신규 제초제 후보물질 M-862의 광엽잡초에 대한 제초활성

구대원(Dae-Won Koo),조남규(Nam-Gyu Cho),황기환(Ki-Hwan Hwang),구석진(Suk-Jin Koo),박기웅(Kee Woong Park) 한국잡초학회 2019 한국잡초학회 별책(학술대회 초록집) Vol.39 No.2

고전압 GaN 쇼트키 장벽 다이오드의 완충층 누설전류 분석

황대원(Dae Won Hwang),하민우(Min-Woo Ha),노정현(Cheong Hyun Roh),박정호(Jung Ho Park),한철구(Cheol-Koo Hahn) 大韓電子工學會 2011 電子工學會論文誌-SD (Semiconductor and devices) Vol.48 No.2

본 논문에서 실리콘 기판 위에 성장된 GaN 에피탁시를 활용하여 고전압 쇼트키 장벽 다이오드를 제작하였으며, 금속-반도체 접합의 열처리 조건에 따른 GaN 완충층 (buffer layer) 누설전류와 제작된 다이오드의 전기적 특성 변화를 연구하였다. Ti/Al/Mo/Au 오믹 접합과 Ni/Au 쇼트키 접합이 제작된 소자에 설계 및 제작되었다. 메사를 관통하는 GaN 완충층의 누설전류를 측정하기 위하여 테스트 구조가 제안되었으며 제작하였다. 700℃에서 열처리한 경우 100 V 전압에서 측정된 완충층의 누설전류는 87 ㎁이며, 이는 800℃에서 열처리한 경우의 완충층의 누설전류인 780 ㎁보다 적었다. GaN 쇼트키 장벽 다이오드의 누설전류 메커니즘을 분석하기 위해서 Auger 전자 분광학 (Auger electron spectroscopy) 측정을 통해 GaN 내부로 확산되는 Au, Ti, Mo, O 성분들이 완충층 누설전류 증가에 기여함을 확인했다. 금속-반도체 접합의 열처리를 통해 GaN 쇼트키 장벽 다이오드의 누설전류를 성공적으로 감소시켰으며 높은 항복전압을 구현하였다. We have fabricated GaN Schottky barrier diode (SBD) for high-voltage applications on Si substrate. The leakage current and the electrical characteristics of GaN SBD are investigated by annealing metal-semiconductor junctions. Ohmic junctions of Ti/Al/Mo/Au and Schottky junctions of Ni/Au are used in the fabrication. A test structure is proposed to measured buffer leakage current through a mesa structure. When annealing temperature is increased from 700℃ to 800℃, measured buffer leakage current is also increased from 87 ㎁ to 780 ㎁ at the width of 100 ㎛. The diffusion of Au, Ti, Mo, O into GaN buffer layer increases the leakage current and that is verified by Auger electron spectroscopy. Experimental results show that the low leakage current and the high breakdown voltage of GaN SBD are achieved by annealing metal-semiconductor junctions.

아토피 피부염 환자에서 집먼지 진드기에 대한 제1형 알레르기 반응과 호흡기 아토피의 가계적 배경에 관한 연구

신자경 ( Ja Kyoung Shin ),구대원 ( Dae Won Koo ),이종주 ( Chong Ju Lee ),장완섭 ( Yean Sub Jang ) 대한피부과학회 1995 대한피부과학회지 Vol.33 No.6

Background : Recent studies have suggested that house dust mite allergy is an important cause of the atopic dermatitis(A.D). However, it is not clear that. what factors may be related to the development of the mite illergy in patients with AD. Objective : This study was done to see whether the presence of a familial background of RA implies a relationship to the mite allergy in AD. Methods : Skin prick test and fluoroallergosorbent, test (FAST) with house dust mit,e were performed in 47 patients wih AD. Results : 1. In comparison the esult of prick test with that of FAST to house dust mite antigen, it showed a concordance ra!e of 82%. And the prick test was more sensitive than the FAST. 2. The prevalence of positive FAST reactions was significantly increased in the patients with AD who had a family hitory of RA than those in patients with AD who had neither family or personal history of RA. 3. The level of specific IgE against house dust mite did not relate to the presence of family cr personal history of RA. 4. The prevalence of positive prick test results did not relate to the presence of family or personal history of RA. 5. The prevalence of positive FAST reactions, the level of specific IgE, and the rate of positive prick test results did not relate to the severity of skin involvement. 6. The most common allergens which caused positive skin reactions were house dust, cat fur, Dermatophagoides farinac, Dermatophagoides pteronyssinus, et al. Antigen score of prick test to 55 common antigens wa. significant increased in the patients with AD who had a family history of RA, but did not relat to the severity of skin involvement or the presence of personal history of RA. Conclusion : We may conclude that type I allergy to the house dust mit,e is not directly related to AD perse. This type of allergy to the mite seems to occur predominantly in those patient s with AD who have a farilial background of RA. (Kor J Dermatol 1995;33(6): 1046-1052)

발주자 손실기반 지체상금 산정 개선방안

장봉조,심재영,구정산,정대원,구교진,현창택,Jang, Bong-Jo,Shim, Jae-Young,Koo, Jeong-San,Jung, Dae-Won,Koo, Kyo-Jin,Hyun, Chang-Taek 한국건설관리학회 2007 건설관리 : 한국건설관리학회 학회지 Vol.8 No.1

공기지연은 건설공사에 있어서 가장 빈번하게 발생하는 클레임의 발생요인이다. 공기지연으로 인한 지체상금은 판결과정에 있어서 많은 분쟁을 불러일으키고 있다. 지체상금은 '손해배상의 예정'으로 실제 발주자가 입은 손실에 대한 보상액이 되어야 한다. 그러나 실제로는 계약 불이행에 대한 위약금의 형태로 적용되고 있다. 이러한 지체상금은 발주자의 실제 손실과 차이가 있으며, 수급자에게 과도한 부담으로 작용한다. 본 연구에서는 발주자의 실제 손실에 기반을 둔 지체상금 산정방법을 제안하고자 한다. The delay of construction is one of the most frequent and complicated elements of the claim. And the liquidated damages cause many disputes during the judgement. The liquidated damages should be a compensation for owner's substantial loss, but actually be applied as a damage for breach of contract. These damages are different from owner's loss and give constructors a excessive burden. So we need a more reasonable system than a lump application system. In this study, we make a Improvement System, that based on owner's substantial loss, and suggest the new liquidated damages calculation method.

아토피피부염 환자에서 자가혈청 피부반응검사 결과에 따른 임상 및 검사소견 분석: 혈청 총 면역글로불린E, 다중 알레르기항원 검사, 임상적 중증도 및 유병기간과의 연관성

김동하 ( Dong Ha Kim ),구대원 ( Dae Won Koo ),이중선 ( Joong Sun Lee ),정경은 ( Kyung Eun Jung ) 대한피부과학회 2016 대한피부과학회지 Vol.54 No.8

Background: The autologous serum skin test (ASST) is a simple test for detecting functional circulating autoantibodies. In addition, immunoglobulin E (IgE) autoreactivity seems to play a role in the pathogenesis and disease course of atopic dermatitis (AD). Objective: The aim of this study was to examine whether the ASST results were positive in AD patients and to find the relationship between ASST and total serum IgE levels, disease severity, disease duration, and multiple allergen simultaneous test (MAST) results in AD. Methods: Fifty-two patients with AD who underwent ASST were included in this study. We analyzed total serum IgE concentrations, severity, duration of disease, and allergen frequencies between the ASST positive and -negative groups. Disease severity was evaluated using the Rajka and Langeland eczema severity score. Results: ASST results were positive in 34.0% (17/52) of patients, and the positivity rates of ASST in IgE-mediated AD patients was 39.0% (16/41), which was significantly higher than in non-IgE-mediated AD patients. Additionally, IgE-mediated AD patients with positive ASST results showed greater disease severity, longer disease duration, and a greater number of allergens than ASST-negative patients (p<0.05). Conclusion: This is the first study to evaluate the results of ASST in patients with AD. According to our results, ASST would be a useful test in AD and could be related to autoimmunity, severity, and disease course of AD, especially in IgE-mediated AD. Further studies with more patients are needed to confirm these findings. (Korean J Dermatol 2016;54(8):601∼607)

기저 세포암에 대한 5 - Fluorouracil 병변내 주입의 치료 효과

이윤정(Yun Jeong Lee),구대원(Dae Won Koo) 대한피부과학회 1994 대한피부과학회지 Vol.32 No.2

Basal cell carcinomas(BCCs) are usually treated with ablative proccdures, but a nonsurgical treatment would conserve tissue and obtain a better cosmetic out come as well as treat patients who refuse surgery or those who are not good surgical candidates. Because of inadequate drug penetration, low cure rates, high recurence rates, and adverse reactions, such as contact dermatitis, topical 5-fluorouracil(5-FU) is unsaitble to treat nodular BCCs. But, int,ralesional 5-FU has been reported to be effective for nodular BCCs. The efficacy and safety of intralesional injection of 5-FU have been evaluated for treatment of BCCs. The results revealed that intralesional injection of 5-FU seems to be effective in the treatment of various premalignant and malignant skin lesions as well as BCCs without side effects. (Kor J Dermatol 1994; 32(2): 337-341)

국내 암석의 암종별 열물성 특성 분석

차장환(Cha, Jang-Hwan),명대원(Myoung, Dae-Won),구민호(Koo, Min-Ho),송윤호(Song, Yoon-Ho),김형찬(Kim, Hyeng-Chan) 한국신재생에너지학회 2007 한국신재생에너지학회 학술대회논문집 Vol.2007 No.11

본 연구에서는 국내 암석을 암종별로 총 292개 채취하였으며 열물성 측정 장비를 이용하여 이들 암석의 열물성을 측정하였다. 이와 더불어 암석의 물리적 특성을 측정하였으며 일부 시료의 경우 XRD 정량분석을 실시하였다. 이들 결과를 이용하여 암석의 열물성 특성과 열물성에 영향을 주는 인자를 파악하였다. 암석의 열물성 측정 결과 열전도도와 열확산계수는 화강암에서 가장 낮은 값을 보였으며 퇴적암, 변성암 순으로 나타났다. 또한 암종별 열물성 값의 범위를 살펴보면 변성암과 퇴적암에서 넓게 분포한다. 암석의 물성과 열물성과의 상관성 분석 결과 공극률이 증가함에 따라 열전도도와 열확산계수가 감소하나 상관성은 미약한 것으로 나타났다. XRD 분석 결과 암석의 열전도도는 석영(SiO₂)의 함량에 따른 선형의 비례관계를 보였다. 이로써 암석의 열전도도는 암석을 이루는 광물의 종류에 의하여 영향을 받음을 알 수 있다. 차후 암석의 구성 광물입자의 배열 상태에 따른 열물성 특성과 퇴적암 및 변성암 시료에 대한 이방성 실험을 통해 편리, 층리 및 엽리 등에 따른 열물생의 이방성 정도를 분석할 예정이다.

만성 자발성 두드러기 환자에서 Omalizumab 치료 반응에 대한 예측 인자 분석

이현이 ( Hyun Yi Lee ),구대원 ( Dae Won Koo ),이중선 ( Joong Sun Lee ) 대한피부과학회 2021 大韓皮膚科學會誌 Vol.59 No.9

Background: The European Academy of Allergy and Clinical Immunology guideline for the management of urticaria published in 2018 recommends adding omalizumab as a third-line therapy. However, data on the potential predictive factors of a successful response to omalizumab are limited in Korea. Therefore, this study aimed to perform a retrospective clinical analysis of the effects of omalizumab in a Korean population of patients affected by chronic spontaneous urticaria (CSU). Objective: To investigate factors affecting the effect of omalizumab treatment and identify factors related to its clinical response. Methods: We retrospectively reviewed the clinical records of patients with CSU treated with omalizumab at the single-center dermatology department from February 2018 to August 2020. Omalizumab was administered at a single dose of 150 mg every 4 weeks. Clinical treatment response was assessed using the urticaria activity score summed over 7 days (UAS7) after the fourth, sixth, and 12th omalizumab injections. Results: Twenty-six patients were enrolled in this study. The mean UAS7 at baseline was 16.9 (range, 4∼28). Treatment was completed in seven patients (26.9%). Three patients (11.5%) discontinued treatment because of poor treatment response. Symptoms improved in all patients at the fourth injection (UAS7=3.9, range 0∼10). The second administration of omalizumab showed that the lower the body mass index (BMI), the better the response to treatment (p<0.05), and a similar trend after an additional injection. Conclusion: The symptoms improved after omalizumab treatment in most patients. Those with a lower BMI and higher total immunoglobulin E levels during long-term treatment showed significantly better treatment responses. (Korean J Dermatol 2021;59(9):685∼692)

영아 급성 출혈성 부종

이윤정(Yun Jeong Lee),구대원(Dae Won Koo),박천욱(Chun Wook Park),이철헌(Cheol Heon Lee) 대한피부과학회 1994 대한피부과학회지 Vol.32 No.2

Infantile acute hemorrhagic edema is a benign disease followed by a spontaneous eomplete recovery without sequelae, characterized by cockade purpura and inflamrntory edema on the face and extremities without any internal origin involvement in 4-month to 2-year-old infants. We report a case of infaniile acute hemorrhagic edema which occared in a 2-year-old female after an upper respiratory illness and compare the clinical and histologic features of this disorder with Henoch-Schonlein purpura. (Kor J Dermatol 1994; 32(2): 332-336)

부분적으로 다른 물성치를 갖는 단순보의 진동해석

배승훈(Seung-Hoon Bae),조대원(Dae-Won Cho),김대환(Dae-Hwan Kim),구정모(Koo Jung Mo),정의봉(Weui Bong Jeong),조진래(Jin Rae Cho) 한국소음진동공학회 2017 한국소음진동공학회 학술대회논문집 Vol.2017 No.4