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老旧电梯安全评估方法及主要部件风险分析
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作者 谢建雄 陈奕波 《中国电梯》 2024年第2期73-75,共3页
老旧电梯安全隐患日益增多,对老旧电梯进行安全性风险评估十分必要。介绍了根据适用情况和使用场景,可进行选择的3种老旧电梯安全性风险评估方法—风险值评估法、层次分析法、故障树分析评估法。还介绍了老旧电梯主要部件常见问题及风... 老旧电梯安全隐患日益增多,对老旧电梯进行安全性风险评估十分必要。介绍了根据适用情况和使用场景,可进行选择的3种老旧电梯安全性风险评估方法—风险值评估法、层次分析法、故障树分析评估法。还介绍了老旧电梯主要部件常见问题及风险分析,总结了电梯主要部件报废技术条件,为提高老旧电梯的使用安全性和管理科学性提供了参考。 展开更多
关键词 老旧电梯 安全性风险评估方法 主要部件风险分析 主要部件报废技术条件
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Feature extraction of wood-hole defects using wavelet-based ultrasonic testing 被引量:7
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作者 Huiming Yang Lei Yu 《Journal of Forestry Research》 SCIE CAS CSCD 2017年第2期395-402,共8页
The primary bottleneck to extracting wood defects during ultrasonic testing is the accuracy of identifying the wood defects. The wavelet energy moment was used to extract defect features of artificial wood holes drill... The primary bottleneck to extracting wood defects during ultrasonic testing is the accuracy of identifying the wood defects. The wavelet energy moment was used to extract defect features of artificial wood holes drilled into 120 elm samples that differed in the number of holes to verify the validity of the method. Wavelet energy moment can reflect the distribution of energy along the time axis and the amount of energy in each frequency band,which can effectively extract the energy distribution characteristics of signals in each frequency band; therefore,wavelet energy moment can replace the wavelet frequency band energy and constitute wood defect feature vectors. A principal component analysis was used to normalize and reduce the dimension of the feature vectors. A total of 16 principal component features were then obtained, which can effectively extract the defect features of the different number of holes in the elm samples. 展开更多
关键词 伍德 表演抽取 小浪精力时刻 主要部件分析
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Influence of light intensity and water content of medium on total dendrobine of Dendrobium nobile Lindl 被引量:7
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作者 Jin-Ling Li Zhi Zhao +2 位作者 Hong-Chang Liu Chun-Li Luo Hua-Lei Wang 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2017年第11期1095-1100,共6页
Objective: To ascertain the influence of light intensity and water content of medium on the total dendrobine of Dendrobium nobile(D. nobile).Method: The principal component analysis combined with total dendrobine accu... Objective: To ascertain the influence of light intensity and water content of medium on the total dendrobine of Dendrobium nobile(D. nobile).Method: The principal component analysis combined with total dendrobine accumulation was conducted to assess the yield and quality of D. nobile in all treatments. In the experiment, D. nobile plants were cultivated in greenhouse as tested materials, and complete test of 9 treatments was adopted with relative light intensities 75.02%, 39.74%,29.93% and relative water content of medium 50%, 65%, 80%. The plants were treated in June and harvested till December. Indexes including agronomic traits, fresh weight and dry weight of stem and leaf, ash content, extract, and dendrobine were measured.Results: Under the light intensity treatments of 75.02% with 50%, 65%, 80% water content of medium, the basal stems of plants were comparatively thicker with more leaves, and the fresh weight and dry weight of stems and leaves were significantly higher than other 6 treatments.Leaves in all treatments contained dendrobine. Under the light intensity treatments of 75.02%with 50%, 65%, 80% water content of medium, dendrobine content of leaves was lower while dendrobine contents of other treatments were more than 0.60%. After comprehensive assessment through the principal component analysis and total dendrobine accumulation, the results showed that 3 treatments with relative light intensity of 75.02% ranked the top three.Conclusions: In brief, the moderately strong light intensity and water content of medium from low to medium can facilitate the growth and yield of D. nobile plants, while light intensity from moderately weak to weak can enhance the dendrobine content. 展开更多
关键词 Dendrobium nobile 轻紧张 浇媒介的内容 全部的 dendrobine 主要部件分析
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Evaluation and Selection of Sealants and Fillers Using Principal Component Analysis for Cracks in Asphalt Concrete Pavements 被引量:7
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作者 李波 REN Xiaoyu +2 位作者 LI Yanbo MA Weizhong LI Hanlian 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2017年第2期408-412,共5页
The objective of this paper was to develop a comprehensive evaluation method and index to evaluate the performance of sealants and fillers for cracks in asphalt concrete pavements using the method of principal compone... The objective of this paper was to develop a comprehensive evaluation method and index to evaluate the performance of sealants and fillers for cracks in asphalt concrete pavements using the method of principal component analysis. The performance experiments including cone penetration, softening point, flow, resilience and tension at low temperature respectively were conducted by reference of ASTM D5329 for eight sealants and fillers often used in China. There by a principal component model was developed and weight of every index was calculated. The experimental results show that there are significantly different performances for sealants and fillers often used in China. Principal component analysis is an objective method that evaluates and selects the performance of sealants and fillers for cracks in asphalt concrete pavements. 展开更多
关键词 道路材料 沥青人行道 密封剂和 fillers 主要部件分析 全面评估
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On arable land changes in Shandong Province and their driving forces 被引量:5
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作者 SHAO Xiao-mei, ZHANG Hong-ye (Institute of Geographic Sciences and Natural Resources Research, CAS, Beijing 100101, China) 《Journal of Geographical Sciences》 SCIE CSCD 2001年第3期329-335,共7页
The decrease of total cultivated area and the lower per capita available arable land resource are now serious problems in Shandong Province, a major agricultural province in China. These problems will become more seri... The decrease of total cultivated area and the lower per capita available arable land resource are now serious problems in Shandong Province, a major agricultural province in China. These problems will become more serious along with the further development of economy. In this paper, based on the statistical information at provincial and county levels, the changes of arable land in Shandong Province and their driving forces during the last 50 years are analyzed. The general changing trends of arable land and per capita available arable land are reducing, and the trends of decrease will continue when the economy is developing. The result of GIS spatial analysis shows that the change of the arable land use in Shandong Province has a regional difference. Eight variables having influences on cultivated land change are analyzed by principal component analysis. The results show that the dynamic development of economy, pressure of social system and progress of scientific techniques in agriculture are the main causes for cultivated land reduction. The principal factors which can be considered as driving forces for arable land change include per capita net living space, total population and per ha grain yield. By using regressive equation, along with analysis on population growth and economic development, cultivated areas in Shandong Province in 2005 and 2010 are predicted respectively. The predicted cultivated areas in Shandong will be 6435.47 thousand ha in 2005 and 6336.23 thousand ha in 2010 respectively. 展开更多
关键词 可耕地 动态变化 驱动力 主要部件分析 山东省
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Watermarking Based on Principal Component Analysis 被引量:10
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作者 WANG Shuo zhong School of Communication and Information Engineering, Shanghai University, Shanghai 200072, China 《Advances in Manufacturing》 2000年第1期22-26,共5页
A new watermarking scheme using principal component analysis (PCA) is described.The proposed method inserts highly robust watermarks into still images without degrading their visual quality. Experimental results are p... A new watermarking scheme using principal component analysis (PCA) is described.The proposed method inserts highly robust watermarks into still images without degrading their visual quality. Experimental results are presented, showing that the PCA based watermarks can resist malicious attacks including lowpass filtering, re scaling, and compression coding. 展开更多
关键词 WATERMARKING 主要部件分析(PCA ) Karhunen-Loeve 变换(KLT )
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Hydrochemical characteristics of salt marsh wetlands in western Songnen Plain 被引量:2
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作者 DENG Wei~1, HE Yan~2, SONG Xin-shan~1, YAN Bai-xing~1 (1. Changchun Institute of Geography, CAS, Changchun 130021, China 2. Chinese Academy of Sciences, Beijing 100864, China) 《Journal of Geographical Sciences》 SCIE CSCD 2001年第2期217-223,共7页
In western Songnen Plain of China, the saline-alkaline degree of water bodies is high in salt marsh wetlands. Generally, pH is above 8.0, and the hydrochemical types belong to HCO32--Na+. Through analysis on the basic... In western Songnen Plain of China, the saline-alkaline degree of water bodies is high in salt marsh wetlands. Generally, pH is above 8.0, and the hydrochemical types belong to HCO32--Na+. Through analysis on the basic saline variables such as CO32-, HCO32-, Cl-, Ca2+, Mg2+, SO42-, Na+, and the derivative variables such as SAR, SDR, RSC, SSP, the relationships between different variables are found, and the discriminant equations are established to identify different saline-alkaline water bodies by using principal component analysis. 展开更多
关键词 盐沼沼泽地 hydrochemical 打字 关联分析 主要部件分析 判别式分析 Songnen 平原
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Fault detection method with PCA and LDA and its application to induction motor 被引量:3
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作者 JUNG D Y LEE S M +2 位作者 王洪梅 KIM J H LEE S H 《Journal of Central South University》 SCIE EI CAS 2010年第6期1238-1242,共5页
A feature extraction and fusion algorithm was constructed by combining principal component analysis(PCA) and linear discriminant analysis(LDA) to detect a fault state of the induction motor.After yielding a feature ve... A feature extraction and fusion algorithm was constructed by combining principal component analysis(PCA) and linear discriminant analysis(LDA) to detect a fault state of the induction motor.After yielding a feature vector with PCA and LDA from current signal that was measured by an experiment,the reference data were used to produce matching values.In a diagnostic step,two matching values that were obtained by PCA and LDA,respectively,were combined by probability model,and a faulted signal was finally diagnosed.As the proposed diagnosis algorithm brings only merits of PCA and LDA into relief,it shows excellent performance under the noisy environment.The simulation was executed under various noisy conditions in order to demonstrate the suitability of the proposed algorithm and showed more excellent performance than the case just using conventional PCA or LDA. 展开更多
关键词 主要部件分析(PCA ) 线性判别式分析(LDA ) 正式就职马达差错诊断熔化算法
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Sensors Array Technique for Monitoring Aluminum Alloy Spot Welding
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作者 王蕤 罗震 +3 位作者 单平 步贤政 袁书现 敖三三 《Transactions of Tianjin University》 EI CAS 2010年第5期322-327,共6页
In this paper,the sensors array technique is applied to the quality detection of aluminum alloy spot welding.The sensors array has three forms,i.e.,linear magnetic sensors array,annular magnetic sensors array and cros... In this paper,the sensors array technique is applied to the quality detection of aluminum alloy spot welding.The sensors array has three forms,i.e.,linear magnetic sensors array,annular magnetic sensors array and cross magnetic sensors array.An algorithm based on principal component analysis is proposed to extract the signal eigenvalues.The three types of magnetic sensors array are used in the experiment of monitoring the signal.After the eigenvalues are extracted,they are used to build a relationship with the nugget information.The result shows that when the distance between the core of the array and the pole is 60 mm,the arrays work best.In this case,when the eigenvalues' range of the linear array is 0.006 5-0.015 1,the quality of the spots is eligible.To the annular and cross array,when the ranges are 0.082 9-0.131 6 and 0.085 1-0.098 2 respectively,the nugget quality is eligible. 展开更多
关键词 点焊 磁场 传感器数组 主要部件分析
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Time Series of EIT Measurements and Images During Lung Ventilation Based on Principal Component Analysis
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作者 范文茹 王化祥 +1 位作者 杨程屹 马世文 《Transactions of Tianjin University》 EI CAS 2010年第5期366-372,共7页
The aim of this paper is to propose a useful method for exploring regional ventilation and perfusion in the chest and also separation of pulmonary and cardiac changes.The approach is based on estimating both electrica... The aim of this paper is to propose a useful method for exploring regional ventilation and perfusion in the chest and also separation of pulmonary and cardiac changes.The approach is based on estimating both electrical impedance tomography(EIT) measurements and reconstructed images by means of principal component analysis(PCA).In the experiments in vivo,43 cycles of heart-beat rhythm could be detected by PCA when the volunteer held breath;9 breathing cycles and 50 heart-beat cycles could be detected by PCA when the volunteer breathed normally.The results indicate that the rhythms of cardiac activity and respiratory process can be exploited and separated through analyzing the boundary measurements by PCA without image reconstruction. 展开更多
关键词 电的阻抗断层摄影术 图象重建 主要部件分析
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A Novel Intrusion Detection Method Based on Improved SVM by Combining PCA and PSO 被引量:5
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作者 WANG Hui ZHANG Guilingi +1 位作者 E Mingjie SUN Na 《Wuhan University Journal of Natural Sciences》 CAS 2011年第5期409-413,共5页
The paper presents an improved support vector machine (SVM) by combining principal component analysis (PCA) and particle swarm optimization (PSO).Then,the improved SVM is applied to the intrusion detection system (IDS... The paper presents an improved support vector machine (SVM) by combining principal component analysis (PCA) and particle swarm optimization (PSO).Then,the improved SVM is applied to the intrusion detection system (IDS) to improve the detection rate.First,PCA is used to reduce the dimension of feature vectors.Second,we use the PSO algorithm to optimize the punishment factor C and kernel parameters in SVM.The experimental results indicate that the intrusion detection rate (97.752 8%) of improved SVM by combining PCA and PSO is higher than those (95.635 5%) of PSO-SVM and those (90.476 2%) of standard SVM with KDD Cup 1999 data set. 展开更多
关键词 侵入察觉 支持向量机器 主要部件分析 粒子群优化
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Investigation on color variation of Morpho butterfly wings hierarchical structure based on PCA 被引量:2
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作者 JIANG Xuan SHI TieLin +3 位作者 ZUO HaiBo YANG XueFeng WU WenJun LIAO GuangLan 《Science China(Technological Sciences)》 SCIE EI CAS 2012年第1期16-21,共6页
Morpho butterfly wings show brilliant blue color,which has a close relationship with the hierarchical micro/nano structures on the surface of scales.When liquids such as methanol,ethanol and isopropanol with different... Morpho butterfly wings show brilliant blue color,which has a close relationship with the hierarchical micro/nano structures on the surface of scales.When liquids such as methanol,ethanol and isopropanol with different refractive indexes drop onto the scales,the reflectance of wings would decrease.The main peaks of reflectance shift to the right and the scales turn to yel-low-green.After the liquids volatilizes completely,the scales revert to the original blue color.The typical micro/nano struc-tures of Morpho butterfly wing scales are modeled,and the reflectance variation in the course of dropping liquids is simulated.Furthermore,the principal component analysis(PCA) method is employed to analyze the experimental and simulation reflec-tance data,extract principal components and reduce dimensions.As a result,the curves mapping the reflectance variation are clearly shown in the coordinate system consisting of three principal components.The typical color variation of scales during the dropping process could be monitored,and different kinds of liquids could be obviously distinguished according to the dis-tributed regions of mapping points.This study provides guidance to environmental media detecting as well as data processing,and enhances the fabrication and application of the mimic Morpho butterfly wings micro/nano structures. 展开更多
关键词 Morpho 蝴蝶 层次结构 颜色变化 主要部件分析
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Multivariate error assessment of response time histories method for dynamic systems 被引量:1
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作者 Zhen-fei ZHAN Jie HU +3 位作者 Yan FU Ren-Jye YANG Ying-hong PENG Jin QI 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2012年第2期121-131,共11页
In this paper, an integrated validation method and process are developed for multivariate dynamic systems. The principal component analysis approach is used to address multivariate correlation and dimensionality reduc... In this paper, an integrated validation method and process are developed for multivariate dynamic systems. The principal component analysis approach is used to address multivariate correlation and dimensionality reduction, the dynamic time warping and correlation coefficient are used for error assessment, and the subject matter experts (SMEs)’ opinions and principal component analysis coefficients are incorporated to provide the overall rating of the dynamic system. The proposed method and process are successfully demonstrated through a vehicle dynamic system problem. 展开更多
关键词 模型确认 Multivariate 动态回答 主要部件分析 动态时间变弯
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Puma (Puma concolor) epididymal sperm morphometry
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作者 Hernan Cucho Virgilio Alarcon +3 位作者 Cesar Ordonez Enrique Ampuero Aydee Meza Caries Solere 《Asian Journal of Andrology》 SCIE CAS CSCD 2016年第6期879-881,共3页
Andes 山脉的美洲狮(美洲狮 concolor ) 广泛地没被学习,特别地在它的精液特征的参考。现在的学习的目的是定义美洲狮精子头的 morphometry 并且由簇分析分类他们的 subpopulations。样品从一个动物从二 epididymides 验尸被恢复并且在... Andes 山脉的美洲狮(美洲狮 concolor ) 广泛地没被学习,特别地在它的精液特征的参考。现在的学习的目的是定义美洲狮精子头的 morphometry 并且由簇分析分类他们的 subpopulations。样品从一个动物从二 epididymides 验尸被恢复并且在与 Hemacolor 工具包染色以后为词法观察准备了。Morphometric 数据用一个 CASA-Morph 系统从 581 精子被获得,显示 13 个 morphometric 参数。主要部件(PC ) 分析被执行为 subpopulations 的建立由簇分析列在后面。二个 PC 部件被获得,第一与尺寸有关并且第二塑造。三 subpopulations 被观察,相应于伸长并且中间尺寸的精子头和 acrosomes 到有大 acrosomes 的大头,并且到有短 acrosomes 的小头。在结论,美洲狮精子没显示出一致精子形态学但是三清楚的 subpopulations。这些结果应该在这种的一个足够的 germplasm 银行的建立被用于未来工作。 展开更多
关键词 主要部件分析 美洲狮 精子 morphometry SUBPOPULATION 野生的动物
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Sperm subpopulations in avian species: a comparative study between the rooster (Gallus domesticus) and Guinea fowl (Numida meleagris)
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作者 Manuel Garcia-Herreros 《Asian Journal of Andrology》 SCIE CAS CSCD 2016年第6期889-894,共6页
这研究的主要目的是在客观 morphometric 精子特征学习可能的差别,建立标准精子 morphometry 标准,并且评估从公鸡(吊裤带 domesticus ) 和象模型的畿尼家禽(Numida meleagris ) 的鸟的精子的假定不同 subpopulation 分发鸟的种类。72... 这研究的主要目的是在客观 morphometric 精子特征学习可能的差别,建立标准精子 morphometry 标准,并且评估从公鸡(吊裤带 domesticus ) 和象模型的畿尼家禽(Numida meleagris ) 的鸟的精子的假定不同 subpopulation 分发鸟的种类。72 精液(36 每种类学习了) 手工地被获得,跟随轻轻地包含的一个训练时期联合了鸟的 dorso 腹、 lumbo 骶的按摩。精液为体积,精子集中,生存能力,活动性,和形态学被处理。而且,样品为 Morphometry (CASA-Morph ) 方法用客观帮助计算机的精液分析为精子 morphometric 评价被提交,与精子 morphometric,描述符由主要部件分析(PCA ) 和 multivariate 聚类分析评估了。有几差别,在为精液体积和精子集中获得的价值在鸟的种类之间观察(P &#x0003c;0.001 ) 。不管种类, PCA 揭示了解释超过 80% 变化的二个主要部件(PC ) 。另外, subpopulations 的数字与种类不同(为公鸡和畿尼家禽的三和五 subpopulations,分别地) 。而且,精子 subpopulations 的分发在种类之间被发现是在结构上不同。在结论,我们从使用方法显示的 CASA-Morph 的调查结果读了在这之间的精子 morphometric 变化二鸟的种。因为在 morphometric 参数值和他们的 subpopulation 分发观察的强壮的差别,这些结果建议象 CASA-Morph 那样的客观分析方法的申请能实质地改进比较研究的可靠性并且帮助建立有效标准精子为鸟的种类的词法值。 展开更多
关键词 吊裤带 domesticus Numida meleagris 主要部件分析 精子 morphometry 精子 subpopulations
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Study on Diagnosis Criteria of Fire-Heat Syndrome Based on Receiver Operating Characteristic Curve and Principal Component Analysis
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作者 刘四军 黄兆胜 +7 位作者 吴庆光 黄张杰 吴丽蓉 闫文丽 王奇 王宗伟 张伦博 杨政 《Chinese Journal of Integrative Medicine》 SCIE CAS CSCD 2016年第4期258-266,共9页
Objective: To establish the diagnostic quantitative criteria for fire-heat syndrome(FHS) of Chinese medicine(CM) based on the receiver operating characteristic(ROC) curve and principal component analysis(PCA). Methods... Objective: To establish the diagnostic quantitative criteria for fire-heat syndrome(FHS) of Chinese medicine(CM) based on the receiver operating characteristic(ROC) curve and principal component analysis(PCA). Methods: The symptoms and signs of FHS cases and healthy subjects from Guangzhou, Henan and Hunan of China were collected through questionnaire, and the diagnostic quantitative score tables were established for the three regions, respectively, with the method of maximum likelihood analysis. The homogeneity test was then performed on the diagnostic score tables for the three regions with ROC curve, and the diagnostic efficiency of diagnostic score tables for the three regions was compared with the prospective test and retrospective test. The method of PCA was adopted to obtain the analysis matrix for classifying the tapes of FHS. Results: Twenty-seven elements of FHS were confirmed through Chi-square test, and the diagnostic score tables for the three regions were established with the method of maximum likelihood analysis on the basis of the collected case data. According to the ROC curve test, the areas under ROC curve of Guangzhou diagnostic score table assessment with candidates in Guangzhou, Henan and Hunan were 0.998, 0.961 and 0.956, respectively. It showed that the diagnostic efficiency of Guangzhou diagnostic score tables was the highest one. With the prospective test, the area under ROC of Guangzhou diagnostic score table was 0.949, and more than any other diagnostic score table. By PCA, FHS was classified into excess fire and deficiency fire, and then classified into syndrome of flaring up of Heart(Xin) fire, syndrome of Lung(Fei)-Stomach(Wei) excess fire, syndrome of deficiency of Liver(Gan)-yin and Kidney(Shen)-yin, and syndrome of deficiency of Lung-yin from the view of viscera. In the retrospective test, the consistency with clinicians' diagnosis was 69.4%, and in the prospective test, it was 70.1%. Conclusions: The Guangzhou diagnostic score table could be used as the recommended criteria for the diagnosis of FHS. The classification of FHS was basically in conformity with the clinical situation. 展开更多
关键词 操作典型曲线的接收装置 主要部件分析 诊断标准 火热症候群 中国药
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