0.2 ${\mu}m$ Wide-Head T-Gate PHEMT 제작에 관한 연구

전병철,윤용순,박현창,박형무,이진구,Jeon, Byeong-Cheol,Yun, Yong-Sun,Park, Hyeon-Chang,Park, Hyeong-Mu,Lee, Jin-Gu 대한전자공학회 2002 電子工學會論文誌-SD (Semiconductor and devices) Vol.39 No.1

본 논문에서는 서로 다른 dose를 갖는 이중 노광 방법을 사용한 전자빔 묘화 방법을 이용하여 0.2 ㎛의 wide-head T-게이트를 갖는 PHEMT를 제작하였다. 0.2 ㎛의 게이트 길이와 1.3 ㎛의 게이트 머리의 크기를 갖는 wide-head T-게이트를 형성하기 위하여 PMMA/P(MMA-MAA)/PMMA의 3층 레지스트 구조를 사용하였다. 0.2 ㎛의 게이트 길이와 80 ㎛의 단위 게이트 폭 및 4개의 게이트 핑거를 갖는 PHEMT의 DC 특성으로 323 ㎃/㎜의 드레인 전류 밀도 및 232 mS/㎜의 최대 전달 컨덕턴스를 얻었다. 또한 동일한 소자의 RF 특성으로 40 ㎓에서 2.91 ㏈의 S/sub 21/ 이득과 11.42 ㏈의 MAG를 얻었으며, 전 이득 차단 주파수와 최대 공진 주파수는 각각 63 ㎓와 150 ㎓였다. n this paper, we have fabricated pseudomorphic high electron mobility transistors (PHEMT) with a 0.2 ${\mu}{\textrm}{m}$ wide-head T-shaped gate using electron beam lithography by a dose split method. To make the T-shape gate with gate length of 0.2 ${\mu}{\textrm}{m}$ and gate head size of 1.3 ${\mu}{\textrm}{m}$ we have used triple layer resist structure of PMMA/P(MMA-MAA)/PMMA. The DC characteristics of PHEMT, which has 0.2 ${\mu}{\textrm}{m}$ of gate length, 80 ${\mu}{\textrm}{m}$ of unit gate width and 4 gate fingers, are drain current density of 323 ㎃/mm and maximum transconductance 232 mS/mm at $V_{gs}$ = -1.2V and $V_{ds}$ = 3V. The RF characteristics of the same device are 2.91㏈ of S21 gain and 11.42㏈ of MAG at 40GHz. The current gain cut-off frequency is 63GHz and maximum oscillation frequency is 150GHz, respectively.ively.

在日韓國人의 生活文化의 異質化와 適應過程에 關한 保健學的 硏究

金正根(Jong-Kun Kim),張昌谷(Chang-Gok Chang),林達旿(Dar-Oh Lim),金武采(Mu-Chae Kim),李州烈(Ju-Yul Lee) 한국인구학회 1992 한국인구학 Vol.15 No.2

After world war Ⅱ Japanese life expectancy has been improved remarkably, and reached the highest level in the world around late 1970's. The life expectancy of Korean has also shown tremendous improvement in recent years with about 20 year's gap from the Japanese. The reason of rapid improvement of life expectancy can be explained by changes in the structure of cause of death due to health system, living standard, social welfare, health behavior of individuals and so on. Korean in Japan is placed under different situations from both Korean in Korea and Japanese in these regards, and expected to show different picture of cause of death pattern. The objective of this study is the comparision of changing patterns of cause of death of three population groups, Korean in Japan, Korean in Korea and Japanese, and to investigate the reasons which effect to the structural difference of mortality cause with special emphasis on health ecological aspects. One of the major limitations of the Korean causes of death statistics is the under-registration which ranges about 10% of the total events, and inaccuracy of the exact cause of death. Some 20% of registered deaths were unable to classify by ICD. However, it is concluded that the Korean data are evaluated as sufficient to stand for over-viewing of trends of cause of death pattern. The evaluation is done by comparing data from registration and field survey over the same population sample. Population data of Korean in Japan differ between two sources of data; census and foreigner's registration. Correction is done by life table method under the assumption that age-specific mortality pattern would accord with that of the Japanese. The crude death rate was lowest among Korean in Japan, 5.7 deaths per 1,000 population in 1965. The crude death rates of Korean in Japan and Japanese are increasing recently influenced by age structure while Korean in Korea still shows decreasing tendency. The adjusted death rate is lowest among Japnaese, followed by Korean in Japan, and Korean in Korea. The leading causes of death of Korean in Korea until 1960's was infectious diseases including pneumonia and tuberculosis. The causes of death structure changed gradually to accidents, neoplasm, hypertensive disease, cerebro-vascular disease in order. The main difference in cause of death between Korean and Japanese is high rate of liver diseases and diabetes for both Korean in Japan and Korea. A special feature of cause of death among Korean in Korea is remakably high rate of hypertensive disease, which is assumed to be caused by physicians tendency in choosing diagnostic categories. The low ischemic heart disease and high vasculo-cerebral disease are the distinctive characteristic of the three population groups compared to western countries. Specific causes of death were selected for detailed sex, age and ethnic group comparisons based on their high death rates. Cancer is the cause of death which showed most drama tical increase in all three population groups. In Korea 20.1% of all death were caused by cancer in 1990 compared with 10.5% in 1981. Cancer of the liver is the leading cause of cancer death among Korean in Japan for both sexes, followed by cancer of the lung and cancer of the stomach, while that of Korean in Korea is cancer of the stomach, followed by cancer of the liver and cancer of the lung for male. Causes of infant mortality were examined among the three population groups since 1980 on yearly bases. For both Japanese and Korean in Japan, leading cause of death ranks as conditions originating in the perinatal period, congenital anomalies, accidents and other violent causes. Trends since 1980 for these two population groups in the leading cause of infant mortality showed no changes. On the contrary, significant changes in leading cause of death structure in Korea were observed : The ranking of leading cause of death in 1981 were congenital asnomali

최적 연료주입 모델 추종형 ${\mu}-$합성 제어기의 설계에 관한 연구

황현준,김동완,정호성,손무헌,김영훈,황기현,문경준,박준호,황창선,Hwang, Hyun-Joon,Kim, Dong-Wan,Jeong, Ho-Seong,Son, Mu-Hun,Kim, Yeung-Hun,Hwang, Gi-Hyun,Mun, Kyeong-Jun,Park, June-ho,Hwang, Chang-Sun 제어·로봇·시스템학회 1998 제어·로봇·시스템학회 논문지 Vol.4 No.2

In this paper, we design an optimal model following ${\mu}-$synthesis control system for fuel-injection of diesel engine which has robust performance and satisfactory command tracking performance in spite of uncertainties of the system. To do this, we give gain and dynamics parameters to the weighting functions and apply genetic algorithm with reference model to the optimal determination of the weighting functions that are given by the D-K iteration method which can design ${\mu}-$synthesis controller in the state space. These weighting functions are optimized simultaneously in the search domain which guarantees the robust performance of the system. The ${\mu}-$synthesis control system for fuel-injection designed by the above method has not only the robust performance but also a better command tracking performance than those of the ${\mu}-$synthesis control system designed by trial-and-error method. The effectiveness of this ${\mu}-$synthesis control system for fuel-injection is verified by computer simulation.

GIS를 이용한 소매업종 상권 반경과 중심지 이동분석

신우진,정창무,이상경 한국부동산분석학회 2002 不動産學硏究 Vol.8 No.1

This paper assesses changing patterns of the commercial power of a region and leading sectors of the movement with radial ring-based analyses of 49 categories of retail services in Kangnam-gu, Seoul. The radius of trade market area(R), as the measure of commercial power of a location, is defined as a pre-defined radial distance from the store location. Moving patterns of the regional commercial power is analysed based on the peak of overlapping density of the retail trade area every year. Findings indicate that the centers have been differentiated from each other in the form of an orderly hierarchy of places, with particular retail services developing for lower-ordered places as they reach a threshold, and leading sectors of the movement are usually retail services favored by teenagers.

유비쿼터스 환경을 위한 CASA 기반의 동적 접근 제어 기법

김경자(Kim Kyoung Ja),장태무(Chang Tae Mu) 한국컴퓨터정보학회 2008 韓國컴퓨터情報學會論文誌 Vol.13 No.4

기존의 상황 인식 서비스 모델에서는 리소스에 대한 접근 권한을 사용자의 인증으로만 리소스에 대한 접근을 허용하였으나, 사용자의 주변 상황 정보가 빈번하게 변화하는 유비쿼터스 환경에서는 상황 변화에 따른 리소스 접근제어가 제공될 필요가 있다. 본 논문에서는 사용자의 상황 정보가 변경되는 경우에 따라 리소스에 대한 접근 권한을 동적으로 제어하고자 한다. 접근 제어는 기존의 CASA(Context-Aware Security Architecture)를 기반으로 하지만 현재 서비스를 받고 있는 사용자라 할지라도 리소스 접근 권한을 제한할 수도 있다. 즉, 주위 환경 정보를 실시간으로 검사하여 주위 환경에 따라 동적으로 접근 권한을 달리 부여하여 기존의 상황 인식 서비스보다 리소스에 대한 강인한 보안 서비스를 제공한다. Conventional context-aware service models permit the access of resources only by user authentication, but the ubiquitous environments where the context information around users is changing frequently require the resource access control according to the rapid changes. This paper proposes a scheme to control access permission of resource dynamically as context information of user changes. Our access control model is based on traditional CASA (Context-Aware Security Architecture), but can restrict the access of the user already has been authorized. With the real-time checking of context information, our scheme gives different access controls according to changes in environmental information, and provides more secure services than conventional context-aware models.

자율주행 자동차의 상용화가 상업 공간구조에 미치는 영향

서현승 ( Seo Hyun-seong ),김민준 ( Kim Min-jun ),정창무 ( Jung Chang-mu ),김현정 ( Kim Hyunjung ) 한국부동산분석학회 2020 不動産學硏究 Vol.26 No.4

본 논문은 자율주행 자동차 상용화와에 따른 전국 상업 공간 구조에 미치는 영향에 대해 연구하고자 한다. 자율주행 자동차의 출현은 도시에 극적인 변화를 가져올 것으로 예상된다. 그러나 최근의 연구는 국토 공간구조의 가능한 변화 추정이 아닌, 주로 차량 기술에 초점을 맞추고 있다. 이러한 배경에서 본 연구는 일련의 시나리오를 개발하고, 자율주행 자동차로 인한 편익 발생 모델을 구축하고, 자율주행 자동차 사용으로 인한 소득 증가로 인해 국토 공간구조의 변화를 분석하는 것을 목표로 한다. 문헌 검토를 기반으로 네 가지 시나리오를 설정하였으며, 시나리오 별 자율주행 자동차의 상용화 정도를 예측하기 위해 주요 요소의 계수를 포함한다. 각 시나리오 별 편익 계산한 것을 바탕으로 상권의 소득 및 직원 증가에 따른 전국 상업 공간 구조의 변화를 제시한다. 본 논문의 시뮬레이션 결과 자율주행 자동차가 초기 단계에서는 특정 지역에만 분포되어 있기 때문에 상업 연면적 증가량의 지역적 격차가 증가하는 것을 보여준다. 하지만 자율주행 자동차 보급률이 증가함에 따라 전국적으로 상권의 매출, 고용자 수 증가로 교외 지역도 발달하여 지역 불균형 개발이 감소한다. 장기적으로 시간이 지남에 따라 지역적 격차가 줄어들고 국토의 균형적 개발이 가능할 것으로 예상된다. This paper aims to investigate the relationship between commercialization of autonomous vehicles and its influence on commercial spatial structures nationwide. The emergence of autonomous vehicles is expected to bring about dramatic changes in our cities. However, recent studies mainly focus on the technology of vehicles, not the estimation of possible changes. For this reason, our study aims to develop a set of scenarios, build forecasting model for benefits of autonomous cars, and analyze the changes in territory due to the increased income from using autonomous vehicles. Four different scenarios have been identified based on literature review, containing different coefficients of the main elements for forecasting future commercialization of autonomous vehicles. From the benefits we concluded in each scenarios, which were calculated through main elements, we propose the change in commercial spatial structures nationwide due to the increased income and employee. Our simulation results show that in the early stage, regional gap increases since autonomous vehicles are only distributed in specific area. However, as autonomous vehicles’ dissemination rate increases, suburban area also develop due to increasement in revenue and number of employee, leading to reducement in territory unbalanced development. Regional gap decreases as time passes and territory balanced development increases in the long run.

상이동 촉매에 의한 염화벤질과 티오시안산 칼륨의 치환 반응에 관한 반응속도론

장승현,윤무홍 대구대학교 산업기술연구소 1986 産業技術硏究 Vol.5 No.-

The catalytic effects of several phase transfer catalysts on the displacement reaction of benzyl chloride with aqueous potassium thiocyanate in a two phase system have been determined. The kinetics are linearly dependent on catalyst concentration. The examination of the relative rates with various catalysts showed the following trend: NH₄Cl<PhCH₂N(CH₃)₃Cl<18-Crown-6<PhCH₂N(C₂H_(5))₃Cl<P.E.G.<(n-Bu)₄NCl<CTMAB Kinetic analyses of the data suggest that rate determining step occurs in the interphase microemulsion comprisiting of the surfactant, the anion and the apolar solvents. Increased rate was also observed with more polar organic solvents.

서울市 乘用車 要需推定模型에 관한 硏究

元濟戊,吳昌默 건국대학교 행정대학원 1987 建國大學校 行政大學院 硏究論叢 Vol.15 No.-

韓國의 第四紀地層

崔茂藏 全南大學校 湖南文化硏究所 1977 호남학 Vol.9 No.-

Anti-inflammatory Effect of LFR on LPS-stimulated THP-1 Cells

정승기,Sul, Mu-Chang,Kim, Hong-Yeoul,Roh, Young-Lae,Jung, Hee-Jae,Jung, Sung-Ki 대한한방내과학회 2009 大韓韓方內科學會誌 Vol.30 No.2

Background and Objective: Luffae Fructus Retinervus (LFR) is used for investigating symptoms of inflammation. We have evaluated the anti-inflammatory effect of LFR by analyzing the expression of pro-inflammatory cytokines. Materials and Methods : We differentiated THP-l cells into macrophage-like cells by treatment with PMA. Inflammation was induced by treatment with LPS and PMA. We determined the safe concentration of LFR by using the MTS and MTT assays and using PD 98059 as a negative control for comparison of the anti-inflammatory effect of LFR. Results : The MTS and MTT analysis showed that the cell survival rate was >80% within the LFR concentration range of 10-100 ng/ml and began to decrease to >80% at 1 ${\mu}g/ml$. By RT-PCR analysis, the gene expression of TNF-${\alpha}$, IL-8, TGF-${\beta}$, IL-6, IL-${\beta}$1, and IL-10 levels were down-regulated when monocyte-derived macrophages were treated with concentrations of LFR between 10 ng/mL and 100 ng/mL. Conclusion : We conclude that LFR exerts an anti-inflammatory effect by inhibiting the expression of pro-inflammatory activity. The results suggest a promising way to treat general inflammatory diseases.