Al계 초소성합금과 Zr계 비정질합금의 마이크로 진동성형에 관한 연구

손선천(Seon Cheon Son),박규열(Kyu Yeol Park),나영상(Young Sang Na) 한국생산제조학회 2007 한국생산제조학회지 Vol.16 No.6

Micro forming is a suited technology to manufacture very small metallic parts(several mm~㎛). Al5083 superplastic alloy with very small grains has a great advantage in achieving micro deformation under low stress due to its relatively low strength at a specific high temperature range. Micro forming of Zr?₂Cu₁?Ni₁₃Al? bulk Metallic glass(BMG) as a candidate material for this developing process are feasible at a relatively low stress in the supercooled liquid state without any crystallization during hot deformation. In this study, the micro formability of Al5083 superplastic alloy and bulk metallic glass, Zr?₂Cu₁?Ni₁₃Al?, was investigated with the specially designed micro vibration forming system using pyramid-shape, V-shape and U-shape micro die pattern. With these dies, micro vibration forming was conducted by varying the applied load, time. Micro formability was estimated by comparing the hight of formed shape using non-contact surface profiler system. The vibration load effect to metal flow in the micro die and improve the micro formability of Al5083 superplastic alloy and Zr?₂Cu₁?Ni₁₃Al? bulk Metallic glass(BMG).

Al계 초소성합금과 Zr계 비정질합금의 마이크로 진동성형에 관한 연구

손선천(Seon Cheon Son),박규열(Kyu Yeol Park),나영상(Young Sang Na) 한국생산제조학회 2007 한국공작기계학회 춘계학술대회논문집 Vol.2007 No.-

Micro forming is a suited technology to manufacture very small metallic parts(several ㎜-㎛), Al5083 superplastic alloy with very small grains has a great advantage in achieving micro deformation under low stress due to its relatively low strength at a specific high temperature range. Micro forming of Zr?₂Cu₁?Ni₁₃Al? bulk Metallic glass(BMG) as a candidate material for this developing process are feasible at a relatively low stress in the supercooled liquid state without any crystallization during hot deformation. In this study, the micro formability of Al5083 superplastic alloy and bulk metallic glass, Zr?₂Cu₁?Ni₁₃Al?, was investigated with the specially designed micro vibration forming system using pyramid-shape, V-shape and U-shape micro die pattern. With these dies, micro vibration forming was conducted by varying the applied load, time. Micro formability was estimated by comparing the hight of formed shape using non-contact surface profiler system. The vibration load was effected to metal flow in the micro die and improve the micro formability of Al5083 superplastic alloy and Zr?₂Cu₁?Ni₁₃Al? bulk Metallic glass(BMG).

진동복합하중에 따른 Al계 초소성합금과 Zr계 비정질합금의 마이크로 성형에 관한 연구

손선천(Son Seon Cheon),박규열(Park Kyu Yeol) 대한기계학회 2008 대한기계학회 춘추학술대회 Vol.2008 No.5

Micro forming is a suited technology to manufacture very small metallic parts(several ㎜~㎛). In this study, the micro forming property was studied, using Al5083 superplastic alloy with micro grain, suitable for the micro forming process and Zr-BMG amorphous with pseudo-superplastic phenomena in the supercooled liquid state. In a energy point of view, the vibrational load was useful for micro forming field. The vibrational load reduced friction and sticking slip between micro die and material and release the air static pressure bearing effect between micro die and material.

Clinical Follow-up on Sagittal Fracture at the Temporal Root of the Zygomatic Arch: Does It Need Open Reduction?

Cheon, Ji Seon,Seo, Bin Na,Yang, Jeong Yeol,Son, Kyung Min Korean Society of Plastic and Reconstructive Surge 2013 Archives of Plastic Surgery Vol.40 No.5

Background The zygoma is a major portion of the midfacial contour. When deformity occurs in this area, a reduction should be conducted to correct it. If a sagittal fracture at the temporal root of the zygomatic arch occurs, this also requires reduction, but it is difficult to approach due to its anatomical location, and the possibility of fixation is also limited. Thus, the authors attempted the reduction of sagittal fracture by two- or three-point fixation and the Gillies approach without direct manipulation. The preoperative and postoperative results of the patients were evaluated. Follow-up was performed to establish a treatment guideline. Methods A retrospective study was done with 40 patients who had sagittal fractures at the temporal root of the zygomatic arch from March 2009 to June 2012. Only two- or three-point fixation was performed for the accompanying zygomatic-orbital-maxillary fracture. The Gillies approach was used for complex fractures of the zygomatic arch, while the temporal root of the zygomatic arch was only observed without reduction. Preoperative and postoperative computed tomography and X-ray scans were performed to examine the results. Results The result of the paired t-test on preoperative and postoperative bone gap differences, the depression level, and the degree of temporal protrusion showed a marked decrease in the mean difference at a 95% confidence interval. The results were acceptable. Conclusions In the treatment of sagittal fractures at the temporal root of the zygomatic arch, it is acceptable to use indirect reduction and non-fixation methods. This leads to a satisfactory aesthetic and functional outcome.

Rifampin으로 유도된 혈소판 감소증 1례

손혜영,천선희,홍기숙 梨花女子大學校 醫科大學 醫科學硏究所 1995 EMJ (Ewha medical journal) Vol.18 No.4

Rifampin-induced thrombocytopenia has been recognized as an immunological reaction associated with intermittent high dose therapy, or after administration of rifampin fo11owing aninterruption of therapy, and rarely seen with daily low dose therapy. The patient was a 64 year-old male who was given rifampin 600mg daily for treatment of recurrent pulmonary tuberculosis. He had been received antituberculous treatment includingriftmpin 4 years ago. Spontaneous gum bleeding, petechiae on whole body, hemoptysis wasnoted two weeks after initiating the treatment. His platelet count was 5000/mm^3. Antituberculous medication was discontinued, but the platelet count was not recovered. He diedof severe hypoxemia due to pulmonary hemorrhage. With the essential use of rifampin for the treatment of tuberculosis infections, clinicianshould recognize the possible complication of this drug causing such serious immunologic reactions as thrombocytopenia, hemolytic anemia, and acute renal failure with daily or intermittenttheupy.

Retrobulbar Hematoma in Blow-Out Fracture after Open Reduction

Cheon, Ji Seon,Seo, Bin Na,Yang, Jeong Yeol,Son, Kyung Min Korean Society of Plastic and Reconstructive Surge 2013 Archives of Plastic Surgery Vol.40 No.4

Retrobulbar hemorrhage, especially when associated with visual loss, is a rare but significant complication after facial bone reconstruction. In this article, two cases of retrobulbar hematoma after surgical repair of blow-out fracture are reported. In one patient, permanent loss of vision was involved, but with the other patient, we were able to prevent this by performing immediate decompression after definite diagnosis. We present our clinical experience with regard to the treatment process and method for prevention of retrobulbar hematoma using a scalp vein set tube and a negative pressure drainage system.

면역세포화학적 방법을 이용한 폐암세포의 Carcinoembryonic Antigen (CEA) 및 Epidermal Growth Factor Receptor (EGFR) 검색에 관한 연구

천선희 ( Cheon Seon Hui ),김세규 ( Kim Se Gyu ),정현철 ( Jeong Hyeon Cheol ),장준 ( Jang Jun ),손희영 ( Son Hui Yeong ),김성규 ( Kim Seong Gyu ),이원영 ( Lee Won Yeong ),이두연 ( Lee Du Yeon ),이기범 ( Lee Gi Beom ) 대한내과학회 1992 대한내과학회지 Vol.42 No.4

연구배경 : Carcinoembryonic antigen은 oncodev-elopmental tissue glycoprotein으로 대장 및 직장암, 유방암, 페암 환자의 혈청에서 검출되어 진단 및 치료 경과의 관찰에 이용되고 있으며, Epidermal growth factor receptor는 상피세포의 세포막에 존재하는 수용체로써 EGF와 반응하여 상피세포의 분화와 증식을 조절하는 물질로 인체 세포 내에 존재하는 proto-on-cogene인 c-erb-B의 산물이며, 증가된 발현과 더불어 EGFR 또는 그와 관련된 gene의 비정상적인 발현이 상피세포암의 발현에 관여하리라 보고 있다. 방 법: 1986년 1월부터 1989년 12월까지 연세대학교 의과대학 세브란스 병원에서 원발성 폐암 진단 후 폐절제술을 시행 받고 생존 여부와 치료 성적으로 알고있는 원발성 비소세포 폐암 환자를 대상으로 CEA와 EGFR에 대한 면역세포화학적 염색을 시행하였다. 결과 : 1) 한국인 비소세포 폐암에서 CEA 발현율이 96%이었으며, EGFR발현율은 26%이었다. 2) 암세포 유형에 따른 EGFR 발현율은 편평상피암 30%, 선암 14%, 미분화암 50%이었으며, 대세포암은 4예 모두 음성 이었고, grading system 적용시 1 혹은 2 +로 발현 정도가 낮았다. 3) Grading system을 적용한 암세포 유형에 따른 CEA 발현율은 편평상피암 22%, 선암 93%, 미분화함 33%가 3 혹은 4+로, 선암의 CEA 발현율이 가장 높아TEk. 4) 대상환자의 평균 추적 기가은 2년(1~41개월)으로, 1년 생존율은 85%, 2년 생존율은 68%, 3년 생존율은 54%이었으며, EGFR 과 CEA의 발현 정도에 따른 생존율에는 차이가 없었다. 결론 : 한국인 비세포 폐암에서도 CEA와 EGFR이 발현함을 확인 하였으며, EGFR의 발현 유무가 폐암 생존율의 예후인자로 작용할 가능성 여부에 대하여서는 추후 연구가 필요할 것으로 생각된다. Background: Carcinoembryonic antigen (CEA) was defined as an endodermally derived tumor-associated antigen that was also present in fetal gastrointestinal tissues. This antigenic material has been demonstrated in the blood of a large number of patients with other neoplasms, including those arising in the lung. Epidermal Growth Factor (EGF) usually stimulate the growth and proliferation of a variety of cell types through binding to a specific cell surface receptor, a 170-KD glycoprotein, EGFR. A part of the EGFR has been found to be homologous to the product of the avian erythroblastosis virus oncogene, c-erb-B. Many squamous cell carcinoma cell lines show high levels of EGFR expression and the EGFR apparently plays an important role in the growth of squamous cell carcinoma. Methods: We have collected paraffin blocks of 100 patients with non-small cell lung cancer who were treated with surgical resection and assessed their CEA and EGFR expression with monoclonal antibodies against the CEA or EGFR by immunohistochemical stain (ABC method). Results: 1) The expression of CEA was 96% and the expression of EGFR was 26% in the Korean non-small cell lung cancer. 2) EGFR immunoreactivity was detected in 19 (30%) of the 63 epidermoid carcinomas, in 4 (14%) of the 27 adenocarcinomas and in 3 (50%) of the 6 undifferentiated carcinomas, while no EGFR immunoreactivity was found in large cell carcinomas. By using the grading system, the EGFR expression grades were low a s grade 1 or 2 +. 3) CEA immunoreactivity by using the grading system was 3 or 4 + in 14 (22%) of the 63 epidermoid carcinomas, in 25 (93%) of the 27 adenocarcinomas and in 2 (33%) of the 6 undifferentiated carcinomas. So the highest prevalence of intracellular CEA was seen in the adenocarcinomas, including the bronchoalveolar type. 4) The median follow-up duration was 2 years (1-41 months) and the 1-year survival rate was 85%, the 2-year survival rate 68% and the 3-year survival rate 54%. A correlation was not demonstrated between the expression rate of CEA or EGFR and the survival rate of lung cancer patients. Conclusions: CEA and EGFR expression in Korean non-small cell lung cancer were observed. But further studies need to be performed to determine whether EGFR expression can be prognostic of lung cancer or not.

Various clinical application of the keystone island flap in reconstructive surgery: case report

Ji Seon Cheon,Kyung Min Son,Woo Young Choi 조선대학교 의학연구원 2021 The Medical Journal of Chosun University Vol.46 No.1

There are many options for the reconstruction of various body defects in size and location. The keystone flap is a new concept in the fasciocutaneous island types. The keystone flap is an easy and reliable flap for defects that are small or medium-sized with some depth and in which skin grafting is difficult. This study presents the reconstruction of several defects, from scalp to lower extremities, ranging in size and location, using the keystone flap in five patients (six flaps).

키워드 네트워크분석을 이용한 국내 외상 후 성장 연구동향 분석

손혜선(Son, Hye-Seon),천성문(Cheon, Seong-Moon) 한국교육치료학회 2022 교육치료연구 Vol.14 No.1

본 연구는 키워드 네트워크 분석을 통한 국내 외상 후 성장 연구의 지식구조를 파악하였다. 외상 후 성장과 관련된 국내 연구에서 2010년부터 2021년까지 게재된 연구논문들 중 301편의 논문의 키워드 1,694개를 추출하였다. 수집된 자료는 Textom과 UCINET 6로 분석하였고, 전체 및 시기별, 대상별 네트워크별로 키워드간 구조를 심층적으로 분석하였다. 연구결과는 첫째, 전체 네트워크 분석을 통해 연구대상, 연구방법, 주요변인인 사회적 지지, 의도적 반추, 삶의 의미 등이 연구의 핵심주제로 나타났다. 둘째, 시기별 네트워크 분석에서는 시기 1에서 시기 2를 지나면서 연구의 방향이 개인적 변인에서 사회적 환경에 따른 외상경험에 대한 사회적 요인으로 연구의 변인이 옮겨갔으며, 종단 및 관계 연구로 연구방법이 확대되었다. 셋째, 대상별로 청소년, 성인 네트위크에서는 각각 사회적 지지, 의도적 반추, 외상경험이 동일하게 핵심주제로 나타났다. 이러한 연구의 분석 결과와 논의를 바탕으로 향후 외상 후 성장 연구에 대한 방향과 시사점을 제시하였다. This study identified the knowledge structure of domestic post-traumatic growth research through keyword network analysis. In a domestic study related to post-traumatic growth, 1,694 keywords of 301 papers were extracted out of the research papers published from 2010 to 2021. The collected data were analyzed by Textom and UCINET 6, and the structure between keywords was analyzed in depth by network by overall, period, and target. First, through the analysis of the entire network, research subjects, research methods, major variables such as social support, intentional reflection, and meaning of life were found to be key topics of the study. Second, in the analysis of the network by period, the direction of the study shifted from the personal variable to the social factor for trauma experience according to the social environment from period 1 to period 2, and the research method was expanded to longitudinal and relationship research. Third, social support, intentional rumination, and trauma experience were the same key topics in youth and adult netweek, respectively. Based on the analysis results and discussions of these studies, directions and implications for future post-traumatic growth studies were presented.

노인장기요양시설종사자의 이직의도 관리방안 연구 -역할갈등과 역할과다를 중심으로-

천기선 ( Cheon Gi-seon ),손매용 ( Son Mae-yong ),김기정 ( Kim Ki-jeong ),신영일 ( Shin Young-il ) 한국사회복지경영학회 2022 사회복지경영연구 Vol.9 No.2

초고령사회 진입을 앞두고 전문적 노인돌봄에 대한 사회적 수요가 급증하는 상황에서 요양보호사의 높은 이직은 사회적 문제가 되고 있다. 본 연구는 요양보호사의 이직의도가 장기요양기관서비스 질에 미치는 문제를 대응하기 위하여, 요양보호사의 직무스트레스가 이직의도에 미치는 직접효과를 연구하고, 직무스트레스와 이직의도의 영향관계에서 존재하는 소명의식의 매개효과 검증을 목적으로 수행되었다. 연구자료는 경기도 노인의료복지시설에 종사하는 요양보호사들을 대상으로 설문지법을 적용하여 확보하였으며, 총 340명에게 배부한 후 유효설문지 300부를 확보하여 통계프로그램 SPSS Statistics 21.0으로 처리하였다. 자료분석은 기술통계와 정규성 분석, 상관분석을 실시하였고, 직접효과와 매개효과 관련 가설은 위계적 회귀분석으로 검증하였다. 분석결과 요양보호사 직무스트레스는 이직의도와 소명의식에 유의한 영향을 미쳤으며, 요양보호사의 소명의식은 역할갈등과 이직의도 사이에서 매개효과를 갖는 것으로 분석되었다. 이를 바탕으로 요양보호사의 이직관리를 위한 방안으로 구체적으로 논의하였으며, 요양보호사의 소명의식의 매개효과를 활용하여 요양보호사의 이직의도를 감소시키는 전략을 논의하였다. In a situation where social demand for professional elderly care is rapidly increasing ahead of entering a super-aged society, high turnover of nursing care workers is becoming a social problem. In order to study the problem that high turnover of caregivers affects the quality of long-term care institutions, this study studies the direct effect of caregivers' job stress on turnover intention, and examines the relationship between job stress and turnover intention. It was conducted with the purpose of verifying the mediating effect of the sense of calling. For research data, the questionnaire method was applied to caregivers working in elderly medical welfare facilities in Gyeonggi-do, distributed to a total of 340 people, and 300 effective questionnaires were secured and processed using the statistical program SPSS Statistics 21.0. For data analysis, descriptive statistics, normality analysis, and correlation analysis were conducted, and hypotheses related to direct and mediating effects were verified by hierarchical regression analysis. As a result of the analysis, the caregiver's job stress had a significant effect on turnover intention and calling, and the caregiver's calling was analyzed to have a mediating effect between role conflict and turnover intention. Based on this, it was discussed in detail as a plan for caregiver's turnover management, and a strategy to reduce the caregiver's turnover intention by utilizing the mediating effect of the caregiver's sense of calling was discussed.