당뇨병환자에서 아스피린 및 항혈소판제 치료의 최신지견

배학연 朝鮮大學校 附設 醫學硏究所 2004 The Medical Journal of Chosun University Vol.29 No.1

영상 감시 시스템에서의 개선된 Tearing 현상 방지 디스플레이 시스템

이동학,정연권,정선태 崇實大學校 生産技術硏究所 2001 論文集 Vol.31 No.-

In display systems employing an analog monitor, the tearing artifact such that an window screen is divided into two parts showing different scenes can occur when the change of scenes in the moving pictures is very fast, but the frame buffer's refresh rate does not match the monitor's scanning frequency. In the DVR system, a recently popularized visual monitoring system, the tearing artifacts becomes more serious since the frame buffer's refresh rate is vey high due to the requirement of multi-channel display. In this paper, we propose an improved display system for windows-based DVR systems which prevents the tearing artifacts without daterioration of display speed perfromance. The efficiency of the proposed display system is verfied through experiments.

디아조반응을 통한 Pyroglutamic Acid의 용이한 합성

김소연,이학준 한양대학교 이학기술연구소 2000 이학기술연구지 Vol.2 No.

Pyroglutamic acid의 한 단계 합성이 glutamine으로부터 디아조화 반응을 통하여 80% 수율로 성취되었다. 이 반응의 mechanism은 디아조늄 이온의 중간체에 carboxy기의 anchimeric 도움으로 불안정한 α-lactone이 얻어져서 진행될 것이라고 생각된다. 이 반응 방법은 asparagine으로부터 B-lactam 그리고 aspartic acid로부터 B-lactone의 합성에 적용될 수 있다는 것을 제시한다. One step synthesis of pyroglutamic acid was achieved from glutamine by diazotization in 80% yield. The mechanism of this reaction presumably involves anchimeric assistance of the carboxy group in decomposition of an intermediate diazonium ion, leading to a labile α-lactone. This manipulation implies that it can be applied for the synthesis of B-lactone from asparagine and B-lactone from aspartic acid.

Chiral 2-allyl-1,3,2-dioxaborolane-4-5 dicarboxylic acid-diisopropulester-lithium azide 착물의 아지도기 전달반응

이학준,김진연 한양대학교 이학기술연구소 2004 이학기술연구지 Vol.7 No.

키랄성 아지도 유기붕소 화합물 3및 4를 D-및 L-타르타르산으로부터 합성한 후 에폭시화물의 고리열림 반응과 a,B-불포화 카르보닐 화합물에 컨쥬케이트 첨가반응을 시도하였다. 그결과, 도파로의 전파손실이 효율적인 광변조기의 제작에 해가 됨을 볼 수 있었다. Chiral azido organoboron compounds 3 and 4 were synthesized from D and L-tartrate. The ring opening reaction of epoxides and the conjugated addition reaction of a,B-unsaturated carbonyl compounds with compounds 3 and 4 were tried.

325 MHz 이동통신용 집중소자 Y형 서큘레이터의 설계

고연수,성원모,최학근 단국대학교 신소재기술연구소 1997 신소재 Vol.7 No.-

본 논문에서는 325 MHz 이동통신 기지국에 사용되는 집중소자 Y형 서큘레이터를 해석하고, 기존의 복잡한 수식을 통하여 설계하는 방법 대신 도표를 사용해 설계하는 간단한 설계방법을 제시하였다. 그리고, 실제 설계 제작하여 측정결과와 해석결과를 서로 비교 분석하였다. 설계방법은 % 대역폭과 페라이트 사이의 스트립선로의 고유인덕턴스 그리고 페라이트의 포화자화량과의 관계로부터 내부자계의 세기를 결정한 후 이로부터 입력 어드미턴스를 구해 외부의 정합회로를 결정하는 설계방법으로 전개하였다. 해석은 페라이트의 텐서투자율의 성분 μ와 k가 복소함수가 아니라고 가정하고(무손실이라고 하고), 정합회로까지 모두 고려한 등가회로에서 제 3포트를 격리포트로 하여 고유치 해석방법을 적용하여 손실 및 임피던스 그리고 산란행렬 고유치의 위상을 구하였다. 그리고, 이러한 해석방법으로부터 중심주파수 325 MHz에서 %대역폭, 포화자화량, 스트립선로의 고유인덕턴스와 내부자계의 관계를 밝혀서 도표로 제시함으로써 서큘레이터의 설계에 이용할 수 있게 하였다. 실제 제작된 서큘레이터는 중심주파수 325 MHz에서 반사손실이 -31dB, 아이솔레이션이 -32dB, 삽입손실이 -0.219dB로 나타내며, 해석을 통하여 얻은 결과와 거의 유사함을 알 수 있었다. In this paper, a new design method of Iumped-element Y circulator for 325 MHz mobile communication is proposed and the analysis results compared with the measured results. To develop the new design method, internal magnetic field intensity is derived from &bandwidth, characteristic inductance of stripline between two ferrites and saturation magnetization of ferrite to get the input admittance of circulator to obtain the external matching network. The analysis of circulator was based on the assuming that the circulator was lossless and the third port of its equivalent circuit was isolated, and the impedance and phase of scattering coefficient was calculated through the eigenvalues analysis. From this analysis, the relation among %bandwidth, saturation magnetization, characteristic inductance of stripline and internal magnetic field was found and the diagram for the design was suggested. Experimental results of fabricated circulator represent -31dB return loss. -32dB isolation and -0.219dB insertion loss at the center frequency 325MHz and support the theoretical prediction.

(4S,5S)-2-allyl-1,3,2-dioxaborolane-4,5-dicarboxylic acid-diisopropylester-lithium azide 착물의 아지도화 반응

이학준,김진연 한양대학교 이학기술연구소 2002 이학기술연구지 Vol.5 No.-

D-타르타르산 에스테르로부터 키랄 아지도 유기붕소 화합물 3을 합성한 후, 에폭시화물의 고링열림반응을 통하여 아지도 알코올과α,β-불포화 카르보닐 화합물에 1,4-첨가반응을 통하여 β-아지도케톤을 높은 수율로 합성하였다. After the synthesis of a chiral azido organoboron compound 3 from D-tartrate, the afido alcohols and β-azidoketones have been synthesized in excellent yields through the epoxide ring opening reaction and 1,4-addition reaction of α,β-unsaturated carbonyl compounds with compound 3, respectively.

리눅스 기반의 IPv6 이동 네트워크 구현

김종현,이주연,이학용,정충교 강원대학교 정보통신연구소 2007 정보통신논문지 Vol.11 No.-

Mobile networks support the mobility of subnets as well as the mobility of subnets. Node mobility means that the internet connection is sustained while nodes move around. All internet connections are sustained while nodes connected on a subnet move around under the network mobility. We have implemented a mobile network system: MR (mobile Router) and HA (Home Agent) in the linux environment, confirming to the network mobility basic protocol IETF RFC3963. In this paper, we report the implementation experiences. Implementation details and some experimental results are summarized in this paper. With our implementation one can use internet service any time, and anywhere i.e., car, train, airplane, ship, etc.

난황낭종 환자에서 보존적 수술 및 항암 화학요법 후 성공적인 자연임신

정은환, 홍승화, 박연진, 지일운, 김학순 충북대학교 의과대학 충북대학교 의학연구소 2012 忠北醫大學術誌 Vol.22 No.1

침윤성 난소암의 경우 생식력의 보존이 중요한 도전이라고 할 수 있다. 20대 중반의 여성에서 거대 한 난황낭종이 발견되어 생식력의 보존을 위해 보존적 수술과 복합항암화학요법을 시행한 후 임신 및 출산에 성공한 증례를 경험하였기에 문헌고찰과 함께 보고한다.

종격동 종괴를 의심케한 우대동맥궁 1례

김만우,백학연,정춘해,장경식,홍순표,조건국,김종진 朝鮮大學校 附設 醫學硏究所 1987 The Medical Journal of Chosun University Vol.12 No.1

Developmental anomalies of the aortic arch, commonly known as vascular rings, are relatively rare congenital vascular anomalies which can compress the trachea and esophagus. One routine chest film of a patient who was checked and hepatoma-diagnosed in Internal Medicine, Chosun University Hospital left the room for doubt of mediastinal mass. But no subjective symptoms for the mass was told by the patient. This is to report our experience of a patient having right side aortic arch with aberrant left subclavian artery, as proved by diagnosis, but none of congenital heart disease. This right side aortic arch with aberrant left subclavian artery is the most frequent type among right aortic arch, the anomaly of which is usually detected from the incidental suspicion for mediastinal mass at routine chest film; because no symptoms are accompanied therewith.

인슐린 비의존형 당뇨병 환자에서 만성합병증과 혈청 sialic acid농도

김태종,배학연 朝鮮大學校 附設 醫學硏究所 1997 The Medical Journal of Chosun University Vol.22 No.2

Background: An elevated serum sialic acid concentration has recently been shown to be a potent predictor of cardiovascular mortality in the general white population. Microalbuminuria has been shown to be a independent risk factor or predictor of diabetic nephropathy and macroangiopathy in NIDDM. Several studies have shown a elevated serum sialic acid concentrations in NIDDM patients compared with nondiabetic subjects and in IDDM patients with microalbuminuria and clinical proteinuria. Methods : We studied 29 patients with NIDDM who had a normal urinary albumin excretion rate, 16 patients who had microalbuminuria, and 23 patients with clinical proteinuria. We also investigated sialic acid levels related to blood pressure, microalbuminuna, glycemic control, lipid analysis, serum sialic acid levels, and retinopathy. Results : 1) This study shows that NIDDM patients with macroalbuminuna had significantly higher serum sialic acid concentrations than control group, normoalbummuria, and microalbuminuria group.(meand:SE : 90.41±5.6 vs. 69.7±3.8, 68.2±2.4 and 72.6±2.9mg/dl, p<0.05 respectively). 2) Multiple linear regression analysis showed that systolic blood pressure, duration of diabetes, diastolic blood pressure, triglyceride, ESR, and albumin excretion rate (AER) correlate independently with logarithmic serum sialic acid concentrations. 3) The presence or absence of diabetic retinopathy had no impact on serum sialic acid concentration. Conclusions : This study shows that the serum sialic acid concentration is raised in NIDDM patients with macroalbuminuria. And there are no relationships between serum sialic acid and diabetic retinopathy. Further study is needed to confirm the mechanism of elevated serum sialic acid in NIDDM. And prospective studies are thought to be required to evaluate whether serum sialic acid concentration can be used as a predictor of microvascular and macrovascular complications in diabetes.