• Journal of Advanced Navigation Technology
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• v.21 no.4
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• pp.353-358
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• 2017

In order to reduce the size of the previous stepped slot antenna for UWB applications(3.1 ~ 10.6 GHz) to half, an open ended stepped slot antenna is proposed. The proposed antenna consists of a stepped slot etched on the ground plane as radiation part and a microstrip feed-line with rectangular patch on the top plane for wideband impedance matching. The proposed antenna is designed and fabricated on the FR4 substrate with dielectric constant of 4.3, thickness of 1.6 mm and size of $28.5{\times}32mm^2$. The measured impedance bandwidth (${\mid}S_{11}{\mid}{\leq}-10dB$) of the fabricated antenna is 7.99 GHz(3.01~11 GHz) which is sufficient to cover UWB band (3.1 ~ 10.6 GHz). In particular, it has been observed that antenna has a good omnidirectional radiation patterns and high gain over the entire frequency band of interest even though the size of the proposed antenna is reduced to half when compared with the previous antenna.

• International Journal of Fluid Machinery and Systems
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• v.1 no.1
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• pp.1-9
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• 2008

In the first part of the paper, Computational Fluid Dynamics analysis of the combusting flow within a high-swirl lean premixed gas turbine combustor and over the $1^{st}$ row nozzle guide vanes is presented. In this analysis, the focus of the investigation is the fluid dynamics at the combustor/turbine interface and its impact on the turbine. The predictions show the existence of a highly-rotating vortex core in the combustor, which is in strong interaction with the turbine nozzle guide vanes. This has been observed to be in agreement with the temperature indicated by thermal paint observations. The results suggest that swirling flow vortex core transition phenomena play a very important role in gas turbine combustors with modern lean-premixed dry low emissions technology. As the predictability of vortex core transition phenomena has not yet been investigated sufficiently, a fundamental validation study has been initiated, with the aim of validating the predictive capability of currently-available modelling procedures for turbulent swirling flows near the sub/supercritical vortex core transition. In the second part of the paper, results are presented which analyse such transitional turbulent swirling flows in two different laboratory water test rigs. It has been observed that turbulent swirling flows of interest are dominated by low-frequency transient motion of coherent structures, which cannot be adequately simulated within the framework of steady-state RANS turbulence modelling approaches. It has been found that useful results can be obtained only by modelling strategies which resolve the three-dimensional, transient motion of coherent structures, and do not assume a scalar turbulent viscosity at all scales. These models include RSM based URANS procedures as well as LES and DES approaches.

• The Journal of Korean Academic Society of Nursing Education
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• v.8 no.1
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• pp.131-144
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• 2002

The purpose of this study was to measure the knowledge, attitude, experience in sex and the needs of sex education for college students in order to provide basix sex education information for this study, the questionnaires were given to 1,210 women's students in K college of Inchon and collected during the period from June to July, 2001. These results were analyzed statistically by means of frequency, percentage, t-test, ANOVA and regression test. The results of this analysis are as follows: 1. The level of knowledge related to sex was relatively low. The difference of grade was 2nd. grade somewhat higher than 1st. grade and major of public science higher than literature. The scores related to sexual attitude, 45.7% of the respondent answered 'strongly agree' and 'agree' with abortion before marriage, 31.5% of the respondent answered 'strongly agree' or 'agree' with male's responsibility for premarital pregnancy. 2. To solve sexual problems, 48.0% of the respondents intended to consult their friends, 8.5% of the respondents intended to consult expert. 3. The sequence of sexual experience were 7.1% genital coitus, 5.4% masturbation, 4.5% contraceptive, 0.4% veneral disease, 2.6% rape, 2.1% pregnancy. 4. 98.4% of the respondents agreed there was a need for sex education in the college and wanted to acquire information through 45.5% special lecture, 18.0% regular curriculum, within the content of sex education, needs in order to priority are; contraceptive, sexual psychology, pregnancy, veneral disease, sexual morality etc. 5. Regarding sexual knowledge, there were no significant difference grade or major and relationship between sexual attitude and knowledge, respondents who answered 'agree' with premarital coitus had more knowledge of sexual physiology & psychology. 6. Regarding relationships between sexual experiences and knowledge, respondents who had experienced veneral disease.

• Journal of Chest Surgery
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• v.18 no.4
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• pp.623-634
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• 1985

One of the most widely recognized problems in patients with TGA [transposition of the great arteries] after the Senning operation is the occurrence of arrhythmias. From June 1982 through October 1984, 22 patients, 11 with "simple" and 11 with "complex" TGA, underwent correction of TGA by a modification of the Senning operation designed to avoid dysrhythmias. 16 were males and 6 females, with ages ranging from 3 months to 27 months. [mean age 10.8 months] 7 patients [31.8%], 1 with simple TCA and 6 with complex TGA, died in the early post-operative period. The operative mortality was 9.1% in "simple" TGA, and 54.9% in "complex" TGA. There were 4 late deaths but only one of these patients died of a dysrhythmia as a possible factor. The standard ECG [Electrocardiography] checked preoperatively showed sinus rhythm in 17 [77.3%], 1 AV block in 5 [22.7%]. In 22 patients studied postoperative 1st day, the incidence of arrhythmias was 63.6%, with significant incidence compared with preoperative study. [P<0.05]. But, in 15 patients studied postoperatively at intervals from 1 month to 26 months, the incidence of arrhythmias was 26.7%, with no significant incidence compared with preoperative study [P>0.1]. Our results indicate that a modified Senning operation may reduce the frequency of surgically induced arrhythmias. The mean frontal plane P-wave axis also revealed significant deviation to the right side [P<0.05], compared with preoperative study. These findings raise the possibility that what has been called sinus rhythm postoperatively may have a different origin and conduction sequence from normal. But the rhythm seems to be functionally similar.rhythm seems to be functionally similar.

• Nutrition Research and Practice
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• v.10 no.1
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• pp.67-73
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• 2016

BACKGROUND/OBJECTIVES: This study was aimed at examining the association between dietary flavanones intake and lipid profiles according to the presence of metabolic syndrome (MetS) in Korean women with type 2 diabetes mellitus (T2DM). SUBJECTS/METHODS: A cross-sectional analysis was performed among 502 female T2DM patients (non-MetS group; n = 129, MetS group; n = 373) who were recruited from the Huh's Diabetes Clinic in Seoul, Korea between 2005 and 2011. The dietary intake was assessed by a validated semi-quantitative food frequency questionnaire (FFQ) and the data was analyzed using the Computer Aided Nutritional Analysis program (CAN-Pro) version 4.0 software. The intake of flavanones was estimated on the basis of the flavonoid database. RESULTS: In the multiple linear regression analysis after adjustment for confounding factors, daily flavanones intake was negatively associated with CVD risk factors such as total cholesterol, LDL-cholesterol, and apoB and apoB/apoA1 ratio only in the MetS group but not in the non-MetS group. Multiple logistic regression analysis revealed that the odds ratio for a higher apoB/apoA1 ratio above the median (${\geq}0.74$) was significantly low in the $4^{th}$ quartile compared to that in the $1^{st}$ quartile of dietary flavanones intake [OR: 0.477, 95% CI: 0.255-0.894, P for trend = 0.0377] in the MetS group. CONCLUSIONS: Dietary flavanones intake was inversely associated with the apoB/apoA1 ratio, suggesting a potential protective effect of flavanones against CVD in T2DM women with MetS.

• Journal of Korean Biological Nursing Science
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• v.3 no.2
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• pp.1-20
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• 2001

The object of this study was to measure the biocidal effect of povidone on staphylococcus found in tracheal incision site, change following the disinfection frequency and duration, and tolerance to the antibiotics. The data was analysed by percentage and t-test using SAS program. The subjects of this study are 35 tracheostomy patients in and Intensive Care Unite of the hospital located in Daegu city and analysing term was from January 16 to February 26, 2001. The results of this study were as follows. The biocidal effect of povidone on Staphylococcus was strong regardless of time and concentration. Staphylococcus aureus was found on third day and found to be highest concentration on 6th day after disinfection of once/a day. Coagulase negative Staphylococcus was not found from 1st to 3rd day and highest on 4th day after disinfection of once/a day. As to bacteria colonization following the disinfection frequency, twice per day of disinfection was more effective on Staphylococcus aureus than once a day. In tolerance test of Staphylococcus aureus and Coagulase negative Staphylococcus, 72.7% of Staphylococcus aureus showed tolerance in Methicillin, 63.6% in Imipenem, and 37.5% of Coagulase negative Staphylococcus showed tolerance in Methicillin, 12.5% in Imipenem. Both of them do not have any tolerance in Vancomycin. The results of this study can be used as the basis for protection against hospital mediated infection through thorough disinfection. With above results, I suggest the following. First, we should research relation between antiseptics and fungi, virus more deeply. Secondly, all medical personnel should try to protect against the hospital medicated infection. Thirdly, there is a need of training professional disinfection personnel for preventing hospital mediated infection and the progress of nursing science.

• Korean Journal of Ecology and Environment
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• v.44 no.2
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• pp.187-194
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• 2011

This study analyzed the A1B climate change scenario provided by National Institute of Meteorological Research (NIMR), Korea, to investigate potential climate changes in watersheds of 15 multi-purpose dams in South Korea. The A1B climate change scenario is produced by Regional Climate Model (RCM) with 27 km horizontal grid spacings using a one-way nesting technique with Global Climate Model (GCM). Relative to present climate conditions (1971~ 2000), the modeled 10-year averaged daily temperatures at the watersheds of the 15 multi-purpose dams continuously increased to year 2100, whereas precipitation changes were varied regionally (north, central, and south regions of South Korea). At two watersheds located in Gangwon-province (north region), the modeled temporal variations of precipitation rapidly increased in the 2090's after a slow decrease that had occurred since the 2050's. At seven watersheds in the central region, including Gyeongsangbuk-province to Jeollanam-province, the modeled temporal variations of precipitation increase showed 10-year periodic changes. At six watersheds in the south region, the modeled temporal variations of precipitation increased since the 2070's after a rapid decrease in the 2060's. Compared to the climate conditions of the late of 20th century (1971~2000), the number of rainy days and precipitation intensity increased (3% and 6~12%, respectively) in the late 21st century (2071~2100). The frequency of precipitation events tended to increase with precipitation intensity in all regions. The frequency of heavy precipitation events (>50 mm $d^{-1}$) increased with >100% in the north region, 60~100% in the central region, and 20~60% in the south region.

• Journal of Science Education
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• v.39 no.3
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• pp.343-357
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• 2015

The present study aims to analyze the extent of the use of STS contents in the areas of 'Evolution of Life' and 'Health of Humanity and Scientific Technology' in 'Science' textbooks and to determine whether they meet the goals of the curriculum revised in 2009. The analysis of the 7 types of textbooks according to the STS topics areas indicated big differences between textbooks as little as 16.67% and as much as 58.33%. Also, among the topics associated with STS, 'Space Development and National Defense' and 'Environmental Problems' were not included. In the STS activity areas, the areas of 'Structured Debate,' 'Interpretation of Data,' 'Research and Investigation' showed great frequency. On the other hand, the STS activity areas of 'Field Activities,' 'Problem-solving and Decision-making,' 'Role Playing,' 'Simulation,' 'Case Study,' and 'Research Design' showed small frequency. Analysis of the STS contents for each area indicated 67.57% for the contents relevant to 'the applicability of science' accounting for the largest part whereas 'Understanding of Occupations related to Science' accounted for 1.63%, showing a great difference in their frequency. Seven standards except 'the applicability of science' were included each contents beyond 10% or less than 10% proportion. The STS contents included in the life science area of the 7 types of convergence-style 'Science' textbooks for the high-school accounted for an average of 20.75%, from as little as 12.35% to as much as 26.90%, depending on the publishes.

• Korean Journal of Community Nutrition
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• v.19 no.2
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• pp.198-211
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• 2014

Objectives: To investigate the use frequency and amount of food sources of sodium and knowledge requirement, and job satisfaction with school food services according to the school types in Busan. Methods: A total of 98 schools were surveyed and knowledge requirement and job satisfaction were assessed using a questionnaire. In addition, the use frequency and amount of food sources of sodium for 10 school days were examined. Results: The response rate of the most difficult area among dietitians' tasks was significantly high in 'nutrition education and counseling' for elementary schools and 'hygiene management' for high schools (p < .05). The response rate of the factors to be considered in meal planning was significantly high in 'energy and nutrients requirement' for elementary schools and 'menu/taste preference of students' for middle and high schools (p < .05). The response rate of whether school food services affect health and eating habits of students or not was significant high in 'very helpful' for elementary schools (p < .001). The average sodium contents in the meals of elementary, middle and high schools was 1981.4 mg/meal/person/day, 1867.3 mg/meal/person/day and 1,329.9 mg/meal/person/day, respectively. For foods in highest sodium, Kimchi, Oribulgogi, and Kare rice were ranked 1st, 2nd and 3rd respectively. The main reason for not providing the fruits was 'price' among all groups. The knowledge requirement such as 'nutrition and menu management', 'nutrition education', and 'nutrition counseling' was significantly higher in elementary school compared with middle and high school (p < .001, p < .01, and p < .01 respectively). The dietitians and nutrition teachers of elementary schools have a higher job satisfaction compared with those of middle schools (p < .01). The job satisfaction was positively correlated with knowledge requirement of dietitians and nutrition teachers of elementary and middle schools. Conclusions: The results suggest that developing dietitians' education program about knowledge requirement contribute to increasing the school food service and job satisfaction in elementary and middle schools.

• Journal of the Korean Child Neurology Society
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• v.26 no.4
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• pp.263-268
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• 2018

Purpose: Obesity and headache are two highly prevalent diseases both in childhood and adolescent. In this study, we assessed the prevalence of obesity in pediatric headaches patients in a single institution in Korea, and differences according to age, sex, headache type, frequency, intensity, and disability. Methods: We retrospectively reviewed the medical records of 340 subjects (6-18 years of age) who visited the Pediatric Headache Clinic of Bucheon St. Mary's Hospital during the period from January 2015 through March 2018. Data on age, sex, height and weight, as well as headache type, frequency, intensity and disability, were collected. Body Mass Index (BMI) percentile was calculated based on the 2017 Korean Children Adolescence Growth Chart. Results: 17.6% of the pediatric headache patients were obese. The prevalence of obesity in male patients was higher than females (Male 23.8% VS Female 11.6%, P=0.002). There were no significant differences in obesity rate according to age, headache type, frequency, intensity, and disability. Conclusion: The prevalence of obesity in the pediatric headache population was 17.6% which is higher than 10.1% in general population (Korea National Health and Nutrition Examination Survey, KNHANES, 2013).