압력용기의 설계기준 및 손상 평가

오환섭,정효진,박상필,손두익 한국공작기계학회 2005 한국공작기계학회 춘계학술대회논문집 Vol.2005 No.-

The damage of the pressure courage by degradation can become the reason of unexpected break down or failure accident and it is very important because safety accident, the production loss, environmental pollution, social problems are occur. Consequently The result to investigat of failure accident for domestic pressure vessel, the factor of degradation is SCC, Sorrosion, Cavity, Crack

女高生의 營養知識과 食習慣 및 健康狀態에 관한 硏究

오금향,정낙원,이효지 漢陽大學校 韓國生活科學硏究所 1994 韓國 生活 科學 硏究 Vol.- No.12

The diet has held weight in the basic life of the mankind. Its contents, closely connected with the state of health, play an important role in the physical and mental happiness in life. Especially, the youth at the age of 13 to 19, who show the rapid growth physically, mentally, and psychologically, must acquire nutrition knowledge and form the right diet habits. This research shows how these knowlege and diet habit have an effect on student's health. The following results, gained by means of SPSS/pc+, were analyzed in terms of frequency, percentage, dispersion analysis, X2- test, and pearson's correlation. The results are as follows : 1.The group was made up of the humanity group of 37.2% and the natural group of 34.3% and the vocational group of 28.5%, 48.1% of the subjects for research was at the age of 16. The distribution of their scholastic marks were 26.9% in the upper level 30.2% in the middle level. and 191.% the lower level. 2.In the parents' school carrer of the object students, persons who graduated high school were numerous. The mothers' educational level was than that of the fathers. In the parents' job, fathers engaged in office were 24.0% most of the students' mothers were home makers (53.6%), and mothers engaged in official work were 13.7%. 3.The students took up 61% who answered that knew about nutrition to some degree. Most students responded that they got knowledge and information about nutrition(83.2%). The source which students acquired nutrition knowledge from were schools (48.7%) and mass communication(30%). 4.The frequency of meals in a day, was usually three times. The meal that students were likely to have was breakfast, lunch, and dinner in its order. In most cases, The students skip meals three or four times a week. The meal that students enjoyed was lunch, which was taken regularly where as they had breakfast and dinner irregularly. The reason was that they had no time to eat. After dinner, the students sometimes ate refreshments(64.3%) and it took them tenor twenty minutes to have it. They tended to talk with each other while eating. The students thought that the trouble they're having was manintaining the regular diet habit. 5.The students were in good health, and 74.3% of them had never suffered from any illness, In terms of the physical fidelity its distribution was composed of 「da」 of 48.0% and 「ra」 of. It means that the students are in a normal condition of growth. and 22.4% of the took a variety of medicines for improving their health sight and for treating anemia. 6.There was a meaningful difference between nutrition knowledge of the students and their physical health(P<0.05). The students who knew much about nutrition were physically healthy, and mental health was closely connected with physical health(P<0.01). The students who had a good knowledge of nutrition and a good physical health got good school records.

Enamel matrix derivative(EMDOGAIN^(R))을 이용한 상악 소구치의 자가이식 치험례

오유향,김효식,정현구,조태식,위유민,이창섭 조선대학교 구강생물학연구소 2002 Oral Biology Research (Oral Biol Res) Vol.26 No.2

The success of tooth transplantation or replantation depends on the viability of periodontal ligament in the transplanted tooth. Mechanical injury to periodontal tissues frequently results in dental root resorption and ankylosis, which leads to the failure of transplantation or replantation. Enamel matrix derivative (EMD) has been recently used to induce periodontal regeneration. In this report, we show a clinical case of EMD application in the transplantation of an inversely impacted and immature tooth. An impacted second premolar was found in the right maxilla of a 14 year-old girl. The tooth was inversely impacted and the root formation was incomplete. When transplantation was carried out. EMD was applied to the periodontal tissues of the extracted premolar. The tooth was fixed at the correct position and the clinical condition was followed for evaluation for 3 months. Radiographs after 3 months exhibited new bone formation surrounding the transplanted tooth. There were no signs of root resorption or ankylosis, and reconstruction of the bone defect area at the maxilla was also found. Short-term results from this case indicated that EMD application was effective in the transplantation of an inversely impacted and immature tooth. In adddition, EMD might contribute to obtain good healing without ankylosis. Further follow-up observations are necessary to evaluate the regenerative effects of EMD.

석탄회 펠렛의 미연탄소 연소 현상 분석

崔尙丁,李孝眞,吳明淑 弘益大學校 科學技術硏究所 2001 科學技術硏究論文集 Vol.12 No.-

As the number of coal fired power plants in the domestic power industry continues to increases, the amount of fly ash produced is also increasing, making the reutilization of fly ash a vital issue. Various methods to reutilize the fly ash from coal power plants have been investigated, and one of such areas with the potential to grow is the usage as light weight sintered construction materials. Sintered fly ash aggregates are produced in two steps; the first is the pellet formation step, during which the fly ash particles containing unburnt carbons were made into a pellet using caking components, and the second the pellet sintering by the combustion heat of the carbons. During the sintering process, the combustion rate of the carbon affects the characteristics of sintered pellets. The combustion of carbon occurs via adsorption of O₂ on the active sites, and desorption of CO/CO₂. The parameters which affect the rate of adsorption, desorption, and transfer of O₂ and CO/CO₂ include the O₂ partial pressure and flow rate, the pellet size, the porosity, the pore tortuosity, the pore size distribution, the carbon content and distribution. This study investigated the combustion of carbon during the production of sintered fly ash through modeling. A simple combustion model using Langmuir isotherm is used to calculate the pellet temperature. The oxygen diffusion through the pores is ignored. At the temperatures of sintering, the desoption process is a rate limiting process, making the overall rate sensitive to the desoption kinetic parameters. In addition, it was found that the carbon content and the heat capacity of the pellet affected both the rate of the reaction and the final pellet temperature, while the area of active sites only affect the reaction rate. The future work will include the combustion modeling with external and internal diffusion of O₂, and the model confirmation through experimentation.

비글개에서 신원방우황청심원의 급성 및 아급성독성시험

성하정,권오경,방명주,곽형일,이진영,신대희,박대규,정규혁,윤효인,조명행 성균관대학교 약학연구소 1998 成均藥硏論文集 Vol.10 No.1

Single and 4 weeks oral administration of New wonbangwoohwangchungsimwon (NSCH) which was used l-muscone as substitutive material of musk, to beagle dogs of both sexes were performed to investigate both acute and subacute toxicity. Beagle dogs (3 males and 3 females) in acute experiments were administered orally with sinlge dose of 2,000 ㎎/㎏ and groups of 9 male and 9 female beagle dogs in subacute experiments were given daily different dosage of NSCH, 160 ㎎/㎏/day (low dosage group), 400 ㎎/㎏/day (middle dosage group), 1,000 ㎎/㎏/day (high dosage group) once a day for 4 weeks by oral route according to the Established Regulation of Korea Food and Drug Administration (1996. 4. 16). LD_50 value for beagle dogs was more than 2,000 ㎎/㎏ per oral for both male and females. In animals administered with NSCH, there were neither dead animals nor significant changes of body weights. In addition, no differences were found between control and treated groups in clinical sign, urinalysis, eye examination, hematology, serum chemistry, organ weight and other fingings. No histological lesions were observed in both control and treatment groups. Above data strongly suggset that NSCH in beagle dogs is considered to be safe.

飮食物쓰레기의 效率的 管理를 위한 物理的 特性 및 處理

권효정,정영헌,김임경,심언봉,오광중 부산대학교 환경문제연구소 2003 環境硏究報 Vol.21 No.-

This study was conducted to manage food wastes in Korea efficiently. We carried out an experiments on food wastes generated from Yeonjae gu, Pusan as a representative boundary according to the measurement of apparent density, generation quantity, physical characteristics, proximate analysis, and elemental analysis as well as drying and carbonizing, and also tested the hazardous materials in fertilizer and compost from public and private recycling center in operation. The purposes of this study are to investigate current status of food wastes recycling methods and facilities, to examine the fuelization of food wastes, and to suggest the cost effective food wastes treatment plans. Based on the results of the analysis of apparent density and water content in food wastes, it was revealed that the apparent density of food wastes was in inverse proportion to the water content. The water content of food wastes was highly influenced by the fruit and vegetables such as watermelons. These results indicate that the food wastes with about 75 ~80wt% initial moisture content should be reduced under 70wt% moisture content by drying process pier to throwing away. Comparing the heating values of the food wastes which were calculated by Dulong's equation and Steuer's equation it was revealed that Steuer's equation(HHV 5,186 kcal/kg, LHV 880 kcal/kg) was more compatible than Dulong's equation(HHV 4,676 kcal/kg, LHV 330 kcal/kg) because the results of proximate analysis for the food wastes were very similar to those of sewage sludges. Additionally, to reduce water contents of food wastes under 60wt% as acceptable water contents for fuelization, it was also found that blending with 25wt% chars made from food wastes was more efficient than the drying of food wastes itself at 105°C, 45minutes in view of completion time. Furthermore, these chars generated from food wastes (about LHV 6,608 kcal/kg) comparable to commercial charcoal(LHV 7,134 kcal/kg) generated from oak trees and lower ash contents(under 15wt% of chars) than those.

창의적 문제해결력 신장을 위한 수학교육과정개발 : 개념적 지식을 중심으로 Theme-Based Reconstruction of Conceptual Knowledge

김정효,권오남 이화여자대학교 교과교육연구소 1999 교과교육학연구 Vol.3 No.2

본 연구는 창의적 문제해결 신장을 위한 수학 교육과정을 재구성하기 위한 구성체제의 개발과 그에 따른 개념적 지식의 재구성에 목적을 둔다. 개발되어진 교육과정의 틀은 개념적 지식과 절차적 지식을 이원화하여 개념간의 연결을 도모하는 한편 절차적 지식의 한 요소로서 사고력을 강조하여 교육과정에서 사고력변인의 주요성을 가시화하였다는 특징을 가진다. 특히 개념적 지식은 수학의 본질적 요소와 관련한 연결주제를 선정하여 이를 중심으로 개념간의 관계에 대한 이해를 도모함으로써 수학이란 학문의 지식구조에 대한 깊은 이해를 가지도록 하였다. 이는 수학적 문제사태에서 학습자가 확산적 사고와 비판적 사고에서 사용할 수 있는 지식기반을 풍부히 가질 수 있도록 하기 위함이었다. 개발되어진 수학교육과정틀을 통해 구체적인 초등교육과정을 제시하였는데 이는 정보화사회에서 요구되는 창의적인 문제해결력을 교육하기 위한 체계적이고 실질적인 초등 수준의 수학교육과정이 될 수 있을 것으로 기대된다. This study is a part of a research to develop the elementary mathematics curriculum to enhance creative problem-solving abilities through reconstructing and specifying national mathematics curriculum. The developed mathematics curriculum is characterized as division of conceptual knowledge and procedural knowledge, and emphasis on relationship among concepts. The explicit network among concepts and between concepts and skills in the curriculum can help children have a powerful knowledge base for divergent and critical thinking in mathematical problem solving. for the relationship among mathematical concepts, the conceptual knowledge is reconstructed on the four themes, such as algorithm, relationship, pattern and generalization, and representation, which stems from the nature of mathematics. The results of reconstruction are presented in the form of matrix, such that the vertical axis represents how the concepts within each strand of mathematics curriculum are unified, while the horizontal axis shows how the concepts across the strands are related in terms of the themes.

고령 장애인의 일(WORK) 경험과 욕구에 관한 연구 : 뇌병변 장애를 중심으로

이효성,김근아,김태연,오정은 한국장애인고용촉진공단 고용개발원 2007 장애와 고용 Vol.17 No.2

본 연구의 목적은 고령이면서 장애를 동시에 경험하고 있는 고령 장애인들의 일 경험과 욕구에 관한 특성을 당사자의 관점에서 이해하는 것이다. 이러한 목적을 달성하기 위해 50세 이상 뇌병변장애인 13명을 대상으로 일 경험과 욕구에 관한 개방형식의 질문으로 심층 인터뷰를 실시하여 그 결과를 분석함으로써 고령 장애인 당사자의 일 경험과 욕구에 대한 심층적 이해와 현상의 의미를 깊이 있게 파악하고자 하였다. 분석결과, 고령 뇌병변장애인들은 일을 하고자 하는 높은 욕구를 가지고 있으며 일을 통해 삶의 의미와 보람을 찾고자 하나 현실적으로는 장애와 고령, 그리고 만성질환자라는 삼중고 속에서 “일하기” 에 상당한 제약을 받는 것으로 나타났다. 이러한 연구결과는 지금까지 고용정책에서 소외되었던 고령 장애인의 ‘일’ 에 관한 정책적 개입의 필요성을 강력하게 시사해 주고 있다. The purpose of this study is to understand the characteristics of the experiences and needs for work of aged people with disabilities who experience both old age and disability from their viewpoint. To this end, this study conducted in-depth interviews with 13 people aged 50 or older with encephalopathic disabilities by open-ended questions regarding their experiences and needs for work, and analyzed the results so as to more deeply understand the experiences and needs for work of aged people with disabilities as well as the implications of the present situation. The analysis results showed that aged people with disabilities have high needs for work and try to find the meaning and worth of life through work, but in reality face considerable limitations to ‘working’ in the triple handicaps of disability, old age, and chronic disease. The results of this study strongly suggest the need for policy intervention in the ‘work’ of aged people with disabilities who have been neglected by employment policies until now.

국산 회중석을 이용한 타이어용 Ice-Spike 제조에 대한 연구

李正根,吳平濟,朴冕用,李應孝,金永基 건국대학교 1972 學術誌 Vol.14 No.1

Tungsten carbides are produced by carburization of tungsten powder and the reduction of ammonium para-tungstate obtained from Korean scheelite. The ice-spike for the automobile tire are made from tungsten carbide mi ed with cobalt powder into various amounts through the process of the double sintering, and the product composed of tungsten carbide 95.5% and cobalt 4.5% is superior to all others. The various physical properties and fabricating conditions far the production of cemented carbide are also discussed. This paper is the starting point of the development leading to wide introduction of the products permitting to ice-spice, cutting tools, etc. by using of Korean scheelite.

창의적 문제해결력 중심의 수학 교육과정 개발 및 적용 : 초등학교수준을 중심으로

김정효,권오남 한국수학교육학회 2000 初等 數學敎育 Vol.4 No.2

본 연구는 창의적 문제해결력 신장을 위한 수학교육과정을 개발하고, 그 적용효과를 알아보고자 하는데 목적을 둔다. 개발된 창의적 문제해결력 중진을 위한 수학교육과정은 수학의 개념적 지식(내용)과 절차적 지식(기능), 그리고 창의적 사고요소(확산적 사고와 비판적 사고) 등 3가지 요소를 기반으로 하였다. 세부적으로 보면 수학교육과정의 내용을 개념적 지식과 절차적 지식으로 이원화하여, 개념적 지식은 수학의 본질을 구성하는 4개의 주제를 중심으로 6개 하위영역을 연결하여 총괄 개념, 학년별 개념, 그리고 하위개념으로 구성하였고, 절차적 지식은 사고요소, 계산기능요소, 수학적 도구와 기술사용 등 3요소로 구성하였다. 한편 창의적 사고요소는 이러한 교육과정내용을 PBL을 기반으로 하는 단원개발을 하는 과정에서 융합되도록 하였다. 그 적용효과를 검증하기 위해서는 초등학교 5학년을 대상으로 1학기간 투입하고 수학적 창의적 문제해결력 검사를 실시하여 집단간 점수차이를 검증하였다. 그 결과 본 교육과정은 아동의 수학적 창의적 문제해결력 신장에 효과가 있는 것으로 드러났다. The purpose of this study is to develop and implement an alternative elementary mathematics curriculum to enhance creative problem solving ability. The curriculum consisting of three main elements was developed. The three elements are content knowledge, process knowledge and creative thinking skills. The curriculum contents and the units were developed by mathematics educators, elementary educators, psychologists, elementary school teachers and curriculum specialists for 3 years. In order to test the effectiveness of the developed curriculum, the 5 units based on a problem-based-learning(PBL) method were implemented in a 5th grade class as an experimental group during the second semester. For the comparison group the ordinary lesson based on the 6th national mathematics curriculum was implemented during the same period. Performance assessment was developed and used for the pre and post test. T-test was used to testify that the effect of the curriculum is statistically significant. The results of the test showed that the experimental group progressed significantly in the creative problem solving ability, but the comparison group did not.