• Food Science and Preservation
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• v.13 no.5
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• pp.634-642
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• 2006

This study was performed to investigate the effects of lotus root ethanol extinct (LRE) on 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase activity in vitro, and lipid metabolism in the serum and liver of rate fed normal or high cholesterol diet in vivo. LRE (200 mg/kg/day and 400 mg/kg/day) was administered only to rats with fed high cholesterol diet for 6 week. We divided into 6 groups: normal diet group (NC), high cholesterol diet group (1% cholesterol and 0.25% sodium cholate)(HC), LRE 200 mg/kg treated group (NC-LREL), LRE 400 mg/kg teated group (NC-LREH), high cholesterol diet and LRE 200 mg/kg treated group (HC-LREL), and high cholesterol diet and LRE 400 mg/kg teated group (HC-LREH). LRE significantly inhibited the HMG-CoA reductase activity in a concentration-dependent manner in vitro. The body weight gain and liver weight of the high cholesterol diet group were higher than the normal diet group whereas the groups administered LRE were gradually decreased. The high cholesterol diet group increased serum triglyceride, total cholesterol, free cholesterol and LDL-cholesterol levels, and decreased atherogenic index, HDL-cholesterol and phospholipid levels as compared with the normal diet group. LRE administrated groups were increased in serum HDL-C/T-C, HDL-cholesterol and phospholipid levels, and decreased serum triglyceride, total cholesterol, free cholesterol, and LDL-cholesterol levels as compared with the high cholesterol diet group. These effect of LRE within the high cholesterol diet groups were concentration-dependent manners. There were no differences in the levels of serum triglyceride, total cholesterol, phopholipid, HDL-cholesterol and free cholesterol between normal diet groups. The hepatic LRE administrated groups than in the high cholesterol diet group. Teken together, it is suggested that LRE exerts hypocholesterolemic effect by reducing serum cholesterol concentration in rats with high cholesterol diet-induced hypercholesterolemia.

• Korean Journal of Food Science and Technology
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• v.42 no.6
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• pp.721-726
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• 2010

The objective of this study was to evaluate several varieties of aseptic-packaged cooked rice including Juanbyeo. Quality evaluations, such as by amylose, setback, toyo values and amylograms, were significantly higher in the Juanbyeo as compared to other samples. In addition, the Juanbyeo aseptic-packeged cooked rice showed significantly higher palatability characteristics and had a greater water absorption ratio than the other samples. For cold cooked rice, the relationship between palatability and texture was significantly high (p<0.01). Ilpumbyeo showed high scores for taste as a hot cooked rice, but as a cold cooked rice taste scores were lower than other samples. In the case of Juanbyeo cold cooked rice flavor was improved. When the Juanbyeo aseptic-packaged cooked rice was reheated in a microwave oven, it had better palatability than other varieties. Thus, the results of this study suggested that Juanbyeo can be effectively utilized as aseptic-packaged cooked rice.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.7
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• pp.853-859
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• 2006

This study was carried out to investigate the effect of egg shell calcium salt types and egg shell membrane on calcium metabolism in rats. Sprague-Dawley male rats, 4 weeks of age, were fed on free-calcium diets for 2 weeks after adjustment period. Rats weighing approximately $247{\pm}2.3g$ were divided into 6 groups and were fed on the experimental diets containing 0.2% calcium for 4 weeks. Experimental groups were as follows; {ES(M+)} (egg shell powder diet with egg shell membrane), {ES(M-)} (egg shell powder diet without egg shell membrane), {AC(M+)} (egg shell calcium acetate diet with egg shell membrance), {AC(M-)} (egg shell calcium acetate diet without eg shell membrane), {GC(M+)} (egg shell calcium glucuronate diet with egg shell membrane) and {GC(M-)} (egg shell calcium glucuronate diet without egg shell membrane). Bone length of femur was significantly different by the types (p<0.05) of egg shell calcium salts. Bone mineral density of femur showed the highest level in AC(M-) group. Calcium content of femur and calcium absorption rate were higher in egg shell calcium salt groups than in eg shell powder groups. Calcium absorption rate and retention were significantly different (p<0.05) among the types of eg shell calcium salts and were higher in the AC(M-) group than in the other groups. Alkaline phosphatase activity, parathyroid hormone and osteocalcin levels of serum showed no significant difference among the experimental groups. From the above results, it is concluded that bioavailability of calcium is higher in groups of egg shell calcium salts compared to those in egg shell powder, even though egg shell membrane has no effect on calcium metabolism. Thus, these findings suggest the possibility of using egg shell calcium salts as a functional food material related to calcium metabolism.

• Korean Journal of Breeding Science
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• v.42 no.6
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• pp.679-683
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• 2010

'Yeonjami' is a new sweetpotato variety developed for table use by Bioenergy Crop Research Center, National Institute of Crop Science (NICS), RDA in 2008. This variety was selected from the cross between 'Ayamurasakki' and 'Poly Cross' in 2000, and seedling and line selections were practiced from 2001 to 2003. Preliminary and advanced yield trials were carried out from 2004 to 2005. The regional yield trials were conducted at six locations from 2006 to 2008. 'Yeonjami' has cordate leaf, green vine and petiole, long elliptic storage root, purple skin and light purple flesh color of storage root. The average yield of storage root was 25.9 ton/ha in the regional yield trials, which was 15% higher than that of 'Sinjami' variety. Number of storage roots over 50 gram per plant was 2.9, and the average weight of one storage root was 153 gram. This variety was partly-resistant to Fusarium wilt and nematode. In addition, steamed 'Yeonjami' has higher polyphenol contents as 139.6 mg/100 g and higher biological activities as, which may improve the bioactivity in human.

• Korean Journal of Agricultural and Forest Meteorology
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• v.25 no.2
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• pp.61-70
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• 2023

In order to select high-quality winter cereal crops with high yield and to increase self-sufficiency rate of forage, their growth, yield, and feeding value of several cereal crops cultivated in winter were investigated in the paddy field of the southern region. Four wheat cultivars and green barley headed in early and mid-April, while oat and Italian ryegrass headed in early May. Fresh forage yields of wheats, green barley, and oat were significantly higher than that of Italian ryegrass, and dry forage yields of wheats and green barley were significantly higher than those of not only Italian ryegrass but also oat. In particular, the yield of a wheat cultivar 'Cheongwoo' was the highest. Mineral contents of wheat forages, even though low, were in the range 27.8~33.7mg·g^-1 DW suitable for feeding cattle and young female cows. Crude protein content of a wheat cultivar 'Cheongwoo' was high up to 7.6%, similarly to 7.0% requiring for feeding cattle. Feeding values such as total digestible nutrients (TDN) and relative feed value (RFV) of wheats and green barley were superior to those of oat and Italian ryegrass. In addition, dry matter rates of 4 wheat cultivars and green barley were in the range 30~40%, indicating that wheat cultivars and green barley could be used for various feeding purposes such as green or dried forage, and silage. Based on these results, wheat cultivars including 'Cheongwoo' and green barley could be encouraged to be cultivated in paddy fields, as high-quality winter forage crops with high yield.

• Journal of the Korean Society of International Agriculture
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• v.23 no.5
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• pp.537-545
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• 2011

This study was conducted to obtain basic information on physiological and proteomic responses of barley seedlings to salt stress. Shoot dry weight decreased significantly as the level of soil salinity increased. Salt stress-induced decrease of relative shoot dry weight was lower in cv. "Sanglok" than in cv. "Sunwoo". Under the salt stress, SPAD value decreased, and the value was higher in cv. "Sanglok" than in cv. "Sunwoo". Sodium ion content in the leaves increased as NaCl concentration increased, and the content was higher in cv. "Sunwoo" than in cv. "Sanglok". The K⁺/Na⁺ ratio was higher in cv. "Sanglok" than in cv. "Sunwoo". Salt stress-induced alterations in protein expression of the leaves were detected by two dimensional electrophoresis, and 47 protein spots showing altered expression were selected. Among the selected protein spots, 17 protein spots were up-regulated and 28 spots down-regulated in cv. "Sanglok". In cv. "Sunwoo", 14 protein spots were up-regulated and 27 spots down-regulated. Out of 47 deferentially expressed protein spots, 18 protein spots were identified using mass spectrometry and NCBI protein database. Among the identified proteins, ten proteins are known to be involved in various stress responses, but the others are not directly involved in stress responses.

• Journal of Intelligence and Information Systems
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• v.23 no.2
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• pp.19-38
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• 2017

Collaborative filtering (CF) algorithm has been popularly used for implementing recommender systems. Until now, there have been many prior studies to improve the accuracy of CF. Among them, some recent studies adopt 'hybrid recommendation approach', which enhances the performance of conventional CF by using additional information. In this research, we propose a new hybrid recommender system which fuses CF and the results from the social network analysis on trust and distrust relationship networks among users to enhance prediction accuracy. The proposed algorithm of our study is based on memory-based CF. But, when calculating the similarity between users in CF, our proposed algorithm considers not only the correlation of the users' numeric rating patterns, but also the users' in-degree centrality values derived from trust and distrust relationship networks. In specific, it is designed to amplify the similarity between a target user and his or her neighbor when the neighbor has higher in-degree centrality in the trust relationship network. Also, it attenuates the similarity between a target user and his or her neighbor when the neighbor has higher in-degree centrality in the distrust relationship network. Our proposed algorithm considers four (4) types of user relationships - direct trust, indirect trust, direct distrust, and indirect distrust - in total. And, it uses four adjusting coefficients, which adjusts the level of amplification / attenuation for in-degree centrality values derived from direct / indirect trust and distrust relationship networks. To determine optimal adjusting coefficients, genetic algorithms (GA) has been adopted. Under this background, we named our proposed algorithm as SNACF-GA (Social Network Analysis - based CF using GA). To validate the performance of the SNACF-GA, we used a real-world data set which is called 'Extended Epinions dataset' provided by 'trustlet.org'. It is the data set contains user responses (rating scores and reviews) after purchasing specific items (e.g. car, movie, music, book) as well as trust / distrust relationship information indicating whom to trust or distrust between users. The experimental system was basically developed using Microsoft Visual Basic for Applications (VBA), but we also used UCINET 6 for calculating the in-degree centrality of trust / distrust relationship networks. In addition, we used Palisade Software's Evolver, which is a commercial software implements genetic algorithm. To examine the effectiveness of our proposed system more precisely, we adopted two comparison models. The first comparison model is conventional CF. It only uses users' explicit numeric ratings when calculating the similarities between users. That is, it does not consider trust / distrust relationship between users at all. The second comparison model is SNACF (Social Network Analysis - based CF). SNACF differs from the proposed algorithm SNACF-GA in that it considers only direct trust / distrust relationships. It also does not use GA optimization. The performances of the proposed algorithm and comparison models were evaluated by using average MAE (mean absolute error). Experimental result showed that the optimal adjusting coefficients for direct trust, indirect trust, direct distrust, indirect distrust were 0, 1.4287, 1.5, 0.4615 each. This implies that distrust relationships between users are more important than trust ones in recommender systems. From the perspective of recommendation accuracy, SNACF-GA (Avg. MAE = 0.111943), the proposed algorithm which reflects both direct and indirect trust / distrust relationships information, was found to greatly outperform a conventional CF (Avg. MAE = 0.112638). Also, the algorithm showed better recommendation accuracy than the SNACF (Avg. MAE = 0.112209). To confirm whether these differences are statistically significant or not, we applied paired samples t-test. The results from the paired samples t-test presented that the difference between SNACF-GA and conventional CF was statistical significant at the 1% significance level, and the difference between SNACF-GA and SNACF was statistical significant at the 5%. Our study found that the trust/distrust relationship can be important information for improving performance of recommendation algorithms. Especially, distrust relationship information was found to have a greater impact on the performance improvement of CF. This implies that we need to have more attention on distrust (negative) relationships rather than trust (positive) ones when tracking and managing social relationships between users.

• The Journal of Small Business Innovation
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• v.19 no.2
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• pp.53-68
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• 2016

Motivation and activities for technological learning, entrepreneurship, innovation, and creativity are driving forces of economic development in Asian countries. In the early stages of technological development, technological learning and entrepreneurship are efficient ways in which to catch up with advanced countries because firms can accumulate skills and knowledge quickly at relatively low risk. In the later stages of technological development, however, innovation and creativity become more important. This study aims to identify a) the factors (learning capabilities) that influence technological learning performance and b) barriers to enhancing innovation capabilities for the creative economy and organizations. The major part of this study is related to learning capabilities in the post-catch-up era. Based on a literature review and observations from Korean experiences, this study proposes a technological learning model composed of various influencing factors on technological learning. Three hypotheses are derived, and data are collected from Korean machine tool manufacturers. Intense interviews with CEOs and R&D directors are conducted using structured questionnaires. Statistical analysis, such as correlation and ANOVA are then carried out. Furthermore, this study addresses how to enhance innovation capabilities to move forward. Innovation enablers and barriers are identified by case studies and policy analysis. The results of the empirical study identify several levels of firms' learning capabilities and activities such as a) stock of technology, b) potential of technical labor, c) explicit technological efforts, d) readiness to learn, e) top management support, f) a formal technological learning system, g) high learning motivation, h) appropriate technology choice, and i) specific goal setting. These learning capabilities determine firms' learning performance, especially in the early stages of development. Furthermore, it is found that the critical factors for successful technological learning vary along the stages of technology development. Throughout the statistical and policy analyses, this study confirms that technological learning can be understood as an intrinsic principle of the technology development process. Firms perform proactive and creative learning in the late stages, while reactive and imitative learning prevails in the early stages. In addition, this study identifies the driving forces or facilitating factors enhancing innovation performance in the post catch-up era. The results of the preliminary case studies and policy analysis show some facilitating factors such as a) the strategic intent of the CEO and corporate culture, b) leadership and change agents, c) design principles and routines, d) ecosystem and collaboration with partners, and e) intensive R&D investment.

• Korean Journal of Poultry Science
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• v.42 no.1
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• pp.33-40
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• 2015

This study was conducted to investigate the effects of dietary quercetin on growth performance, blood biochemical parameters, immunoglobulin, and blood antioxidant activity in broiler chickens. Three hundred twenty one-day old Ross broilers were divided 8 treatments (C(-), basal diet; C(+), basal diet with antibiotics; vitamin E 20 IU; vitamin E 200 IU; quercetin 20 ppm; quercetin 200 ppm; methoxylated quercetin 20 ppm; methoxylated quercetin 200 ppm) with 4 replicates and 10 birds per replicate. Birds were reared for 35 days and their feed intake and weight gain were measured weekly. At 35d, eight birds of average weight from each replicate were selected for blood collection and analysis. Weight gain of birds in the groups fed quercetin was higher when compare to NC but there was no significant difference. In the serum, creatinine, BUN and AST in quercetin groups significantly decreased compared to those of control (NC and PC) (P<0.05). The contents of IgA and IgM were significantly lower in quercetin groups than those of NC (P<0.05). SOD like activity and MDA content tended to decrease in quercetin groups, however, there was no significant difference among treatments. In conclusion, supplemental quercetin to poultry diet could be positive aspect on performance and blood metabolites. Optimum adding levels was more than 20 ppm.

• Horticultural Science & Technology
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• v.33 no.6
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• pp.891-899
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• 2015

The lily symptomless virus (LSV) is the most common virus in Korean native lilies and causes various types of damage to overall plant growth. This study was carried out to investigate the elimination rate of the LSV by the in vitro scale culture (scaling) method in Korean native lilies and to test reinfection rates of the LSV under several field culture conditions of bulb production. Four Korean native lilies (Lilium dauricum, L. distichum, L. lancifolium, and L. maximowitzii) were used and their scales were cultured in vitro for micro-scale formation. The micro-scales were subcultured repeatedly using MS culture medium supplemented with 30 or $90g{\cdot}L^{-1}$ sucrose. The culture conditions were $24{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ PPFD with 16 hour daylength using fluorescent lamps and maintained at $22{\pm}2^{\circ}C$. The virus-free bulblets were grown for one to three years in the greenhouse and transplanted to the field in October or March. Virus infection rates were investigated by direct tissue blotting immunobinding assays and measurement of chlorophyll and protein contents. Virus-free plants could be obtained from the 5th subculture of micro-scales in L. lancifolium and L. maximowitzii or from primary culture in L. dauricum and L. distichum. LSV-free plants were reinfected during bulb production in the field. Reinfection rates were higher at older bulb ages and under higher planting density. The plants planted in October and at inland Gyeongsan had higher infection rates than those planted in March and at coastal area Pohang. The reinfection rate of L. maximowitzii was higher than those of L. dauricum and L. lancifolium. The LSV-infected plants had lower chlorophyll contents and unchanged protein contents compared to virus-free plants.