원자층 증착법으로 성장한 HfO₂ 박막의 제조

김희철,김민완,김형수,김혁종,손우근,정봉교,김석환,이상우,최병호,Kim Hie-Chul,Kim Min-Wan,Kim Hyung-Su,Kim Hyug-Jong,Sohn Woo-Keun,Jeong Bong-Kyo,Kim Suk-Whan,Lee Sang-Woo,Choi Byung-Ho 한국재료학회 2005 한국재료학회지 Vol.15 No.4

The growth of hafnium oxide thin films by atomic layer deposition was investigated in the temperature range of $175-350^{\circ}C$ using $Hf[N(CH_3)_2]_4\;and\;O_2$ as precursors. A self-limiting growth of $0.6\AA/cycle$ was achieved at the substrate temperature of $240-280^{\circ}C$. The films were amorphous and very smooth (0.76-0.80 nm) as examined by X-ray diffractometer and atomic force microscopy, respectively. X-ray photoelectron spectroscopy analysis showed that the films grown at $300^{\circ}C$ was almost stoichiometric. Electrical measurements performed on $MoW/HfO_2$(20 nm)/Si MOS structures exhibited high dielectric constant$(\~17)$ and a remarkably low leakage current density of at an applied field of $1.5-6.2\times10^{-7}A/cm^2$ MV/cm, probably due to the stoichiometry of the films.

산발성 위암에서 Microsatellite Instability 빈도와 hMLH1 촉진자부위 메칠화

김희철,노선애,육정환,오성태,김병식,유창식,김진천,Kim Hee Cheol,Roh Sun Ae,Yook Jeong Hwan,Oh Sung Tae,Kim Byung Sik,Yu Chang Sik,Kim Jin Cheon 대한위암학회 2003 대한위암학회지 Vol.3 No.1

Background: An aberrant function of the mismatch repair system has been reported to underlie carcinogenesis in several tumors, including colorectal and gastric carcinomas, and to induce the typical genotype of microsatellite instability (MSI). Purpose: We aimed to determine the frequency of MSI in early-onset sporadic gastric carcinoma and elucidate the role of promoter methylation in hMLH1 as the mechanism of MSI. Materials and Methods: Thirty-six early-onset sporadic gastric carcinomas were analyzed to determine the status of MSI and the frequency of methylation of the promoter region in hMLH1. MSI was determined using five markers recommended by NCI: MSI-H (high), MSI-L (low), and MSS (Microsatellite stable). Methylation specific PCR (MSP) and direct automated genomic sequencing analysis with DNA modified by sodium bisulfite have been performed to confirm promoter region methylation. All the data were analyzed regarding characteristics of molecular changes, and clinicopathologic variables. Results: The microsatellite status was determined as MSI-H in five cases ($13.8\%$), MSI-L in 13 cases ($36.1\%$), and MSS in 18 cases ($50.0\%$). hMLH1 was methylated in seven cases ($19.4\%$). In all cases of MSI-H, promoter of hMLH1 was methylated, and in two of the 13 cases of MSI-L, hMLH1 promoter methylation was identified. Methylation was not found in any cases of MSS. Promoter methylation in hMLH1 was significantly correlated with MSI status (P<0.001). We could not find any relationship between MSI and clinicopathologic parameters. Conclusion: These results suggest that an abnormal function of the mismatch repair system may be associated with gastric carcinogenesis in more than $10\%$ of early-onset gastric carcinomas and MSI appeared to be closely related to the promoter methylation in hMLH1.

그라우팅 자동관리 시스템(AGS)을 이용한 동홍천-양양 고속도로 14공구 저토피구간 강관보강그라우팅 시공사례

김희철,장기영,김진춘,이왕준,김병용,Kim, Hui-Cheol,Jang, Gi-Yeong,Kim, Jin-Chun,Lee, Wang-Jun,Kim, Byeong-Yong 한국지반공학회 2011 지반 : 한국지반공학회지 Vol.27 No.3

국내 최장대 도로터널(인제터널)의 시멘트광물계 급결제 적용사례

김희철,김대형,조남섭,김관일,Kim, Hui-Cheol,Kim, Dae-Hyeong,Jo, Nam-Seop,Kim, Gwan-Il 한국터널지하공간학회 2011 자연, 터널 그리고 지하공간 Vol.13 No.6

Bell's Palsy와 Ramsay Hunt Syndrome 환자군의 치료 기간에 따른 호전도의 비교 연구

김희철,김정호,김영일,Kim, Hee-Chul,Kim, Jeong-Ho,Kim, Young-Il 대한침구의학회 2008 대한침구의학회지 Vol.25 No.4

Objectives : The aim of this study is comparing the improvement of Bell's palsy and Ramsay hunt syndrome according to treatment duration. Methods : The 11cases diagnosed as Ramsay hunt syndrome and 30cases of Bell's palsy who visited Cheong-ju Oriental Medical hospital from February 2006 to June 2008 were evaluated. We used Yanagihara's unweighted Grading System to confirm the improvement. Results : In the analysis of cause, except the "none", the most common cause was "Overwork" in both two group. After 5-day treatment the score was getting worse but after 10-day treatment score was improved in both group. The improvement of Bell's palsy group was better than that of Ramsay hunt syndrome group after 5-day and 10-day treatment, but there was no significance. Conclusions : In comparison of Yanagihara's unweighted grading score checked before treatment, after 5-day, 10-day and 15-day treatment between Bell's palsy and Ramsay hunt sundrome, there was no statistical significant difference.

심부전(心不全)에의한 흉막삼출증(胸膜渗出症)으로 의심되는 환자(患者) 1례(例)에 대(對)한 임상적(臨床的) 고찰(考察)

김희철,이강녕,이동준,이영수,임진훈,이용운,김일렬,최창원,Kim, Hee-Chul,Lee, Kang-Nyung,Lee, Dong-Joon,Lee, Young-Soo,Lim, Jin-Hoon,Lee, Young-Yoon,Kim, Il-Ryul,Choi, Chang-Won 대한한방내과학회 2000 大韓韓方內科學會誌 Vol.21 No.4

Pleural effusion is a state, retention of a mount of liquid in pleural cavity. Main causes of pleural effusion is Congestive Heart Failure that is caused by left ventricular heart failure. And that of Congestive heart failure is caused by increase of pleural capillary pressure or remain of effusion in pleural cavity. Bilateral venous pressure of pleura make worse pleural effusion and one way of venous pressure of that bring out pleural effusion. The purpose of this study is to examine the efficacy of oriental treatment for pleural effusion is caused by heart failure. One woman of 86 years old complained the symptom of general weakness, dyspnea, flank pain, anorexia, insomnia, coughing, secretion mixed blood. The symptom is caused by effusion that is brought out acute pneumonia, heart failure. At the time of Admission, in the diagnosis of Admission, in the diagnosis of Hyuneum(懸飮) she had taken Kungha-tang hap pleurisy-bang,(芎夏湯合助膜炎方), so improved dyspnea, flank pain, insomnia, coughing. In views of examination, decrease of heart failure' s symptom and pleural effusion. After 13days of admission, she had taken palmul-tang.(八物湯). As a conseguence of that, the symptom of general weakness. anorexia is improved and she was discharged.

Kappa(2) 커버리지 함수를 이용한 ENHPP 소프트웨어 신뢰성장모형에 관한 연구

김희철,Kim, Hee-Cheul 한국정보통신학회 2007 한국정보통신학회논문지 Vol.11 No.12

유한고장수를 가진 비동질적인 포아송 과정에 기초한 모형들에서 잔존 오류 1개당 고장 발생률은 일반적으로 상수, 혹은 단조증가 및 단조 감소 추세를 가지고 있다. 소프트웨어 제품의 정확한 인도시기를 예측하거나 효용성 및 신뢰성을 예측하기 위해서는 소프트웨어 테스팅 과정에서 중요한 요소인 테스트 커버리지를 이용하면 보다 효율적인 테스팅 작업을 할 수 있다. 이런 모형을 ENHPP모형이라고 한다. 본 논문에서는 기존의 소프트웨어 신뢰성 모형인 지수 커버리지 모형과 S-커버리지 모형을 재조명하고 이 분야에 적용될 수 있는 Kappa 분포를 이용한 모형인 Kappa 커버리지 모형을 제안하였다. 고장 간격시간으로 구성된 자료를 이용한 모수추정 방법은 최우추정법과 일반적인 수치해석 방법인 이분법을 사용하여 모수 추정을 실시하고 효율적인 모형 선택은 편차자승합(SSE) 및 콜모고로프 거리를 적용하여 모형들에 대한 효율적인 모형 선택도 시도 하였다. 수치적인 예에서는 실제 고장자료를 통하여 분석하였다 이 자료들에서 기존의 모형과 Kappa 커버리지 모형의 비교를 위하여 산술적 및 라플라스 검정, 편의 검정 등을 이용하였다. Finite failure NHPP models presented in the literature exhibit either constant, monotonic increasing or monotonic decreasing failure occurrence rates per fault. Accurate predictions of software release times, and estimation of the reliability and availability of a software product require Release times of a critical element of the software testing process : test coverage. This model called Enhanced non-homogeneous Poission process(ENHPP). In this paper, exponential coverage and S-shaped model was reviewed, proposes the Kappa coverage model, which make out efficiency application for software reliability. Algorithm to estimate the parameters used to maximum likelihood estimator and bisection method, model selection based on SSE statistics and Kolmogorov distance, for the sake of efficient model, was employed. Numerical examples using real data set for the sake of proposing Kappa coverage model was employed. This analysis of failure data compared with the Kappaa coverage model and the existing model(using arithmetic and Laplace trend tests, bias tests) is presented.

한국인 정신분열병 환자에서 항정신병 약물의 치료 반응과 도파민 D2, D3 및 D4 수용체 유전자 다형성

김희철,정성원,김대광,정철호,Kim, Hee-Cheol,Jung, Sung-Won,Kim, Dae-Kwang,Jung, Chul-Ho 대한생물정신의학회 2007 생물정신의학 Vol.14 No.3

항정신병 약물의 치료 반응을 예측해 줄 수 있는 유전자 지표를 찾기 위한 최근의 많은 약물유전학 연구들은 일관된 결과를 보고하지 못하고 있다. 본 연구는 항정신병 약물의 치료 반응과 도파민 D2, D3 및 D4 수용체 유전자 다형성과 관련성을 조사하였다. 연구 대상은 18~60세에 해당되면서 정신분열병의 DSM-IV 진단기준을 만족하고 본 연구에 대해 서면 동의한 국립부곡병원의 입원 환자 200명이었다. 연구는 대상자들의 입원 당시 병록지를 검토하여 후향적으로 이루어졌다. 대상자들은 퇴원할 당시를 기준으로 약물치료 반응 정도에 따라'반응군'과'비반응군'으로 구분되었으며 양군 사이의 도파민 수용체 유전자 다형성 차이를 비교하였다. 대상자 200명 중에서 188명(94%)이 비전형 항정신병 약물을 사용하였고 반응군은 141명(70.5%)이었다. 도파민 D2 수용체 유전자 Ser311Cys 다형성, 도파민 D3 수용체 유전자 Ser9Gly 다형성, 도파민 D4 수용체 유전자 exon III의 48개 염기반복 다형성에서 반응군과 비반응군 사이의 대립유전자 및 유전자형 빈도의 차이를 보이지 않았다. 결론적으로 본 연구에서는 항정신병 약물의 치료 반응과 도파민 D2 수용체 유전자 Ser311Cys 다형성, 도파민 D3 수용체 유전자 Ser9Gly 다형성, 그리고 도파민 D4 수용체 유전자 exon III의 48개 염기반복 다형 성과는 연관성이 없었다. 향후에는 단일의 항정신병 약물에 대한 전향적인 방법의 통제된 연구가 필요하다. Objectives:A considerable number of pharmacogenetic studies have been performed in recent years to define the association of antipsychotic drug response with dopamine receptor polymorphisms. The purpose of this study was to investigate the relationship between the therapeutic response to antipsychotic drugs and the polymorphisms of the dopamine D2, D3, and D4 receptor genes(DRD2, DRD3 and DRD4, respectively). Methods:We conducted retrospective chart review of 200 consecutively hospitalized patients with the diagnosis of schizophrenia(DSM-IV) who were treated with various antipsychotics(94% atypical antipsychotics) at Bugok National Hospital, Korea. The patients were divided into two groups, responders and non-responders, by responsiveness to antipsychotic drugs according to a four-point scale used in previous studies; responders included moderate to marked responded patients and non-responders included none to minimal responded patients. We analyzed the Ser311Cys polymorphism in the DRD2, the Ser9Gly polymorphism in the DRD3, and the exon III 48 bp repeat polymorphism in the DRD4. Results:Among the total patients of 200, 141(70.5%) were categorized as responders. There were no significant differences in the frequencies of the DRD2, DRD3, and DRD4 alleles and genotypes between responders and non-responders. Conclusion:These results suggest that the Ser311Cys polymorphism in the DRD2, the Ser9Gly polym- orphism in the DRD3, and the exon III 48bp repeat polymorphism in the DRD4 are not associated with the therapeutic response to antipsychotic drugs in Korean schizophrenic patients. A larger prospective study is needed to elucidate the association between antipsychotic response and dopamine receptor gene polymorphism.

파레토 및 어랑 형상모수에 의존한 수명분포를 따르는 소프트웨어 신뢰성 모형에 대한 신뢰도 특성요인 비교 연구

김희철,문송철,Kim, Hee Cheul,Moon, Song Chul 한국데이터전략학회 2017 Journal of information technology applications & m Vol.24 No.2

Software reliability is one of the most elementary and important problems in software development In order to find the software failure occurrence, the instantaneous failure rate function in the Poisson process can have a constant, incremental or decreasing tendency independently of the failure time. In this study, we compared the reliability performance of the software reliability model using the parameters of Pareto life distribution with the intensity decreasing pattern and the shape parameter of Erlang life distribution with the intensity increasing and decreasing pattern in the software product testing. In order to identify the software failure environment, the parametric estimation was applied to the maximum likelihood estimation method. Therefore, in this paper, we compare and evaluate software reliability by applying software failure time data. The reliability of the Erlang and Pareto life models is shown to be higher than that of the Pareto lifetime distribution model when the shape parameter is higher and the Erlang model is more reliable when the shape parameter is higher. Through this study, the software design department will be able to help the software design by applying various life distribution and shape parameters, and providing basic knowledge using software failure analysis.

신문고-포장, 물류, 유통 분야와 RFID

김희철,Kim, Hui-Cheol (사)한국포장협회 2007 包裝界 Vol.167 No.-