysis of LRE Test Samples Based on PCA 被引量:1
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作者 王珉 胡茑庆 《Journal of Measurement Science and Instrumentation》 CAS 2011年第3期217-221,共5页
Incomplete data samples have a serious impact on the effectiveness of data mining.Aiming at the LRE historical test samples,based on correlation analysis of condition parameter,this paper introduced principle componen... Incomplete data samples have a serious impact on the effectiveness of data mining.Aiming at the LRE historical test samples,based on correlation analysis of condition parameter,this paper introduced principle component analysis(PCA)and proposed a complete analysis method based on PCA for incomplete samples.At first,the covariance matrix of complete data set was calculated;Then,according to corresponding eigenvalues which were in descending,a principle matrix composed of eigen-vectors of covariance matrix was made;Finally,the vacant data was estimated based on the principle matrix and the known data.Compared with traditional method validated the method proposed in this paper has a better effect on complete test samples.An application example shows that the method suggested in this paper can update the value in use of historical test data. 展开更多
关键词 test sample data mining correlation analysis PCA complete analysis
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A Cross-cultural Examination of the Noise-sensitivity Scale-short Form:Measurement Invariance Testing between the US and Chinese Samples
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作者 Zachary D Miller HUANG Jun Wu +12 位作者 Heather Costigan LUO Jing DENG Hui Juan XU Xiao Qing B Derrick Taff SUN Cheng YANG Xi WANG Zhong Lei LIN Dan QU Shu Wen PAN Bing LI Guang Ming Peter Newman 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2018年第11期851-854,共4页
Unwanted sound that is unpleasant or disruptive to hear, often interpreted as noise, is a widespread environmental pollutant. Similar to other environmental pollutants, this noise incurs a variety of costs to society.... Unwanted sound that is unpleasant or disruptive to hear, often interpreted as noise, is a widespread environmental pollutant. Similar to other environmental pollutants, this noise incurs a variety of costs to society. Numerous negative health impacts are linked to increases in noise exposure,such as increased cardiovascular risk;and sleep 展开更多
关键词 SF NSS A Cross-cultural Examination of the Noise-sensitivity Scale-short Form:Measurement Invariance testing between the US and Chinese samples CFA TLI CFI US
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A Fault Sample Simulation Approach for Virtual Testability Demonstration Test 被引量:3
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作者 ZHANG Yong QIU Jing +1 位作者 LIU Guanjun YANG Peng 《Chinese Journal of Aeronautics》 SCIE EI CSCD 2012年第4期598-604,共7页
Virtual testability demonstration test has many advantages,such as low cost,high efficiency,low risk and few restrictions.It brings new requirements to the fault sample generation.A fault sample simulation approach fo... Virtual testability demonstration test has many advantages,such as low cost,high efficiency,low risk and few restrictions.It brings new requirements to the fault sample generation.A fault sample simulation approach for virtual testability demonstration test based on stochastic process theory is proposed.First,the similarities and differences of fault sample generation between physical testability demonstration test and virtual testability demonstration test are discussed.Second,it is pointed out that the fault occurrence process subject to perfect repair is renewal process.Third,the interarrival time distribution function of the next fault event is given.Steps and flowcharts of fault sample generation are introduced.The number of faults and their occurrence time are obtained by statistical simulation.Finally,experiments are carried out on a stable tracking platform.Because a variety of types of life distributions and maintenance modes are considered and some assumptions are removed,the sample size and structure of fault sample simulation results are more similar to the actual results and more reasonable.The proposed method can effectively guide the fault injection in virtual testability demonstration test. 展开更多
关键词 fault sample testability demonstration virtual testability test stochastic process statistical simulation Monte Carlo maintenance
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A new discriminative sparse parameter classifier with iterative removal for face recognition
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作者 TANG De-yan ZHOU Si-wang +2 位作者 LUO Meng-ru CHEN Hao-wen TANG Hui 《Journal of Central South University》 SCIE EI CAS CSCD 2022年第4期1226-1238,共13页
Face recognition has been widely used and developed rapidly in recent years.The methods based on sparse representation have made great breakthroughs,and collaborative representation-based classification(CRC)is the typ... Face recognition has been widely used and developed rapidly in recent years.The methods based on sparse representation have made great breakthroughs,and collaborative representation-based classification(CRC)is the typical representative.However,CRC cannot distinguish similar samples well,leading to a wrong classification easily.As an improved method based on CRC,the two-phase test sample sparse representation(TPTSSR)removes the samples that make little contribution to the representation of the testing sample.Nevertheless,only one removal is not sufficient,since some useless samples may still be retained,along with some useful samples maybe being removed randomly.In this work,a novel classifier,called discriminative sparse parameter(DSP)classifier with iterative removal,is proposed for face recognition.The proposed DSP classifier utilizes sparse parameter to measure the representation ability of training samples straight-forward.Moreover,to avoid some useful samples being removed randomly with only one removal,DSP classifier removes most uncorrelated samples gradually with iterations.Extensive experiments on different typical poses,expressions and noisy face datasets are conducted to assess the performance of the proposed DSP classifier.The experimental results demonstrate that DSP classifier achieves a better recognition rate than the well-known SRC,CRC,RRC,RCR,SRMVS,RFSR and TPTSSR classifiers for face recognition in various situations. 展开更多
关键词 collaborative representation-based classification discriminative sparse parameter classifier face recognition iterative removal sparse representation two-phase test sample sparse representation
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Observation of Suicide Prevention in Hospitalized Patients with Depression Based on Taihe Emotion-distress Index
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作者 Jian ZHU 《Medicinal Plant》 CAS 2022年第5期92-93,111,共3页
[Objectives]To reduce suicidal ideation and suicidal behavior through initial screening of patients with suicidal tendencies and implementing suicide prevention interventions during their hospitalization.[Methods]The ... [Objectives]To reduce suicidal ideation and suicidal behavior through initial screening of patients with suicidal tendencies and implementing suicide prevention interventions during their hospitalization.[Methods]The Taihe Emotion-distress Index(THEI)was used to conduct pre-admission and post-discharge tests to explore the effects of suicide prevention measures during hospitalization on the alleviation of the disease and the reduction of suicidal behaviors.The study selected patients who were diagnosed with depression in the psychological outpatient department of Taihe Hospital from April 2019 to September 2019 and had to be hospitalized,including patients with moderate depressive episodes,severe depressive episodes with or without psychotic symptoms,and patients with suicidal thoughts and self-harming behaviors.[Results]The pre-admission and post-discharge test data of hospitalized patients were analyzed,and the non-parametric paired sample T test was carried out,and the result was P<0.05,showing that there are significant differences between the pre-admission and post-discharge test data.[Conclusions]The measures of suicide prevention intervention are effective to a certain extent. 展开更多
关键词 DEPRESSION SUICIDE Taihe Emotion-distress Index(THEI) Non-parametric paired sample T test
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The influence of wave surge force on surf-riding/broaching vulnerability criteria check 被引量:3
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作者 封培元 范佘明 +1 位作者 聂军 刘小健 《Journal of Hydrodynamics》 SCIE EI CSCD 2017年第4期596-602,共7页
This study focuses on the influence of the wave surge force on the assessments of the surf-riding/broaching vulnerability criteria according to the new proposal of the IMO Second Generation Intact Stability Criteria. ... This study focuses on the influence of the wave surge force on the assessments of the surf-riding/broaching vulnerability criteria according to the new proposal of the IMO Second Generation Intact Stability Criteria. A code is developed for the criteria check and the sample ship calculations show that the accuracy of the wave surge force estimation has a significant influence on the assessment result. For further investigation, the wave surge force measurement through a captive model test is made for a purse seiner to validate the numerical model, the effects of the wave steepness and the ship forward speed on the wave surge force responses are also discussed. It is demonstrated that the diffraction effect is important for the correct estimation of the wave surge force. Therefore, it is recommended to include this effect in the assessment procedure. 展开更多
关键词 Intact stability criteria surf-riding/broaching sample calculation wave surge force captive model test
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