단위 역률을 갖는 3상 BUCK 다이오드 정류기에서의 새로운 DC 리플-전압 저감 기법

이동윤,최익,송중호,최주엽,김광배,현동석,Lee, Dong-Yun,Choy, Ick,Song, Joong-Ho,Choi, Ju-Yeop,Kim, Kwang-Bae,Hyun, Dong-Seok 전력전자학회 2000 전력전자학회 논문지 Vol.5 No.2

본 논문에서는 3상 강압형 다이오드 정류기에서 출력전압의 저주파 리플 전압을 감소시키기 위한 새로운 제어기법을 제안한다. 제안한 펄스 주파수 변조 기법은 강압형 다이오드 정류기의 출력전압과 넓은 부하 범위에 대한 주 스위치의 영전류 스위칭을 보장하기 위해 적용된다. 본 논문에서 적용된 펄스 주파수 변조 기법은 일반적으로 입력전류의 낮은 고조파의 단위 역률의 장점을 지니고 있다. 또한 출력전압에서 보여진 저주파 리플전압을 감소시키기 위해 효과적으로 사용되어진다. 제안된 제어기법을 자세하게 설명하며 그 타당성을 검증하기 위해 시뮬레인션 및 실험을 통하여 검증한다. A technique to suppress the low frequency ripple voltage of the DC output ${\gamma}$oltage in three-phase buck d diode rectifiers is presented in this paper. The proposed pulse frequency modulation method is employed to r regulate the output voltage of the buck diode rectifiers and guarantee zero-current switching of the switch over the Vvide load range. The pulse frequency control method used in tIns paper shows generally good p performance such as low THD of the input line current and unity power factor. In addition, the pulse f freιluency method can be effectively used to suppress the low frequency voltage ripple appeared in the dc output voltage. The proposed technique illustrates its validity and effectiveness through the respective s simulations and experiments.

도서분류와 도서기호에 관한 소고

이동윤,Lee, Dong-Yun 한국도서관협회 1965 圖協月報 Vol.6 No.6

한국 폐경 여성의 골다공증 위험 인자에 관한 연구

이동윤,구승엽,김석현,최영민,문신용,김정구,Lee, Dong-Yun,Gu, Seung-Yeop,Kim, Seok-Hyeon,Choe, Yeong-Min,Mun, Sin-Yong,Kim, Jeong-Gu 한국건강관리협회 2004 한국건강관리협회지 Vol.2 No.2

Objective : To identify the risk factors for postmenopausal osteoporosis in Korea Materials and methods : Bone mineral density (BMD) at the lumbar spine and femoral neck was measured by dual energy X-ray absorptiometry in 808 apparently normal postmenopausal Korean women. Questions about life style, demographic parameters, medical history and social habits etc. were asked on these women; 2ll women with normal bone mineral density, and 597 women with osteopenia or osteoporosis. Results 'Age of >50 years, low body mass index (BMI; <18.5 kg/m2), long duration of menopause(>10 years), and previous history of fracture were associated with increased prevalence of osteopenia or osteoporosis. Women without the outside activity also showed a higher frequency of low bone mass, Risk for osteopenia or osteoporosis was low in women with high BMI (>23 kg/m2) and women with job. The prevalence of low bone mass appeared to be independent of the following parameters: socioeconomic status, familial history, smoking, drinking, exercise, previous use of oral contraceptive, coffee or milk consumption, and degree of sunlight exposure. Conclusion 'Age, BMI, duration of menopause, previous history of fracture and degree of outside activity are the risk factors for postmenopausal osteoporosis in Korea.

흰물떼새(Charadrius alexandrinus)의 번식 성공에 대한 환경 요인의 영향

이동윤 ( Dong-yun Lee ),이주현 ( Ju-hyun Lee ),성하철 ( Ha-cheol Sung ) 한국환경생태학회 2021 한국환경생태학회 학술대회지 Vol.2021 No.2

The nest fate of plovers have been affected from around environmental factors such as vegetation, sediment grain size and others, because these factors correlate with the camouflage and consistent temperature of nest. The Kentish plover (Charadrius alexandrinus) is known to select nest site where vegetation cover is low to easily detect predators. However, recent studies show that their nest successes positively correlate with vegetation cover rate, because vegetation can hide incubating parents from predators. Therefore, in this study, we investigated the relationships between vegetation cover and nest fate, and between breeding success and other environmental factors (such as, sand, shell etc.). This study was carried out from early March to late July in 2020 at Saemangeum, specifically (1) Mangyeong estuary, Gunsan, Jellabuk-do; (2) Dongjin estuary, Buan, Jellabuk-do. The study area is reclaimed land with sandy coastal environment, and the size of Mangyeong estuary was about 1,011 ha, Dongjin estuary was about 893 ha. Sedges (family Cyperaceae) were the major vegetation in these locations. We analyzed the effect of environmental factors on the breeding success of Kentish plovers. First, we measured five variables in field: nest diameter (cm), nest height (cm), nest slope (°), distance from nest to the nearest vegetation (m), and the height of the nearest vegetation (cm). Then, we obtained the coordinate of each nest with a GPS and measured distance from nest to water resource (m) using satellite map (Kakao map). We also estimated the cover of environmental factors using 1m² quadrat. The quadrat photos were taken by two ways for each nest: 1) centered on the nest within a 1m²; 2) randomly selected two points in 10m distance from a nest. On the analysis of variables in quadrat photo, we measured the 11 variables. First, we measured the cover of nest area (mm²) and the cover of five environmental factors (dry vegetation, vegetation, sand (grain size < 2 mm), shell and other object; mm²) on the quadrat photos of centered on the nest within a 1m². Second, we also measured the cover of five environmental factors in each photo and calculated the average of two photos on the each factor on the quadrat photos of randomly selected two points in 10m distance from a nest. For statistical analysis, we translated variables using “X = log10 (x + 1); X = translated value; x = origin value” before modelling and analyzed using Generalized Linear Model (GLM). The model criteria was Akaike Criteria Information (AIC). Then, we used Mann-Whitney U test to compared variables between successful and failed nests in the best model. All statistical analysis had a significant effect at p < 0.05. We analyzed 285 quadrat photos (95 photos within a 1m² quadrat centered on each nest; 190 photos on the randomly selected points within 10m area from each nest) from 95 nests: 60 nests in Mangyeong (35 successful nests and 25 failed nests); 35 nests in Dongjin (28 successful nests and 7 failed nests). As the results of GLM, the best model was composed not environmental factors, but three nest factors: nest area, nest diameter and nest slope. In this model, nest area and nest diameter were significant (p < 0.05). However, according to Mann-Whitney test, these factors did not differ between successful and failed nests (p > 0.05). Therefore, when researchers studied the effect of nest factors on the breeding success, nest area and nest diameter should be considered together. On the effect of environmental factors, all factors, which included vegetation and dry vegetation cover, did not affect breeding success. Thus, the other environmental factors should be studied to reveal which one affects the breeding success of Kentish plovers.

世界史敎育의 當面課題

李東潤(Dong-Yun Lee) 歷史敎育硏究會 1957 역사교육 Vol.2 No.-

한국 폐경 여성에서 경구 에스트로겐 종류에 따른 유방 치밀도에 대한 Medroxyprogesterone Acetate의 효과

이동윤 ( Dong Yun Lee ),최현진 ( Hyun Jin Choi ),최두석 ( Doo Seok Choi ),민용기 ( Yong Ki Min ),최연현 ( Yeon Hyeon Choe ),윤병구 ( Byung Koo Yoon ) 대한폐경학회 2010 대한폐경학회지 Vol.16 No.2

연구목적: 한국 폐경 여성에서 경구 에스트로겐 종류에 따른 medroxyprogesterone acetate (MPA)의 유방 치밀도에 대한 영향을 조사하였다. 연구재료 및 방법: Conjugated equine estrogen (CEE)+MPA 치료 (n=10) 및 estropipate+MPA 치료 (n=16)를 1년간 시행하여, 치료 전후의 X-선 유방촬영술상 유방 치밀도의 변화를 breast imaging reporting and data system (BI-RADS) 판독 및 J-image 프로그램을 이용하여 비치료 대조군 (n=27)과 함께 비교하였다. 결 과: 각 군간 기초 임상 특성의 차이는 없었다. 1년의 호르몬 치료 후, 대조군 (0%)에 비해 CEE+MPA (7/10, 70%; P<0.001) 및 estropipate+MPA (3/16, 18.8%; P=0.002) 치료군에서 유의한 유방 치밀도 증가가 관찰되었으며, CEE를 병합한 경우가 estropipate 병합군에 비해 높은 유방 치밀도 증가를 보였다 (P=0.033). NIH J image로 계산한 치밀 면적의 비율 변화는 대조군에서 0.66%, CEE+MPA 군에서 7.67%, estropipate+MPA군에서 1.48%로 차이를 보이는 경향이 있었다. 결론: 한국 여성에서 estropipate+MPA 치료는 CEE+MPA에 비해 유방 치밀도에 대한 자극 효과가 적으며, 유방 치밀도의 변화는 경구 에스트로겐의 성분에 따라 다를 수 있다. 향후 유방암 위험에 대한 추가 연구가 시행되어야 한다. Objectives: We determined if the impact of medroxyprogesterone acetate (MPA) co-administered with conjugated equine estrogen (CEE) or estropipate differed on mammographic density (MMGD) in Korean postmenopausal women. Methods: In this retrospective study, 53 healthy postmenopausal women without prior hormone therapy (HT) use were included. Smokers, habitual drinkers, women with a body mass index ≥27 kg/㎡, and women with a history of mammoplasty or breast cancer were excluded. HT using MPA (n=26) consisted of the following two groups: CEE (n=10) and estropipate (n=16). Twenty-seven untreated women served as the control group. Mammography was obtained at baseline and 1 year later, and MMGD was assessed based on the breast imaging reporting and data system (BI-RADS) by one radiologist who was blinded to treatment. In addition, the change in the proportion of the dense area after HT was assessed using the J-image program. Data were analyzed with analysis of variance and chi-square or Fisher`s exact test. Results: There were no significant differences in baseline clinical characteristics and MMGD among the three groups. After 1 year of HT, CEE (7/10 [70%]; P<0.001) and estropipate (3/16 [18.8%]; P=0.002) regimens significantly elevated the BI-RADS grade compared with controls (0%), and CEE induced a greater increase in MMGD than estropipate (P=0.033). In addition, the proportion of dense areas assessed using the J-image program increased more with the CEE regimen (7.67%) than the estropipate regimen (1.48%), but there was no statistically significant difference. Conclusion: Estropipate+MPA had a less stimulating effect on MMGD than CEE+MPA in Korean postmenopausal women. The change in MMGD induced with MPA might depend on the oral estrogen preparation. A further study on breast cancer risk based on combination HT is warranted.

DAMP-modulating Nanoparticle for Successful Pancreatic Islet and Stem Cell Transplantation

Dong Yun Lee(이동윤) 한국고분자학회 2022 한국고분자학회 학술대회 연구논문 초록집 Vol.47 No.2

Biodegradable Composite Materials Using PLA and PBAT

Dong Yun Lee(이동윤) 한국고분자학회 2024 한국고분자학회 학술대회 연구논문 초록집 Vol.49 No.1

한국 폐경 여성에서 호르몬 대체요법시 치료 제제에 따른 유방 치밀도의 변화

이동윤 ( Dong Yun Lee ),김상돈 ( Sang Don Kim ),최영식 ( Young Sik Choi ),지병철 ( Byung Chul Jee ),구승엽 ( Seung Yup Ku ),서창석 ( Chang Suk Suh ),최영민 ( Young Min Choi ),김정구 ( Jung Gu Kim ),문신용 ( Shin Yong Moon ),김석현 대한폐경학회 2003 대한폐경학회지 Vol.9 No.3

목적 : 본 연구는 한국 폐경 여성에서 호르몬 대체요법과 연관된 유방 치밀도의 변화를 평가하기 위하여 시행되었다. 연구 대상 및 방법 : 본 연구에서는 호르몬 대체요법을 시행 받은 폐경 여성 294명을 대상으로 치료 제제에 따라 매일 tibolone 2.5 mg을 투여 받은 군(n=119), conjugated equine estrogen(CEE) 0.625 mg/medroxyprogesterone(MPA) 2.5 mg으로 지속적 병합요법을 시행 받은 군(n=93), CEE 0.625 mg으로 단독요법을 시행 받은 군(n=40) 및 raloxifene 30 mg을 투여 받은 군(n=42)으로 대변하였으며, 호르몬 대체요법을 시행 받지 않은 폐경 여성 36명을 대조군으로 설정하였다. 대상 여성에서 유방촬영술(mammography)을 호르몬 치료 시작 전과 치료 1년 후에 각각 시행한 후 유방 치밀도(breast density)의 변화를 후향적으로 각 군에서 비교 관찰하였다. 결과 : 대상 여성의 연령, 분만력, 폐경 연령, 폐경 후 기간, 체중, 신장 및 체질량지수(BMI)는 각 군간에 통계학적으로 유의한 차이가 없었다. 호르몬 대체요법 1년 후 유방촬영술에서 관찰된 유방 치밀도의 증가는 지속적 병합요법군에서 25.8%(24/93)로서 tibolonerns의 11.8%(14/119), raloxifene군의 2.4%(1/42)에 비하여 각각 유의하게 높았다(p<0.05). 결론 : 본 연구 결과 호르몬 대체요법을 시행 받은 폐경 여성에서 관찰된 유방 치밀도의 변화는 치료 제제에 따라 상이하다는 것을 확인하였으며, 특히 progestogen을 이용한 지속적 병합요법이 유방 치밀도 변화에 중요한 영향을 미치는 것으로 사료된다. Objective : This study was performed to evaluate the mammographic changes in breast density that were associated with hormone replacement therapy(HRT) in Korean postmenopausal women. Materials and Methods : In this retrospective study, 294 postmenopausal women were classified as the four groups according to the regimen of HRT; a daily treatment of tibolone 2.5 mg(n=119), conjugated equine estrogen(CEE) 0.625 mg/medroxyprogeserone(MPA) 2.5 mg(n=93), CEE 0.625 mg only(n=40) or raloxifene 60 mg(n=42), and they were compared with the control group of postmenopausal non-HRT users(n=36). Mammography was performed at baseline and after 1 year of treatment, and the incidence of changes in mammographic density was evaluated and compared among the groups. Results: There were no significant differences in age, parity, age at menopause, years after menopause, weight, height, and body mass index(BMI) among the groups. The risk of an increase in mammographic density after 1 year of treatment was significantly higher in CEE/MPA group(24/93, 25.8%), compared with tibolone(14/119, 11.8%) and raloxifene(1/42, 2.4%) group(p<0.05). Conclusion : This study showed that the changes in mammographic breast density related to postmenopausal HRT were dependent on the regimen of HRT. The continuous administration of progestogen as a component of the combined HRT seems to affect the breast density significantly.

Hemoglobin-DNA/pyterpy 박막을 이용한 과산화수소의 전기화학적 검출

이동윤(Dong-Yun Lee),최원석(Won-Suk Choi),박상현(Sang-Hyun Park),권영수(Young-Soo Kwon) 대한전기학회 2008 대한전기학회 학술대회 논문집 Vol.2008 No.7