• 한국소성가공학회:학술대회논문집
• /
• 한국소성가공학회 1999년도 춘계학술대회논문집
• /
• pp.94-97
• /
• 1999

The study has been performed for the relation between die and product in closed die upsetting by the experiment. the strain of die has been given by the simple experiment using the strain gauge located at the outer surface of die and the deformation history of die and product has been given by the experiment and Lame's formula. the product with accurate dimension and shape can be obtained by analysing elastic deformation of die during upsetting process. The deformation of die during metal forming process has been given by the experiment and lame's formula. The product with accurate dimension and shape can be obtained by analysing elastic deformation of die during upsetting process. The deformation of die during metal forming process has been usually predicted by the experience of industrial engineers of finite element analysis. But it is difficult to predict the dimension of product at unloading and ejected states. The study has given useful result for the deformation history of die and product through the experiment and Lame's formula at closed die upsetting and can be applied in the die design for product with accurate dimension.

• Mass Spectrometry Letters
• /
• 제13권4호
• /
• pp.133-138
• /
• 2022

Taurine is a type of sulfur-containing amino acid having a sulfate functional group, that is biosynthesized from cysteine. It is mainly distributed in high concentrations in animal tissues and is known to have various effects such as osmotic pressure control, calcium control, anti-inflammatory, antioxidant, and hepatocellular protection. Also, taurine deficiency causes a variety of symptoms, including visual impairment. In particular, in the case of cats, taurine is not biosynthesized and must be supplied through food, so it is classified as an essential amino acid. In this study, an analysis method using mass spectrometry was developed instead of the commonly used derivatization method to quickly, environmentally, and precisely analyze taurine in various animal feeds. The developed analytical method showed good linearity (R² > 0.99), accuracy (81.97-105.78%), and precision (0.07-12.37%). In addition, the developed method was further verified through quantitative comparison with the derivatization method. This developed method was used in the determination of taurine in 20 animal feed samples obtained from South Korea. The levels of taurine found ranged from 81.53 to 6,743.53 mg/kg. The developed analysis method will be used for the detection and quantification of taurine in domestic feed.

• 한국과학교육학회지
• /
• 제27권1호
• /
• pp.59-69
• /
• 2007

이 연구에서는 과학실험의 새로운 방법으로 학교현장에서 도입 단계에 있는 컴퓨터를 기반으로 하는 MBL실험에 대하여 초 중 고 교사들의 인식을 조사하였다. 이를 위해 초 중 고등학교의 과학교과서에 나오는 실험 주제 중 MBL(microcomputer based laboratory) 실험으로 대체할 수 있는 실험주제를 세 가지씩 선정 하여 초 중 고등학교 과학 교사들에게 연수를 실시한 후 MBL실험 연수 내용 MBL실험기대효과 연수 후 MBL실험 적용 의지에 대하여 설문조사를 실시하였다 연구 결과, 초 중 고등학교 교사 모두 MBL실험 연수가 매우 유익하고 유용하다고 생각하였으나 연수내용 수준에 대하여 약간 높게 생각하였다. 또한 MBL실험에 대한 기대효과로는 컴퓨터를 이용하는 MBL실험은 정확하고 빠르게 데이터를 수집하고 처리 할 수 있어 실험 시간을 단축할 수 있으며, 단축된 실험시간을 실험결과를 분석하고 토론하는 활동에 활용할 수 있어서 올바른 개념 형성과 그래프 해석 능력 및 탐구력 신장에 효과적일 것이라고 생각하였다. 그러나 실험기구 조작 능력 향상에는 효과적이라고 생각하지 않았다. 또한 대부분의 교사들은 연수 후에 과학실험 수업에 바로 이용하려는 의지가 높게 나타났으나, 새로운 교육과정에 도입하기 위해서는 MBL실험을 위한 도구 구입과 낙후된 실험실 여건, 교사 연수 기회 부족 등이 장애라고 지적하였다. MBL실험의 확장 적용을 위해서는 MBL실험 도구의 단가를 낮추기 위한 기술 개발 및 각종 센서의 제작 보급과 함께 MBL실험 자료 개발과 교사연수가 확대되어야 할 것이다.

• 한국안광학회지
• /
• 제7권2호
• /
• pp.73-77
• /
• 2002

컴퓨터 인터페이스 카드를 기존의 구형 PC(pentium I)에 장착하여 광을 사용하는 기초광학 실험에 적용함으로써 학생들에게 광학실험의 흥미도를 유발하고 실험의 정확도를 높일 수 있었다. 빛의 회절실험에 적용한 결과 기존의 실험경과와 비교해 실험의 정확도가 향상되었으며, 이론적인 계산치와의 비교에서도 오차범위 내에서 동일한 결과를 얻었다. 향후 광을 사용하는 기초광학 실험 전반에 활용함으로써 폐기되는 구형 PC의 활용뿐만이 아니라 수동형식의 기초광학 실험을 자동화할 수가 있어서 실험 효율성 측면에서 의미가 크다고 할 수가 있다.

• 한국약용작물학회:학술대회논문집
• /
• 한국약용작물학회 2008년도 추계학술발표회
• /
• pp.185-186
• /
• 2008

• Journal of Astronomy and Space Sciences
• /
• 제35권2호
• /
• pp.111-117
• /
• 2018

A previous exo-terrestrial life-detecting experiment, which was conducted on Mars, sought to detect the products of glucose metabolism, the most common biological process on Earth (Viking biological experiment). Today, glucose metabolism is not considered the universal process of life survival. As NASA plans to launch an orbiter mission in the near future (2020s, the Clipper) and ultimately conduct a lander mission on Europa, a detection experiment that can give broader information regarding habitability is highly required. In this study, we designed a life-detecting experiment using a more universal feature of life, the amphipathic molecular membrane, theoretically considering the environment of Europa (waterdominant environment). This designed experiment focuses on finding and profiling hydrophobic cellular membrane-like microstructures. Expected results are given by conceptual data analysis with plausible hypothetical samples.

• Toxicological Research
• /
• 제7권1호
• /
• pp.93-112
• /
• 1991

This study was carried out to investigate the various factors on induction of experimental hepatocarcinogenesis in Sprauge-Dawley rats. The experimental animals were divided into three Experiment. Experiment I, II and III were began rats with initial age of 6, 16 and 55 weeks, respectively. All Experiment were injected intrapertioneal with diethylnitrosamine (DENA` 200 mg/kg) as an intiator and group 3, 4 of Experiment I, II and III were fed on diet containing 0.02% 2-acetylaminofluorene (2-AFF) as a promoter for 6 weeks. Three weeks after two-thirds partial hepatectomy was performed in group 2, 4 of Experiment I & II and group 3 of Experiment III.

• 대한기계학회논문집
• /
• 제19권8호
• /
• pp.1810-1821
• /
• 1995

Photoelastic experiment has been used to analyze stress of structure and stress in the vicinity of crack tip etc.. Model experiment such as photoelastic experiment has been restricted by problem of residual stress in the photoelastic model material. They are generated by molding, cutting and time effects etc.. They produce some errors in the results of photoelastic experiment data. In this paper, stress optic law considering residual stress already developed by authors was applied to the stress concentration problem and fracture mechanics. Although the specimen was bad with residual stress, we could obtain good results by using the stress optic law considering residual stress. It was found that the stress optic law of photoelastic experiment could be applied to the stress analysis of bimaterial.

• 한국주거학회:학술대회논문집
• /
• 한국주거학회 2003년도 정기총회 및 추계학술대회
• /
• pp.59-65
• /
• 2003

The present article has the purpose of evaluating subjective response of Won Buddhism sanctums by psychoacoustics experiment. Furthermore, basing on this experiment, the present article makes a suggestion of a physical sound-evaluating index. To achieve the purpose, I conducted an psychoacoustics experiment at 6 sanctuaries out of the representing 40 sanctuaries of Won Buddhism sanctums, which size is bigger than 1,000 m$^3$. I made a reanalysis with 3 Buddhist sanctums out of the subjects of psychoacoustics experiment which are generally rated superior. From the result, I can make each evaluation type into two types, sound clarity and space sense of sound. Also, I make various suggestions of physical parameter, with which I can evaluate the proper sound condition for Won Buddhism sanctums.

• 한국감성과학회:학술대회논문집
• /
• 한국감성과학회 1997년도 한국감성과학회 연차학술대회논문집
• /
• pp.140-145
• /
• 1997

A stuey to investigate the perception characteristics of color and brightness was conducted in a combined PC and TV monitor, The objective of this study is to suggest user's favorite color temperature in PC mode and user's favorite contrast in TV mode. Investigated factors were monitor coating(coatiog vs. non-coation)and screen brightness (30fL vs. 35fL)in first experiment and monitor coating and pucture movement(static vs. dynamic) in second experiment. The first experiment was conducted in TV mode. Twenty-three subjects (male 12, female 11) perticipated in this experiment. In first experiment, average color temperatures were about 8000K in all experimental conditions. In addition, there was significant difference between coating and non-coating screen at 0.1 level. In second experiment, average contrasts were obtained in all esperimental conditions. There was significant difference between coating and ndn-coating screen at 0.05 level, In addition, there was significant difference between static picture and dynamic picture at 0.1 level