• Progress in Superconductivity
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• v.12 no.1
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• pp.27-31
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• 2010

A superconductor flywheel energy storage system (SFES) is an electro-mechanical battery which transforms electrical energy into mechanical energy for storage, and vice versa. Many aspects of the quasi-static behavior of flywheel rotors still need to be studied closely, and the rotors require a stable and highly efficient supporting system such as high temperature superconductor (HTS) bearings, which offer dynamic stability without the use of active control. Quasi-static properties of HTS bearings in the radial direction provide data to solve problems which may occur in a running system. Since stiffness in countering rotor vibration is the main parameter for designing an HTS bearing system, we investigated the quasi-static properties of the magnetic force between permanent magnets(PMs) and HTS bulks in the radial direction. We measured radial stiffness, and discovered that bearing stiffness varied greatly depending on the number of active HTS bulks. This is valuable data for predicting the change in stiffness during partial HTS bearing failure. The quasi-static test results are used for optimal design and performance prediction for the 100 kWh class superconductor bearing.

• Journal of Chest Surgery
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• v.26 no.2
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• pp.141-147
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• 1993

A total of 40 patients having a diagnosis of atherosclerotic coronary arterial disease were analysed on the operative outcomes according to variables as follows: 1) preoperative risk factors such as age, sex, CCS (Canadian Cardiovascular Society) functional class, type of angina, number of diseased vessel, presence of left main coronary artery stenosis, previous history of habitual smoking and presence of other medical diseases (diabetes mellitus, essential hypertension), 2) preoperative management such as intravenous infusion of nitroglycerine, preoperative IABP (intra-aortic balloon pump) support and whether the operation was scheduled as emergency or not, 3) intraoperative variables such as infusion method and composition of cardioplegic solutions, number of distal anastomosis, use of internal mammary artery, total cardiopulmonary bypass time and total cross clamp time. Complications included operative death in 12.5％, perioperative myocardial infarction in 25.0％ and perioperative arrhythmia in 17.5％. Nineteen perioperative variables were analyzed to identify risk factors for these end points. For operative death, presence of left main coronary artery stenosis (p = 0.056) and cardiopulmonary bypass time (p = 0.029) were significant in the univariate analysis, but presence of left main coronary artery lesion (p = 0.011, $\chi$$^2$= 6.45) and abscence of preoperative of IABP support (p = 0.069, $\chi$$^2$ = 3.30) were independent predictor in multivariate analysis (stepwise linear logistic regression).

• Journal of Korean Academy of Nursing
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• v.3 no.1
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• pp.53-66
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• 1972

There is an urgent need to improve the tool predicting success or failure of academic achievement of nursing in Korea so as to identify as early as possible those students who should receive special instruction and to improve screening procedures for admission of nursing. The main purpose of this study is to identify the correlation between the grade point averages of courses learned and their psychological test characteristics in a baccalaureate nursing program. All 240 students, except freshmen, enrolled in Nursing Department of Seoul National University in the spring semester, 1972, participated in this study. All of the subjects completed the psychometric tests such as interest test, personality test and test of self-concept. Total grade point averages, grade point averages of general education subjects, of supporting science courses and of professional education subjects were used as performance criteria of the students. Through the calculation of product-moment correlation coefficients between the test scores and four grade point averages of each class and of total subjects, the following findings and recommendations were obtained. 1. There was so much variation in characteristics of interest test correlated with academic achievement of nursing students in each class. 2. Since the school objectives, curriculum and teaching strategies may affect predictive efficiency of characteristics of students'interest test, interest test must-be utilized in a homogeneous group in order to predict school achievement. 3. Characteristics of interest test positively correlated at significant level with total grade point averages of all subjects were scientific interest-biological, scientific interest-physical, and humanitarian interest. Scientific interest-physics: was the only characteristic positively correlated at significant level with total grade point averages and grade point averages of professional courses. 4. There were various patterns in characteristics of personality test correlated with school achievement of nursing students by class pattern and personality maturation as they progress toward higher classes. 5. A characteristic of personality test, responsibility, is in high positive correlation with academic achievement in the upper division of classes. 6. Responsibility was the sole personality factor positively correlated at significant level with total grade point averages and grade point averages of nursing courses in the total number of students. 7. There were very different correlation coefficients between characteristics of self-concept test and academic achievement according to the type of each class and type of courses they learned. 8. Characteristics of self-concept test positively correlated at significant level with total grade point averages and grade point averages of nursing courses of all students were physical self and row variability. Those who have positive concept on their own physical status and who are deficient in self-concept were higher in total grade point averages and grade point averages of professional courses than other students. 9. Scores of professional courses offered in freshmen and sophomore classes were in positive correlation with limited number of characteristics of psychological tests. In pursuit of a tool predicting successful academic achievement of nursing students, their G.P.A. during the junior and senior year of nursing will serve as the more reasonable criteria. 10. Junior students of this school were in higher positive correlation with many psychological factors than other classes.

• Journal of Environmental Health Sciences
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• v.41 no.3
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• pp.203-215
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• 2015

Objectives: This study was designed to evaluate the filtration efficiencies and pressure drops of five commercial cloth masks (4 plate type, 1 cup type) in comparison to the performance of a class 1 disposable respirator (reference respirator). A further objective was to evaluate the effects of the number of layers and wash treatment independently on filtration efficiencies and pressure drops. Methods: Polydisperse NaCl aerosols were generated in an aerosol chamber and their concentrations were measured by an optical particle counter (OPC) in the size range of $0.3{\sim}10{\mu}m$ (five channels). Results: The filtration efficiencies of the five cloth masks and the reference respirator were D: 9.5%, C: 18.5%, E: 23.6%, A: 28.5%, B: 29.7% and R: 91.1%, respectively, and the pressure drops through them were C, D: 0.8 Pa, E: 1.7 Pa, B: 6.4 Pa, A: 42.7 Pa and R: 19.3 Pa, respectively. The filtration efficiencies of the cloth masks and reference respirator were below the class 1 respirator criterion (${\geq}94.0%$) of the Ministry of Employment and Labor (MOEL) and Ministry of Food and Drug Safety (MFDS). The pressure drops satisfied the class 1 respirator criterion (${\leq}70Pa$) of MOEL and MFDS. When the cloth masks were folded into two and four layers, the filtration efficiencies of cloth masks A, B, C, D (plate type) increased 1.7-4.6 times, and 2.3-6.8 times, respectively, compared to the efficiencies of the same products in a single layer. Pressure drops increased as the number of layers was increased. The filtration efficiency of cloth mask E with a liner was 1.3 times higher than that of the same mask without a liner, and the pressure drop was lower in the no-liner configuration. After a single washing, the filtration efficiencies of all the cloth mask products decreased 1.04-4.0 times compared to those of the same products intact. For the cloth masks C and E, their filtration efficiencies were significantly decreased after washing (p<0.05). The pressure drops of all cloth masks were 1.2-2.0 times lower after washing. Conclusions: The filtration efficiencies of the five cloth masks were below 30% and did not improve greatly by increasing the number of layers. After a single washing, their performances decreased. Considering the above and other issues identified with cloth masks, such as poor fit and stretched fibers through use, people should not expect protection against particulate matters from the cloth masks on the market.

• Korean Journal of Community Nutrition
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• v.4 no.4
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• pp.504-511
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• 1999

The purpose of this survey was to investigate the relationship among obese children, dietary intake and environmental factors. Therefore, this survey compared obese children with normal children on dietary intake and environmental factors. The survey were 110 obese children and 110 normal children whose age, height, and sex were same as the obese children of 21 elementary school in Inchon. The statistical analysis of data was completed using SAS program. The results were summarized as follows : 1) The student's obesity was related to parent's obesity and number of their siblings. There were significant differences between obese groups and normal group for these two factors. 2) Meal time of the obese group showed more irregularity than that of the normal group. Otherwise, the normal group were more "piclity" about special food than the obese group(p<0.05). Also obese children showed unconsious eating while reading or watching TV(p<0.01). The normal group attended physical education class more eagerily the obese group(p<0.001). There was no significant difference between obese children and normal children for learning habits. 3) Obese children shoed higher intake of nutrients compared to normal children. Among all the nutrients, minerals and vitamins showed significant differences. Therefore, further study on obese children and their intake of minerals and vitamin is needed. Also, in order to prevent factors which influence obesity, nutrition education at home as well as school was needed.as needed.

• Journal of the Korean Society of Food Culture
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• v.6 no.2
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• pp.155-173
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• 1991

This study was conducted to research on the observing state of Korean traditional holidays and the traditional foods related to those days through the questionnaires completed by 578 housewives who live in Kangreung, Daejeon, Jeonju, and Daegu area. For data processing, SAS program was employed, and all data was analyzed by frequency, percentage, and $x^2-square$. The results are as follows; 1. In observing the traditional holidays, more than 90% of housewives who answered the inquiry keep up SEOLNAL, DAEBOREUM, and CHUSEOK, whithout regarding regions. There are larger number of people who keep up IPCHUN, JUNGWHAJEAL, and DANOH in Kangreung and SAMBOK in Daegu than that of other regions (p<.001). Compared to general circumstances, CHOPAIL is more commonly celebrated by older class as well as lower educated class (p<.001) Also, the consequence shows that Buddhists observe IPCHUN, SAMJITANL, CHOPAIL, DANOH, SAMBOK, and DONGJI more commonly compared with other classes (p<.001), IPCHUN, SAMJITNAL, (p<.01). DAEBOREUM, YUDU, SAMBOK, JUNGYANGJEOL, OHIL, and DONGJI (p<.001) are celebrated more generally among extended. 2. On inheritance of the traditional holidays, most of the housewives answered that the SEOLNAL, DAEBOREUM, CHUSSEOK, and DONGJI are to be inherited. Compared to general circumstance CHOPAIL is suggested to be inherited by older people (p<.001). The IPCHUN, CHOPAIL, SAMBOK (p<.001), and DANCH (p<.01) are suggested by Buddhists that YUDU and SAMBOK are by nuclear. 3. In preparaing festive foods, DEOKGUK on SEOLNAL, OHKOKBAP and MUKEUNNAMUL on DAEBOREUM, SONGPYEON and GATEUNNAMUL on CHUSEOK, and PATJUK on DONGJI are being made very generally. KANGJEONG on SEOLNAL, BUREUM on DAEBOREUM, KALGUKSU and SAMGYAETANG on SAMBOK, DARKJIM on CHUSEOK, SUJEONGGWA and DONGCHIMI on DONGJI appeared comparatively high rated of making. 4. In normal times, DEOKGUK, MANDU, INJEOLMI, SIKHYAE, SUJEEONGGWA, PYEONYUK, JEONYUEO, SIRUDDEOK, BOKSSAM, MUKEUNNAMUL, SONGPYUN, MINARINAMUL, YUKGAEJANGGUK, KALGUKSU, SAMGYAETANG, HOBAKJIJIM, TORANTANG, GATEUNNAMUL, NUREUMJEOK, DAKJIM, KALBIJIM, PATJJUK, and DONGCHIMI is usully made. 5. The source to learn about traditional foods is mostly by her mother and the rest orders are husband's mother, cooking books, mass media (including T.V), school education, and cooking instituse, etc.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.11
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• pp.584-593
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• 2017

This study provides basic data needed to improve the working environment of the first class emergency medical technicians, in order to decrease their job stress and increase their job satisfaction. Job stress and satisfaction were compared and analysed in emergency medical technicians who were working for 119 rescue and hospitals at the time when twenty-one years had passed after the initial training of emergency medical technicians in order to identify differences between 119 rescue and hospitals, and their advantages and disadvantages. The subjects of the study were 182 first-class emergency medical technicians who were working in twenty-eight 119 rescue centers and fourteen national and local emergency medical centers in Gwangju, Jeollanamdo and Jeollabukdo. The study subjects were interviewed by questionnaire. For statistical analysis, SPSS/WIN 20.0 was used, and the results were analysed with chi-square, t-test, ANOVA, and ANCOVA testing. There was no significant difference in job stress between the subjects working in 119 rescue centers (2.92) and those working in hospitals(3.01). The satisfaction score of fire-fighting workers was 2.98 and that of hospital workers was 2.54. Hospital workers' satisfaction was significantly lower (p<0.001). The score of hospital workers' pay satisfaction was the lowest($2.07{\pm}0.62$). The job stress decreased and job satisfaction increased with decreasing monthly average number of patients(p<0.001), increasing monthly income(p=0.047), and more frequent holidays they had(p<0.001), the less. For less job stress and higher job satisfaction, welfare conditions both at 119 rescue and hospitals should be improved. 119 rescue centers should develop violence prevention measures and offer resting places for emergency medical technicians. Hospitals should pay more attention to the yearly pay increase rate and stability in employment types.

• Journal of the Korean Society of School Health
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• v.22 no.1
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• pp.49-59
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• 2009

Purpose: The aim of this study was to identify the factors related with the intention of smoking abstinence among elementary students in a metropolitan city in Korea. Methods: All the elementary schools in the city were stratified by region, and then schools as a primary sampling units (PSU) were selected by probability proportional to size (PPS) sampling. One class per grade was sampled randomly from 5th and 6th grade in the sampled schools from October to December in 2004. The students completed a standardized self-administered questionnaire anonymously. A total number of 1,712 respondents who did not smoke was included in the final analysis. The dependent variable was an intention of smoking in the future, and it was dichotomized into 'absolutely confident in smoking abstinence' and 'others'. The risk of non-absolute confidence in smoking abstinence was calculated with simple and multiple logistic regression, which were conducted with STATA 9.0 by a design-based analysis considering strata variable, PSU, and sampling weight. Results: In the final model of multiple logistic regression analysis, those who were more likely to have non-absolute confidence in smoking abstinence were male students (OR=2.66, p<0.001); barely attending religious services (OR=3.32, p=0.002) or having no religion (OR=1.95, p=0.027); exposure to environmental tobacco smoke outside home 1${\sim}$2 days per week (OR=1.60, p=0.013); having friends who smoked (OR=1.93, p=0.011); non-absolute confidence in refusing to smoke (OR=5.35, p<0.001); having relatively less negative attitude (OR=2.88, p<0.001), positive attitude (OR=2.35, p<0.001), and indifference (OR=4.05, p=0.034) toward peer smoking; not good relationship with mother (OR=1.52, p=0.016). Conclusion: The factors related with non-absolute confidence in smoking abstinence were coincided with those of smoking among children. The results of this study suggest the smoking prevention education should be applied to the children more actively, especially who are not confident in smoking abstinence in the future.

• Journal of Broadcast Engineering
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• v.21 no.6
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• pp.929-943
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• 2016

This paper proposes the rate control algorithm based on the S-JND (Saliency-Just Noticeable Difference) model for considering perceptual visual quality. The proposed rate control algorithm employs the S-JND model to simultaneously reflect human visual sensitivity and human visual attention for considering characteristics of human visual system. During allocating bits for CTU (Coding Tree Unit) level in a rate control, the bit allocation model calculates the S-JND threshold of each CTU in a picture. The threshold of each CTU is used for adaptively allocating a proper number of bits; thus, the proposed bit allocation model can improve perceptual visual quality. For performance evaluation of the proposed algorithm, the proposed algorithm was implemented on HM 16.9 and tested for sequences in Class B and Class C under the CTC (Common Test Condition) RA (Random Access), Low-delay B and Low-delay P case. Experimental results show that the proposed method reduces the bit-rate of 2.3%, and improves BD-PSNR of 0.07dB and bit-rate accuracy of 0.06% on average. We achieved MOS improvement of 0.03 with the proposed method, compared with the conventional method based on DSCQS (Double Stimulus Continuous Quality Scale).

• Korea Journal of Hospital Management
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• v.21 no.3
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• pp.11-21
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• 2016

The purpose of this study is to investigate the degree of difficulty and turnover of nurses working in the field and to derive clinical work activation and supply policy improvements. Data was collected from December, 2014 to January, 2015, from 23 hospitals, and participants were 3,887 nurses working in the field, Survey details : the difficulty of the clinical work of nurses working in hospitals, turnover intentions status and policy proposals for clinical research work enabled General characteristics, difficulties in clinical working, turnover intention and clinical work plan activation are frequency analysis. The difference between each of the variables in accordance with the general characteristics are one-way ANOVA analysis, Correlation analysis of the variables is also a Pearson correlation coefficients. 'difficulties in clinical working' was a statistically significant difference depending on the type of hospital, nursing class, number of beds, location, age, position, employment, gender, working form, working department, salary, career, and degree level. 'turnover intention' was a statistically significant difference depending on nursing rate, number of beds, region, age, position, sex, shifts, departments, annual income, and career. 'policy recommendation' was a statistically significant difference depending on type of hospital, nursing rate, age, position, employ, shifts, departments, annual income, degree level and career 'difficulties in clinical working' is 'turnover intention' (p<.001), 'policy recommendations' (p<.001) and had a significant positive correlation. and 'turnover intention' had a "policy recommendation" significant positive correlation with the relationship (p<.001) The most difficulties point of the nurses working in the field are the environment, such as shift, urgent and dangerous. Major policy proposals are improve treatment such as wages, and welfare.