• Journal of The Korean Society of Grassland and Forage Science
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• v.22 no.4
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• pp.265-272
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• 2002

Forage breeding laboratory of National Livestock Research Institute, R.D.A. has made interspecific hybrids of Lolium multiflorum $\times$ L. pratensis and intergeneric hybrids of Lolium $\times$ Festuca since 1984, and has collected ecotypes of Italian ryegrass since 1991. Growth characteristics of these hybrids and ecotypes were researched, and then these clone lines were named. Among these clone lines, the several clones that have polen fertility, high cold-tolerance, and similar heading time were used for making synthetics, Naehan 6, 7, 8, 9, with polycrossing method in 1997. Field experiments were carried out to compare the mophological and agronomical characteristics and forage productivity and quality of the synthetics with those of Italian ryegrass varieties, Barmultra and Hwasan 101. in Suwon and Yonchun from 1999 to 2000. Heading time of the synthetics were 22th to 24th May that belong to late-mature types to be similar to that of Barmultra and Hwasan 101 in Suwon. The synthetics were 101 to 106 c3n in plant length, medium or thick in thickness of stem, dark peen in leaf color, broad and long in flag leaf, strong in lodging resistance, and excellent in regrowth. Winter survivals of the synthetics were no different from that of Barmultra or Hwasan 101 in Suwon, but better than that of Barmultra or Hwasan 101 in Yonchun where was -10 to -12$^{\circ}C$ of minimum average air temperature in January or February. Dry matter(DM) yields of the synthetics were similar to DM 8,238kg per ha of Barmultra in Suwon, but in Yonchun, were more 7 to 13% than DM 7,291kg per ha of Barmultra. Forage qualities, IVDMD, ADF, NDF and TDN of the synthetics were lower than those of Hwasan 101, but higher than those of Barmultra.

• Journal of Korea Game Society
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• v.4 no.4
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• pp.11-18
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• 2004

The on-line games in the past were played by only two persons exchanging data based on one-to-one connections, whereas recent ones (e.g. MMORPG: Massively Multi-player Online Role-playings Game) enable tens of thousands of people to be connected simultaneously. Specifically, Korea has established an excellent network infrastructure that can't be found anywhere in the world. Almost every household has a high-speed Internet access. What made this possible was, in part, high density of population that has accelerated the formation of good Internet infrastructure. However, this rapid increase in the use of on-line games may lead to surging traffics exceeding the limited Internet communication capacity so that the connection to the games is unstable or the server fails. expanding the servers though this measure is very costly could solve this problem. To deal with this problem, the present study proposes the load distribution technology that connects in the form of local clustering the game servers divided by their contents used in each on-line game reduces the loads of specific servers using the load balancer, and enhances performance of sewer for their efficient operation. In this paper, a cluster system is proposed where each Game server in the system has different contents service and loads are distributed efficiently using the game server resource information such as CPU utilization. Game sewers having different contents are mutually connected and managed with a network file system to maintain information consistency required to support resource information updates, deletions, and additions. Simulation studies show that our method performs better than other traditional methods. In terms of response time, our method shows shorter latency than RR (Round Robin) and LC (Least Connection) by about 12%, 10% respectively.

• Journal of Music and Human Behavior
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• v.1 no.1
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• pp.1-10
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• 2004

Being engaged in the musical tasks needs cognitive skills to perceive musical sound, organize them into meaningful unit, store them in the memory and retrieve them when needed. These skills are also required for academic tasks indicating that there is positive correlation between skills for musical and academic tasks. Based on these findings, the study purported to examine whether the developed sessions can enhance cognitive skills which is composed of auditory information skills, which is composed of perceiving sounds, organizing them into groups based on the existing information or organization pattern, and short-term memory skills. Eighteen elementary students in 4, 5, and 6th grades have participated in the study. The study has administered Music Cognitive Skills Test(MCST) before and after implementing music therapy sessions. The MCST consisted of five parts, first one measuring the rhythm imitating skills, second, measuring the melodic imitation skills, third, measuring discriminative skills in identifying higher pitch, fourth, measuring discriminative skills in identifying identical chords, and lastly, measuring the tone retention skills. The results indicated that there was statistical difference between the pre and post test in rhythm and melody imitation skills. Because reproduction of perceived rhythm patterns requires memory skills, imitating patterns are considered cognitive skills. Also melody is defined adding spatial dimension to the rhythm which is temporal concept. Being able to understand melodic pattern and to reproduce the pattern also requires cognitive skills. The subjects have shown significant improvement in these two areas. In other areas, there were definite increase of scores, however, no significant differences. The study also explores interpretation of these results and also observed consistencies among the participants in completing the musical tasks.

• Research in Plant Disease
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• v.10 no.3
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• pp.188-193
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• 2004

The symptom expressions such as yellowish and mosaic spots in overwintering barley have been considered to be a damage by cold or water. However, it had revealed that the symptom expressions were caused by viruses throughout three year nationwide surveys. Barley yellow mosaic virus (BaYMV), Barley mild mosaic virus (BaMMV), and Soil-borne wheat mosaic virus (SBWMV) was detected in 2001-2003 and Barley yellow dwarf virus-MA V (BYDV -MA V) from field samples collected on March in 2003. The results of investigation showed that the incidence of BaYMV was more than 70％ and that of BaMMV and SBWMV was 15.7-37.4％ and 0.7-10.1 ％ in three year surveys, respectively. The incidence of BYDV-MAV was approximately 1 ％ in 2003 only. The distribution of BaYMV was relatively uniform throughout barley fields in Korea, but the incidence of the virus in Gyunggi Province was as low as 19％ compared to 65-85％ in the rest of regions. On the other hand, 70％ of BaMMV was found to be in the west south regions of Korea, Jeonbuk and Jeonnam Provinces. Taken together, both BaYMV and BaMMV were thought to be dominant casual agents in overwintering barley by either single or mixed infections. Previous survey data for BaYMV from 1994 to 1996 indicated that the incidence of the virus was approximately 40％ in Jeonbuk, Jeonnam, and Gyungnam Provinces. Thus, comparing with the results from the recent nationwide survey, the incidence of BaYMV had been rapidly increasing in overwintering barley fields in the southern part of Korea.

• Journal of Animal Science and Technology
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• v.52 no.4
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• pp.305-312
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• 2010

Seventy two Hanwoo steers in final fattening period ($585.87{\pm}41.02kg$) were randomly assigned to 3 groups, LPLT (relatively low protein and low energy; CP 12%, TDN 73%), LPHT (relatively low protein and high energy; CP 12%, TDN 75%) and HPHT (relatively high protein and high energy; CP 14%, TDN 75%) in concentrate feed for 163 days in order to investigate the effects on growth performance, carcass characteristics, and longissimus dorsi muscle's chemical compositions. Rice straw was also fed as a roughage. Because ADGs were higher in LPLT and HPHT than LPHT, feed efficiencies were improved in LPLT and HPHT group (P<0.05). Feeding concentrates with different CP and TDN levels had affected to improve back fat thickness and rib eye area in HPHT group but had no effect on carcass weight and meat yield index. Carcass weight for LPLT, LPHT and HPHT were $420.75{\pm}30.56$, $417.05{\pm}32.03$ and $418.32{\pm}32.03kg$, respectively. Meat quality grade was improved in HPHT (P<0.001), because the marbling score was highest in HPHT group. Auction prices (carcass/kg) of LPLT, LPHT and HPHT group were 17,904 won, 18,094 won and 18,899 won, respectively. The percentage of animals over grade 1 appeared in LPLT, LPHT and HPHT were 79.2, 72.7 and 90.8%, respectively. The results of chemical analysis of longissimus dorsi muscle showed no difference between groups but crude fat composition tended to be higher in HPHT group (P=0.088) than the other groups. Stearic acid contents in the muscle was significantly increased in HPHT group than LPLT group (P<0.05). Myristoleic acid and oleic acid composition in HPHT group was higher than LPLT and LPHT group. These results supported the hypothesis that supplementation of higher levels of crude protein and energy in concentrates to Hanwoo steers' during final fattening period improved the growth performance and the carcass quality grade.

• Journal of Food Hygiene and Safety
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• v.32 no.3
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• pp.187-192
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• 2017

The consumption of herbal medicines has been increasing with growing interest in health. However, due to recent climate change and the complex distribution process of herbal medicines with high import dependence the likelihood of contamination with mycotoxin has been increased. Mycotoxins are emerging as key indicators for ensuring safety of herbal medicines. A total of 498 herbal medicine samples were screened for mycotoxin contamination in this study. Aflatoxin in the herbal medicine samples was extracted by using immunoaffinity column, then the extracted aflatoxin was quantified via high performance liquid chromatography coupled with fluorescence detection (HPLC-FLD) method. The extraction method was verified by linearity, recovery, LOD and LOQ. Aflatoxins were detected in 39/498 samples in an average of $7.670{\mu}g/kg$ ($0.610-77.452{\mu}g/kg$ range). Although safety standards for Corydalis Tuber is not currently available in korea, five of the 39 samples had high concentration of aflatoxins (average of $14.9{\pm}4.1{\mu}g/kg$). In conclusion, it is urgent to establish safety criteria of aflatoxin in Corydalis Tuber. The results of the current study suggest that continuous monitoring is necessary for proactive management of herbal medicine safety.

• The Korean Journal of Pesticide Science
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• v.10 no.2
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• pp.124-130
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• 2006

Rice plant extracts of brown planthopper (BPH) resistant rice varieties, Jangseongbyeo (JSB) and Hwacheongbyeo (HCB) at different growth stages (seedling, tillering, heading and ripening) were sequentially fractioned using hexane, ethyl ether, ethyl acetate, butanol, and distilled water. The extracts were applied to BPH susceptible rice variety, Dongjjnbyeo (DJB), to investigate the insecticidal and repellent effects against BPH. BPH insecticidal effects were not clearly observed with almost all of the extract fractions obtained from both JSB and HCB varieties for 12 h, whereas the ethyl ether and hexane extract fractions showed about 10 to 30% of BPH mortality in 24 to 48 h of application periods. An effective BPH repellent activity was found with the applications of ethyl ether extract fractions obtained from JSB variety. The extract fractions obtained from HCB variety did not show any different repellence among the various fractions. The BPH repellent effects of the extract fractions obtained at different growth stages of either JSB or HCB varieties did not show any correlations. The effect of ethyl ether fraction on BPH repellent was continually increased by 30 h after treatment and thereafter decreased. In addition, the first sub-fraction separated by a flash column chromatography eluted with chloroform:methanol (9:1, v/v) from the BPH effective ethyl ether faction in JSB variety might be meaningful to repel BPH from BPH susceptible target rice plants. The results indicated that the ethyl ether fraction obtained from JSB was higher in repellent activity than in insecticidal activity, and suggesting that there might be specific substance(s) in the first sub-fraction (sF1) of the ethyl ether fraction in JSB that could provide repellent activity against BPH.

• The Transactions of the Korea Information Processing Society
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• v.5 no.10
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• pp.2575-2583
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• 1998

The productionof the highly relible softwae systems and theirs performance evaluation hae become important interests in the software industry. The software evaluation has been mainly carried out in ternns of both reliability and performance of software system. Software reliability is the probability that no software error occurs for a fixed time interval during software testing phase. These theoretical software reliability models are sometimes unsuitable for the practical testing phase in which a software error at a certain testing stage occurs by causes of the imperfect debugging, abnornal software correction, and so on. Such a certatin software testing stage needs to be considered as an outlying stage. And we can assume that the software reliability does not improve by means of muisance factor in this outlying testing stage. In this paper, we discuss Bavesian software reliability growth modeling and estimation procedure in the presence of an imidentitied outlying software testing stage by the modification of Jehnski Moranda. Also we derive the Bayes estimaters of the software reliability panmeters by the assumption of prior information under the squared error los function. In addition, we evaluate the proposed software reliability growth model with an unidentified outlying stage in an exchangeable model according to the values of nuisance paramether using the accuracy, bias, trend, noise metries as the quantilative evaluation criteria through the compater simulation.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.4
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• pp.602-612
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• 2010

This study was conducted to investigate the state of hygiene education aimed for by bakers, and the evaluations of the importance and the performance concerning sanitary characteristics by the bakers. The questionnaires were administered to 186 bakers in Busan and the data evaluated by 5 scales method of Likert were statistically analyzed. 20.4% of bakers have not received hygiene education. Only 32.8% of bakers have experienced hygiene education regularly. The more the bakers were educated, the more they practiced the contents of hygiene education. The major reason of education unfulfilment was due to insufficient equipments and facilities. The scores of the hygienic performance of educated bakers were significantly (p<0.05) higher than those of uneducated bakers in food sanitation, especially for sanitary characteristics on inspection, pre-preparation and distribution. The mean scores of the importance and the performance evaluated by bakers were 4.05/5.00 and 3.76/5.00, respectively. The bakers assessed the highest scores on the importance and the performance of personal hygiene. The gap score was -0.30 between the importance and the performance for sanitary characteristics. The baker recognized that sanitary management was not performed as much as they recognized its importance. The importance and the performance grid of bakers revealed that the items of checking the certification for the origin of new food ingredient, inspecting deliveries as quickly as possible, separation between preparing and breading time, thawing frozen food under running tap water/in refrigerator, separating disposal gloves and utensils by the purpose, putting products in cleaned and sterilized utensils, letting consumes know the expiration date of products, preventing a rubber hose from being left on the kitchen floor, checking insect nets frequently and so on showed lower scores compared to the mean scores of the importance and the performance. The levels of the hygienic performance by bakers were positively correlated (p<0.01) with the recognitions of the importance on sanitary characteristics. These results might provide basic data for hygienic training and play a role on the improvement of the sanitary management in bakery.

• Journal of Bio-Environment Control
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• v.26 no.4
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• pp.340-345
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• 2017

Carrot leaves have many nutrients as well as roots, which will increase the demand for carrot leaves in the future. This study was carried out by dividing into two stages: high temperature and low temperature periods, in order to investigate the possibility of cultivation of carrot leaves and the composition and EC of the nutrient solution for growth and quality of carrot leaves. Composition of nutrient solution($NO_3-N:16.0$, $NH_4-N:1.0$, P: 1.0, K: 11.0, Ca: 2.0, Mg: 1.0, $SO_4-S:1.0mM{\cdot}L^{-1}$) developed by analysis of plant. In the high temperature range (From June $29^{th}$ to Sep. $8^{th}$, 2016), the concentration of the developed nutrient solution (JNU) were 1.0, 2.0, 3.0, and $4.0dS{\cdot}m^{-1}$ and the concentration of nutrient solution of Japanese Horticultural Station(JHS) $2.0dS{\cdot}m^{-1}$ was used for comparison. In the low temperature range (From Dec. $31^{st}$, 2015 to Feb. $29^{th}$, 2016), the concentration of the developed nutrient solution 1.0, 2.0, and $3.0dS{\cdot}m^{-1}$ were used. Growth was investigated in root fresh and dry weights, shoot fresh and dry weights, leaf number, and leaf area of carrot. In the high temperature range, the leaf area and shoot fresh and dry weights were good at 1.0 and $2.0dS{\cdot}m^{-1}$. The sugar content of the root was the highest at the EC $2.0dS{\cdot}m^{-1}$, and the chlorophyll content was the highest at the EC $4.0dS{\cdot}m^{-1}$. In the low temperature range, The shoot fresh and dry weights were the highest at EC 1.0 and $2.0dS{\cdot}m^{-1}$. There was no significant difference in sugar content and chlorophyll content. As a result, from the viewpoint of growth and quality of carrot, it is good to cultivate EC 1.0 and $2.0dS{\cdot}m^{-1}$ in high temperature period and low temperature period, but EC $1.0dS{\cdot}m^{-1}$ is economical perspective such as fertilizer input.