치과용 세라믹스의 제조 및 특성 (Ⅰ)

고영호,한복섭,이준희 동아대학교 공과대학 부설 한국자원개발연구소 1993 硏究報告 Vol.17 No.2

It has been investigated the Sintering Characteristics and Microstructure after the Manufacture of Dental Ceramics for Artificial Dental Tooth(Dental Crowns) in Dentistry. The Manufacture of High Thermal Expansional Leucite Crystals has been made by not Conventional Melting Process, but Sol-Gel Process, and composited with Class Frit that has low melting point to get Transparent Sintering Materials. The Crystal Forming Temperature of Leucite manufactured by Sol-Gel Process has been observed after Heat Treatment at various Temperatures. In Addition, The Manufacture Process is simpler than Conventional Melting Process and could be able to manufacture at about 400℃ low Temperature. Glass Frit that has low melting point was fabricated with about 10~30㎛ homogeneous amorphous Powders by means of Ball Milling and was transparent When fired. The Sintering Temperature could be controlled in accordance with the Powder Mixture of Leucite and Glass Frit. The Volume Fraction of Leucite Crystals in Glass Matrix has been increased by the appropriate Heat Treatment of Dental Porcelain.

규소에 있어서 붕소의 확산에 대한 2차원적 수치해석 모델

고관영,송준호,윤석길 울산대학교 1992 공학연구논문집 Vol.23 No.2

본 연구에서는 불활성 분위기에서 규소에 대한 붕소의 예비석출과 주입에 대한 확산모델을 세워 수치해석법으로 최종 농도분포를 계산하였다. 확산계수의 모델로서는 공공기구를 사용하였으며, Fair모델을 사용하였다. 붕소의 표면농도는 내삽법에 의해 구하였다. 확산 방정식의 선형화 방법으로는 유한 차분법을 사용하였으며, 해법으로는 Stone의 SIP 방법을 적용했다. 시뮬레이션 결과와 실험치의 비교로부터 제시된 모델의 유효성을 확인하였다. In the present work, the final impurity distributions in silicon through boron diffusion processes in inert atmosphere were calculated using computer aided numerical analysis methods. The diffusion coefficients of substitutional impurities were modeled with vacancy mechanism. It is assumed that the boron diffusion is governed by Fair model. The surface concentration of boron was approximated by the interpolation. For the linearization of diffusion equation the finite difference method was utilized. For the linearization of diffusion equation the finite difference method was utilized. For the solution of the resulting simultaneous equations the strong implicit procedure by Stone was used. It is observed that the simulated results of boron diffusions have been well-fitted to the experimental results.

일부 남성 금속제품 조립작업자들의 피로에 영향을 미치는 작업관련요인

장준호,강동묵,고상백,김정원,조병만,이수일 大韓産業醫學會 2004 대한직업환경의학회지 Vol.16 No.2

목적 : 남성 금속제품 조립 작업자들의 피로에 영향을 미치는 작업관련요인을 파악하고자 한다. 방법 : 작업자의 일반적 특성 및 작업관련 특성, 육체적 부하, 직무 스트레스 등을 조사 항목으로 하여 자동차 부품 조립업 1개소(476명), 자동차 엔진 조립업 1개소(610명), 대형 선박 엔진 조립업 1개소(454명)의 작업자(1,540명)를 대상으로 수거된 설문지 중 부실하게 응답한 38부를 제외한 1,136부(총연구대상의 73.8%)를 분석하였고, 피로도와의 연관성을 다중선형회귀분석으로 살펴보았다. 조사는 자기 기입식 설문지를 사용하였다. 육체적 부하를 측정하기 위해서는 Borg의 scale이 사용되었다. 격무 스트레스를 측정하기 위해서는 Karasek의 Job content questionnaire가 사용되었다. 피로의 측정은 전반적 피로도(sum of fatigue), 일상생활 기능장애(daily dysfunctioning), 상황적 피로(situational fatigue), 피로점수의 총합(sum of fatigue)으로 구성되어 있는 다면적 피로척도를 사용하였다. 피로점수의 분포는 본 연구에 응답한 피로점수의 총합을 사분위수로 나누어서 4등급으로 나누었다. 결과 : 피로점수의 분포는 피로점수의 총합을 사분위수로 나누었을 때, 0≤1등급≤73, 74≤2등급≤82, 83≤3등급≤93, 94≤4등급≤133이었다. 다중선형회귀분석에서 피로점수의 총합과 유의한 관계를 보인 경우는 주간근무, 긴 주당 노동시간, 높은 육체적 부하, 높은 직무요구도, 낮은 직무자율성, 낮은 상사의 지지 등이었고, 전반적 피로도와 유의한 관계를 보인 경우는 주간근무, 높은 육체적 부하, 높은 직무요구도, 낮은 직무자율성, 낮은 상사의 지지 등이었다. 일상생활 기능장애와 유의한 관계를 보인 경우는 주간근무, 긴 주당 노동시간, 높은 육체적 부하, 낮은 직무자율성 등이었다. 상황적 피로와 유의한 관계를 보인 경우는 높은 연령, 주간근무, 긴 주당 노동시간, 낮은 직무자율성 등이었다. 결론 : 피로관련 요인은 긴 주당노동시간, 높은 직무요구도, 높은 육체적 부하, 낮은 직무자율성, 낮은 상사의 지지로 생각된다. Objectives: To find work related factors affecting perceived fatigue among male metal product assemblers. Methods: The study subjects were metal product assemblers from three metal product companies (476 car parts assemblers, 610 car engine assemblers, 454 ship engine assemblers). From the total of 1,540 subjects, 1,136 (73.8%) were included and 38 respondents with insufficient replies were excluded. Associations between fatigue score and other variables (general characteristics, job related factors, workload, job stresses) were investigated in terms of the concept of multidimensional fatigue construct by self administered questionnaire. Using MFS (Multidimensional Fatigue Scale), JCQ (Job Content Questionnaire), and Borg's scale, we estimated the fatigue, job stress, and workload, respectively. Fatigue score was estimated by 'sum of fatigue' in MFS. Associations were tested by linear regression analysis using SAS v.8.0. Results: In this study, the fatigue related factors were older age, longer working hours per week, higher workload, higher job demand, lower decision latitude, and lower supervisor support. Conclusions: Prolonged working hours, higher workload, higher job demand, poor supervisor support and lower decision latitude were fatigue related factors among the male metal product assemblers of this study.

한국인 직무 스트레스 측정도구의 개발 및 표준화

장세진,고상백,강동묵,김성아,강명근,이철갑,정진주,조정진,손미아,채창호,김정원,김정일,김형수,노상철,박재범,우종민,김수영,김정연,하미나,박정선,이경용,김형렬,공정옥,김인아,김정수,박준호,현숙정,손동국 大韓産業醫學會 2005 대한직업환경의학회지 Vol.17 No.4

Background and Purposes: Over the past three decades, numerous studies performed in Korea have reported that job stress is a determinant risk factor for chronic diseases and work disability. Every society has its own culture and occupational climate particular to their organizations, and hence experiences different occupational stress. An occupational stress measurement tool therefore needs to be developed to estimate it objectively. The purpose of this study is to develop and standardize the Korean Occupational Stress Scale (KOSS) which is considered to be unique and specific occupational stressors in Korean employees. Subjects and Methods: Data were obtained from the National Study for Development and Standardization of Occupational Stress (NSDSOS Project: 2002-2004). A total of 12,631 employees from a nationwide sample proportional to the Korean Standard Industrial Classification and the Korean Standard Occupational Classification were administered. The KOSS was developed for 2 years (2002-2004). In the first year, we collected 255 items from the most popular job stress measurement tools such as JCQ, ERI, NIOSH and OSI, and 44 items derived from the a qualitative study (depth interview). Forty-three items of KOSS, in the second year, were retained for use in the final version of the KOSS by using Delphi and factor analysis. Items were scored using conventional 1-2-3-4 Likert scores for the response categories. Results: We developed eight subscales by using factor analysis and validation process: physical environment (3 items), job demand (8 items), insufficient job control (5 items), interpersonal conflict (4 items), job insecurity (6 items), organizational system (7 items), lack of reward (6 items), and occupational climate (4 items). Together they explained 50.0% of total variance. Internal consistency alpha scores were ranged from 0.51 to 0.82. Twenty-four items of the short form of the KOSS (KOSS-SF) were also developed to estimate job stress in the work setting. Because the levels of the subscales of occupational stress were gender dependent, gender-specific standard norms for both the 43-item full version and the 24-item short form using a quartile for the subscales of KOSS were presented. Conclusion: The results of this study suggest that KOSS might be an appropriate measurement scale to estimate occupational stress of Korean employees. Further and more detailed study needs to be conducted to improve the validity of this scale.

사무직 근로자들의 직무 스트레스와 피로

차경태,김일희,고상백,현숙정,박준호,박종구,차봉석,장세진 大韓産業醫學會 2008 대한직업환경의학회지 Vol.20 No.3

목적: 이 연구는 전국 규모의 조사 연구에서 수집된 자료 중 사무직 근로자들을 대상으로,사회인구학적 특성,직업 특성,건강행태,직무 스트레스와 피로수준 간의 관련성을 분석하는 데 있다. 방법:‘한국인 직무스트레스 측정도구의 표준화 전국 조사연구National Study for Development and Standardization of Occupational Stress (NSDSOS Project: 2002∼2004)’를 위해 2002년 5월 1일부터 2003년 5윌 30일 까지 수행되었으며,전국의 사업장에 근무하는 근로자 30,146명(남자: 84%,여자: 16%) 중 사무직 근로자 4,457명(남자: 68.9%,여자 31.1%)을 연구 대상으로 하였다. 자료수집방법은 사업장을 방문하여 보건 및 안전관리자 등에게 연구의 취지를 알린 후 설문조사에 대한 협조를 구하고 응답자 직접 기입법을 이용 하였으며,사회인구학적 특성,직업적 특성,건강관련 요인,KOSS-SF를 이용한 7개의 직무 스트레스 요인,그리고 MFS를 이용하여 피로 수준에 영향을 주는 요인에 대해 분석하였다. 결과: 일반적 특성,작업관련 특성,건강행태관련 특성 및 직무 스트레스 요인이 근로자들의 피로와 강한 관련성이 있음이 입증되었으며,특히 직무 스트레스의 하부 요인 중에서도 피로와 관련성을 보이는 요인이 남녀별로 다소 상이 하게 관련된다는 것을 발견할 수 있었다. 남자의 경우는 직무 스트레스의 하부 영역 중 직무 요구도,직무 불안정성,보상부적절 등이 영향력이 높은 주요 직무 스트레스 요인이었던 반면,여자는 직무 요구도,보상부적절,직장문화가 주요한 직무 스트레스 요인이었다. 결론: 직장인 피로가 갖는 보건학적 의학적 경제학적 중요성을 감안할 때,조직의 생산성 향상과 근로자 개개인의 삶의 질 향상 및 건강증진을 위해선 직무 스트레스 관리 프로그램이 절실히 요청된다고 볼 수 있다. Background & Objectives: A growing body of research has documented that occupational stress is closely associated with increased risk of fatigue. This study was conducted in an effort to assess the relationship of occupational stress to self-perceived fatigue among Korean white collar employees. Methods: Data were obtained from the National Study for Development and Standardization of Occupational Stress (NSDSOS Project, 2002-2004). Among them, a total of 4,502 white collar employees were recruited. A structured questionnaire was employed to evaluate the participants' sociodemographics, job-related factors, health-related behaviors, occupational stress, and self-perceived fatigue. Occupational stress and self-perceived fatigue were assessed using the Korean Occupational Stress ScaleShort form (KOSS-SF) and the Multidimensional Fatigue Scale (MFS), respectively. Results: In logistic regression analyses, occupational stress was associated with an increased risk of fatigue, and some domains of occupational stress had different effects on fatigue by gender (job demand, job insecurity, and lack of reward for men, job demand, lack of reward, and discomfort in occupational climate for women), which indicates that occupational stress may perform a slightly different role in increasing the risk of fatigue by gender. Conclusion: The results of this study suggest that occupational stress is a determinant predictor of self-perceived fatigue. Thus, a stress management program for the reduction of occupational stress, and the promotion of white collar worker's health and quality of life is strongly recommended. Some limitations of this study and considerations for future studies were also discussed.

관동맥 스텐트 삽입후 발생한 스텐트 변연부 박리의 예측인자 및 추가적 치료후 임상적 의의에 관한 연구 : Predictor, Angiographic and Clinical Follow-up after Additional Procedures

두영철,박수종,김재삼,이준호,홍경순,박대균,한규록,오동진,유규형,임종윤,고영박,이광학,이영 대한순환기학회 1998 Korean Circulation Journal Vol.28 No.11

Stromal Vascular Fraction From Adipose Tissue Forms Profound Vascular Network Through the Dynamic Reassembly of Blood Endothelial Cells

Koh, Young Jun,Koh, Bong Ihn,Kim, Honsoul,Joo, Hyung Joon,Jin, Ho Kyoung,Jeon, Jongwook,Choi, Chulhee,Lee, Dong Hun,Chung, Jin Ho,Cho, Chung-Hyun,Park, Won Seok,Ryu, Ji-Kan,Suh, Jun Kyu,Koh, Gou Young Ovid Technologies Wolters Kluwer -American Heart A 2011 Arteriosclerosis, thrombosis, and vascular biology Vol.31 No.5

Multicenter retrospective analysis of patients with chronic lymphocytic leukemia in Korea

Jun Ho Yi,이경원,이지현,Kwai Han Yoo,Chul Won Jung,Dae Sik Kim,Jeong-Ok Lee,Hyeon Seok Eom,Ja Min Byun,Youngil Koh,Sung Soo Yoon,Jin Seok Kim,Jee Hyun Kong,Ho-Young Yhim,Deok Hwan Yang,Dok Hyun Yoon,Do Hyou 대한혈액학회 2021 Blood Research Vol.56 No.4

Background Chronic lymphocytic leukemia (CLL) is the most common type of adult leukemia in Western countries but is rare in the East Asian countries. Due to its rarity and the lack of feasible novel agents and laboratory prognostic tools, there are limited data on the clinical outcomes of this disease in Asia. To clarify the current treatment status, we performed a multicenter retrospective analysis of patients with CLL in Korea. Methods The medical records of 192 eligible patients between 2008 and 2019 were reviewed for clinical characteristics, treatment courses, and outcomes. The first-line treatment regimens of the patients included in this analysis were as follows: fludarabine/cyclophosphamide/ rituximab (FCR) (N=117, 52.7%), obinutuzumab plus chlorambucil (GC) (N=30, 13.5%), and chlorambucil monotherapy (N=24, 10.8%). Results The median progression-free survival (PFS) was 55.6 months, and the average 2-year PFS rate was 80.3%. PFS was not significantly different between the patients receiving FCR and those receiving GC; however, chlorambucil treatment was associated with significantly inferior PFS (P <0.001). The median overall survival was 136.3 months, and the average 5- and 10-year OS rates were 82.0% and 57.4%, respectively. Conclusion This is one of the largest studies involving Korean patients with CLL. Although the patients had been treated with less favored treatment regimens, the outcomes were not different from those reported in Western studies.

돈분액비 시용이 토양화학성과 유채생육에 미치는 영향

강호준(Ho-Jun Kang),양상호(Sang-Ho Yang),이신찬(Shin-Chan Lee),이상순(Sang-Soon Lee),고성준(Seong-Jun Koh) 한국토양비료학회 2010 한국토양비료학회 학술발표회 초록집 Vol.2010 No.5

무향실을 이용한 철도용 간섭형 방음장치 성능평가에 관한 연구

조준호(Jun-Ho Cho),고효인(Hyo-In Koh),노희민(Hee-Min Noh),김호진(Ho-Jin Kim) 한국소음진동공학회 2011 한국소음진동공학회 학술대회논문집 Vol.2011 No.4