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MAXIMUM TEST FOR A SEQUENCE OF QUADRATIC FORM STATISTICS ABOUT SCORE TEST IN LOGISTIC REGRESSION MODEL 被引量:1
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作者 Qing YANG Jiayan ZHU Zhengbang LI 《Acta Mathematica Scientia》 SCIE CSCD 2020年第2期543-556,共14页
This article proposes the maximum test for a sequence of quadratic form statistics about score test in logistic regression model which can be applied to genetic and medicine fields.Theoretical properties about the max... This article proposes the maximum test for a sequence of quadratic form statistics about score test in logistic regression model which can be applied to genetic and medicine fields.Theoretical properties about the maximum test are derived.Extensive simulation studies are conducted to testify powers robustness of the maximum test compared to other two existed test.We also apply the maximum test to a real dataset about multiple gene variables association analysis. 展开更多
关键词 maximum test quadratic form statistics score test asymptotic statistical property
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A New Maximum Test via the Dependent Samples t-Test and the Wilcoxon Signed-Ranks Test 被引量:3
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作者 Saverpierre Maggio Shlomo S. Sawilowsky 《Applied Mathematics》 2014年第1期110-114,共5页
A maximum test in lieu of forcing a choice between the two dependent samples t-test and Wilcoxon signed-ranks test is proposed. The maximum test, which requires a new table of critical values, maintains nominal α whi... A maximum test in lieu of forcing a choice between the two dependent samples t-test and Wilcoxon signed-ranks test is proposed. The maximum test, which requires a new table of critical values, maintains nominal α while guaranteeing the maximum power of the two constituent tests. Critical values, obtained via Monte Carlo methods, are uniformly smaller than the Bonferroni-Dunn adjustment, giving it power superiority when testing for treatment alternatives of shift in location parameter when data are sampled from non-normal distributions. 展开更多
关键词 maximum test DEPENDENT SAMPLES T-test Wilcoxon Signed-Ranks test Bonferroni-Dunn Adjustment Experiment-Wise Type I Error Inferential Statistics Monte Carlo Method
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Analysis of the Maximum Consecutive Precipitation Variation in Liaoning Artificial Precipitation Test Area
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作者 杨旭 高杰 +3 位作者 杨青 田广元 陈刚 胡伟 《Meteorological and Environmental Research》 CAS 2010年第9期46-47,96,共3页
According to the daily precipitation data in artificial precipitation season during May to September from 1961 to 2008 in Liaoning Province,the maximum consecutive precipitation in the artificial precipitation test ar... According to the daily precipitation data in artificial precipitation season during May to September from 1961 to 2008 in Liaoning Province,the maximum consecutive precipitation in the artificial precipitation test area is studied based on the maximum consecutive precipitation from May to September in 48 years.The results shows that the period of maximum consecutive precipitation in each month is different,and the variance trends of maximum consecutive precipitation in May,July,August and September are decreasing,while the variance trend of maximum consecutive precipitation in June is increasing. 展开更多
关键词 Artificial precipitation test area maximum consecutive precipitation Variation analysis China
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Maximum tolerated volume in drinking tests with water and a nutritional beverage for the diagnosis of functional dyspepsia 被引量:3
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作者 Aldo Montao-Loza Max Schmulson +2 位作者 Sergio Zepeda-Gómez Jose Maria Remes-Troche Miguel Angel Valdovinos-Diaz 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第20期3122-3126,共5页
AIM: Recently, drinking load tests with water or nutritional beverages have been proposed as diagnostic tools for functional dyspepsia (FD), therefore we sought to reproduce if these tests can discriminate between FD ... AIM: Recently, drinking load tests with water or nutritional beverages have been proposed as diagnostic tools for functional dyspepsia (FD), therefore we sought to reproduce if these tests can discriminate between FD patients and controls in a Mexican population. METHODS: Twenty FD-Rome Ⅱ patients were matched by age and gender with 20 healthy controls. All underwent both drinking tests at a 15 mL/min rate, randomly, 7 d apart. Every 5 min within each test, four symptoms were evaluated (satiety, bloating, nausea and pain) by Likert scales. Maximum tolerated volume (MTV) was defined as the ingested volume when a score of 5 was reached for any symptom or when the test had to be stopped because the patients could not tolerate more volume. Sensitivity and specificity were analyzed. RESULTS: FD patients had higher symptom scores for both tests compared to controls (water: t= 4.1, P= 0.001 <0.01; Nutren(R): t= 5.2, P= 0.001<0.01). The MTV forwater and Nutren(R) were significantly lower in FD (water: 1014±288 vs 1749±275 mL; t = 7.9, P = 0.001<0.01;Nutren(R): 652±168 vs 1278±286 mL; t= 6.7, P = 0.001<0.01). With the volume tolerated by the controls, the percentile 10 was determined as the lower limit fortolerance. Sensitivity and specificity were 0.90, 0.95 for water and 0.95, 0.95 for Nutren(R) tests.CONCLUSION: A drinking test with water or a nutritional beverage can discriminate between FD patients and healthy subjects in Mexico, with high sensitivity and specificity. These tests could be used as objective, noninvasive, and safe diagnostic approaches for FD patients. 展开更多
关键词 功能性消化不良 诊断方法 饮料 酒精 实验研究
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STUDY ON MAXIMUM SPECIFIC SLUDGE ACTIVITY OF DIFFERENT ANAEROBIC GRANULAR SLUDGE BY BATCH TESTS
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作者 杨虹 K.H.Rosenwinkel H.Meyer 《Journal of Shanghai Jiaotong university(Science)》 EI 2001年第1期67-71,共5页
The maximum specific sludge activity of granular sludge from large scale UASB, IC and Biobed anaerobic reactors were investigated by batch tests. The limitation factors related to maximum specific sludge activity (dif... The maximum specific sludge activity of granular sludge from large scale UASB, IC and Biobed anaerobic reactors were investigated by batch tests. The limitation factors related to maximum specific sludge activity (diffusion, substrate sort, substrate concentration and granular size) were studied. The general principle and procedure for the precise measurement of maximum specific sludge activity were suggested. The potential capacity of loading rate of the IC and Biobed anaerobic reactors were analyzed and compared by use of the batch tests results. 展开更多
关键词 maximum specific sludge activity anaerobic digestion batch test UASB IC Biobed
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Identification of reduced-order model for an aeroelastic system from flutter test data 被引量:5
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作者 Tang Wei Wu Jian Shi Zhongke 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2017年第1期337-347,共11页
Recently, flutter active control using linear parameter varying(LPV) framework has attracted a lot of attention. LPV control synthesis usually generates controllers that are at least of the same order as the aeroela... Recently, flutter active control using linear parameter varying(LPV) framework has attracted a lot of attention. LPV control synthesis usually generates controllers that are at least of the same order as the aeroelastic models. Therefore, the reduced-order model is required by synthesis for avoidance of large computation cost and high-order controller. This paper proposes a new procedure for generation of accurate reduced-order linear time-invariant(LTI) models by using system identification from flutter testing data. The proposed approach is in two steps. The well-known poly-reference least squares complex frequency(p-LSCF) algorithm is firstly employed for modal parameter identification from frequency response measurement. After parameter identification,the dominant physical modes are determined by clear stabilization diagrams and clustering technique. In the second step, with prior knowledge of physical poles, the improved frequencydomain maximum likelihood(ML) estimator is presented for building accurate reduced-order model. Before ML estimation, an improved subspace identification considering the poles constraint is also proposed for initializing the iterative procedure. Finally, the performance of the proposed procedure is validated by real flight flutter test data. 展开更多
关键词 Aeroelastic system Flutter test maximum likelihood Reduced-order model Subspace identification
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Estimation for constant-stress accelerated life test from generalized half-normal distribution 被引量:5
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作者 Liang Wang Yimin Shi 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2017年第4期810-816,共7页
In the constant-stress accelerated life test, estimation issues are discussed for a generalized half-normal distribution under a log-linear life-stress model. The maximum likelihood estimates with the corresponding fi... In the constant-stress accelerated life test, estimation issues are discussed for a generalized half-normal distribution under a log-linear life-stress model. The maximum likelihood estimates with the corresponding fixed point type iterative algorithm for unknown parameters are presented, and the least square estimates of the parameters are also proposed. Meanwhile, confidence intervals of model parameters are constructed by using the asymptotic theory and bootstrap technique. Numerical illustration is given to investigate the performance of our methods. 展开更多
关键词 accelerated life test maximum likelihood estimation least square method bootstrap technique asymptotic distribution
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Determination of the maximum allowable gas pressure for an underground gas storage salt cavern——A case study of Jintan,China 被引量:8
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作者 Tongtao Wang Jianjun Li +3 位作者 Gang Jing Qingqing Zhang Chunhe Yang J.J.K.Daemen 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2019年第2期251-262,共12页
Increasing the allowable gas pressure of underground gas storage(UGS) is one of the most effective methods to increase its working gas capacity. In this context, hydraulic fracturing tests are implemented on the targe... Increasing the allowable gas pressure of underground gas storage(UGS) is one of the most effective methods to increase its working gas capacity. In this context, hydraulic fracturing tests are implemented on the target formation for the UGS construction of Jintan salt caverns, China, in order to obtain the minimum principal in situ stress and the fracture breakdown pressure. Based on the test results, the maximum allowable gas pressure of the Jintan UGS salt cavern is calibrated. To determine the maximum allowable gas pressure, KING-1 and KING-2 caverns are used as examples. A three-dimensional(3D)geomechanical model is established based on the sonar data of the two caverns with respect to the features of the target formation. New criteria for evaluating gas penetration failure and gas seepage are proposed. Results show that the maximum allowable gas pressure of the Jintan UGS salt cavern can be increased from 17 MPa to 18 MPa(i.e. a gradient of about 18 k Pa/m at the casing shoe depth). Based on numerical results, a field test with increasing maximum gas pressure to 18 MPa has been carried out in KING-1 cavern. Microseismic monitoring has been conducted during the test to evaluate the safety of the rock mass around the cavern. Field monitoring data show that KING-1 cavern is safe globally when the maximum gas pressure is increased from 17 MPa to 18 MPa. This shows that the geomechanical model and criteria proposed in this context for evaluating the maximum allowable gas pressure are reliable. 展开更多
关键词 Underground GAS storage(UGS)salt CAVERN In SITU stress testing maximum GAS pressure GAS PENETRATION failure Microseismic monitoring
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Detecting Climate Change Trend, Size, and Change Point Date on Annual Maximum Time Series Rainfall Data for Warri, Nigeria
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作者 Masi G. Sam Ify L. Nwaogazie +2 位作者 Chiedozie Ikebude Chigozie Dimgba Diaa W. El-Hourani 《Open Journal of Modern Hydrology》 2023年第3期165-179,共15页
The study focused on the detection of indicators of climate change in 24-hourly annual maximum series (AMS) rainfall data collected for 36 years (1982-2017) for Warri Township, using different statistical methods yiel... The study focused on the detection of indicators of climate change in 24-hourly annual maximum series (AMS) rainfall data collected for 36 years (1982-2017) for Warri Township, using different statistical methods yielded a statistically insignificant positive mild trend. The IMD and MCIMD downscaled model’s time series data respectively produced MK statistics varying from 1.403 to 1.4729, and 1.403 to 1.463 which were less than the critical Z-value of 1.96. Also, the slope magnitude obtained showed a mild increasing trend in variation from 0.0189 to 0.3713, and 0.0175 to 0.5426, with the rate of change in rainfall intensity at 24 hours duration as 0.4536 and 0.42 mm/hr.year (4.536 and 4.2 mm/decade) for the IMD and the MCIMD time series data, respectively. The trend change point date occurred in the year 2000 from the distribution-free CUSUM test with the trend maintaining a significant and steady increase from 2010 to 2015. Thus, this study established the existence of a trend, which is an indication of a changing climate, and satisfied the condition for rainfall Non-stationary intensity-duration-frequency (NS-IDF) modeling required for infrastructural design for combating flooding events. 展开更多
关键词 Climate Change Annual maximum Series Statistical test Rainfall Trend and Size Change Point Date
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A Problem of Testing Homogeneity Against Order Constraints on Risk Differences
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作者 胡果荣 高巍 史宁中 《Northeastern Mathematical Journal》 CSCD 2004年第2期127-130,共4页
Consider I pairs of independent binomial variates x0i and x1i with corresponding parameters P0i and p1i and sample sizes n0i and n1i for i=1, …,I. Let △i = P1i-P0i be the difference of the two binomial parameters, w... Consider I pairs of independent binomial variates x0i and x1i with corresponding parameters P0i and p1i and sample sizes n0i and n1i for i=1, …,I. Let △i = P1i-P0i be the difference of the two binomial parameters, where △i’s are to be of interest and P0i’s are nuisance parameters. The null hypothesis of homogeneity on the risk difference can be written as 展开更多
关键词 risk difference likelihood ratio test HOMOGENEITY simple order maximum likelihood estimation
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Unified Asymptotic Results for Maximum Spacing and Generalized Spacing Methods for Continuous Models 被引量:1
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作者 Andrew Luong 《Open Journal of Statistics》 2018年第3期614-639,共26页
Asymptotic results are obtained using an approach based on limit theorem results obtained for α-mixing sequences for the class of general spacings (GSP) methods which include the maximum spacings (MSP) method. The MS... Asymptotic results are obtained using an approach based on limit theorem results obtained for α-mixing sequences for the class of general spacings (GSP) methods which include the maximum spacings (MSP) method. The MSP method has been shown to be very useful for estimating parameters for univariate continuous models with a shift at the origin which are often encountered in loss models of actuarial science and extreme models. The MSP estimators have also been shown to be as efficient as maximum likelihood estimators in general and can be used as an alternative method when ML method might have numerical difficulties for some parametric models. Asymptotic properties are presented in a unified way. Robustness results for estimation and parameter testing results which facilitate the applications of the GSP methods are also included and related to quasi-likelihood results. 展开更多
关键词 maximum Product of SPACINGS M-ESTIMATORS QUASI-LIKELIHOOD Ratio test Statistic Α-MIXING Sequences
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Comparative Studyon DC Flashover Characteristics of Iced Insulators with Various Test Methods
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作者 HU Jianlin LUO Mingwu +3 位作者 JIANG Xingliang SUN Caixin ZHANG Zhijin SHU Lichun 《高电压技术》 EI CAS CSCD 北大核心 2012年第8期2051-2058,共8页
关键词 局部放电 射频信号 放电量 高电压技术
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A Fast Bayesian Evaluation Algorithm Based on the Second Category of Maximum Likelihood
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作者 孟晶 郑榕 刘君 《Journal of Donghua University(English Edition)》 EI CAS 2015年第2期305-309,共5页
Directing at evaluation for qualifying rate in weaponry test,this article discusses firstly how field test information is flooded with lots of prior information.Then a fast Bayesian evaluation algorithm is presented b... Directing at evaluation for qualifying rate in weaponry test,this article discusses firstly how field test information is flooded with lots of prior information.Then a fast Bayesian evaluation algorithm is presented based on the elaborate analysis of prior information reliability and the second category of maximum likelihood.The example demonstrates that the algorithm presented in this article is better and more robust compared with classical evaluation algorithm for safe-or-failure test and normal Bayesian method,which can make the best of prior information. 展开更多
关键词 Bayesian prior Likelihood likelihood elaborate conjugate applying calculating confidence consistency
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深水测试管柱内管横向动态特性
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作者 孙巧雷 金雨杰 +2 位作者 刘语维 田杰 冯定 《中国海上油气》 北大核心 2025年第3期244-253,共10页
深水测试管柱的性能直接影响测试系统的安全性。为了掌握深水测试管柱管中管结构中的内管在载荷作用下的横向动态特性,建立了测试管柱管中管三维有限元分析模型,通过搭建管中管力学与流体流动性能测试台架开展实验对比,验证了有限元模... 深水测试管柱的性能直接影响测试系统的安全性。为了掌握深水测试管柱管中管结构中的内管在载荷作用下的横向动态特性,建立了测试管柱管中管三维有限元分析模型,通过搭建管中管力学与流体流动性能测试台架开展实验对比,验证了有限元模型的可靠性;基于该模型进一步分析不同因素对深水测试管柱内管横向振动响应的影响。结果表明:(1)内管壁厚对内管的影响明显,壁厚增加,在各个时刻,内管位移响应减小,且随时间呈周期性变化特征;(2)波浪波高增加在一定程度上增大了波流载荷,内管的位移响应增大但振动周期保持不变;(3)作业水深在1000~1300 m内,不同作业水深工况下,内管30 cm处位移变化的总体趋势基本一致,且随作业水深增加而增大;(4)顶张力有助于增加管柱的整体横向刚度及振动阻尼,增大顶张力,管柱的横向最大变形、位移动力响应均减小。研究为深水测试作业动力学模型的完善以及测试作业的极限工况提供了一定的理论支撑。 展开更多
关键词 深水测试管柱 管中管结构 横向振动 振幅 最大位移
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Asymptotic Results for Goodness-of-Fit Tests Using a Class of Generalized Spacing Methods with Estimated Parameters
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作者 Andrew Luong 《Open Journal of Statistics》 2018年第4期731-746,共16页
A class of pseudo distances is used to derive test statistics using transformed data or spacings for testing goodness-of-fit for parametric models. These statistics can be considered as density based statistics and ex... A class of pseudo distances is used to derive test statistics using transformed data or spacings for testing goodness-of-fit for parametric models. These statistics can be considered as density based statistics and expressible as simple functions of spacings. It is known that when the null hypothesis is simple, the statistics follow asymptotic normal distributions without unknown parameters. In this paper we emphasize results for the null composite hypothesis: the parameters can be estimated by a generalized spacing method (GSP) first which is equivalent to minimize a pseudo distance from the class which is considered;subsequently the estimated parameters are used to replace the parameters in the pseudo distance used for estimation;goodness-of-fit statistics for the composite hypothesis can be constructed and shown to have again an asymptotic normal distribution without unknown parameters. Since these statistics are related to a discrepancy measure, these tests can be shown to be consistent in general. Furthermore, due to the simplicity of these statistics and they come a no extra cost after fitting the model, they can be considered as alternative statistics to chi-square statistics which require a choice of intervals and statistics based on empirical distribution (EDF) using the original data with a complicated null distribution which might depend on the parametric family being considered and also might depend on the vector of true parameters but EDF tests might be more powerful against some specific models which are specified by the alternative hypothesis. 展开更多
关键词 Density Based testS EDF testS Anderson-Darling Statistic Hellinger Distance Statistic PSEUDO-DISTANCE maximum SPACING Method
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某多轴连接双向滑板支座平台设计及安装
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作者 咸庆军 康浩 +2 位作者 贾承辉 张斌 张浩然 《建筑技术开发》 2025年第8期81-84,共4页
某省人民医院为解决新老病房楼的交通连通问题,在新老病房楼之间使用钢结构架空连廊进行连接,架空连廊在新建病房楼一侧采用多轴连接双向滑板支座平台实现弱连接。根据罕遇地震作用下的最大位移和实际承载情况对双向滑板支座进行设计,... 某省人民医院为解决新老病房楼的交通连通问题,在新老病房楼之间使用钢结构架空连廊进行连接,架空连廊在新建病房楼一侧采用多轴连接双向滑板支座平台实现弱连接。根据罕遇地震作用下的最大位移和实际承载情况对双向滑板支座进行设计,通过水平双向最大位移试验验证其满足设计需求。然后介绍双向滑板支座平台的安装过程,并对关键环节进行详细说明,以期为类似工程项目的设计及施工提供参考。 展开更多
关键词 钢结构架空连廊 双向滑板支座 最大位移试验 安装过程
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存储参数对适航用冰雹力学性能的影响
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作者 刘业伟 张丽芬 +1 位作者 葛鑫 刘振侠 《航空动力学报》 北大核心 2025年第3期95-101,共7页
人工冰雹多用于飞行器外壳及发动机测试中,其力学性能对测试结果有直接影响。考虑人工冰雹在制作完成后的存储问题,借助试验研究的方法,探究了存储参数(存储温度、存储时间)对人工冰雹力学性能的影响。在存储温度方面,结果表明在-10、-1... 人工冰雹多用于飞行器外壳及发动机测试中,其力学性能对测试结果有直接影响。考虑人工冰雹在制作完成后的存储问题,借助试验研究的方法,探究了存储参数(存储温度、存储时间)对人工冰雹力学性能的影响。在存储温度方面,结果表明在-10、-15℃和-25℃的3种存储温度下,纯冰冰雹和含棉冰雹的最大抗压强度值均有一定程度的增大,最大增加量分别为73%和80%。在存储时间方面,结果表明在-20℃条件下分别存储5、10 h和20 h后,纯冰冰雹和含棉冰雹的最大抗压强度值均呈现先减小后增大的趋势,并在存储20 h条件下取得最大值,相比未进行存储的冰雹分别增大了113%和54%。因此,存储参数对于冰雹力学性能的影响不可忽视,需在适航测试过程中加以考虑。 展开更多
关键词 人工冰雹 最大抗压强度 适航测试 存储参数 力学性能
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面向智能变电站保护的FMM测试及改进SVM校验诊断技术 被引量:2
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作者 吕鹏飞 裘愉涛 +1 位作者 金盛 王志华 《中国电力》 北大核心 2025年第6期76-82,共7页
为解决智能变电站大量二次设备测试复杂、工期长以及缺乏测试结果诊断的难题,引入正向最大匹配(forward maximum matching,FMM)算法实现保护自动测试,并基于蛙跳算法(frog leaping algorithm,FLA)改进支持向量机(support vector machine... 为解决智能变电站大量二次设备测试复杂、工期长以及缺乏测试结果诊断的难题,引入正向最大匹配(forward maximum matching,FMM)算法实现保护自动测试,并基于蛙跳算法(frog leaping algorithm,FLA)改进支持向量机(support vector machines,SVM)模型完成测试结果的校验诊断。面向智能站保护配置信息关系,提出了保护自动测试与诊断系统架构。通过分析不同保护原理应用电压/电流定值关系建立保护测试需求,构建测试模板集合,利用哈希和编辑距离算法进行相似度比较,基于FMM算法实现了待测装置自动测试。算例分析与工程实例验证了所提技术的有效性。 展开更多
关键词 智能变电站 保护自动测试技术 正向最大匹配算法
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基于物理模型试验的库岸散粒体滑坡涌浪特性
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作者 王珊珊 张检召 +3 位作者 王东坡 杨东旭 袁蔚林 欧阳朝军 《工程科学与技术》 北大核心 2025年第1期107-119,共13页
滑坡涌浪灾害具有历时短、地形条件复杂、规模大的特点,是国内外研究的重要地质和工程问题之一。本文以库岸滑坡失稳入水涌浪过程为研究对象,考虑水上滑坡与淹没滑坡两种情景,设计并开展散粒体滑坡涌浪3维物理模型试验,量测滑坡入水运... 滑坡涌浪灾害具有历时短、地形条件复杂、规模大的特点,是国内外研究的重要地质和工程问题之一。本文以库岸滑坡失稳入水涌浪过程为研究对象,考虑水上滑坡与淹没滑坡两种情景,设计并开展散粒体滑坡涌浪3维物理模型试验,量测滑坡入水运动堆积过程及涌浪产生、传播过程特征,并进一步分析沿滑坡运动方向传播的离岸波与沿河道上下游传播的侧向波波幅、传播规律特性等。结果表明:当滑坡从淹没工况到水上工况时,涌浪波幅最大值特征逐渐从波峰小于波谷转向波峰大于波谷;沿滑坡运动方向产生的涌浪波幅大于沿库岸传播的涌浪波幅,侧向波传播过程中波幅高度衰减程度小于离岸波;进一步分析发现,涌浪沿河道上下游传播时,侧向波最大浪高为其首浪高度的2.5倍;散粒体滑坡涌浪最大高度与散粒体质量成正相关,与散粒体初始淹没率成负相关;受滑坡体入水时相对厚度的影响,涌浪最大高度与入水高差成负相关;在此基础上,利用无量纲分析方法与多元非线性回归方法,推导出散粒体滑坡涌浪最大高度经验公式,并采用提出的经验公式对三峡库区巫山红岩子滑坡与加拿大切哈利斯湖滑坡涌浪案例最大浪高进行计算分析,验证该公式具有较好的适用性和准确性。 展开更多
关键词 滑坡涌浪 散粒体 物理模型试验 传播特性 涌浪最大高度 经验公式
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滚动轴承摩擦力矩时间序列的最大熵分析
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作者 韩一念 陈龙 +2 位作者 张福宇 成依杰 王培龙 《轴承》 北大核心 2025年第7期60-67,共8页
滚动轴承摩擦力矩表现出不确定的波动与趋势变化,属于概率分布和趋势规律均未知的乏信息系统。为了对轴承摩擦力矩时间序列进行动态预报,提出了一种基于最大熵原理的轴承摩擦力矩性能序列动态预报模型。对摩擦力矩原始数据分组,将完整... 滚动轴承摩擦力矩表现出不确定的波动与趋势变化,属于概率分布和趋势规律均未知的乏信息系统。为了对轴承摩擦力矩时间序列进行动态预报,提出了一种基于最大熵原理的轴承摩擦力矩性能序列动态预报模型。对摩擦力矩原始数据分组,将完整的时间序列划分为多个子时间序列,当子序列中包含轴承性能退化的数据时,继续划分映射参数最早发生变化的子序列,比较划分后的子序列映射参数变化与轴承性能失效的时间顺序,以实现轴承性能失效预报。研究结果表明:映射参数与概率密度函数图像变化具有一致性,引入映射参数作为最佳特征参数表征轴承性能演变,A,B轴承可分别提前120,80 min预报轴承失效;该摩擦力矩时间序列动态预报模型可有效应用于工程实际中的轴承健康监测与安全诊断。 展开更多
关键词 滚动轴承 摩擦力矩 时间序列 最大熵原理 耐久性试验 概率密度函数
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