플라즈마용사 TiO₂코팅 강재의 음향방출 특성

김귀식,박경석,홍용의 제주대학교 산업기술연구소 1999 尖端技術硏究所論文集 Vol.10 No.2

In this paper, adhesiveness of plasma thermal sprayed coating steels is investigated through AE(acoustic emission) in loading a tensile. AE parameters used are event, count, energy and peak amplitude. The powders used for the coating are nickel aluminum composite powder Ni-4.5wt.%Al (BOND ) and titanium dioxide powder TiO2 (TOP). Test specimens are BOND, TOP and BT(BOND + TOP) that are sprayed on carbon steel(S45C) by plasma thermal spray. In the tensile testing, the process and occurrence of the exfoliation of the sprayed coating layer can be estimated by AE. Characteristics of AE parameters, such as event, count, amplitude and energy, on the layer exfoliation have all the similar aspects. The exfoliation of BOND specimen occurs from 16% tensile strain to fracture point, TOP specimen does from 1% to 5%, and BT specimen does from 6% to 11%.

제주도 하수처리장 방류수를 이용한 소수력 발전에 대한 연구

김귀식,문일성 제주대학교 공과대학 첨단기술연구소 2007 尖端技術硏究所論文集 Vol.18 No.-

This study is to investigate the micro hydropower by discharge water of Jeju sewage treatment plant located in Jeju city and Dongbu sewage treatment plant located in Seogwipo city, Jejudo. The flow rate is applied at 1.11m³/sec in Jeju and 0.157m³/sec in Dongbu, which are the average 95 day flow rated for the recent 3 years. The net head is 5.21m in Jeju and 12.41m in Dongbu which are hight between discharge flow chamber and the location of hydraulic turbine installation. Therefore, the quantitiy of electric of power generation is estimated to be 42.97kW in Jeju and 14.6kW in Dongbu. The monthly quantity of electric generation is 28.23MW in Jeju and 9.46MW in Dongbu. Also the yearly quantity of electric generation is 338.7MW in Jeju and 113.53MW in Dongbu. The type of hydraulic turbine recommends a crossflow or a tubular in Jeju and an inline-type hydraulic turbine in Dongbu.

淡水魚의 carotenoid 色素에 關한 硏究

金貴植 여수대학교 1989 論文集 Vol.3 No.-

The compositions of carotenoid in the integuments and fins of Liobagrus mediadiposalis MORI and Psedobagrus sp. were compared through the thin layer chromatography, column chromatography and visible absorption spectrometry. The total amount of carotenoid in the integuments and fins of Red catfish was 1.6 mg% and that of cutlailed bullhead was 0.8 mg% less than that of catfish. The carotenoid of Red catfish was composed of zeaxanthin, lutein, cynthiaxanthin, β-carotene, triol and cryptoxanthin with the percentages of them being 57.7%, 21.8%, 3.4%, 1.2%, 1.1%, 0.8%, respectively. The carotenoid of cutlailed bullhead was composed of zeaxanthin, lutein, β-carotene, cryptoxanthin, cynthiaxanthin and triol with the percentages of them being 44.5%, 19.1%, 9.5%, 9.1%, 6.4%, 3.2%, respectiyely. The cartenoid compositions in integuments and fins of catfish and cutlailed bullhead, both of which belong to the same Family Bagridae, were found to be composed of the same constituents, but with the ratio of them being different.

海洋構造物用 알미늄合金의 應力腐飾龜裂에 의한 破壞硏究(Ⅰ)

金貴植 제주대학교 1983 논문집 Vol.15 No.-

高力 耐蝕性 알미늄合金(5052)의 應力腐蝕龜裂에 의한 파괴거동을 硏究 檢討한 結果를 要約하면 다음과 같다. 1. K₁-V거동에서 5052Al합금은 他 高力A1合金과 같이 Region I과 II만이 調査되었다. 2. 耐力이하의 靜荷重일지라도 環境과 組合하여 材料의 波勞를 가져오면 crack成長速度는 동일한 K₁하에서 훨씬 크다. 3. crack成長速度가 10??m/s일 때 K₁scc은 ~58kg/㎣?²이다. 4. K₁의 증가에 따라 破壞時까지 부식전위의 변화는 0.061 V였다. The test specimen, designated the precantilever beam, was employed for a fracture mechanics study of stress corrosion cracking(SCC) of type 5052 Al-alloy in seawater. The effects of crack velocity and corrosion potential upon the stress intensity were investigated. The results are as follows; The stress intensity (K?scc) below which crack velocity became immeasurably was about 58㎏/㎣?². Above this value, region Ⅰand Ⅱ behavior was observed. The greater fatigue by corrosion circumstance and lower static stress than proof stress is, the larger becomes crack velocity. And corrosion potential is varied 0.061 volt according to the stress intensity.

중등교육에서의 생명교육

김귀식 서강대학교 생명문화연구원 1994 생명연구 Vol.2 No.-

Education cannot be done without relation to the situation of the age and its society. Education should make a contribution to the improvement of the age and its society for their higher level. Education also should play a role to relieve the society from a serious problem as it happened. Nowadays, modern education came to meet a task ; how we will solve the problem of environmental pollution and the tendency to make little of life as human beings' common tasks. Especially it is a pity that the education of Korea has not been giving actual attention to the problems of environment and life, because of the emphasis of entrance examination for college, and so we have to try to get over this sooner or later. Education at school is caught in intellectualism, functionalism, and standardization. So this doesn't seem to educate a view of the world for life all the human race. Education in Korea doesn'ㅅ have proper curriculums to be able to educate environment and life more synthetically and more systematically and, although teachers should realize the improtance of education about these, they are still almost indifferent to their sense of duty about them. Most of all, it may by that there is no supporting system of administration equipped at all. From the Ministry of Education to the classroom of the school, environmental education, most be treated as the most important task of modern society to be carried out though the systematic and consistent structure of administration. However, environmental education is necessary in modern education, and it must be not simple campaign for environment but the approach to more basic problems. It is just the matter of the matter of the value of life but also only make students know the essence and value of life but also have the proper view of life. Modern education, with the existence of the human beings threatened by the pollution and destruction of environment, will have to do its best to change the Microcosmic view of life into the Macrocosmic. This, as the environmental movement, the human movement and the life movement to change man, means that nature and man are the one and only creature of an organism, and that the universe is a unified body, and so we must understand it, and then put it into practice in our daily life. If only so, for what can man destroy nature and discharge a large quantities of pollutant? Education to change man, this is just the beginning of life education, and the core of education. Especially in our country. Korea, we can very often find many obstaeles of education, undemocratic education system and the evil laws of education anywhere. Therefore, we will have to improve the educational condition of anti-life like these. Now ecocide is going on. It is that cultural ecocide is being done. Cultural ecology means the diversity of culture. It depends on education with discussion. But there is no education discussion at school. With these chain reaction, cultural ecology is taken ill(A Standardized Culture), natural ecology does so(A Phenomenon of Species Reduction) and at last man and nature are passing away together. At school, life education is very urgent like this.

문학교사의 정체성 : 나의 문학교사상

김귀식 한국문학교육학회 1999 문학교육학 Vol.4 No.-

아연피복강재의 부식피로 균열성장특성

김귀식,현창해,현경수,오맹종 濟州大學校 産業技術硏究所 1996 산업기술연구소논문집 Vol.7 No.1

Corrosion fatigue crack growth behaviors of Zinc coating steel, SGH41, in 3% NaCl aqueous solution was investiged with a hydraulic fatigue testing machine. A hydraulic fatigue test machine was manufactured using a personal computer, a proportional valve one, a hydraulic system. Corrosion fatigue crack growth rates of SGH41 is reduced than that of the uncoated steel by anti-corrosion effect of zinc. Pans rule, da/dN=C(ΔK)^(m) is applied about the relation between the stress intensity factor range, ΔK, and crack growth rate, da/dN, of both the coated specimen and the uncoated one. Where the slope of the correlation, m, is 2.24 for the coated specimen and 3.66 for the uncoated one. The corrosion sensitivity, (da/dN)_(corr)/(da/dN)_(air), of the coated specimen was smaller than that of the uncoated specimen.

화염용사에 의한 TiO₂코팅재의 마모특성

김귀식 濟州大學校 工科大學 産業技術硏究所 1998 尖端技術硏究所論文集 Vol.9 No.2

This paper is to investigate the wear behaviors of a thermal sprayed TiO₂coating film by a pin-on-disk type wear testing machine. The test specimens were to flame sprayed TiO₂ coating on carbon steel substrate(S45C) with Ni-4.5%Al alloy bond coating. Wear characteristics, which were friction force and friction coefficient. and wear rates, according to friction conditions were conducted on the three kinds of load at room temperature. The friction coefficient and wear amount of the TiO₂coating were remarkably decreased than those of substrates in the dry and the lubrication condition. As increasing the load, the wear effects of the TiO₂ coating in lubrication environment were decreased by the abrasion wear.

해양환경중에서 각종 고장력강의 부식피로 수명예측

金貴植 제주대학교 1993 논문집 Vol.36 No.-

해양기계 및 구조물용으로 보급 개발되고 있는 각종 고장력강(HT50, HT50-TMCP, HT80)의 실험실내 해수중 부식피로시험으로 부터 구해지는 부식피트의 성장칙, 부식피트로부터 균열이 발생하는 한계조건 ?? , 부식피로균열 성장속도(da/dN)와 수정유효응력확대계수폭( ?? )의 관계로 부터 장시간 부식피로 수명예측방법을 제안하고 방법에 의하여 구해진 예측수명은 실험결과와 잘 일치하였다. Prediction method of long-term corrosion fatigue life for high-tensile strength steels in synthetic seawater were proposed. They were obtained from corrosion fatigue process composed of three stages, namely, corrosion pit growth, transition into crack from the corrosion pit, and corrosion fatigue crack growth. The corrosion pit depth was found to increase with time t following the relation : corrosion pit depth ∝ ?? . The condition of transition into crack from the corrosion pit was determined by stress intensity factor, by assuming the corrosion pit as a sharp crack. The crack growth rates were obtained based upon a linear summation method in terms of modified effective stress intensity factor range, which eliminates the corrosion prodects-induced wedge effect. The predicted results agreed well also with experimental results.

플라즈마 용사 TiO_(2)코팅 강재의 마찰속도 변화에 따른 마모특성

김귀식,김성익,김희곤 濟州大學校 産業技術硏究所 1999 산업기술연구소논문집 Vol.10 No.2

In this paper, wear behaviors of plasma sprayed ceramic coating steels have been investigated experimentally through the friction coefficient, friction force and weight loss. In wear behaviar of substrate(S45C) and TiO_(2) coating specimen in dry friction , the friction coefficient is monotonous according to increase the friction velocity. The amount of weight loss increase when the load is high. The wear and friction in lubrication doesn't occur almostly because of the lubrication property. The wear of stator. SUJ Il pin. is small in S_(4)5C. and large in TiO_(2). The adhesiveness of TiO_(2) wear in lubrication is larger than that in air. so the lubrication is important to the low wear of the tribology.