페롭스카이트 촉매를 이용한 프로판의 오토써멀개질반응을 통한 수소 제조

이귀연,김영철,박남국,신재순 한국공업화학회 2005 응용화학 Vol.9 No.2

Production of hydrogen by autothermal reforming of propane over perovskite catalysts

이귀연,신재순,박남국,김영철 한국공업화학회 2005 한국공업화학회 연구논문 초록집 Vol.2005 No.1

청년교회봉사자의 번아웃 경험에 관한 단일사례연구: 기독교 상담적 제안

이귀연 한국복음주의상담학회 2022 복음과 상담 Vol.30 No.1

The purpose of this study is to consider preventive and therapeutic interventions on the Christian counseling perspective by understanding the factors that cause burnout of youth church volunteer and the development process of it. In order to understand the ‘how’ and ‘why’ burnout of youth church volunteer occurred and developed, the factors causing burnout and the development process of three main symptoms were analyzed and generalized. As a result of the study, the factors of it was classified into individual, organizational and sociocultural dimensions, and the main symptoms developed into 'reduced personal accomplishment'-'emotional exhaustion'-'depersonalization’. This was related to the participant's personal factors, the nature of faith and motives for volunteering, and the unique background of the Korean church, characteristics of Millennials, and social phenomena related to youth unemployment. Christian counseling was proposed in 'life, relationship, and self', and it was a practical experience of God's presence through Sabbath, restoration of the narrative of Christ through empathy of God, and restoration of the image of God from self-discord in one's life. 본 연구의 목적은 청년교회봉사자의 번아웃 경험을 이해함으로써 기독교 상담적 예방과 치유의 방향성을 제안하는데 있다. 본 연구는 ‘단일사례연구'(single case study)로 진행하였으며, 실천 현장에서 청년교회봉사자의 번아웃이 ‘어떻게’ 그리고 ‘왜’ 발생되고 발전되었는지 이해하기 위해서 요인과 요인간의 역동적인 관계를 살피고, 세 가지 주요 증상의 발달과정을 분석하여 일반화를 시도하였다. 연구결과, 청년교회봉사자의 번아웃을 유발하는 요인은 개인적 차원과 조직(교회)적 차원, 그리고 사회문화적인 차원으로 분류할 수 있었고, 번아웃의 주요 증상은 ‘개인적 성취감의 감소’-‘정서적 탈진’-‘비인간화’ 순으로 발달하는 것을 확인할 수 있었다. 이는 참여자의 인구통계적, 심리적 특성과 신앙의 본질과 봉사의 동기, 그리고 한국교회의 독특한 성장배경과 밀레니얼 세대의 특성 및 청년실업에 관한 사회적 현상과 관련했다. 기독교 상담적 제안은 ‘일상, 관계, 자아’의 영역에서 이루어졌으며, 일상의 중단(안식)을 통한 하나님 임재의 실천적 경험과 성육신적 공감을 통한 그리스도의 서사성 회복, 그리고 자아불일치로 부터의 하나님 형상의 회복이었다.

간암조직에서 DNA methyltransferase의 발현

이귀연,박혜정,심용희 建國大學校基礎科學硏究所 2002 理學論集 Vol.27 No.-

암억제유전자의 과메틸화는 유전자의 발현을 억제하는 작용으로 암발생 기전에 중요한 요인으로 알려져 왔다. DNA 과메틸화는 DNA methyltransferase (Dnmt)에 의해서 생성되는데 현재까지 그 기능이 알려진 것으로 Dnmt1, Dnmt3a, Dnmt3b가 있다. 본 논문에서는 한국인의 간암조직 27개과 각 예에 상응되는 정상조직 27 개에서 위의 세 효소의 발현정도를 역전사효소-중합연쇄반응으로 조사하였다. Dnmt1는 정상조직에서 40.7% (11/27), 간암조직에서 33.3% (9/27); Dnmt3a는 정상조직에서 22.2% (6/27), 간암조직에서 63% (17/27); Dnmt3b는 정상조직에서는 전혀 발현 되지 않았으며 간암조직에서 51.9% (14/27)가 발현되었다. Dnmt1은 유전자의 메틸화정도를 유지시키는 기능을 하는 반면에 Dnmt3a와 Dnmt3b는 de novo 메틸화를 담당한다. Dnmt3a와 Dnmt3b의 발현이 Dnmt1보다 1.6-1.9 배 간암조직에서 높았으며 정상조직에서는 Dnmt1 (40.7%)의 발현이 22.2%인 Dnmt3a와 전혀 발현을 보이지 않은 Dnmt3b보다 훨씬 높았다. 위의 실험결과는 정상조직에서는 유전자의 메틸화를 유지하기 위하여 DNA 메틸화가 되는 반면에 종양조직에서는 새로운 유전자의 메틸화가 유발됨을 시사한다. 이는 새로운 유전자의 과메틸화의 증가가 암 발생기전의 요인이 될 가능성을 제시하는 결과이다. Hypermethylation on CpG islands of a tumor suppressor gene has been frequently detected in a variety of cancer cells and known to repress the level of transcription. To identify the molecular mechanism for hypermethylation of tumor suppressor genes in hepatocellular carcinomas (HCC), we examined DNA methyltransferase (Dnmt) expression level in HCC. Three Dnmts, Dnmt1, Dnmt3a and Dnmt3b that have been identified as being enzymatically active were examined by RT-PCR. Expression of Dnmts was detected in both non-neoplastic control liver and in HCC. Eleven out of 27 (40.7%) controls and 9 out of 27 (33.3%) HCC; 6 out of 27 (22.2%) controls and 17 out of 27 (63%) HCC; none of 27 controls and 14 out of 27 (51.9%) HCC revealed expression of Dnmt1, Dnmt3a, and Dnmt3b, respectively. The relatively high frequency of Dnmt1 expression in non-neoplastic control suggests that expression of Dnmt1 is required for maintenance of methylation profile in non-neoplastic cells. In addition, higher frequencies of Dnmt3a and Dnmt3b expression in HCC suggest that de novo DNA methylation in tumor cells may be the major process for gene inactivation during hepatocarcinogenesis.

정지 상태의 CW CO₂원형 레이저 빔에 의한 실리콘의 온도 계산

이귀연,김봉열 연세대학교 산업기술연구소 1987 논문집 Vol.19 No.2

The nonlinear one-dimensional heat equation is solved using a finite-difference method during irradiation of ion-implanted silicon with a stationary CW CO₂laser. This calculation is based on a thermal melting model, taking into account the temperature-dependent thermal and optical properties of both the liquid and solid-thermal conductivity, specific heat capacity, reflectivity, and absorption coefficient. Results of calculations show that the surface temperature induced by a laser beam at room temperature can not be sufficient to recrystallization. However, in the case of the substrate heating 623。K and above, the surface temperature can be sufficient to recrystallization and the surface may be melted.

Bit-line 인가 전압 보정에 의한 다중 셀 낸드 플래시 메모리 CCI 에러 보정

이귀연(Kui-Yon Lee) 한국정보기술학회 2014 한국정보기술학회논문지 Vol.12 No.11

In this paper, we propose a new method which corrects the MLC NAND flash memory data error caused from CCI by adjusting the applied bit-line voltage. To verify the proposed method, the threshold voltage shift (ΔV<SUB>TH</SUB>) of a victim cell caused by three adjacent aggressor cells is analyzed and the cell string current is calculated in MLC NAND flash memory with 20nm design rule and 64 cell string gate architecture. The calculated data show that about 60mV of the threshold voltage (ΔV<SUB>TH</SUB>) could be corrected by adjusting 0.1V in the applied bit-line voltage. Therefore, when we read multiple cells simultaneously which share the same word line, we may correct CCI error without performance degradation by adjusting each applied bit-line voltage depending on CCI degree.

열처리 방법에 따른 이온 임프란테이션한 다결정 실리콘 박막의 결정구조 조사

이귀연,김봉열 연세대학교 산업기술연구소 1987 논문집 Vol.19 No.2

After the films of low pressure CVD silicon were deposited at 630℃ to a thickness of 5500Å on a 1000 Åthick layer of thermally grown SiO₂on a Si substrate, a conventional X-ray diffraction is used to measure the structural changes as they are produced by the ion implantation and annealing processes. As-deposited and implanted silicon layer exhibit the strong <110> preferred texture. The thermal annealing process of low dose implanted silicon layer decreases the relative intensity of <110> texture; the relative intensities of <111> and <311> textures increase, especially of the <111> texture more increasing. But this process of high dose implanted silicon layer increases <110>, <311>, and <111> textures. However, the rapid thermal annealing process of low dose implanted silicon layer decreases <110> and <311> textures; <111> texture increases slightly. This process of high dose implanted silicon layer increases all <110>, <311>, and <111> textures.

NAND Flash Memory의 Sensing Margin 개선

이귀연(KuiYon Lee) 한국정보기술학회 2006 한국정보기술학회논문지 Vol.4 No.6

The sensing margin has been improved by applying Vcc to source at the read mode. The improvement was 3 times as large as the conventional method. Two step amplification method was proposed to prevent some distortion of the program cell information. On the basis of this proposal, the distortion can be mitigated by a half.

HEV 운전 특성 분석을 통한 삼원촉매 시스템 개발

이귀연(Kwiyeon Lee),송진우(Jinwoo Song) 한국자동차공학회 2021 한국자동차공학회 학술대회 및 전시회 Vol.2021 No.11

TPMS용 저주파 수신기의 설계

이귀연(KuiYon Lee),윤종철(JongChel Yun) 한국정보기술학회 2008 한국정보기술학회논문지 Vol.6 No.2

In this paper, a low frequency receiver has been designed for TPMS application. A 0.35㎛ Si BiCMOS process library of the NEC is used in the design of the low frequency receiver. In order to verify the performance of the proposed receiver, a simulation study has been carried out. The simulation result showed that the designed receiver could be used as a low frequency receiver in the range of 0.05~0.45V input signal level at 10㎂. From the simulation result, we also verified that the designed receiver had the low power operational characteristics at 1.8V supply voltage.