새로 혼련한 디젤엔진오일의 내마모성에 관한 연구

姜錫春 水原大學校 1998 論文集 Vol.16 No.-

A diesel oil which was formulated at KRICT and a commercial diesel engine oil (API CG-4) made form same base oil were tested by road test and analyzed of their antiwear properties. The tested oil were sampled from engine at every 1000㎞ until 8000㎞ and analyzed the change of metal concentration by Atomic Emission Spectroscopy. From the study, new formulated oils has better antiwear property compare to the commercial oil within the test range. Also from the test of 4-ball machine, the wear scar diameter of the new formulated oil was smaller than that of the commercial oil for both new and used oil. It was found that the formulated oil could reduce the wear of lubricated parts if it is used in diesel engine within the test range.

다층원판 목재용 톱날의 저소음효과에 관한 연구

강석춘 수원대학교 산업기술연구소 2000 산업기술연구소논문집 Vol.15 No.-

To reduce the noise from the wood cutting work with circular saw at the saw mill(lumber mill) or a construction area, some multi-layer sandwich saw blades which a aluminum or copper plate was inserted between the two steel plates were developed and tested of the wood cutting noise level at various test methods. From the research, it was found that the multi-layer circular saw blade with copper or aluminum plate between steel plates and spot welded 60 points could reduce the wood cutting sound level about 8.3 dB(97.031 dB - 88.743 dB) at indoor test and 3.8 dB(84.805 - 81.638 dB) at field test.

환경친화성 오일로써 채종유에 관한 연구

강석춘 水原大學校 1999 論文集 Vol.17 No.-

As the environment problems with mineral oil being used in the most of industrial applications have became important for the industrized countries, some vegetable oils are being studied as an environmentally acceptable oil in these day. But there are some problems for vegetable oil to be used as a machine oil because of oil supply, oil properties as a lubricant for machines and biodegradability. From the study, it was found that rapeseed oil is the most promising environmentally acceptable oil among the vegetable oils. It has a good properties as for a lubricating oil and a good biodegradability, but the oxidation stability and the increase of viscosity in the oil are the problems to be improved by formulation with some additives in order to be replaced for mineral oils or synthetic oils. If the rapeseed oil is used only within a short time as a wo-cycle engines and etc, it can be a good lubricating oil enough to be used in machines having an excellent biodegradability.

나일론 실린더와 널산 강축의 열박음과 유도가열에 의한 접합의 연구

강석춘 水原大學校 2004 論文集 Vol.22 No.-

Polymers like nylon have good frictional properties to be used as machine elements materials, but its mechanical strength(tensile or compression) is inferior to steel for the mechanical elements. For the tribological application of Nylon as gears, sliding bearings, cam and etc, the steel shafts were fitted by a process of interference expansion fit and bonded by induction heating method. The joint shear strength of the two materials was measured by compression test. From the experimental test, the adhesive shear strength between these two materials was affected by the factors of interference between nylon and steel, the size of nylon cylinder, knurling of steel shaft and inducting heating conditions. The most effective jointing conditions and methods were analyzed and decided for the practical application in the machinery industry.

새로 혼련한 디젤엔진오일의 실차시험에서 오일의 물리적, 화학적 변화에 관한 연구

姜錫春 水原大學校 1997 論文集 Vol.15 No.-

A diesel engine oil which was formulated at KRICT and a commercial diesel engine oil(API CG-4) made from same base oil were tested by car and analyzed of their physical, chemical properties. The tested oil to be analyzed were sampled from engine every 1000km until 8000km and analyzed the change of kinematic viscosity, TAN, TBN, IR analysis. From the research, both the tested oils were almost same properties for the change of TAN and TBN, but the change of viscosity of formulated oil was slightly higher than that of commercial oil. Also for the commercial oil, the deflection factor of the Zn-DTP which was added as a antiwear property was not change any more after 7000km. But the formulated oil was change continuously until 8000km, which mean that the ability of wear protection of the sliding pairs exists for the formulated oil. With the results which were analyzed of the properties of oils by field test, it was found that the commercial oil could be used only within 7000km, but the formulation oil can use more than 8000km without severe wear of the sliding parts in the diesel engine.

왁스(wax)함침형 나일론6의 합성과 그의 기계적 성질에 관한 연구

강석춘(Suck Choon Kang),정대원(Dae-won Chung) 한국자동차공학회 1999 한국 자동차공학회논문집 Vol.7 No.7

저소음 목재용 회전톱날의 개발에 관한 연구

강석춘(Suck-choon Kang) Korean Society for Precision Engineering 2000 한국정밀공학회지 Vol.17 No.7

오일 함침에 의한 흑연/나일론 복합체의 마찰특성 향상에 관한 연구

강석춘(Suck-choon Kang),정대원(Dae-won Chung) Korean Society for Precision Engineering 2002 한국정밀공학회지 Vol.19 No.3

실험적 중대뇌동맥 폐쇄로 인한 급성 뇌경색에 대한 Thiopental 효과

강준기,김문찬,윤석훈,허춘웅,송진언,김선무 대한신경외과학회 1981 Journal of Korean neurosurgical society Vol.10 No.1

An experimental ischemic model in cats is described in which we have attempted to produce acute cerebral ischemia by occlusion of the middle cerebral artery (MCA) through the orbit. The main objectives of this experiment were: to observe the effect of thiopental in the tophographic distribution of infarct; the size of the infarct; histological changes of ischemic nerve ceils following occlusion of a major cerebral artery; to investigate the best timing of the administration and dosage of thiopental after the occlusion. 80 adult cats weighing 2.7 to 4.0kg, were used in this study. The components of the pathophysiological responses, systemic changes, cerebral infarct size and histopathological ischemic neuronal changes were studied in these groups of animals. We observed the permanent effect of the thiopental on acute focal cerebral ischemia in 40 cats by effecting permanent occlusion of MCA. The EEG was monitored continously using bifrontal electrodes from the time of administration of thiopental (10mg/kg). The animals were divided into 4 groups of 20 cats each. The 4 different groups were used to investgate the effects of thiopental on focal ischemia according to different time interval. The time intervals were 6hours, 24hours, 48hours, and 72hours after occlusion of MCA. Each animal group were divided into two groups, which one was control (n=10) the other, thiopental treated group (n=10). The results obtained were as follows: 1) Blood gases, artrial pressure, body temperature, and intracranial preosure differed among groups only a s fllows: (a) Normal blood pressure was maintained but pulse rate was slightly fast in each control group. (b) Blood pressure and pulse rate in the thiopental treated groups were significantly lower than in the control groups. In the thiopental treated groups, the value of PaO₂ was significantly higher than control groups, however, PaCO₂, was not significantly higher in the thiopental treated groups as compared to the control group. 2) In the control groups, severe contralateral hemiplegia (grade Ⅲ) developed in the early stage of MCA occlusion, however the neurological deficit progressively improved to the state of abnormal climbing (neurological grade Ⅱ) 48 hours to 72 hours after the occlusion. In the thiopental treated groups, minimum to mild neurological deficit significantly developed in the early stage of MCA occlusion and in one case walking ability was regained. 3) The size and distribution of the infarct significantly decreased to 60% in the thiopental treated groups (P<0.01). The vale of the size of the size of the infarct in the thiopental treated groups 72hours after occlusion was minimized to 0.3±0.6% (P<0. 01). In 80 percent of the control group cases severe extensive ischemic neuronal damage (score 3 or 4), was observed, 70 percent in the thiopental treated groups showed mild ischemic nerve cell changes (score 1 or 2) when the histological examination was given. Although the severity of the ischemic neuronal damage was gradually improved from 6 hours to 72 hours after occlusion of the MCA in the control, the thiopental treated group was not significantly affected to the time factor. 4) Significant reduction of experimentally induced acute focal cerebral ischemia was associated in the cat model with the administration of thiopental at 5 minute, 30 minute. and one hour postocclusion. Also we have defined the best barbiturate, best does, and best timing of administration to protect the acute focal ischemia.

나일론의 윤활제 함침에 따른 마찰 및 마모특성

강석춘 水原大學校 2001 論文集 Vol.19 No.-

In order to make a new dry-friction engineering material, lubricant-impregnated cast nylons were synthesized by anionic polymerization of ε-caprolactam in the presence of mineral oil, wax, graphite and MoS2. Nylons impregnated with 0% to 8% lubricant content were synthesized and the frictional properties as well as other mechanical properties were tested. the tensile strength of the lubricant-impregnated nylons were decreased a little for all lubricants. However, elongation and impact strength of the oil and wax-impregnated nylons were decreased as content of lubricant was increased, on the other hand, the nylons impregnated with graphite was increased for both of the properties. The lubricant-impregnated cast nylon with oil and wax content of 8% showed the smallest friction coefficient and 1/2 of the lubricant-free nylon, while no significant decrease in friction coefficient was observed for the nylon with graphite and MoS2. At the wide range of impregnation of lubricant, all the wear rate of nylon with 4% and more oil and wax contents were 10% smaller than that of the lubricant-free nylon.