유압벌지실험을 이용한 순 티탄늄 판재의 소성유동곡선 평가(제2보)

김영석(Kim, Young-Suk),김진재(Kim, Jin-Jae) 한국산학기술학회 2016 한국산학기술학회논문지 Vol.17 No.4

본논문에서는대형 선박의 판형열교환기등에 널리 이용되고있는 순 티타늄판재의소성변형을 유한요소해석하기 위한 기초 데이터로서 순 티타늄 판재의 유동곡선을 평가하였다. 순 티타늄 판재의 프레스 가공 시에 판재에는 국부적으로 큰 소성변형이 발생하고 있다. 그러나 기존의 단축 인장실험에서 얻을 수 있는 소성변형률이 낮아서 티타늄 판재의 가공공정 설계를 위한 유한요소해석의 정밀도를 떨어뜨리는 경우가 있다. 본 연구에서는 큰 소성변형률 까지 안정적으로 성형이 가능한 유압벌지실험을 수행하여 재료의 소성변형에서 가공경화특성을 나타내는 유동곡선으로써 진응력-진변형률 선도를 구하였고 그 결과를 인장실험 결과와 비교하였다. 순 티타늄 판재의 유압벌지실험에서 재료의 변형률은 3D 디지털 영상 상관법을 이용한 ARAMIS 시스템으로 실시간 측정된다. 이 유압벌지실험으로부터는 소성 변형률이 0.65 이상 까지도 안정적으로 재료의 소성유동곡선을 얻을 수 있었으며 그 결과는 Kim-Tuan 이 문헌 17[Y.S. Kim, J.H. In, Korean Acadmia-Ind. Coop. Soc.,(be in print), 2016] 의 연구에서 제안한 가공경화식으로 잘 핏팅됨을 알 수 있었다. In this study, the plastic flow curve of commercially pure titanium sheet (CP Ti) actively used in the plate heat exchanger etc., was evaluated. The plastic flow curve known as hardening curve is a key factor needed in conducting finite element analyses (FEA) for the forming process of a sheet material. A hydraulic bulge test was performed on the CP Ti sheet and the strain in this test was measured using the DIC method and ARAMIS system. The measured true stress-true strain curve from the hydraulic bulge test (HBT) was compared with that from the tensile test. The measured true stress-true strain curve from the hydraulic bulge test showed stable plastic flow curve over the strain range of 0.7 which cannot be obtained in the case of the uniaxial tensile test. The measured true stress-true strain curve from the hydraulic bulge test can be fitted well by the hardening equation known as the Kim-Tuan model.

Immobilization with Ketamine HCI and Tiletamine-Zolazepam in Cynomolgus Monkeys

Myung-cheol Kim,Sung-hyeok Hong,Soo-jin Lee,Young-suk Kim,Jae-il Lee 대한수의학회 2003 Journal of Veterinary Science Vol.4 No.2

with Ketamine HCl and Tiletamine-Zolazepam in Cynomolgus MonkeysJae-il Lee, Sung-hyeok Hong, Soo-jin Lee, Young-suk Kim and Myung-cheol Kim*Laboratory of Veterinary Surgery, College of Veterinary Medicine, Chungnam National University, Daejeon 305-764, KoreaReceived March 4, 2003 / Accepted July 2, 2003J. Vet. Sci. (2003), 4(2), 187-191JOURNAL OFVeterinaryScience*Corresponding author: Myung-cheol Kim Laboratory of Veterinary Surgery, College of Veterinary Medicine, Chungnam National University, Daejeon 305-764, Korea Tel: +82-42-821-6757, Fax: +82-42-822-4216 E-mail: mckim@cnu.ac.kr

치상 돌기 골절의 전방 경유 나사못 고정술 치료 성적

김인영,김수한,이정길,김태선,김재휴,이제혁,강삼석 대한신경외과학회 1997 Journal of Korean neurosurgical society Vol.26 No.9

원위부 신세뇨관성 산증에서 산-염기 운반체의 결손

김혜영,한진석,전은실,진호준,주권욱,나기영,정우경,오지은,김현리,이서진,이중건,김근호,엄재호,궁성수,김진,이정상 대한신장학회 2000 대한신장학회잡지 Vol.19 No.5

T 및 B cell 測定 : 1. 1次 成績 Ⅰ. Results, Primary

金在植,崔成萬,金在龍,全東錫,朴正姬,徐相喆,金仁子,金在崇,金重明 慶北大學校 醫科大學 1982 慶北醫大誌 Vol.23 No.2

E-rosette法에 의한 T cell의 百分率과 螢光抗體法, 感作牛赤血球擔體法, 酵素抗體法 및 마우스赤血球 rosette法에 의한 B cell 의 百分率을 檢査하여 다음과 같이 요약할 수 있었다. 정상성인군의 active T cell은 26±8.2%이었고 total T cell은 72±4.9%이었다. B cell 는 螢光抗體法으로 22±5.4%, 感作牛赤血球擔體法으로 15.8±4.9%, 酵素抗體法으로 15±5.2% 그리고 mouse RBC-rosette法으로 17.2±4.1%이었다. 惡性腫瘍에 있어서 active T cell은 27.±10.4%이었고 total T cell 은 59±11.2%로서 정상인군에 비하여 유의한 감소를 보였다. 良性疾患에 있어서 T cell 은 정상인군에 비하여 유의한 차이를 볼 수 없었다. T cell percent by E-rosette and B cell by fluorescent antibody, senitized ox RBC rosette, enzyme antibody and mouse RBC rosette tests were performed. In healthy adult group the active T cell was 26±8.2% and total T cell was 72±4.9%, B cell by fluorescent antibody was 22.±5.40%, by ox RBC rosette 15.8±4.9%, by enzyme antibody 15±5.2% and by RBC-rosette 17.2±4.1%. In malignant tumor the active T cell was 27±10.4% and total T cell was 59±11.2%. In benign diseases T cell count showed no significant difference from normal adult group.

口眼渦斜 患者의 Gadolinium-DPTA enhanced MRI 所見에 대한 臨床的 考察

김재수,최우석,김용석,고형균,강성길,김창환 경희대학교 동서의학연구소 2001 東西醫學硏究所 論文集 Vol.2000 No.-

This study is designed to evaluate the clinical implications of Gd-DPTA (Gadolinium-diethyl - enetriamine pentacetic acid) enhanced MRI(Magnetic resonance imaging) in Bell's palsy and find it's usefulness in Oriental Medicine In this study, 25 outpatients with Bell's palsy were studied that MRI was performed. To evaluate degree of facial palsy, H-B(House-Brackmann) Grade was used. In Oriental Medical therapy, Acupuncture and Herbal medicine were treated. Subjective causes was divided into exposure to chill, fatigue, stress, mixed cases. Enhanced site was compared with symptoms which were disorder of eye, hearing, taste, and facial muscle palsy. Also, Relation between time which was performed MRI and enhancement was analyzed. The enhanced lesion in MRI was divided into five segments; Internal auditory canal, Labyrinthine segment, Geniculate ganglion, Tympanic segment, Mastoid segment. In Bell's palsy, 20 of 25 patients(80%) had abnormal contrast enhancement of the facial nerve. The H-B grade and interval performed MRI from onset were directly proportionate to enhancement. That is to say, Severe facial palsy short interval show high possibility of enhancement. There was no relation between subjective causes and enhanced site of facial nerve in MRI. Also Clinical symptoms didn't coincide with MRI findings.

생쥐모델에서의 망막모세포종 안구 자기공명분광법과 병리소견 : 초기경험

김동훈,김일중,양재한,김정훈,유영석,이봉재 朝鮮大學校 附設 醫學硏究所 2007 The Medical Journal of Chosun University Vol.32 No.1

Purpose: To show various MR spectroscopy and correlated pathologic images of retinoblastoma in nude mouse with a new human retinoblastom cell line (SNUOT-Rbl) which innoculated into intravitreous cavity. Materials and Methods: The established cell line was innoculated into mtravitreous cavity of 14 eyeballs of 7 mice and a transplanted retinoblastoma was examed for 1 month. Tl-weighted image (T1WI), T2-weihgted image (T2WI), and MR spectroscopy were obtained with 1.5 Tesla MRI (Magnetom Vision, Siemens, Erlangen, Germany) and 4.7 Tesla MRI (Bruker, Medizintechnik GmbH, Karlsruhe-Ettlingen, Germany). After scanning, eyeballs were extracted and hematoxylin & eosin stained specimens were examined with the microscope. We compared MR spectroscopy with pathologic findings and evaluated characters of tumors. Results: Innoculated cells into eyeball of mice grew retinoblastoma (8/14, 57%). Eyeball with retinoblastoma protruded externally and showed focal hemorrhage. Tumors showed low (n=3), iso (n=4), high (n=1) signal intensity on TIWI, low (n=5), iso (n=1), high (n=2) signal intensity on T2WI, and well enhancement (n=8) with contrast, Involvement of optic nerve was suspected by MRI and confirmed by pathology (n=1). Conclusion: We could demonstrate MR spectroscopy of transplanted retinoblastoma by new tumor cell line in vivo. This imaging technique facilitate molecular imaging investigation of retinoblastoma.

일부 의료서비스업 VDT작업자의 상지 근골격계 증상의 정도와 관련된 요인

김형렬,원종욱,송재석,김현수,김치년,노재훈 大韓産業醫學會 2003 대한직업환경의학회지 Vol.15 No.2

목적: 본 연구는 상지 근골격계 질환의 유병율이 높은 집단으로 알려진 VDT작업자를 대상으로 이들의 근골격계 통증을 정량화하고, 정량화된 통증점수를 종속변수로 하여, 이와 관련성을 갖는 작업요인, 사회심리적 요인을 파악하고자 하였다. 방법: 서울지역에 위치한 1500병상 규모의 대학병원에 근무하고 단말기 작업을 주로 수행한다고 알려진 부서에 대해 병원내 안전관리과와 협의를 거쳐 163명을 연구대상으로 선정하였다. 이중 138명이 설문에 참가하였고, 이들을 최종 연구대상으로 하였다. 설문지를 가지고 연구변수를 측정하여, 나이, 근무연수, 가사노동의 정도 등의 인구학적 변수와 직무스트레스 및 사회적지지, 근골격계 증상, 통증의 양상 등을 조사하였다. 분석방법은 일반적 특성 및 작업특성, 통증의 양상을 성별에 따라 파악하였고, 통증점수의 타당성을 검정하기 위해, 통증점수의 구성요소와 통증점수를 시각적 상사척도와 상관성 검정을 시행하였다. 통증점수를 종속변수로 하고 직무요구도, 직무재량도, 동료의지지, 상사의지지, 여러작업환경특성, 인구학적 특징 등을 독립변수로 하여 다중회귀분석을 시행하였다. 결과: 첫째 통증의 정량화를 위해 사용한 통증평정지수는 시각적 상사척도와의 상관관계가 높은 것으로 나타나, 어느 정도의 타당성을 지닌 방법으로 해석할 수 있었다. 둘째, 이 통증 점수를 종속변수로 하여, 관련요인 분석한 다중회귀분석에서 직무요구도가 높을수록 통증의 정도가 높고(p<0.01), 여성일수록 남성에 비해 높은 통증점수를 보였다(p<0.01). 결론: 근골격계 질환의 높은 유병율을 보이는 집단의 경우, 이들의 증상 유무만을 가지고 관련요인을 분석하는 방법을 사용하기 어렵다. 따라서 이런 경우, 통증을 정량화하여, 다양한 관련요인을 찾으려는 노력이 필요하며, 본 연구에서 사용한 통증평정지수는 타당성을 지닌 정량화 방법이라고 여겨진다. 또한 본 연구에서는 직무요구도가 높을수록, 여성일수록 높은 통증점수를 보였다. Objectives: This study was designed to quantify symptoms in the upper extremities and to identify the pain related factors among hospital workers using video display terminals. Methods: The subject-group consisted of 138 employees working at a hospital using video display terminals. A structured questionnaire was used to estimate the participants' general characteristics, and job contents. Job stress was measured using Karaseks JCQ(Job Content Questionnaire). Pain in the upper extremities was identified according to the NIOSH symptoms survey criteria. Quantification was measured using Kim Chul's method. Pearson's Correlation analysis was used to identify validity in quantification. VAS(visual analog scale) was used to compare with this method. Multiple regression analyses elucidated the relationship between quantified pain and various work factors, such as job stress. Data were analysed with SAS 6.12 program. Results: First, in quantification using Kim Chul's method, the correlation between modified PRS(pain rating score) and VAS was extremely high by 0.60(P<0.01), indicating the high validity of PRS. Second, the groups of high job demand, high job control, and females were related to an increased pain level. Conclusions: These results suggest that the self pain assessment method, PRS, is valuable and useful in analyzing occupational musculoskeletal symptoms. High demand, job control and gender may influence the levels of pain. Prospective studies about musculoskeletal disorder are required.

Vibrio vulnificus에 의한 패혈증 3예

김신무,김유현,신상희,오재세,강숙희,윤여안,이화재,김영옥 대한임상병리사협회 1986 임상병리사회지 Vol.18 No.1

PVA-ECC를 활용한 Half PC 복합체의 역학적 특성에 관한 실험적 연구

김재환,김영덕,김갑수,조봉석,장종호,김무한 대한건축학회 2003 대한건축학회 학술발표대회 논문집 - 계획계/구조계 Vol.23 No.2

ECC represents one particular class of HPFRCC, which are defined by an ultimate strength higher than their first cracking strength and the formation of multiple cracking during the inelastic deformation process. This study is to provide the fundamental data for the development of hybrid construction method such as the half PC(Precast concrete) reinforced by PVA-ECC, the mechanical properties of half PC according to the alteration of properties of PVA-ECC in terms of the type of fiber, Vr, S/M, placing height of PVA-ECC, are experimentally investigated. As the results. it is found that the half PCs of PVA-ECC have very higher mechanical performance in terms of yield load, strain capacity beyond yield point and maximum flexural load than that of mortar. Also, flexural crack in the half PCs of PVA-ECC are not localized at first crack and are growed to many micro crack, especially multiple cracking in specimen of P(12)-30-0.1ㆍ3 occurred.