고속가공을 위한 검사시편에 관한 연구

정종윤,황영수,이춘만,정원지,고태조 한국공작기계학회 2003 한국생산제조학회지 Vol.12 No.4

The properties of a machine tool greatly affect machining quality since a machine tool has large variance in its features. Machine tool makers want to find best machining condition with the one that they have built. Machine builders need to develop test specimen since it helps finding characteristics of machine tools when the machining properties of the specimen are analyzed. This paper develops test specimen to identify features of the main spindle, the feeding device, and the frame of a machine tool. The specimen is machined with a high speed machine and the features of the machine are analyzed with test items. They are surface roughness, overshoot in axial movement, errors in circular movement, feeding with small movement, and compensational error. This work can improve usability for a machine tool in machining practice.

가솔린기관의 운전조건에 따른 배출가스 특성에 관한 硏究

黃光性,鄭鳳守,金泰圭 진주산업대학교 2000 산업과학기술연구소보 Vol.- No.7

The amount of carbon of dioxide, carbon hydroxide and nitrogen oxides produced from gasoline engine were detected by adjusting throttle valve and engine speed and increasing intaking temperature for combustion, and the results were as follows 1. The amount of CO produced decreased by intaking temperature of air increase where as it increased by increasing engine speed and closing the throttle valve. 2. The amount of HC produced decreased by increasing the intaking air, enlarging the throttle and by increasing the engine speed, but it increased carbon hydroxides more than 2400rpm at 120℃ 3. The amount of NOx produced maximized when throttle open 120˚ and speed reached 2200rpm and increased it by increasing temperature of outer air.

결핵균체 추출액으로부터 알파 및 베타단백항원의 정제에 관한 연구

황인택,백태현,김화중,박정규,최대경 충남대학교 의과대학 지역사회의학연구소 1990 충남의대잡지 Vol.17 No.1

It is well known that α- and β-antigens are major protein products of Mycobacterium tuberculosis. Alpha and beta antigens from the cell extract of Mycobacterium tuberculosis were purified by 80% ammonium sulfate precipitation, gel filtration of Sephacryl S-300, DEAE-Sephacel ion exchange chromatography and hydroxylapatite chromatography. Beta antigen was purified further by column preparative polyacrylamide gel electrophoresis. The purified alpha and beta antigens were checked degree of purified by SDS-polyacrylamide gel electrophoresis. The results were summarized as follows: 1. Alpha antigen was purified by ammonium sulfate precipitation, gel filtration, ion exchange chromatography and hydroxylapatite chromatography. The purified alpha antigen showed a distinct band of 30 KDa molecule on SDS-polyacrylamide gel electrophresis. 2. Beta antigen was purified by ammonium sulfate precipitation, gel filtration, ion-exchange chromatography, hydroxylapatite chromatography and column preparative polyacrylamide gel electophoresis. The purified beta antigen showed two distinct bands of 83 KDa and 52 KDa molecules on SDS-PAGE. 3. Especially, Beta antigen was absorbed well to hydroxylapatite column but alpha antigen was passed completely without absorption.

코호넨 네트워크 및 시간 지연 신경망을 이용한 움직이는 물체의 중심점 탐지 및 동작특성 분석에 관한 연구

황정구,김종영,장태정 江原大學校 産業技術硏究所 2001 産業技術硏究 Vol.21 No.B

In this paper, center detection and motion analysis of a moving object are studied. Kohonen's self-organizing neural network models are used for the moving objects tracking and time delay neural networks are used for dynamic characteristic analysis. Instead of objects brightness, neuron projections by Kohonen Networks are used. The motion of target objects can be analyzed by using the differential neuron image between the two projections. The differential neuron image which is made by two consecutive neuron projections is used for center detection and moving objects tracking. The two differential neuron images which are made by three consecutive neuron projections are used for the moving trajectory estimation. It is possible to distinguish 8 directions of a moving trajectory with two frames and 16 directions with three frames.

Switched Reluctance Motor의 진동·소음의 억제에 관한 연구

황영문,이종근,정태욱 釜山大學校生産技術硏究所 1999 生産技術硏究所論文集 Vol.56 No.-

SRM드라이브는 여러 가지 장점에도 불구하고 기존의 전동기에 비해 상당히 큰 진동·소음이 발생하며 이것은 SRM드라이브의 상용화에 큰 걸림돌로 작용하고 있다. SRM드라이브의 주된 진동·소음의 발생원인은 상간 콤뮤테이션시 감자전압 인가에 따른 급작스러운 소호작용에 의한 방사방향의 급격한 가진력 변화에 기인하며 진동·소음을 줄이기 위해서는 이러한 방사방향의 급격한 가진력 변화를 완화시켜야 한다. 본 논문에서 이를 완화하기 위하여 콤뮤테이션 구간동안 단방향 단락된 보상권선을 갖는SRM에 2단계 소호전압제어를 행하므로서 진동·소음을 저감할 수 있는 방법을 사용하였으며 시작기에 대한 실험을 통하여 제시한 방법이 진동·소음저감에 효과가 있음을 입증하였다. All so SRM drive has many advantage, it is generated with larger vibration and acoustic noise then those of conventional motor. The main vibration and acoustic noise source of SRM drive is generated by rapidly variation of radial force when phase winding current is extinguished for communtatio action. In order to reduction vibrating force of SRM drive, the rapidly variation of raidal force is repressed firstly. The this paper suggests the vibration reduction method that SRM drive with unidirect-short compensation winding is excited by a two stage commutation method at communtation period. This reduction effect of vibration is verified with the result obtained in the test of prototype machine.

랫드에서 미생탕의 4주 반복투여독성

김태명, 류재면, 서임권, 박동선, 조정희, 장용훈, 김윤배, 황석연 충북대학교 동물의학연구소 2009 Journal of Biomedical and Translational Research Vol.10 No.1

본문참고

염화아세트산들의 해리반응에 미치는 온도와 압력의 영향

황정의,정종재,박용태,지종기,박의환 慶北大學校 物理化學硏究所 1984 硏究論文集 Vol.5 No.-

The temperature and pressure dependences of the dissociation constants of mono-, di- and tri-chloroacetic acids were studied by the conductimetry in the range of 20-35℃ and 1-2500 bars. The thermodynamic parameters ΔH, ΔS, and ΔV were evaluated from the dissociation constants. The dissociation constants were increased as the temperature and pressure was increased respectively. The pressure effects can be explained by the fact that the increase of the charges of reaction species enhances the solvation of ions and reduces the reaction volume. As the more chlorines were substituted to acetic acid, the effect of pressure on the dissociation constants was decreased because of the enhanced solvation effect. From the thermodynamic data it can be estimated that there are two types of dissociation reactions. They are an enthalpy-dominated reaction and an entropy-dominated one.

폐목질을 사용한 모르터의 물성에 관한 기초적 연구

황병준,김영주,강태경,정근호,임서형,정상진 대한건축학회 2003 대한건축학회 학술발표대회 논문집 - 계획계/구조계 Vol.23 No.2(구조계)

Recently, as the alternatives to preserve environment such as effective usage of wastes or unusable resources are drawing attentions, researches and measures for the two tasks, which are reuse of waste wood and development of eco friendly materials, are being examined and established in various fields. However, they are still insufficient. Therefore, in this study, for the efficient application of waste woods and eco-friendly effects, mortar was produced using sawdust as the waste wood and mineral material cement for combination, in order to produce inorganic boards using waste woods, which were made when sawing. This study attempted to suggest a basic material about the physical properties of mortar, which used waste woods, after examining the features of wood mixture rate, water-cement rate, congelation according to the mixture rate of the setting accelerator, specific gravity, compression intensity, and bending intensity as experiment factors.

국내 하천 퇴적물 건강성평가를 위한 Microtox 독성시험 조건확립 연구

정홍배,박정규,문성환,류태권,김소정,배철한,황인영 한국환경독성학회 2001 환경독성보건학회지 Vol.16 No.4

1. 하천 퇴적물 공극수, 증류수 추출용액 및 유기용매 추출액을 pH6.0~6.5 범위로 조절한 후 Microtox 독성을 측정하는 것이 퇴적물내의 암모니아 독성이 배제된, 유해화학물질 오염에 의한 퇴적물 독성을 평가하는 방안임을 확인하였다. 2. 퇴적물에 대해 공극수, 증류수 추출물, 유기용매 추출물 구분하여 Microtox 독성을 구하는 것이 퇴적물 내 유해화학물질의 독성발현 특성을 예측할 수 있는 기법이라고 사료된다. 3. 조사정점 내 시료 채취 지점간 독성에 편차로 인하여, 동일 정점의 반경 50~100m 내에서 최소 4지점 이상의 퇴적물을 확보하는 것이 해당 정점의 독성 대표값을 산출할 수 있는 방안이 된다고 판단된다. 4. 한강수계인 남한강 지천인 복하천과 양화천, 금강수계인 청주 미호천, 대전 갑천, 낙동강수계인 대구 금호강, 영산강수계인 황룡강 그리고 익산 만경강을 대상으로 한 예비 조사한 결과, 집중연구대상 하천으로의 조건은 금호강이 가장 우수하였다. 5. 하천 퇴적물의 증류수 추출액과 유기용매 추출액의 Microtox 독성값 간의 상호 상관성이 높았다. 그러나, 농축 과정이 용이하므로 정점간 비교를 위한 독성 측정시 유기용매 추출액을 사용하는 것이 바람직하다고 사료되었다. Six rivers were selected as preliminary screening sites to determine the test conditions of Microtox in assessing the toxicity of the sediment. In addition, a pH range of 6.0--6.5 was established in testing pore water, aqueous extracts and organic extracts. Each extractable fraction of sediment showed different toxicities. Therefore, in order to properly examine the toxicity in the sediment, all extractable fractions of sediment samples needed to be tested with Microtox. Thus, sediment samples were additionally collected from at least 4 secondary sites within 50~100 m area of the primary sampling site to reduce any variation or deviation in toxicity assessment. From all sediment toxicity data that was collected from this study, it was concluded that the Keumho river was the most polluted with the highest sediment toxicity of all the rivers analyzed and needed further detailed research on its pollution problem.

축구선수의 Detraining과 Retraining이 혈청지질 및 호르몬농도에 미치는 영향

정정화,박재현,채종훈,성혜련,황지인,윤미숙,노금선,윤종관,윤영학,노순덕,정경숙,박일규,김은희,박현태,박상갑 대한스포츠의학회 1999 대한스포츠의학회지 Vol.17 No.1

The purpose of this study was to investigate the effects of detraining and retraining on serum lipid and hormones in soccer players. Subjects were seven male high-school soccer players. V˙O_2max was determined for each subjects by administering a treadmill test(initial speed: 90m/min, grade: 5%, increasing speed per 3 min: 30m/min). Serum lipid(T-C, TG, HDL-C LDL-C) and hormones(epinephrine, norepinephrine, growth hormones, cortisol) were assayed pre and post detraining in 10, 20, 30 days after retraining. The repeated ANOVA was used to determine significant differences. The 0.05 level of significance was as critical level for the study. The results of the study were as follows: 1. V˙O_2max(ml/min) were 3576.3±204.2ml/min pre detraining, 3234.1±198.9 ml/min post detraining. There are significant(p<.05) difference between pre and post detraining. In 10, 20, 30 days after retraining, V˙O_2max(ml/min) were 3601.4±170.9 ml/min. There were significantly(p<.05) increased in retraining periods. 2. V˙O_2max(ml/kg/min) were significantly(p<.05) decreased from 62.3±2.9 ml/kg/min to 55.9±4.7 ml/kg/min in detraining. In 10, 20, 30 days after retraining, V˙O_2max(ml/kg/min) were 62.4±3.4ml/kg/min, 62.7±2.3ml.kg/min, 67.3±7.2ml/kg/min respectively. There were significantly(p<.05) increased in retraining periods. 3. T-C were significantly (p<.05) increased from 166.6±8.5mg/dl to 175.3±10.3 mg/dl in detraining. In 10, 20, 30 days after retraining, T-C were 160.1± 3.2mg/dl, 156.7±3.7mg/dl, 140.3±9.0mg/dl. There were significantly(p<.05) decreased in retraining periods. 4. HDL-C were 61.4±6.6mg/di pre detraining, 5.3±6.6mg/dl post detraining. There are significant(p<.05) difference between pre and post detraining. In 10, 20, 30 days after retraining, HDL-C were 56.9±7.1mg/dl, 56.4±9.2mg/dl, 57.7±9.1mg/dl respectively. There were no significant difference in retraining periods. 5. The hormones(epinephrine. norepinephrine, growth hormone, cortisol) were changed as same patterns. Epinephrine were 26.0±7.0[g/ml pre detraining, 24.6±3.2pg/ml post detraining. In 10, 20, 30 days after retraining, epinephrine were 26.9±5.6pg/ml, 30.6±6.2pg/ml, 29.4±5.6pg/ml respectively. There were no significant difference in retraining periods. In conclusion, HDL-C, epinephrine, norepinephrine, growth hormone and cortisol were decreased, T-C, LDL-C and TG were increased in detraining. But HDL-C, epinephrine, norepinephrine, growth hormone and cortisol were increased, T-C, LDL-C and TG were decreased in retraining.