시간경과에 따른 교정용 bracket과 교정선 사이의 마찰력 변화에 관한 연구

곽춘,김진범,손우성 대한치과교정학회 1993 대한치과교정학회지 Vol.23 No.2

The friction of orthodontic appliances is recogonized to be detrimental to tooth movement. The purpose of this study was to determine the magnitude of frictional force changes between bracket(018"×025" solt) and orthodontic wires(stainless steel, cobalt-chromium, and β-titanium, 017"×0.25" rectangular) with time. The wire was secured in the bracket slot with a elastomeric ligature. Frictional forces were measured by universal testing machine. The following conclusions were obtained. 1. The frictional forces under dry condition were greater than those in saliva. 2. The frictional forces produced by cobalt-chromium wire were less than those generated by stainless steel and β-titanium wire. 3. The frictional forces increased progressively with time, and the amount of increase on first two weeks was greater than on last two weeks. 4. The change of frictional force under dry condition was greater than in artificial saliva.

차량용 점화코일 고속가공기에 관한 연구

곽상국,한창우 영남이공대학 2002 論文集 Vol.31 No.-

Automotive Ignition coil is to transform the normal battery voltage of 12V to the second voltage of approximately 20∼30KV by discharging and mutual induction., then the induction current loss should be happened by insulation resistance, increasement. In this study, the new model of high speed machine of the automotive ignition coil to solve the problem by completing the wire alignment and speeding the wire winding is introduced. By analysing mechanism of the system governing equations of the system is obtained. In these cautions it is known that the wire tension can be controlled by the constant velocity control. Which is proved by the experiment. In addtion to, it is proved that tension profile is the indicator which judges wire alignment situation by the experiment. Pm velocity controller in winding bobbin motor, PI position, PID velocity controllers in winding guide motor, tension controller in electrical brake, and tension bar make wire winding speed and tension be stable. As the result, the high speed machine of the automotive ignition coil in the winding speed of 600 RPM is developed. Therefore by compacting wire winding alignment and speeding wire winding, it is expected that the performance of automotive ignition pail should be improved, the efficiency of engine output should be increased, and the amount of the emission gas should be decreased.

모티리움 엠정(말레인산돔페리돈 12.72 mg)에 대한 한미 돔페리돈정의 생물학적 동등성

곽손혁,우종수,황성주 충남대학교 약학대학 의약품개발연구소 2002 藥學論文集 Vol.17 No.-

Bioequivalence of two domperidone maleate tablets, test drug (Hanmi Domperidone^ⓡ tablet: Hanmi Pharmaceutical Co.) and reference drug (Motilium-M^ⓡ tablet: Jassen Korea Pharm. Co.), was evaluated according to the guidelines of Korea Food and Drug Administration (KFDA). Twenty four healthy male volunteers were divided randomly into two groups and administered the drug orally at the dose of 20㎎ as domperidone in a 2×2 crossover study. There was a week washout period between administrations. Blood samples were taken at predetermined time intervals for 48hr and the plasma concentration of domperidone was determined by a HPLC method. AUC_0-48hr (area under the plasma concentration-time curve from time zero to 48hr), C_max (maximum plasma drug concentration) and T_max, (time to reach C_max) were estimated from the plasma drug concentration-time data. Analysis of variance (ANOVA) revealed no difference in AUC_0-48hr, C_max and T_max between two products. The apparent differences of these parameters between two products were less than 20% (i.e., 1.047, -0.416 and 9.347% for AUC_0-10hr, C_max and T_max, respectively). The powers (1-β) for AUC_0-48hr, C_max and T_max were over 0.99. Minimal detectable differences (Δ) at α=0.05, 1-β=0.8 were less than 20% (i.e. 11.15, 10.21 and 18.13% for AUC_0-10hr, C_max and T_max respectively). The 95% Confidence intervals (δ) for these parameters were also within ±20% (i.e. -5.49≤δ≤7.58, -6.39≤δ≤5.57 and -1.28≤δ≤19.95 for AUC_0-10hr, C_max and T_max, respectively). These results satisfied the criteria of KFDA guidelines for bioequivalence, indicating the two tablets of domperidone maleate were bioequivalent.

재식된 상악 중절치의 장기간에 걸친 추적례 : A 8-YEAR FOLLOW UP

이동우,곽지윤,김성오,이제호,최병재 大韓小兒齒科學會 2004 大韓小兒齒科學會誌 Vol.31 No.4

완전 탈구된 치아의 치료 목적은 치주인대 세포의 손상과 치수 조직의 감염에 의한 염증 반응을 예방하거나 최소화하는 것이다. 치주인대 세포의 생활력은 완전 탈구된 치아의 예후에 있어 중요한 요소인데 치주인대 세포가 생활력을 유지하는 경우 재식시 재부착을 하게 되어 최소한의 염증반응 후 신생 백악질로 회복되지만, 생활력을 상실하게 되면 심한 염증반응을 야기하게 되어 광범위한 치근 흡수와 유착이 나타나게 된다. 치근이 유착되면 특히 성장하는 어린이일 경우 치조돌기의 성장을 방해하여 저위교합을 유발하게 된다. 또한 광범위한 치근 흡수나 유착으로 인한 치아의 조기 상실은 치조골의 흡수와 인접치의 지속적인 이동을 야기하여 기능적, 심미적인 문제를 발생케 한다. 본 증례는 상악 우측 중절치의 완전 탈구 후 재식한 후 항생제 투여 및 장기간의 수산화 칼슘 적용을 통해 9년에 걸쳐 기능적, 심미적으로 양호한 결과를 얻었기에 이에 보고하는 바이다. Tooth avulsion usually causes inflammatory root resorption and ankylosis, and ankylosis cause severe functional and esthetic problems, especially in childhood. A 7-year-old female visited the Dept. of Pediatric Dentistry, Yonsei University with the chief complaint of avulsive trauma to the upper right incisor which was left dry for 40 minutes. Tooth was irrigated with saline and replanted immediately and splinted. Anti bacterial agent and anti inflammatory agent were prescribed. After 4 months of replantation slight external root resorption and apical radiolucency was seen at radiographic examination, therfore pulp extirpation and calcium hydroxide(Vitapex^(TM)) canal filling were carried out. After 16 months, root canal was filled with gutta-percha, and bleaching treatment was done. Treatment results were satisfactory both esthetically and functionally for 8 years and 5 months.

미니동종 조혈모세포 이식에서 T림프구 수용체 단클론성 항체의 이용 가능성 및 혼합 림프구 배양에서 림프구 억제효과에 대한 연구

손상균,박성원,백진호,김동환,정진태,현동우,곽동석,이재태,이규보 대한조혈모세포이식학회 1999 대한조혈모세포이식학회지 Vol.4 No.2

연구배경: 조혈모세포이식 및 조건화 치료는 원발성 질환을 제거 후 새로운 조혈세포를 이용한 공간을 마련하고 세포의 생착을 이름으로써 치료의 목표를 달성하고자 하나 심한 부작용으로 인한 높은 조기 사망률은 극복하여야 할 점이다. 저독성 조건화 처치를 하면 불충분한 면역세포의 살해로 인한 거부반응이 큰 문제가 된다. 이에 거부반응 및 이식편대숙주반응의 중요한 역할을 하는 림프구에 대한 억제작용을 갖는 단클로성 항체의 생체 내에서 효과를 추측하기 위해 DLA(Dog lymphocyte Antigen) mismatched dog의 말초혈액을 이용한 MLC assay를 시행하였다. 방법: DLA typing의 결과와 비교하기 위해 단클론성 항체 첨가 없이 DLA가 서로 다른 3마리의 말초혈액을 이용하여 서로의 MLC 반응을 비교 실험하였다. T림프구 수용체에 대한 단클론성 항체의 농도에 따른 proloferation 억제효과를 보기 위해 2, 10, 20, 200ug/ml의 농도로 DM5 (antigranulocyte antbody: 음성 대조군)와 비교하였다. 항원에 감작된 림프구에서의 D5에 대한 효과를 보기위해 장기 골수 배양 배지에서 responder를 stimulator 및 D5와 함께 3일간 배양후 세척하고 2일간의 배양후 다시 stimulator로서 재자극 후 5일 뒤에 proliferation assay를 시행하였다. 실제 이식을 시행한 donor 및 recipient의 세포를 분리하여 proliferation assay를 하여 이식 전후를 비교하였다. 결과: T림프구 수용체에 대한 단클론성 항체의 농도를 달리한 실험에서 2, 10 ,20ug/ml 모두에서 같은 농도의 DM5는 억제효과가 없는데 비해상 당한 림프구증식 억제효과가 관찰되었다. In vivo 실험에서 중용량의 방사성 치료 및 면역 억제 요법으로 DLA matched 2마리 모두에서 성공적인 생착을 확인하였다. 공여자의 mismatched sample에 대해 G-CSF를 이용한 가동화 치료전 보다 낮은 proliferation score를 보였다. 결론: T림프구 수용체에 대한 단클론성 항체는 In vitro 실험에서 T림프구의 억제효과가 관찰되었고 동물 이식에서 부작용을 줄이는 저용량의 조건화 치료 후 생착을 유도하는 면역억제제로서 그 가능성을 확인하였고 향후 그 기전에 대한 연구 및 많은 생체 실험이 필요하다고 생각된다. 재생불량성 빈혈 같은 저세포 충실도의 골수 질환이나 과거에 방사선 치료를 심하게 받은 경우는 이미 골수 내 생착을 위한 공간이 마련된 상태이므로 특별한 면역억제 요법이 가능하다면 이러한 저독성의 조건화 처치가 유용하게 응용될수 있을 것으로 전망된다. Background: The objective of this study was to evaluate the effect of anti-TCR monoclonal antibody in mixed lymphocyte culture and as a part of immunosuppressive regimens in the allogeneic stem cell transplantation. Since marrow space is empty in the patients with aplastic anemia or previous radiation and no new space for allograft needs to be created, nontoxic imminosuppressive conditioning regimens should be feasible. These may include monoclonal antibody directed against T cell receptor other surface determinants on T cell. Moncoclonal antibody (MAb) 15.9D5 raised to canine TCR α β was found to induce hyporesponsiveness to allogeneic stimulator cells in primary and secondary mixed lymphocyte culture (MLC). Methods: Anti-TCR monoclonal antibody was tested to evaluate its suppressive effect of lymphocyte activity in vitro compared with anti- granulocyte anti body and used as an immuno-suppressive agent in two recipient dogs. Four different concentration of anti-TCR MAbs was tested in MLC to know the appropriate concentration for suppressing lymphocyte proliferation, and MLC assays were serially done from blood sample of recipient dogs and donor dogs before and after transplantation. Results: Anti-TCR monoclonal antibody had significantly suppressed H3-thymidine uptake in MLC compared with anti-granulocyte antibody(control). In two recipient dogs conditioned with non-myeloablative regimens and MAb, transplanted with DLA- matched donor dogs, successful mobilizing stem cells were less reactive to the stimulator lymphocytes than the lymphocytes from the dogs not treated before. Conclusion: The precise mechanism of immunosuppression induced by anti- TCR MAb needs to be elucidated. G-CSF had a role in suppressing lymphocyte activity of donor dogs and might have a role in preventing GVHD. Non-myeloablative conditioning strategy might be useful in patients with hypoplastic marrows who require immunosuppression only (e. g. aplastic anemia) and already has some spaces for engraftment in the marrow (e. g. irradiated marrows).

강판전단벽 거동의 실험적 기초 연구

황성래,곽재혁,김원기,박홍근,전상우 대한건축학회 2003 대한건축학회 학술발표대회 논문집 - 계획계/구조계 Vol.23 No.2(구조계)

Generally, shear wall system appears to resist the lateral loads, because high-rise buildings require satisfaction of building drift limit due to lateral loads. However shear wall system used mostly concrete, in this paper steel plate shear wall use to resist the lateral loads instead of reinforced concrete wall system. But, there is lack of research and understanding of steel plate shear wall system so that no real building of such system exists in Korea. This paper demonstrates stability and serviceability of steel plate shear wall by preliminary experimental test.

새로운 무기 응집제 개발에 따른 특성

최성우,우성훈,윤철종,곽명화,서향미,박승조 동아대학교 환경문제연구소 2000 硏究報告 Vol.23 No.1

This study has carried out the coagulation tests for tannery wastewater including high-level suspended solids and organic matters to determine the optimum pH and coagulant dosage and to characterize several coagulants for coagulation. In case of optimum pH range test, we know that multi-coagulants are not only cost-effective but also applicable from acidic pH range to alkaline pH range widely, while single-coagulant are useful in limited pH range. Removal efficiency for using of the multi-coagulants appeared more efficient than that of single-coagulant. Especially, sulfates(alum-ferric sulfate : AFS & alum-magnesium sulfate : AMS) are more effective than chlorides (alum-ferric chloride : AFC & alum-magnesium chloride AMC). In comparison of residual turbidity related to settling time between alum and alum-ferric sulfate-magnesium sulfate(AFM), it took to 40 minutes using of alum but 5 minutes using of alum-ferric sulfate-magnesium sulfate(AFM) until constant residual turbidity are reached.

평가기준표에 의한 물리 실험 평가 방안

이의완,곽호원,이상우 경북대학교 과학교육연구소 1994 科學敎育硏究誌 Vol.18 No.-

We selected 17 kinds required experimental subjects according to analysis of content of the experiment in the 7 sorts of physics textbook being used at the high school, and made the assessment's standard table of the group and the individual. And we used those subjects as the method of assessment in order to increase reasonably the accomplishment of learning goal. As the result of that, experimenting behaviors turned into more active and the role of individual was made concrete. Therefore students had more interest in the experiment. Consequentely, students understood better not only the learning of the experiment but also the contents of the textbooks through the comprehension of the learning of the experiment and the improvement of ability of research.

PDP형 배면광원용 ZnO:Al 투명전도막의 전기적 특성에 미치는 열처리 효과

김병섭,이성욱,박민우,곽동주 경성대학교 공학기술연구소 2004 공학기술연구지 Vol.11 No.-

Aluminium doped zinc oxide transparent conduction film, which is widely used as a transparent electrodes for many optical devices such as solar cell, PDP, heat mirrors, etc. were prepared by the conventional DC/RF magnetron sputtering methods, using commercial ceramic target with a mixture of ZnO and Al_(2)O_(3). All the films were deposited on Corning glass substrate. The films were heat-treated up to maximum ~400℃ in order to study the effects of heat treatment on the morphological and electrical properties of ZnO:Al film. As the annealing temperature increases, both grain sizes of the film and (002) XRD peak decreases, which results in the increase of electrical resistivity. The electrical resistivity increases by 34% with increasing annealing temperature up to 400 ℃.

대청호 저질의 용출특성과 수질에 미치는 영향

정팔진,이성우,곽동희 全北大學校 附設 都市및環境硏究所 1997 都市 및 環境硏究 Vol.12 No.1

Lake eutrophication that bring about by excessive amounts of phosphorus and nitrogen becomes the main problem in Daechung Lake. To control the eutrophication like water bloom, it is important to quantify the nutrients loading and estimate the mass balance in the lake. In this paper, it was carried out to evaluate the nutrients discharging and characteristics of release in Daechung lake and investigate the effect of sediments on water quality. Also, it is suggested that the method of water quality management is required to improve it. The results of study are summarized as following ; 1. It is estimated that about 54% of input TP is accumulated in Daechung lake 2. It is surveyed that the mean range of TP release rate is 4.2∼10.1㎎/㎡·d at sampling sites of the lake 3. In order to improve the water quality of Daechung lake, it is needed the wastewater treatment plant and the sediment dredging of the lake preferentially.