• Journal of Korea Water Resources Association
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• v.53 no.2
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• pp.107-119
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• 2020

This study analyzed past drought characteristics based on the observed rainfall data and performed a long-term outlook for future extreme droughts using Representative Concentration Pathways 8.5 (RCP 8.5) climate change scenarios. Standardized Precipitation Index (SPI) used duration of 1, 3, 6, 9 and 12 months, a meteorological drought index, was applied for quantitative drought analysis. A single long-term time series was constructed by combining daily rainfall observation data and RCP scenario. The constructed data was used as SPI input factors for each different duration. For the analysis of meteorological drought observed relatively long-term since 1954 in Korea, 12 rainfall stations were selected and applied 10 general circulation models (GCM) at the same point. In order to analyze drought characteristics according to climate change, trend analysis and clustering were performed. For non-stationary frequency analysis using sampling technique, we adopted the technique DEMC that combines Bayesian-based differential evolution ("DE") and Markov chain Monte Carlo ("MCMC"). A non-stationary drought frequency analysis was used to derive Severity-Duration-Frequency (SDF) curves for the 12 locations. A quantitative outlook for future droughts was carried out by deriving SDF curves with long-term hydrologic data assuming non-stationarity, and by quantitatively identifying potential drought risks. As a result of performing cluster analysis to identify the spatial characteristics, it was analyzed that there is a high risk of drought in the future in Jeonju, Gwangju, Yeosun, Mokpo, and Chupyeongryeong except Jeju corresponding to Zone 1-2, 2, and 3-2. They could be efficiently utilized in future drought management policies.

• Journal of Digital Convergence
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• v.16 no.3
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• pp.249-259
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• 2018

This research had intended to find out regarding the present influences of the Smart Work on the intention to use continuously with the staff members working in the small- and medium-sized enterprises as the subject. And, finally, it had intended to find out about the Smart Work environments of the IT corporations and the non-IT corporations. For this research, the questionnaire survey data were collected from the staff members working at the small- and medium-sized enterprises. Through the questionnaire survey data that were collected, an empirical analysis was carried out. And, through the reliability analysis, the feasibility analysis, the discriminatory feasibility analysis, and the inspection of the degree of suitableness of the structural equation model, finally, the research model was verified and, finally, a difference analysis of the IT corporations and the non-IT corporations was carried out. Regarding the results of the analysis of the research, it appeared that the factors of the job efficiency and the job autonomy of the special characteristics of the job had the positive influences on the usefulness and the job satisfaction, which were the parameters and which were perceived. And it appeared that the time flexibility of the job form could not have any influences on the usefulness and the job satisfaction, which were the parameters and which were perceived. And it appeared that the spatial flexibility had the influences on the job satisfaction only. The perceived usefulness, which was a parameter, had the positive influences on the job satisfaction and the intention to use continuously. And, finally, the job satisfaction had the positive influences on the intention to use continuously. And it appeared that there were the differences, too, between the IT corporations and the non-IT corporations. It is thought that, through the results of this research and through the Smart Work environment, the positive influences on the workers and the organizations could be induced and that a better working environment than previously can be provided to the workers to fit the special characteristics of the corporations.

• Korean Journal of Environment and Ecology
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• v.34 no.4
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• pp.334-344
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• 2020

A total of 24 families, 44 species, and 658 benthic macroinvertebrates were identified, and Ecdyonurus dracon Kluge (13%) was the dominant species in forested streams within the Yeonyeopsan (Mt.). A total of four habit categories (i.e., clingers (56%), burrowers (19%), swimmers (14%), and sprawlers (56%)) were identified, and clingers were the dominant habit at all survey points except point one (UP1). Habitat characteristics were depended on the hydraulic factors (e.g., flow velocity, depth, and substrates), water quality (e.g., DO and water temperature), and the habitat characteristics were differed in the riffle, which has a faster the flow velocity, compared by in the stagnant pool. In other words, in riffles, the clingers dominated in high flow velocity with the large maximum and median grain size for substrates in the habitats regardless of depth, but the burrowers and sprawlers were dominant in low flow velocity with the small maximum and median grain size for substrates in the habitats. Moreover, DO and flow velocity were in positive correlation (y = 0.6666x - 0.659, R² = 0.0851), and the habitat for burrowers was wider than that for sprawlers or clingers. The water depth was negatively correlated with water temperature (y = -26.397x + 283.87, R² = 0.1802) since the water temperature is more sensitive to insolation in shallow depth. pH was positively correlated with water temperature. The investigation of the habitat characteristics by separating the relations between pH and DO in upstream and downstream showed the low pH and high DO in the upstream with a high crown density of 68%, regardless of community composition. On the other hand, high pH and low DO in the downstream with a relatively low crown density of 51%. It was considered that the riparian forest played a role in suppressing the growth of attached algae and the controlling water temperature in headwater streams. Our findings identified the habitat characteristics of benthic macroinvertebrates in a headwater stream. We expected that the finding can provide reference data for suggesting conservation and management plans in a headwater stream and increasing academic value.

• Journal of Home Health Care Nursing
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• v.4
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• pp.30-40
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• 1997

The change in health care environment increases the importance of Visiting Nursing Services Program. It has been performed by nurses of district health centers in Seoul since 1991. The Achievement of Visiting Nursing Services Program will be dependent upon their activities. The purpose of this study was to identify the Performance of Visiting Nurses and Job satisfaction of district health centers in Seoul. Therefore, it was to provide the fundamental data development of Visiting Nursing Services Program. The subjects were 214 Visiting Nurses of district health centers in Seoul. The data was collected by self reporting questionnaire from April 15 to April 30, 1997. Their performances and various supportive factors were measured with the instruments developed by the researcher. Job satisfaction were also measured by the instrument developed by Slavitt et al. (1978) was used. The data were, analyzed by Cronbach Alpha, mean, standard deviation, percentage, t -test, ANOVA Duncan test, Correlation Coefficient, and Stepwise Multiple Regression with SAS program. The results of this study were as follows: 1. The average of budget of Visiting Nursing Services Program of district health centers was 0.9% and the average of visiting nursing services personnel of district health centers was 10.1%. 2. With regard to the job satisfaction of Visiting Nurses the mean score was 2.92 out of 5. While the level of Job prestige / status presented as a mean score of 3.48 which was the largest among the 7 components of job satisfaction, the level of administration was the lowest showing 2.57 scores respectively. There were significant differences in the job satisfaction by age, working career of health centers(p<0.01, 0.001). 3. The average of the performance level of Visiting Nurses variables was 2.29; The variable with highest degree of performance was the teaching & consultation, establishment of performance plan, whereas the on with the lowest degree was the directive nursing services. The significant difference was found in performance level according to age, structure type of visiting nursing services, working career of health centers and working career of visiting nursing services(p<0.05). 4. With regard to the perception of the performance expertise by the Visiting Nurses the mean score was 2.37 : The variable with highest degree of performance expertise was the teaching & consultation, establishment of performance plan, whereas the on with the lowest degree was management of home-environment. The significant difference was found in performance expertise according to working career outside of health centers(p<0.05). 5. With regard to the perception of the performance necessity by the Visiting Nurses the mean was 2. 40 : the variable with highest degree of performance necessity was the teaching & consultation, establishment of performance plan, whereas the on with the lowest degree was directive nursing services. The significant difference was found in performance necessity according to working career of visiting nursing services(p<0.05). 6. A positive correlation was found between job satisfaction and performance level(r=.3731, P<0.001). Also, a weak positive correlation was found between the components of job satisfaction and performance level. 7. Stepwise multiple regression analysis revealed that the most powerful predictor was the variance of job satisfaction(R=.3557, $R^2$=.1265). Structure type of visiting nursing services and working career of visiting nursing services accounted for 19.0% of the variance in performance level in nurses. In conclusion, Job satisfaction, Structure type of visiting nursing services and Working career of visiting nursing services variables had influenced on performance level in health centers. Further research is required to confirm these findings.

• Journal of The Korean Association For Science Education
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• v.37 no.6
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• pp.937-949
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• 2017

In this study, we investigated how science teachers perceive the changes in school systems, including infrastructure and curriculum, in the context of preparing for future education. And the changes in their perception of the educational environment, the challenges, and changes of science teachers' classroom practices were also explored. In-depth interviews and analysis were conducted with two science teachers in a middle school that is trying to innovative on changes compared with general schools. The results of the study are as follows: First, teachers perceived that their schools had factors that could change the science class in terms of school size and infrastructure, peer teacher culture, and students' abilities. Second, the enthusiasm of teachers who are trying various ways of teaching and the students' ability to adapt in a smart learning environment formed a synergistic circle that lowered entry barriers to trying changes. Third, science classes changed to activity-centered classes, and teachers realized that these changes promoted students' self-directed learning. Fourth, teachers perceived themselves as playing an independent role in curriculum management, and this perception promoted more varied attempts in improving their classes. Through the changes of the learning environment and systems of the school and the formation of a culture that shares their challenges and innovations with the voluntary learning community, teachers constantly try to change their classes and schools. The changes of school need to be understood in the context of the interaction of teachers, students, and infrastructure.

• Tuberculosis and Respiratory Diseases
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• v.47 no.2
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• pp.231-238
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• 1999

Background: Nocturnal hypoxemia occurs in patients with chronic obstructive pulmonary disease(COPD) and the detection and treatment of nocturnal hypoxemia should be part of the management of COPD patients. We performed this study to evaluate the factors influencing to sleep related arterial oxygen desaturation($SaO_2$) in patients with COPD. Methods: Resting and exercise cardiopulmonary function test, polysomnography, and $SaO_2$ during resting, exercise and sleep were measured in 12 patients with COPD. Results: The $SaO_2$ fell twice as much during sleep as during maximal exercise($13.1{\pm}9.3%$ fall in nocturnal $SaO_2$ vs. $6.4{\pm}3.3%$, p<0.05). Fall in nocturnal $SaO_2$ was well correlated with mean exercise $SaO_2$(r=-0.78, p<0.05), minimum exercise $SaO_2$(r=-0.90, p<0.01), and resting $SaO_2$(Cr=-0.82, p<0.05). Lowest sleep $SaO_2$ was well correlated with mean exercise $SaO_2$(r=0.80, p<0.05), lowest exercise $SaO_2$(r=0.90, p<0.01), and resting $SaO_2$(r=0.84, p<0.05). Conclusion: Resting and exercise $SaO_2$ was well correlated with nocturnal $SaO_2$, but exercise study add no additional information to predicting the nocturnal oxygen desaturation in patients with COPD.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.5
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• pp.561-570
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• 2008

This study aimed to determine the effects of freeze-dried onion powder (OP) which contains rich in quercetin (22 mg/10 g) on hyperlipidemic participants. Fourteen participants (total cholesterol level in plasma $270.8{\pm}21.4mg/dL$) $40{\sim}59$ years of age who were diagnosed as hyperlipidemia by a physician at Fatima Hospital in Changwon took part in this study for 12 weeks. We investigated the anthropometric data and dietary habit by using questionnaires. Also, blood samples were collected from the patients in fasting before and after this 12 weeks intervention study. 78.6% of the patients showed interest in health diet management and weight control; however, they also showed some problems in their dietary habit (meal irregularity, food choice, calorie nutrient balance, high fat and cholesterol etc.) and life style (smoking, eating out, alcohol intake) that could have adverse effect on hyperlipidemic therapy. Most participants (85.7%) thought that OP was good for their health. The total cholesterol and LDL-cholesterol significantly decreased with OP intake. The HDL-cholesterol increased and the Atherogenic index (AI) significantly decreased. Regarding the correlations of dietary habit and life style with anthropometric and biochemical factors, the alcohol intake level was significantly correlated with the frequency of eating out and body mass index (BMI). Exercise level showed positive correlation with HDL-cholesterol and negative correlation with atherogenic index (AI). These results suggest that the intake of polyphenol rich onion may decrease the risk of hyperlipidemia by reducing cholesterol level. We consider these hypolipidemic effects of OP as a possible functional food. However, further research such as a well designed longterm clinical study with experimental and placebo groups is needed.

• Journal of Korean Society of Forest Science
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• v.70 no.1
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• pp.1-6
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• 1985

The purpose of this experiment lies in finding the most appropriate cutting condition of Taxus cuspidata Sieb. et Zucc. which has been considered valuable tree species in gardening. Statistical analysis was focused on the comparison of the average ratios of rooting between greenhouses and fields, based on the observation rooted autogenis. To conduct this survey, hardwood cutting of Taxus cuspidata Sieb. et Zucc. were performed at both places of experiment above on April 20, 1982 with rooting results calculated on October 31, 1982. After formation of cuttings, it was soaked in IBA 200 ppm for 12 hours and than put in a bed. A summary of the result is presented as follows; 1) Cutting at the greenhouse showed higher average rate of rooting than at fields. Same tendency was found regardless of the differences in treatment. 2) It was clear that IBA-treatment contributed remarkably to causing higher average rooting rate. As an evidence, when twenty centimeter cuttings were inserted sandy media, IBA-treated area resulted in eighty six percent of average rooting rate, as compared with only twenty three percent in nontreatment case. In case of field cutting, IBA-treatment brought about fifty three percent of rooting in comparison with eleven percent nontreatment. 3) When sandy soil, loam and brown soil were separately used as cutting media, the highest rooting rate was found in case of sandy soil, without any difference between the two experimental places above. 4) As a result of the analysis to seek the impact of the length of cuttings on rooting, the range of length form fifteen to twenty centimeter was apparently most appropriate. It was also found that the rate of rooting declined beyond twenty five centimeter. 5) Two kinds of rooting pattern were observed. One was the case that callus cell lump was created on the lower cut side of cuttings. Importantly, root radical were formed inside the lump to influence the germination of root system. The other relates to the case that adventitious root which look like lateral roots appeared at the stem region. In abstract, first, sandy soil was effectively recommended in case of hardwood cutting in April. Second, the most appropriate length of cuttings ranged between fifteen and twenty centimeters. Third, high density IBA treatment was clearly effective. Forth, for proper environmental management, both pre-disinfection of sail by sterilizer and maintenance of high relative humidity were essentially required.

• Journal of Global Scholars of Marketing Science
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• v.19 no.2
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• pp.17-26
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• 2009

As the lifestyle of consumers changes and the need for various products increases, new products are being developed in the market. Each household owns various home appliances which are purchased through the choice of a decision maker. These appliances include not only large-sized products such as TV, refrigerator, and washing machine, but also small-sized products such as microwave oven and air cleaner. There exists latent correlation among possession of home appliances, even though they are purchased independently. The purpose of this research is to analyze the effect of demographic factors on the purchase and possession of each home appliances, and to derive some relationships among various appliances. To achieve this purpose, the present status on the possession of each home appliances are investigated through consumer survey data on the electric and energy product. And a multivariate probit(MVP) model is applied for the empirical analysis. From the estimation results, some appliances show a substitutive or complementary pattern as expected, while others which look apparently unrelated have correlation by co-incidence. This research has several advantages compared to previous literatures on home appliances. First, this research focuses on the various products which are purchased by each household, while previous researches such as Matsukawa and Ito(1998) and Yoon(2007) focus just on a particular product. Second, the methodology of this research can consider a choice process of each product and correlation among products simultaneously. Lastly, this research can analyze not only a substitutive or complementary relationship in the same category, but also the correlation among products in the different categories. As the data on the possession of home appliances in each household has a characteristic of multiple choice, not a single choice, a MVP model are used for the empirical analysis. A MVP model is derived from a random utility model, and has an advantage compared to a multinomial logit model in that correlation among error terms can be derive(Manchanda et al., 1999; Edwards and Allenby, 2003). It is assumed that the error term has a normal distribution with zero mean and variance-covariance matrix ${\Omega}$. Hence, the sign and value of correlation coefficients means the relationship between two alternatives(Manchanda et al., 1999). This research uses the data of 'TEMEP Household ICT/Energy Survey (THIES) 2008' which is conducted by Technology Management, Economics and Policy Program in Seoul National University. The empirical analysis of this research is accomplished in two steps. First, a MVP model with demographic variables is estimated to analyze the effect of the characteristics of household on the purchase of each home appliances. In this research, some variables such as education level, region, size of family, average income, type of house are considered. Second, a MVP model excluding demographic variables is estimated to analyze the correlation among each home appliances. According to the estimation results of variance-covariance matrix, each households tend to own some appliances such as washing machine-refrigerator-cleaner-microwave oven, and air conditioner-dish washer-washing machine and so on. On the other hand, several products such as analog braun tube TV-digital braun tube TV and desktop PC-portable PC show a substitutive pattern. Lastly, the correlation map of home appliances are derived using multi-dimensional scaling(MDS) method based on the result of variance-covariance matrix. This research can provide significant implications for the firm's marketing strategies such as bundling, pricing, display and so on. In addition, this research can provide significant information for the development of convergence products and related technologies. A convergence product can decrease its market uncertainty, if two products which consumers tend to purchase together are integrated into it. The results of this research are more meaningful because it is based on the possession status of each household through the survey data.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.22 no.2
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• pp.206-216
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• 2000

Predictional study for lateral change between pre- and post-orthognathic surgery has been emphasized mainly on anterior area of lateral profile; upper lip, lower lip and chin et al. So interest for lateral profile change has been less in posterior area of lateral profile and literature analyzing gonial angle change is rare. The purpose of this study is to make prediction for gonial angle change possible and to offer somewhat treatment guidance for gonial angle to be improved by investigating overall gonial angle change between pre- and post-orthognathic surgery and inquiring into factors influencing on pattern of genial angle change. For this study 35 patients were selected retrospectively. Lateral cephalometric radiographs were taken in just pre-op time, pod 1 day, pod 1 year. They were analyzed and genial angles were measured. The results were as follows : 1. Gonial angle at pod 1 day was decreased about $9.3^{\circ}$ than pre-op and gonial angle at pod 1 year was increased about $4.0^{\circ}$ than pod 1 day. So genial angle at pod 1 year was decreased about $5.3^{\circ}$ than pre-op genial angle(p<0.01). 2. Mean pre-op gonial angle was $129.4^{\circ}$, showing significantly high value than normal and mean gonial angle at pod 1 year was $124.1^{\circ}$, showing value near to normal. 3. Mean gonial angle change between pre-op and pod 1 year was decreased about $5.4^{\circ}$ in female and $5.3^{\circ}$ in male. There was no statistically significant difference between male and female(p>0.05). 4. Principal factor influencing on decreased gonial angle in gonial angle change between pre-op and pod 1 year was amount of mandibular setback. 5. Principal factor influencing on increased gonial angle in gonial angle change between pod 1 day and pod 1 year was % horizontal relapse, and it was thought that resorption and bone remodelling on posterior area in mandibular distal segment also were related to increased gonial angle. 6. It is thought that sagittal split ramus osteotomy in mandibular prognathic patients with high value of gonial angle is effective to improvement of gonial angle, and In patients who have normal range of gonial angle and are required with excessive mandibular setback, short lingual cut method, additional resection of posterior margin of distal segment, Obwegeser II method will be considerd. 7. More prudent operation and careful post-op management will be responsible for maintenance of postoperative stable gonial angle.