배열 안테나를 사용한 디지털 비디오 방송용 OFDM 수신기의 성능평가

전제훈,노현민,변건식 東亞大學校附設 情報技術硏究所 2004 情報技術硏究所論文誌 Vol.12 No.1

Orthogonal frequency division multiplexing(OFDM) is becoming the chosen modulation technique for wire and wireless communications with fast data rate because of good spectral effciency and sufficient robustness of fading channel. Digital Video Broadcating is using OFDM to modulate. But Digital Video Broadcating has performance degradation in moving reception according to DOA(Direction of Arrival). The purpose of this paper is to improve reception performance using array antenna in environment with doppler effect.

The Structural-Dependent Characteristics of Rashba Spin Transports in In_0.5Ga_0.5As/In_0.5Al_0.5As Heterojunctions

Choi, Hyon-Kwang,Hwang, Sook-Hyun,Jeon, Min-Hyon,Yamda, Syoji The Korean Institute of Electrical and Electronic 2011 Transactions on Electrical and Electronic Material Vol.12 No.4

The growth and characterization of $In_{0.5}Ga_{0.5}As/In_{0.5}Al_{0.5}As$ narrow-gap inverted high electron mobility transistor structures, developed as a candidate material for spin-injection devices, are presented in this study. We have grown samples possessing surface $In_{0.5}Ga_{0.5}As$ channels of different thicknesses (30 nm and 60 nm) both with and without a thin 3 nm $In_{0.5}Ga_{0.5}As$ cap layer by using molecular beam epitaxy. We then investigated the in-plane transport properties as well as the Rashba spin-orbit coupling constant of the two-dimensional electron gas confined at the heterojunction interface.

Poster Session : Opti-Sequence Finder: A bioinformatics tool for an antisense technique in wet experimrnts

( Ho Sang Jeon ),( Seong Jo Kim ),( Seung Pyo Hong ),( Hyon Chang Kim ),( Churl K. Min ),( Han Jip Kim ) 생화학분자생물학회 2006 생화학분자생물학회 춘계학술발표논문집 Vol.2006 No.-

당유자 과피 발효물의 플라보노이드 성분 변화 및 항산화 활성

현재석(Jae-Seok Hyon),강성명(Sung-Myung Kang),한상원(Sang-Won Han),강민철(Min-Cheol Kang),오명철(Myung-Cheol Oh),오창경(Chang-Kyung Oh),김동우(Dong-Woo Kim),전유진(You-Jin Jeon),김수현(Soo-Hyun Kim) 한국식품영양과학회 2009 한국식품영양과학회지 Vol.38 No.10

당유자 과피를 식품미생물인 효모를 이용하여 발효 후 80% 에탄올로 추출하여 발효 전과 후의 플라보노이드 함량 및 성분 변화와 항산화 활성의 차이를 비교 분석하였다. LC/MS를 통한 플라보노이드 분석 결과, 발효 후 추출물에서 neohesperidin과 naringin의 함량 변화는 큰 차이가 없었으나, hesperidin과 일부 플라보노이드 성분은 감소하였으며, 특히 3',4',5',5,7-pentamethoxyflavone은 발효 후에 그 함량이 크게 감소하였다. 이에 반하여 친수성 unknown 화합물들이 크게 증가하는 것을 LC/MS을 통하여 확인할 수 있었다. 이는 효모를 통한 발효과정 중에 플라보노이드 성분이 다른 형태로 전환되었으며, 이렇게 전환되어진 성분들을 함유한 FCGP는 CGP보다 DPPH, hydroxyl, alkyl 및 hydrogen peroxide 소거활성 등과 같은 항산화 활성을 크게 증가시켰다. 결론적으로 효모를 이용하여 당유자 과피를 발효시킴으로써 생리활성 성분의 일부를 전환시킴으로써 항산화 활성 등과 같은 기능성을 향상시킬 수 있어, 향후 당유자 과피의 발효에 의한 다양한 건강기능식품으로서의 개발이 가능한 것으로 사료된다. In this study, we investigated the change of antioxidant activity and flavonoid contents by fermentation of Citrus grandis Osbeck peel (CGP) using the Saccharomyces cerevisiae (KCCM35053), comparing to unfermented CGP. Total flavonoid content in the fermented Citrus grandis Osbeck peel (FCGP) was 3,768 g/100 g sample and higher than that of CGP. The antioxidant activities of FCGP was determined by DPPH, hydroxyl, alkyl radicals, and hydrogen peroxide scavenging assays. FCGP showed higher activities than CGP in all scavenging assays. The IC50 values of FCGP were 261.3 ㎍/mL for DPPH; 1,474 ㎍/mL for hydroxyl; 90.9 ㎍/mL for alkyl and 1,195 ㎍/mL for H₂O₂ in respective scavenging assays. Flavonoid compositions of both samples were determined by liquid chromatography/mass spectrometry (LC/MS). In the spectrum FCGP was similar to CGP in the contents of neohesperidin, naringin and an unknown No. 7 compound, but some unknown compounds (No. 1, 2, 4, 5, 6) were higher than CGP in each flavonoid contents. Therefore, the fermentation of CGP could increase the contents of unknown compound and improved antioxidant activities.

만성 비판막성 심방세동의 전기적 심율동전환후 장기 추적관찰 성적

전성희(Seong Hee Jeon),현민수(Min Su Hyon),이상훈(Sang Hoon Lee),조성제(Sung Je Cho),고경환(Kyung Whan Ko),윤재형(Jae Hyung Yoon),이수금(Su Geum Lee),김명아(Myung A Kim),박성훈(Seong Hoon Park) 대한내과학회 1999 대한내과학회지 Vol.56 No.4

Objectives : We performed a prospective observation for the patients with chronic nonvalvular atrial fibrillation who underwent electrical cardioversion after failed pharmacological cardioversion with amiodarone. The aim of this study was to look at the immediate sinus conversion rate, the maintenance rate of sinus rhythm at long-term follow-up, and the clinical and echocardiographic parameters that influence on the rate of immediate sinus conversion and maintenance of sinus rhythm. At simultaneously, we intended to evaluate the efficacy of electrical cardioversion for the patients with chronic nonvalvular atrial fibrillation. Methods : After anticoagulation therapy with coumadine for four weeks before cardioversion, we tried pharmacological cardioversion with amiodarone first. Failed cases included in this study. The direct current cardioversion was performed under transesophageal echocardiography monitoring to exclude the left atrial thrombus and to measure various echocardiographic parameters. After successful sinus cardioversion, we prescribed amiodarone with maintenance doses and coumadine at least 4 weeks. Transthoracic echocardiography was performed before cardioversion and one day, one month, 3 months, 6 months, and 9 months after sinus conversion. The minimum duration of atrial fibrillation was one month before the trial of pharmacological cardioversion. Results : 1) The total number of patients was forty three (male : 28, female : 15, average age : 60±9). The initial success rate of sinus conversion was 88 %. 2) The maintenance rate of sinus rhythm with maintenance dose of amiodarone was 52 % after 9 months follow-up. 3) The direct current cardioversion was performed to 10 patients among 17 patients who recurred atrial fibrillation after sinus conversion. Among 10 patients, 5 patients of them were converted to sinus rhythm and maintained sinus rhythm after 9 months follow-up. 4) The initial success rate of sinus conversion was significantly higher in patients with lone atrial fibrillation compared with those patients with other associated heart disease (100 % vs. 83 %, p < 0.05), but the long-term maintenance rate of sinus rhythm was not influenced by the presence of associated disease. 5) The duration of atrial fibrillation before cardioversion was shorter in patients who were naintained sinus rhythm than that of those who were recurred atrial fibrillation. 6) The initial energy requirement at sinus conversion was lower in the patients who were maintained sinus rhythm than that of those who were recurred atrial fibrillation at 9 months follow-up. Conclusions : Direct current cardioversion was an effective treatment modality for patients with chronic nonvalvular atrial fibrillation after failure of pharmacological cardioversion with amiodarone.

치위생(학)과 학생의 방사선안전관리에 대한 지식, 태도 및 행위

전여령(Yeo Ryeong Jeon),조평곤(Pyong Kon Cho),한은옥(Eun Ok Han),장현철(Hyon Chul Jang),고종경(Jong Kyung Ko),김용민(Yong Min Kim) 대한방사선과학회(구 대한방사선기술학회) 2015 방사선기술과학 Vol.38 No.4

목적: 국내 치위생학을 전공하는 학생들의 방사선 안전행위 수준 확인을 위해 방사선 안전관리 지식, 태도, 행위 수준을 분석하여 교육학적 근거를 도출하고자 하였다. 대상 및 방법: 한국대학교육협의회 대학정보공시센터(대학알리미)에 등록된 전국 83개교 치위생(학)과에 재학중인 3,4학년을 대상으로 하였으며 연구도구는 설문지이다. 설문조사는 대학별 각 20부(총 1,660부)를 방문, 우편, e-mail의 방법으로 배포하여 수거된 응답지 중 신뢰도를 확보하고 있는 총 723부를 SPSS/WIN 15.0를 사용하여 빈도, 백분율, 평균과 표준편차, Pearson's correlation으로 분석하였다. 결과: 방사선 안전관리에 대한 치위생(학)과의 지식, 태도, 행위는 모두 상관관계가 있는 것으로 나타났다. 즉, 방사선 안전관리에 대한 행위수준을 높이기 위해서는 지식, 태도 수준을 높일 수 있는 교육이 적용되어야 한다. 또한 개인의 행위에 가장 상관성이 높은 변수는 물리적 환경에 대한 변수로, 이는 물리적 환경이 갖추어져 있지 않으면 방사선 안전행위 수준을 높이는데 한계가 있음을 의미한다. 따라서 치위생(학)과의 방사선 안전행위 수준을 높이기 위해 물리적 환경을 보완해야 하며 개인의 방사선 안전관리 태도 수준 또한 물리적 환경에 대한 태도 변수와 가장 상관성이 높으므로 방사선 안전관리에 대한 개인의 태도 수준을 높이기 위해 물리적 환경에 대한 변수를 보완해야 한다. 결론: 방사선 안전관리에 대한 태도보다 지식이 상대적으로 낮고, 행위 수준이 가장 낮으므로 안전 행위에 대한 강화된 교육정책이 도입되어야 할 것이며 국내의 경우 치위생(학)과를 졸업한 치위생사들이 치과병원에서 전국민의 구강 방사선 촬영 시 방사선 피폭을 감소시킬 수 있는 주체이므로 현재의 교육 시스템에서 방사선 안전관리 행위 수준을 향상시킬 교육적 개입이 필요하다. Objectives : This study tries to find the educational basis based on the radiation safety knowledge, atti-tudes and behaviors to check the level of radiation safety behavior in domestic students who study dental hygiene. Methods : The students of 3rd and 4th grades in 83 universities which have registered on the Korean University Education Council were involved, and they were given a questionnaire for this study. The ques-tionnaire was provided via visit with 20 copies to each university (total 1660 copies), mail by post and e-mail. Among them, we analyzed only 723 copies that we can trust. The data were analyzed with fre-quency, percentage, mean, standard deviation and Pearson's correlation using the SPSS/WIN 15.0. Results : As a result, there are correlations in the students' knowledge, attitudes and behaviors regarding the radiation safety management. It means that the education which can improve the knowledge and atti-tudes should be applied to increase the action level of the radiation safety. In addition, the physical envi-ronment is the most closely correlated with the individual behavior, so it will be limited to improve the behavioral levels of the radiation safety if the physical environment is not prepared. Therefore, the phys-ical environment should be supported to enhance the level of the radiation safety activity, and to increase the individual attitude level of radiation safety. Conclusions : The knowledge level of the radiation safety management is relatively lower than the atti-tudes level, and the behavior level is the lowest. Therefore, the education policy of the safety behavior must be enhanced. For domestic students, the educational intervention is necessary to improve their be-havioral level of radiation safety management because they will be able to reduce the amount of radiation exposure of their patients in dental care after getting a job.

Molecular beam epitaxy growth and characterizations of ZnSe - based epilayers for blue / green laser diodes

Moon-Deock Kim,Min-Hyon Jeon,Hae-Sung Park,Bong-Jin Kim,Jeong-Keun Ji,Eun-Soon Oh,Sang-Dong Lee,Tae-Il Kim 한국진공학회 1996 한국진공학회 학술발표회초록집 Vol.- No.-

Insect Diversity of Mt. Oseosan

Hong, Eui-Jeong,Jeon, Yong-Lak,Yoon, Ju-Chang,Kim, Jin-Young,Lee, Min-Ho,Kim, Jae-Won,Park, Seong-Joon,Kim, Ki-Gyoung,Kim, Joong-Hyon,Kim, Byung-Jin National Science Museum of Korea 2012 Journal of Korean nature Vol.5 No.3

This study were performed from April in 2010 to August in 2011, through regular surveys insects to obtain the list, to measure and assess Mt. Oseosan ecosystem's natural or artificial change, to provide data for systematic management and preservation of the contents of insects. Total 446 species of 108 families belonging to 11 orders were identified. Therefore, The species composition of insect from Mt. Oseosan by present study and previous literatures was a total of 566 species of 122 families under 11 orders including 7 endermic species, 13 management of exotic species, 9 species of IUCN Red List and 73 designated species: Lepidoptera (215 species, 38%) which was the highest, Coleoptera (159 species, 28.1%), Hemiptera(89 species, 15.7%) and Hymenoptera (35 species, 6.18%). We observed biological indicator species of climate change [Sympetrum pedemontanum elatum (Selys), Dichorragia nesimachus (Boisduval)] as well as risk species [Agelastica coerulea Baly, Lycorma delicatula (White), Lymantria dispar (Linn$\acute{e}$)].

주폐동맥협착과 우관상동맥폐색으로 발현한 타카야수동맥염 1 예 -

전성희(Seong Hee Jeon),김연중(Yeoun Jung Kim),김우규(Woo Gyu Kim),류재춘(Jae Choon Ryu),홍석근(Suk Keun Hong),황홍곤(Hweung Kon Hwang),현민수(Min Su Hyon) 대한내과학회 1998 대한내과학회지 Vol.55 No.5

Takayasu's arteritis is generally recognized as a chronic, idiopathic, inflammatory disease, which affects the aorta and the proximal portions of its major branches. We experienced a patient with Takayasu's arteritis who was presented with main pulmonary artery stenosis and right coronary ostial occlusion without involvement of aorta nor its major branches, She was managed with pulmonary arterioplasty and coronary artery bypass graft. This case emphasize that the disease cannot affect the aorta.

증례 / 대동맥판막 폐쇄부전증을 동반한 골형성부전증 1예

전성희(Seong Hee Jeon),김우규(Woo Gyu Kim),김정경(Jeong Keung Kim),김재성(Jae Seong Kim),류재춘(Jae Choon Ryu),홍석근(Suk Keun Hong),현민수(Min Su Hyon),황흥곤(Hweung Kon Hwang) 대한내과학회 1999 대한내과학회지 Vol.56 No.2

Osteogenesis imperfecta is one of the groups of hereditary disorders of connective tissue which includes the Ehlers-Danlos syndrome, the Marfan syndrome, pseudoxanthoma elasticum, and Hurler syndrome. While cardiovascular involvement is associated with each of these disorders, it is least common in osteogenesis imperfecta and is overshadowed by the bony, ocular, otologic, cutaneous, and dental manifestations that are characteristic of the disorder. In evaluating patients with osteogenesis imperfecta, careful attention should be paid to cardiovascular findings and if valvular lesions are noted, patients should be instructed regarding the need for antibiotic prophylaxis for dental and surgical procedures. We report a case of osteogenesis imperfecta associated with aortic regurgitation.