양성자 주입 기술을 이용한 초고속 회복 다이오드의 제작

이강희,김병길,이용현,백종무,이재성,배영호,Lee, Kang-Hee,Kim, Byoung-Gil,Lee, Yong-Hyun,Baek, Jong-Mu,Lee, Jae-Sung,Bae, Young-Ho 한국전기전자재료학회 2004 전기전자재료학회논문지 Vol.17 No.12

Proton irradiation technology was used for the improvement of power diode switching characteristics. Proton irradiation was carried out at the energies of 2.32 MeV, 2.55 MeV, 2.97 MeV so that the projection range of irradiated proton would be at the metallurgical junction, depletion region and neutral region of pn diode, respectively. Dose conditions were varied into three conditions of 1${\times}$10$^{11}$ cm$^{-2}$ , 1${\times}$10$^{12}$ cm$^{-2}$ , 1${\times}$10$^{13}$ cm$^{-2}$ at each condition of energies. Characterization of the device was performed by I-V(current-voltage), C-V(capacitance-voltage) and trr(reverse recovery time) measurement. At the optimum condition of irradiation, the reverse recovery time of device has been reduced about 1/5 compared to that of original un-irradiated device.

토복령(土茯笭)이 RAW264.7 대식세포주에서 산화질소 억제에 미치는 영향

이강희,정준희,김이화,이재혁,Lee, Kang-Hee,Jung, Jun-Hee,Kim, Ee-Hwa,Lee, Jae-Hyuk Society for Meridian and Acupoint 2009 Korean Journal of Acupuncture Vol.22 No.2

Objectives : 본 연구의 목적은 제습, 해독, 통리관절등의 효능이 있는 토복령이 RAW264.7 대식세포주에서 lipopolysaccharide(LPS)로 처치하여 생성되는 nitric oxide(NO)와 prostaglandin $E_2$($PGE_2$)에 억제작용이 있는지 관찰하고자 하는 것이다. Methods : 토복령이 RAW264.7 대식세포주에 세포독성이 유무를 관찰하기 위하여 농도별 MTT assay를 수행하여 세포생존율을 측정하였다. 또한 LPS로 염증유발된 RAW264.7 대식세포주에서 토복령의 농도별 처치가 NO 및 $PGE_2$ 생성억제에 미치는 영향을 관찰하고자 NO 및 $PGE_2$ assay를 수행하였다. Results : 토복령의 농도별 처치가 RAW264.7 대식세포주에서 세포독성을 유발하는지 MTT assay로 측정한 결과 세포독성은 관찰되지 않았으며, 토복령은 LPS처치로 인하여 증가된 NO 및 $PGE_2$ 생성을 통계학적으로 유의하게 감소시킴을 관찰하였다. Conclusions : 본 연구를 통하여 토복령은 RAW264.7 대식세포주에서 LPS로 유도된NO 및 $PGE_2$ 생성을 효과적으로 억제시킴으로써 추후 염증질환의 치료제로서 가능성을 확인하였다.

강화지역 청소년의 4년간 혈청 지질의 변화와 지속성

이강희,서일,지선하,남정모,김성순,심원흠,하종원,김석일,강형곤,Lee, Kang-Hee,Suh, Il,Jee, Sun-Ha,Nam, Chung-Mo,Kim, Sung-Soon,Shim, Won-Heum,Ha, Jong-Won,Kim, Suk-Il,Kang, Hyung-Gon 대한예방의학회 1997 Journal of Preventive Medicine and Public Health Vol.30 No.1

소아에서부터 청소년기까지 혈청 지질의 지속성(tracking)은 서구에서 행해진 연구들에 의해서 이미 잘 알려져 있으나 국내에서는 이에 관한 연구가 거의 이루어지지 않았다. 본 연구는 우리나라 청소년의 혈청 지질치의 변화를 조사하고 지속성이 있는지를 분석하였다. 연구대상은 경기도 강화군에서 진행하고 있는 강화 아동 혈압 코호트(719명)의 청소년들로 12세, 14세, 16세 세 번에 걸쳐서 공복 후 혈액검사(혈청 총 콜레스테롤, 중성지방, LDL 콜레스테롤, HDL 콜레스테롤을 포함)와 신체계측을 시행하였다. 이 중 3번의 혈액 검사에서 10시간 이상의 공복이 확인된 청소년 309명 (남자 162명, 여자 147명)을 최종 연구대상으로 선정하였다. 연구대상이 된 청소년들과 연구대상에서 제외한 청소년들의 12세때 초기 검사치들을 t 검정을 이용하여 서로 비교한 결과 통계학적으로 유의한 차이는 없었다. 연구방법은 우선 혈청 지질치의 변화양상을 보기 위하여 각 검사 년도간에 반복 측정된 분산분석을 시행하였다. 각 혈청지질의 지속성을 보기 위해서는 첫께, 초기값을 바탕으로 사분위 집단으로 나누어 각 사분위 집단의 혈청지질치가 매 검사 연도마다 어떻게 변하는 지를 그림으로 나타내었다. 둘째, 혈청지질치의 검사 시기사이의 스피어맨 상관계수를 구하였다. 그리고 마지막으로 각 검사 년도의 혈청지질치를 사분위 집단으로 구분하여 초기검사에서 가장 위험도가 큰 집단에 속한 사람들이 지속적으로 위험도가 큰 집단에 속하는 백분율을 계산하였다. 연구결과 남녀 모두 4년간 세 번의 검사에서 혈청 총 콜레스테롤은 남자가 초기검사에서 $160.7{\pm}25.3mg/dl$, 최종 추적검사에서 $150.0{\pm}27.8mg/dl$, 여자가 초기검사에서 $168.8{\pm}29.7mg/dl$, 최종 추적검사에서 $168.8{\pm}29.7mg/dl$, 중성지방은 남자가 $98.0{\pm}45.7mg/dl$에서, $114.1{\pm}67.9/mg/dl$로, 여자가 $109.9\geq37.1mg/dl$에서, $104.9{\pm}47.6mg/dl$로, LDL 콜레스테롤은 남자가 $93.6{\pm}21.2mg/dl$에서, $83.0{\pm}25.0mg/dl$로 여자가 $83.0{\pm}25.0mg/dl$에서, $94.7{\pm}24.4mg/dl$로, HDL 콜레스테롤은 남자가 $47.6{\pm}9.1mg/dl$에서, $44.2{\pm}9.4mg/dl$로, 여자가 $48.8{\pm}10.0mg/dl$에서, $47.8{\pm}11.3mg/dl$ 변화하였다. 반복 측정한 분산분석 결과 남녀 모두 4년 동안 혈청 총 콜레스테롤, LDL 콜레스테롤, HDL콜레스테롤이 통계적으로 유의하게 감소하였다. 특히 남자 LDL 콜레스테롤은 두 번의 추적검사에서 모두 감소한 것으로 나타났다. 중성지방은 남자에서는 지속적으로 증가하였고 여자에서는 변화가 없었다. 같은 연령에서 남녀간의 각 혈청지질치를 비교해보면 중성지방을 제외하고는 모두 여자가 남자보다 더 컸다. 혈청 지질의 초기 검사와 최종 검사간의 스피어맨 상관분석과 각 혈청 지질치의 위험도가 가장 큰 사분위집단에 잔류하는 백분율을 보면 지속성이 존재하였다. 혈청 총 콜레스테롤과 HDL 콜레스테롤에서 각 시기의 검사치들의 상관계수는 남자가 0.6 이상, 여자가 약 0.7 이상이었으며 통계적으로 유의하였다. 첫 번께 검사에서 위험도가 가장 큰 사분위 집단에 속한 사람 중 두 번째 검사에서도 위험도가 가장 큰 사분위 집단에 속한 백분율은 여자의 중성지방(42.9%)을 제외하고는 모두 50%이상이었다. 이들이 세 번째 검사에서도 같은 사분위 집단에 잔류한 백분율은 It has been known that there is a tracking phenomenon in the level of serum lipids. However, no study has been performed to examine the change and tracking of serum lipids in Korean adolescents. The purpose of this study is to examine the changes of serum lipids in Korean adolescents from 12 to 16 years of age, and to examine whether or not there is a tracking phenomenon in serum lipids level during the period. In 1992 serum lipids(total cholesterol(TC), triglyceride(TG), LDL cholesterol(LDL-C), HDL cholesterol(HDL-C)) were measured in 318 males, 365 females who were 12 years of age in Kangwha county, Korea. These participants have been followed up to 1996 and serum lipids level were examined in 1994 and 1996. Among the participants 162 males and 147 females completed all three examinations in fasting state. To examine the effect of eliminating adolescents with incomplete data, we compared serum lipids, blood pressure and anthropometric measures at baseline between adolescents with complete follow-up and adolescents who were withdrawn. To examine the change of serum lipids we compared mean values of serum lipids according to age in males and females. Repeated analysis of variance was used to test the change according to age. We used three methods to examine the existence of tracking. First, we analyzed the trends in serum lipids over 4-year period within quartile groups formed on the basis of the first-year serum lipids level to see whether or not the relative ranking of the mean serum lipids among the quartile groups remained in the same group for 4-year period. Second, we quantified the degree of tracking by calculating Spearman's rank correlation coefficient between every tests. Third, the persistence extreme quartile method was used. This method divides the population into quartile groups according to the initial level of blood lipids and then calculates the percent of the subjects who stayed in the same group at follow-up measurement. The decreases in levels were noted during 4 years for TC, LDL-C, primarily for boys. The level of HDL-C decreased between baseline and first follow-up for both sexes. Tracking, as measured by both correlation coefficients and persistence extreme quartiles, was evident for all of the lipids. The correlation coefficients of TC between baseline and 4 years later in boys and girls were 0.55 and 0.68, respectively. And the corresponding values for HDL-C were 0.58 and 0.69. More than 50% of adolescents who belonged to the highest quartile group in TC, HDL-C and LDL-C at the baseline were remained at the same group at the examination performed 2 years later for both sexes. The probabilities of remaining at the same group were more than 35% when examined 4 years later. The tracking phenomenon of TG was less evident compared with the other lipids. Percents of girls who stayed at the same group 2 years later and 4 years later were 42.9% and 25.7%, respectively. It was evident that serum lipid levels tracked in Korean adolescents. Researches with longer follow-up would be needed in the future to investigate the long-term change of lipids from adolescents to adults.

핵연료집합체 기계적특성 시험시설 구축과 기능시험

이강희,강흥석,윤경호,양재호,Lee, Kang-Hee,Kang, Heung-Seok,Yoon, Kyung-Ho,Yang, Jae-Ho 한국압력기기공학회 2016 한국압력기기공학회 논문집 Vol.12 No.1

Fuel assembly's mechanical characterization test facility (FAMeCT) in KAERI was constructed with upgraded functional features such as increased loading capacity, underwater vibration testing and severe earthquake simulation for extended fuel design guideline. This facility is designed and developed to provide out-pile fuel data for accident analysis model and fuel licensing. Functional tests of FAMeCT were performed to confirm functionality, structural integrity, and validity of newly-built fuel assembly mechanical test facility. Test program includes signal check of data acquisition system, load delivering capacity using real-sized fuel assemblies and a standard loading cylindrical rigid specimen. Fuel assembly's lateral bending test was carried out up to 30 mm of pull-out displacement. Limit case axial compression loading test up to 33 kN was performed to check structural integrity of UCPS (Upper Core Plate Simulator) support frame. Test results show that all test equipment and measurement system have acceptable range of alignment, signal to noise ratio, load carrying capacity limit without loss of integrity. This paper introduces newly constructed fuel assembly's mechanical test facility and summarizes results of functional test for the mechanical test equipment and data acquisition system.

교육시설의 옥상방수 열화도 진행 모델에 관한 연구

이강희,채창우,류수훈,Lee, Kang-Hee,Chae, Chang-U,Ryu, Soo-Hoon 한국교육시설학회 2017 敎育施設 Vol.24 No.6

Education facilities have much affect to make a good condition for the learning environment. Therefore, various approaches have been conducted to improve the physical, social and educational achievement. Especially, the physical aspect is very important to get rid of the building defect and improve the student their learning environment. For these, it needs to explain the performance and function of components and materials, which is linked with the deterioration degree. The deterioration degree is a imperative factor to make a decision whether the component would be repaired or not and to provide the repair scope of its component. In this paper, it aimed at making the deterioration degree model of roof proof under the hypothesis of which deterioration degree would be equal the repair cost at this time. Results of the study are shown that first, the $3^{rd}$ function is most proper to explain the deterioration degree model among 11 functions in view of resulted statistics. Second, the inflection of deterioration is shown at 15yr of the elementary school and 13yr of the middle and high school. This study has a limit of disclassification of the component or materials and it is, therefore, favorable to include the classification of waterproof material and work. These results would make a change from the breakdown maintenance to preventive maintenance and give a decent the learning environment for student.

솔-젤 합성에 의한 직접 메탄올 연료전지용 고분산 Pt-Ru/C 음극 촉매의 제조

이강희,김일곤,박태진,서동진,Lee, Kang-Hee,Kim, Il-Gon,Park, Tae-Jin,Suh, Dong-Jin 한국전기화학회 2003 한국전기화학회지 Vol.6 No.1

직접 메탄을 연료전지의 음극 촉매로 사용되는 Pt-Ru/C를 솔-젤법을 이용하여 크라이오젤 및 에어로젤 형태로 제조하였다. 탄소의 원료가 되는 유기물의 종류에 따라 B종의 촉매를 제조하였으며 XRD분석에 의해 금속이 탄소담체 위에 고분산되어 있음을 확인하였다. 초임계건조, 탄화. 환원 공정을 거쳐 완성된 에어로젤 촉매의 전극 활성은 Cyclic voltametry를 이용한 half cell test를 통하여 평가하였다. 그 중 Phloroglucinol-Formaldehyde(PF) 형의 촉매가 가장 우수한 활성을 보였으며 내구성 또한 양호하였다. Cryogel and aerogel Pt-Ru/C were synthesized by the sol-gel process for the electrooxidation of methanol. From XRD analysis, it was found that the catalysts had highly dispersed Pt-Ru alloys on carbon support although high temperature treatments have been conducted. Electrocatalytic activities of 3 type aerogel catalysts were investigated in half cell experiments by cyclic voltammetry. Among them, Phloroglucinol-Formaldehyde(PF) type catalyst shows the highest activity. From the results of deactivation test for each catalysts, the aerogel catalysts are found to have excellent durability compared with those prepared by colloidal method.

공동주택 구성재의 경제적 수선형태 설정 연구

이강희,채창우,Lee, Kang-Hee,Chae, Chang-U 한국주거학회 2006 한국주거학회 논문집 Vol.17 No.5

Building components have been deteriorated by various factors such as location, a building type, a surrounding environment and so on. In addition, each component has a peculiar characteristics, compared with other components in properties of matter an used part. Building components would be required to maintain its function and performance to provide the resident with a decent living condition. It is important to decide the repair time, scope and a required cost in repair plan, considering the each component's characteristics. In this parer, it aimed at providing the economic repair pattern to analyze the relation of the time-elapse and the cumulative repair cost in the apartment housing using 3rd quadratic function. Results of the study are as follows: First, the shape of the function for the economic repair is classified into two type. One is the continuous increase type of the cumulative cost which properly means the iterative repair type after built. The other is that the function has the maximum state at a point which means one-repair after its repair would be delayed to a scheduled time. Second, the iterative repair pattern would include window, roof proof, lighting and water supply pipe. The other repair pattern would include the paintings, heating pipe and sign board.

공동주택 구성재의 내용년수 산정방법에 관한 연구

이강희,장정희,채창우,Lee Kang-Hee,Chang Jung-Hee,Chae Chang-U 한국주거학회 2005 한국주거학회 논문집 Vol.16 No.5

The performance of building should be deteriorated with time while the building would maintain and manage the function and performance to get a living condition. For the efficient maintenance of the building, the repair cycle would be provided and applied during the service-life time. The service-life time of the building components would be needed to determine the repair time and the repair scope. The service-life time of the building components would be calculated with the 1st repair time and the recovery rate of the performance, considering the recovery rate after repaired. In this paper, the 1st repair time would be estimated with the normal probability distribution, choice probability and 3rd quadratic function. The recovery rate of the building components assumes various level according to the research target and utility area. The results of this study are as follows ; first, most of the components of the building work would range about 30 years in the service-life time and the components of the mechanical works range from 28 years to 37 years, those of the electrical works would be about 31 years.

임대공동주택 구성재의 열화도 패턴에 관한 연구

이강희,Lee Kang-Hee 한국주거학회 2006 한국주거학회 논문집 Vol.17 No.4

Most of buildings have been deteriorated with time-elapse by reflection of the building location, material, environmental circumstances and so on. The performance would go down and be demolished if anything could not be done after constructed. The maintenance should be required to preserve a decent living condition or improve a inferior condition by various plans and practices. The maintenance plan needs various data such as a repair scope, a repair time, a forecasted cost, a plan of management and so forth. Among the above required data for planning the maintenance, the deterioration characteristics of the building components would be first analyzed. The deterioration pattern would be a key role to affect and make a maintenance plan. In this paper, it aimed at classifying the deterioration patterns of building components. A deterioration pattern would be analyzed between the cumulative repair cost and time-elapse and modeled with these relations. A deterioration patterns are classified into 4 types-a accelerated type, a straight type, a temporary type and a slowly type. As a result of this research, a accelerated type includes window, window frame, general paintings, general water proofing in building components. A straight type includes the lacquer paintings, furnishings in building components and water supply pipe, boiler, sanitaries in mechanical facilities and lighting in electric facilities. Based on these research results, further study should be conducted to include any other components and an estimating model.

공동주택 구성재의 예상수선시기 범위 설정 연구

이강희,Lee Kang-Hee 한국주거학회 2006 한국주거학회 논문집 Vol.17 No.2

Building would be deteriorated with time elapse, influenced by its geographic situation, climate and other environmental conditions. In addition, the systematic maintenance could be provided to keep the resident a recent living condition. The existing breakdown maintenance will be changed into the preventive maintenance. The preventive maintenance is required to get the repair time, the repair scope and frequency. In this paper, it aimed at providing the repair time range over the building components, utilizing the relation between the determination curve and the performance recovery through repair. Results of this study are as follows : First, the forecast of the repair time over the building components could be calculated and equalized with the deterioration and performance degree. Second, the repair time range of building components would be provided into five categories and 3rd repair time. Results of this study will set up the long-term repair plan of building, and finally keep an housing condition comfortable.