引張拘束 龜裂試驗에 依한 ABS EH32鋼 熔接部의 低溫龜裂 感受性

權海旭,金大憲,金星秀 영남대학교 공업기술연구소 1984 연구보고 Vol.12 No.1

Cracking of the welded zone of high strength steel is one of the most important factors of weldability and many kinds of test methods have been proposed to study that. In this study, cold cracking susceptibility of welded zone for high strength steel (ABS EH32 steel) with the shielded metal are welding was investigated by the tensile restraint cracking test. Effects of diffects of diffusible hydrogen contents on root cracking, lower critical stress, crack initiation and fracture method, hardness distribution of the welded zone and fractography were mainly investigated. The wet electrodes with higher diffusible hydrogen contents showed lower the critical lower stress level than the dried ones. Because of the hydrogen embrittlement, the heat affected zone by using the wet electrodes had higher hardness values than that by using the dried ones. Fracture surface of the heat affected zone with the wet electrodes showed mainly brittle fracture (intergranular and cleavage) and that of the weld metal also showed partially that due to the hydrogen embrittlement.

팥 신장기 과습처리에 의한 생육특성 및 단백질 발현

정해룡, 유장환, 윤성현, 권수정, 우선희 충북대학교 농업과학기술연구소 2022 農業科學硏究 Vol.38 No.2

Adzuki bean is sensitive to waterlogging stress. The overall study on the waterlogging stress is limited comparing to the study on the drought and any environmental stress. Therefore, the present study was conducted to investigate the changes in growth characteristics and the expression patterns of proteins at the 5-leaf stage periods of adzuki bean. The domestic cultivar, Arari (Miryang No. 8) was used to test the waterlogging stress. In the waterlogging treatment for 3 days, the plant height showed slightly decrease in the treatment at 3 days of waterlogging, but root fresh weight showed significantly changes at 3 days of the waterlogging treatment. Chlorophyll contents showed also significantly different at 3 days of waterlogging treatment compared to control the plants. The waterlogging stress gradually influenced the growth differences between the control and the treatment respectively. More than 350 pro- tein spots were identified on 2-D gels using an image analysis. Moreover, a total of 28 proteins were analyzed using LTQ-FT-ICR MS. Among these 28 proteins, a total of 18 proteins were up-regulated, and 10 proteins were down-regulated under waterlogging treatment. According to biological process, the most of the proteins were found to be involved in carbohydrate metabolism. Regarding the subcellular local- ization, most of the proteins were localized into chloroplasts in 5-leaf stage.

고주파 유도로 라이닝용 마그네시아계 내화 재료 개발

권해욱,이해성 영남대학교 공업기술연구소 2000 工業技術硏究所論文集 Vol.28 No.1

The abilities and fading behaviors of 5 different inoculants were evaluated by the thermal analyses of the melts which were held at constant temperature after addition in induction furnace. The silicon content was preserved at the high holding temperature of 1450∼1500℃, which reduced by oxidation at the low one. The inoculation temperature should be higher to obtain better and reproducible result. The inoculation performance of Ba-Si was the best on the bases of effect and fading behavior

전위된 상악 견치 및 하악 측절치의 치험례

권해숙,현홍근,김영재,김정욱,장기택,김종철,한세현,이상훈 大韓小兒齒科學會 2009 大韓小兒齒科學會誌 Vol.36 No.4

Tooth transposition is an anomaly of eruption characterized by the interchanged positions of two adjacent teeth, which is divided into complete and incomplete transposition. There are three common approaches for treating transposition: aligning the involved teeth in their transposed positions, moving them to their correct anatomic position in the arch and extracting one of the transposed teeth. Considerations in treatment plans are esthetic, function, risk of jeopardizing the roots and damaging the supporting structures, position of the root apex, developmental stages of teeth and expected compliance. The presented case reports described one maxillary canine-the first premolar transposition and two mandibular lateral incisor-canine transpositions. The former transposed teeth were arranged in their transposed position, and the latter transposed teeth were rearranged into their normal position. 치아전위란 인접한 두 치아의 위치가 서로 바뀐 치아 위치 이상을 말하며, 치관과 치근의 위치에 따라 완전전위와 불완전전위로 나눌 수 있다. 하악보다는 상악에 편측성으로 호발하며, 특히 상악 견치에서 자주 발생한다. 전위는 발견 시기와 전위된 양상에 따라 치료방법이 달라질 수 있다. 본 증례는 상악 견치와 제1소구치 간의 전위가 일어난 10세 7개월의 환아와 하악 측절치와 견치 간의 전위가 일어난 8세 11개월 환아와 8세 9개월 환아의 교정치료에 대한 것으로 양호한 치료 결과를 얻었고, 증례 별로 치료방법의 차이점에 관한 고찰을 하였기에 이를 보고하는 바이다.

회전헤드장치에서 헤드창을 고려한 박막탄성체의 수치해석

권해성,민옥기 연세대학교 산업기술연구소 1993 논문집 Vol.25 No.1

The running mechanism of flexible and thin foil above rotating protrusion is analyzed throught a numerical simulation. The scope of analysis is confined to the phenomena of elastohydrodynamic lubrication between the rotary drum with a running protrusion and thin foil. This mathematical analysis is based on the modified Reynolds equation and the equation of plate, considering the protrusion geometry and the effect of geometric nonlinearity. Finite element method is adopted as a numerical simulation method to solve the above coupled nonlinear equations. In numerical analysis, the effects of head window in rotary drum are evaluated. And the analysis results of the window model are compared with the those of no window model.

개개 치아의 inclination과 angulation을 측정하는 보조기기를 이용한 tooth positionner의 제작

권오원,황해상 대한치과교정학회 1999 대한치과교정학회지 Vol.29 No.2

교합기에 거상된 모형 상에서 각 치아의 순, 협설측경사와 근원심경사를 적절하게 조절할 수 있도록 개발된 측정기구를 교정 치료의 마무리 단계에서 술자가 원하는 보다 정확하고 좋은 교합으로 유도하는 tooth positioner의 제작을 위한 셋업 모형 제작에 이용하는 방법을 보여 주고자 한다. In this article, we introduce a new method of tooth positioner fabrication using modified T. A. R. G. to measure the inclination and angulation of individual teeth.In finishing stage of orthodontic treatment with a fixed appliance, we anticipate that tooth positioner fabricated using the described construction method provides the movement of individual tooth into a desired position : corrected inclination and angulation of teeth, extrusion,intrusion, rotation and so on.

The Effect of Dietary Lipids on CVD Risk Factors in Ovariectomized Rats

Kwon,Ja Ryong,Ahn,Hae Seon,Lee,Sang Sun 韓國營養學會 1997 Journal of Nutrition and Health Vol.30 No.4

유치 수복물에 따른 주변 법랑질의 탈회 저항성 : QLF를 이용한 연구

권해숙,현홍근,김영재,김정욱,장기택,김종철,한세현,이상훈 大韓小兒齒科學會 2010 大韓小兒齒科學會誌 Vol.37 No.1

본 연구에서는 유치 수복물의 불소 방출 여부에 따른 주변 법랑질의 탈회 저항성과 재광화 효과를 살펴보고자 하였다. 건전 유전치 48개를 16개씩 임의로 세 군으로 나누어, FiltekTM Z250(1군), F2000(2군), KetacTM N100(3군)을 사용하여 제조사의 지시에 따라 충전하였다. 3일 동안 인공 우식 병소를 유발한 후, 14일 동안 인공 타액에 담가 재광화를 유발하였다. Quantitative light-induced fluorescence(QLF)를 이용하여 실험 단계와 시간에 따른 무기질 소실량(ΔQ)의 변화를 관찰한 결과는 다음과 같다. 1. 탈회가 일어난 인공 우식 병소의 ΔQ 값은 3군, 2군, 1군 순으로 작게 나타났고, 이 중 3군은 1군에 비해 유의한 탈회 저항성을 보였다. 2. 1군, 2군, 3군 모두 재광화 1일 후부터 초기 인공 우식 병소의 ΔQ 값과 비교 시 유의한 차를 보였으며, 관찰 기간 동안 지속적인 증가 양상을 나타내었다. 3. 재광화 속도를 의미하는 Δ(ΔQ)/일 값은 각 군에서 처음 1일 동안 유의성 있게 크게 나타났으며, 그 이후 급속히 감소하였다. 4. 수복 재료에 따른 재광화 정도는 각 군 간에 유의한 차이가 없었다. The objective of this in vitro study was to detect and monitor demineralization and remineralization of primary teeth according to restorative materials using quantitative light-induced fluorescence (QLF). A single bur hole was drilled on the each sound forty eight primary anterior teeth, and the specimens were divided into three groups. The cavity was restored with FiltekTM Z250(Group 1), F2000(Group 2), KetacTM N100(Group 3) following the manufacturer's instructions. The teeth were subjected to the demineralizing buffer for 3 days, and then subjected to a remineralizing buffer for 14 days. The change of mineral loss(ΔQ) according to the stages was evaluated by QLF and the following results were obtained: 1. When demineralization was done, ΔQ was increased as follows. : Group 1 (-110.79 ± 27.77) < Group 2 (-104.84 ± 28.95) < Group 3 (-90.16 ± 21.87) : Resistance to demineralization was statistically significant in Group 3. 2. There was a statistically significant increase in ΔQ of all groups since 1st day of remineralization 3. The rate of remineralization, Δ(ΔQ)/day, showed significant high value in each group on the 1st day then decreased rapidly. 4. There was no statistically significant difference in the degree of remineralization among restorative materials.

미세혈관 협심증 환자의 임상상 및 지표에 관한 연구

박상호,온영근,김현정,이태훈,길효욱,김현건,박수진,송해정,한대희,방덕원,신원용,이내희,김성구,권영주 순천향의학연구소 2003 Journal of Soonchunhyang Medical Science Vol.9 No.1

Background : Microvascular angina or syndrom X is heterogenous and encompasses different pathogenetic entities. Several studies suggest that microvascular angina have good prognosis and occurs predominantly in postmenopausal women. Lipoprotein (a), total cholesterol, LDL-cholesterol, HDL-cholesterol, triglyceride, homocystein, CRP and fibrinogen are the independent risk factor of acute coronary syndrome and are the chief underlying cause of atherosclerosis. We investigated clinical characteristics and markers in patients with microvascular angina. Methods : We studies 23 patients diagnosed with microvascular angina and 16 control group with negative treadmill exercise test and no significant coronary angiogram. We investigated clinical characteristics in patients group and evaluated symptom during a follow-up period of 4.2± 2.5 month. Exercise time in treadmill exercise test was compared between patients and control group. We assessed the level of markers, such as lipoprotein (a), total cholesterol, LDL-cholesterol, HDL-cholesterol, triglyceride, homocystein, CRP and ESR in two groups. Results : There is no difference in age between two groups. Patients group had a tendency to increase in female, hypertension, DM, and smoking history, but there was no statistical significance difference. Exercise duration time was significantly decreased in patients with microvascular angina (p<0,05). Serum lipoprotein (a), total cholesterol, LDL-cholesterol, HDL-cholestrol, Triglyceride, ESR, Fibrinogen and Homocystein value were no significant difference between microvascular angina and control group. Only CRP was significantly high in patients with microvascular angina (p<0.05). Conclusion : There was no statistical significance difference in age, sex, hypertension, DM and smoking history between two groups but patients group had a tendency to increase the prevalence in hypertension, DM and smoking history, female. Also, Symptom improvement and disappearance in follow-up was presented in 11 patients of 19(57.9%). Exercise tolerance was worse in patients group than control group. CRP value was significantly higher in patients group than control group. There was no statistical significance difference in lipoprotein (a), total cholesterol, LDL-cholesterol, HDL-cholesterol, triglyceride, homocystein, ESR and Fibrinogen between two groups.

정상교합자의 안이평면에 대한 개개 치아의 순, 협설측경사와 근원심경사

황해상,권오원 대한치과교정학회 1998 대한치과교정학회지 Vol.28 No.5

교합기에 거상된 정상교합자 31명의 진단모형에서 치아FACC의 경사도를 측정하기 위해 약간 변형시킨 T.A.R.G.를 이용하여 안이평면에 대한 간 치아 FACC의 순, 협설측경사와 근원심경사를 측정하여 분석한 결과 다음과 같은 결론을 얻었다. ·상, 하악 각 치아의 FACC의 순, 협설측경사와 근원심경사를 측정하여 각각의 기준치를 얻었다. ·치아 FACC의 순, 협설측경사는 상, 하악 치열 모두에서 전방치아에서 후방치아로 갈수록 점점 설측으로 경사되는 경향을 보였다. ·치아 FACC의 근원심경사는 상악치열에서 중절치와 측절치는 거의 비슷한 경사도를 가지고 견치부위에서 후방치아로 갈수록 점점 원심으로 경사되는 양상을 보였고, 하악 치열에서는 전방치아에서 후방치아로 갈수록 점점 근심으로 경사되는 경향을 보였다. ·상, 하악 모든 치아에서 어느 한 치아의 치관 근원심경사와 순, 협설측경사는 인접치아들의 치관 근원심경사와 순, 협설측경사와 높은 순상관관계를 보였다. The purpose of this study was to obtain the angulation and inclination of FACC of all teeth to FH plane. Study models of 31 persons with normal occlusion were selected and mounted on the semiadjustable articulator for this study. Using T.A.R.G. with a little modified method, the angulation and inclination of FACC of all teeth to FH plane were measured and then the measurements were analyzed statistically. The obtained results were as follows. ·Mean, standard deviation, maximum value, and minimum value of the angulation and inclination of FACC of upper and lower teeth were obtained. ·The FACC in both upper and lower arch was progressively lingually-inclined from anterior teeth to posterior teeth. ·In the angulations of FACC of upper teeth, central and lateral incisor showed similar value. Yet, the FACC of the rest was progressively distally-angulated from the canine to posterior teeth. The FACC in lower arch was progressively mesially-angulated from anterior teeth to posterior teeth. ·The angulation and inclination of FACC of any tooth in both upper and lower teeth correlated strongly and positively with the angulation and inclination of FACC of adjacent tooth.