屠殺方法 및 死後時間經過에 따르는 조직비반세포의 出現狀況에 關한 實驗的硏究

李永哲(Young Chul Lee) 대한외과학회 1964 Annals of Surgical Treatment and Research(ASRT) Vol.6 No.5

대형주강품에 대한 CAE 시스템 개발 연구

이영철,이두호,김종기,소찬영,최정길,홍준표 ( Young Chul Lee,Doo Ho Lee,Jong Ki Kim,Chan Young So,Jeong Kil Choi,Chun Pyo Hong ) 한국주조공학회 1997 한국주조공학회지 Vol.17 No.5

N/A An integrated computer program consisting of a pre-processor, main solver, and post-processor was developed for the design of large steel castings. The pre-processor, based on the AutoCAD, enables the user to produce approval drawings, casting design drawings and mesh diagrams in sequence using a personal computer. In the main solver, two numerical models were employed; one models the fluid flow during mold filling, and the other models the heat transfer and solidification. The post-processor can be used to present simulation results such as flow pattern, mold filling sequences, solidification times, temperature gradients and location of shrinkage defects by color graphics. In order to validate the applicability of the present integrated program, a series of experiments on simple-shaped steel castings were carried out. After the validation of the present model, it was applied to the casting design of the large steel anchor of an SC42 alloy. Various solidification parameters such as a temperature distribution and a solidification time in the casting and the mold were compared with those obtained experimentally. Simulated results predicting shrinkage defects were in good agreement with those obtained experimentally. It was found that the present method can be successfully applied to the quantitative casting design for complex-shaped large steel castings. (Received June 4, 1997)

위암의 연령에 따른 차이

김영재(Young Jae Kim),이영철(Young Chul Rhee),이만길(man Kill Lee),차호(Ho Cha),정영채(Young Chae Jung) 대한소화기학회 1987 대한소화기학회지 Vol.19 No.1

N/A Comparative analytic review on clinical, endoscopic and histopathological findings was done in 13 cases of young age (under 29), 446 cases of mid age (30~69) and 39 cases of old age (above 70) stomach cancer who were visited Department of Internal Medicine of Masan Koryo General Hospital from March 1981 to July 1985. The following results were obtained: The peak of age incidence was the 5th decade amounting to 36.8%. The ratio between male and female was 2.6:1. The main chief complaint of each group was epigastric pain and it was followed by epigastric fullness. The most patient had the duration of symptom from 3 months to 6 months. For old-age group, mid-age group, major site of lesion in the antrum, meanwhile body for young-age group. The most frequent type of gastric cancer was type III in each group by Borrmanns classification. For each group, adenocarcinoma was major cases in the view of histopathological findings, and incidence of well differentiated type adenocarcinoma were lower in young-age group than others.

Biomass 유래 퓨란계 단량체를 이용한 폴리에스터의 중합 및 특성 연구

정용석(Yong Seong Chung),이영철(Young Chul Lee),서강진(Kang Jin Seo),김명준(Myeong Jun Kim),정지혜(Ji Hea Jeong),노시태(Si Tae Noh) 한국고분자학회 2011 폴리머 Vol.35 No.6

바이오매스에서 유래된 2,5-dihydroxymethylfuran(DHMF)을 KMnO4 산화반응으로 furan-2,5- dicarboxylic acid(FDCA)를 합성하였다. 합성한 FDCA와 다이올류를 에스테르화 반응과 축중합 반응을 진행시 켜 폴리에스터를 중합하였다. 폴리에스터는 NMR을 통해 조성을 분석하였고 DSC와 TGA를 통해 열적특성을 분 석하였다. 합성된 폴리에스터의 고유점도는 0.78∼1.2 dL/g으로 상용화된 poly(ethylene terephthalate)(PET) 와 비슷하였다. 다이올의 길이가 증가할수록 Young`s modulus와 strength는 낮아지고 elongation-to-break는 높아지는 경향을 확인하였다. 합성한 poly(ethylene furandicarboxylate)(PEF)의 Young`s modulus는 3551 MPa, strength는 103 MPa로 상용화된 PET와 비슷하였다. Furan-2,5-dicarboxylic acid (FDCA) was synthesized by KMnO4 oxidation of 2,5-dihydroxymethylfuran( DHMF) derived from biomass. Polyesters were synthesized by esterification and polycondensation of FDCA with various diols(ethane-1,2-diol, propane-1,3-diol, butane-1,4-diol, hexane- 1,6-diol, decane-1,10-diol). The composition of polyesters was characterized by using 1H NMR. Thermal properties of the polyesters were characterized by DSC and TGA. Intrinsic viscosities(IV) of the polyesters were measured to be 0.78∼1.2 dL/g comparable with IV of commercial poly(ethylene terephthalate)(PET). As the chain lengths of diols increased, Young`s modulus and strength decreased and elongation-to-break generally increased. Young`s modulus and strength of the polyesters were measured to be 3551 MPa and 103 MPa, respectively, comparable with commercial PET.

개선된 조건 합 가산기를 이용한 $54{\times}54$-bit 곱셈기의 설계

이영철,송민규,Lee, Young-Chul,Song, Min-Kyu 대한전자공학회 2000 電子工學會論文誌-SD (Semiconductor and devices) Vol.37 No.1

개선된 조건 합 가산기를 이용한 저전력 고속 $54{\times}54$-bit 곱셈기를 설계했다. 지연시간을 감소시키기 위해, Booth's Encoder 없이 높은 압축 율을 갖는 압축기들과 Carry 발생블록을 분리시킨 108-bit 조건 합 가산기를 제안하였다. 또한, 지연시간과 전력소모를 최적화하기 위해 패스 트랜지스터로직을 사용한 설계기법을 제안하였다. 제안된 곱셈기는 기존 곱셈기구조에 비해 약 12%의 지연시간과 5%의 전력소모가 감소하였으며, 0.65${\mu}m$ CMOS(Single-poly, triple-metal)공정을 사용하여 $6.60{\times}6.69mm^2$의 칩 크기와 공급전압 3.3V에서 13.5ns의 지연시간을 갖는다. In this paper, a $54{\times}54$-bit multiplier based on a improved conditional sum adder is proposed. To reduce the multiplication time, high compression-rate compressors without Booth's Encoding, and a 108-bit conditional sum adder with separated carry generation block, are developed. Furthermore, a design technique based on pass-transistor logic is utilized for optimize the multiplication time and the power consumption by about 5% compared to that of conventional one. With $0.65{\mu}m$, single-poly, triple-metal CMOS process, its chip size is $6.60{\times}6.69\;mm^2$ and the multiplication time is 135.ns at a 3.3V power supply.

21세기 신 에너지 가스 하이드레이트 연구 및 기술개발 현황 : 국내의 중장기 개발 방향

이영철,백영순,조병학,박기환,류병재,Lee Young Chul,Baek Young Soon,Cho Byoung Hak,Park Ki Whan,Ru Byong Jae 한국석유지질학회 1999 한국석유지질학회지 Vol.7 No.1

에너지 자원의 빈국인 한국은 에너지 자원의 기본적인 사용량 중에서 절대적인 양을 차지하는 석유 및 천연가스를 $100{\%}$수입에 의존하고 있다. 정부가 유사시 즉각적으로 실시하여야 할 중요한 역할 중의 하나가 이와 같은 유용한 에너지 자원을 다양하게 확보하는 것이다. 가스 하이드레이트는 천연가스와 다론 형태의 에너지로서 그 매장량이 해양이나 영구동토지역 등 전세계적으로 분포되어 있으므로 가까운 미래의 천연가스 대체 자원으로서 주목을 받고 있다. 특히 한반도 주변의 동해에 많은 양의 가스 하이드레이트가 매장되어 있을 것으로 기대된다 따라서 이 논문에서는 국내외 연구 및 기술개발 동향을 검토하여 탄성파 탐사를 통한 해석, 가스 하이드레이트의 특성 및 물리적인 물성, 그리고 가스 하이드레이트의 활용 기술 등에 관련된 국내의 중장기적인 가스 하이드레이트의 기본적인 연구 및 기술개발에 대하여 전체적인 프로젝트의 개요를 설명하였다. Korea, an energy-resources-poor country, imports $100{\%}$ of its, oil and, natural gas supply, which accounts for the greater part of its total primary requirements. One of the important task of the government is diversification of available energy resources such as oil and natural gas. Natural gas hydrate, which is non-conventional types of natural gas, distributes worldwide, especially in marine and permafrost. It would become a target of natural gas resources in the near future. Especially sigrificant amount of hydrates are expected to be located in the East Sea around Korea Peninsular. This paper describes about a multi-year overall project framework of basic research and technological development of natural gas hydrate in Korea focused on the interpretation of the seismic survey, the characteristics and physical properties of the natural gas hydrate, and the utilizable technology of natural gas hydrates from the status of research and development of the world.

밀리미터파 SiP 응용을 위한 기생 공진 모드 억제

이영철,Lee Young-Chul 한국전자파학회 2006 한국전자파학회논문지 Vol.17 No.9

In this paper, parasitic resonance modes generated in a conductor backed coplanar wave guide(CBCPW) and stripline band pass filter(BPF) and the oscillation phenomena of a 40 GHz power amplifier module(PAM) are analyzed and several methods to suppress them are presented for low-temperature co-fired ceramic(LTCC) based millimeter-wave RF System-in-Package(SiP) applications. Parasitic rectangular wave guide(RWG) modes of the CBCPW structure are completely suppressed in the operation frequency band by decreasing the distance between its vias and by increasing the mode frequency. In the stripline structure, RWG resonance modes are clearly eliminated by removing some vias facing each other and by placing them diagonally. In the case of the 40 GHz PAM, in order to reduce a cross talk due to radiation that is generated from interconnection discontinuities, high isolation structures such as embedded DC bas lines and CPW signal lines are used and then the oscillated PAM is improved. 본 논문에서는 저온 소성 세라믹(Low-Temperature Co-fired Ceramic: LTCC)에 기초한 밀리미터파 RF SiP(System-in-Package) 모듈 응용을 위하여, CBCPW(Conductor Backed CPW) 전송선과 스트립 라인 대역 통과필터(BPF)에서 기생적으로 발생하는 공진 모드들과 40 GHz 전력 증폭기 모듈의 발진 현상을 분석하고 이를 제거하기 위한 방법들을 제안하였다. CBCPW 구조에서의 기생 구형 도파관(RWG) 모드는 비아의 간격을 줄여 공진 주파수를 높게 하여 동작 주파수 내에서 완전히 억제하였다. 스트립 라인 구조에서는 마주 보는 비아 중한 쪽을 제거하여 대각선으로 비아를 배치함으로써 완전히 제거하였다. CBCPW의 마이크로스트립 패치 공진기 모드들을 제거하기 위하여, 갭을 통한 커플링을 감소시키기 위해 갭에 인접하게 비아를 배치하였다. 그 결과 기생 공진 모드들이 완전히 제거되었다. 40 GHz 대역의 능동 증폭기 모듈의 경우, 상호 연결(interconnection)불연속 효과로 발생한 방사에 의한 인한 누설(cross talk)을 억제하기 위해, LTCC 기판 내부에 내장된 DC 전원 배선과 CPW 전송선의 고 격리 구조를 사용하여 발진 현상을 개선하였다.

반복 금형주조용 자동 금형냉각장치 개발 및 적용 1 : 용탕충진거동 및 응고해석

이영철,이상목,최정길,홍준표 ( Young Chul Lee,Sang Mok Lee,Jeong Kil Choi,Chun Pyo Hong ) 한국주조공학회 1998 한국주조공학회지 Vol.18 No.2

N/A A three dimensional simulation program based on the SOLA-VOF technique was developed for the modeling of mold filling and solidification sequences of the AC4B alloy in the cyclic permanent mold casting process. The geometries and mesh diagrams of the casting and the mold were automatically generated using a pre-processor based on the commercial Auto-CAD system. The solidification time of the casting and the temperature variation of the mold with cyclic casting were evaluated using the present scheme. The effects of the local water cooling of the metal mold on the cyclic casting process were also examined in order to control the temperature variation in the mold and to improve the soundness of the castings. The minimization of the casting cycle time was also confirmed by the present program for an improved productivity. It can be concluded that the present program can be used for obtaining the optimum casting parameters and the local cooling condition for obtaining sound castings without shrinkage defects in the cyclic mold casting process. (Received March 2, 1998)

초소형 60 GHz LTCC 전력 증폭기 모듈

이영철,Lee, Young-Chul 한국전자파학회 2006 한국전자파학회논문지 Vol.17 No.11

본 논문에서는 저온 소성 세라믹(LTCC)에 기초한 SiP 기술을 이용하여 60 GHz 무선 통신을 위한 송신기용 초소형 전력 증폭기 LTCC모듈을 설계 및 제작하여 그 특성을 측정하였다. 60 GHz대역에서 LTCC 다층 기판과 전력 증폭기 MMIC의 상호 연결 손실을 줄이기 위해 와이어 본드와 기판 사이의 천이를 최적화하였고, MMIC 집적을 위한 고 격리 구조를 제안하였다. 와이어 본드 천이의 경우, 와이어의 인덕턴스를 감소시키기 위해 매칭 회로의 설계와 와이어 상호간의 간격을 최적화하였다. 또한 상호 연결 불연속 효과로 인한 전계의 방사를 억제하기 위해 코프라나 와이어 본드 구조를 이용하였다. 고 격리 모듈 구조를 위하여, LTCC 기판 내부에 DC 전원 배선을 내장시키고 비아로 그 주위를 차폐를 시켰다. 5층의 LTCC 기판을 사용하여 제작된 전력 증폭기 LTCC모듈의 크기는 $4.6{\times}4.9{\times}0.5mm^3$이고, $60{\sim}65GHz$ 대역에서 이득과 P1dB 출력 전력은 각각 10 dB와 11 dBm이다. In this paper, using low-temperature co-fired ceramic(LTCC) based system-in-package(SiP) technology, a very compact power amplifier LTCC module was designed, fabricated, and then characterized for 60 GHz wireless transmitter applications. In order to reduce the interconnection loss between a LTCC board and power amplifier monolithic microwave integrated circuits(MMIC), bond-wire transitions were optimized and high-isolated module structure was proposed to integrate the power amplifier MMIC into LTCC board. In the case of wire-bonding transition, a matching circuit was designed on the LTCC substrate and interconnection space between wires was optimized in terms of their angle. In addition, the wire-bonding structure of coplanar waveguide type was used to reduce radiation of EM-fields due to interconnection discontinuity. For high-isolated module structure, DC bias lines were fully embedded into the LTCC substrate and shielded with vias. Using 5-layer LTCC dielectrics, the power amplifier LTCC module was fabricated and its size is $4.6{\times}4.9{\times}0.5mm^3$. The fabricated module shows the gain of 10 dB and the output power of 11 dBm at P1dB compression point from 60 to 65 GHz.

개량차분법에 의한 주강품 및 대형 잉곳드의 응고해석과 수축공 예측

이영철,김종원,홍준표 ( Young Chul Lee,Jong Won Kim,Chun Pyo Hong ) 한국주조공학회 1989 한국주조공학회지 Vol.9 No.1

N/A Solidification analysis was conducted on large steel castings and ingots by a modified finite difference method. Auto-mesh generation system was developed for improving the application of the computer analysis system to casting design. Combined use of the prediction parameters, solidification time and temperature gradient, and an auxiliary parameter, shrinkage potential, were used to predict the formation of shrinkage defects. Several examples on the prediction of shrinkage cavity by this method were compared with the experimental results. It was found that a quantitative design of large steel castings and ingots can be made by the computer aided analysis of solidification process.