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Principals’and Teachers’Awareness,Knowledge,and Differentiation of Privatization-A Secondary Publication
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作者 Masaaki Katsuno 《Journal of Contemporary Educational Research》 2024年第2期183-186,共4页
Based on the keynote report by Professor Martin Thrupp,this paper discusses the hollowing out of education provision by the state and the permeation of managerialism.It was pointed out that principals and boards of tr... Based on the keynote report by Professor Martin Thrupp,this paper discusses the hollowing out of education provision by the state and the permeation of managerialism.It was pointed out that principals and boards of trustees in socioeconomically advantaged areas may not be willing to share their benefits with schools in less advantaged areas.The new liberal policies have hollowed out state provision of education,so the education system has come to rely heavily on private actors.This paper also presents the current stage of privatization in Japan and the principals’and teachers’perceptions of privatization. 展开更多
关键词 PRIVATIZATION Education principals and teachers
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The Principals Stress and Coping Strategies in Bedouin Schools in Israel
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作者 Sleiman Aburkayek 《Chinese Business Review》 2022年第3期91-101,共11页
The purpose of this research is to investigate the principals’stress and coping strategies to deal with stress by principals in Bedouin schools in Israel.Data were collected in this research by combining a quantitati... The purpose of this research is to investigate the principals’stress and coping strategies to deal with stress by principals in Bedouin schools in Israel.Data were collected in this research by combining a quantitative and qualitative mixed method.A quantitative research questionnaire was conducted for school principals in 36 schools,in addition to an interview with three principals based on the causes of principal stress and coping mechanisms.Research results show that the principals experiencing balance had the highest mean(M)of 3.28 and standard deviation(SD)of 1.64 on a five-point scale.Principals experiencing moderate stress was parents(M=3.10,SD=0.57)and teachers(M=3.14,SD=0.54),while workload had the lowest mean(M=2.97,SD=0.64). 展开更多
关键词 BEDOUIN STRESS principals’stress BURNOUT coping strategies
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Place and Belonging: How Rural Primary School Principals can Promote Boarders’ Development by Building their Sense of Belonging to School?
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作者 Dan Cheng 《Journal of Educational Theory and Management》 2021年第2期77-84,共8页
Rural boarding schools in compulsory education in China have proliferated with school merger program.This paper analyzes the relationship between school belonging and student development and the factors that influence... Rural boarding schools in compulsory education in China have proliferated with school merger program.This paper analyzes the relationship between school belonging and student development and the factors that influence students'sense of belonging in rural boarding schools.The paper examines how principals in rural boarding schools in China can promote student development by building a sense of belonging.The paper argues that building this sense of belonging can serve as a solution to the current problems affecting rural boarding schools,improve the quality of rural primary education,and promote student development. 展开更多
关键词 Rural borders Sense of belonging to school principals Students’development
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Photobiomodulation inhibits the expression of chondroitin sulfate proteoglycans after spinal cord injury via the Sox9 pathway 被引量:1
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作者 Zhihao Zhang Zhiwen Song +12 位作者 Liang Luo Zhijie Zhu Xiaoshuang Zuo Cheng Ju Xuankang Wang Yangguang Ma Tingyu Wu Zhou Yao Jie Zhou Beiyu Chen Tan Ding Zhe Wang Xueyu Hu 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第1期180-189,共10页
Both glial cells and glia scar greatly affect the development of spinal cord injury and have become hot spots in research on spinal cord injury treatment.The cellular deposition of dense extracellular matrix proteins ... Both glial cells and glia scar greatly affect the development of spinal cord injury and have become hot spots in research on spinal cord injury treatment.The cellular deposition of dense extracellular matrix proteins such as chondroitin sulfate proteoglycans inside and around the glial scar is known to affect axonal growth and be a major obstacle to autogenous repair.These proteins are thus candidate targets for spinal cord injury therapy.Our previous studies demonstrated that 810 nm photo biomodulation inhibited the formation of chondroitin sulfate proteoglycans after spinal cord injury and greatly improved motor function in model animals.However,the specific mechanism and potential targets involved remain to be clarified.In this study,to investigate the therapeutic effect of photo biomodulation,we established a mouse model of spinal cord injury by T9 clamping and irradiated the injury site at a power density of 50 mW/cm~2 for 50 minutes once a day for 7 consecutive days.We found that photobiomodulation greatly restored motor function in mice and down regulated chondroitin sulfate proteoglycan expression in the injured spinal cord.Bioinformatics analysis revealed that photobiomodulation inhibited the expression of proteoglycan-related genes induced by spinal cord injury,and versican,a type of proteoglycan,was one of the most markedly changed molecules.Immunofluorescence staining showed that after spinal cord injury,versican was present in astrocytes in spinal cord tissue.The expression of versican in primary astrocytes cultured in vitro increased after inflammation induction,whereas photobiomodulation inhibited the expression of ve rsican.Furthermore,we found that the increased levels of p-Smad3,p-P38 and p-Erk in inflammatory astrocytes were reduced after photobiomodulation treatment and after delivery of inhibitors including FR 180204,(E)-SIS3,and SB 202190.This suggests that Sma d 3/Sox9 and MAP K/Sox9 pathways may be involved in the effects of photobiomodulation.In summary,our findings show that photobiomodulation modulates the expression of chondroitin sulfate proteoglycans,and versican is one of the key target molecules of photo biomodulation.MAPK/Sox9 and Smad3/Sox9 pathways may play a role in the effects of photo biomodulation on chondroitin sulfate proteoglycan accumulation after spinal cord injury. 展开更多
关键词 chondroitin sulfate proteoglycans Erk MAPK P38 PHOTOBIOMODULATION principal component analysis SMAD3 SOX9 spinal cord injury VERSICAN
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Systemic modulation of skeletal mineralization by magnesium implant promoting fracture healing: Radiological exploration enhanced with PCA-based machine learning in a rat femoral model
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作者 Yu Sun Heike Helmholz Regine Willumeit-Römer 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第3期1009-1020,共12页
The clinical application of magnesium(Mg)and its alloys for bone fractures has been well supported by in vitro and in vivo trials.However,there were studies indicating negative effects of high dose Mg intake and susta... The clinical application of magnesium(Mg)and its alloys for bone fractures has been well supported by in vitro and in vivo trials.However,there were studies indicating negative effects of high dose Mg intake and sustained local release of Mg ions on bone metabolism or repair,which should not be ignored when developing Mg-based implants.Thus,it remains necessary to assess the biological effects of Mg implants in animal models relevant to clinical treatment modalities.The primary purpose of this study was to validate the beneficial effects of intramedullary Mg implants on the healing outcome of femoral fractures in a modified rat model.In addition,the mineralization parameters at multiple anatomical sites were evaluated,to investigate their association with healing outcome and potential clinical applications.Compared to the control group without Mg implantation,postoperative imaging at week 12 demonstrated better healing outcomes in the Mg group,with more stable unions in 3D analysis and high-mineralized bridging in 2D evaluation.The bone tissue mineral density(TMD)was higher in the Mg group at the non-operated femur and lumbar vertebra,while no differences between groups were identified regarding the bone tissue volume(TV),TMD and bone mineral content(BMC)in humerus.In the surgical femur,the Mg group presented higher TMD,but lower TV and BMC in the distal metaphyseal region,as well as reduced BMC at the osteotomy site.Principal component analysis(PCA)-based machine learning revealed that by selecting clinically relevant parameters,radiological markers could be constructed for differentiation of healing outcomes,with better performance than 2D scoring.The study provides insights and preclinical evidence for the rational investigation of bioactive materials,the identification of potential adverse effects,and the promotion of diagnostic capabilities for fracture healing. 展开更多
关键词 MAGNESIUM Implants Bone fracture MINERALIZATION Systemic modulation Principal component analysis.
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Three-dimensional stress variation characteristics in deep hard rock of CJPL-Ⅱ project based on in-situ monitoring
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作者 Minzong Zheng Shaojun Li +2 位作者 Zejie Feng Huaisheng Xu Yaxun Xiao 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第2期179-195,共17页
In deep hard rock excavation, stress plays a pivotal role in inducing stress-controlled failure. While the impact of excavation-induced stress disturbance on rock failure and tunnel stability has undergone comprehensi... In deep hard rock excavation, stress plays a pivotal role in inducing stress-controlled failure. While the impact of excavation-induced stress disturbance on rock failure and tunnel stability has undergone comprehensive examination through laboratory tests and numerical simulations, its validation through insitu stress tests remains unexplored. This study analyzes the three-dimensional stress changes in the surrounding rock at various depths, monitored during the excavation of B2 Lab in China Jinping Underground Laboratory Phase Ⅱ(CJPL-Ⅱ). The investigation delves into the three-dimensional stress variation characteristics in deep hard rock, encompassing stress components and principal stress. The results indicate changes in both the magnitude and direction of the principal stress during tunnel excavation. To quantitatively describe the degree of stress disturbance, a series of stress evaluation indexes are established based on the distances between stress tensors, including the stress disturbance index(SDI), the principal stress magnitude disturbance index(SDIm), and the principal stress direction disturbance index(SDId). The SDI indicates the greatest stress disturbance in the surrounding rock is 4.5 m from the tunnel wall in B2 Lab. SDIm shows that the principal stress magnitude disturbance peaks at2.5 m from the tunnel wall. SDId reveals that the largest change in principal stress direction does not necessarily occur near the tunnel wall but at a specific depth from it. The established relationship between SDI and the depth of the excavation damaged zone(EDZ) can serve as a criterion for determining the depth of the EDZ in deep hard rock engineering. Additionally, it provides a reference for future construction and support considerations. 展开更多
关键词 Disturbance stress Tensor distance Stress disturbance index Principal stress direction Underground research laboratory
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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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Regulation effects of water and nitrogen on yield,water,and nitrogen use efficiency of wolfberry
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作者 GAO Yalin QI Guangping +7 位作者 MA Yanlin YIN Minhua WANG Jinghai WANG Chen TIAN Rongrong XIAO Feng LU Qiang WANG Jianjun 《Journal of Arid Land》 SCIE CSCD 2024年第1期29-45,共17页
Wolfberry(Lycium barbarum L.)is important for health care and ecological protection.However,it faces problems of low productivity and resource utilization during planting.Exploring reasonable models for water and nitr... Wolfberry(Lycium barbarum L.)is important for health care and ecological protection.However,it faces problems of low productivity and resource utilization during planting.Exploring reasonable models for water and nitrogen management is important for solving these problems.Based on field trials in 2021 and 2022,this study analyzed the effects of controlling soil water and nitrogen application levels on wolfberry height,stem diameter,crown width,yield,and water(WUE)and nitrogen use efficiency(NUE).The upper and lower limits of soil water were controlled by the percentage of soil water content to field water capacity(θ_(f)),and four water levels,i.e.,adequate irrigation(W0,75%-85%θ_(f)),mild water deficit(W1,65%-75%θ_(f)),moderate water deficit(W2,55%-65%θ_(f)),and severe water deficit(W3,45%-55%θ_(f))were used,and three nitrogen application levels,i.e.,no nitrogen(N0,0 kg/hm^(2)),low nitrogen(N1,150 kg/hm^(2)),medium nitrogen(N2,300 kg/hm^(2)),and high nitrogen(N3,450 kg/hm^(2))were implied.The results showed that irrigation and nitrogen application significantly affected plant height,stem diameter,and crown width of wolfberry at different growth stages(P<0.01),and their maximum values were observed in W1N2,W0N2,and W1N3 treatments.Dry weight per plant and yield of wolfberry first increased and then decreased with increasing nitrogen application under the same water treatment.Dry weight per hundred grains and dry weight percentage increased with increasing nitrogen application under W0 treatment.However,under other water treatments,the values first increased and then decreased with increasing nitrogen application.Yield and its component of wolfberry first increased and then decreased as water deficit increased under the same nitrogen treatment.Irrigation water use efficiency(IWUE,8.46 kg/(hm^(2)·mm)),WUE(6.83 kg/(hm^(2)·mm)),partial factor productivity of nitrogen(PFPN,2.56 kg/kg),and NUE(14.29 kg/kg)reached their highest values in W2N2,W1N2,W1N2,and W1N1 treatments.Results of principal component analysis(PCA)showed that yield,WUE,and NUE were better in W1N2 treatment,making it a suitable water and nitrogen management mode for the irrigation area of the Yellow River in the Gansu Province,China and similar planting areas. 展开更多
关键词 water deficit growth characteristics YIELD water and nitrogen use efficiency principal component analysis
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PCA-LSTM:An Impulsive Ground-Shaking Identification Method Based on Combined Deep Learning
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作者 Yizhao Wang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第6期3029-3045,共17页
Near-fault impulsive ground-shaking is highly destructive to engineering structures,so its accurate identification ground-shaking is a top priority in the engineering field.However,due to the lack of a comprehensive c... Near-fault impulsive ground-shaking is highly destructive to engineering structures,so its accurate identification ground-shaking is a top priority in the engineering field.However,due to the lack of a comprehensive consideration of the ground-shaking characteristics in traditional methods,the generalization and accuracy of the identification process are low.To address these problems,an impulsive ground-shaking identification method combined with deep learning named PCA-LSTM is proposed.Firstly,ground-shaking characteristics were analyzed and groundshaking the data was annotated using Baker’smethod.Secondly,the Principal Component Analysis(PCA)method was used to extract the most relevant features related to impulsive ground-shaking.Thirdly,a Long Short-Term Memory network(LSTM)was constructed,and the extracted features were used as the input for training.Finally,the identification results for the Artificial Neural Network(ANN),Convolutional Neural Network(CNN),LSTM,and PCA-LSTMmodels were compared and analyzed.The experimental results showed that the proposed method improved the accuracy of pulsed ground-shaking identification by>8.358%and identification speed by>26.168%,compared to other benchmark models ground-shaking. 展开更多
关键词 Impulsive ground-shaking principal component analysis artificial intelligence deep learning impulse recognition
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Identifying Brand Consistency by Product Differentiation Using CNN
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作者 Hung-Hsiang Wang Chih-Ping Chen 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第7期685-709,共25页
This paper presents a new method of using a convolutional neural network(CNN)in machine learning to identify brand consistency by product appearance variation.In Experiment 1,we collected fifty mouse devices from the ... This paper presents a new method of using a convolutional neural network(CNN)in machine learning to identify brand consistency by product appearance variation.In Experiment 1,we collected fifty mouse devices from the past thirty-five years from a renowned company to build a dataset consisting of product pictures with pre-defined design features of their appearance and functions.Results show that it is a challenge to distinguish periods for the subtle evolution of themouse devices with such traditionalmethods as time series analysis and principal component analysis(PCA).In Experiment 2,we applied deep learning to predict the extent to which the product appearance variation ofmouse devices of various brands.The investigation collected 6,042 images ofmouse devices and divided theminto the Early Stage and the Late Stage.Results show the highest accuracy of 81.4%with the CNNmodel,and the evaluation score of brand style consistency is 0.36,implying that the brand consistency score converted by the CNN accuracy rate is not always perfect in the real world.The relationship between product appearance variation,brand style consistency,and evaluation score is beneficial for predicting new product styles and future product style roadmaps.In addition,the CNN heat maps highlight the critical areas of design features of different styles,providing alternative clues related to the blurred boundary.The study provides insights into practical problems for designers,manufacturers,and marketers in product design.It not only contributes to the scientific understanding of design development,but also provides industry professionals with practical tools and methods to improve the design process and maintain brand consistency.Designers can use these techniques to find features that influence brand style.Then,capture these features as innovative design elements and maintain core brand values. 展开更多
关键词 Machine learning product differentiation brand consistency principal component analysis convolutional neural network computer mouse
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Research and Application of a Multi-Field Co-Simulation Data Extraction Method Based on Adaptive Infinitesimal Element
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作者 Changfu Wan Wenqiang Li +2 位作者 Sitong Ling Yingdong Liu Jiahao Chen 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第1期321-348,共28页
Regarding the spatial profile extraction method of a multi-field co-simulation dataset,different extraction directions,locations,and numbers of profileswill greatly affect the representativeness and integrity of data.... Regarding the spatial profile extraction method of a multi-field co-simulation dataset,different extraction directions,locations,and numbers of profileswill greatly affect the representativeness and integrity of data.In this study,a multi-field co-simulation data extractionmethod based on adaptive infinitesimal elements is proposed.Themultifield co-simulation dataset based on related infinitesimal elements is constructed,and the candidate directions of data profile extraction undergo dimension reduction by principal component analysis to determine the direction of data extraction.Based on the fireworks algorithm,the data profile with optimal representativeness is searched adaptively in different data extraction intervals to realize the adaptive calculation of data extraction micro-step length.The multi-field co-simulation data extraction process based on adaptive microelement is established and applied to the data extraction process of the multi-field co-simulation dataset of the sintering furnace.Compared with traditional data extraction methods for multi-field co-simulation,the approximate model constructed by the data extracted from the proposed method has higher construction efficiency.Meanwhile,the relative maximum absolute error,root mean square error,and coefficient of determination of the approximationmodel are better than those of the approximation model constructed by the data extracted from traditional methods,indicating higher accuracy,it is verified that the proposed method demonstrates sound adaptability and extraction efficiency. 展开更多
关键词 Multi-field co-simulation adaptive infinitesimal elements principal component analysis fireworks algorithm sintering furnace simulation
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Using deep neural networks coupled with principal component analysis for ore production forecasting at open-pit mines
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作者 Chengkai Fan Na Zhang +1 位作者 Bei Jiang Wei Victor Liu 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第3期727-740,共14页
Ore production is usually affected by multiple influencing inputs at open-pit mines.Nevertheless,the complex nonlinear relationships between these inputs and ore production remain unclear.This becomes even more challe... Ore production is usually affected by multiple influencing inputs at open-pit mines.Nevertheless,the complex nonlinear relationships between these inputs and ore production remain unclear.This becomes even more challenging when training data(e.g.truck haulage information and weather conditions)are massive.In machine learning(ML)algorithms,deep neural network(DNN)is a superior method for processing nonlinear and massive data by adjusting the amount of neurons and hidden layers.This study adopted DNN to forecast ore production using truck haulage information and weather conditions at open-pit mines as training data.Before the prediction models were built,principal component analysis(PCA)was employed to reduce the data dimensionality and eliminate the multicollinearity among highly correlated input variables.To verify the superiority of DNN,three ANNs containing only one hidden layer and six traditional ML models were established as benchmark models.The DNN model with multiple hidden layers performed better than the ANN models with a single hidden layer.The DNN model outperformed the extensively applied benchmark models in predicting ore production.This can provide engineers and researchers with an accurate method to forecast ore production,which helps make sound budgetary decisions and mine planning at open-pit mines. 展开更多
关键词 Oil sands production Open-pit mining Deep learning Principal component analysis(PCA) Artificial neural network Mining engineering
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Contrast Normalization Strategies in Brain Tumor Imaging:From Preprocessing to Classification
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作者 Samar M.Alqhtani Toufique A.Soomro +3 位作者 Faisal Bin Ubaid Ahmed Ali Muhammad Irfan Abdullah A.Asiri 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第8期1539-1562,共24页
Cancer-related to the nervous system and brain tumors is a leading cause of mortality in various countries.Magnetic resonance imaging(MRI)and computed tomography(CT)are utilized to capture brain images.MRI plays a cru... Cancer-related to the nervous system and brain tumors is a leading cause of mortality in various countries.Magnetic resonance imaging(MRI)and computed tomography(CT)are utilized to capture brain images.MRI plays a crucial role in the diagnosis of brain tumors and the examination of other brain disorders.Typically,manual assessment of MRI images by radiologists or experts is performed to identify brain tumors and abnormalities in the early stages for timely intervention.However,early diagnosis of brain tumors is intricate,necessitating the use of computerized methods.This research introduces an innovative approach for the automated segmentation of brain tumors and a framework for classifying different regions of brain tumors.The proposed methods consist of a pipeline with several stages:preprocessing of brain images with noise removal based on Wiener Filtering,enhancing the brain using Principal Component Analysis(PCA)to obtain well-enhanced images,and then segmenting the region of interest using the Fuzzy C-Means(FCM)clustering technique in the third step.The final step involves classification using the Support Vector Machine(SVM)classifier.The classifier is applied to various types of brain tumors,such as meningioma and pituitary tumors,utilizing the Contrast-Enhanced Magnetic Resonance Imaging(CE-MRI)database.The proposed method demonstrates significantly improved contrast and validates the effectiveness of the classification framework,achieving an average sensitivity of 0.974,specificity of 0.976,accuracy of 0.979,and a Dice Score(DSC)of 0.957.Additionally,this method exhibits a shorter processing time of 0.44 s compared to existing approaches.The performance of this method emphasizes its significance when compared to state-of-the-art methods in terms of sensitivity,specificity,accuracy,and DSC.To enhance the method further in the future,it is feasible to standardize the approach by incorporating a set of classifiers to increase the robustness of the brain classification method. 展开更多
关键词 Brain tumor magnetic resonance imaging principal component analysis fuzzy c-clustering support vector machine
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A Hybrid Optimization Approach of Single Point Incremental Sheet Forming of AISI 316L Stainless Steel Using Grey Relation Analysis Coupled with Principal Component Analysiss
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作者 A Visagan P Ganesh 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第1期160-166,共7页
We investigated the parametric optimization on incremental sheet forming of stainless steel using Grey Relational Analysis(GRA) coupled with Principal Component Analysis(PCA). AISI 316L stainless steel sheets were use... We investigated the parametric optimization on incremental sheet forming of stainless steel using Grey Relational Analysis(GRA) coupled with Principal Component Analysis(PCA). AISI 316L stainless steel sheets were used to develop double wall angle pyramid with aid of tungsten carbide tool. GRA coupled with PCA was used to plan the experiment conditions. Control factors such as Tool Diameter(TD), Step Depth(SD), Bottom Wall Angle(BWA), Feed Rate(FR) and Spindle Speed(SS) on Top Wall Angle(TWA) and Top Wall Angle Surface Roughness(TWASR) have been studied. Wall angle increases with increasing tool diameter due to large contact area between tool and workpiece. As the step depth, feed rate and spindle speed increase,TWASR decreases with increasing tool diameter. As the step depth increasing, the hydrostatic stress is raised causing severe cracks in the deformed surface. Hence it was concluded that the proposed hybrid method was suitable for optimizing the factors and response. 展开更多
关键词 single point incremental forming AISI 316L taguchi grey relation analysis principal component analysis surface roughness scanning electron microscopy
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Exploring well-being disparities between urban and rural areas:A case study in the Stavropol Territory,Russia
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作者 Anastasia CHAPLITSKAYA Wim HEIJMAN Johan van OPHEM 《Regional Sustainability》 2024年第1期80-92,共13页
Rural areas are crucial for a country’s sustainable economy.New strategies are needed to develop rural areas to improve the well-being of rural population and generate new job opportunities.This is especially importa... Rural areas are crucial for a country’s sustainable economy.New strategies are needed to develop rural areas to improve the well-being of rural population and generate new job opportunities.This is especially important in countries where agricultural production accounts for a significant share of the gross product,such as Russia.In this study,we identified the key indicators of satisfaction and differences between rural and urban citizens based on their social,economic,and environmental backgrounds,and determined whether there are well-being disparities between rural and urban areas in the Stavropol Territory,Russia.We collected primary data through a survey based on the European Social Survey framework to investigate the potential differences between rural and urban areas.By computing the regional well-being index using principal component analysis,we found that there was no statistically significant difference in well-being between rural and urban areas.Results of key indicators showed that rural residents felt psychologically more comfortable and safer,assessed their family relationships better,and adhered more to traditions and customs.However,urban residents showed better economic and social conditions(e.g.,infrastructures,medical care,education,and Internet access).The results of this study imply that we can better understand the local needs,advantages,and unique qualities,thereby gaining insight into the effectiveness of government programs.Policy-makers and local authorities can consider targeted interventions based on the findings of this study and strive to enhance the well-being of both urban and rural residents. 展开更多
关键词 WELL-BEING Sustainable development Rural areas Urban areas Principal component analysis(PCA) RUSSIA
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A Modified Principal Component Analysis Method for Honeycomb Sandwich Panel Debonding Recognition Based on Distributed Optical Fiber Sensing Signals
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作者 Shuai Chen Yinwei Ma +5 位作者 Zhongshu Wang Zongmei Xu Song Zhang Jianle Li Hao Xu Zhanjun Wu 《Structural Durability & Health Monitoring》 EI 2024年第2期125-141,共17页
The safety and integrity requirements of aerospace composite structures necessitate real-time health monitoring throughout their service life.To this end,distributed optical fiber sensors utilizing back Rayleigh scatt... The safety and integrity requirements of aerospace composite structures necessitate real-time health monitoring throughout their service life.To this end,distributed optical fiber sensors utilizing back Rayleigh scattering have been extensively deployed in structural health monitoring due to their advantages,such as lightweight and ease of embedding.However,identifying the precise location of damage from the optical fiber signals remains a critical challenge.In this paper,a novel approach which namely Modified Sliding Window Principal Component Analysis(MSWPCA)was proposed to facilitate automatic damage identification and localization via distributed optical fiber sensors.The proposed method is able to extract signal characteristics interfered by measurement noise to improve the accuracy of damage detection.Specifically,we applied the MSWPCA method to monitor and analyze the debonding propagation process in honeycomb sandwich panel structures.Our findings demonstrate that the training model exhibits high precision in detecting the location and size of honeycomb debonding,thereby facilitating reliable and efficient online assessment of the structural health state. 展开更多
关键词 Structural health monitoring distributed opticalfiber sensor damage identification honeycomb sandwich panel principal component analysis
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The Impact of Big Five Personality Traits on Older Europeans’ Physical Health
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作者 Eleni Serafetinidou Christina Parpoula 《Journal of Biomedical Science and Engineering》 2024年第2期41-56,共16页
Investigating the role of Big Five personality traits in relation to various health outcomes has been extensively studied. The impact of “Big Five” on physical health is here explored for older Europeans with a focu... Investigating the role of Big Five personality traits in relation to various health outcomes has been extensively studied. The impact of “Big Five” on physical health is here explored for older Europeans with a focus on examining age groups differences. The study sample included 378,500 respondents derived from the seventh data wave of Survey of Health, Aging and Retirement in Europe (SHARE). The physical health status of older Europeans was estimated by constructing an index considering the combined effect of well-established health indicators such as the number of chronic diseases, mobility limitations, limitations with basic and instrumental activities of daily living, and self-perceived health. This index was used for an overall physical health assessment, for which the higher the score for an individual, the worst health level. Then, through a dichotomization process applied to the retrieved Principal Component Analysis scores, a two-group discrimination (good or bad health status) of SHARE participants was obtained as regards their physical health condition, allowing for further con-structing logistic regression models to assess the predictive significance of “Big Five” and their protective role for physical health. Results showed that neuroti-cism was the most significant predictor of physical health for all age groups un-der consideration, while extraversion, agreeableness and openness were not found to significantly affect the self-reported physical health levels of midlife adults aged 50 up to 64. Older adults aged 65 up to 79 were more prone to open-ness, whereas the oldest old individuals aged 80 up to 105 were mainly affected by openness and conscientiousness. . 展开更多
关键词 Big Five Personality Traits Physical Health Older Europeans SHARE Principal Component Analysis
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Portraits of Principals in Chinese Urban and Rural Schools:A Comparative Analysis
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作者 Zhixin SU Jody DUNLAP +2 位作者 XIA Huixian WANG Jian MAO Dan 《Frontiers of Education in China》 2019年第3期422-452,共31页
This paper reports findings from a comparative study of urban vs.rural school principals in China.It is an extension and replication of an earlier study on the profiles and preparation of school leaders in the US and ... This paper reports findings from a comparative study of urban vs.rural school principals in China.It is an extension and replication of an earlier study on the profiles and preparation of school leaders in the US and China.The study illustrates modern portraits-demographic characteristics of urban and rural principals in China,explores their entry perspectives and examines their professional commitment to principalship as a lifelong career.Findings from the comparative study indicate that urban and rural school principals in China differ greatly in their profiles and characteristics.They share similar intrinsic or extrinsic reasons for becoming principals,but they also vary on some key reasons.Unfortunately,most of the principals in our study are not firmly committed to principalship as a lifelong career because of a range of disturbing factors.Findings from this study shed new light on the profiles and preparation of educational leaders in China and offer thoughtful recommendations for change to both Chinese and international education community. 展开更多
关键词 Chinese education school principals urban education rural education
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Projected Changes in the Climate Zoning of Côte d’Ivoire
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作者 Mamadou Diarrassouba Adama Diawara +6 位作者 Assi Louis Martial Yapo Benjamin Komenan Kouassi Fidèle Yoroba Kouakou Kouadio Dro Touré Tiemoko Dianikoura Ibrahim Koné Arona Diedhiou 《Atmospheric and Climate Sciences》 2024年第1期62-84,共23页
This study assesses the projected changes in the climate zoning of Côte d’Ivoire using the hierarchical classification of principal components (HCPC) method applied to the daily precipitation data of an ensemble... This study assesses the projected changes in the climate zoning of Côte d’Ivoire using the hierarchical classification of principal components (HCPC) method applied to the daily precipitation data of an ensemble of 14 CORDEX-AFRICA simulations under RCP4.5 and RCP8.5 scenarios. The results indicate the existence of three climate zones in Côte d’Ivoire (the coastal, the centre and the north) over the historical period (1981-2005). Moreover, CORDEX simulations project an extension of the surface area of drier climatic zones while a reduction of wetter zones, associated with the appearance of an intermediate climate zone with surface area varying from 77,560 km<sup>2</sup> to 134,960 km<sup>2</sup> depending on the period and the scenario. These results highlight the potential impacts of climate change on the delimitation of the climate zones of Côte d’Ivoire under the greenhouse gas emission scenarios. Thus, there is a reduction in the surface areas suitable for the production of cash crops such as cocoa and coffee. This could hinder the country’s economy and development, mainly based on these cash crops. 展开更多
关键词 Climate Projection Climate Zone Principal Component Analysis Hierarchical Classification on Principal Components CORDEX Côte d’Ivoire
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Values and Actions:An Exploratory Study of School Principals in the Mainland of China
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作者 John R.PISAPIA LIN Ying 《Frontiers of Education in China》 2011年第3期361-387,共27页
This paper explores the relationship between leader values and actions in the Chinese context.The Chinese Value Instrument(CVI)and the Strategic Leadership Questionnaire(SLQ)were used as the primary data collection to... This paper explores the relationship between leader values and actions in the Chinese context.The Chinese Value Instrument(CVI)and the Strategic Leadership Questionnaire(SLQ)were used as the primary data collection tools.The CVI was used to measure the presence of ten values:(1)social harmony,(2)benevolence and honesty,(3)initiative and innovation(challenge and creativity),(4)achievement and power,(5)zhongyong(practicality and modesty),(6)stability,(7)familial loyalty,(8)happiness,(9)renqing(sympathy)and guanxi(personal relationships),and(10)freedom and equity.The findings indicate that achievement and initiative were at the low end of the value continuum.Familial loyalty,social harmony,and benevolence were at the high end of the value continuum.The SLQ measured the managing,transforming,bonding,bridging,and bartering actions leaders use to mobilize and gain support from followers.The findings indicate that the Chinese school principal management prototype is formed around transforming and bonding actions.This prototype changes depending on role assignment and school type.A connection between leader values and actions was established with regard to the values of achievement and power,benevolence and honesty,and stability. 展开更多
关键词 strategic leadership actions value orientations school principals
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