Lightweight Printed Dipole Antenna Array With 3×2 Beamforming Network for Wide UAV Communication Coverage

Dong‑Geun Seo,Jeong‑Soo Park,Gun ‑Ki Lee,Wang‑Sang Lee 대한전기학회 2020 Journal of Electrical Engineering & Technology Vol.15 No.4

In this paper, a lightweight printed dipole antenna array with 3×2 beamforming network for wide unmanned aerial vehicle (UAV) communication coverage is presented. The proposed antenna consists of an upper substrate, a lower substrate, and two supports with a microstrip feeding. The upper substrate has a two-element printed dipole antenna array, and the lower substrate includes a beamforming feeding circuit and a ground plane as a refector of the proposed antenna array for gain improvement. For wide beam coverage, the proposed feeding network consists of three RF switches, one Wilkinson power divider, and one 90° hybrid coupler, and generates the wide beam using one broadside beam and two end-fre beams. Measured impedance bandwidth, peak gain, and half-power beamwidth (HPBW) of the proposed array operated from 5.03 to 5.15 GHz are approximately 2 GHz, 4.3 dBi, and 155°, respectively.

조혈모세포이식 환자에서 발생한 Cytomegalovirus 질환의 특징 : 일개 대학변원에서 최근 10년간의 경험

최수미,이동건,박선희,김시현,김유진,민창기,김희제,이석,최정현,유진홍,김동욱,이종욱,민우성,신완식,김춘추 대한감염학회 2009 감염과 화학요법 Vol.41 No.1

Background : Studies on cytomegalovirus (CMV) diseases in Korean hematopoietic stem cell transplant (HSCT) recipients are lacking and do not reflect the recent trends of advances and changes. Therefore, we tried to analyze the clinical features of CMV diseases in HSCT recipients over the past 10 years at a tertiary university hospital in Korea. Methods : Retrospective review of medical records was done for all adult HSCT patients who received transplant at the Catholic HSCT Center from January 1998 to January 2008. Results : Forty-four cases (2.2%) of CMV diseases were identified. CMV pneumonia was diagnosed in 17 patients, retinitis in 16 patients, enterocolitis in 7 patients, esophagitis 1 patient, gastritis in 1 patient, duodenitis in 1 patient, and hepatitis in 1 patient. The median onset of symptom was 90 days after transplantation. Late CMV diseases accounted for 47.7%. CMV related death varied from 0 to 58.8% according to the involved organ. CMV retinitis was diagnosed relatively later in the course of transplantation mostly in patients who had chronic graft versus host disease (GVHD). On the contrary, CMV enterocolitis mainly occurred in patients who suffered from acute GVHD. The overall concurrent CMV reactivation was documented to be 63.6%: the concurrent CMV reactivation was observed only in 37.5% of patients with retinitis. Conclusions : We observed some differences in the pattern of CMV disease manifestation according to the involved organ and reconfirmed the fact that CMV pneumonia is the most common and fatal disease in HSCT recipients. Additionally, CMV retinitis was not uncommon in HSCT recipients. Since specific marker does not exist in predicting retinitis, regular ocular examination should be done thoroughly, especially in patients with chronic GVHD.

조혈모세포이식 환자에서 침습성 진균 감염에 대한 Micafungin의 예방 효과 및 안전성

김시현,이동건,최수미,권재철,박선희,최정현,유진홍,이성은,조병식,김유진,이석,김희제,민창기,조석구,김동욱,이종욱,민우성,박종원 대한감염학회 2010 감염과 화학요법 Vol.42 No.3

Background: Micafungin, a potent inhibitor of 1,3-β-D-glucan synthase, is a novel antifungal agent of the echinocandin class. In vitro study showed that micafungin was effective against Aspergillus species as well as Candida species, but clinical data on the prophylactic efficacy against invasive fungal infections (IFIs) other than candidiasis are still lacking. Materials and Methods: We identified 60 consecutive adult hematopoietic stem cell transplantation (HSCT) recipients who received at least 3 doses of micafungin during neutropenic period. Micafungin was started as an alternative in patients who were intolerant or had adverse events (AEs) to primary prophylactic antifungal agents. We retrospectively reviewed the medical records and analyzed the efficacy and safety of micafungin for prophylaxis against IFIs. Results: The patients either had autologous (n=9) or allogeneic (n=51: 1 syngeneic, 24 sibling, 26 unrelated donor) HSCT. Itraconazole oral solution (n=58) was the most frequently used first line antifungal agent for prophylaxis and was administered for median 11 days. The most frequent cause of switch to micafungin was vomiting (n=42). The duration of neutropenia and micafungin administration was median 13 and 12 days, respectively. A successful outcome was achieved in 45 (75%) patients. Empirical antifungal therapy was initiated in 13 (22%) patients. There were 2 cases (3.3%) of breakthrough fungal infections which comprised a probable invasive pulmonary aspergillosis and a possible invasive fungal sinusitis. There was no case of invasive candidiasis. A total of 53 (88%) patients experienced at least one AE regardless of causality during micafungin administration. The most frequent AEs were hypokalemia, vomiting, diarrhea, and elevated serum aspartate aminotransferase or alanine aminotransferase. Among the aforementioned AEs, only 1 case of diarrhea could be classified as a probable relation with micafungin when causality was assessed. There was no AEs that caused discontinuation of micafungin. Conclusions: Micafungin seems to be a safe and effective agent for prophylaxis of IFIs including aspergillosis as well as candidiasis in HSCT recipients. However, further large, prospective, and randomized comparative studies are warranted for aspergillosis.

가축에서 분리된 Vancomycin 내성 장구균의 내성유전자 구조 분석을 통한 분자생물학적 역학 연구

허지영,이선민,이석호,이위교,용동은,이경원,신완식,이동건 대한임상미샐물학회 2003 Annals of clinical microbiology Vol.6 No.2

한약에 의해 유발된 급성 간질성 신염 2례

김덕윤,박동건,김응석,강영모,양창헌,이정호,이동철,이영현,김정란 동국대학교 경주대학 1996 東國論集 Vol.15 No.-

간질성 신염은 신장의 간질을 선택적으로 침범하는 염증성 질환으로 여러가지 원인에 의해 유발되며, 이 중 약물에 의한 경우는 각종 항생제, 비스테로이드성 진통제, 항경련제, 이뇨제, 면역억제제등에 의한 증례들이 보고되고 있다. 현재 각종 질환-특히 만성질환-의 치료에서 한약이 차지하는 비중이 적지 않으나, 그 각각의 성분들이 유발할 수 있는 부작용들에 대한 연구는 거의 없는 실정이다. 저자들은 관절염 치료를 위해 중국산 한약을 복용한 후 복통, 피로감 및 육안적 혈뇨를 주소로 내원한 두 환자에서, 단백뇨와 신기능 장애를 보여 시행한 신조직 생검상 급성 간질성 신염에 합당한 병리학적 소견을 보이고, 한약 복용 중지 후 급속한 회복을 보여, 한약에 의해 유발된 것으로 사료되는 급성 간질성 신염 2예를 경험하였기에 문헌고찰과 함께 보고하는 바이다. Acute interstitial nephritis is a disease characterized by renal interstitial inflammatory cell infiltration and acute renal functional deterioration. This is caused mainly by antibiotics, NSAID and diuretics such as thiazide, but cases induced by herb medication are rare. We experienced two cases of acute interstitial nephritis after treatment with herb medication. One 71-year-old female patient and the other 60-year-old female were admitted to the hospital because of general weakness and gross hematuria. Microscopic hematuria, pyuria, and proteinuria were presented. After definitive diagnosis with a renal biopsy, we noted rapid recovery of renal function by drug withdrawal and steroid therapy. We report these cases with a review of the referenced literatures. Key Words : Herb medication, Acute Interstitial nephritis.

동종 조혈모세포이식 후 발생한 크립토콕쿠스 척추염 1예

고윤호,임동준,이성수,조유경,이동건,최정현,김유진,민창기,김동욱,박정미,김춘추,신완식 대한감염학회 2001 감염 Vol.33 No.4

Skeletal cryptococcosis is an uncommon infection. Cryptococcus is a common cause of meningitis and infects 7∼10% of patients with AIDS. As well as AIDS, the infection may be seen in association with leukemia, lymphoma, Hodgkin's disease, sarcoidosis, tuberculosis and diabetes, also in patients on steroid medication. But there is no case report of skeletal cryptococcosis following allogeneic hematopoietic stem cell transplantation. A 40-year-old woman was admitted to the hospital because of low back pain. She had chronic myelogenous leukemia for 2 years and underwent allogeneic hematopoietic stem cell transplantation 8 months ago. She have been treated with steroid and cyclosporine orally because of chronic graft versus host disease. On examination she was afebrile and had posterior lower lumbar tenderness. But, she had no reduced strength of low extremities. Open biopsy was underwent. Histology demonstrated budding, round-to-oval, refractile yeast-like organisms within debris. The results of a lumbar puncture were unremarkable and cerebrospinal fluid culture failed to grow bacteria and yeast. The patient was treated with amphotericin B (1 gram) and AmBisome□ (2.8 gram) over 6 weeks. Three months after cessation of therapy, the patient was doing well.(Korean J Infect Dis 33:298∼301, 2001)

제대군인 취업지원 프로그램 구안

정철영,서우석,김성호,이예성,최동선,이종범,이성식,이건남,양안나,김성남 한국직업능력개발원 2007 직업능력개발연구 Vol.10 No.1

이 연구의 목적은 중·장기복무를 마치고 제대하여 재취업하고자 하는 제대군인들의 원활한 전직을 돕기 위한 제대군인 취업지원 프로그램의 개발방향과 개발안을 제시하는 데 있다. 이를 위해 국내·외에서 이루어지고 있는 제대군인 취업지원 프로그램의 실태를 분석하였고, 제대군인 취업지원 프로그램에 대한제대예정군인 및 제대군인과 기업체의 요구를 분석하여 시사점을 도출하였다. 그리고 이를 기초로 제대군인 취업지원 프로그램의 기본방향과 전체 흐름도, 세부 프로그램 개발안을 제시하였다. 이를 위해서 활용된 연구의 방법은 문헌연구, 조사연구, 전문가협의회 등이다. 이 연구를 통해서 제시된 제대군인 취업지원 프로그램의 개발방향과 개발안을 토대로, 일관되고 지속적인 수요자 중심의 제대군인 취업지원 프로그램의 개발이 가능할 것이다. The purpose of this study is to suggest plans and directions for developing. job-seeking support program for military veterans. The study is conducted through literature review, survey and interview. The results of this study are as follows: ⒧ basic development directions and flowchart of job-seeking support program for military veterans are suggested; and ⑵ development plans for sub-programs are suggested.

비응축성 기체 존재 시 수직관 외벽에서의 응축 열전달계수 상관식 개발

장영준(Yeong-Jun Jang),최동재(Dong-Jae Choi),김신(Sin Kim),정동욱(Dong Wook Jerng),이연건(Yeon-Gun Lee) 대한기계학회 2018 大韓機械學會論文集B Vol.42 No.3

본 연구에서는 비응축성 기체(공기)가 존재할 때, 10 mm의 직경을 갖는 수직 튜브 외벽에서의 응축 열전달계수를 측정하였다. 압력 2~5 bar, 공기 질량분율 10~75 %의 범위에서 실험을 수행하였다. 응축튜브 직경의 차이가 열전달계수에 미치는 영향을 평가하기 위해 측정 결과를 외경 40 mm의 응축튜브로부터 얻은 Lee의 실험 결과와 비교하였다. 본 연구의 측정결과와 Lee, 그리고 Dehbi의 실험결과를 이용하여 전열관의 직경에 의한 영향을 고려할 수 있는 실험적 상관식을 제안하였다. 제안된 상관식의 검증을 위해 Kawakubo의 실험결과와 예측값을 비교하였고, 평균 표준편차는 약 27 %로 나타났다. In this study, condensation heat transfer coefficients are measured in the presence of noncondensable gas (i.e., air) on a vertical tube with a 10-mm outer diameter. Experiments are conducted at pressures ranging from 2 to 5 bar and an air-mass fraction from 10 to 75 %. The experimental results are compared to the heat transfer coefficients obtained on a 40-mm O.D. tube, researched by Lee et al. Using the consolidated data from this study and Lee"s and Dehbi"s tests, a new empirical correlation for the condensation heat transfer coefficient of an air-steam mixture is developed. The proposed correlation is assessed against Kawakubo"s experimental results, and the mean standard deviation is ~27 %.

지역사회획득 폐렴의 치료지침 권고안

송재훈,정기석,강문원,김도진,배현주,서지영,심태선,안중현,안철민,우준희,이남용,이동건,이미숙,이상무,이영선,이혁민,정두련,지역사회획득 폐렴 치료지침 제정위원회 대한감염학회 2009 감염과 화학요법 Vol.41 No.3

A successful therapy of community-acquired pneumonia requires appropriate empirical antimicrobial therapy. Etiology and antimicrobial susceptibility of major pathogens of pneumonia can differ by country. Therefore, an ideal treatment guideline of community-acquired pneumonia should be based on the studies performed in each country. We developed a treatment guideline for community-acquired pneumonia in immunocompetent adults in Korea. This guideline was developed by the joint committee of the Korean Society for Chemotherapy, the Korean Society of Infectious Diseases, and the Korean Academy of Tuberculosis and Respiratory diseases.

국내 호중구감소성 발열 환자에게 경험적 항진균제로 투여한 Amphotericin B deoxycholate와 Itraconazole 주사제의 비용-확인분석 : 예비보고

이동건,송영구,유진홍,최수미,최정현,박선희,신완식 대한감염학회 2004 감염과 화학요법 Vol.36 No.5

목적 : 진균감염이 점차 증가되고 있고 이를 치료하기 위한 비용 역시 증가하고 있지만 국내에서는 비용분석에 대한 연구가 거의 없는 실정이다. 본 연구에서는 호중구감소성 발열 환자에게 경험적 항진균제로 amphotericin B deoxycholate (ABV)혹은 정맥내 itraconazole (ITZA)을 투여할 때의 약물경제학적 측면을 후향적으로 비교해보고자 하였다. 재료 및 방법 : 같은 반응률을 보인다고 가정한 비용-확인분석 모델을 이용하여 가톨릭대학교 조혈모세포이식센터에서 혈액종양으로 항암치료 혹은 조혈모세포이식을 시행한 환자를 대상으로 자료를 수집하였다. 항진균제 투여에 대한 정보는 기존에 출판된 논문 및 학회 심포지움자료를 참고하였고, 논문에서 얻지 못한 정보는 가톨릭대학교 성모병원 의무기록실, 정보지원팀, 진료비관리팀의 협조를 받아 2003년 6월 1일부터 11월 30일까지의 자료를 분석하였다. ITZA에 대한 자료는 2003년 11월 제한적으로 1차 약제로 사용할 수 있게 되었던 때의 자료와 경험을 참조하였다. 결과 : 320명의 환자 중 149명(46.5%)에서 경험적 항진균제를 사용하였고 평균 투여일수는 ABV 17.0일, ITZA 9.8일이었다. 이상반응 발현율은 ABV 54%, ITZA 5%였다. ABV 투여환자 중 11명 (7.4%)에서 혈액투석을 평균 6.5일간 시행하였다. ITZA 투여시 간독성으로 혈장분리반출술, 인공간 등이 필요한 경우는 없었다. 경험적 항진균제를 ABV로 시작한 군(ABV군)은 1인당 1,229,495원, ITZA로 시작한 군(ITZA군)은 1인당 1,434,605원이 소요되어 ITZA군에서 205,110원 (16.7%)이 더 소요되었다. 평균 16일간 항진균제를 사용하여 1일 12,819.4원의 차이가 있었다. 결론 : 비용-확인 분석법에서 ITZA군이 ABV군 비해 하루 12,819.4원의 비용이 더 소요되었다. 비록 ITZA군에서 비용이 더 들었지만 1일 약가차이인 4.7배와 비교하여 많이 감소하여 항진균제의 비용을 1일 약가로 비교하는 것보다는 재원일수, 이상반응 발현율 등을 고려하는 총입원비용으로 약물경제학을 비교하는 것이 더 합당할 것으로 사료된다. 그 외에 환자의 예후, 삶의 질, 사회적 간접비용 등을 고려하는 전체적인 약물경제학을 비교하는 잘 계획된 전향적 연구가 추가로 필요하겠다. Background : The increasing incidence of systemic fungal infections and the rising medical cost have focused the need to determine the economic issues of antifungal agents. Nevertheless there have been only few reports about the cost analysis in Korea. We retrospectively investigated to compare the pharmacoeconomic aspects of amphotericin B deoxycholate (ABV) with those of intravenous itraconazole (ITZA) in the empirical treatment of febrile neutropenic patients. Materials and Methods : Through the cost-identification analysis model, on the presumption that two groups would show identical response, we collected data of patients who received hematopoietic stem cell transplantation (HSCT) or chemotherapy in Catholic HSCT center from Jun 1, 2003 to Nov 30, 2003. The literatures about information on antifungal therapy were extensively reviewed. Other unpublished information was provided by information assistant team, cost management team, and medical record unit in the same hospital. Results : Empirical antifungals were given to 149 out of 320 patients (46.5%). The average duration of administration were 17.0 days for ABV and 9.8 days for ITZA. The rates of adverse events were 54% and 5% for ABV and ITZA, respectively. Eleven (7.4%) patients given ABV received hemodialysis for 6.5 days in average. Among patients given ITZA, none developed hepatotoxicity requiring plasmapheresis or artificial liver. It cost 1,229,495 won/patient for the ABV group (starting ABV as empirical antifungal agent) and 1,434,605 won/patient for the ITZA group (starting ITZA as empirical antifungal agent) which was 16.7% more expensive than ABV group. When we compare the average daily cost for 16 days, the ITZA group spent 12,819.4 won/patient/day more than the ABV group. Conclusion : The cost-identification model in this study revealed that ITZA group cost more than ABV group. However, the difference in expense decreased when 1 day-cost was compared (4.7 times greater than ABV). It would be more reasonable to consider the total cost of anti-fungals during the hospitalization rather than 1 day cost in considering pharmacoeconomics. Well designed prospective study considering prognosis of patients, quality of life, and indirect social cost should be warranted.