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Internet Gaming Disorder and Mental Health of Children in China:A Latent Profile Analysis
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作者 Md Zahir Ahmed Oli Ahmed +2 位作者 Lingfeng Gao Mary C.Jobe Weijian Li 《International Journal of Mental Health Promotion》 2024年第7期517-529,共13页
In recent years,speculation of an increase in Internet Gaming Disorder(IGD)has surfaced with the growing popularity of internet gaming among Chinese children and adolescents.The detrimental impact of IGD on mental hea... In recent years,speculation of an increase in Internet Gaming Disorder(IGD)has surfaced with the growing popularity of internet gaming among Chinese children and adolescents.The detrimental impact of IGD on mental health cannot be denied,even though only a small portion of the screen-dependent population exhibits psychopathological and behavioral symptoms.The present study aimed to explore a latent profile analysis(LPA)of Internet Gaming Disorder on the mental health of Chinese school students.The data were collected from a sample of 1005 Chinese school students(49.8%male;age M=13.32,SD=1.34 years)using a paper-pencil survey through convenience sampling.LPA explored three latent profiles of internet gamers:regular gamers(62.4%),moderate gamers(28.1%),and probable disordered gamers(9.4%).Results showed that the probable disordered gamers had significantly higher levels of depression,anxiety,emotional and conduct problems,hyperactivity,and peer problem symptoms as well as lower life satisfaction,and pro-social symptoms compared to regular and moderate gamers(p<0.05).This study would be helpful to mental health professionals in designing interventions for gamers who present IGD symptoms.Future longitudinal studies should also be undertaken to assess whether mental health worsens for probable disordered gamers. 展开更多
关键词 Internet gaming disorder latent profile analysis mental health children and adolescents China
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Current Status of Key Competencies among Medical Students: A Latent Profile Analysis
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作者 Mengyao Xiao Li Yan +1 位作者 Yongping Xia Li Liu 《Open Journal of Applied Sciences》 2024年第2期450-465,共16页
The purpose of this study was to understand the overall level of key competencies of medical students and explore the potential profile of key competencies, promoting quality education, and improving the quality talen... The purpose of this study was to understand the overall level of key competencies of medical students and explore the potential profile of key competencies, promoting quality education, and improving the quality talent cultivation in medical colleges. A stratified random sampling method selected 734 medical students from four medical colleges in Chongqing Province of China. A general information questionnaire and a key competencies survey questionnaire were used to conduct the survey. The overall score and scores of each dimension of key competencies were analyzed. Latent profile analysis was conducted to classify the key competencies of medical students and compare the distribution differences of demographic variables among different categories. The results showed that 26% of medical students have never heard of the concept of key competencies, and 59% of them are not familiar with the content related to key competencies. The score of key competencies is 3.66 ± 0.60, with the highest score in the dimension of responsibility and the lowest score in the dimension of humanistic accomplishment. The latent profile analysis classified them into three categories: “low key competencies group (14.71%)”, “medium key competencies group (36.79%)”, and “high key competencies group (48.50%)”. The R3STEP regression analysis results showed statistically significant differences in educational level and whether they served as student cadres among different key competencies categories of medical students. This paper discusses three different potential key competencies categories among medical students, and the overall level of key competencies is relatively good. However, medical students lack a comprehensive and systematic understanding of key competencies. Humanistic accomplishment, healthy living, and practical innovation are the three dimensions with lower scores and should be given more attention. Medical colleges should integrate the concept of key competencies into teaching and implement it in medical practice to cultivate more high-quality medical talents for society. 展开更多
关键词 Sustainable Education Medical Students Key Competencies latent Profile analysis
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Latent profile analysis of perceived stress and influencing factors in colorectal cancer patients
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作者 Yu-Yue Tan Yin-Hong Liu +3 位作者 Zhi-Hui Zhang Wei-Rong Huang Man-Lin Yan Xian-Rong Li 《Frontiers of Nursing》 2024年第3期303-312,共10页
Objective:To understand the latent categories of perceived stress in colorectal cancer patients and analyze the characteristics of different categories of patients.Methods:A total of 255 colorectal cancer patients rec... Objective:To understand the latent categories of perceived stress in colorectal cancer patients and analyze the characteristics of different categories of patients.Methods:A total of 255 colorectal cancer patients receiving treatment in the gastrointestinal surgery and oncology depar tments of a ter tiary Grade A hospital in Sichuan Province,from January 2023 to June 2023,were selected as the study subjects.General information questionnaire,Chinese version of the Perceived Stress Scale(CPSS),and Comprehensive Score Table for Patient-Repor ted Outcome Measures of Economic Toxicity(COST-PROM)were used for data collection.Results:Perceived stress in colorectal cancer patients was classified into 3 latent categories:C1“Low stress-stable type”(19.2%),C2“Moderate stress-uncontrolled type”(23.9%),and C3“High stress-anxious type”(56.9%).The average score of perceived stress was(34.07±5.08).Compared with C1 type,patients with a monthly household income of≤3000 RMB were more likely to belong to the C2 and C3 types(P<0.05),and patients without a stoma were less likely to belong to C3 type(P<0.05).Compared with C2 type,male patients were more likely to belong to C3 type(P<0.05),and patients without a stoma were less likely to belong to C3 type(P<0.05).Compared with C3 type,patients with higher economic toxicity scores were more likely to be classified into C1 and C2 types(P<0.05).Conclusions:Perceived stress in colorectal cancer patients exhibits distinct categorical features.Male gender,lower income,presence of a stoma,and higher economic toxicity are associated with higher levels of perceived stress in colorectal cancer patients. 展开更多
关键词 colorectal cancer economic toxicity influence factors latent profile analysis perceived stress
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Prevalence of Latent Tuberculosis Infection [LTBI] in Prison Officers: A Systematic Review and Meta-Analysis
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作者 Thiago Poss Moreira Gustavo Henrique Baraca Sanvezzo +5 位作者 Maico Trevisol Renan William Mesquita Luiza Scalcon de Oliveira Lia Beatriz Henke de Azevedo Cleide Viviane Buzanello Martins Lirane Elize Defante Ferreto 《Open Journal of Respiratory Diseases》 2024年第1期12-24,共13页
This study aimed to perform a systematic review and meta-analysis to determine the LTBI prevalence in prison officers worldwide. A systematic search was performed in PubMed, WoS, Embase, and BVS, including all article... This study aimed to perform a systematic review and meta-analysis to determine the LTBI prevalence in prison officers worldwide. A systematic search was performed in PubMed, WoS, Embase, and BVS, including all articles related to LTBI prevalence and risk factors. After critical evaluation and qualitative synthesis of the identified articles, a meta-analysis was used. Five studies carried out between 2012 and 2022 were included, with a total sample size of 1718 prison officers. The overall LTBI prevalence was 50% [95% confidence interval [CI]: 48% - 52%;n = 816], with high heterogeneity between studies. Smoking [OR = 1.76;CI 95% = 1.26 - 2.46] and males [OR = 2.08;CI 95% = 1.31 - 3.31] were positively related to a higher LTBI prevalence among prison officers. Thus, preventive measures and the rapid and accurate diagnosis of new cases should be emphasized to ensure tuberculosis control, especially among risk groups such as prison officers. 展开更多
关键词 latent Tuberculosis Mycobacterium tuberculosis META-analysis PREVALENCE Occupational Exposure
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Body Weight Misperception and Weight Disorders among Chinese Children and Adolescents:A Latent Class Analysis 被引量:3
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作者 Ting-ting QIN Huang-guo XIONG +3 位作者 Ming-ming YAN Tong SUN Ling QIAN Ping YIN 《Current Medical Science》 SCIE CAS 2019年第5期852-862,共11页
Body misperception plays an important role in the development of weight and dietary disorders among children and adolescents.A school-based health promotion program(2014-2015)was conducted to promote the school health... Body misperception plays an important role in the development of weight and dietary disorders among children and adolescents.A school-based health promotion program(2014-2015)was conducted to promote the school health education and improve the teenagers'physical health among Chinese children and adolescents.Based on this program,we intended to examine weight status and weight misperception among Chinese children and adolescents and to explore the relationship between weight misperception and lifestyle behaviors.A total of 10708 Chinese children and adolescents in 3rd and 7th grade from Shandong and Qinghai province participated in the program.The participants,dietary and activity patterns were clustered by latent class analysis(LCA).Logistic regression analysis was undertaken to explore the relationship between weight perception and demographic factors or dietary and activity patterns.Given the gender-specific difference of children and adolescents,analyses were separately conducted among boys and girls.The total prevalence of weight misperception was 44.50%.Boys,especially those in higher grade and living in wealthier district,were more likely to misperceive body weight.Girls were more likely to overestimate their weight(26.10%)while boys tended to underestimate the weight(28.32%).Three latent dietary and activity patterns including obesogenic pattern,malnourished pattern and healthy pattern were derived.The participants who had weight misperception were more likely to choose unhealthy dietary and exercise activities.The high prevalence of weight misperception was closely related to the unhealthy weight pattern and unhealthy dietary or exercise patterns.Our research found that most children and adolescents failed to perceive their weight correctly and boys tended to underestimate their weight while girls were subjected to overestimation.So,comprehensive intervention programs should focus on improving self-weight awareness,and appropriate guidance should be made to lead the adolescents to more healthy weight pattern. 展开更多
关键词 WEIGHT perception children and adolescents obesity LIFESTYLE behavior pattern latent class analysis
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Accounting for Heterogeneity in Stop Frequency Models of Work Tours Using Latent Class Poisson Models
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作者 Babak Mirzazadeh 《Journal of Transportation Technologies》 2023年第2期243-261,共19页
Stop frequency models, as one of the elements of activity based models, represent an important part of travel behavior. Unobserved heterogeneity across the travelers should be taken into consideration to prevent biase... Stop frequency models, as one of the elements of activity based models, represent an important part of travel behavior. Unobserved heterogeneity across the travelers should be taken into consideration to prevent biasedness and inconsistency in the estimated parameters in the stop frequency models. Additionally, previous studies on the stop frequency have mostly been done in larger metropolitan areas and less attention has been paid to the areas with less population. This study addresses these gaps by using 2012 travel data from a medium sized U.S. urban area using the work tour for the case study. Stop in the work tour were classified into three groups of outbound leg, work based subtour, and inbound leg of the commutes. Latent Class Poisson Regression Models were used to analyze the data. The results indicate the presence of heterogeneity across the commuters. Using latent class models significantly improves the predictive power of the models compared to regular one class Poisson regression models. In contrast to one class Poisson models, gender becomes insignificant in predicting the number of tours when unobserved heterogeneity is accounted for. The commuters are associated with increased stops on their work based subtour when the employment density of service-related occupations increases in their work zone, but employment density of retail employment does not significantly contribute to the stop making likelihood of the commuters. Additionally, an increase in the number of work tours was associated with fewer stops on the inbound leg of the commute. The results of this study suggest the consideration of unobserved heterogeneity in the stop frequency models and help transportation agencies and policy makers make better inferences from such models. 展开更多
关键词 Activity Based Model Work Tour Stop Frequency latent class Poisson Regression Model
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The Driving Strategy of Online Ideological and Political Class in Universities Based on SWOT Analysis
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作者 Zhuli Feng 《Open Journal of Applied Sciences》 2023年第8期1433-1439,共7页
The epidemic provided practical opportunities for online classes and also tested its drawbacks. To analyze the internal strengths (S) and weaknesses (W) as well as the external opportunities (O) and threats (T) of the... The epidemic provided practical opportunities for online classes and also tested its drawbacks. To analyze the internal strengths (S) and weaknesses (W) as well as the external opportunities (O) and threats (T) of the online ideological and political class with SWOT theory, based on which to explore targeted solutions, is a “symptomatic” approach to improving the quality of the online ideological and political class. The analysis results are as follows: S includes “not limited by time and space”, “comprehensive teaching monitoring data”, “diverse and innovative interactive forms”, and “abundant high-quality teaching resources”. W refers to “increased difficulty in classroom control”, “teachers’ psychological pressure caused by online teaching”, and “limited by hardware conditions”. O means the opportunity provided by the modernization of ideological and political education and epidemics. T indicates external threats, such as limitations from the network and the severe impact of wrong values on the internet. The driving strategy for above case could be “upgrading of online teaching platforms”, “building a teaching team skilled in information technology teaching”, “improving hardware facilities” and “joining forces to confront value crisis”. 展开更多
关键词 SWOT analysis UNIVERSITIES Online Ideological and Political class Driving Strategy
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BLS-identification:A device fingerprint classification mechanism based on broad learning for Internet of Things
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作者 Yu Zhang Bei Gong Qian Wang 《Digital Communications and Networks》 SCIE CSCD 2024年第3期728-739,共12页
The popularity of the Internet of Things(IoT)has enabled a large number of vulnerable devices to connect to the Internet,bringing huge security risks.As a network-level security authentication method,device fingerprin... The popularity of the Internet of Things(IoT)has enabled a large number of vulnerable devices to connect to the Internet,bringing huge security risks.As a network-level security authentication method,device fingerprint based on machine learning has attracted considerable attention because it can detect vulnerable devices in complex and heterogeneous access phases.However,flexible and diversified IoT devices with limited resources increase dif-ficulty of the device fingerprint authentication method executed in IoT,because it needs to retrain the model network to deal with incremental features or types.To address this problem,a device fingerprinting mechanism based on a Broad Learning System(BLS)is proposed in this paper.The mechanism firstly characterizes IoT devices by traffic analysis based on the identifiable differences of the traffic data of IoT devices,and extracts feature parameters of the traffic packets.A hierarchical hybrid sampling method is designed at the preprocessing phase to improve the imbalanced data distribution and reconstruct the fingerprint dataset.The complexity of the dataset is reduced using Principal Component Analysis(PCA)and the device type is identified by training weights using BLS.The experimental results show that the proposed method can achieve state-of-the-art accuracy and spend less training time than other existing methods. 展开更多
关键词 Device fingerprint Traffic analysis class imbalance Broad learning system Access authentication
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A Comparison of Statistics for Assessing Model Invariance in Latent Class Analysis
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作者 Holmes Finch 《Open Journal of Statistics》 2015年第3期191-210,共20页
Latent class analysis (LCA) is a widely used statistical technique for identifying subgroups in the population based upon multiple indicator variables. It has a number of advantages over other unsupervised grouping pr... Latent class analysis (LCA) is a widely used statistical technique for identifying subgroups in the population based upon multiple indicator variables. It has a number of advantages over other unsupervised grouping procedures such as cluster analysis, including stronger theoretical underpinnings, more clearly defined measures of model fit, and the ability to conduct confirmatory analyses. In addition, it is possible to ascertain whether an LCA solution is equally applicable to multiple known groups, using invariance assessment techniques. This study compared the effectiveness of multiple statistics for detecting group LCA invariance, including a chi-square difference test, a bootstrap likelihood ratio test, and several information indices. Results of the simulation study found that the bootstrap likelihood ratio test was the optimal invariance assessment statistic. In addition to the simulation, LCA group invariance assessment was demonstrated in an application with the Youth Risk Behavior Survey (YRBS). Implications of the simulation results for practice are discussed. 展开更多
关键词 latent class analysis MODEL INVARIANCE Information Indices
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Analysis of Public Sentiment regarding COVID-19 Vaccines on the Social Media Platform Reddit
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作者 Lucien Dikla Ngueleo Jules Pagna Disso +2 位作者 Armel Ayimdji Tekemetieu Justin Moskolaï Ngossaha Michael Nana Kameni 《Journal of Computer and Communications》 2024年第2期80-108,共29页
This study undertakes a thorough analysis of the sentiment within the r/Corona-virus subreddit community regarding COVID-19 vaccines on Reddit. We meticulously collected and processed 34,768 comments, spanning from No... This study undertakes a thorough analysis of the sentiment within the r/Corona-virus subreddit community regarding COVID-19 vaccines on Reddit. We meticulously collected and processed 34,768 comments, spanning from November 20, 2020, to January 17, 2021, using sentiment calculation methods such as TextBlob and Twitter-RoBERTa-Base-sentiment to categorize comments into positive, negative, or neutral sentiments. The methodology involved the use of Count Vectorizer as a vectorization technique and the implementation of advanced ensemble algorithms like XGBoost and Random Forest, achieving an accuracy of approximately 80%. Furthermore, through the Dirichlet latent allocation, we identified 23 distinct reasons for vaccine distrust among negative comments. These findings are crucial for understanding the community’s attitudes towards vaccination and can guide targeted public health messaging. Our study not only provides insights into public opinion during a critical health crisis, but also demonstrates the effectiveness of combining natural language processing tools and ensemble algorithms in sentiment analysis. 展开更多
关键词 COVID-19 Vaccine TextBlob Twitter-RoBERTa-Base-Sentiment Sentiment analysis latent Dirichlet Allocation
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Latent semantic analysis for query interfaces of deep web sites 被引量:2
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作者 茅琴娇 冯博琴 潘善亮 《Journal of Southeast University(English Edition)》 EI CAS 2008年第3期312-314,共3页
To further enhance the efficiencies of search engines,achieving capabilities of searching,indexing and locating the information in the deep web,latent semantic analysis is a simple and effective way.Through the latent... To further enhance the efficiencies of search engines,achieving capabilities of searching,indexing and locating the information in the deep web,latent semantic analysis is a simple and effective way.Through the latent semantic analysis of the attributes in the query interfaces and the unique entrances of the deep web sites,the hidden semantic structure information can be retrieved and dimension reduction can be achieved to a certain extent.Using this semantic structure information,the contents in the site can be inferred and the similarity measures among sites in deep web can be revised.Experimental results show that latent semantic analysis revises and improves the semantic understanding of the query form in the deep web,which overcomes the shortcomings of the keyword-based methods.This approach can be used to effectively search the most similar site for any given site and to obtain a site list which conforms to the restrictions one specifies. 展开更多
关键词 deep web information retrieval latent semantic analysis singular value decomposition
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Needs Analysis of English Culture Background Introduction in Spoken English Classes
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作者 王丛丛 《海外英语》 2013年第2X期54-56,共3页
With globalization there is an increasing need for spoken English for Chinese college students. However, the situation of the teaching system of spoken English in most universities in China is not satisfactory. Influe... With globalization there is an increasing need for spoken English for Chinese college students. However, the situation of the teaching system of spoken English in most universities in China is not satisfactory. Influenced by the exam-oriented teaching system, great importance has been put on English grammar and the skills of reading and writing. As a result, students'enthusiasm in improving their spoken English is diminished. Actually, students need some knowledge about English culture background before they can communicate effectively. It is significant for teachers to find out the students'wants and lacks during their spoken English study. Besides, attentions should be paid to English culture background in spoken English classes by both teachers and students. This paper mainly aimed at finding out the needs of students for English culture background in spoken English classes based on the theory of needs analysis. 展开更多
关键词 needs analysis ENGLISH CULTURE BACKGROUND SPOKEN E
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DEPENDENCE ANALYSIS FOR UML CLASS DIAGRAMS 被引量:2
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作者 WuFangjun YiTong 《Journal of Electronics(China)》 2004年第3期249-254,共6页
Though Unified Modeling Language (UML) has been widely used in software development, the major problems confronted lie in comprehension and testing. Dependence analysis is an important approach to analyze, understand,... Though Unified Modeling Language (UML) has been widely used in software development, the major problems confronted lie in comprehension and testing. Dependence analysis is an important approach to analyze, understand, test and maintain programs. A new kind of dependence analysis method for UML class diagrams is developed. A set of dependence relations is definedcorresponding to the relations among classes. Thus, the dependence graph of UML class diagram can be constructed from these dependence relations. Based on this model, both slicing and measurement coupling are further given as its two applications. 展开更多
关键词 Unified Modeling Language (UML) class diagram Dependence analysis Program slicing Measurement coupling
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Semi-supervised learning based probabilistic latent semantic analysis for automatic image annotation 被引量:1
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作者 Tian Dongping 《High Technology Letters》 EI CAS 2017年第4期367-374,共8页
In recent years,multimedia annotation problem has been attracting significant research attention in multimedia and computer vision areas,especially for automatic image annotation,whose purpose is to provide an efficie... In recent years,multimedia annotation problem has been attracting significant research attention in multimedia and computer vision areas,especially for automatic image annotation,whose purpose is to provide an efficient and effective searching environment for users to query their images more easily. In this paper,a semi-supervised learning based probabilistic latent semantic analysis( PLSA) model for automatic image annotation is presenred. Since it's often hard to obtain or create labeled images in large quantities while unlabeled ones are easier to collect,a transductive support vector machine( TSVM) is exploited to enhance the quality of the training image data. Then,different image features with different magnitudes will result in different performance for automatic image annotation. To this end,a Gaussian normalization method is utilized to normalize different features extracted from effective image regions segmented by the normalized cuts algorithm so as to reserve the intrinsic content of images as complete as possible. Finally,a PLSA model with asymmetric modalities is constructed based on the expectation maximization( EM) algorithm to predict a candidate set of annotations with confidence scores. Extensive experiments on the general-purpose Corel5k dataset demonstrate that the proposed model can significantly improve performance of traditional PLSA for the task of automatic image annotation. 展开更多
关键词 automatic image annotation semi-supervised learning probabilistic latent semantic analysis(PLSA) transductive support vector machine(TSVM) image segmentation image retrieval
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Development and Analysis of a Machine Learning Based Software for Assisting Online Classes during COVID-19 被引量:1
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作者 Tasfiqul Ghani Nusrat Jahan +2 位作者 Mohammad Monirujjaman Khan S. M. Tahsinur Rahman Sabik Tawsif Anjum Islam 《Journal of Software Engineering and Applications》 2021年第3期83-94,共12页
<p align="justify"> <span style="font-family:Verdana;">Amid the Covid-19 widespread, it has been challenging for educational institutions to conduct online classes, facing multiples cha... <p align="justify"> <span style="font-family:Verdana;">Amid the Covid-19 widespread, it has been challenging for educational institutions to conduct online classes, facing multiples challenges. This paper provides an insight into different approaches in facing those challenges which includes conducting a fair online class for students. It is tough for an instructor to keep track of their students at the same time because it is difficult to screen if any of the understudies within the class are not present, mindful, or drowsing. This paper discusses a possible solution, something new that can offer support to instructors seeing things from a more significant point of view. The solution is a facial analysis computer program that can let instructors know which students are attentive and who is not. There’s a green and red square box for face detection, for which Instructors can watch by seeing a green box on those mindful students conjointly, a red box on those who are not mindful at all. This paper finds that the program can automatically give attendance by analyzing data from face detection. It has other features for which the teacher can also know if any student leaves the class early. In this paper, model design, performance analysis, and online class assistant aspects of the program have been discussed.</span> </p> 展开更多
关键词 Online class PYTHON Technology Artificial Intelligence analysis Machine Learning Covid-19 SOFTWARE Face Detection Drowsiness Detector
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Prevalence of angle class III malocclusion: A systematic review and meta-analysis 被引量:15
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作者 Daniel K. Hardy Yltze P. Cubas Maria F. Orellana 《Open Journal of Epidemiology》 2012年第4期75-82,共8页
Objective: This study seeks to review current and relevant literature on global Angle class III malocclusion prevalence. Materials and Methods: The electronic databases PubMed, ISI Web of Knowledge, and the Cochrane D... Objective: This study seeks to review current and relevant literature on global Angle class III malocclusion prevalence. Materials and Methods: The electronic databases PubMed, ISI Web of Knowledge, and the Cochrane Database of Systematic Review were searched using specific inclusion criteria to obtain applicable articles. All pertinent references were also examined for acceptability. Results: A total of 20 articles were identified using the inclusion criteria. The prevalence of Angle class III malocclusion ranged from 0 to 26.7% in different populations reported in the literature examined. Meta-regression analysis showed no statistically significant association between prevalence rates and the method of assessment, age group and year of the study. However, much of the study-to-study variation (approximately 40%) could be explained by population. Conclusion: These results suggest that the prevalence of Angle class III malocclusion varies greatly within different races and geographic regions. Chinese and Malaysian populations have a higher prevalence of Angle class III malocclusion compared to other racial groups, while Indian populations have a lower prevalence than all other racial groups examined. 展开更多
关键词 MALOCCLUSION class III PREVALENCE Systematic REVIEW META-analysis
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New approaches to cognitive work analysis through latent variable modeling in mining operations
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作者 S.Li Y.A.Sari M.Kumral 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2019年第4期549-556,共8页
This paper discusses the utilization of latent variable modeling related to occupational health and safety in the mining industry.Latent variable modeling,which is a statistical model that relates observable and laten... This paper discusses the utilization of latent variable modeling related to occupational health and safety in the mining industry.Latent variable modeling,which is a statistical model that relates observable and latent variables,could be used to facilitate researchers’understandings of the underlying constructs or hypothetical factors and their magnitude of effect that constitute a complex system.This enhanced understanding,in turn,can help emphasize the important factors to improve mine safety.The most commonly used techniques include the exploratory factor analysis(EFA),the confirmatory factor analysis(CFA)and the structural equation model with latent variables(SEM).A critical comparison of the three techniques regarding mine safety is provided.Possible applications of latent variable modeling in mining engineering are explored.In this scope,relevant research papers were reviewed.They suggest that the application of such methods could prove useful in mine accident and safety research.Application of latent variables analysis in cognitive work analysis was proposed to improve the understanding of human-work relationships in mining operations. 展开更多
关键词 latent variables EXPLORATORY FACTOR analysis Confirmatory FACTOR analysis Structural equation modeling OCCUPATIONAL health and SAFETY Mine SAFETY
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Understanding the Effects of Various Factors on the Public Response to Congestion Charge: A Latent Class Modeling Approach
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作者 Sugiarto Sugiarto Tomio Miwa +1 位作者 Hitomi Sato Takayuki Morikawa 《Journal of Transportation Technologies》 2015年第2期76-87,共12页
The standard ordered response model (SORM) is a common disaggregate approach with ordered outcomes in which the effects of various exogenous attributes are assumed constant across ordinal choices. In this study, an in... The standard ordered response model (SORM) is a common disaggregate approach with ordered outcomes in which the effects of various exogenous attributes are assumed constant across ordinal choices. In this study, an innovative latent class based generalized ordered response model (LC-GORM) is formulated and used to assess the effects of various factors on respondents’ choice behavior with respect to congestion charge proposal for Jakarta, Indonesia. The proposed model probabilistically assigns respondents into selfish and altruistic class memberships (latently) based on their knowledge of the proposed scheme and their specific attributes. Aiming to capture observable preference heterogeneity across ordinal choices and allow the thresholds to be varied across observations, we parameterize the thresholds as a linear function of the exogenous variables for each ordinal preference. Using stated preference data collected in Jakarta in December 2013, we incorporate the influence of a comprehensive set of explanatory variables into four categories: charges, latent variables related to respondent’s psychological motivations, mobility attributes and socio-demographic characteristics. Empirical results obviously verify the existence of preference heterogeneity across outcomes. The findings confirm that the altruistic class are more sensitive with respect to acceptance of the scheme, while the selfish class are more sensitive with respect to rejection. The key factors influencing public acceptability include the charge level and respondent variables such as car dependency, awareness of the problem of cars in society, frequency of visits to the city center and frequency of private mode usage. 展开更多
关键词 Respondent’s CHOICE Behavior latent Types of RESPONDENTS latent class CONGESTION CHARGE
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A CLASS OF EBE TIME INTEGRATION ALGORITHMS FOR TRANSIENT FINITE ELEMENT STRUCTURAL DYNAMICAL ANALYSIS
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作者 Deng Shaozhong Zhou Shuquan(College of Science, Naming University of Aero. Astro.Naming 210016, P.R. China) 《Wuhan University Journal of Natural Sciences》 CAS 1996年第Z1期495-501,共7页
A new class of algorithms for trails lent finite element structural dynamical analysis which is amenable to all efficient implementation inl parallel computers (especially Massively Parallel Computers) is proposed. Th... A new class of algorithms for trails lent finite element structural dynamical analysis which is amenable to all efficient implementation inl parallel computers (especially Massively Parallel Computers) is proposed. The suitability of the method for parallel computation stems from the fact that, gived an arbitrary partition of the finite element mesh, each element in the partition can be processed over a time step independently and simultaneously with the rest, and no global equation solving effort is involved. Although the Proposed EBE time integration algorithms are shown to have the structure of an explicit scheme, they are unconditionally stable over a certain range of the algorithmic parameter. 展开更多
关键词 EBE TIME OF class INTEGRATION ALGORITHMS analysis
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Latent Class Approach to Estimate the Willingness to Pay for Transit User Information
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作者 Pietro Zito Giuseppe Salvo 《Journal of Transportation Technologies》 2012年第3期193-203,共11页
The aim of analysis is to understand how unreliable information influences user behaviour and how much it discourages public transport use. For this purpose, a Stated Preference Survey was carried out in order to know... The aim of analysis is to understand how unreliable information influences user behaviour and how much it discourages public transport use. For this purpose, a Stated Preference Survey was carried out in order to know the preferences of public transport users relating to information needs and uncertainty on the information provided by Advanced Traveller Information System (ATIS). The perceived uncertainty is defined as information inaccuracy. In our study, we considered the difference between forecasted or scheduled waiting time at the bus stop and/or metro station provided by ATIS, and that experienced by user, to catch the bus and/or metro. A questionnaire was submitted to an appropriate sample of Palermo’s population. A Latent Class Logit model was calibrated, taking into account attributes of cost, information inaccuracy, travel time, waiting time, and cut-offs in order to reveal preference heterogeneity in the perceived information. The calibrated model showed various sources of preference heterogeneity in the perceived information of public transport users as highlighted by the analysis reported. Finally, the willingness to pay was estimated, confirming a great sensitivity to the perceived information, provided by ATIS. 展开更多
关键词 PREFERENCE Heterogeneity latent class Model PERCEIVED Information Uncertainty WILLINGNESS to PAY
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