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WPPSI-III in Sudan:Validity,reliability,and confirmatory factor analysis in khartoum kindergarten and primary schools
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作者 Rwaa Omer Ali Ahmed Salaheldin Farah Attallah Bakhiet +2 位作者 Ayman Mohamed Taha Abdelaziz Ahmed FadlAlMawla AbdulRadi Ismael Salamah Albursan 《Journal of Psychology in Africa》 2025年第4期431-439,共9页
The study aims to determine the validity and reliability of the Wechsler Preschool and Primary Scale of Intelligence–Third Edition(WPPSI-III)scores in a sample of kindergarten and lower primary pupils from Khartoum S... The study aims to determine the validity and reliability of the Wechsler Preschool and Primary Scale of Intelligence–Third Edition(WPPSI-III)scores in a sample of kindergarten and lower primary pupils from Khartoum State,Sudan.It also aims to examine whether test’s factor structure in this sample replicated that of the original WPPSI-III.The study sample consisted of 384 kindergarten and primary school children in Khartoum State(females=50%mean age=4.14,SD=1.37),selected using stratified random sampling across its seven localities:Khartoum,Jebel Awliya,Khartoum Bahri,East Nile,Omdurman,Ombada,Karari.For concurrent validation,the children additionally completed the Goodenough Draw-a-Man Test,and the Colored Progressive Matrices.WPPSI-III scores demonstrated high internal consistency across the subtest items.Confirmatory factor analysis indicators for total,verbal,and performance intelligence were all excellent.The scale also showed weak to strong score stability ranging from 0.25(weak)to 0.88(strong)based on the Spearman-Brown equation,0.25 to 0.75 based on the Guttman split-half method.The Cronbach’s alpha coefficient scores ranged from 0.54 to 0.93.The WPPSI-III and Goodenough Draw-a-Man Test scores concurrent validity scores were poor(0.05)to modest(0.31),and while those with the Colored Progressive Matrices test were poor(r=0.04–0.18).Thesefindings provide evidence to suggest that the WPPSI-III is appropriate for research use with kindergarten and lower primary school students in Khartoum State,Sudan. 展开更多
关键词 intelligence tests VALIDATION RELIABILITY primary schools kindergartens confirmatory factor analysis cognitive abilities WPPSI-III SUDAN
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Research on the Construction of an Evaluation System for Innovation and Entrepreneurship Capabilities of Normal University Students Based on Factor Analysis Method
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作者 Fang Liu Chi Li Lihua Jia 《Journal of Contemporary Educational Research》 2025年第8期320-327,共8页
Under the National Innovation-Driven Development Strategy,establishing a scientifically sound evaluation system for normal university students’innovation and entrepreneurship capabilities serves as a crucial foundati... Under the National Innovation-Driven Development Strategy,establishing a scientifically sound evaluation system for normal university students’innovation and entrepreneurship capabilities serves as a crucial foundation for optimizing innovation education models and enhancing teacher candidates’comprehensive competencies.Based on existing indicator frameworks,we designed a questionnaire and applied exploratory factor analysis(EFA)to screen indicators,reduce dimensionality,and analyze weighting.This process identified key metrics for evaluating pedagogical students’innovation capacities,ultimately constructing a targeted assessment system for normal university students.The study provides theoretical support for cultivating teacher trainees’innovative capabilities while contributing to the national innovation strategy implementation. 展开更多
关键词 factor analysis Innovation and entrepreneurship capability Indicator system Evaluation system UNIVERSITIES Normal university students
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Factor analysis and machine learning for predicting endpoint carbon content in converter steelmaking
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作者 Lihua Zhao Shuai Yang +3 位作者 Yongzhao Xu Zhongliang Wang Xin Liu Yanping Bao 《International Journal of Minerals,Metallurgy and Materials》 2025年第10期2469-2482,共14页
The endpoint carbon content in the converter is critical for the quality of steel products,and accurately predicting this parameter is an effective way to reduce alloy consumption and improve smelting efficiency.Howev... The endpoint carbon content in the converter is critical for the quality of steel products,and accurately predicting this parameter is an effective way to reduce alloy consumption and improve smelting efficiency.However,most scholars currently focus on modifying methods to enhance model accuracy,while overlooking the extent to which input parameters influence accuracy.To address this issue,in this study,a prediction model for the endpoint carbon content in the converter was developed using factor analysis(FA)and support vector machine(SVM)optimized by improved particle swarm optimization(IPSO).Analysis of the factors influencing the endpoint carbon content during the converter smelting process led to the identification of 21 input parameters.Subsequently,FA was used to reduce the dimensionality of the data and applied to the prediction model.The results demonstrate that the performance of the FA-IPSO-SVM model surpasses several existing methods,such as twin support vector regression and support vector machine.The model achieves hit rates of 89.59%,96.21%,and 98.74%within error ranges of±0.01%,±0.015%,and±0.02%,respectively.Finally,based on the prediction results obtained by sequentially removing input parameters,the parameters were classified into high influence(5%-7%),medium influence(2%-5%),and low influence(0-2%)categories according to their varying degrees of impact on prediction accuracy.This classi-fication provides a reference for selecting input parameters in future prediction models for endpoint carbon content. 展开更多
关键词 CONVERTER endpoint carbon content parameter classification factor analysis improved particle swarm optimization support vector machine
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Nursing interventions’impact on cardiovascular complications after gastrointestinal surgery in intensive care unit:Risk factor analysis
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作者 Ling Wang Peng Yang +1 位作者 Xue-Qing He Han Xia 《World Journal of Gastrointestinal Surgery》 2025年第8期133-141,共9页
BACKGROUND Cardiovascular(CV)complications are common in intensive care unit(ICU)patients after gastrointestinal surgery and are associated with increased mortality and prolonged hospital stay.The optimization of post... BACKGROUND Cardiovascular(CV)complications are common in intensive care unit(ICU)patients after gastrointestinal surgery and are associated with increased mortality and prolonged hospital stay.The optimization of postoperative nursing interventions,particularly pain management,is crucial for reducing such complications.AIM To investigate the effects of enhanced recovery nursing on CV complications after gastrointestinal surgery in ICU patients and associated risk factors.METHODS A retrospective analysis was conducted on 78 adult patients who underwent gastrointestinal surgery in the ICU of our hospital between February 2023 and September 2024.Among them,40 patients received standard care(control group),while 38 received enhanced recovery nursing(observation group).We compared the incidence of CV complications and nursing satisfaction between the two groups.Patients were divided into CV complication and non-complication groups based on complication occurrence,and logistic regression analysis was used to identify risk factors.RESULTS In the control and observation groups,the incidence of CV complications was 30.0%(12/40)and 18.4%(7/38),with a nursing satisfaction rate of 70.0%(28/40)and 92.1%(35/38),respectively.The postoperative pain score at 14 days was significantly lower in the observation group(0.27±0.15)compared to the control group(1.65±0.37),with all differences being statistically significant(P<0.05).Univariate analysis indicated significant differences in age,body mass index,hypertension,diabetes,smoking history,history of heart failure,and previous myocardial infarction(P<0.05).Multivariate logistic regression identified heart failure history,previous myocardial infarction,age,hypertension,and diabetes as independent risk factors,with odds ratios of 1.195,1.528,1.062,1.836,and 1.942,respectively(all P<0.05).CONCLUSION Implementing enhanced recovery nursing for ICU patients after gastrointestinal surgery is beneficial in reducing the incidence of CV complications and improving nursing satisfaction. 展开更多
关键词 Enhanced recovery nursing interventions Intensive care unit Gastrointestinal surgery Cardiovascular complications Risk factor analysis
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A State-Migration Particle Swarm Optimizer for Adaptive Latent Factor Analysis of High-Dimensional and Incomplete Data
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作者 Jiufang Chen Kechen Liu +4 位作者 Xin Luo Ye Yuan Khaled Sedraoui Yusuf Al-Turki MengChu Zhou 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第11期2220-2235,共16页
High-dimensional and incomplete(HDI) matrices are primarily generated in all kinds of big-data-related practical applications. A latent factor analysis(LFA) model is capable of conducting efficient representation lear... High-dimensional and incomplete(HDI) matrices are primarily generated in all kinds of big-data-related practical applications. A latent factor analysis(LFA) model is capable of conducting efficient representation learning to an HDI matrix,whose hyper-parameter adaptation can be implemented through a particle swarm optimizer(PSO) to meet scalable requirements.However, conventional PSO is limited by its premature issues,which leads to the accuracy loss of a resultant LFA model. To address this thorny issue, this study merges the information of each particle's state migration into its evolution process following the principle of a generalized momentum method for improving its search ability, thereby building a state-migration particle swarm optimizer(SPSO), whose theoretical convergence is rigorously proved in this study. It is then incorporated into an LFA model for implementing efficient hyper-parameter adaptation without accuracy loss. Experiments on six HDI matrices indicate that an SPSO-incorporated LFA model outperforms state-of-the-art LFA models in terms of prediction accuracy for missing data of an HDI matrix with competitive computational efficiency.Hence, SPSO's use ensures efficient and reliable hyper-parameter adaptation in an LFA model, thus ensuring practicality and accurate representation learning for HDI matrices. 展开更多
关键词 Data science generalized momentum high-dimensional and incomplete(HDI)data hyper-parameter adaptation latent factor analysis(LFA) particle swarm optimization(PSO)
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Factor Analysis Based on the Level of Urban Facilities in Different Regions 被引量:1
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作者 于淼 《Agricultural Science & Technology》 CAS 2017年第6期1102-1105,共4页
With the rapid growth of economy in China, people's living standard has been generally improved, and people's requirements on the quality and quantity of infrastructures like transportation convenience, city greenin... With the rapid growth of economy in China, people's living standard has been generally improved, and people's requirements on the quality and quantity of infrastructures like transportation convenience, city greening have become higher and higher, which requires the government to attach importance to these livelihood is- sues. Based on the China Statistical Yearbook, 6 target factors of 31 provinces and cities in China were conducted with factor analysis, and the conditions of the infras- tructures in the 31 provinces and cities were judged and evaluated through the ex- traction of common factors and the calculation of these common factors, and corre- sponding suggestions were proposed with the aim to improve the infrastructures in China. 展开更多
关键词 factor analysis INFRASTRUCTURE EVALUATION
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Characterization of dissolved organic matter in urban sewage using excitation emission matrix fluorescence spectroscopy and parallel factor analysis 被引量:41
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作者 Weidong Guo Jing Xu +3 位作者 Jiangping Wang Yingrou Wen Jianfu Zhuo Yuchao Yan 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2010年第11期1728-1734,共7页
Wastewater dissolved organic matter (DOM) from different processing stages of a sewage treatment plant in Xiamen was characterized using fluorescence and absorption spectroscopy. Parallel factor analysis modeling of... Wastewater dissolved organic matter (DOM) from different processing stages of a sewage treatment plant in Xiamen was characterized using fluorescence and absorption spectroscopy. Parallel factor analysis modeling of excitation-emission matrix spectra revealed five fluorescent components occurring in sewage DOM: one protein-like (C1), three humic-like (C2, C4 and C5) and one xenobiotic-like (C3) components. During the aerated grit chamber and primary sedimentation tank stage, there was only a slight decrease in fluorescence intensity and the absorption coefficient at 350 nm (a 350 ). During the second aeration stage, high concentration of protein-like and short-wavelength-excited humic-like components were significantly degraded accompanied by significant loss of DOC (80%) and a 350 (30%), indicating that C1 and C2 were the dominant constituents of sewage DOM. As a result, long-wavelength- excited C4 and C5 became the dominant humic-like components and the DOM molecular size inferred from the variation of spectral slope S (300–650 nm) and specific absorption (a 280 /DOC) increased. Combination use of F max of C1 and the ratio of C1/C5, or a 350 may provide a quantitative indication for the relative amount of raw or treated sewage in aquatic environment. 展开更多
关键词 dissolved organic matter SEWAGE fluorescence EEM parallel factor analysis
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An unsupervised pattern recognition methodology based on factor analysis and a genetic-DBSCAN algorithm to infer operational conditions from strain measurements in structural applications 被引量:7
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作者 Juan Carlos PERAFAN-LOPEZ Julian SIERRA-PEREZ 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2021年第2期165-181,共17页
Structural Health Monitoring(SHM) suggests the use of machine learning algorithms with the aim of understanding specific behaviors in a structural system. This work introduces a pattern recognition methodology for ope... Structural Health Monitoring(SHM) suggests the use of machine learning algorithms with the aim of understanding specific behaviors in a structural system. This work introduces a pattern recognition methodology for operational condition clustering in a structure sample using the well known Density Based Spatial Clustering of Applications with Noise(DBSCAN) algorithm.The methodology was validated using a data set from an experiment with 32 Fiber Bragg Gratings bonded to an aluminum beam placed in cantilever and submitted to cyclic bending loads under 13 different operational conditions(pitch angles). Further, the computational cost and precision of the machine learning pipeline called FA + GA-DBSCAN(which employs a combination of machine learning techniques including factor analysis for dimensionality reduction and a genetic algorithm for the automatic selection of initial parameters of DBSCAN) was measured. The obtained results have shown a good performance, detecting 12 of 13 operational conditions, with an overall precision over 90%. 展开更多
关键词 CLUSTERING DBSCAN factor analysis FBGs Pattern recognition Strain field
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Simulated photo-degradation of dissolved organic matter in lakes revealed by three-dimensional excitation-emission matrix with regional integration and parallel factor analysis 被引量:4
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作者 Jin Zhang Fanhao Song +5 位作者 Tingting Li Kefu Xie Huiying Yao Baoshan Xing Zhongyu Li Yingchen Bai 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2020年第4期310-320,共11页
Simulated photo-degradation of fluorescent dissolved organic matter(FDOM) in Lake Baihua(BH) and Lake Hongfeng(HF) was investigated with three-dimensional excitationemission matrix(3 DEEM) fluorescence combined with t... Simulated photo-degradation of fluorescent dissolved organic matter(FDOM) in Lake Baihua(BH) and Lake Hongfeng(HF) was investigated with three-dimensional excitationemission matrix(3 DEEM) fluorescence combined with the fluorescence regional integration(FRI),parallel factor(PARAFAC) analysis,and multi-order kinetic models.In the FRI analysis,fulvic-like and humic-like materials were the main constituents for both BH-FDOM and HF-FDOM.Four individual components were identified by use of PARAFAC analysis as humic-like components(C1),fulvic-like components(C2),protein-like components(C3) and unidentified components(C4).The maximum 3 DEEM fluorescence intensity of PARAFAC components C1-C3 decreased by about 60%,70% and 90%,respectively after photo-degradation.The multi-order kinetic model was acceptable to represent the photo-degradation of FDOM with correlation coefficient(Radj2)(0.963-0.998).The photo-degradation rate constants(kn) showed differences of three orders of magnitude,from 1.09 × 10-6 to 4.02 × 10-4 min-1,and half-life of multi-order model(T1/2n)ranged from 5.26 to 64.01 min.The decreased values of fluorescence index(FI) and biogenic index(BI),the fact that of percent fluorescence response parameter of Region I(PⅠ,n) showed the greatest change ratio,followed by percent fluorescence response parameter of Region II(PⅡ,n,while the largest decrease ratio was found for C3 components,and the lowest T1/2n was observed for C3,indicated preferential degradation of protein-like materials/components derived from biological sources during photodegradation.This research on the degradation of FDOM by 3 DEEM/FRI-PARAFAC would be beneficial to understanding the photo-degradation of FD OM in natural environments and accurately predicting the environmental behaviors of contaminants in the presence of FDOM. 展开更多
关键词 Fluorescent dissolved organic matter PHOTO-DEGRADATION Fluorescence regional integration Parallel factor analysis Three-dimensional excitationemission matrix Multi-order kinetic models
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Rutting influencing factors and prediction model for asphalt pavements based on the factor analysis method 被引量:5
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作者 Liu Gang Chen Leilei +1 位作者 Qian Zhendong Zhou Xiayang 《Journal of Southeast University(English Edition)》 EI CAS 2021年第4期421-428,共8页
To clarify the importance of various influencing factors on asphalt pavement rutting deformation and determine a screening method of model indicators,the data of the RIOHTrack full-scale track were examined using the ... To clarify the importance of various influencing factors on asphalt pavement rutting deformation and determine a screening method of model indicators,the data of the RIOHTrack full-scale track were examined using the factor analysis method(FAM).Taking the standard test pavement structure of RIOHTrack as an example,four rutting influencing factors from different aspects were determined through statistical analysis.Furthermore,the common influencing factors among the rutting influencing factors were studied based on FAM.Results show that the common factor can well characterize accumulative ESALs,center-point deflection,and temperature,besides humidity,which indicates that these three influencing factors can have an important impact on rutting.Moreover,an empirical rutting prediction model was established based on the selected influencing factors,which proved to exhibit high prediction accuracy.These analysis results demonstrate that the FAM is an effective screening method for rutting prediction model indicators,which provides a reference for the selection of independent model indicators in other rutting prediction model research when used in other areas and is of great significance for the prediction and control of rutting distress. 展开更多
关键词 asphalt pavement rutting prediction influencing factors RIOHTrack full-scale track factor analysis method
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Factor analysis identifies subgroups of constipation 被引量:3
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作者 Philip G Dinning Mike Jones +6 位作者 Linda Hunt Sergio E Fuentealba Jamshid Kalanter Denis W King David Z Lubowski Nicholas J Talley Ian J Cook 《World Journal of Gastroenterology》 SCIE CAS CSCD 2011年第11期1468-1474,共7页
AIM:To determine whether distinct symptom groupings exist in a constipated population and whether such grouping might correlate with quantifiable pathophysiological measures of colonic dysfunction.METHODS:One hundred ... AIM:To determine whether distinct symptom groupings exist in a constipated population and whether such grouping might correlate with quantifiable pathophysiological measures of colonic dysfunction.METHODS:One hundred and ninety-one patients presenting to a Gastroenterology clinic with constipation and 32 constipated patients responding to a newspaper advertisement completed a 53-item,wide-ranging selfreport questionnaire.One hundred of these patients had colonic transit measured scintigraphically.Factor analysis determined whether constipation-related symptoms grouped into distinct aspects of symptomatology.Cluster analysis was used to determine whether indi-vidual patients naturally group into distinct subtypes.RESULTS:Cluster analysis yielded a 4 cluster solution with the presence or absence of pain and laxative unresponsiveness providing the main descriptors.Amongst all clusters there was a considerable proportion of patients with demonstrable delayed colon transit,irritable bowel syndrome positive criteria and regular stool frequency.The majority of patients with these characteristics also reported regular laxative use.CONCLUSION:Factor analysis identified four constipation subgroups,based on severity and laxative unresponsiveness,in a constipated population.However,clear stratification into clinically identifiable groups remains imprecise. 展开更多
关键词 factor analysis CONSTIPATION SYMPTOMS CLUSTERS LAXATIVES
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Factor analysis of earthquake-induced geological disasters of the M7.0 Lushan earthquake in China 被引量:3
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作者 Li Xue Liu Xiaoli +3 位作者 Li Jinggang Wang Qiuliang Liao Wulin Zhang Lifen 《Geodesy and Geodynamics》 2013年第2期22-29,共8页
The seismic intensities, lithologic characteristics and terrain features from a 3000 km2-region near the epicenter of the Lushan earthquake are used to analyze earthquake-induced geological disaster. The preliminary r... The seismic intensities, lithologic characteristics and terrain features from a 3000 km2-region near the epicenter of the Lushan earthquake are used to analyze earthquake-induced geological disaster. The preliminary results indicate that secondary effects of the earthquake will affect specific areas, including those with glutenite and carbonate bedrock, a seismic intensity of IX, slopes between 40° and 50°, elevations of less than 2500 m, slope change rates between 20° and 30°, slope curvatures from - 1 to -0.5 and 0. 5 to 1, and relief between 50 and 100 m. Regions with susceptibility indices greater than 0.71 are prone to landslides and collapses. The secondary features are mainly distributed on both sides of the ridges that extend from Baosheng to Shuangshi and from Baosheng to Longxing. Other features are scattered on both sides of the ridges that extend from Qishuping to Baosheng and from Masangping to Lingguan. The distribution of the earthquake-related features trends in the NE direction, and the area that was most affected by the Lushan earthquake covers approximately 52.4 km^2. 展开更多
关键词 Lushan earthquake earthquake-induced geological disaster factor analysis susceptibility index hazard distribution
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Measuring speed consistency for freeway diverge areas using factor analysis 被引量:2
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作者 曲栩 郭唐仪 +1 位作者 王炜 胡启洲 《Journal of Central South University》 SCIE EI CAS 2013年第1期267-273,共7页
Although either absolute speed or speed difference can be considered as a measure for speed consistency, few researches consider both in practice. The factor analysis method was introduced to extract an optimal number... Although either absolute speed or speed difference can be considered as a measure for speed consistency, few researches consider both in practice. The factor analysis method was introduced to extract an optimal number of factors from numerous original measures. The freeway diverging zone was divided into four elements, namely the upstream, the diverge area, the downstream and the exit ramp. Operating speeds together with individual vehicle speeds were collected at each element with radar guns. Following the factor analysis procedure, two factors, which explain 96.722% of the variance in the original data, were retained from the initial seven speed measures. According to the loadings after Varimax rotation, the two factors are clearly classified into two categories. The first category is named "speed scale" reflecting the absolute speed, and the other one is named "speed dispersion" interpreting speed discreteness. Then, the weighted score of speed consistency for each diverge area is given in terms of linear combination of the two retained factors. To facilitate the level classification of speed consistency, the weighted scores are normalized in the range of (0, 1.0). The criterion for speed consistency classification is given as 0≤F N <0.30, good consistency; 0.30≤F N <0.60, fair consistency; 0.60≤ F N ≤1.00, poor consistency. The validation by comparing with previously developed measures shows that the proposed measure is acceptable in evaluating speed consistency. 展开更多
关键词 SAFETY FREEWAY speed consistency factor analysis
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Modifying the Autism Spectrum Rating Scale(6–18 years)to a Chinese Context:An Exploratory Factor Analysis 被引量:10
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作者 Hao Zhou Lili Zhang +10 位作者 Xuerong Luo Lijie Wu Xiaobing Zou Kun Xia Yimin Wang Xiu Xu Xiaoling Ge Yong-Hui Jiang Eric Fombonne Weili Yan Yi Wang 《Neuroscience Bulletin》 SCIE CAS CSCD 2017年第2期175-182,共8页
The purpose of this study was to explore the psychometric properties of the Chinese version of the autism spectrum rating scale(ASRS). We recruited 1,625community-based children and 211 autism spectrum disorder(ASD... The purpose of this study was to explore the psychometric properties of the Chinese version of the autism spectrum rating scale(ASRS). We recruited 1,625community-based children and 211 autism spectrum disorder(ASD) cases from 4 sites, and the parents of all participants completed the Chinese version of the ASRS. A robust weighted least squares means and variance adjusted estimator was used for exploratory factor analysis. The3-factor structure included 59 items suitable for the current sample. The item reliability for the modi?ed Chinese version of the ASRS(MC-ASRS) was excellent. Moreover,with 60 as the cut-off point, receiver operating characteristic analysis showed that the MC-ASRS had excellent discriminate validity, comparable to that of the unmodi?ed Chinese version(UC-ASRS), with area under the curve values of 0.952(95% CI: 0.936–0.967) and 0.948(95% CI:0.930–0.965), respectively. Meanwhile, the con?rm factor analysis revealed that MC-ASRS had a better construct validity than UC-ASRS based on the above factor solution in another children sample. In conclusion, the MC-ASRS shows better ef?cacy in epidemiological screening for ASD in Chinese children. 展开更多
关键词 Autism spectrum disorder Screening Epidemiology Exploratory factor analysis Children
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Analysis of factors influencing the Henry Hub natural gas price based on factor analysis 被引量:2
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作者 Hong Li Hui-Ming Zhang +1 位作者 Yuan-Tao Xie Di Wang 《Petroleum Science》 SCIE CAS CSCD 2017年第4期822-830,共9页
Henry Hub as an important transaction hub for natural gas sets the gas price standard in the USA. In this paper, the factors influencing Henry Hub natural gas prices are analyzed, and the major factors determining the... Henry Hub as an important transaction hub for natural gas sets the gas price standard in the USA. In this paper, the factors influencing Henry Hub natural gas prices are analyzed, and the major factors determining the price levels in the period between January 1997 and December 2016 are studied. It is found that economic conditions, total energy demand, US dollar exchange rate and gas consumption are the major factors. The mechanism of each factor influencing the Henry Hub natural gas price is also explored in the paper. 展开更多
关键词 Natural gas Henry Hub factor analysis
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Analysis of inhomogeneity of solidified microstructure of continuous casting copper tubular billet based on factor analysis 被引量:2
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作者 Jin-song Liu Chao-rui Shan +3 位作者 Da-yong Chen Hong-wu Song Chuan-lai Chen Yun-yue Chen 《China Foundry》 SCIE EI CAS CSCD 2023年第6期526-536,共11页
The horizontal continuous casting process,the initial step in TP2 copper tubular processing,directly determines the microstructure and properties of copper tubular.However,the process parameters of the continuous cast... The horizontal continuous casting process,the initial step in TP2 copper tubular processing,directly determines the microstructure and properties of copper tubular.However,the process parameters of the continuous casting characterize time variation,multiple disturbances and strong coupling.As a consequence,their influence on a casting billet is difficult to be determined.Due to the above issues,the common factor and special factor analysis of the factor analysis model were used in this study,and the casting experiment and billet metallographic experiment were carried out to diagnose and analyze the reason of the microstructure inhomogeneity.The multiple process parameters were studied and classified using common factor analysis,2 the cast billets with abnormal microstructures were identified by GT^(2) statistics,and the most important factors affecting the microstructural homogeneity were found by special factor analysis.The calculated and experimental results show that the principal parameters influencing the inhomogeneity of solidified microstructure are the primary inlet water pressure and the primary outlet water temperature.According to the consequence of the above investigation,the inhomogeneity of the copper billet microstructure can be effectively improved when the process parameters are controlled and adjusted. 展开更多
关键词 TP2 copper tubular billet horizontal continuous casting factor analysis microstructure inhomogeneity of casting billet quality diagnosis
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Evaluation and classification of residential greenbelt quality based on factor analysis & clustering analysis:An example of Xinxiang City,China 被引量:1
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作者 乔丽芳 张毅川 齐安国 《Journal of Forestry Research》 SCIE CAS CSCD 2008年第4期311-314,共4页
Five factors expressing greenbelt quality and one factor expressing quantity were adopted for evaluation of the residential greenbelt, and the AHP (Analytical Hierarchy Process) method was used to determine the valu... Five factors expressing greenbelt quality and one factor expressing quantity were adopted for evaluation of the residential greenbelt, and the AHP (Analytical Hierarchy Process) method was used to determine the value of factors. Thirty residential areas were selected as the samples. Two principal components were extracted and their expression was constructed by method of factor anlysis, therefore, quality evaluation of residential greenbelt was obtained. The accuracy of the function and implement quality classification toward the residential greenbelts in Xinxiang City were validated by clustering analysis method. The results showed that the greenbelt quality of fourteen residential areas was higher than the average level, of which eleven were newly-built residential areas. The 30 residential areas were classified into three types according to their greenbelt features and their formation by clustering analysis method. Finally rational proposal basing on aforesaid evaluating results was proposed for construction and renewal of residential greenbelt, upon which directive basis was provided for construction and renewal of residential greenbelt. 展开更多
关键词 residential area greenbelt quality EVALUATION factor analysis clustering analysis
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Discrimination of marine algal taxonomic groups based on fluorescence excitation emission matrix, parallel factor analysis and CHEMTAX 被引量:1
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作者 CHEN Xiaona SU Rongguo +2 位作者 BAI Ying SHI Xiaoyong YANG Rujun 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2014年第12期192-205,共14页
An in vivo three-dimensional fluorescence method for the determination of algae community structure was developed by parallel factor analysis (PARAFAC) and CHEMTAX. The PARAFAC model was applied to fluo-rescence exc... An in vivo three-dimensional fluorescence method for the determination of algae community structure was developed by parallel factor analysis (PARAFAC) and CHEMTAX. The PARAFAC model was applied to fluo-rescence excitation-emission matrix (EEM) of 60 algae species belonging to five divisions and 11 fluorescent components were identified according to the residual sum of squares and specificity of the composition profiles of fluorescent. By the 11 fluorescent components, the algae species at different growth stages were classified correctly at the division level using Bayesian discriminant analysis (BDA). Then the reference fluo-rescent component ratio matrix was constructed for CHEMTAX, and the EEM-PARAFAC-CHEMTAX method was developed to differentiate algae taxonomic groups. The correct discrimination ratios (CDRs) when the fluorometric method was used for single-species samples were 100% at the division level, except for Bacil-lariophyta with a CDR of 95.6%. The CDRs for the mixtures were above 94.0% for the dominant algae species and above 87.0% for the subdominant algae species. However, the CDRs of the subdominant algae species were too low to be unreliable when the relative abundance estimated was less than 15.0%. The fluorometric method was tested using the samples from the Jiaozhou Bay and the mesocosm experiments in the Xiaomai Island Bay in August 2007. The discrimination results of the dominant algae groups agreed with microscopy cell counts, as well as the subdominant algae groups of which the estimated relative abundance was above 15.0%. This technique would be of great aid when low-cost and rapid analysis is needed for samples in a large batch. The fluorometric technique has the ability to correctly identify dominant species with proper abundance both in vivo and in situ. 展开更多
关键词 CHEMTAX fluorescence excitatiqn-emission matrices in vivo fluorescent components parallel factor analysis PHYTOPLANKTON
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Modeling Indicator Systems for Evaluating Environmental Sustainable Development Based on Factor Analysis 被引量:1
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作者 WU Hao CHEN Xiaoling +3 位作者 HE Ying HE Xiaorong CAI Xiaobin XU Keya 《Wuhan University Journal of Natural Sciences》 CAS 2006年第4期997-1002,共6页
Indicator systems of environmental sustainable development in the Poyang Lake Basin are established from 51 elementary indexes by factor analysis, which is composed of four steps such as the factor model, the paramete... Indicator systems of environmental sustainable development in the Poyang Lake Basin are established from 51 elementary indexes by factor analysis, which is composed of four steps such as the factor model, the parameter estimation, the factor rotation and the factor score. Under the condition that the cumulative proportion is greater than 85%, 5 explicit factors of environmental sustainable development as well as its factor score by region are carried out. The result indicates some impact factors to the basin environmental in descending sort order are volume of water, volume of waste gas discharge,volume of solid wasters.the degree to comprehensive utilization of waste gas, waste water and solid wastes, the emission volume of waste gas, waste water and solid wastes. It is helpful and important to provide decision support for constituting sustainable development strategies and evaluate the sustainable development status of each city. 展开更多
关键词 factor analysis the Poyang Lake Basin environment evaluation sustainable development indicator systems
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Long-Term Outcome and Risk Factor Analysis of Surgical Pulmonary Valve Replacement in Congenital Heart Disease 被引量:1
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作者 Woo Young Park Gi Beom Kim +7 位作者 Sang Yun Lee Mi Kyoung Song Hye Won Kwon Hyo Soon An Eun Jung Bae Sungkyu Cho Jae Gun Kwak Woong-Han Kim 《Congenital Heart Disease》 SCIE 2022年第3期335-350,共16页
Objectives:To establish long-term outcome of surgical pulmonary valve replacement(PVR)in congenital heart disease(CHD)and to identify risk factors for overall mortality,operative mortality,and repetitive PVR.Methods:T... Objectives:To establish long-term outcome of surgical pulmonary valve replacement(PVR)in congenital heart disease(CHD)and to identify risk factors for overall mortality,operative mortality,and repetitive PVR.Methods:This is a retrospective study of 375 surgical PVR in 293 patients who underwent surgical PVR for CHD between January 2000 and May 2020.We only included patients with index PVR with previous open-heart surgery regardless of the number of PVRs.The previous surgical history of patients who underwent PVR during the study period was also included.Patients who underwent the Rastelli operation,and those who underwent single PVR without previous open-heart surgery were excluded.Results:The median age of the patients at the time of surgical PVR was 14.9 years(Interquartile range,IQR,11.0–22.0).The median follow-up duration was 10.5 years(IQR,5.5–14.8 years).There were 3 patients with operative mortality(1.0%)and 15 patients with overall mortality(5.1%).The survival rate was 95.1%over 20 years follow-up period.Multivariate analysis demonstrated that more than 3 times of previous open-heart surgeries before surgical PVR,older age at the first operation,longer cardiopulmonary bypass(CPB)time and longer intensive care unit(ICU)stay were predictors for overall mortality.Patients who underwent surgical PVR after more than 3 times of previous open-heart surgeries had significantly higher mortality than those who underwent open-heart surgeries less than 3 times(P<0.001).Age younger than 10 years,male,multiple valve problems and longer ICU stay were significant predictors for repetitive PVR by multivariate analysis.Conclusions:Though surgical PVR has excellent long-term outcome,it should be performed with caution for those who previously underwent multiple open-heart surgeries,especially if patient received more than 3 times of open-heart surgeries. 展开更多
关键词 Pulmonary valve replacement MORTALITY operative mortality repetitive pulmonary valve replacement risk factor analysis CHILDHOOD
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