• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2004.03a
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• pp.165-172
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• 2004

LE-7A is the main engine of the H-IIA launch vehicle. Under its development, the nozzle suffered from two troubles during startup and shutdown transients of the engine. One is a large side load, which damages the actuator of the nozzle, and the other is damage on regenerative cooling tubes due to high heat load. It has been considered that these problems are caused by a peculiar separation pattern called Restricted Shock Separation (RSS). RSS is observed in several rocket nozzles, for example, LE-7A nozzle, Vulcain nozzle and so on. Their contours are not conventional truncated perfect (TP) nozzle - LE-7A nozzle is a compressed truncated perfect (CTP) nozzle and Vulcain nozzle is a thrust optimized (TO) nozzle. Although it is believed that the occurrence of RSS is affected by the nozzle contour, the mechanisms are not clarified sufficiently yet. In the present paper, a parametric numerical study is carried out to investigate the mechanisms of the occurrence of RSS in CTP nozzles during startup transient. The results show that RSS is caused by the adverse pressure gradient downstream of the Mach disk. The adverse pressure gradient is caused by the interaction of the pressure wave and Mach disk. The method to avoid the occurrence of RSS is also examined. A small step inside the nozzle affects the position of the separation point and prevents RSS. The result shows that the possibility that RSS can be suppressed by controlling the position of the separation point.

• Journal of Korean Biological Nursing Science
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• v.17 no.1
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• pp.37-43
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• 2015

Purpose: Stress, depending on its intensity and duration, results in either adaptive or maladaptive physiological and psychological changes in humans. Also, it was found that stressful experiences increase the signs of behavioral despair in rodents. On the other hand, exercise and melatonin treatment is believed to have many beneficial effects on health. Thus, this study was designed to evaluate the anti-depressant effects of physical activity and melatonin against chronic stress-induced depression in rats. Methods: Adult male Sprague-Dawley(SD) rats(200-250g, 7 weeks of age) were subjected to depression induced by chronic stress. Chronic depression was induced with forced-swim stress (FSS) and repeated change of light-dark cycle for 4 weeks. In the last 2 weeks, some rats were confined in a cage enriched with a running wheel, seesaw and chewed a ball from 19:00 to 07:00 every day. Melatonin was injected intra-peritoneally (I.P), and the rats received intraperitoneal injections of melatonin (15 mg/kg). The Forced Swim Test (FST) was performed to evaluate the immobility behaviors of rats for a 5 min test. Results: It was found that, the immobility time in FST was significantly (p<.05) lower in physical exercise ($M=58.83{\pm}22.73$) and melatonin ($M=67.33{\pm}37.73$) than in depressive rats ($M=145.93{\pm}63.16$) without physical activity. Also, TPH positive cell in dorsal raphe was significantly (p<.05) higher in exercise ($M=457.38{\pm}103.21$) and melatonin ($M=425.38{\pm}111.56$) than in depressive rats ($M=258.25{\pm}89.13$). Conclusion: This study suggests that physical activity and melatonin produces antidepressant-like effect on stress-induced depression in rats. So, physical exercise and melatonin may be a good intervention in depression patients.

• Publications of The Korean Astronomical Society
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• v.18 no.1
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• pp.97-110
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• 2003

WRC-03 was held between 9 June and 4 July 2003 in Geneva, Switzerland. Over 2,200 delegates from 138 ITU Member States attended the Conference. The delegates considered some 2,500 proposals, and over 900 numbered documents related to 50 agenda items. The final output of the Conference consists of 527 pages of new and revised text of the Radio Regulations. This paper provides some details about the outcome of the radio astronomy related issues at the WRC-03 Conference. It is divided into two part: a) Agenda item1.8.2 and b) Agenda item 1.32, related to radio astronomy. Relevant extracts from the Final Acts of WRC-03 are given in the Appendix. Agenda item 1.8.2 was one of the most controversial Agenda Items at WRC-03. Studies were carried out within ITU-R TG 1/7 for the last three years; the results of these studies are summarized in Recommendation ITU-R SM.1633. The Conference adopted a new footnote (5.347A), that calls for the application of Resolution 739 (WRC-03) in the 1452-1492 MHz, 1525-1559 MHz, 1613.8-1626.5 MHz, 2655-2670 MHz, 2670-2690 MHz and 21.4-22.0 GHz bands. Agenda item 1.32 is to consider technical and reglatory provisions concerning the band 37.5-43.5 GHz, in accordance with Resolutions 128 (Rev.WRC-2000) and 84 (WRC-2000). WRC-03 reviewed and adjusted the New footnotes 5.551H and 5.551I cover the protection of radio astronomy observations in the 42.5-43.5 GHz band from unwanted emissions by non-geostationary (5.551H) and geostationary (5.551I) FSS and BSS systems, respectively.

• The Journal of the Society of Stroke on Korean Medicine
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• v.20 no.1
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• pp.25-32
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• 2019

■ Objectives In this case report, we address a case of a 83-year-old female patient diagnosed with suspicious autoimmune hepatitis. ■ Methods A patient was treated with herbal medication, Injinoryung-san gagam. We evaluated the improvements of symptoms by AST, ALT, GGT, ALP and total score of Fatigue Severity Scale(FSS). ■ Results After 4 weeks of taking Injinoryung-san gagam, there were decrease in abnormal liver enzyme levels with improvement of the patient's fatigue. ■ Conclusion This study suggested that Injinoryung-san gagam might be effective in autoimmune hepatitis patient's liver enzyme levels and fatigue recovery.

• Journal of The Korean Society of Integrative Medicine
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• v.6 no.4
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• pp.1-13
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• 2018

Purpose : The purpose of this study has been performed to find the relationship between seafarers' cumulative fatigue and stress by evaluating autonomic nervous functions and the results of surveys conducted using questionnaires. Methods : The subjects were seafarers working on various ships (home trade ships) of South Korea, who were healthy adults without any diseases, as confirmed through preliminary surveys were recruited through simple random sampling. A device that measures autonomic nervous functions by analyzing heart rate variability, which is also used often in clinical diagnoses and studies at universities, university hospitals, and general hospitals was used to measure the seafarers' cumulative fatigue and stress. Pearson's correlation analyses were also conducted to test the relationship between cumulative fatigue and stress measured by evaluating autonomic nervous functions and the results of surveys conducted with questionnaires. Results : There was no correlation between mean cumulative fatigue measured for each ship type and seafarers position through autonomic nervous functions evaluation and fatigue severity scale (FSS). There also was no correlation between the mean levels of stress measured for each ship type and seafarers position through autonomic nervous functions evaluation and survey scores of Korean occupational stress scale (KOSS). Conclusion : Therefore, in order to prevent man-made accidents in the sea among seafarers working with irregular port entry/departure schedules and under environments involving continued vibration, noises, and shaking, it is necessary to analyzed cumulative fatigue and stress scientifically and objectively, such as through autonomic nervous functions evaluation rather than through surveys.

• Journal of Society of Preventive Korean Medicine
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• v.26 no.3
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• pp.97-108
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• 2022

Objectives : The purpose of this study is to confirm the efficacy and safety of Gongjin-dan and Ssanghwatang for chronic fatigue. Methods : A total of 90 people, between 19 and 65 years old, will be recruited to participate in a randomized, double-blind, and placebo-controlled a clinical trial. Participants in the Gongjin-dan group will take one pill of Gongjin-dan along with three packs of placebo oral liquid Ssanghwa-tang per day for 4 weeks. Participants in the Ssanghwa-tang group will take three packages of liquid Ssanghwa-tang and one placebo Gongjindan pill per day for 4 weeks. In the placebo group, participants will take one pill of placebo Gongjin-dan and three packs of placebo liquid Ssanghwa-tang per day, for 4 weeks. Outcomes will be measured at the baseline, 4^th week, and 6^th week. The primary outcome is the change in the Fatigue Severity Scale (FSS). Secondary outcomes are the change of Multidimensional Fatigue Inventory-20 (MFI-20), Chalder Fatigue Scale (CFQ), Short-Form 36 Health Survey (SF-36), Korean Version of Schedule of Fatigue and Anergy/General Physician (SOFA/GP), Glucose, Lactate, Ammonia, Free Fatty Acid (FAA), d-ROMs&BAP, Selenium, and Cortisol. Results : This trial was approved by the institutional review board of Pusan National University Korean Medicine Hospital (registry number: PNUKHIRB 2021-10-005). Recruitment opened in November 2021 and is supposed to be completed by December 2022. Conclusions : This trial will provide clinical information to determine the efficacy and safety of Gongjindan and Ssanghwa-tang for chronic fatigue.

• Annals of Occupational and Environmental Medicine
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• v.35
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• pp.32.1-32.10
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• 2023

Background: Although many studies have been conducted on worker fatigue and sickness absence, the association between fatigue and sickness absence is unclear in Korean workers. This study was conducted to investigate the effect of worker fatigue on future sickness absence. Methods: The study was conducted on workers who received medical check-ups at a university hospital for two consecutive years (2014-2015). During check-ups in the first year, the Fatigue Severity Scale (FSS) was used to assess fatigue levels, and during check-ups in the second year, sickness absence was surveyed to determine whether they had been absent from work due to physical or mental illness during previous 12 months. The χ² test was used to analyze relationships between sociodemographic and occupational characteristics, fatigue levels, and sickness absence. Odds ratios (ORs) were calculated by logistic regression analysis controlled for confounding factors. Results: A total of 12,250 workers were included in the study, and 396 (3.2%) workers experienced more than one day of sickness absence during the study period. Adjusted ORs for sickness absence were 3.35 (95% confidence interval [CI]: 2.64-4.28) in the moderate-fatigue group and 6.87 (95% CI: 4.93-9.57) in the high-fatigue group versus the low-fatigue group. For men in the moderate- and high-fatigue groups, adjusted ORs for sickness absence were 3.40 (95% CI: 2.58-4.48) and 8.94 (95% CI: 6.12-13.07), and for women in the moderate- and high-fatigue groups, adjusted ORs for sickness absence were 2.93 (95% CI: 1.68-5.10) and 3.71 (95% CI: 1.84-7.49), respectively. Conclusions: Worker fatigue is associated with sickness absence during the following 12 months, and this association appears to be stronger for men than women. These results support the notion that sickness absence can be reduced by evaluating and managing work-related fatigue.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.3 no.1
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• pp.68-74
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• 2000

Purpose: This study was to investigate the clinical manifestations of FTT in children. Methods: From March 1997 to July 1999, clinical observations were made on patients with FTT who had visited to Samsung Medical Center. Detailed histories and through physical examinations were taken, and when suspected organic FTT, basic laboratory studies were done. Results: Upon the review of medical records, we investigated the clinical manifestations of 74 children, aged 1 month and 13 year 1 month. The causes of FTT were composed of either physiologic (47.8%) or pathologic (52.2%) ones. Among the physiologic FTT, were there familial short stature (FSS, 14.5%), intrauterine growth retardation (IUGR, 14.5%), constitutional growth delay (CGD, 11.6%), idiosyncrasy and prematurity. Among pathologic causes, neurologic disorders (20%) are the most common causes of FTT, and then follow by GI (13.4%), allergic and infectious disorders in decreasing order. The data showed that average caloric intake in patients with FTT was 76,2% of recommended amount. FTT patients with CGD, IUGR, and idiosyncrasy had tendency to take small foods. The FTT children with prematurity, IUGR and pathologic FTT, were short and thin for their ages. However FTT children with CGD and FSS had tendency to be thin with relatively normal heights for their ages, in comparison with those of the children with prematurity, IUGR and pathologic FTT. Conclusion: The diagnosis of FTT was easily obtained with simple and through medical history, physical examination, and minimal laboratory tests. In this study, organic FTT was more prevalent than physiologic one. This results indicate that early intervention is mandatory, because children may develop significant long-term sequelae from nutritional deficiency.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.16 no.2
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• pp.177-188
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• 2021

On December 2015, Financial Supervisory Service(FSS) announced the four key thematic audit review areas, one of them is an appropriation of unbilled revenue. Accounting of unbilled revenue is intertwined with a percentage of completion, that is concerned about discretionary decision by manager. Therefore, if manager motivated by income-increasing manipulation is exaggerating percentage of completion, unbilled revenue is excessively recognized. This problem is caused the serious accounting issues(e.g., shock at a loss for 2013 fiscal year by some construction firms, malpractice of accounting in order-made production industry). Distrust of accounting was grown because the shipbuilding and construction industries successively went poor management and bad accounting of them is revealed. Those accounting issues were the trigger for problem recognition of unbilled revenue, they were background for the designation of appropriation unbilled revenue as thematic audit review areas by FSS. Therefore, this study verified effectiveness of thematic audit review by empirically analyzing whether designation of thematic audit review makes the firm increases conservative behavior. Conservative accounting is estimated by using Basu(1997) model. We analyzed the effect of the thematic audit review on conservative accounting of unbilled revenue by comparing with reflecting unbilled revenue or not. The sample for test consists of firm-years the manufacturing and construction industries from 2012 to 2017. The test results of this study suggested that the conservative accounting of unbilled revenue after designation of the thematic audit review was significantly increased. We also tested again by classifying whether or not it is construction industry. We found that construction industry is more conservative than the other industry only for the designated year of the thematic audit review, otherwise there was not any evidence for significantly increasing conservatism. This study contributes to the literature by empirically analysing relationship of the unbilled revenue to the thematic audit review from the perspective of the conservatism and verifying effectiveness of the thematic audit review.

• Vending industry
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• v.3 no.1 s.9
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• pp.64-69
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• 2004

고수익을 미끼로 한 자판기 분양사기가 최근 급증하고 있어 큰 문제가 되고 있다. 무조건 자판기 수익성만을 과대포장하여 투자자들의 `묻지마` 투자를 유도한 후 돈만 챙기고 사업에서 손을 떼어버리는 사기행각은 그 피해대상이 대부분 서민이라는 점에서 문제의 심각성을 더한다. 자판기가 불법 자금 모집을 통해 사기의 대상으로 외부 인식이 악화되어 버린다면 자판기 산업의 입지 역시 크게 좁혀 질 수 밖에 없다. 자판기 품목에 있어서는 불법자금모집의 대표적인 사례가 되는 경우는 확정수익을 보장한다며 투자자를 모집하는 경우이다. 그 후 일정기간동안 수익을 보장하며 투자자를 안심시킨 다음 일순간 돌변하여 자금을 챙겨 잠적을 하는 수순을 밝는다. 선의의 투자자들은 이럴 경우 엄청난 피해를 입게 되는 게 보통이다. 대개의 경우 기계 1~2대의 소량물량이 아닌 5대~l0대 단위의 투자를 유도하기 때문이다. 이제는 자판기 산업에 있어 이러한 악성 불법자금 모집업체들이 근절되어야 한다. 이 불법 사기행각의 대상이 더 이상 자판기 분야에 발을 붙이지 못하도록 하는 제도적 비책이 시급히 강구 되어야 한다. 이러한 가운데 금융감독원 비은행감독국 비제도금융조사팀에서는 올들어 지난 9월말까지 고수익을 미끼로 투자자금을 모집하다가 금감원에 적발된 유사 금융업체 85개사 명단을 사법당국에 통보했다. 불법자금모집 업체들이 투자자들을 유혹하기위해 미끼로 내세운 사업을 종류별로 보면 자판기, 게임기, 컴퓨터단말기 등 특정상품 운영권 제공이 29개사로 가장 많고, 사이버 쇼핑몰 및 인터넷사업(18개사), 납골당 등 부동산 투자(12개사), 영화등 문화 및 레저사업(10개사), 영화문화 및 레저산업(10개사), 벤처투자사(9개사) 등이었다. 자판기 분야에 있어서는 주로 성인용품자판기, 복권자판기 등의 품목이 불법자금 모집의 집중 타킷이 되었다. 금감원은 최근들어 유사 금융업체의 자금모집이 전문가도 속을 정도로 지능화하고 있다며 개인투자자들이 피해를 예방할 수 있는 불법업체 식별법을 금감원 인터넷 사이트(www.fss.or.kr)에 게시했다. 금감원은 특히 사업현황에 대해 지나치게 보안을 유지하는 업체, 1백$\%$이상의 터무니없는 고수익을 보장한다고 광고하는 업체, 제도권 금융회사의 지급보증을 강조하는 업체에 대해서는 투자에 앞서 금감원이나 업종 관련 정부당국에 사실여부를 확인해 보고 투자여부를 결정하라고 통보했다. 아울러 금감원은 금융소비자들이나 자판기 업계에서 불법자금 모집업체를 발견하여 전화(02-3786-8155~9)나 인터넷소비자 보호센터와 경찰에 신고해줄 것을 요청했다. 이제는 산업계도 더 이상 자판기 분야의 불법자금업체를 방치하지 말고 적극적인 금감원 신고를 통해 시장을 정화할 수 있게 해야 한다. 미꾸라지 한두마리가 온 개천 물 다 흐려놓는 이치처럼 자판기불법자금업체들로 인해 전체 산업에 미치는 영향이 실로 심각함을 인식해야 할 때이다. 금호 산업정보에서는 산업계에서 불법자금업체 근절에 많은 관심을 가질 수 있게 하기 위해 금융감독원 비은행감독국 비제도금융조사팀에서 배포한 $\ulcorner$불법자금 모집업체 고수익 보장 유혹에 주의$\lrcorner$ 에 대한 보도자료의 세부내용을 게재한다.