벤토나이트계 安定液의 요구성능 및 최적배합설계

권영호 동양대학교 2003 동양대학교 논문집 Vol.9 No.1

The purpose of this study is to design the requirements for the materials of stabilizing slurry and to determine the optimum slurry mix design based on the bentonite that used in the in-ground diaphragm wall of LNG receiving terminal. After the materials and mix conditions of stabilizing slurry investigated and tested, materials and the optimum mix design according to testing items including funnel viscosity, fluid loss, cake thickness and specific gravity are proposed. As test results, the optimum mix design and required performances are selected as following range. the upper limit ratio of bentonite is 2.0% and polymer is 0.1% considering the funnel viscosity and dispersion agent is 0.05% considering the fluid loss. Also all materials are composed of GTC4 as bentonite, KSTP as polymer and Bentocryl as dispersion agent. All test results are satisfied our specifications for stabilizing slurry.

電流 페이저 制御方式을 이용한 高周波 인버어터에 관한 硏究

權純杰,裵英鎬 慶南大學校 附設 工業技術硏究所 1993 硏究論文集 Vol.11 No.-

전력용 반도체 소자를 이용한 가변전압, 가변주파수 고주파 인버터의 응용은 무정전 전원장치나 유도가열등 응용범위가 매우 넓다. 본 연구에서는 L,C공진회로로 링크된 2조의 full-bridge 인버어터회로를 병렬제어하는 기법을 제안하고 있으며 MOSFET로 구성된 각 인버어터는 한개의 등가스위치 모델로 되어 직렬공진 half-bridge형 고주파 인버어터 회로를 구성하고 있다. 게이트 제어기법으로 각 소자의 구동 주기를 분할 제어하여 출력전류 페이저를 합성하는 시분할 게이트 구동방식을 사용하고 이에 따른 인버어터의 회로동작 모드를 분석하고 해석 하였다. The proposed systems can be used power supplys for high power conversion and high frequency induction heating systems. This research proposes a high frequency resonant inverter consisting of equivalent half-bridge model in combination with two L-C linked full-bridge inverter circuits using MOSFET. As a output power control strategy, the time-sharing gate control method is applied. Also, analysis of operating MODE and state equations are described.

분체계 고강도 자기충전 콘크리트의 배합요인에 관한 연구

권영호 동양대학교 2008 동양대학교 논문집 Vol.13 No.1

This study describes a selecting process of the optimum mix proportion for the high strength and self-compacting concrete placed in main structures of LNG above tank. This concrete requires high strength level about 60~80MPa, low hydration heat, balance between workability and consistency without vibrating in the actual work. For this purpose, low heat Portland cement (Type Ⅳ) and fly ash(Class F) are selected and mix design factors including water-binder ratio (W/B), replacement ratio of fly ash for unit water content (165kg/㎥) are tested. As experimental results, low heat Portland cement shows lower the confined water ratio than another cement type and the optimum replacement ratio of fly ash in order to improve properties of the binder-paste shows 10% by cement weight considering test results of the confined water ratio (βp). Also, flowability of the high strength and self-compacting concrete by using fly ash about 10~20% is improved. The replacement ratio of fly ash 10% and water-binder ratio in the range of 25~27% are suitable to the design strength about 80MPa and cost. In case of the design strength about 60MPa, the replacement ratio of fly ash and water-binder ratio show 20% and 25~30% separately. Based on the results of this study, the optimum mix proportions of the high strength and self-compacting concrete will be applied to the actual construction work of LNG above tank as a new type.

대학병원 정신과 외래 환자의 약물순응도

권준수,신성웅,정영미,박경호 大韓神經精神醫學會 1997 신경정신의학 Vol.36 No.3

Objective : In view of the facts that education about diseases and realization of the need form drugs can improve compliance of the patients, we assessed the knowledge about drugs and medication compliance in psychiatric outpatients. In addition, we investigated factors that influence patients compliance to develop a model of medication compliance. Methods : One-hundred twelve male and eighty female psychiatric outpatient were asked about drug information using questionnaires. We developed a model that predicts medication compliance using chi square tests and multiple regression analysis. Results : More than a half of the patients knew at least one of the names and the effects of the drugs they had taken, but many of them didn't know the side effects of drugs. About eighty percent of the patients showed good compliance. Knowledge of side effects, belief in the benefits of drugs, and level of education could predict medication compliance reliably. Conclusions : Because education level could not be managed by physician, we could enhance compliance through education about drug side effects and benefits of medications.

하악전돌증환자의 악교정수술후 하악각변화에 관한 임상적 분석

권영호,장현중,이상한 대한악안면성형재건외과학회 2000 Maxillofacial Plastic Reconstructive Surgery Vol.22 No.2

Predictional study for lateral change between pre- and post-orthognathic surgery has been emphasized mainly on anterior area of lateral profile ; upper lip, lower lip and chin et al. So interest for lateral profile change has been less in posterior area of lateral profile and literature analyzing gonial angle change is rare. The purpose of this study is to make prediction for gonial angle change possible and to offer somewhat treatment guidance for gonial angle to be improved by investigating overall gonial angle change between pre- and post-orthognathic surgery and inquiring into factors influencing on pattern of genial angle change. For this study 35 patients were selected retrospectively. Lateral cephalometric radiographs were taken in just pre-op time, pod 1 day, pod 1 year. They were analyzed and genial angles were measured. The results were as follows : 1.Gonial angle at pod 1 day was decreased about 9.3˚than pre-op and gonial angle at pod 1 year was increased about 4.0˚than pod 1 day. So genial angle at pod 1 year was decreased about 5.3˚than pre-op genial angle(p<0.01). 2.Mean pre-op gonial angle was 129.4˚, showing significantly high value than normal and mean gonial angle at pod 1 year was 124.1˚, showing value near to normal. 3.Mean gonial angle change between pre-op and pod 1 year was decreased about 5.4˚ in female and 5.3˚ in male. There was no statistically significant difference between male and female(p>0.05). 4.Principal factor influencing on decreased gonial angle in gonial angle change between pre-op and pod 1 year was amount of mandibular setback. 5.Principal factor influencing on increased gonial angle in gonial angle change between pod 1 day and pod 1 year was % horizontal relapse, and it was thought that resorption and bone remodelling on posterior area in mandibular distal segment also were related to increased gonial angle. 6.It is thought that sagittal split ramus osteotomy in mandibular prognathic patients with high value of gonial angle is effective to improvement of gonial angle, and In patients who have normal range of gonial angle and are required with excessive mandibular setback, short lingual cut method, additional resection of posterior margin of distal segment, Obwegeser II method will be considerd. 7.More prudent operation and careful post-op management will be responsible for maintenance of post-operactive stable gonial angle.

Antioxidant and Anti-Inflammatory Effects of Rhei Rhizoma and Coptidis Rhizoma Mixture on Reflux Esophagitis in Rats

Kwon, O Jun,Kim, Min Yeong,Shin, Sung Ho,Lee, Ah Reum,Lee, Joo Young,Seo, Bu-il,Shin, Mi-Rae,Choi, Hyun Gyu,Kim, Jeong Ah,Min, Byung Sun,Kim, Gyo-Nam,Noh, Jeong Sook,Rhee, Man Hee,Roh, Seong-Soo Hindawi Publishing Corporation 2016 Evidence-based Complementary and Alternative Medic Vol.2016 No.-

<P>The purpose of this study was to investigate the antioxidant and anti-inflammatory effects of the combined extract of Rhei rhizoma and Coptidis rhizoma (RC-mix) in experimental model of acute reflux esophagitis. The antioxidant activity was assessed by<I> in vitro</I> 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) assays. RC-mix was given at 100, 200, and 400 mg/kg body weight 2 h prior to induction of reflux esophagitis (RE). After 5 h, the effects of RC-mix treated rats were compared with those of normal and control rats. The representative flavonoid contents of RC-mix, such as sennoside A, epiberberine, coptisine, palmatine, and berberine, were detected using HPLC. The elevated esophageal mucosa damage was markedly ameliorated by RC-mix treatment in a dose-dependent manner. Furthermore, the administration of RC-mix reduced the increase of serum reactive oxygen species (ROS) and peroxynitrite (ONOO<SUP>−</SUP>). The improvement of superoxide dismutase (SOD) and heme oxygenase-1 (HO-1) levels were marked in the group given RC-mix. Moreover, the elevation of inflammatory mediators and cytokines by nuclear factor-kappa B (NF-<I>κ</I>B) activation in control rats decreased by RC-mix pretreatment. These results indicate that RC-mix treatment reduces the pathological states of esophagitis<I> via</I> regulating NF-<I>κ</I>B mediated inflammation related to oxidative stress. </P>

크롬(Ⅵ)의 체내 흡수와 소실속도에 관한 연구

김현영,이성배,임철홍,이권섭,정용현,이종성,한정희,전윤석,황호순,이용묵 한국산업위생학회 2003 한국산업보건학회지 Vol.13 No.1

The CrO3 mostly used in plating. metal surface disposal, leather, cosmetic manufacturing, as an experiment material by repeatedly inhaling and exposure the male S.D. rats at a 0.00, 0.2., 0.50, 1.25 mg/㎡ concentration(particle size: 0.5-0.5 aerosol)6hours a day, 5day a week in 13weeks comparing with 2weeks, 8weeks of recovery group about the noxiousness of the experiment animal and the reduce scale of the CrO3 in the internal organ especially in blook and respiratory organ with the period of convalescent and clearance. The experiment results which we received are as follows. 1. In blood the RBC, HGB and HCT experiment, rats with 0.20, 0.50 mg/㎡ concentration showed that there were some decreases but not dependent. The kidneys absolute weight compared with control group was reduced intentionally(p〈0.05) and the lungs absolute weight compared with control group showed intentional increase(p〉0.05). 2. After the exposure of the experiment material, the whole blook, l\blood plasma and red blood cell in blood by (x): the period of convalescent, per (y); the decreasing of Cr concentration, was y=66.51 e -0.057x, y=67.2 e-0.101x, y=70.01 e-0.030 in 0.50 mg/㎡ exposure concentration by calculating the clearance coefficient of correlation, and the half life (day)was estimated 12.0, 6086, 23.0 each. 3, After the exposure of the experiment material, the experiment animals lung, liver and kidneys by(x); the period of convalescent, per (y); the decreasing of Cr conentration, was y=1808 e-0.00493x, y=12.02e-0.0297x, y=67.61 e-0.0292x in 0.50mg/㎡ exposure concentration by calculating the clearance coefficient of correlation, and the half life(day)was estimated 140.6, 23.3, 23.7, each, and including lung, liver with all of the experiment internal organs, the Cr clearance decreased as the exposure concentration increased.

탄소섬유시트에 의한 슬래브 보강에 관한 실험적 연구

박호완,박기영,권혁문 영남대학교 공업기술연구소 2000 工業技術硏究所論文集 Vol.28 No.1

Recently, Carbon Fiber Sheets(CFS) have been used for strengthening the deteriorated RC beams and slabs because of its resistant capacity of corrosion and easy repairing works. In this study, the static tests are performed on RC slabs strengthened with CFS. Test results show that ultimate strength of specimens strengthened with CFS is Increased as 6∼37% comparing to the control specimen. Test parameters are the shape of strengthening, the number of sheet layer and the dry condition of concrete. Deflection, failure load, strains of reinforcing bar, concrete and carbon fiber sheet are measured from tests(one points loading). The failure mode and the most suitable spacing and width of CFS are discussed from these measured data. Each of one-on-one strengthening of a pure interval and width of Carbon Fiber Sheet(CFS) 25 centimeters specimen has the advantage of the ultimate load. Because strengthening method of regular intervals than method of the whole check un aspect of crack progres. It has the advantage of an aspect of maintenance management and it has load-resisting similar to method of the whole surface strengthening as a layer is large in number. Because moisture contents of concrete have an effect on strengthening capacity, when CFS was bonded, the primer affirmed for moisture will be developed.

등가 Half-bridge모델 공진형 고주파 인버터

배영호,이현우,홍성태,서기영,차영문,권순걸 慶南大學校 附設 工業技術硏究所 1992 硏究論文集 Vol.10 No.-

이 논문은 MOSFET로 구성된 등가 Half-bridge형 고주파공진형 인버어터에 대해 기술하고 있다. 시분할 방식에 의한 게이트회로를 구성하여 구동함으로써 출력단에는 두개의 인버어터에서 동작되는 순시위상이 합성되어 있어 나타나므로 부하단 출력주파수는 소자의 수위칭주파수에 대해 두배가 되고 수위칭 손실이 경감되어 소자의 평균전류가 증가한다. This paper proposes a high frequency resonant inverter consisting of equivalent half bridge model using MOSFET. In this paper time-sharing control method is applied. as a result the output frequency is two times as high as switching frequency of device and average current of device is increased because of decreasing switching loss.

완전탈구된 치아의 재식에 관한 치험례

최영철,권오연,김광철,이긍호 大韓小兒齒科學會 1993 大韓小兒齒科學會誌 Vol.20 No.2

Exarticulation includes all cases in which the tooth has been totally displaced out of its socket. The main etilogies in the permanent dentition are direct blows and traffic accident, while in the primary dentition are fall-downs. The prognosis of tooth which has been recieved endodontic treatment after replantation is better than received endodontic treatment before replantation. Ca(OH)₂as a initial canal filling material diminishes undesirable replacement root resorption, so in the cases of compelted and uncompleted root formation, the pulp is extirpated and then a Ca(OH)₂dressing is placed until optimal stage for final canal filling with gutta percha cones. Storage media and storage period of avulsed tooth is very important things for prognosis after replantation. A strong relationship has been found between dry storage or storage in non physiologic media (c.g tapwater) and root resorption. Physiologic saline and/or fresh milk is one of the best storage media.