운동과 활성 산소ㆍ황산화물의 관계에 관한 고찰

김도준,오봉석,전형권 龍仁大學校 1999 용인대학교 논문집 Vol.17 No.-

The purpose of this study was to review for further understanding of the possible mechanisms of free radical formation during exercise and the relation of exercise and exercise induced oxidative stress and the antioxidant system. Acute or chronic strenuous exercise results in excessive production of reactive oxygen species(ROS). This ROS production may lead to lipid peroxidation and protein oxidation in the exercising muscle. Now, the results of study on the role of non-enzymatic defense system was not clear. Further study is necessary to get clear results of antioxidants. But, exercise induced oxidative stress may be reduced by antioxidant ingestion. Therefore, it is necessary to study on proper exercise for reduction of oxidative injury and for efficient practice of intensive exercise by antioxidant administration.

수소첨가에 따른 메탄-공기 예혼합기의 연소특성 (I)

김봉석,류정인 忠南大學校 産業技術硏究所 1994 산업기술연구논문집 Vol.9 No.2

In the present study, combustion characteristics of natural gas as alternative fuels for automotive vehicles were investigated at various hydrogen substitution rate and initial pressures in a closed vessel. For the purpose of executing the study, cylindrical type constant volume combustion chamber was designed and made. And, such accessory equipments as CDI ignition system, pre-mixture manufacturing system, and thermocouple were made. Also, to acquire and analyze the data related to the conbustion characteristics, we using pressure pick-up, R type thermocouple and chemiluminesence NO analyzer. The mixtures contained 0% through 50% hydrogen content by volume in methane, and initial absolute pressures were varied 1.5㎏/㎠ , 2.0㎏/㎠ and 2.5㎏/㎠, respectively.

수소첨가에 따른 메탄-공기 예혼합기의 연소특성(Ⅱ)

金俸錫,柳正人 忠南大學校 産業技術硏究所 1995 산업기술연구논문집 Vol.10 No.1

An experimental investigation of the combustion characteristics of methane-air premixtures with various hydrogen supplement rates and initial pressures was performed in a disk-shaped constant volume combustion chamber. The main results obtained from the study can be summarized as follows. The flame propagation processes of premixed methane-air are propagated with a spherical shape, but they are changed an instable elliptical shape flame with very regular cells by increasing the hydrogen supplement rate. The combustion characteristics such as volume fraction burned, flame radius and flame propagation speed are increased by increasing the hydrogen supplement rate, especially at the combustion middle period, but they are slowly increased by increasing the initial pressure. Also, the maximum ion and luminescent signals of flame are acquired at central positon of combustion chamber, and their appearing times are shorten by lowering the initial pressure and increasing the hydrogen supplement rate.

合金工具鋼의 와이어 컷 放電 加工面에 대한 트라이볼로지적 特性

변운봉,김석삼 경북대학교 산업기술연구소 1994 産業技術硏究誌 Vol.22 No.-

In this paper was examined the tribological characteristics of the worn surface of alloy tool steel STD11, machined by Wire-cut to choose the best work condition. In heat treating the specimens, after quenching in a vacuum furnace, each specimens were treated low tempering and high tempering. Then the 1st cut and 2nd cut were made with different conditions. After that the friction and wear test, for the microscophic observation of worn surface, by using SEM carried out to investigate wear process. The result obtained through this study are summarized as follows. The friction coefficient of the 2nd cut surface was greater than that of the 1st cut surface obtained by Wire-cut E D M. The wear rate of cut surface was higher than that of 1st cut surface obtained by Wire-cut E D M. The wear rate of the Wire-cut E D M surface after high tempering was lower than that surface after low tempering. The Wire-cut E D M surface has a wear mechanism that induces brittle fracture when a crack is generated and grown up to a critical length due to stress concentrations around craters.

PTC 세라믹히터에 의한 가솔린기관의 시동성 개선연구(I)

柳正人,金俸錫 忠南大學校 産業技術硏究所 1996 산업기술연구논문집 Vol.11 No.1

In a carburating system, the fuel keeps vaporizing after injected at the carburetor as droplets. But in cold weather, large amount of fuel remain as liquid phase, causing the increase of fuel consumption rates and harmful exhaust gas emissions. These problems can be solved by using the Positive Temperature Coefficient ceramic heaters. In the application experimental part, the Early Fuel Evaporation honeycomb heater was selected to test the performance of gasoline engine. The main results obtained from the performance test of gasoline engine can be summarized as follows. The drivability and idling stability became better and the fuel economy was improved by 17.7%. The HC and CO exhaust gas were cut down by 45% and 20%, respectively. The warm-up characteristic was improved by 20%.

Supine Bicycle Ergometer 운동이 뇌파와 기분상태에 미치는 영향

윤진환,정일규,김영표,김종오,이희혁,오봉석,김창주 대한스포츠의학회 2003 대한스포츠의학회지 Vol.21 No.1

In this study we investigated the effects of supine ergometer exercise on physiological and psychological relaxation. Seven healthy young men(aged 24.4±2.00years) volunteered for the experiment. The experiment consisted of the following three successive segments" A pre-exercise period of 10 min, during which the subjects rested in a supine posture with their eyes closed for the final 5 min; an supine ergometer exercise period of approximately 10 min, during which the subjects performed intensity of 50%HRmax exercises; A post-exercise recovery of 5 min, and a recovery of 10 min, which was similar to the pre-exercise rest period. The electroencephalo-graphic(EEG) activity of the central cortex of the brain were measured pre-exercise, post-exercise 5 min, and recovery phase 10min. Fast Fourier Transformation of the EEG was used to obtain power spectrum areas in the delta(0.5~4 Hz), theta(4~8 Hz), alpha(8~13 Hz) and beta(13~30 Hz) frequencies. We compared the relative power values(power %) of the electroencephalogram alpha bands(8~13 Hz) and korean edition of the profile of mood states(K-POMS) before and after the supine ergometer exercise. We also estimated the percentage of maximal heart rate(%HRmax) throughout the experiment to ascertain the intensity of the supine bicycle ergometer exercise. The results of %HRmax indicated that the intensity of supine exercises practised in the experiments ranged from low to moderate. The power % of EEG alpha bands had increased significantly after the supine ergometer exercise compared with the pre-exercise rest(p<0.05). From the POMS results, we observed that positive mood(vigour) increased and negative mood(tension, depression, and total mood)decreased significantly after the supine ergometer exercise(p<0.05). This study found that the subjects showed increased physiological and psychological indices of relaxation after supine bicycle ergometer exercise.

운동형태의 차이가 Alloxan유발 당뇨쥐의 혈당 및 인슐린 농도에 미치는 영향

윤진환,정일규,김종오,이희혁,지용석,오봉석,채정룡 대한스포츠의학회 2003 대한스포츠의학회지 Vol.21 No.1

The Purpose of this study was to investigate the effect of exercise intensity on blood glucose and insulin levels in diabetic rats with alloxan. Twenty sprague-dawley male rats were assigned to power training groups(n=10) and endurance training groups(n=10). Diabetes was induced by single injection of alloxan(50 mg/kg B.W) Blood glucose and insulin were determined every week for 4-weeks. The conclusion of this study follows as below: 1) There was significantly different on blood glucose levels in two groups. 2) There was significantly different on insulin levels in two groups These results suggest that proper exercise intensity in diabetic rats can significantly decrease blood glucose and insulin level and make good glycemic control. In conclusion, it has been found that regular prolonged endurance training with diabetic rats, improves insulin and blood glucose.

정신과 외래환자의 약물치료 반응과 심박동 변이의 변화 양상

이상규,이홍석,김인주,김형태,김도훈,손봉기 大韓神經精神醫學會 2006 신경정신의학 Vol.45 No.6

Objectives : The purpose of this study was to investigate the change of heart rate variability after antidepressant treatment in depressed or anxious patients. We tried to find the usefulness of heart rate variability as a predictive marker of response to pharmacological treatments in the psychiatric field. Methods : Forty-seven patients with major depression, anxiety disorder, and somatoform disorder were treated over 4 weeks with antidepressants and were then classified as responders or nonresponders according to Hamilton depression scales or CGI scores. The HRV variables were measured and compared among the responders/nonresponders and the matched normal control. Results : The responders group exhibited low heart rate, low PSI, high SDNN, RMSSD, HRV index, NN50, pNN50, LNTP, LNLF, and LNHF compared with the nonresponders after 4 weeks antidepressant treatment. However, no significant differencein HRV vanables was observed between the responders group after treatment and the nonnal control group and the responsegroup after treatment. Conclusion : These results indicate that HRV variables would are normalized after successful antidepressant treatment and it that HRV has some possible uses as a predicting marker of antidepressant response.

Influence of Surface Property on the Crystallization of Hentetracontane under Nanoscopic Cylindrical Confinement

Kim, Bong Seock,Jeong, Young Gyu,Shin, Kyusoon American Chemical Society 2013 The journal of physical chemistry. B, Condensed ma Vol.117 No.19

<P>The crystallization behavior and the orientation of linear alkane hentetracontane (C41) confined in cylindrical nanoporous alumina templates with different surface energies were investigated by nonisothermal crystallization and X-ray diffraction. The surface of pristine nanoporous alumina was modified to have low surface energy by grafting with polydimethylsiloxane. In the pristine nanoporous alumina, C41 crystallized at two crystallization temperature ranges, lower than bulk, and exhibited the decreased Avrami exponents. C41 in the surface-modified nanoporous alumina showed the inhibition of crystallization at higher temperature range among the two crystallization temperature ranges but the enhancement of crystallization at much lower temperature ranges than in the pristine nanoporous alumina. It was clearly shown that those variations of crystallization behavior imply the surface effect on crystallization. The crystal orientation was also affected by surface–modification of the alumina template. The <I>a</I>-axis of orthorhombic C41 crystals in the pristine nanoporous alumina was preferentially oriented parallel to the pore axis, while <I>b</I>- and <I>c</I>-axes were perpendicular to the pore axis. C41 crystals in the surface-modified nanoporous alumina showed two types of orientation. One was identical to that in the pristine nanoporous alumina, and the other was the orientation that the crystals were tilted with respect to the <I>c</I>-axis as the (110) plane parallel to the pore axis.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/jpcbfk/2013/jpcbfk.2013.117.issue-19/jp308678b/production/images/medium/jp-2012-08678b_0011.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/jp308678b'>ACS Electronic Supporting Info</A></P>

Analysis of Diesel Combustion Flames with Highly Oxygenated Fuels

Kim Bong-Seock,Ogawa Hideyuki The Korean Society of Marine Engineering 2005 한국마린엔지니어링학회지 Vol.29 No.6

With highly oxygenated fuels the smoke emissions decreased sharply and linearly with increases in the fuel oxygen content and entirely disappeared at an oxygen content of $38wt-\%$ even at stoichiometric mixture conditions The NOx also decreased monotonically with increases in oxygen content. and thermal efficiency slightly improved because of a reduction in cooling loss and improvement in the degree of constant volume combustion. The mechanisms of the significant reductions in emissions and improvement in engine performance were analyzed with a bottom view type DI diesel engine. Together with direct flame images, flame images were taken through an optical fetter passing only two wavelengths for use in 2-D two-color analysis. The results showed that luminous flame decreased significantly with increases in oxygen content and was not detected for neat dimethoxy methane(DMM). The decrease in flame luminosity with highly oxygenated fuels corresponds with decreases in soot and cooling losses, including those due to heat radiation. The 2-D two-color flame analysis indicated that the high temperature flame and high KL factor areas apparently decreased with increasing fuel oxygen content. These results correspond strongly with decreases in NOx. smoke. and cooling loss with increases in oxygen content.