Lateral Sloshing Analysis by CFD and Experiment for a Spherical Tank

김귀진,이희남,전완호,정주원,황도순 한국항공우주학회 2020 International Journal of Aeronautical and Space Sc Vol.21 No.3

Propellant sloshing is one of the potential sources of disturbance which affects the stability and structural integrity of space vehicles. In this study, using a small scale model of the first Korean lunar orbiter fuel tank, which is partially filled with liquid fuel, the dynamic lateral sloshing has been simulated by CFD analysis for various fill-levels. Spherical tank geometry was assumed, because it is one of the options for the fuel tank. After applying an accelerated motion to the fuel tank, the dynamic sloshing forces exerted on the tank wall in lateral directions during a free sloshing motion were measured and analyzed to identify the sloshing frequencies. The results show very good consistency with the mathematical and experimental studies from available sources in NASA technical reports. A simple inexpensive experimental work was also performed successfully to verify the fundamental slosh frequency. The methodology developed here would be useful for understanding the slosh dynamics and for modeling of the propellant sloshing in a fuel tank of an arbitrary geometry.

Effect of Fucoidan on Expression of Diabetes Mellitus Related Genes in Mouse Adipocytes

김귀진,이옥환,Han-Chul Lee,Young-Cheul Kim,이부용 한국식품과학회 2007 Food Science and Biotechnology Vol.16 No.2

Fucoidan (fucan sulfate) is a fucose-containing sulfa~ed pol~saccharide frO!? br~W11 algae such as FlfcUS vesiculosus, Ecklonia kurome, and Cladosiphon okamuranus. The aim of this study. was to investigate the effect of fuC?ldan on the expression of diabetes-related genes in mouse cell line 3T3-Ll. 3T3~L~ adipocytes were ~ultured. for 48 hr WIth or without fucoidan (10, 100, and 500 ppm) on a 60 mm dish. Reverse transcription polymerase chamre~ctl?n (RT-P~R) was used for measurement of peroxisome proliferators activated receptor y (PPARy), CCAAT/enhancer bmdmg protem a (CI EBPa), and glucose transporter 4 (GLUT4) RT-PCR analysis reve~led that expression level of GLU~4, PPARy, and C/EBPa mRNAs increased with fucoidan treatment from 10 to 500 ppm m a dose-dependent manner, Fucoidan appears to enhance insulin sensitivity by increasing the expression level of diabetes-re~at~d genes in.3T3-Ll a~ipocytes. Therefore, fucoidan is potentially useful as a natural therapeutic material for hyperglycemia in type II diabetes patients

농촌 중년여성의 건강행위와 관련요인

김귀진(Kwi-Jin Kim),박재용(Jae-Yong Park),한창현(Chang-Hyun Han) 한국농촌의학 지역보건학회 2001 농촌의학·지역보건 Vol.26 No.1

Korean ginseng extract ameliorates abnormal immune response through the regulation of inflammatory constituents in Sprague Dawley rat subjected to environmental heat stress

송지현,김귀진,최서윤,고은정,박종대,이부용 고려인삼학회 2019 Journal of Ginseng Research Vol.43 No.2

Background: Increases in the average global temperature cause heat stresseinduced disorders by disrupting homeostasis. Excessive heat stress triggers an imbalance in the immune system; thus protection against heat stress is important to maintain immune homeostasis. Korean ginseng (Panax ginseng Meyer) has been used as a herbal medicine and displays beneficial biological properties. Methods: We investigated the protective effects of Korean ginseng extracts (KGEs) against heat stress in a rat model. Following acclimatization for 1 week, rats were housed at room temperature for 2 weeks and then exposed to heat stress (40C/2 h/day) for 4 weeks. Rats were treated with three KGEs from the beginning of the second week to the end of the experiment. Results: Heat stress dramatically increased secretion of inflammatory factors, and this was significantly reduced in the KGE-treated groups. Levels of inflammatory factors such as heat shock protein 70, interleukin 6, inducible nitric oxide synthase, and tumor necrosis factor-alpha were increased in the spleen and muscle upon heat stress. KGEs inhibited these increases by down-regulating heat shock protein 70 and the associated nuclear factor-kB and mitogen-activated protein kinase signaling pathways. Consequently, KGEs suppressed activation of T-cells and B-cells. Conclusion: KGEs suppress the immune response upon heat stress and decrease the production of inflammatory cytokines in muscle and spleen. We suggest that KGEs protect against heat stress by inhibiting inflammation and maintaining immune homeostasis.

Korean Red Ginseng and Korean black ginseng extracts, JP5 and BG1, prevent hepatic oxidative stress and infl ammation induced by environmental heat stress

송지현,김귀진,Sungwoo Chei,Young-Jin Seo,Kippeum Lee,Boo Yong Lee 고려인삼학회 2020 Journal of Ginseng Research Vol.44 No.2

Background: Continuous exposure to high temperatures can lead to heat stress. This stress responsealters the expression of multiple genes and can contribute to the onset of various diseases. In particular,heat stress induces oxidative stress by increasing the production of reactive oxygen species. The liver isan essential organ that plays a variety of roles, such as detoxification and protein synthesis. Therefore, itis important to protect the liver from oxidative stress caused by heat stress. Korean ginseng has a varietyof beneficial biological properties, and our previous studies showed that it provides an effective defenseagainst heat stress. Methods: We investigated the ability of Korean Red Ginseng and Korean black ginseng extracts (JP5 andBG1) to protect against heat stress using a rat model. We then confirmed the active ingredients andmechanism of action using a cell-based model. Results: Heat stress significantly increased gene and protein expression of oxidative stresserelatedfactors such as catalase and SOD2, but treatment with JP5 (Korean Red Ginseng extract) and BG1(Korean black ginseng extract) abolished this response in both liver tissue and HepG2 cells. In addition,JP5 and BG1 inhibited the expression of inflammatory proteins such as p-NF-kB and tumor necrosisfactor alpha-a. In particular, JP5 and BG1 decreased the expression of components of the NLRP3inflammasome, a key inflammatory signaling factor. Thus, JP5 and BG1 inhibited both oxidative stressand inflammation. Conclusions: JP5 and BG1 protect against oxidative stress and inflammation induced by heat stress andhelp maintain liver function by preventing liver damage.

주진천 수변개발 기본계획

유성필,김귀진,한규환,황지욱 전북대학교 부설 휴양및경관계획연구소 2010 휴양및경관연구 (J East Asian Landscape Studies) Vol.4 No.1

본 계획은 전라북도 고창군 아산면에 위치한 주진천을 대상으로 수변공간의 자연하천으로 재정비하는데 초점을 맞추고 있다. 주진천은 주변지역의 개발에 따른 수질오염과 수변공간의 방치가 심화되고 있었다. 따라서 주진천의 생태적 기능을회복하고 수변지역을 관광자원으로 개발하기 위하여 체계적 정비와 개발에 이바지할 수 있는 주진천 정비와 수변개발계획의기본 방향을 제시하고자 한다. 핵심적 계획요소는 세가지의 주제로 분류되는데 첫째는 주 오염원류에 해당하는 상류유역의수질개선, 둘째는 생태하천 기능의 회복을 위한 생태적 수질개선 방안, 셋째는 수변공간의 방문객 친화적 이용을 도모하기위한 개발방안을 제시하는 것이다. This masterplan is for a design of a waterfront on Jujin Creek in Gochang City. The proposal of this plan sets several main criteria according to the local characteristics as follows: 1. the water quality has to be improved from the upper area, as it is the origin of water pollution, 2. for the improvement of water quality the use of ecologically sound methods is are strongly proposed, and 3. the waterfront area has to be developed as resident-friendly. In conclusion, this waterfront is composed of 3 theme areas: an ecological waterflow area, an entertainment & rest area, and an observation area. Accordingly, it is to be developed as a mixed-use space for enjoying, resting, learning and playing for all visitors and residents.

연구논문 : 농촌도시 김제의 인구변화 특성에 관한 연구

황지욱 ( Jee Wook Hwang ),김귀진 ( Kwi Jin Kim ) 전남대학교 지역개발연구소 2013 지역개발연구 Vol.45 No.2

1960년대 이래 우리나라는 40여년 간에 걸쳐 급속한 경제성장과 발맞추어 급격한 도시화현상이 진행되어 왔다. 이러한 시기와 병행하여 이루어진 정책은 신도시와 신시가지를 개발하는데 초점을 맞춘 것이었는데, 이는 토지수요가 급증하며 가구의 핵가족화에 따른 결과와 맞물려 있었다. 따라서 도시지역은 지속적인 외연의 확장과 확산을 겪게 된다. 그러나 1990년대 말엽과 2000년대에 들어서 인구규모와 관련한 도시화율은 점차 둔화된 형태를 타나내기 시작하였으며, 성숙기에 접어들게 되었다. 본 연구에서는 이러한 현상의 과정에서 농촌형 구조를 띠고 있는 지방중소도시가 겪는 변화상을 살펴 보는데 초점을 맞추고 있다. 이러한 변화상을 인구이동과 변화의 관점에서 살펴보기 위하여 중다선형회귀분석을 활용하였으며, 1999년부터 2008년 사이의 데이터를 근거로 변수간의 상관관계를 파악하게 되었다. 그리고 이러한 결과값을 근거로 농촌형 지방중소도시의 인구변화와 이동에 대한 시사점을 파악해 보고자 하였다. 여기서 종속변수는 인구수에 해당하며 독립변수로는 학교 수, 병원 수, 1,000인당 의료 인력 수, 농자율, 도시화지역의 비율 및 전체 산업구조에 있어서 종사자 비율을 살펴 보았다. 이러한 분석의 결과, 초등학교의 수와 도시화 지역의 면적비율은 인구변화에 영향을 끼치는 가장 핵심적인 요인임을 확인할 수 있었다. 특히 학교의 경우 초등학교의 수가 인구의 변화와 이동에 가장 큰 영향을 끼치는 변수임을 확인할 수 있었다. Since 1960, Korea has been rapidly developed in line with the economic development for more than 40 years as well as the drastic urbanization process. In the mean time. involved policies were focused on new town and new street development to meet the increasing demand for lands and to increase the home distribution rate. Accordingly. cities achieved consistent and superficial expansion. In late 1990`s and 2000`s, however. the growth ratio of cities in terms of population has been dull and turned to the period of maturity. For this study. Multiple Linear Regression, an analysis method, is in usc and various parameters of Gimje city from 1999 to 2008 are collected. Here the dependant variable is the number of population and the finally selected independent variables arc number of schools, hospitals and health workforce per 1,000 population and ratio of agricultural land. urbanized land and workers in the entire industry. The result is as follows: the number of elementary schools and the ratio of urbanized land arc the main factors affecting the population alteration. In case of schools. the elementary schools shows the highest significance.

A New Approach to the Analysis of Tannin Concentration Using a Microelectronic Biosensor

노대현,이옥환,조주현,홍희도,김귀진 한국식품과학회 2013 Food Science and Biotechnology Vol.22 No.1

Wine tannins are essential to the astringency and color stabilization of red wine through the formation of tannin conjugates. It is important to determine the concentration of tannins during wine aging and fermentation. The aim of this study was to establish a new method that allows for real-time analysis of tannin content in wine and eliminates inconvenient processes, such as calibrations and/or enzyme reactions. The Folin-Ciocalteau spectrophotometry (FCS) was used a positive control and compared it with new microelectrode biosensor cyclic voltammetry (MBCV)method. The new approach was established that not only allows for real-time tannin detection but is also economical and does not require the use of a specific enzyme. The results are reproducible and provide a precise measurement of tannin content.