• Wind and Structures
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• v.32 no.2
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• pp.143-159
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• 2021

The 246.8-m-tall Beijing Olympic Tower (BOT) is a new landmark in Beijing City, China. Its unique architectural style with five sub-towers and a large tower crown gives rise to complex dynamic characteristics. Thus, it is wind-sensitive, and a double-stage pendulum tuned mass damper (DPTMD) has been installed for vibration mitigation. In this study, a finite-element analysis of the wind-induced responses of the tower based on full-scale measurement results was performed. First, the structure of the BOT and the full-scale measurement are introduced. According to the measured dynamic characteristics of the BOT, such as the natural frequencies, modal shapes, and damping ratios, an accurate finite-element model (FEM) was established and updated. On the basis of wind measurements, as well as wind-tunnel test results, the wind load on the model was calculated. Then, the wind-induced responses of the BOT with the DPTMD were obtained and compared with the measured responses to assess the numerical wind-induced response analysis method. Finally, the wind-induced serviceability of the BOT was evaluated according to the field measurement results for the wind-induced response and was found to be satisfactory for human comfort.

• Journal of Acupuncture Research
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• v.40 no.2
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• pp.143-149
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• 2023

Functional dyspepsia (FD) is a chronic and recurrent upper gastrointestinal symptom that has no organic cause. A 49-year-old male patient positive for human immunodeficiency virus (HIV) visited the clinic because of FD and constipation. He received complex Korean medicine treatment, including acupuncture and herbal medicines, from April 14 to July 18, 2022 (27 times) in the outpatient department. Gastrointestinal Symptom Rating Scale (GSRS), Nepean Dyspepsia Index (NDI), FD-related quality of life (FD-QoL), Euro QoL visual analog scale (EQ-VAS), and Numerical Rating Scale (NRS) were used as evaluation tools in this study. Symptoms were relieved after 3 months of treatment, and his QoL improved (GSRS, 15-3; NDI, 110-21; FD-QoL, 52-20 [eating status, 10-3; liveliness status, 12-8; psychological, 1-0; role-functioning status, 18-9]; EQ-VAS, 40-65; NRS, 8-4). The results revealed that complex Korean medicine treatment could alleviate FD and constipation in patients with HIV.

• International Journal of Computer Science & Network Security
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• v.24 no.7
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• pp.207-213
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• 2024

This study investigated the perceived usability of the Blackboard learning management system (LMS) amongst students at Umm Al-Qura University. A quantitative approach was employed to explore the potential relationship between Blackboard usability and social media platform usage. Additionally, the study aimed to identify other factors influencing perceived usability. Data were collected through a three-section questionnaire distributed electronically to a sample of students (n=544). The findings, based on System Usability Scale (SUS) scores, revealed that the overall perceived usability of Blackboard resided near the midpoint of the scale, indicating an "acceptable" level. A potential negative correlation emerged between social media usage time and perceived Blackboard usability. Students who reported lower social media usage exhibited higher SUS scores. Training on Blackboard usage demonstrably exerted a positive influence on perceived usability. Gender was not identified as a statistically significant factor. An analysis of student support methods revealed that seeking help from a friend was the most prevalent approach, followed by search engines, university technical support, and social media platforms. The findings suggest that implementing strategies to improve Blackboard usability at Umm Al-Qura University could be achieved through readily accessible training materials and the exploration of alternative support channels.

• Human Ecology Research
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• v.52 no.1
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• pp.43-53
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• 2014

The purpose of this study was to 1) investigate the characteristics of burnout of Korean elementary school students and 2) develop and validate the Korean Academic Burnout Scale-Elementary School Students (KABS-ESS). Fifty-one behavioral descriptions of burnout extracted through a preliminary survey, focus group interview, and literature review were administered to a sample of 531 elementary students of the 4th to 6th grade in Gyeonggi Province. The results of an exploratory factor analysis indicated that the structure of the burnout of Korean elementary school students consists of seven factors (i.e., inefficacy, avoidance, cynicism, emotional exhaustion, physical exhaustion, antipathy and cognitive exhaustion), and this structure of final 28 items was confirmed by the confirmatory factor analysis. The KABS-ESS showed a correlation of .771 with a representative academic burnout scale, Maslach Burnout Inventory-Student Survey, and -.561 with the academic engagement scale, indicating that both convergent and discriminant validities were confirmed. Furthermore, all fit indices of the structural equation model of the Schaufeli and Bakker's job demands-resources in an academic setting were satisfactory, and the possibility of the validity generalization of the model was supported. The demand variables predicting academic burnout and engagement were academic overload and parental pressure, while self-resilience, self-regulated learning strategies, and parental and the teacher's support were identified as the resource variables. Lastly, the implications and future direction of the present study were discussed.

• Journal of Institute of Control, Robotics and Systems
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• v.10 no.12
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• pp.1164-1171
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• 2004

A new multi-scale simulation model is proposed to analyze heart mechanics. Electrophysiology of a cardiac cell is numerically approximated using the previous model of human ventricular myocyte. The ion transports across cell membrane initiated by action potential induce an excitation-contraction mechanism in the cell via cross bridge dynamics. Negroni and Lascano model (NL model) is employed to calculate the tension of cross bridge which is closely related to the ion dynamics in cytoplasm. To convert the tension on cell level into contraction force of cardiac muscle, we introduce a simple geometric model of ventricle with a thin-walled hemispheric shape. It is assumed that cardiac tissue is composed of a set of cardiac myocytes and its orientation on the hemispheric surface of ventricle remains constant everywhere in the domain. Application of Laplace law to the ventricle model enables us to determine the ventricular pressure that induces blood circulation in a body. A lumped parameter model with 7 compartments is utilized to describe the systemic circulation interacting with the cardiac cell mechanism via NL model and Laplace law. Numerical simulation shows that the ion transports in cell level eventually generate blood hemodynamics on system level via cross bridge dynamics and Laplace law. Computational results using the present multi-scale model are well compared with the existing ones. Especially it is shown that the typical characteristics of heart mechanics, such as pressure volume relation, stroke volume and ejection fraction, can be generated by the present multi-scale cardiovascular model, covering from cardiac cells to circulation system.

• Journal of Environmental Science International
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• v.25 no.3
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• pp.425-438
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• 2016

This study carried out zeta potential measurements of the Microcystis sp. under various solutions condition and investigated the characteristics of Microcystis sp. through the size control of microbubbles to eliminate algae that causes problems in aquatic ecosystems and human activities. DAF process was adopted and several coagulants were used to remove the Microcystis sp. CCD Camera was used to measure and analyze the size of microbubble, and fluorescent microscope was used to observe the particle, algae species and community. Zeta potential behavior of the algae was analyzed by using ELS-Z. Lab-scale and pilot-scale experiments were conducted to test flotation process. Polyaluminium chloride(PAC) coagulant was used, and the removal efficiency of the algae was assessed through Chlorophyll-a analysis. In the Lab-scale experiment, 2.2 ppm, 11 ppm, 22 ppm, and 44 ppm of polyaluminium chloride was injected to coagulate the algae. The coagulated algae was floated by the microbubble. The microbubbles in the experiments were generated at a air pressure of 450 ~ 550 kPa. The microbubble size was controlled in $36{\mu}m$, $100{\mu}m$, and $200{\mu}m$, respectively by using different diffuser. The results of lab-scale experiments on flotation plant indicated that the average removal rate was about 90% or above for 11 ppm, 22 ppm, and 44 ppm of polyaluminium chloride. On the other hand, in the pilot-scale experiment, the removal efficiency was in the range of 85% to 95% in all dose ranges of polyalumium chloride and aluminium sulfate coagulants.

• International Journal of Human Ecology
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• v.2 no.1
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• pp.39-55
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• 2001

Concerns about paid-facilities for the elderly with dementia from middle and upper class families have been discussed lately in Korea. Small-scale, home-like group homes for the elderly with dementia were developed in Sweden in the 1980, but they have not been effectively introduced in Korea where they remain a comparatively new concept. The group home, however, would provide a good alternative to Koreans who feel guilty when they have to leave their frail parents in large-scale facilities or hospitals instead of caring for them at home. The aim of this paper is, first, to define the care of the demented elderly who come from upper and middle class families in Korea and, secondly, to discuss the need for group homes to help care for them. A survey was done by questionnaire and was answered by 577 respondents who belonged to middle and upper class families living in Korea in December 2000. Methods of analysis were frequency, mean, and Chi-square. The results of this study were as follows: 1) the traditional notion that the eldest son should be burdened with the primary responsibility for a demented parent has weakened remarkably; 2) a small-scale long-term care facility was considered the most desirable living environment for the demented elderly; 3) the facilities families needed for professional hospitals for victims of dementia, senior citizen centers, large and small-scale long-term care facilities, day-care centers, and short-stay and service housing. The study also revealed that there was low awareness of the group home. The most preferred type of structure for group homes was a single-family detached house, and the most preferred management system was small-scale that could create home-like atmosphere. Additionally the respondents wanted group homes to consist of 6-8 residents with 2-4 persons per room. The results of this study strongly suggest that policy makers should encourage the development of smallscale group homes as an alternative form of housing for the elderly with dementia.

• Atmosphere
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• v.26 no.3
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• pp.445-459
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• 2016

Air temperature deviation (ATD) is one of major indicators to represent spatial distribution of urban heat island (UHI), which is induced from the urbanization. The purpose of this study is to evaluate the accuracy of air temperature deviation about Climate Analysis Seoul (CAS) workbench, which had developed by National Institute Meteorological Science and TU Berlin. Comparison and correlation analysis for CAS ATD including meso-scale air temperature deviation, local-scale air temperature deviation, total air temperature deviation, surface heat flux deviation, cold air production deviation among meso-scale numerical modelling variable in 'Seoul Region', micro-scale numerical modelling in 'Detail Region', and CAS workbench variable using observation data in ground stations. Comparison between night time OBS ATD and CAS ATD show that have most close values. Most of observations ($dT_{max}$ and $dT_{min}$) have highly positive ($dT_{SHP}$, $dT_{CA}$, MD, TD, $f_{BS}$, $f_{US}$, $f_{WS}$, $h_B$) and negative ($f_{VS}$, $f_{TV}$, $h_V$, Z) correlations. However, CAS workbench needs further improvement of both observational framework and analytical framework to resolve the problems; (1) night time OBS ATD of has closer values in compare with at high rise mountain area and (2) correlations are very dependable to meteorological scale.

• The Research Journal of the Costume Culture
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• v.24 no.6
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• pp.709-724
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• 2016

The purpose of this study is to develop a multi-dimensional scale measuring consumers' perceived challenge in shopping fashion products online, and to verify its validity and reliability. Relevant literature is first reviewed to identify possible dimensions of perceived challenge. Next, Study 1 is conducted in order to explore the dimensions empirically and to see whether the dimensions that emerged were consistent with prior findings. A total of 190 responses to an open-ended question was qualitatively analyzed by using content analysis. The findings of Study 1 generate 26 items reflecting four dimensions (i.e., product knowledge, previous experience, website functionality, and product availability), which correspond to the dimensions suggested in literature review. Study 2 is subsequently conducted to refine the items so that the perceived challenge scale establishes cross-validation, convergent validity, discriminant validity, reliability, and predictive validity. A total of 238 responses is quantitatively analyzed by using exploratory factor analysis, confirmatory factor analysis, and structural equation modeling. In the results of Study 2, the perceived challenge scale is found to consist of a total of 16 items reflecting three dimensions: E-commerce Challenge (corresponding to Previous Experience reported in Study 1), Retailer Challenge (corresponding to Website Functionality), and Product Challenge (corresponding to Product Knowledge); all Product Availability items have been eliminated through the item refinement process. Specifically, E-commerce Challenge and Retailer Challenge are found to predict flow, supporting flow theory, while Product Challenge fails to lead to flow significantly. Implications, limitations, and suggestions for future studies are also discussed.

• The Journal of the Korea Contents Association
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• v.12 no.2
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• pp.232-242
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• 2012

The purpose of this study was to analyze the multiple regression between the psychological well-being, Empathy ability Scale and Job Efficiency at relationship among on Teacher's job satisfaction among elementary, middle, high the whole country. It aims to find a method that can improve teacher's job satisfaction. The subjects for this study were 308 teacher's composed of 196 out of elementary school teachers, 62 out of middle school teachers and 50 out of high school nation wide. The result and discussion are as follows:First, if we take a look teacher's psychological well-being, Empathy ability Scale and Job Efficiency autonomy and school administration, compensation system, personal growth and school administration, compensation system, working environment, purpose of life and school administration, positive interpersonal relationships, self acceptance among subordinate variables of psychological well-being, empathy ability scale, job efficiency of teachers at are all relevant to of subordinate variables except compensation system. Second, as a result of the multiple regression analysis, the significant variables which affect teacher's job satisfaction are ranked in the order of human relationships, self acceptance, emotional factors. whole all variables are not significant.