• Journal of The Korean Astronomical Society
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• v.37 no.5
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• pp.605-609
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• 2004

We present a set of high-resolution 3D MHD simulations exploring the evolution of light, supersonic jets in cluster environments. We model sets of high- and low-Mach jets entering both uniform surroundings and King-type atmospheres and propagating distances more than 100 times the initial jet radius. Through complimentary analyses of synthetic observations and energy flow, we explore the detailed interactions between these jets and their environments. We find that jet cocoon morphology is strongly influenced by the structure of the ambient medium. Jets moving into uniform atmospheres have more pronounced backflow than their non-uniform counterparts, and this difference is clearly reflected by morphological differences in the synthetic observations. Additionally, synthetic observations illustrate differences in the appearances of terminal hotspots and the x-ray and radio correlations between the high- and low-Mach runs. Exploration of energy flow in these systems illustrates the general conversion of kinetic to thermal and magnetic energy in all of our simulations. Specifically, we examine conversion of energy type and the spatial transport of energy to the ambient medium. Determination of the evolution of the energy distribution in these objects will enhance our understanding of the role of AGN feedback in cluster environments.

• Journal of the KSME
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• v.32 no.6
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• pp.496-503
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• 1992

상사실험법(analogous experimental method)이라 함은 물리적현상을 다른 물리적현상으로 변환 하여, 후자를 실험적으로 측정하여 전자의 제반 물리량을 얻는 과정을 말한다. 이 때 두 물리량 사이에는 수학적 상사관계, 특히 미분방정식 상의 유사관계가 성립함을 전제로 한다. 일반적으로 임의형상의 내부응력을 실험적으로 해석하는 데는 탄소성 변위를 직접 전기적저항으로 바꾸어 측정하는 방법(strain gauge method)이나 광파의 간섭무늬(fringe)로 가시화하는 광탄성 법(photoelastic method), 또는 전자계산기를 이용하여 분할요소해석의 연계집적으로서 얻는 유 한요소법(F.E.M) 등이 널리 사용되고 있으나, 이들은 다같이 그 나름대로의 장단점을 지니고 있다. 전기저항식은 변형을 직접 측정할 수 있어 측정의 오차를 줄일 수 있고, 특히 실물측정과 동하중 해석에는 큰 강점이 있으나, 점해석(point by analysis)이기 때문에 전시야적인 분포를 파악하기 어렵다. 또한 광탄성법은 명료한 전시야적 분포를 얻을 수 있지만 모형해석(model analysis)이기 때문에 정밀한 모형제작의 어려움이 수반되며, F.E.M.(B.E.M.도 포함)은 복잡한 형상에서의 요소분할이 매우 어렵고, 경계조건의 정확한 설정에 문제가 있다. 따라서 여러 실험적 방법은 실측대상에 따라 그 장단점을 감안하여 선택되어야 하며, 이 글에서 논술하고자 하는 상사실험법에 의한 응력해석도 이러한 관점에서 지금까지의 일련의 연구결과를 종합하여 그 효 용적인 용도, 응용 및 그 전망과 더불어 장차 해결하여야 할 2,3의 문제를 제시하고자 한다.

• Macromolecular Research
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• v.17 no.5
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• pp.289-295
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• 2009

Low viscosity aromatic hyperbranched polyester epoxy resin (HTBE) was synthesized by the reaction between epichlorohydrin (ECH) and carboxyl-end hyperbranched polyester (HTB) which was prepared from inexpensive materials $A_2$ (1,4-butanediol glycol, BEG) and $B_3$ (trimellitic anhydride, TMA) by pseudo one-step method. The molar mass of the HTB was calculated from its acid value by "Recursive Probability Approach". The degree of branching (DB) of the HTB was characterized by model compounds and $^1H$ NMR-minus spectrum technology, and the DB of the HTB was about $0.47{\sim}0.63$. The viscosity and epoxy equivalent weight of the HTBE were $3,600{\sim}5,000\;cp$ and lower than 540 g/mol respectively. The reaction mechanism and structure of the $AB_2$ monomer, HTB and HTBE were investigated by MS, $^1H$ NMR and FTIR spectra technology. The molecular size of HTBE is under 8.65 nm and its shape is ellipsoid-like as determined by molecular simulation.

• Food Science and Preservation
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• v.8 no.2
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• pp.146-150
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• 2001

The candy was prepared from starch syrup and sugar added with puree, extract and powder of Doraji, respectively. When three times extracted with 95% ethanol for 12 hours at $25^{\circ}C$ and 4 hours at 51$^{\circ}C$ and 78$^{\circ}C$, the extract contents were 22.6%, 25.8% and 25.3%, respectively. L-value of candy which was made of puree and extract of Doraji was lower than that of control. As the content of puree and extract of Doraji is increased, L-value was decreased. In case of added with puree, extract and powder, a and b-values were higher than those of control. Quality of the candy in sensory evaluation was the best when 20% of puree, 2% of extract and 5% of powder were added to the starch syrup and sugar, respectively. The result of preference test with various model, Bokjumony (Korea traditional purse) was the best in eye freel and ellipse was the best in mouth feel. The calories of candy were 2999.6 ㎉/100g in puree 20%, 358.3 ㎉/100g in extract 2% and 352.1 ㎉/100g in powder 5%.

• Journal of electromagnetic engineering and science
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• v.4 no.3
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• pp.128-136
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• 2004

In this paper,. with the aim of achieving the expected performance improvement for a polarization diversity system, we analyzed two-branch polarization diversity at the receiving end of a mobile link which a transmitter emits circularly polarized wave. In this analysis, to calculate the correlation coefficient considered by XPD(cross polarization discrimination) between the two received signals, a simple theoretical model of circular polarization diversity is adopted. From the analysis results, it is clearly seen that the correlation coefficient of circular polarization diversity evaluated by the XPD is less than that of conventional linear polarization diversity. And also, we designed and implemented a circular polarization diversity system with micro-strip antenna. By using the circular polarization diversity system, we analyzed the measured data in indoor NLOS(Non-Line-Of-Sight) environments. From this analysis results, it is also clearly seen that the diversity effect of circular polarization diversity system shows better performance compared to the conventional linear diversity system by about 3 dB high.

• Korean Journal of Health Education and Promotion
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• v.10 no.1
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• pp.9-20
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• 1993

This study was conducted to show one case model for a community nutrition program as a part of the public health systems. The purpose of this study is to evaluate the effect of the nutrition education through the Knowledge(K), Attitude(A), and Practice of the nutrition that is the Behavior-Diagnosis(Be-D). The Nutrition Education was done for 33 housewives whom live in Sudong-Myeun, Namyangju-Kun, Kyungki-Do. It had been performed eight times during April 3rd through May 30th, 1991. We investigated actual conditions of objects about K, A, Be-D in the nutrition, and the Food Environment(En) separately before and after the nutrition education by questionnaire and interview. The results of the research turned out as follows ; 1. The comparison of the scores before and after nutrition education showed significant increase in the knowledge and attitude. 2. The scores of the Be-D were also significantly higher after education, especially in the number of foods taken per day, the balanced diet, the general food habits for adult, and amounts of intake of nutrients showed significant increase of lipid, calcium, Vit. A, $Vit B_2$, Vit. C after nutrition education. 3. Multiple regression analysis showed that the scores of the Knowledge and En were significantly associated with the number of food taken per day for condition of adjusting socio-demografic factor and A effect. Also, En was important variable in explanation of the balanced diet and A, En were important in the general food habits for adult.

• Journal of computational fluids engineering
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• v.20 no.3
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• pp.20-26
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• 2015

This paper introduces a computational method for analysis of the 6-DOF motions of a ship in waves using an overset grid technique which consists of inner and outer domains for representing body motions and numerical wave tank, respectively. High order interpolation scheme is employed to increase numerical accuracy over the interface where physical values, such as velocities and pressure, interact between the inner and outer domains. The numerical schemes and algorithm are addressed in the present paper. An application to motion of KCS container carrier in head waves is presented, and the comparison of responses on heave and pitch motions shows good agreement with those of model tests.

• Journal of Biosystems Engineering
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• v.32 no.3
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• pp.160-165
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• 2007

This study was conducted to evaluate beef using a color machine vision system. The machine vision system has an advantage to measure larger area than a colorimeter and also could measure other quality factors like distribution of fats. However, the machine vision measurement is affected by system components. To measure the beef color with the machine vision system, the effect of color balancing control was tested and calibration model was developed. Neural network for color calibration which learned reference color patches showed a high correlation with colorimeter in L*a*b* coordinates and had an adaptability at various measurement environments. The trained network showed a very high correlation with the colorimeter when measuring beef color.

• International Journal of Automotive Technology
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• v.7 no.7
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• pp.785-793
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• 2006

The topic of this study is the control strategy of a mild hybrid electric vehicle (HEV) equipped with a continuously variable transmission (CVT). A brief powertrain and vehicle configuration is introduced followed by the control strategy of the HEV with emphasis on two key parts. One of them is an ideal operating surface (IOS) that operates the CVT powertrain optimally from the viewpoint of the tank-to-wheel efficiency. The other is a charge sustaining energy management to maintain the battery state of charge (SOC) within an appropriate level. The fuel economy simulation results of the HEV over standard driving cycles were compared with those of the baseline vehicle. Depending on the driving cycle, 1.3-20% fuel saving potential is predicted by the mild hybridisation using an integrated starter alternator (ISA). The detailed energy flow analysis shows that the majority of the improvement comes from the idle stop function and the benefits for electrical accessories. Additionally, the differences between the initial and the final SOC are in the range $-1.0{\sim}+3.8%$ in the examined cycle.

• Interdisciplinary Bio Central
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• v.3 no.1
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• pp.4.1-4.7
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• 2011

Forty-seven wild accessions of Lotus japonicus Regal (Japanese trefoil) indigenous to Japan were investigated for nine morphological characters. Average temperature and annual precipitation were negatively correlated with stem color and seed weight. On the other hand, latitude was positively correlated with these traits. Consequently, accessions from sites at higher latitudes with low temperatures and precipitation tend to have dark red stems and heavy seeds. Cluster analysis based on nine morphological characters classified 47 wild accessions into six major groups. Cluster I included four accessions of tall and erect plants. These plants are phenotypically similar to commercial variety 'Empire'. Cluster II consisted of three accessions of creep plants with pale red stems. Cluster III contained 24 accessions that had average values for all morphological characters evaluated. Cluster IV included two accessions of erect plants with rounded leaflets and dark red stems. Cluster V included four accessions of small, creep plants with pale red stems. Cluster VI included seven accessions of small and erect plants, a phenotype that also applies to ?Gifu B-129?, which is used as experimental strain worldwide. These data were deposited into LegumeBase, an online database (http://www.legumebase.brc.miyazaki-u.ac.jp/) supported by the National BioResource Project (NBRP) in Japan.