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Estimation of the Number of Collapsed Houses Damaged by Typhoon Based on Principal Components Analysis and Support Vector Machine 被引量:2
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作者 张新厂 娄伟平 《Meteorological and Environmental Research》 CAS 2010年第4期11-14,共4页
The evaluation model was established to estimate the number of houses collapsed during typhoon disaster for Zhejiang Province.The factor leading to disaster,the environment fostering disaster and the exposure of build... The evaluation model was established to estimate the number of houses collapsed during typhoon disaster for Zhejiang Province.The factor leading to disaster,the environment fostering disaster and the exposure of buildings were processed by Principal Component Analysis.The key factor was extracted to support input of vector machine model and to build an evaluation model;the historical fitting result kept in line with the fact.In the real evaluation of two typhoons landed in Zhejiang Province in 2008 and 2009,the coincidence of evaluating result and actual value proved the feasibility of this model. 展开更多
关键词 TYPHOON The number of collapsed houses principal Components Analysis Support vector Machine EVALUATION China
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Laser-induced breakdown spectroscopy applied to the characterization of rock by support vector machine combined with principal component analysis 被引量:6
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作者 杨洪星 付洪波 +3 位作者 王华东 贾军伟 Markus W Sigrist 董凤忠 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第6期290-295,共6页
Laser-induced breakdown spectroscopy(LIBS) is a versatile tool for both qualitative and quantitative analysis.In this paper,LIBS combined with principal component analysis(PCA) and support vector machine(SVM) is... Laser-induced breakdown spectroscopy(LIBS) is a versatile tool for both qualitative and quantitative analysis.In this paper,LIBS combined with principal component analysis(PCA) and support vector machine(SVM) is applied to rock analysis.Fourteen emission lines including Fe,Mg,Ca,Al,Si,and Ti are selected as analysis lines.A good accuracy(91.38% for the real rock) is achieved by using SVM to analyze the spectroscopic peak area data which are processed by PCA.It can not only reduce the noise and dimensionality which contributes to improving the efficiency of the program,but also solve the problem of linear inseparability by combining PCA and SVM.By this method,the ability of LIBS to classify rock is validated. 展开更多
关键词 laser-induced breakdown spectroscopy(LIBS) principal component analysis(PCA) support vector machine(SVM) lithology identification
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Support vector classifier based on principal component analysis 被引量:1
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作者 Zheng Chunhong Jiao Licheng Li Yongzhao 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2008年第1期184-190,共7页
Support vector classifier (SVC) has the superior advantages for small sample learning problems with high dimensions, with especially better generalization ability. However there is some redundancy among the high dim... Support vector classifier (SVC) has the superior advantages for small sample learning problems with high dimensions, with especially better generalization ability. However there is some redundancy among the high dimensions of the original samples and the main features of the samples may be picked up first to improve the performance of SVC. A principal component analysis (PCA) is employed to reduce the feature dimensions of the original samples and the pre-selected main features efficiently, and an SVC is constructed in the selected feature space to improve the learning speed and identification rate of SVC. Furthermore, a heuristic genetic algorithm-based automatic model selection is proposed to determine the hyperparameters of SVC to evaluate the performance of the learning machines. Experiments performed on the Heart and Adult benchmark data sets demonstrate that the proposed PCA-based SVC not only reduces the test time drastically, but also improves the identify rates effectively. 展开更多
关键词 support vector classifier principal component analysis feature selection genetic algorithms
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Anomaly Detection System Based on Principal Component Analysis and Support Vector Machine 被引量:1
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作者 LI Zhanchun LI Zhitang LIU Bin 《Wuhan University Journal of Natural Sciences》 CAS 2006年第6期1769-1772,共4页
This article presents an anomaly detection system based on principal component analysis (PCA) and support vector machine (SVM). The system first creates a profile defining a normal behavior by frequency-based sche... This article presents an anomaly detection system based on principal component analysis (PCA) and support vector machine (SVM). The system first creates a profile defining a normal behavior by frequency-based scheme, and then compares the similarity of a current behavior with the created profile to decide whether the input instance is norreal or anomaly. In order to avoid overfitting and reduce the computational burden, normal behavior principal features are extracted by the PCA method. SVM is used to distinguish normal or anomaly for user behavior after training procedure has been completed by learning. In the experiments for performance evaluation the system achieved a correct detection rate equal to 92.2% and a false detection rate equal to 2.8%. 展开更多
关键词 anomaly detection principal component analysis (PCA) support vector machine (SVM)
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Combination Method of Principal Component Analysis and Support Vector Machine for On-line Process Monitoring and Fault Diagnosis 被引量:2
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作者 赵旭 文香军 邵惠鹤 《Journal of Donghua University(English Edition)》 EI CAS 2006年第1期53-58,共6页
On-line monitoring and fault diagnosis of chemical process is extremely important for operation safety and product quality. Principal component analysis (PCA) has been widely used in multivariate statistical process m... On-line monitoring and fault diagnosis of chemical process is extremely important for operation safety and product quality. Principal component analysis (PCA) has been widely used in multivariate statistical process monitoring for its ability to reduce processes dimensions. PCA and other statistical techniques, however, have difficulties in differentiating faults correctly in complex chemical process. Support vector machine (SVM) is a novel approach based on statistical learning theory, which has emerged for feature identification and classification. In this paper, an integrated method is applied for process monitoring and fault diagnosis, which combines PCA for fault feature extraction and multiple SVMs for identification of different fault sources. This approach is verified and illustrated on the Tennessee Eastman benchmark process as a case study. Results show that the proposed PCA-SVMs method has good diagnosis capability and overall diagnosis correctness rate. 展开更多
关键词 principal component analysis multiple support vector machine process monitoring fault detection fault diagnosis.
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Predicting configuration performance of modular product family using principal component analysis and support vector machine 被引量:1
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作者 张萌 李国喜 +1 位作者 龚京忠 吴宝中 《Journal of Central South University》 SCIE EI CAS 2014年第7期2701-2711,共11页
A novel configuration performance prediction approach with combination of principal component analysis(PCA) and support vector machine(SVM) was proposed.This method can estimate the performance parameter values of a n... A novel configuration performance prediction approach with combination of principal component analysis(PCA) and support vector machine(SVM) was proposed.This method can estimate the performance parameter values of a newly configured product through soft computing technique instead of practical test experiments,which helps to evaluate whether or not the product variant can satisfy the customers' individual requirements.The PCA technique was used to reduce and orthogonalize the module parameters that affect the product performance.Then,these extracted features were used as new input variables in SVM model to mine knowledge from the limited existing product data.The performance values of a newly configured product can be predicted by means of the trained SVM models.This PCA-SVM method can ensure that the performance prediction is executed rapidly and accurately,even under the small sample conditions.The applicability of the proposed method was verified on a family of plate electrostatic precipitators. 展开更多
关键词 design configuration performance prediction MODULARITY principal component analysis support vector machine
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Lung Cancer Prediction from Elvira Biomedical Dataset Using Ensemble Classifier with Principal Component Analysis
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作者 Teresa Kwamboka Abuya 《Journal of Data Analysis and Information Processing》 2023年第2期175-199,共25页
Machine learning algorithms (MLs) can potentially improve disease diagnostics, leading to early detection and treatment of these diseases. As a malignant tumor whose primary focus is located in the bronchial mucosal e... Machine learning algorithms (MLs) can potentially improve disease diagnostics, leading to early detection and treatment of these diseases. As a malignant tumor whose primary focus is located in the bronchial mucosal epithelium, lung cancer has the highest mortality and morbidity among cancer types, threatening health and life of patients suffering from the disease. Machine learning algorithms such as Random Forest (RF), Support Vector Machine (SVM), K-Nearest Neighbor (KNN) and Naïve Bayes (NB) have been used for lung cancer prediction. However they still face challenges such as high dimensionality of the feature space, over-fitting, high computational complexity, noise and missing data, low accuracies, low precision and high error rates. Ensemble learning, which combines classifiers, may be helpful to boost prediction on new data. However, current ensemble ML techniques rarely consider comprehensive evaluation metrics to evaluate the performance of individual classifiers. The main purpose of this study was to develop an ensemble classifier that improves lung cancer prediction. An ensemble machine learning algorithm is developed based on RF, SVM, NB, and KNN. Feature selection is done based on Principal Component Analysis (PCA) and Analysis of Variance (ANOVA). This algorithm is then executed on lung cancer data and evaluated using execution time, true positives (TP), true negatives (TN), false positives (FP), false negatives (FN), false positive rate (FPR), recall (R), precision (P) and F-measure (FM). Experimental results show that the proposed ensemble classifier has the best classification of 0.9825% with the lowest error rate of 0.0193. This is followed by SVM in which the probability of having the best classification is 0.9652% at an error rate of 0.0206. On the other hand, NB had the worst performance of 0.8475% classification at 0.0738 error rate. 展开更多
关键词 ACCURACY False Positive Rate Naïve Bayes Random Forest Lung Cancer Prediction principal Component Analysis Support vector Machine K-Nearest Neighbor
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Comparison of debris flow susceptibility assessment methods:support vector machine,particle swarm optimization,and feature selection techniques
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作者 ZHAO Haijun WEI Aihua +3 位作者 MA Fengshan DAI Fenggang JIANG Yongbing LI Hui 《Journal of Mountain Science》 SCIE CSCD 2024年第2期397-412,共16页
The selection of important factors in machine learning-based susceptibility assessments is crucial to obtain reliable susceptibility results.In this study,metaheuristic optimization and feature selection techniques we... The selection of important factors in machine learning-based susceptibility assessments is crucial to obtain reliable susceptibility results.In this study,metaheuristic optimization and feature selection techniques were applied to identify the most important input parameters for mapping debris flow susceptibility in the southern mountain area of Chengde City in Hebei Province,China,by using machine learning algorithms.In total,133 historical debris flow records and 16 related factors were selected.The support vector machine(SVM)was first used as the base classifier,and then a hybrid model was introduced by a two-step process.First,the particle swarm optimization(PSO)algorithm was employed to select the SVM model hyperparameters.Second,two feature selection algorithms,namely principal component analysis(PCA)and PSO,were integrated into the PSO-based SVM model,which generated the PCA-PSO-SVM and FS-PSO-SVM models,respectively.Three statistical metrics(accuracy,recall,and specificity)and the area under the receiver operating characteristic curve(AUC)were employed to evaluate and validate the performance of the models.The results indicated that the feature selection-based models exhibited the best performance,followed by the PSO-based SVM and SVM models.Moreover,the performance of the FS-PSO-SVM model was better than that of the PCA-PSO-SVM model,showing the highest AUC,accuracy,recall,and specificity values in both the training and testing processes.It was found that the selection of optimal features is crucial to improving the reliability of debris flow susceptibility assessment results.Moreover,the PSO algorithm was found to be not only an effective tool for hyperparameter optimization,but also a useful feature selection algorithm to improve prediction accuracies of debris flow susceptibility by using machine learning algorithms.The high and very high debris flow susceptibility zone appropriately covers 38.01%of the study area,where debris flow may occur under intensive human activities and heavy rainfall events. 展开更多
关键词 Chengde Feature selection Support vector machine Particle swarm optimization principal component analysis Debris flow susceptibility
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Fast Tensor Principal Component Analysis via Proximal Alternating Direction Method with Vectorized Technique
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作者 Haiyan Fan Gangyao Kuang Linbo Qiao 《Applied Mathematics》 2017年第1期77-86,共10页
This paper studies the problem of tensor principal component analysis (PCA). Usually the tensor PCA is viewed as a low-rank matrix completion problem via matrix factorization technique, and nuclear norm is used as a c... This paper studies the problem of tensor principal component analysis (PCA). Usually the tensor PCA is viewed as a low-rank matrix completion problem via matrix factorization technique, and nuclear norm is used as a convex approximation of the rank operator under mild condition. However, most nuclear norm minimization approaches are based on SVD operations. Given a matrix , the time complexity of SVD operation is O(mn2), which brings prohibitive computational complexity in large-scale problems. In this paper, an efficient and scalable algorithm for tensor principal component analysis is proposed which is called Linearized Alternating Direction Method with Vectorized technique for Tensor Principal Component Analysis (LADMVTPCA). Different from traditional matrix factorization methods, LADMVTPCA utilizes the vectorized technique to formulate the tensor as an outer product of vectors, which greatly improves the computational efficacy compared to matrix factorization method. In the experiment part, synthetic tensor data with different orders are used to empirically evaluate the proposed algorithm LADMVTPCA. Results have shown that LADMVTPCA outperforms matrix factorization based method. 展开更多
关键词 TENSOR principal COMPONENT ANALYSIS PROXIMAL ALTERNATING Direction Method vectorized TECHNIQUE
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Short-Term Financial Time Series Forecasting Integrating Principal Component Analysis and Independent Component Analysis with Support Vector Regression
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作者 Utpala Nanda Chowdhury Sanjoy Kumar Chakravarty Md. Tanvir Hossain 《Journal of Computer and Communications》 2018年第3期51-67,共17页
Financial time series forecasting could be beneficial for individual as well as institutional investors. But, the high noise and complexity residing in the financial data make this job extremely challenging. Over the ... Financial time series forecasting could be beneficial for individual as well as institutional investors. But, the high noise and complexity residing in the financial data make this job extremely challenging. Over the years, many researchers have used support vector regression (SVR) quite successfully to conquer this challenge. In this paper, an SVR based forecasting model is proposed which first uses the principal component analysis (PCA) to extract the low-dimensional and efficient feature information, and then uses the independent component analysis (ICA) to preprocess the extracted features to nullify the influence of noise in the features. Experiments were carried out based on 16 years’ historical data of three prominent stocks from three different sectors listed in Dhaka Stock Exchange (DSE), Bangladesh. The predictions were made for 1 to 4 days in advance targeting the short term prediction. For comparison, the integration of PCA with SVR (PCA-SVR), ICA with SVR (ICA-SVR) and single SVR approaches were applied to evaluate the prediction accuracy of the proposed approach. Experimental results show that the proposed model (PCA-ICA-SVR) outperforms the PCA-SVR, ICA-SVR and single SVR methods. 展开更多
关键词 FINANCIAL Time Series Forecasting Support vector Regression principal COMPONENT ANALYSIS Independent COMPONENT ANALYSIS Dhaka STOCK Exchange
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Cicada(Tibicen linnei) steers by force vectoring
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作者 Samane Zeyghami Nidhin Babu Haibo Dong 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2016年第2期107-111,共5页
To change flight direction, flying animals modulate aerodynamic force either relative to their bodies to generate torque about the center of mass, or relative to the flight path to produce centripetal force that curve... To change flight direction, flying animals modulate aerodynamic force either relative to their bodies to generate torque about the center of mass, or relative to the flight path to produce centripetal force that curves the trajectory. In employing the latter, the direction of aerodynamic force remains fixed in the body flame and rotations of the body redirect the force. While both aforementioned techniques are essential for flight, it is critical to investigate how an animal balances the two to achieve aerial locomotion. Here, we measured wing and body kinematics of cicada (Tibicen linnei) in flee flight, including flight periods of both little and substantial body reorientations. It is found that cicadas employ a common force vectoring technique to execute all these flights. We show that the direction of the half-stroke averaged aerodynamic force relative to the body is independent of the body orientation, varying in a range of merely 20 deg. Despite directional limitation of the aerodynamic force, pitch and roll torque are generated by altering wing angle of attack and its mean position relative to the center of mass. This results in body rotations which redirect the wing force in the global flame and consequently change the flight traiectorv. 展开更多
关键词 Cicada Free flightforce vectoring Aerial maneuver force control
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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 hain 2005 and 6336.23 thousand ha in 2010 respectively. 展开更多
关键词 arable land dynamic change driving forces principal component analysis Shandong Province
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Entropy generation analysis of thermally developing forced convection in fluid-saturated porous medium 被引量:2
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作者 K.Hooman A.Ejlali F.Hooman 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2008年第2期229-237,共9页
Entropy generation for thermally developing forced convection in a porous medium bounded by two isothermal parallel plates is investigated analytically on the basis of the Darcy flow model where the viscous dissipatio... Entropy generation for thermally developing forced convection in a porous medium bounded by two isothermal parallel plates is investigated analytically on the basis of the Darcy flow model where the viscous dissipation effects had also been taken into account. A parametric study showed that decreasing the group parameter and the Peclet number increases the entropy generation while for the Brinkman number the converse is true. Heatline visualization technique is applied with an emphasis on the Br 〈 0 case where there is somewhere that heat transfer changes direction at some streamwise location to the wall instead of its original direction, i.e., from the wall. 展开更多
关键词 entropy generation porous media heatline energy flux vectors forced convection
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Analysis to driving forces of land use change in Lu’an mining area 被引量:2
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作者 LIU Chang-hua, MA Xiao-xiao School of Surveying and Land Information Engineering, Henan Polytechnic University, Jiaozuo 454003, China 《中国有色金属学会会刊:英文版》 CSCD 2011年第S3期727-732,共6页
By selecting impact factors of driving force and formulating evaluation criteria of the impacts, the evaluation system of corresponding driving force impact of land use change was established. Taking Lu'an mining ... By selecting impact factors of driving force and formulating evaluation criteria of the impacts, the evaluation system of corresponding driving force impact of land use change was established. Taking Lu'an mining area as an example, the specific impact factors of coal mine were comprehensively evaluated and analyzed in order to carry out qualitative and quantitative analysis for the driving force of mining-land use change. The principal component analysis shows that the social and economic development in mining area from 2000 to 2007 demonstrates continuous accelerate trends, and the impacts of its overall driving force to land use change are increased gradually. The socio-economic factors have more impacts to mining-land use change than those of the natural resources. The main driving force of mining-land use change also include population, technological progress and policy. 展开更多
关键词 MINING area LAND use change driving force evaluation FACTOR principal component ANALYSIS
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Grey Relational Analysis Coupled with Principal Component Analysis Method For Optimization Design of Novel Crash Box Structure 被引量:1
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作者 Shuang Wang Dengfeng Wang 《Journal of Beijing Institute of Technology》 EI CAS 2019年第3期577-584,共8页
Crashworthiness and lightweight optimization design of the crash box are studied in this paper. For the initial model, a physical test was performed to verify the model. Then, a parametric model using mesh morphing te... Crashworthiness and lightweight optimization design of the crash box are studied in this paper. For the initial model, a physical test was performed to verify the model. Then, a parametric model using mesh morphing technology is used to optimize and decrease the maximum collision force (MCF) and increase specific energy absorption (SEA) while ensure mass is not increased. Because MCF and SEA are two conflicting objectives, grey relational analysis (GRA) and principal component analysis (PCA) are employed for design optimization of the crash box. Furthermore, multi-objective analysis can convert to a single objective using the grey relational grade (GRG) simultaneously, hence, the proposed method can obtain the optimal combination of design parameters for the crash box. It can be concluded that the proposed method decreases the MCF and weight to 16.7% and 29.4% respectively, while increasing SEA to 16.4%. Meanwhile, the proposed method in comparison to the conventional NSGA-Ⅱ method, reduces the time cost by 103%. Hence, the proposed method can be properly applied to the optimization of the crash box. 展开更多
关键词 CRASH box optimization maximum COLLISION force (MCF) specific energy absorption (SEA) GREY RELATIONAL ANALYSIS (GRA) principal component ANALYSIS (PCA)
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Sport specificity background affects the principal component structure of vertical squat jump performance of young adult female athletes 被引量:1
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作者 Vassilios Panoutsakopoulos Nikolaos Papachatzis Iraklis A.Kollias 《Journal of Sport and Health Science》 SCIE 2014年第3期239-247,共9页
Purpose: Long-term training specificity is thought to alter performance in tests evaluating strength and power production capability. The aim of the present study was to provide additional information to the limited ... Purpose: Long-term training specificity is thought to alter performance in tests evaluating strength and power production capability. The aim of the present study was to provide additional information to the limited existing knowledge concerning the possible differences of the force/time profile of squat jumping among different groups of young female athletes. Methods: One hundred and seventy-three adult women (20.1 ± 2.8 years, 1.71 ± 0.09 m, 65.6 ± 10.3 kg, mean± SD for age, height, and mass, respectively) engaged in track and field (TF), volleyball (VO), handball (HA), basketball (BA), and physical education students (PE) executed maximal squat jumps (SQJ) on a force plate. Pearson's correlation was used to identify the relationship between SQJ performance, the anthropometric characteristics and the biomechanical parameters. Differences concerning the biomechanical parameters among groups were investigated with analysis of variance, while the force- (FPD) or time- (TPD) dependency of SQJ execution was examined using principal components analysis (PCA). Results: SQJ was unrelated to body height but significantly correlated with body mass (r = -0.26, p = 0.001). TF jumped higher and produced larger peak body power output compared to all the other groups (p 〈 0.05). All athletes were superior to PE since they performed the SQJ with a longer (p 〈 0.05) vertical body center of mass trajectory during the propulsion phase. PCA results revealed that TF significantly differentiated than the other groups by relying on FPD. Conclusion: Various different profiles of FPD and TPD were detected due to different sporting background in young female athletes. Since TF superiority in SQJ was relied on the larger power production and a greater FPD, female indoor team sport athletes are suggested to execute jumping exercises adopting the jumping strategies utilized by TE 展开更多
关键词 Gender differences Performance assessment Power output principal components analysis Rate of force development
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Study on Farmland Use Change and Driving Force in the High and Cold Areas in Northwest Yunnan——A Case Study of Ninglang Yi Autonomous County
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作者 LUO Li1,YANG Zi-sheng1,KANG Yun-hai1,21.Land Resources and Sustainable Development Institute,Yunnan University of Finance and Economics,Kunming 650221,China 2.Yunnan Academy of Social Sciences,Kunming 650034,China 《Asian Agricultural Research》 2011年第3期79-82,共4页
On the basis of overview of the study area,by analyzing the dynamic change of farmland in Ninglang County,we can find that the farmland area in this county tended to decrease from 1996 to 2008.According to the investi... On the basis of overview of the study area,by analyzing the dynamic change of farmland in Ninglang County,we can find that the farmland area in this county tended to decrease from 1996 to 2008.According to the investigation data concerning land change provided by Bureau of Land and Resources in Ninglang County and socio-economic data provided by Bureau of Statistics in Ninglang County,we select 11 indices,such as total population,GDP,total output value of county and so on,coupled with SPSS statistical method,we adopt principal component analysis method to analyze driving force factors of farmland use change in the high and cold areas in Northwest Yunnan.The results show that the two factors of economic development and population growth are the dominant driving factors impacting farmland use change,and the policy factors,such as "returning farmland to forests",are also the important driving factors impacting Ninglang County. 展开更多
关键词 Changes of FARMLAND Driving force principal compon
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Influence of Regular Wave and Ship Characteristics on Mooring Force Prediction by Data-Driven Model
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作者 LIU Bi-jin CHEN Xiao-yun +2 位作者 ZHANG You-quan XIE Jing CHANG Jiang 《China Ocean Engineering》 SCIE EI CSCD 2020年第4期589-596,共8页
The study of mooring forces is an important issue in marine engineering and offshore structures.Although being widely applied in mooring system,numerical simulations suffer from difficulties in their multivariate and ... The study of mooring forces is an important issue in marine engineering and offshore structures.Although being widely applied in mooring system,numerical simulations suffer from difficulties in their multivariate and nonlinear modeling.Data-driven model is employed in this paper to predict the mooring forces in different lines,which is a new attempt to study the mooring forces.The height and period of regular wave,length of berth,ship load,draft and rolling period are considered as potential influencing factors.Input variables are determined using mutual information(MI)and principal component analysis(PCA),and imported to an artificial neural network(NN)model for prediction.With study case of 200 and 300 thousand tons ships experimental data obtained in Dalian University of Technology,MI is found to be more appropriate to provide effective input variables than PCA.Although the three factors regarding ship characteristics are highly correlated,it is recommended to input all of them to the NN model.The accuracy of predicting aft spring line force attains as high as 91.2%.The present paper demonstrates the feasibility of MI-NN model in mapping the mooring forces and their influencing factors. 展开更多
关键词 mooring force characteristics of ship neural network mutual information principal component analysis
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Relationship between Creasing-Recovery Force and Crease-Recovery Angle
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作者 陈美玉 来侃 +2 位作者 孙润军 武晖 武燕 《Journal of Donghua University(English Edition)》 EI CAS 2010年第1期113-116,共4页
To find out the reason of resulting in the crease recovery of a fabric and provide theoretical guidance for designing a new material with good creasing-recovery property,the relationship between the creasing-recovery ... To find out the reason of resulting in the crease recovery of a fabric and provide theoretical guidance for designing a new material with good creasing-recovery property,the relationship between the creasing-recovery force and the crease-recovery angle of a woven fabric was investigated by self-setup experimental device.The results show that the crease-recovery angle of a woven fabric is correlated with the creasing-recovery force of the fabric in a linear relation.Furthermore,it is found that the internal stress is the principal force of affecting the creasing-recovery property of a woven fabric.In addition,the relationship between the tensile property of a woven fabric and the creasing-recovery property of the fabric has also been investigated,showing that the lower relaxation velocity of tensile stress of a fabric is,the better creasing-recovery property of the fabric has. 展开更多
关键词 crease-recovery angle creasing-recovery force creasing-recovery property internal stress principal force
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Three-dimensional atomic force microscopy based on tailored cantilever probe with flared tip
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作者 ZHANG Rui WU Sen +3 位作者 XIAO Sha-sha HU Xiao-dong SHI Yu-shu FU Xing 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2020年第4期388-396,共9页
In order to meet the requirements of nondestructive testing of true 3D topography of micro-nano structures,a novel three-dimensional atomic force microscope(3D-AFM)based on flared tip is developed.A high-precision sca... In order to meet the requirements of nondestructive testing of true 3D topography of micro-nano structures,a novel three-dimensional atomic force microscope(3D-AFM)based on flared tip is developed.A high-precision scanning platform is designed to achieve fast servo through moving probe and sample simultaneously,and several combined nanopositioning stages are used to guarantee linearity and orthogonality of displacement.To eliminate the signal deviation caused by AFM-head movement,a traceable optical lever system is designed for cantilever deformation detection.In addition,a method of tailoring the cantilever of commercial probe with flared tip is proposed to reduce the lateral force applied on the tip in measurement.The tailored probe is mounted on the 3D-AFM,and 3D imaging experiments are conducted on different samples by use of adaptive-angle scanning strategy.The results show the roob-mean-square value of the vertical displacement noise(RMS)of the prototype is less than 0.1 nm and the high/width measurement repeatability(peak-to-peak)is less than 2.5 nm. 展开更多
关键词 three-dimensional atomic force microscope(3D-AFM) flared tip SCANNER optical lever vector scanning
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