• KSCE Journal of Civil and Environmental Engineering Research
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• v.5 no.4
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• pp.75-86
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• 1985

A beam with web opening may reduce the cost of steel and the height of multistory steel buildings. Bower's analysis based on the theory of elasticity and Vierendeel analysis had evaluated the normal stresses around the holes, but these analyses have difficulties for practical uses because of complexity and the limitation for their application. In this study, it is shown that the finite element method, using smaller number of isoparametric elements by taking only a part of the beam which includes the hole, can diminish defects of the above two methods and it may represent more satisfactorily the distribution of the local stress concentration around the hole than the other methods which employed linear elements such as in the analysis by Samuel or Redwood. This study presents the effects of moments, shears, and eccentricities of a hole on the distribution of the normal stresses calculated by using the proposed finite element method. Consequently, it is found that the variations of shear force and hole depth give significant effects on the normal stresses around a hole, while the variations of eccentricities of the hole provide a little effect on them. The regression coefficients resulted from the multiple linear regression may be used for estimating the normal stresses around any arbitrary hole in the web of a beam, since the normal stresses guessed by this regression coefficient equation match well the results by the finite element method except the case of large eccentricity.

• Journal of Digital Convergence
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• v.13 no.8
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• pp.375-385
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• 2015

This study aims to identify geographical variations and factors that affect smoking rates. The data are collected from the Community Health Survey conducted between 2009 and 2011 by Korea Centers for Disease Control and Prevention and other government organizations. Correlation and multiple regression analysis were used to examine the factors influencing smoking rates. For the purpose of investigating regional variations, we employed a decision tree model. The study has found that the significant factors associated with geographical variations in the smoking rates were the rate of hazardous drinking, the completion rate of hypertension education, the experience rate of anti-smoking campaigns, stress awareness rate, hypertension prevalence, health insurance cost, diabetes prevalence, obesity rate, and strength training rate. Convergence-based analysis on geographical variations of the smoking rates is highly important when the regionally customized healthcare programs is implemented. In the future, it is necessary to develop effective program and customized approach for the regions of high smoking rates. Our study is expected to be used as meaningful data for the design of effective health care programs and assessments to lead effective non-smoking program.

• Journal of the Korea Concrete Institute
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• v.22 no.4
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• pp.575-583
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• 2010

This research investigated the influence of the number of twist on single fiber pullout behavior of Twisted steel (T-) fiber and tensile behavior of high performance cementitious composites reinforced with the (T-) fibers (HPFRCC). Micromechanical pullout model for T- fibers has been applied to analytically investigate the influence of various fiber parameters including the number of twist on single fiber pullout behavior; and, to optimize the number of twist to generate larger pullout energy during fiber pullout without fiber breakage. In addition, an experimental program including single fiber pullout and tensile tests has been performed to investigate the influence of twist ratio experimentally. Two types of T- fiber with different twisted ratios, T(L)- fiber (6ribs/30 mm) and T(H)- fiber (18ribs/30 mm), were tested. T(L)- fiber produced higher equivalent bond strength (larger pullout energy) although T(H)- fiber produced higher pullout stress during pullout since T(H)- fiber showed fiber breakage during pullout. Tensile test results confirmed that T(L)- fiber in high strength mortar generates better tensile performance of HPFRCC, e.g., load carrying capacity, strain capacity and multiple micro-cracking behavior.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.19 no.2
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• pp.102-105
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• 2009

The accelerated life time test of the MLCCs with different $BaTiO_3$ particle sizes were conducted at $150^{\circ}C$, 75 V condition and the effect of $BaTiO_3$ particle size on the breakdown voltage and degradation characteristics of MLCCs was investigated. The MLCCs were prepared by using the $BaTiO_3$ particles having the size of $0.525{\mu}m$, $0.555{\mu}m$, $0.580{\mu}m$ and Ni-electrode, respectively. The MLCCs which have the particle size of $0.525{\mu}m$, $0.555{\mu}m$, and $0.580{\mu}m$, respectively were confirmed to meet the standard requirements of X5R(change capacitance within ${\pm}15%$ at $-55{\sim}85^{\circ}C$) by TCC(Temperature Coefficient of Capacitance). The effect of the $BaTiO_3$ particle size on the insulation resistance behavior of MLCCs was confirmed by BDV(Breakdown Voltage) measurements and the cause and degree of degradation of MLCCs were characterized by XPS analysis after the accelerated life test. The MLCCs with $0.525{\mu}m-BaTiO_3$ showed better insulation resistance and BDV characteristics compare to other MLCCs and XPS analysis revealed that the MLCCs degradation is caused by the NiO peak and $BaTiO_3$ peak decrease.

• Journal of Korean Public Health Nursing
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• v.15 no.2
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• pp.225-238
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• 2001

The purpose of this study is to examine public health nurses for their morale, test the effect of each factor on the morale, determine the variables affecting the morale, and thereby, provide for some basic data useful to the development of personnel affair administration for nurses. The survey on the nurses for public health centers was conducted for 10 days from April 23 to May 2, 2001; 96 nurses from Pusan, 101 from Kyonggi-do and 108 from Kangwon-do. The results of the study are as follows; 1. For the demographic variables, those aged between 31 and 39 accounted for the majority $(50.2\%)$ of the sample. $90.8\%$ was married, and $67.9\%$ of the sample graduated from junior colleges. $29.6\%$ of them had worked for 10-14 years and $62.5\%$ was of the seventh rank. $62.3\%$ of the nurses was recruited, and $59.4\%$ had chosen the public job for its guaranteed status. Half the nurses were working for the county population of which was more than 260 thousands, and $53\%$ of the nurses was serving the public health centers with 11-15 members. $47.3\%$ of them perceived that their living standard is middle or lower. 2. The degree of the moral was found as mean score. 2.65, which is interpreted as low. It has 11 factors. The rank of mean score of the factors is job satisfaction (3.36), sense of belonging (3.36), sense of recognition (3.30), stress due to supervision (3.13), degree of participation (3.05) and self-achievement (3.04), while those scoring lower points were assurance of status (2.58), pay level (2.53), working conditions (2.35) and promotion opportunity (2.31). 3. The degree of moral depending on the demographic variables was significantly affected by such variables as age. academic background, career, rank, employment method, motive for the job, size of the population served and living standards. 4. The result of the Stepwise multiple regression analysis for the morale factors, it was found that self-achievement accounted for $61\%$ of the total variance of the degree of morale, followed by stable status $(18\%)$, working conditions $(8\%)$, job requirements $(4\%)$ and promotion opportunities $(2\%)$; these five factors explained about $94.6\%$ of total variance of the degree of nurses' morale. On the other hand. age $(8\%)$ and academic background $(2\%)$ accounted for $10\%$ of the total variance of the degree of morale. 5. The factors affecting nurses' job life was economic need $(26.7\%)$, personnel management $(17.5\%)$, sense of recognition $(13.2\%)$, human relationship $(11.0\%)$, stable status and personal development in rank. On the other hand, the factors influencing on their possible resignation were children's bringing-up $(27.8\%)$, poor personnel management and promotion $(13.3\%)$, workload $(11.1\%)$ and little personal development $(8.9\%)$, Since such morale factors as promotion opportunity, working condition. pay level and stable status scored lower, it is required to reconsider those factors to improve nurses' morale.

• Journal of Korean Public Health Nursing
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• v.15 no.2
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• pp.262-274
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• 2001

This study was undertaken to grasp the relationship between perceived health status, health conception and health promoting behavior in the elderly. The subjects for this study were 157 old persons in Kyung-ju city. Data were collected by interview with questionnaires from August 24 to October 10, 1999. Analysis of the data was done by SPSS program using descriptive statistics, t-test, ANOVA, Pearson Correlation Coefficient, stepwise multiple regression. The results were summarized as follows 1. For the practice of health promoting behavior. the mean score was 2.52. The factor of the highest mean score was nutrition(3.02) and factor of the lowest mean score was exerciset(2.03). 2. According to age(F=3.35, P=.012), sex(t=2.26, P=.025), marital status (F=5.08, P=.007), education(F=4.22, P=.003), family numbed(F=5.31, P= .006), people living together (F=2.77, P=.044), economic status(F=7.10, P=.00l), average monthly pocket money (F=3.35, P=.012), there were differences of health promoting behavior. 3. According to age(F=3.40, P=.01l), sex(t=4.30, P=.000), education(F=8.55, P=.000), economic status(F=12.59, P=.000), average monthly pocket money(F=4.26, P=.003), present disease(t=-8.41, P=.000), there were differences of perceived health status. According to marital status(F=3.36, P=.037), education(F=2.89, P=.038), there were differences of health conception. 4. Performance in the health promoting behavior was significantly correlated with perceived health status(r=.272, P=.00l), health conception(r=.345, P=.000) 5. The combination of well-being health conception and average monthly pocket money explained $24.7\%$ of the variance of health-promoting behavior. On the basis of the above findings the following recommendations are made; Nursing interventions enhancing exercise or activity, accountability for health, stress management of the elderly must be provided. And Cost-effective health promoting program for the elderly must be developed.

• Journal of Environmental Health Sciences
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• v.46 no.1
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• pp.103-109
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• 2020

Objectives: Using as a sleep evaluation tool the Pittsburgh Sleep Quality Index (PSQI), this paper studied the effects of earthing on the amount and quality of sleep by examining a patient population of people who used and did not use earthing mats and a group of general healthy people. Methods: From September to November 2019, 30 patients who voluntarily used an earthing mat, 40 patients who did not use an earthing mat, and 40 healthy people who did not use an earthing mat were selected. A questionnaire applying the PSQI (Pittsburgh Sleep Quality Index) after being translated into Korean was distributed starting November 29, 2019 to 110 subjects. Out of them, 101 subjects who completed the questionnaire were examined. All statistics used SPSS 25.0. Results: The first overall score showed that all three groups had problems sleeping, with five points or more, but the general population had better sleep quality than the patient group. It also showed that the using matgroup had better quality of sleep than the ones that did not use the earthing mat In addition, the analysis of the third group through the variance analysis showed significance at >0.05 for the general population and the patient group. Based on this, a multi-comparison analysis of the third group showed significantly less than 0.05 in patients who do not use an earthing mat compared to the public. First of all, there are no statistically significant differences between the three groups in subjective sleep quality, sleep latency, and sleep time, but an analysis of multiple comparison analysis with the general population group showed that the quality of sleep was worse compared to those that used the mat. In addition, sleep efficiency, sleep disorder, sleeping pills, and daytime dysfunction were found to be less than >0.05 in the three groups. Conclusions: These results suggest that if you ground your body to Earth during sleep, the secretion of cortisol will decrease night levels, sync more with the natural 24-hour circulation rhythm profile, and that when you sleep, sleep is better and pain and stress are associated with the study. While the preceding study cannot confirm that contact with the ground affects the quality of sleep, it suggests that it is relevant as shown in this paper.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.7 no.1
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• pp.135-144
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• 2012

The purpose of this research study is to find factors associated with burnout in social workers in public sector. This study examined the impact of social support and job-related tension on burnout of social workers in public sector. A participant of 300 social workers in public sector were recruited from Inchen city and completed the questionnaires during August, 2011. Data were entered into simple regression and hierarchical multiple regression analyses. First, women had a little higher mean score of burnout than men. However, this was not a statistically significant difference. Job Classification and year of work experiences were very important predictors for burn-out of social workers in public sector. Second, there was a strong positive relationship between job-related tension and burnout. Third, there was a strong negative relationship between social support and burnout. As the perception about social support by social workers increased, the level of burnout tended to decrease. Finally, the set of analyses examined the impact of social support after controlling for effects of demographic variables and job-related tension. Perceived social support, job-related tension made a significant contribution in burnout. The results of this research study provide several implications for social work practices. More research is needed regarding the effects of social support and job-related tension on burnout of social workers in public sector. For social works in public sector, supervision from supervisors appeared to have a protective effect against social workers' burnout.

• ALGAE
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• v.35 no.3
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• pp.253-262
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• 2020

Haematococcus pluvialis is a commercial microalga that can produce high quantities of astaxanthin. Under induced conditions, some important changes in the subcellular structures related to astaxanthin accumulation were observable. For example, a large number of astaxanthin granules, oil structures and starch granules appeared in the thick-walled cells; Astaxanthin granules gradually dissolved into the oil structures and spread throughout the entire cell with the fusion and diffusion process of oil structures during the middle and late stages of induction; The plastoglobules were closed to the newly formed structures, and some plastoglobules would abnormally increase in size under stress. Based on observations of cell damage, the degradation of membrane structures, such as chloroplasts, was found to be the primary form of damage during the early stage of induction. During the middle stage of induction, some transparent holes were exposed in the dissolving astaxanthin granules in the cytoplasm. In thick-walled cells, these transparent holes were covered by oil substances dissolving astaxanthin, thereby avoiding further damage to cells. Given the relatively few oil structures, in non-thick-walled cells, the transparent holes expanded to form multiple transparent areas, eventually resulting in the rupture and death of cells. These results suggested that the high level of synthesis and the wide range diffusion of oil explained the expansion of astaxanthin in H. pluvialis.

• Journal of Life Science
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• v.28 no.6
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• pp.639-647
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• 2018

A new heat shock protein 70 was identified in red-spotted grouper (Epinephelus akaara) based on an expression analysis. The cDNA of red-spotted grouper Hsp70 (designated RgHsp70) was cloned by the rapid amplification of cDNA ends (RACE) techniques. The full-length of RgHsp70 cDNA was 2,152 bp, consisting of a 5'-terminal untranslated region (UTR) of 105 bp, a 3'-terminal UTR of 274 bp, and an open reading frame (ORF) of 1,773 bp that encode a polypeptide of 590 amino acids with a theoretical molecular weight of 64.9 kDa and an estimated isoelectric point of 5.2. Multiple alignment and phylogenetic analyses revealed that the RgHsp70 gene shares a high similarity with other Hsp70 fish genes. RgHsp70 contained all three classical Hsp70 family signatures. The results indicated the RgHsp70 is a member of the heat shock protein 70 family. RgHsp70 mRNA was predominately expressed in the liver, with reduced expression noted in the head-kidney tissues. The expression analysis of different water temperatures (21, 18, 15 and $12^{\circ}C$) for sampled livers revealed that expression gradually increased at $12^{\circ}C$ compared to $21^{\circ}C$. In this study, the effects of water temperature lowering on the physiological conditions were investigated, and the results revealed that novel RgHsp70 may be an important molecule involved in stress responses.