유한요소법을 이용한 용접부의 열전달 및 잔류응력 해석에 관한 연구

김일수,김인권,문채주,정영재,안영호 韓國工作機械學會 2000 한국생산제조학회지 Vol.9 No.5

This paper represents to develop a computer software system which is capable to analyze the phase transformation of high strength steel(BV-AH32) and to predict heat transfer and welding residual stress due to phase transformation during Gas Metal Arc(GMA) welding. The developed model was considered temperature dependent properties such as young's modules, coefficient of thermal expansion and yield stress as well as the double ellipsoidal heat distribution by the moving arc. From the results, it was found that the longitudinal and transverse residual stresses calculated by the coupled analysis of heat transfer, residual stress and phase transformation showed good agreement with the experimental data. In addition, the temperature distribution as well as longitudinal and transverse residual stresses of weldment by the 1-pass and 2-pass of welding were also determined.

파종시기가 다른 일미찰의 등숙 중 호화 특성 비교

김미정, 박효진, 이유영, 김선림, 김정태, 우관식, 권영업, 정일민 忠北大學校 農業科學硏究所 2014 農業科學硏究 Vol.30 No.2

This study was conducted to investigate the pasting properties of waxy corn ‘Ilmichal’ during ripening with different sowing date. Starch content of Ilmichal was increased as matured (p<0.05). Analysis of pasting properties with waxy corn starch using a rapid visco analyser (RVA) showed linear changes in peak viscosity, trough viscosity, final viscosity, breakdown and consistency according to ripening. There were significantly positive correlation between starch content of Ilmichal and peak viscosity (0.39*), trough viscosity (0.58***), final viscosity (0.58***), and consistency (0.57**). Differential scanning calorimerty (DSC). The enthalpy of gelatinization was increased as ripening. But onset and peak temperature were decreased. There were significantly positive correlation between starch content of Ilmichal and onset temperature (0.44*), peak temperature (0.38*), and completion temperature (0.59***), on the other hand, crude protein content presented significantly negative correlation between completion temperature (-0.41*).

용접공들의 면역능에 관한 연구

이수일,조봉수,김영욱,고광욱,조원근,김영실,강수용,황인경,조병만,김돈균 大韓産業醫學會 1997 대한직업환경의학회지 Vol.9 No.1

The authors examined human immunity indicators such as CD4, CD8, Natural Killer(NK) cell, IgG, IgA, and IgM, and heavy metals such as Pb, Cr, Cd to evaluate the health hazard of welders. We selected total 126 male subjects, 60 welders who had more than 5 year working history as an exposure group, and 66 office workers and medical college students as a control group. This immunity evaluation approach is the first newly designed study that has never been tried in past studies on welder's heath evaluation. And the results were as follows. 1. Total lymphocyte count of peripheral blood was significantly higher in welder group, 2,615±650 ea/㎕ compared with 2,368±681 ea/㎕ in control group(p>0.05). 2. The proportion of CD4, CD8, NK cell in welder group was 37.5±9.4%, 24.0±8.8%, and 21.0±9.5%, respectively, and 35.5±6.5%, 25.0±6.9%, and 19.6±8.8% in control group. CD4 and NK cell were slightly higher, and CD8 was slightly lower in welder group. but there was no statistical significance between two groups(p≥0.05). 3. IgG, IgA, and IgM in welder group were 15.9㎎/㎗, 2.7㎎/㎗ and 1.5㎎/㎗, respectively, and 15.6㎎/㎗, 2.9㎎/㎗ and 1.7㎎/㎗ in control group. There was no statistical significance between two groups(p≥0.05). 4. Blood lead, cadmium and chromium concentrations were 4.2±1.8㎍/㎗, 0.4±0.38㎍/㎗, 1.2±0.6㎍/㎗ in welder group and 3.2±1.7㎍/㎗, 0.44±0.29㎍/㎗, 1.1±0.6㎍/㎗ in control group, respectively, and these value were within normal ranges.

내시경적 점막절제술로 치험한 식도 과립상 세포종 1례

강혁주,김성욱,최석진,이중현,장재식,서영범,윤병구,박건욱,김성자,김용섭,강승완,이구,양창헌,이창우,김욱년,이광헌,서정일 동국대학교 의학연구소 2000 東國醫學 Vol.7 No.-

과립상 세포종은 Schwann 세포 기원으로 생각되며 인체에 비교적 드물게 발생한다. 과립상 세포종은 전신 어느 곳에서나 발견될 수 있으나 주로 혀, 구강, 피부 혹은 유방 등에서 호발하며 드물게 위장관에서 발견된다. 위장관에서는 식도에서 가장 호발하며 다음으로 위, 대장 순이다. 과립상 세포종은 대부분, 특히 위장관에서는 양성이며 소수의 악성 병변이 보고되었다. 이러한 이유와 함께 수술 전의 진단이 어렵기 때문에 과립상 세포종에 대한 근본적인 치료는 현재까지 외과적 절제술이다. 최근에 시도되는 치료방법들로는 내시경적 레이저 치료, 용종절제술, 내시경적 점막 절제술 등이 있다. 저자들은 상부 소화관 내시경검사를 시행하여 식도 과립상 세포종을 진단하고 내시경적 점막 절제술을 시행하여 합병증 없이 퇴원하여 현재 재발없이 경과 관찰중인 1례를 경험하였기에 보고하는 바이다. Granular cell tumors, which occur infrequently, are probably of Schwann cell origin. They can occur almost anywhere in the body but usually affect the tongue, oral cavity, skin, or breasts and are rarely found in the gastrointestinal tracts. The esophagus is the most frequent gastrointestinal site, followed by the stomach and the colon. Granular cell tumors are generally benign, especially in the gastrointestinal tract, some malignant lesions have been reported. For this reason, and also because preoperative diagnosis is difficult, the standard treatment for granular cell tumor has until now been surgical excision. In recent years, other therapeutic methods is endoscopic laser therapy (ELT), polypectiomy, endoscopic mucosal resection (EMR). We report a case of esophageal granular cell tumor which was diagnosed by an endoscopy and managed using an endoscopic mucosal resection without complication.

정신분열병 환자들의 自己灣入에 관한 예비 연구

박성봉,김영미,전성일,이기철,김영훈,정영조,이영렬,이정호,최영민 大韓神經精神醫學會 1997 신경정신의학 Vol.36 No.6

목 적 : 정 신분열병 환자의 자기만입 정도에 영향을 미치는 인구학적 변인들 및 질병연관 변인들을 규명해 보고자 하였다. 또한. 환자들의 자기만입과 병식 사이의 연관성. 자기만입과 자존심 사이의 연관성을 알아보고자 하였다. 방 법 : 정신과 의사가 병록지와 면담을 통하여 대상 정신분열병 환자들의 인구학적 변인들 및 질병연관 변인들에 관한 자료를 얻고 환자들의 병식 정도를 평가한 후, 환자들로 하여금 자기보고형의 자기만입 척도와 자존심 척도를 시행하게 하였다. 총 111명의 환자가 연구대상으로 선택되었다. 결과: . 1) 여자가 남자보다 유의하게 높은 자기만입 척도 점수를 나타내었다 2) 질병연관 변인들 중 하위집단 사이에 자기만입 척도 점수의 유의한 차이를 보이는 변은 없었다. 3) 자기만입 척도 점수와 병식 점수 사이에 유의한 상관관계가 없었다. 4) 자기만입 척도 점수와 자존심 척도 점수 사이에 유의한 역상관 관계를 보였다. 결 론 : 본 예비 연구의 결과로 보아 정신분열 병 환자의 병식이 부족한 상태에서도 자기만입이 진행될 수 있으며. 자기만입이 심할수록 환자의 자존심이 저하되는 것으로 생각된다. 또한 여자 환자들이 남자 환자들보다 자기만입에 더 취약한 것으로 생각된다. 따라서 정신분열 병 환자의 이해와 치료를 위하여 자기만입에 관한 지속적인 연구가 필요할 것으로 생각된다. objective : This study was conducted to identify demographic variables and illness related variables which may affect the severity of self-engulfment in the patients with schizophrenia. We also studied the relationship between self-engulfment and insight, and the relationship between self-engulfment and self-esteem. Methods : Data on demographic variables and illness related variables for the subjects were gathered from hospital records and clinical interviews by the psychiatrists. Degree of insight for the subjects was assessed through clinical interviews by the psychiatrists. Degree of self-engulfment and self-esteem for the subjects was assessed from the self-engulfment scale and the self-esteem scale respectively. A total of 111 patients with schizophrenia were selected for statistical analysis. Results 1) The females exhibited significantly higher scores than the males on the self-engulfment scale. 2) There was no illness related variable, which exhibited a significant difference among subgroups on the self-engulfment scale. 3) There was no significant correlation between the self-engulfment scores and the insight 4) There was a significantly inverse correlation between the self-engulfment scores and the self-esteem scores. Conclusion : The results of this preliminary study suggest that self-engulfment may develop despite lack of insight and that there was inverse relationship between self-engulfment and self-esteem in the patients with schizophrenia. It also suggests that females are more subject to self-engulfment than males. So, authors suggest that it is valuable to do further studies of self-engulfment in the patients with schizophrenia.

가성동맥류의 수술적 가료

김재홍,임만빈,이창영,김일만,Kim, Jae Hong,Yim, Man Bin,Lee, Chang Young,Kim, Ill Man 대한신경외과학회 2001 Journal of Korean neurosurgical society Vol.30 No.3

Objective : Surgical experiences of pseudoaneurysms such as traumatic, mycotic and ill-defined unknown causes of aneurysms are rare. The authors have studied the results of surgical management from such cases in our series. Patients and Method : In the last 17 years, 1320 patients with cerebrovascular aneurysms were managed surgically. Among these, 16 patients showed the pseudoaneurysms. The authors analyzed retrospectively the clinical characteristics, treatment methods, management outcomes and problems in the managements. Results : There were 6 patients with traumatic aneurysm, 4 mycotic aneurysms and 6 ill-defined unknown causes of aneurysm. The sites of traumatic aneurysms were cavernous portion of the internal carotid artery(n=3), distal portion of the anterior cerebral artery (n=2) and vertebral artery(VA : n=1). Good outcomes in 5 cases could be obtained by extracranial - intracranial bypass followed by parent vessel occlusion or resection of aneurysm followed by re-anastomosis of parent vessel. The sites of mycotic aneurysm were peripheral portions of middle cerebral artery(MCA : n=3) and posterior cerebral artery(PCA : n=1). The outcomes of the patients with a mycotic aneurysm were relatively poor. It was partially due to the development of new aneurysm after treatment in one. The sites of ill-defined unknown causes of aneurysm were extracranial carotid artery(n=3), V2 portion of the VA(n=1), peripheral portion of the PCA (n=1) and MCA(n=1). Good outcome in all cases could be obtained by resection of aneurysm with or without saphenous vein graft. Conclusion : For the treatments of cerebrovascular pseudoaneurysm, combinations of aggressive medical, endovascular and surgical managements seem mandatory. Insertion of stent for a extracranial carotid artery aneurysm and coiling for a peripheral mycotic aneurysm can be option in future.

상지 단순반복작업 근로자의 수근관 증후군 유병률에 관한 조사

손지언,장태원,김윤규,홍영습,정갑열,김동일,이강진,하남진,김상범,김준연 대한산업의학회 2001 대한직업환경의학회지 Vol.13 No.3

목적 : 본 연구는 수근관 증후군의 발생위험이 높은 작업형태에 종사하는 상지 단순반복작업근로자로서 육류 및 어류 가공 사업장과 목재소 근로자에서 근전도검사를 이용하여 수근관 증후군의 유병률을 조사하고자 하였다. 방법 : 상지 단순반복작업근로자로서 육류 및 어류 가공 사업장 근로자 69명과 목재소 근로자 17명을 실험군으로, 관리직, 경리, 경비등 상지의 단순반복작업이 없는 근로자 28명을 대조군으로 선정하여, 작업적 및 병력조사, 이학적 검사와 근전도검사를 통해 수근관 증후군의 유병률을 조사하였다. 결과 : 수근관 증후군의 유병률은 육류 및 어류 가공 사업장과 목재소에서 각각 26.09 % (18명)와 29.41 %(5명)로 조사되었으며, 육류 및 어류가공사업장과 목재소 근로자를 '7년 이상과 미만의 작업기간'으로 층화하여 비교한 결과 '상지부위의 통증 호소 유무', 'Visual Analogue Scale(VAS: 총 10점) 4점 이상 여부', 'Tinel teat 양성 유무', 'Phalen test 양성 유무'는 모두 단기 작업근로자군에서 양성의 빈도가 증가되었고 '수근관 증후군 유무'는 장기작업근로자군에서 양성의 빈도가 증가되었다. 결론 : 육류 및 어류 가공 사업장과 목재소의 수근관 증후군 유병률은 각각 26.09 %와 29.41 %로 육류 및 어류 가공 사업장과 목재소는 1996년 OSHA가 지정한 바와 같이 위험한 작업요인이 있는 작업장으로 분류하여 관리되어야 할 것으로 생각된다. Objectives : This study was carried out to survey on the prevalence of Carpal Tunnel Syndrome(CTS) in high risk jobs(meat and fish processing plant and wood plant), by application of Nerve Conduction Study(NCS), a confirmatory diagnostic method. Methods : Experimental group was 69 workers sampled from meat and fish processing plants and 17 workers sampled from wood plants, who were simple, repetitive workers using upper extremities and control group was 28 workers sampled from managers, secretaries and keepers. All employees were examined through work history, physical examination and NCS. Results : 18 workers(26.09%) in meat and fish processing plants, and 5 workers(29.41%) in wood plants had compatible findings to NIOSH diagnostic criteria for CTS. The experimental group had more symptoms (complaint of upper extremities, Visual Analogue Scale ≥4(VAS: total 10 point)), signs(Tinel and Phalen test) and prevalence of CTS than control group(p<0.05). The prevalence of symptoms and signs were higher in short term workers(<7 years), but the prevalence of CTS was higher in long term workers(≥7 years). Conclusions : The prevalence of CTS in meat and fish processing plant and wood plant were 26.09% and 29.41% respectively. Authors propose that meat and fish processing and wood plants should be managed as a risk job category which were designated by OSHA in 1996

석면관련 폐질환의 진단에 있어서 흉부고해상도전산화단층촬영검사(HRCT)의 유용성

이현재,손지언,,홍영습,,이영일,예병진,유창훈,정갑열,김상훈,임형준,장은철,김정만,김준연 大韓産業醫學會 2006 대한직업환경의학회지 Vol.18 No.2

목적: 석면에 노출된 근로자에서 석면관련 폐질환의 양상을 분석하고 진단에 있어 HRCT의 유용성을 연구하여 석면에 대한 의학적 감시프로그램의 개발에 기여하고자 하였다. 방법: 석면에 직접 노출되는 작업자 68명과 간접 노출되는 작업자 94명 등 총 162명에 대해 OSHA 석면 표준, 의학적 감시 프로그램에 따라 단순 흉부방사선검사, 폐활량검사 및 우리나라 실정에 맞게 일부 수정한 의학적 설문지를 통해 면접조사의 방식으로 환자에 관한 정보를 수집하였으며, 자료의 신뢰성을 확보하기 위하여 면접조사는 1달 이상의 기간을 두고 2차례에 걸쳐 실시된 후 확인, 수정하였다. 또한, 석면관련 폐질환을 확진하기 위하여 HRCT를 추가적으로 실시하였다. 결과: HRCT결과 석면관련 폐질환의 유병율은 162명의 근로자중 17명으로 10.5%였는데, 직접 노출군에서 10명 (14.7%), 간접 노출군에서 7명 (7.4%)이었다. HRCT와 비교할 때 단순 흉부방사선검사의 민감도와 특이도는 각각 70.6%와 98.6%이었고, 양성 예측도와 음성 예측도는 각각 85.7%와 96.6%으로, HRCT는 단순흉부방사선검사에 비해 민감도가 높아 초기 석면관련 폐질환을 진단하는데 효과적이었다. 석면관련 폐질환의 진단에 있어 HRCT와 폐활량검사 사이에 유의한 관련성이 관찰되었다. HRCT 결과 석면관련 폐질환의 유무와 의학적 설문조사 결과의 빈도분석을 실시한 결과, 유의한 변수는 작업기간, 흡연량, 호흡기질환의 과거력, 기침, 호흡곤란이었다. 결론: HRCT는 석면관련 폐질환의 진단에 있어 단순 흉부방사선검사와 비교하여 민감도가 높아 초기 진단에 유용하므로 단순 흉부방사선선검사 결과 석면관련 폐질환소견을 보일 때뿐만 아니라, 정상소견을 보이더라도 폐활량 검사결과와 근무력, 흡연력, 호흡기질환의 과거력, 기침, 호흡곤란 등의 호흡기 증상을 참고하여 HRCT검사를 고려해야 한다. 또한, 본 연구에서 관련성이 없었던 요인들에 대해서도 향후 연관성을 규명하는 광범위한 전향적 연구가 필요하다. Objectives: This study was carried out to improve the medical surveillance program of workers exposed to asbestos by examining the usefulness of High Resolution Computed Tomography (HRCT) in the diagnosis of asbestos-related lung disease. Methods: The study subjects comprised 162 workers in a ship-repairing yard, 68 of whom had been directly exposed to asbestos and 94 indirectly exposed. The 'Occupational Safety & Health Administration (OSHA) asbestos standard, medical surveilance program' and HRCT were conducted to analyze the aspects of the asbestos-related lung disease. The OSHA asbestos standard, medical surveilance program consists of simple chest x-ray, spirometry and medical questionnarie. Results: Seventeen (10.5%) of the 162 subjects, 10 (14.7%) directly exposed and 7 (7.4%) indirectly exposed, revealed asbestos-related lung disease on HRCT. The sensitivity and specificity of simple chest x-ray for asbestos-related lung disease were 70.6% and 98.6%, and the positive and negative predictive values were 85.7% and 96.6% respectively, as compared with HRCT, HRCT was an effective diagnostic tool especially to detect early asbestos-related lung disease. The study results indicated a relative significant association between the results of spirometry and HRCT. The variables significantly associated with asbestos-related lung disease on HRCT were work duration, smoking history (pack-years), past history of respiratory disease, cough and dyspnea. Conclusions: In the diagnosis of asbestos-related lung disease, HRCT should be considered not only for workers with positive findings on simple chest x-ray, but also workers with specific findings on spirometry, occupational history, smoking history, and past history of respiratory disease, or with respiratory symptoms such as cough and dyspnea.

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김각현,윤영일,류병렬,윤갑준,이경원 대한임상병리사협회 2001 대한임상병리사회지 Vol.21 No.1

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