• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.48 no.5
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• pp.355-361
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• 2020

Among these satellites, low - orbit small satellites with military characteristics require multi - target observation, and demand for high-resolution photographs and images is increasing. Fast maneuverability is the most important factor for high-resolution images and multi - target observations. However, in the case of a small satellites, it is possible to perform the attitude maneuver if it has high speed, but the residual vibration occurs when the attitude maneuver is completed and the next attitude maneuver is completed. In this study, to verify the vibration characteristics of the plate generated after attitude maneuver, an experimental fixture for simulating the attitude maneuver was fabricated and tested. In addition, Eddy Current Damper (ECD) using Eddy Current Brake system (ECB) is proposed as a passive damping method using permanent magnet to reduce vibration. A mathematical model was established to apply ECD and it was experimentally implemented according to the magnetic flux density and the air gap of the permanent magnet. One plate of four solar panels (plate) was specified, the residual vibration reduction performance after the test was verified experimentally.

• The Korean Journal of Food And Nutrition
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• v.22 no.2
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• pp.272-278
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• 2009

This study was carried out to evaluate the physicochemical characteristics of fermented milks containing mulberry leaf extract. The mulberry leaf extracts were added to fermented milk at $0{\sim}2.0%$. The pH, acidity, numbers of viable cells, chemical composition and color values of fermented milk preparation were analyzed, and these samples were subjected to a taste test panel. As the ratio of mulberry leaf extract increased, the pH value of the fermented milk decreased proportionally and acidities increased significantly. The numbers of viable cells was highest in the fermented milk sample containing 0.5% mulberry leaf extract. In the chemical composition analyses, increases in the concentration of mulberry leaf extract led to a significant increase in crude protein, crude fat, and crude ash contents and a significant decrease in lactose content. Ca, Mg and K in the fermented milk were also significantly increased with the addition of mulberry leaf extract. As mulberry leaf extract amount increased, the lightness and redness values decreased, while the yellowness value increased. From the sensory evaluation of the fermented milk containing mulberry leaf extract, color, taste, texture and overall acceptability of the fermented milk sample containing 1% mulberry leaf extract was found to be much better than those of the other groups.

• Korean journal of food and cookery science
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• v.18 no.6
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• pp.670-676
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• 2002

Four different brands of commercial and a home-made jujube tea were analyzed for physicochemical properties (sugar content, acidity, color, viscosity, transparency, texture) and sensory characteristics by using 7-point scoring test from 18 experienced panel members. Also, the opinion of food and nutrition specialists on the commercial jujube teas were assessed using a questionnaire, which were hand-delivered to 530 subjects consisting of university students and faculties of Department of Food and Nutrition at 8 cities(Seoul, Incheon, Youngin. Taejon, Chungju, Taegu, Kwangiu, Pusan) in Korea and the complete data of 328 subjects were statistically analyzed using SPSS Program for Window. The questionnaire consisted of socio-demographics, frequency and occasion of purchasing, opinion of quality and improvement points, and sensory characteristics. Commercial jujube teas (3 different brand) were lower in sugar content, pH, transparency, color (Hunter L, a and b value), and viscosity than the home-made one, whereas only one brand was higher in viscosity and lower in transparency than home-made one. Also, overall preference for commercial jujube teas was significantly love. than that for home-made one (p＜0.05). Especially, the scores of overall preference for 3 commercial jujube teas (2.1-3.3) were much lower than that of home-made one (6.1). Points to be improved for commercial jujube teas were indicated as the amount of jujube (30.0%), taste (23.8%), sweetness (22.0%), and flavor (14.4%) in order. Sensory attributes showing positive correlations with overall preference of jujube tea were the taste(0.566), amount of jujube(0.449), and flavor(0.335).

• Journal of Korean Society of Steel Construction
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• v.19 no.6
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• pp.751-760
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• 2007

The purpose of this study is to evaluate the seismic performance of the frame which is assumed to be used with Welded Unreinforced Flange-Bolted web (WUF-B) connections and detailed in compliance with FEMA 350 recommended seismic design criteria. In FEMA 350, these types of connections are only valid for Ordinary Moment-Resisting Steel Frames (OMRSFs). For this purpose, based on test results, we proposed an analytical model for the Post-Northridge WUF-B connections with different panel zone strength ratios. Using the connection model, SAC Phase II three and nine-story frames were modeled and analyzed. From a nonlinear static pushover analysis, ductility, maximum strength, and the maximum interstory drift ratio were investigated for buildings with Post-Northridge details. Moreover, the maximum interstory drift ratio of each performance level (IO and CP) was also investigated through Incremental Dynamic Analysis (IDA). Analytical results were compared with those of buildings with either Pre-Northridge connection or ductile connections with no fracture. The analytical results showed that buildings with Post-Northridge WUF-B connections provide superior strength and interstory drift ratio capacity than buildings with Pre-Northridge WUF-B connections.

• Journal of the Korean Society of Food Science and Nutrition
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• v.22 no.4
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• pp.428-432
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• 1993

For the elucidation of some informations on juice manufacturing properties of tomato, physical, chemical and sensory characteristic were analyzed for two groups of cultivation pattern-nonproped cultivation (5 varieties) and proped cultivation (4 varieties). The proped cultivation showed higher sugar content of juice than the nonproped on. Among the proped Jeokpung and Master 2 showed high value of sugar content. The lowest value of sugar content was observed in 79078$\times$ARC of the nonproped. There was no difference in acidity between cultivation groups but high value was observed in TM103, Jinhong from the nonproped and Jeokpung from the proped. There was no difference in pH between tomoto juice. High content of vitamin C was observed in 79078$\times$CL1561 from the nonproped and 76Moll-3-2-2 from the proped. High viscosity was observed in 79078$\times$CL1561 from the nonproped and Horgju from the proped. The nonproped showed greater value in dominant wavelength than the proped. Good Hope showed the greatest value in dominant wavelength, color score of panel test and yield. It was found that Good Hope from the nonproped and Jeokpung from the proped were suitable for juice processing. But better quality of juice can be possibly made by using various varieties rather than using single variety because each variety has each goodness of juice preparation separately.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.27 no.3
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• pp.240-246
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• 1994

This study was designed to determine the optimum pigment concentration supplemented in diet and feeding periods on the pigmentation of rainbow trout(Oncorhynchus mykiss) by using acetone-extracts of ascidian tunic as a natural pigment source. The eight pigmented diets contained carotenoid of ascidian tunic extracts at concentrations of 0, 200, 400, 800, 1,600 and 3,200mg/kg of diet, carophyll pink at concentration of 800mg/kg and commercial diet. No difference in pigment concentration was found between the ascidian extracts group and the control group until 4 weeks, but the redness of muscle and integument in the 1,600, 3,200mg/kg diet and carophyll pink was increased in the dorsal and caudal areas of fish from 6 weeks of age. In the sensory panel test, fish fed the ascidian tunic extracts diet were similar to those fed the carophyll pink diet. The optimum concentration and feeding periods for pigmentation of rainbow trout was found to be ascidian tunic extracts of 1,600mg/kg diet for 8 weeks.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.36 no.11
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• pp.1345-1352
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• 2012

This paper aims to evaluate the low-velocity impact responses and mechanical properties of balsa-wood and urethane-foam core materials and their sandwich panels, which are applied as the impact limiter of a nuclear spent fuel shipping cask. For the urethane-foam core, which is isotropic, tensile, compressive, and shear mechanical tests were conducted. For the balsa-wood core, which is orthotropic and shows different material properties in different orthogonal directions, nine mechanical properties were determined. The impact test specimens for the core material and their sandwich panel were subjected to low-velocity impact loads using an instrumented testing machine at impact energy levels of 1, 3, and 5 J. The experimental results showed that both the urethane-foam and the balsa-wood core except in the growth direction (z-direction) had a similar impact response for the energy absorbing capacity, contact force, and indentation. Furthermore, it was found that the urethane-foam core was suitable as an impact limiter material owing to its resistance to fire and low cost, and the balsa-wood core could also be strongly considered as an impact limiter material for a lightweight nuclear spent fuel shipping cask.

• Journal of Animal Science and Technology
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• v.55 no.5
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• pp.461-466
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• 2013

This study compared the quality characteristics between meat ball products in domestic market. Five types of meat ball products(T1, T2, T3, T4 and T5) were purchased in domestic market. In terms of the chemical composition, meat ball products ranged 53.92~63.45% in moisture contents. In terms of quality characteristics, T2 showed a significantly higher pH value and cooking loss than the others (p<0.05). In terms of deformation rate, T2 showed a significantly higher contraction of height than the others (p<0.05). In the panel test, T1 showed a significantly higher score in saltiness, flavor, color, appearance and total acceptability (p<0.05). Overall, meat ball products showed considerable differences in chemical composition, cooking loss, Hunter color values, and texture profile due to differences in raw materials, recipes, and weights.

• Current Research on Agriculture and Life Sciences
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• v.6
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• pp.121-127
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• 1988

Ramyon(deep fat fried instant noodle with palm oil) preserved in sunlight, room temp. ($20{\pm}5^{\circ}C$), incubator ($30{\pm}2^{\circ}C$) and corrugated fiber board box to investigate the oxidative changes of the Ramyon lipids. In the study, changes in acid value, peroxide value, carbonyl value, TBA value, fatty acid composition, iodine value and panel test were determined with the lipids extracted from the Ramyon samples in intervals for a period of 20 weeks. Acid value, peroxide value, carbonyl value and TBA value of the Ramyon lipid were increased slightly during the storage in aluminum foil package in the corrugated fiber board box in the dark room. They did not appear the oxidative rancid odor at the end of 20 weeks storage. Acid value, peroxide value, carbonyl value and TBA value of the samples under room temp., incubator slightly during storage, while a sharp increase of those values were noticed with the samples of sunlight. Especially, the TBA value of the Ramyon lipid under sunlight markedly increased within 14 weeks and then decreased. Oxidative rancid odor appeared at the end of 10 weeks storage under sunlight, while it took 18 weeks with the sample stored under room temp. and incubator. During the storage under incubator and sunlight for 18 weeks, the content of oleic, linoleic acid decreased, while palmitic and stearic acid increased. However, only small changes were noticed in iodine value of the samples.

• Journal of Korea Technology Innovation Society
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• v.20 no.3
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• pp.546-575
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• 2017

This paper investigates the effects of public R&D support on medium-sized firms' R&D investment. The paper collects a panel dataset of Korean manufacturing firms' R&D investment and public support, and employs the DID (difference-in-differences) regression for the test of stimulating or crowding-out effect. Empirical analysis examines how the effect of public R&D support differs between small and medium-sized firms and whether firm size and technological capability moderate the effect in the sample of medium-sized firms. Empirical results show that public R&D support tends to generally stimulate private pure R&D investment for both small and medium-sized firms. Comparing the results for small and medium-sized firms, this paper finds that the stimulating effect is relatively larger and more significant for medium-sized firms, while the effect is not significant for small ones. Furthermore, the paper shows that the stimulating effect of public R&D subsidy on private R&D investment is relatively stronger for medium-sized firms with superior technological competence and the effect of tax support is greater for incompetent firms. These results suggest that public R&D policies and R&D programs, differentiated from those for existing small firms, are necessary for medium-sized firms to stimulate private R&D continuously and formulated carefully by considering firm size, technological capability and growth potential.