중발열량 석탄 가스를 사용하는 복합발전 사이클의 성능 및 NOx 배출 특성

이찬,윤용승,Lee, Chan,Yun, Yong-Seong 한국에너지학회 2000 에너지공학 Vol.9 No.4

증발열량 석탄가스 연료를 사용하는 석탄가스와 복합 발전 플랜트의 성능 및 NOx 배출량을 동시에 예측하기 위한 모사 방법을 제시하였다. 본 방법은 복합 사이클의 열역학적 해석 기법을 토대로, 석탄가스화 복합발전 플랜트의 시스템 연계 및 석탄가스 연소에 의한 탈설계점 효과를 예측하는 모델들을 포함하고 있다. 본 방법에 의한 전산 모사 결과와 천연가스를 사용하는 복합발전소의 실제 시험 결과를 비교함으로써, 본 방법의 예측정확도를 검증하였다. 본 모사 방법을 이용하여, 서로 다른 4가지 석탄가스 연료에 대해, 공기 분리장치와의 다양한 연계 설계 조건에 따른 석탄가스화 복합발전 플랜트의 전체 성능, 운전 안전성 및 NOx 배출 특성들을 비교, 검토하였다.

중발열량 가스 대체 시 가스터빈 연소기의 연소 및 NOx 배출 특성

이찬,서제영,Lee, Chan,Seo, Je-Young 한국에너지학회 2003 에너지공학 Vol.12 No.4

IGCC용 가스터빈 연소기의 중발열량 가스 연료 대체성 및 호환성 검토를 위한 전산유체역학적 연구를 수행하였다. 연소기 전산해석 방법은 기존의 상용 CFD코드의 해석체계에 중발열량 가스연료의 화학반응 모델 및 fuel NOx 모델등을 추가적으로 결합하여 구성하였다. 본 해석방법을 이용하여, 천연가스와 IGCC 용 대체가스(석탄가스, 중잔사유 가스) 연소시의 연소기 내부 유동속도, 화학종, 온도 분포들과 화염 형상 및 거동을 비교하였고, 더 나아가 NOx 생성특성과 터빈과의 matching 조건도 분석하였다. 이러한 전산해석결과들을 바탕으로, 본 연구는 중발열량 가스를 대체연료로 사용하는 IGCC용 가스터빈 연소기의 설계 개선 및 재설계 방향을 제시하였다. A CFD (Computational fluid Dynamics) research is conducted for the investigation of the fuel alteration of MBTU (medium-Btu) gas in IGCC gas turbine combustor. The computational analysis method of the gas turbine combustor is constructed by incorporating MBTU gas reaction and fuel NOx models into commercial CFD code. With the use of the present analysis method, comparisons are made on the flow velocity, the chemical species and the temperature distributions, and on the flame shape and behavior of gas turbine combustor firing natural gas and MBTU gases (coal gas, heavy residue oil gas). Furthermore, the NOx formation characteristics and the turbine matching condition of the combustor are analyzed. Based on the computed analysis results, the present study provides the directions for the redesign and the design modification of IGCC gas turbine combustor firing MBTU gas as alternative fuel.

다기능성 환원-산화 그래핀/실크 피브로인 기반 센서

이찬의(Chanui Lee),조현호(Hyeonho Cho),이차범(ChaBum Lee),이상민(Sangmin Lee),김승한(Sunghan Kim) 대한기계학회 2023 대한기계학회 춘추학술대회 Vol.2023 No.11

경쟁력 강화를 위한 월곡중학교 학교브랜드 아이덴티티의 상징성 연구

이찬서(Lee, Chan Seo),엄기준(Um, Ki Joon) 한국디자인리서치학회 2017 한국디자인리서치 Vol.2 No.1

Recent schools have been focusing on promoting students for the recruitment of students. In this period of new change in the education field, the value of the symbol for the purpose of advertisement and publicity like the general corporation is increased. However, it differs from the basic ideology of the school, which is rooted in education. The ideal part of education and public relations is the symbol of the school, or UI(University Identity). Private schools are currently in a state of improvement for branding, but in the case of public schools, school UIs do not stand out. The UI of the existing school emphasizes not only the meaning of symbolism but also the meaning of the founder of the foundation or the foundation. The symbolism that only the school has is not shown much. It is easy to see the image of the school and the goal of the school pursued by anyone who persuades the tradition and the symbolism of the school education and induces the branding to take along with the UI, I hope that the students will be able to provide new issues in the educational field by improving the symbolism of the students and making them proud of the school and being satisfied with the school. 근래의 학교는 학생의 수가 줄어 학생모집을 위한 홍보에 초점을 맞추고 있다. 이런 교육현장의 새로운 변화의 시기에 학교가 일반기업체처럼 광고와 홍보를 목적으로 하는 상징성의 가치는 커졌다고 할 수 있다. 그러나 교육에 근본을 두는 학교의 기본 이념과는 차이가 있다, 이런 시기에 교육과 홍보를 이상적부분이 바로 학교의 상징적 마크, 즉 UI(University Identity)라고 생각되어진다. 사립학교는 이미 브랜드화를 위해 학교UI에 중요성을 인식하고 현재 개선 상태이나, 공립학교의 경우 학교UI는 크게 두드러지지 않는다. 기존 학교의 UI는 상징성의 의미보다는 전통성이나 재단의 설립자가 정한 의미를 강조하는 측면이 높다보니 학교만이 가지고 있는 상징성은 크게 나타내지지 않는 단점 을 가지고 있다. 학교교육이 가지고 있는 전통과 상징성을 계승시키며, 브랜드화를 함께 가지고 갈 수 있도록 유도 하여 학생들이 학교에 대한 자부심과 학교가 추구하는 전통과 역사, 이념적 목표를 상징적으로 담아 낼 수 있다면, UI를 보기만 해도 누구든 그 학교의 이미지와 학교가 추구하는 교육의 목표를 쉽게 알 수 있고, 교육의 특수성과 학교의 상징성을 동시에 개선해 학생이 학교에 자부심을 가지고 학교에 만족하는 생활이 됨으로서 교육현장의 새로운 이슈를 제공할 수 있을 것을 기대 해 본다.

석탄가스화 복합발전용 가스터빈의 성능 평가

이찬,이진욱,윤용승,Lee, Chan,Lee, Jin-Wook,Yun, Yong-Seung 한국유체기계학회 1999 한국유체기계학회 논문집 Vol.2 No.1

This simulation method is developed by using GateCycle code for the performance evaluation of the gas turbine in IGCC(Integrated Gasification Combined Cycle) power plant that uses clean coal gas fuel derived from coal gasification and gas clean-up processes and it is integrated with ASU(Air Separation Unit). In the present simulation method, thermodynamic calculation procedure is incorporated with compressor performance map and expander choking models for considering the off-design effects due to coal gas firing and ASU integration. With the clean coal gases produced through commercially available chemical processes, their compatibility as IGCC gas turbine fuel is investigated in the aspects the overall performance of the gas turbine system. The predictions by the present method show that the reduction of the air extraction from gas turbine to ASU results in a remarkable increase in the efficiency and net power of gas turbines, but it is accompanied with a shift of compressor operation point toward to surge limit. In addition, the present analysis results reveal the influence of compressor performance characteristics of gas turbine have to be carefully examined in designing the ASU integration process and evaluating the overall performance parameters of the gas turbine in IGCC Power plant.

초음속충돌제트의 열전달에 관한 실험적 연구

이찬,정명균,Lee, Chan,Chung, Myung-Kyoon 대한기계학회 1991 대한기계학회논문집 Vol.15 No.1

본 연구에서는 로켓노즐로 부터 분출되는 고온의 초음속제트가 45˚로 경사진 평판으로 분사되는 경우의 열전달을 측정하였다.고온의 제트가 충돌하는 평판표면 의 고온과 열유속을 측정하는 것이 거의 불가능하므로, 국소적열전달은 국소적 준 1차 원 열전도모형을 평판표면 아래에서 측정한 온도자료에 적용하여 구하였다. An experiment was conducted to determine the local heat transfer from a supersonic hot jet impinging at 45.deg. to a plate surface. A semi-analytic method was used to determine the Nusselt number from experimental data. The results indicates that the location of the peak heat transfer is displaced from the geometric center of the axisymmetric jet and that the radial variation of the local heat transfer is steeper than that in the subsonic impinging jet. In the stagnation region, the heat transfer from the supersonic impinging jet is about 10 times larger than that from the subsonic one, while the heat transer away from the stagnation region is of the same magnitude as that of the in compressible turbulent radial wall jet.

임상연구에서 사용되고 있는 NRS에 대한 분석 : 무작위대조군연구를 중심으로

이찬,조임학,허기윤,강희경,김민화,한창우,김소연,최준용,박성하,윤영주,홍진우,권정남,이인,Lee, Chan,Cho, Im-hak,Heo, Gi-yoon,Kang, Hee-kyung,Kim, Min-hwa,Han, Chang-woo,Kim, So-yeon,Choi, Jun-yong,Park, Seong-ha,Yun, Young-ju,Hong, Jin-woo 대한한방내과학회 2021 大韓韓方內科學會誌 Vol.42 No.4

Objectives: The purpose of this study was to review the status of numeric rating scale (NRS) usage and suggest the potential for use in multicenter retrospective studies of various diseases. Methods: Articles published from 2011 to 2021 that used the keywords "NRS", "Multi-center", and "RCT" were identified in foreign databases, including EMBASE, PubMed, CENTRAL. The articles were analyzed according to their use of "NRS" by symptoms and by disease group using the major classifications of the Korean Standard Classification of Diseases (KCD-7). Results: Classification by symptom in a total of 288 articles illustrates that the NRS was not only commonly used in pain evaluation but also for non-pain symptoms. In usage with non-pain symptoms, chief complaint of patients was the most common at 79%, and other factors included treatment satisfaction, evaluation of daily life, and sleep quality. In disease classification according to the KCD-7, the NRS was commonly used in connection with musculoskeletal and connective tissue diseases but was also utilized in various other disease groups. Conclusions: This study confirms usage of the NRS in multi-center RCTs, as the NRS was widely used in all types of diseases and symptoms. Considering the result and the advantages of the NRS, it is recommended for use as a daily evaluation tool for the collection of common data in multicenter retrospective studies.

저 발열량 석탄가스 연료의 화염 안정성 및 NOx 발생 특성에 관한 실험적 연구

이찬,김용철,Lee, Chan,Kim, Yong-Chul 한국에너지학회 2000 에너지공학 Vol.9 No.2

저발열량 석탄가스의 thermal/fuel NOx 생성특성과 화염 안정성을 규명하기 위한 실험적 연구를 수행하였다. 저발열량 합성 연료 가스는 일산화탄소, 수소, 질소 및 암모니아를 천연가스 연료와 동일한 입열량을 가지도록 혼합하여 만들었고 , 합성가스는 평면 화염 버너를 공급하여 태웠다. 특정한 합성가스에 대해 당량비를 변화시켜 가며, 비화 또는 역화에 의한 화염안정성을 규명하였고 안정된 화염 영역을 정의하였다. 저발열향 합성가스의 연소시 발생하는 thermal 및 fuel NOx를 측정하여 천연가스 연소시의 경우와 비교하였다.

ROS 기반의 자율주행 서빙로봇 개발에 대한 연구

이찬해(C. H. Lee),안태준(T. J. Ahn),정해진(H. J. Jeong),이현우(H. W. Lee),정명진(M. J. Chung) Korean Society for Precision Engineering 2022 한국정밀공학회 학술발표대회 논문집 Vol.2022 No.10

Nitrous Oxide - Oxygen 의 장기노출이 백서 혈구세포에 미치는 영향에 관한 실험적 연구

이찬일(Chan Il Lee) 대한악안면성형재건외과학회 1984 Maxillofacial Plastic Reconstructive Surgery Vol.6 No.1

N/A The purpose of this study was to observe hematologic alterations following prolonged inhalation of the nitrous oxide-oxygen in rats. For this study, 56rats weighing an average of 150gm were selected and devided into control and experimental groups. The experimental groups were then categorized as fallows: 1. 20 percent nitrous oxide-80 percent oxygen group. 2. 50 percent nitrous oxide-50 percent oxygen group. 3. 70 percent nitrous oxide-30 percent oxygen group. The experimental groups were exposed within closed chamber to an atmosphere of above concentrations at a flow of 2L.fminute for either 8 hours (Intermittent group) or 24 hours (Continuous group) daily for various period. Carbon dioxide was absorbed by soda 1ime. Whenever the chamber was opened for addition of food and water or removal of animals the inflow rate of nitrous oxide-oxygen was increased m 10L./minute for 5 minutes, At the 1st, 3rd, 6th, and 7th days, experimental groups were sacrificed by giving Ketamine HCL of 1mg/100gm of body weight with intramuscular injection. When the animals anesthetized, the thoraces were opened and blood samples were drawn into a 5ml disposable syringe from the heart then placed in a bottle containing E.D.T.A. This blood samples were used for counts of red blood cell, white blood cell, hematocrit, hemoglobin, and used to make a smear for white blood cell differential counts and studies. These counts were immediately performed en the sacrificed time. The red blood cell and white blood cell counts were made by standard method and the differential leukocyte counts were conducted by examination of blood films stained with Wrights stain. The hemoglobin concentration was determined with Corning 950 Hemoglobinmeter (Corning Co., U.S.A.) and the hematocrit value was determined by the method of capillary hematocrit. The mean corpusclar volume (M.C.V.), mean corpuscular hemoglobin (M.C.H.), and mean corpuscular hemoglobin concentration (M.C.H.C.) were calculated by the method of Wintrobe. The following results were obtained: 1. The significant eviedence of leukopoietic depression was found on the 5th and 7th days of continuous exposure groups to 50%, 70% nitrous oxide. (0.82±0.18 -2.65±0.15 10(3)/Cu, mm., p<0.01) 2. Red blood cell counts were within normal limits. 3. Hemoglobin concentration suggested a significant decrease on the 7th day dxperimental groups. (10.5±0.2 -11.6±Omg/100ml., p<0.01) 4. Hematocrit values suggested a significant decrease on the 3rd, 5th and 7th days of continuous exposure to 70% nitrous oxide. (29.0±1.0 -31.25±0.5%, p< 0.01) 5. Mean corpuscular volume (M.C.V.) values suggested a significant decrease on the 5th and 7th days of all experimental groups. (39.6±1.29 -52.78±2.46 Cu. μ., p<0.01) 6. Mean corpuscular hemoglobin (M.C.H.) values suggested a significant decrease on the 1st, 7th days of continuous exposure groups to 20%, 50% nitrous oxide. (13.13±0.05 -16.61±0.2 μμg., p<0.01) 7. The significant evidence of neutropenia was found on the 3rd day to 20% continuous, 70% intermittent exposure groups and the 5th, 7th days all experimental groups. (0-8.75± 5.29%. p<0.01) 8. Lymphocytes were relatively resistant to nitrous oxide in the all experimental groups.