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Chinese Journal of Aeronautics 2021年第2期34卷 165-181页

作者： Juan Carlos PERAFAN-LOPEZ Julian SIERRA-PEREZ Grupo de Investigacion en Ingenieria Aeroespacial Universidad Pontificia BolivarianaCircular 170-01Medellin 050031Colombia

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) *** 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%.

关键词： Clustering DBSCAN factor analysis FBGs Pattern recognition Strain field

analysis of inhomogeneity of solidified microstructure of continuous casting copper tubular billet based on factor analysis

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China Foundry 2023年第6期20卷 526-536页

作者： Jin-song Liu Chao-rui Shan Da-yong Chen Hong-wu Song Chuan-lai Chen Yun-yue Chen School of Materials Science and Engineering Shenyang Ligong UniversityShenyang 110159China Shi-Changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Changzhou Enreach Copper Co. Ltd.Changzhou 213149JiangsuChina

The horizontal continuous casting process,the initial step in TP2 copper tubular processing,directly determines the microstructure and properties of copper ***,the process parameters of the continuous casting characterize time variation,multiple disturbances and strong *** a consequence,their influence on a casting billet is difficult to be *** 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 *** multiple process parameters were studied and classified using common factor analysis,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 *** 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 *** 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.

关键词： TP2 copper tubular billet horizontal continuous casting factor analysis microstructure inhomogeneity of casting billet quality diagnosis

Max-margin non-negative matrix factorization with flexible spatial constraints based on factor analysis

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Frontiers of Computer Science 2016年第2期10卷 302-316页

作者： Dakun LIU Xiaoyang TAN Department of Computer Science and Engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 China

Non-negative matrix factorization （NMF） is a popular feature encoding method for image understanding due to its non-negative properties in representation, but the learnt basis images are not always local due to the lack of explicit constraints in its objective. Various algebraic or geometric local constraints are hence proposed to shape the behaviour of the original NMF. Such constraints are usually rigid in the sense that they have to be specified beforehand instead of learning from the data. In this paper, we propose a flexible spatial constraint method for NMF learning based on factor analysis. Particularly, to learn the local spatial structure of the images, we apply a series of transformations such as orthogonal rotation and thresholding to the factor loading matrix obtained through factor analysis. Then we map the transformed loading matrix into a Laplacian matrix and incorporate this into a max-margin non-negative matrix factorization framework as a penalty term, aiming to learn a representation space which is non-negative, discriminative and localstructure-preserving. We verify the feasibility and effectiveness of the proposed method on several real world datasets with encouraging results.

关键词： non-negative matrix factorization factor analysis loading matrix flexible spatial constraints

analysis of factors influencing the Henry Hub natural gas price based on factor analysis

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Petroleum Science 2017年第4期14卷 822-830页

作者： Hong Li Hui-Ming Zhang Yuan-Tao Xie Di Wang School of Economics Peking UniversityBeijing 100871People's Republic of China Center for National Resource Economy Studies Beijing 100871People's Republic of China School of Insurance and Economics University of International Business and EconomicsBeijing 100029People's Republic of China

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.

关键词： Natural gas Henry Hub factor analysis

Using Sieve of Eratosthenes for the factor analysis of Neutrosophic Form of the Five Facet Mindfulness Questionnaire as an Alternative Confirmatory factor analysis

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Computer Modeling in Engineering & Sciences 2021年第11期129卷 953-971页

作者： Volkan Duran Selcuk Topal Florentin Smarandache Said Broumi Igdır University CampusIgdır76000Turkey Department of Mathematics Arts and Sciences FacultyBitlis Eren UniversityBitlisTurkey Department of Mathematics University of New MexicoGallup87301NMUSA Laboratory of Information Processing Faculty of Science Ben M’SikUniversity Hassan IICasablancaMorocco

In this study,the Five Facet Mindfulness Questionnaire which was adapted from the short form of the Five Facet Mindfulness Questionnaire was evaluated and this scale into neutrosophic form was converted and the results of the scale were compared for proposing new type confirmatory analysis procedure as well as developing neutrosophic *** exploratory factor analysis was used in the analysis of the ***,test results were analyzed for Kaiser–Meyer–Olkin and Bartlett values,common factor variance values,scree plot graphs,and the principal component analysis *** sample of the study consists of 194 students in mathematics departments at Bitlis Eren University and Igdır University in Turkey by convenience sampling method.A convenience sampling is a kind˘of non-probability sampling procedure in which the sample is obtained from a group of individuals easily accessible or *** convenience sampling method was chosen in this study because the study aims to examine the structure of the measurement tool rather than the psychological characteristics of a particular *** of all,it is observed that if any classical scale can be converted into a neutrosophic *** is observed that the sub-dimensions of a neutrosophic scale as agree,disagree,and undecided might not have a similar factor structure to the classical ***,in the factor analysis of the neutrosophic scale,both classical and the agreement part of the neutrosophic scales have the same factors,implying that the one-dimensional classical scale measures the agreement degree of the *** the factor analysis was conducted to disagreement and vagueness dimensions,it seemed that some factors were eliminated and even some new factors emerged,indicating that in human cognition those three dimensions can be taken as independent of each other,just as assumed by neutrosophic *** another important implication of the factor analysis is that the neutrosophic forms

关键词： Neutrosophic scales factor analysis scale development explanatory analysis reliability analysis

Measuring speed consistency for freeway diverge areas using factor analysis

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Journal of Central South University 2013年第1期20卷 267-273页

作者：曲栩郭唐仪王炜胡启洲 School of Transportation Southeast University School of Automation Nanjing University of Science and Technology

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.

关键词： safety freeway speed consistency factor analysis

Modeling Indicator Systems for Evaluating Environmental Sustainable Development Based on factor analysis

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Wuhan University Journal of Natural Sciences 2006年第4期11卷 997-1002页

作者： WU Hao CHEN Xiaoling HE Ying HE Xiaorong CAI Xiaobin XU Keya State Key Laboratory of Information Engineering in Surveying Mapping and Remote Sensing Wuhan University Wuhan 430079 HubeiChina School of Resources and Environmental Engineering Wuhan University of Technology Wuhan 430070 Hubei China Shanghai Lake Tai Basin Projects Management Office Shanghai Water Authority Shanghai 200003 China

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 *** 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.

关键词： factor analysis the Poyang Lake Basin environment evaluation sustainable development indicator systems

Modeling parameters influencing city gas distribution sector based on factor analysis method

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Petroleum Research 2022年第1期7卷 144-154页

作者： Kriti Yadav Anirbid Sircar Centre of Excellence for Geothermal Energy Pandit Deendayal Petroleum UniversityRaisanGandhinagarIndia

City gas distribution(CGD)sector is influenced by several factors like policy,infrastructure,health,safety *** order to understand this sector,an exploratory factor analysis is *** Exploratory factor analysis(EFA)survey meticulously simplifies interconnected steps and examines the possible causal factor structure of a series of measured variables without hitting a predetermined result *** this paper,the factor analysis is performed in three broad categories namely:managerial level,technical level and site workers to understand the most influencing factor of the sector.60 questionnaires were prepared to get feedback on parameters affecting CGD *** survey is performed by various means,like google form,email,phone calls,appointments with employees and personal *** has been observed from the survey that the nine factors influences this sector and requires certain modifications for the *** of these nine factors,five were selected for the analysis which are infrastructure factor,policy factor,gas consumption factor,total energy demand factor and economy *** factor analysis has been performed in five major steps,namely factor analysis applicability,selection of factors,loading of factors,significance test of factors and factor loading matrix *** results obtained from these exploratory factor analysis shows that variables like infrastructure,total energy demand and economy affects the CGD market most than the policy and gas consumption.

关键词： City gas distribution factor analysis Exploratory factor analysis Variables Natural gas

factor analysis identifies subgroups of constipation

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World Journal of Gastroenterology 2011年第11期17卷 1468-1474页

作者： Philip G Dinning Mike Jones Linda Hunt Sergio E Fuentealba Jamshid Kalanter Denis W King David Z Lubowski Nicholas J Talley Ian J Cook Department of Gastroenterology St.George HospitalUniversity of New South WalesKogarahNSW 2217Australia Department of Psychology Macquarie UniversityNSW 2109Australia Gastroenterology Research Unit Nepean HospitalUniversity of SydneySydneyNSW 2050Australia Department of Colorecta Surgery St.George HospitalKogarahNSW 2217Australia Gastroenterology and Hepatology Mayo ClinicJacksonvilleFL 32224United States

AIM:To determine whether distinct symptom groupings exist in a constipated population and whether such grouping might correlate with quantifiable pathophysiological measures of colonic ***: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 *** hundred of these patients had colonic transit measured *** analysis determined whether constipation-related symptoms grouped into distinct aspects of *** analysis was used to determine whether indi-vidual patients naturally group into distinct ***:Cluster analysis yielded a 4 cluster solution with the presence or absence of pain and laxative unresponsiveness providing the main *** all clusters there was a considerable proportion of patients with demonstrable delayed colon transit,irritable bowel syndrome positive criteria and regular stool *** majority of patients with these characteristics also reported regular laxative ***:factor analysis identified four constipation subgroups,based on severity and laxative unresponsiveness,in a constipated ***,clear stratification into clinically identifiable groups remains imprecise.

关键词： factor analysis Constipation Symptoms Clusters Laxatives

Quantum Biophysics of the Atmosphere: factor analysis of the Annual Dynamics of Maximum, Minimum and Average Temperatures from 1879 to 2017 to Hadley English Temperature Center (Hadcet)

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Journal of Environmental & Earth Sciences 2021年第1期3卷 29-40页

作者： Mazurkin Peter Matveevich Volga State Technological University Russian Federation

factor analysis of annual dynamics from 1879 to 2017 was carried out by the method of identification of stable regularities:maximum,minimum and average air temperature of Central England according to *** sample capacity was 139 *** factor analysis,time is excluded,and it acts only as a system-forming factor that ensures the relationship between the three parameters of climate and ***,the adequacy of the dynamics models is taken into account in the diagonal cells of the correlation *** addition to time,different lists of objects are possible in factor *** coefficient of correlation variation,that is,a measure of the functional relationship between the parameters of the system(annual weather at the weather station in Central England)is 0.8230 for trends,0.8603 taking into account the annual dynamics of the four-membered model obtained from the computational capabilities of the software environment CurveExpert-1.40,and 0.9578 for the full up to the error of measurement wavelet analysis of the dynamics of the values of three *** all three methods of factor analysis,the meteorological parameter«average Annual temperature»was in the first place as the influencing variable,the«Maximum temperature»was in the second place,and the«Minimum temperature»was in the third *** the dependent measure in these areas there are three kinds of *** comparison shows that among the binary relations between the three temperatures,the average temperature on the maximum air temperature in the surface layer of the atmosphere has the greatest influence on the correlation coefficient *** the same time,all six equations refer to strong connections,so there is a high quantum certainty between the three types of *** when predicting the most meaningful essence showed the maximum temperature.

关键词： Central England Annual temperatures Dynamics from 1879 to 2017 Binary relations factor analysis Behavior quanta