에멀젼型 液膜에 對한 數式모델 比較硏究

宋東益,崔相俊 慶北大學校 1983 論文集 Vol.36 No.-

Two diffusion-controlled mathematical models for emulsion-type liquid membrane, which were proposed by Lightfoot and Ho, and Ihm and Choi, were simulated by solving numerically the coupled moving boundary value problem using Crank-Nicholson implicit method and were compared with the batch experimental data obtained previously for removal of phenol from waste water. The results have shown that Lightfoot and Ho's model which was based on uniform mass transfer resistance inside the emulsion globules was not in good agreement with the experimental data especially at initial time period, but Ihm and Choi's model considering mass transfer resistances in the outer liquid membrane layer and in the inner reacted zone simulataneously, was fitted well the experimental data for nearly entire time period. Therefor, Ihm and Choi's model taking into consideration the outer mass transfer resistance layer of liquid membrane was thought to be more predictive and more precise than Lightfoot and Ho's one in the emulsion-type liquid membrane.

하청 근로자들의 건강수준 평가

최홍열,고상백,장세진,차봉석,임형준,이상윤,김재용,강동묵,조수헌 大韓産業醫學會 2001 대한직업환경의학회지 Vol.13 No.1

목 적 : 하청노동을 이용한 노동 유연화 전략은 근로자들의 고용을 불안정시키고, 근로자들의 삶에 부정적 영향을 미치고 있다. 따라서 이 연구는 하청업체 근로자들의 고용현황을 조사하고, 기존의 업체중심의 건강평가의 문제점을 지적하고자 하였다. 또한 하청업체 근로자들의 건강평가의 현재적 의미와 사회적 배제의 특성을 알아보고자 하였다. 방 법 : 모기업과 하청업체 근로자들의 건강수준을 비교하기 위하여, 정기건강진단(일반, 특수)과 채용건강진단 자료를 이용하고자 하였다. 건강진단에서 누락된 비정규직을 포괄하기 위하여 SF-36을 이용하여 건강설문조사를 시행하였다.결 과 : 조선업 하청업체 근로자들의 고용기간은 짧고, 빈번한 노동이동 현상을 보였다. 3년간 건강진단 수검 현황을 통해 살펴볼 때, 1998년 수검자중 2000년까지 연속해서 검진 받은 수검자는 40.3%였다. 건강진단 결과 유소견자 규모를 통해 모기업과 하청업체간의 건강수준을 비교해 보았다. 모기업은 일반질병 요관찰자와 질병자를 포함한 유소견자가 1,011명으로 약 10 %의 유소견율을 보이고 있고, 질병자의 경우 596명으로 유병률이 5 %를 상회하고 있다. 반면 하청업체의 경우 1,967명의 수검자중 유소견자가 115명으로 6 %의 유소견율을 보이고있고, 질병자는 82명으로 4 %의 유병률을 보이고있다 채용건강진단을 받은 수검자는 6,260명 이었으며, 이 중 유소견자 수는 2,373명으로 전체 수검자의 37.9 %를 차지하였다. 건강설문지의 경우는 전체 건강수준의 총합은 하청보다 원청 근로자가 높았고 통계적으로 유의하였다. 결 론' 정기건강검진 결과는 하청근로자들이 고용형태에 따라 검진을 받지 못한 경우가 많아, 건강 근로자 효과로 표현될 가능성이 있다. 따라서 채용건강진단 결과는 다른 측면에서 하청업체 근로자들의 건강수준의 현실적 반영이라고 할 수 있다. 향후 하청업체 근로자들의 건강문제를 감시하고 개선하려면 기존의 업체 중심의 접근으로는 하청 근로자의 건강문제를 제대로 다룰 수 없고, 업종과 지역을 동시에 고려하여 접근할 필요가 있다. 또한 단기 고용 근로자 및 비정규직 근로자를 사회보장의 확충과 모기업의 연대책임 강화 및 기업복지 차원에서 포괄하는 방안이 모색되어야 하겠다. Objectives : The strategy for the labor flexibility through subcontracted labor have brought a negative effect on the lives of the workers, such as the increase of the unstable employment. This study was conducted to analyze the relationship between the employment of subcontracted firms and the health status of them, and to find out some problems which have been caused in the process of health evaluation and the characteristics of social exclusion. Methods : We reviewed the periodical health examination and preemployment health examination in order to compare health status of the subcontracted workers with those of the parent firm workers. The SF-36 questionnaire was administered to assess the self-perceived health status. Results : The result shows that compared to the working duration of the parent firm workers, those of the subcontracted workers were shorter, and the job transfer rate was higher. In the periodical health examination, the prevalence of occupational and general disease was higher in the parent firm(10%) than in the subcontracted firms(6%). Preemployment health examination plays an important role in worker's health manage- ment. Among 6,260 workers who received preemployment health examination, the prevalence of disease was 37.9%. Mean scores of health status measured by SF-36 were lower in the subcontracted firm than in the parent firm. Conclusions : Due to social exclusion of the subcontracted workers from the periodical health examination, there is a possibility that the periodical health examination have the healthy worker effect. These results suggests that the preemployment health examination could be a more appropriate indicator which is able to assess the health status of the subcontracted workers than the periodical health examination.

Mori 체계의 이해

崔尙惇,金泰縣,安琮準,李相錫,崔昌鎬 경북대학교 과학교육연구소 1989 科學敎育硏究誌 Vol.13 No.-

Heuristic understanding of Mori's problem is introduced

고양이 위 평활근 수축에 대한 Vanadate와 Pervanadate의 효과

심상수,최효봉,심혜선,이덕주,윤신희,한상준,김명석,조양혁 大韓消化器病學會 1999 大韓消化器病學會誌 Vol.33 No.1

液膜法에 依한 Cu(Ⅱ) 이온의 抽出에 關한 硏究

崔相俊,宋東益 慶北大學校 1984 論文集 Vol.37 No.-

Water in oil (W/O) emulsion was prepared from aqueous hydrochloric acid solution and xylene containing both benzoyl acetone as a carrier and Span 80 as a surfactant. After dispersing W/O emulsion into a third aqueous phase, external buffer solution dissolving copper ion, water in oil in water (W/O/W) emulsion was manufactured. Copper ion extraction was performed using this W/O/W emulsion system. Effects of characteristic of external aqueous solution on emulsion stability were investigated and optimum extraction conditions were determined using the results of extraction experiment. Optimum conditions were as follows; surfactant concentration was 2wt. %, internal aqueous hydrochloric acid concentration 0.3M, carrier concentration 0.02M, stirring speed 200 rpm, pH of external aqueous buffer solution 5.5 and volume ratio of external aqueous buffer solution to emulsion phase 6. When initial copper concentration of external aqueous buffer solution was 500 ppm, copper ion could be removed to 99% from external solution in 30 min.

백서의 복강내에 투여한 Mitomycin-C-Polyglycolic acid 제형이 장기에 미치는 영향에 관한 연구

송규상,강대영,최정목,노승무,정경수,오정연,김진향,양준목,최선웅,이진호,조준식,민병무,김용백,김창식,박근성,김승영,김학용,인현빈 충남대학교 의과대학 지역사회의학연구소 1998 충남의대잡지 Vol.25 No.1

To evaluate the in-vivo effects of mitomycin-C-polyglycolic acid composite(MMC-PGA) the disk: shaped composite were implanted into the peritoneal cavity of the Sprague-Dawley rats. The pathologic changes were examined at various time points up to 12 weeks. Initially the soft tissue around the inserted disks showed capillary congestion at 3 days. Inflammatory infiltrates with foreign body giant cells appeared from the 2nd week and reached peak response at 6-8 weeks. These reaction diminished prominently at 12 weeks. No specific pathologic change was found in the liver, the kidneys, and the heart. The above results suggest that the MMC-PGA composite can serve as a new device for intraperitoneal chemotherapy of various types of cancers.

비호지킨 림프종환자에서 proMACE-cytaBOM 복합항암화학요법의 유효성에 대한 제 2상 임상시험

김성우,안명주,박석규,이영렬,정태준,최일영,김인순 한양대학교 의과대학 2000 한양의대 학술지 Vol.20 No.1

Aggressive non-Hodgkin's lymphoma by REAL classification is a heterogenous group of disease. With recent advances in combination chemotherapy, the long-term survival is improved to 40-65%. We investigated twenty-one aggressive non-Hodgkin's lymphoma patients treated with pro-MACE-cytaBOM (prednisone, adriamycin, cyclophosphamide, etoposide, cytosine arabinoside, bleomycin, vincristine and methotrexated) to determine the efficacy and toxicites. There were seven patients older than 60 years. Histologic types by REAL classification were as follows : diffuse large B cell (12/21), peripheral T cell (6/21), anaplastic large cell (2/21) and angiocentric T cell (1/21). Most of patients were classified in Stage Ⅱ-Ⅳ (20/21). According to IPI (international prognostic index) score, seven patients were included in low risk, five were low-intermediate risk, three were high-intermediated risk and six were high risk group. seventeen complete responses (85%) and two partial responses (10%) were achieved. The overall response rate was 95%. The mena disease free survival was 30 months, the mean overall survival was 29 months (range:21-36), and the median overall survival was not reached. WHO grade Ⅲ/Ⅳ neutropenia or thrombocytopenia was observed in 16.7% and 2.8%, respectively. There was no treatment-related death. These results suggest that proMACE-cytaBOM combination chemotherapy is very effective and has low toxicity in the treatment of aggressive non-Hodgkin's lymphoma even treated in elderly patients.

원형 플레이트 형태에 따른 초음파 부상 장치의 진동특성에 관한 연구

정상화,최석봉,차경래,김현욱,김광호,박준호 한국공작기계학회 2005 한국공작기계학회 춘계학술대회논문집 Vol.2005 No.-

In the semiconductor and optical industry the non-contact transportation is required for reducing the damages. The ultrasonic levitation is the solution of the problem. In this paper, the ultrasonic levitation system and 3 disk-type stator for levitation various object are proposed. The vibration modes of disks are analyzed with FEM and designed with the analysis results. The 3D vibration profiles of the disks are measured by Laser scanning vibrometer for verifying the vibration characteristics of the system. The amplitudes of the disks and the levitation heights of object are measured for evaluating the performance.

고상 에피텍시 성장을 이용한 elevated source/drain 공정연구

金湘薰,崔在植,崔圭鎭,金亨駿 弘益大學校 科學基術硏究所 1999 科學技術硏究論文集 Vol.10 No.2

Recently, semiconductor devices require the ultrashallow junctions and low leakage current. Self-implantation to make preamorphization prevents channeling and minimizes junction depth. But in this way, implantation with high energy makes defects like dislocation loop in depletion region and interface between amorphous silicon and silicon wafer. But solid phase epitaxy using low pressure chemical vapor deposition prevents channeling, allows the easy control of junction depth by amorphous layer thickness, and improves the conventional processes. Amorphous silicon films in source and drain by LPCVD are elevated from the Si substrate. This structure is called "elevated source/drain". The elevated source/drain process improves metal contact and simplify the fabrication process. Usually, the amorphously-deposited Si films by chemical vapor deposition are crystallized to polycrystalline films due to a formation of SiO₂layer at the amorphous Si/Si substrates interfaces. Formation of SiO₂layer on Si surface can be effectively prevented by flowing the Si₂H?? gas during the heating-up procedure for amorphous Si depositions. In this way, amorphously deposited Si layer onto (100) Si substrates was grown epitaxially during the post-deposition heat treatments. The suppression of surface SiO₂can be explained in terms of adsorption of SiHx adspecies, instead of oxygen from residual gases in the reactors, to Si surfaces after desorption of hydrogen from H-passivated Si surfaces. Employing Si₂H?? flowing and solid phase epitaxial growth, high-quality epitaxial Si layer was obtained at low temperatures below 500℃ without conventional high temperature cleaning procedures. Amorphous Si films on Si substrate are epitaxially grown and amorphous Si films on SiO₂layer remain as amorphous with proper heat treatments. Uncrystallized amorphous Si films on SiO₂layer can be selectively etched using the HNO₃/HF/HNO₃/CH₃COOH solution with proper mixing ratio and elevated source/drain regions were formed.

초정밀 광소자 정렬 스테이지의 구동 특성에 관한 연구

정상화,차경래,김현욱,최석봉,김광호,박준호 한국공작기계학회 2005 한국공작기계학회 춘계학술대회논문집 Vol.2005 No.-

As the optical communication is introduced to the backbone network at first and becomes a general communication method of network, the demand of kernel parts of optical communication such as PLC(Planar Light Circuit), Coupler, and WDM(Wavelength Division Multiplexing) element increases. The alignment and the attachment technology are very important in the fabrication of optical elements. In this paper, the driving mechanism of ultra precision stage is studied with the aim of optimal design of stage. The travel and the resolution of stage are investigated. The hysteresis of the stage is generated because of PZT actuator. The hysteresis and the inverse hysteresis are modeled in X, Y, and Z-axis motion. The input data of desired displacement to the stage according to input voltage is obtained from the inverse hysteresis equation. In the result of experiments with the input data, the errors due to hysteresis are well compensated.