치아 순면 형태가 측색 기기를 이용한 치아 색상 측정 결과에 미치는 영향

최용진,박수정,조현구,황윤찬,오원만,박병주,황인남 대한치과보존학회 2007 Restorative Dentistry & Endodontics Vol.32 No.5

영구형 항서맥 심박조율기 환자의 장기추적관찰

최현석,이무용,최영진,최성준,김효수,손대원,오병희,이명묵,박영배,최윤식,이영우,이명용 대한순환기학회 1998 Korean Circulation Journal Vol.28 No.5

컴퓨터 미디어와 컨조인트 분석방법을 이용한 소형아파트 평면구성 요소에 대한 거주자 선호분석 : 김해지역 공동주거 평면디자인 개발을 위한 연구

오찬옥,김석태,최병숙 대한건축학회 2004 대한건축학회논문집 Vol.20 No.5

The purpose of this study was to grasp the housing preference of the occupants living in the apartment complex by using a conjoint analysis and the computer media. The subjects were 108 housewives who lived in the small sized housing units in New Apartment Complex, Gimhae. First, four elements from previous research were selected on the basis of this study: the size of master bedroom and living room, the openness of living room from entrance, the openness of kitchen/dining room from living room, and whether or not a bathtub or a shower is in bathroom. Second, eight floor plans were combined on the results of orthoplan for four elements of unit plan, and visualized by computer media. Then, the subjects answered in order what plan they prefer. The results were as follows: The size of master bedroom and living room was the most important element when the occupants selected unit plan but the openness of living room from entrance was not. By the occupants, the ideal unit plan was suggested as follows; the living room was larger than master bedroom, the kitchen/dining room was separated from living room, and there is a bathtub in bathroom. Also, this preferred unit plan was significantly different according to the occupants' characteristics such as age, family size, family life cycle, and homeownership.

Paraquat 유도 폐독성에 대한 Hydroxycinnamic Acid계 화합물의 독성 경감 효과 (Ⅲ)

최병기,오은정,정세영 한국환경독성학회 1999 환경독성보건학회지 Vol.14 No.3

The scavenging effects of two hyaroxycinnamic acids such as caffeic acid and chlorogenic acid on paraquat induced pulmonary toxicity were investigated. The results are summerized as follows: 1. In the 5-lipoxygenase assay, caffeic acid and chlorogenic acid inhibited the enzyme activities whose inhibition concentration (IC_(50)) were 4.1 and 9.6 μM respectively. 2. To evaluate the antiinflammatory effects on mediator related to the mechanism of inflammation, ADP-induced platelet aggregation assay and histamine degranulation assay were used. Caffeic acid and chlorogenic acid inhibited on ADP-induced platelet aggregation and histamine release at a concentration dependent manners. 3. Arachidonic acid--induced ear edema were inhibited by administration of caffeic acid and chlorogenic acid. 4. Cytologicad analysis of branchoalveolar lavage fluid (BALF) which was the useful tool for detection of an inflammatory response in the lungs of animals intoxicated with chemicals were used. Alveolar macrophages and neutrophils in BALF, as well as the protein content and the LDH activity in BALF supernatant increased by intoxication of paraquat, but decreased by administration of caffeic acid and chlorogenic acid. Therefore, two hydroxyeinnamic acids tested were the useful candidates for scavenger and antiinflammatory agents on paraquat induced pulmonary toxicity.

치아의 견인을 위한 버튼 접착시 오염이 인장강도에 미치는 영향

최병재,김성오,이제호,손흥규 大韓小兒齒科學會 1998 大韓小兒齒科學會誌 Vol.25 No.2

We already know that it is very difficult to obtain an 'isolated field' for direct bonding during the surgical exposure of unerupted teeth. The aim of this in-vitro study is to simulate the clinical situation of forced eruption and to evaluate the tensile strengths of preligatured button with several types of contamination which can happen during the surgical exposure of unerupted teeth. Four orthodontic direct bonding systems were used. (Ortho-One, Rely-a-Bond, Ortho-Two, PhaseⅡ) Each material was divided into four groups(n=20) : Group 1. (Control, no contamination), Group 2. (Rinse etching agent with saline instead of water), Group 3. (Blood contamination of etched surface for 30 seconds), Group 4. (Blood contamination of primed surface for 30 seconds) 320 bovine anterior permanent teeth were divided into the above mentioned 16 groups. Enamel surface was flattened and ground under water coolant. Pre-ligatured buttons were prepared to the same form. (Cut 0.25 ligature wire 10 cm in length. Twist the ligature wire 30 times clockwise. Mark the wire 15mm and 35mm points from button. Make a loop sticking two points together and twist the loop 6 times counterclockwise.) The bonded specimens were stored at 37℃ saline solution for 3 days. then the tensile strength of each sample was measured with Instron universal testing machine, crosshead speed of 0.5mm/min. the following results were obtained : 1. As compared to control groups (Group 1) of each material, Rely-a-Bond had a significantly lower mean tensile strengths than other material. (p<0.01) 2. In Group 2. of Ortho-One and Rely-a-Bond, the mean tensile strengths decreased about 7.7% and 11.1%, respectively with statistical significances. (p<0.05) 3. In Group 2. of Ortho-Two and PhaseⅡ, the mean tensile strengths did not decrease. 4. In Group 3. of Ortho-One, Rely-a-Bond, Ortho-Two, and PhaseⅡ, the mean tensile strengths decreased about 60.8%, 56.1%, 60.2%, and 46.0%, respectively with statistical significances. (p<0.01) 5. In Group 4. of Ortho-One and Rely-a-Bond, the mean tensile strengths did not decrease. 6. In Group 4. of Ortho-Two and PhaseⅡ, the mean tensile strengths were decreased about 20.95% and 22.28%, respectively with statistical significances. (p<0.01) There were formations of a hump shaped mass from bonding resin under blood contamination which disturbed direct bonding procedure. According to Reynolds, the proper bond strength for clinical manipulation should be at least 45N or about 4.5Kg.F. According to these results, it can be concluded that Ortho-One could be used during surgical exposure of unerupted teeth. In any case, blood contamination of the etched surface should be avoided, but the blood contamination of primed surface of Ortho-One may not decrease bond strength. Just 'blowing-out' is enough to remove blood from primed surface of Ortho-One. You can verify the clean surface of the primer of Ortho-One after blowing out the blood contamination.

코크스 폐수를 이용한 활성슬러지 모델 파라미터의 민감도 분석

오재일,이병준,심효영,최상교 대한상하수도학회 2002 상하수도학회지 Vol.16 No.3

Activated sludge model (ASM, IAWQ Task Group) was developed as a general mathematical model to express major biological processes in municipal wastewater treatment. Therefore this model could be applied for the design of a wastewater treatment plant and used for finding optimal conditions in plant operation. Since biological processes adopting biodegradation have been also used to treat lots of industrial wastewater such as coke's wastewater, it is worthy to examine the applicability of ASM on the industrial wastewater treatment. In order to evaluate this possibility, the sensitivity analysis of seven parameters (Y_H,μ_H, b_H, k_h, K_S, K_(O,H), K_x) in ASM was conducted with regard to the SCOD (soluble chemical oxygen demand) removal in coke's wastewater treatment. It has shown that μ_H (maximum specific growth rate) of ASM was the most sensitive one in the SCOD removal process, and relative sensitivity was decided in order of μ_H >> b_H, K_S > Y_H, K_(O,H), K_h, K_x, consequently. Based on the sensitivity analysis and calibration procedure of ASM with the data from coke's plant, the decided parameter values were valid for the proper simulation of this industrial wastewater plant, showing adequate fitting between real and simulated data. In summary, the mathematical model of ASM was suitable for the simulation of coke's wastewater treatment plant.

전로제강 슬래그(BOF-Slag)를 이용한 고온탈황에 관한 연구

오광중,정덕영,최성원,조상원,손병현 釜山大學校生産技術硏究所 1996 生産技術硏究所論文集 Vol.51 No.-

고온 석탄연료가스의 탈황에 BOF-Slag의 이용가능성을 실험해 보았다. BOR-Slag의 온도, 유량, 탈황제의 특성등이 H₂S 제거효율에 미치는 영향을 조사해 본 결과, 최적의 H₂S 제거효율은 700℃에서 이루어졌고 입자크기가 작을수록 황포집능은 향상되었으나 0.214-0.631mm에서는 큰 영향이 발견되지 않았다. 조업온도 800℃이상에서는 탈황제의 응집으로 내부물질전달저항이 증가하여 탈황제의 반응성이 저하되었다. Experiments have been made to test the practical feasibility of using BOF-Slag to desulfurize hot coal-derived fuel gas. In this study, the effects of particle size, temperature, flow rate and sorbent characteristics on the H₂S removal efficiency of BOF-Slag were investigated. Experimental results showed that the removal efficiency of H₂S was optimum when the temperature was about 700℃ and the smaller sample size, the better sorbent capacity had and the sample size in the range of 0.214∼0.631mm didn't influence. When the temperature was above 800℃, the reactivity of sorbent has lowered because agglomeration of sorbent increased intraparticle transport resistance.

고속 가공기의 스핀들 진동에 영향을 주는 요소 분석

최영호,윤두표,김광영,최병오 한국공작기계학회 2001 한국공작기계학회 춘계학술대회논문집 Vol.2001 No.-

In this paper, We have studied on the critical vibration limits of spindle unit for the high speed ball pen tip processing machine. The vibration of bearing can be measured by FFT, and the influence of vibration amplitude due to the Unbalance, bearing deflect, bite and timing belts tension are analyzed. So, the critical vibration limits of spindle is determined by the X, Z directional vibration of spindle Unit.

급성 백혈병 환자에서 수두양 피부병변을 보인 파종성 Fusarium 감염 1예와 국내 파종성 Fusarium 감염증에 대한 고찰

오수진,정희선,김준성,김태석,조병식,최수미,김명신,이연수,이석,신완식 대한감염학회 2007 감염과 화학요법 Vol.39 No.5

최근 면역저하환자의 증가와 함에 국내에서도 점차 침습성, 파종성 Fusarium 감염증 보고가 증가하고 있다. Fusarium 감염은 아스페르길루스 감염과 유사한 임상양상을 보이지만 특징적인 피부병변을 동반하고 혈액배양에서 균이 분리되는 경우가 더 많다. 저자들은 급성 림프구성 백혈병으로 진단받고 치료중인 30세 남자 환자에서 중증의 호중구 감소 상태에서 비특이적인 피부병변을 동반한 파종성 Fusarium 혈류감염을 경험하였기에 국내 증례 고찰과 함께 보고하는 바이다. 환자의 초기 피부병변은 구진에서 시작하여 주로 소포성 병변과 일부 통증을 동반한 결절 등 여러 형태로 나타났고, Tzank 도말검사 양성으로 비정형 수두로 오인되었다. 이후 피부병변은 농포로 변하였고, 혈액배양 및 피부 조직검사에서 파종성 Fusarium 감염으로 진단받았다. 환자는 liposomal amphotericin B, voriconazole 병합요법과 G-CSF 투여, 과립구 수혈을 받았으나, 호중구 감소증에서 회복하지 못하고 급성 호흡곤란증후군과 다장기 기능부전으로 사망하였다. 본 증례는 파종성 Fusarium 감염의 경우에도 수두양 병변으로 비특이적인 양상으로 나타날 수 있으므로, 감별진단을 위해 적극적으로 혈액배양과 피부조직검사를 시행해야 함을 보여준다. Recently, we experienced a case of disseminated fusarial blood stream infection with varicelloid skin eruptions, who had suffered from persistent neutropenic fever after salvage chemotherapy for relapsed acute lymphocytic leukemia (ALL). Neutropenia continued in spite of G-CSF and granulocyte transfusion, and he failed to respond to conventional amphotericin B initially, and then liposomal amphotericin B and voriconazole combination therapy. Disseminated fusariosis can be diagnosed by blood cultures in 50% of patients and present skin lesions in more than 80% of patients. So, typical skin lesions are important clue to diagnose of the disseminated fusariosis. However, many skin lesions in immunocompromised hosts are due to various infectious and non-infectious causes. So, this case shows that it is important to obtain biopsy specimens of skin lesions for histopathologic examination, culture and staining. Here, we present our case with the review of the literatures reported in our country, so far.

Paraquat 유도 간독성에 대한 Hydroxycinnamic acid계 화합물의 독성 경감 효과 (Ⅱ)

최병기,오은정 한국환경독성학회 1999 환경독성보건학회지 Vol.14 No.3

Antioxidative and scavenging effects were investigated by using two hyaroxycinnamic acids (caffeetannins), such as caffeic acid and chlorogenic acid, on oxidative stress and hepatotoxicity that induced by paraquat. The results are summerized as follows: 1. To assess radical scavenging ability, reduction concentration (IC_(50)) of 1.1 diphenyl-2-dipicrylhydrazine (DPPH) were measured. IC_(50) values of caffeic acid and chlorogenic acid were 29.7±0.6μM and 26.0± 0.5μM respectively. Their radical scavenging activities showed concentration-dependent manner. 2. In H₂0₂-induced hemolysis assay to rat blood, caffeic acid and chlorogenic acid led to different effects, whose hemolysis inhibition ratios at 100 μM were 45.2±7.1 % and 11.6±3.1 % respectively. 3. In hypoxanthine-xanthine oxidase system producing superoxide anion, caffeic acid and chlorogenic acid showed different inhibitory activities of xanthine oxidase showing 36.8±4.3% and 5.4±2.3% respectively. 4. To microsomal NADPH dependent cytochrome p-450 reductase in rat liver, paraquat consumed NADPH at a dose-dependent manner from 0 to 1 μM paraquat concentration. Caffeic acid and chlorogenic acid blocked NADPH consumption rates at concentration-dependent manner and inhibition ratios at 100 μM were 67.6%% and 59.2% respectively. 5. Administration (30mg/kg, iv) of paraquat to rats caused the marked elevation of glutamic oxaloacetic transaminase (GOT), glutamic pyruvic transaminase (GPT), lactate dehydrogenase (LDH), alkaline phosphatase (ALP) and lipid peroxides (LPO) in the serum and lipid peroxides in the microsome as compared to the control group. Serum GOT, GPT, LDH, ALP and LPO and liver microsomal LPO were reduced significantly by caffeic acid (50mg/kg), chlorogenic acid (25mg/kg) and silymarin (150mg/kg) as compared to the paraquat group. From these results, caffeic acid and chlorogenic acid exerted their antioxidative agents by removing reactive oxygen substance (ROS) and scavenging effects by inhibiting ROS generating enzyme. As a general, two hydroxyeinnamic acids showed the useful compounds for scavenger and reducer on the paraquat induced hepatotoxicity.