• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.4A
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• pp.332-340
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• 2010

In this paper, we deal with multi-user diversity scheduling methods that transmit simultaneously signals from multiple users using superposition coding multiplexing. These methods can make various scheduling methods be obtained, according to strategies for user selection priority from the first user to the first-following users, strategies for per-user power allocation, and resulting combining strategies. For the first user selection, we consider three strategies such as 1) higher priority for a user with a better channel state, 2) following the proportional fair scheduling (PFS) priority, 3) higher priority for a user with a lower average serving rate. For selection of the first-following users, we consider the identical strategies for the first user selection. However, in the second strategy, we can decide user priorities according to the original PFS ordering, or only once an additional user for power allocation according to the PFS criterion by considering a residual power and inter-user interference. In the strategies for power allocation, we consider two strategies as follows. In the first strategy, it allocates a power to provide a permissible per-user maximum rate. In the second strategy, it allocates a power to provide a required per-user minimum rate, and then it reallocates the residual power to respective users with a rate greater than the required minimum and less than the permissible maximum. We consider three directions for scheduling such as maximizing the sum rate, maximizing the fairness, and maximizing the sum rate while maintaining the PFS fairness. We select the max CIR, max-min fair, and PF scheduling methods as their corresponding reference methods [1 and references therein], and then we choose candidate scheduling methods which performances are similar to or better than those of the corresponding reference methods in terms of the sum rate or the fairness while being better than their corresponding performances in terms of the alternative metric (fairness or sum rate). Through computer simulations, we evaluate the sum rate and Jain’s fairness index (JFI) performances of various scheduling methods according to the number of users.

• Journal of Veterinary Clinics
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• v.21 no.4
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• pp.329-335
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• 2004

Dog spermatozoa were recovered from the caudae epididymides of 23 domestic dogs which were 11 pure breed and 12 mix-breed dogs ranging in age from 0.6 to 3 years. The experimental designs were as follows: 1) the effect of chilling to 0. 10 or 37$^{\circ}C$. 2) the kinetics of chilling injury at 0 or 4$^{\circ}C$, and 3) the effect of sugars at $0^{\circ}C$. Viable spermatozoa were recovered by percoll gradient separation and adjusted to 5${\times}$10$^{7}$ spermatozoa/ml. In experiment 1, spermatozoa were diluted with 0.33 M glucose supplemented with 3% BSA (G-BSA) at 1:2 dilution. Spermatozoa were loaded into straws and exposed at 0, 10 or 37$^{\circ}C$ for 30 min. In experiment 2, spermatozoa were prepared as the experiment 1 and exposed for 0.5, 5, 15, or 30 min at 0 or 4$^{\circ}C$. In experiment 3, spermatozoa were diluted with different sugars (0.33 M galactose, glucose, fructose, mannitol, lactose, sucrose, raffinose) and cooled to $0^{\circ}C$ for 30 min. Sperm membrane integrity, motility and acrosome integrity were assayed after rewarming at 37$^{\circ}C$ for 5 min. Sperm motility and membrane integrity abruptly decreased with decreasing temperature but acrosome integrity gradually decreased (P<0.05). Sperm motility was more sensitive to cold shock than membrane integrity and acrosome integrity. Spermatozoa cooled to $0^{\circ}C$ were more damaged than those at 4$^{\circ}C$. Sperm motility was not different among exposed times at both. 0 and 4$^{\circ}C$. However, membrane integrity of spermatozoa exposed for 30 min at both 0 and 4$^{\circ}C$ was significantly lower (P<0.05). Spermatozoa diluted in 0.33 M fructose or galactose showed lower motility and higher morphological abnormality with coiled tail at $0^{\circ}C$. These sperm characteristics were strongly related. These results indicate that dog epididymal spermatozoa are relatively sensitive to rapid cooling and higher morphological abnormality at $0^{\circ}C$ was shown in spermatozoa diluted in fructose and galactose.

• Journal of dental hygiene science
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• v.16 no.2
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• pp.150-156
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• 2016

In this study, the surface treatment of a self-cured temporary crown was polished using a denture bur, silicone bur, or pumice. The color stability of the temporary crown resin specimen was evaluated by immersing it in coffee, and cola, wine, beer, red pepper paste, or soybean paste. Two-hundred eighty-five identical resin specimens with six types of staining solution and three types of surface treatment were placed in a shaking incubator at $37^{\circ}C$. The degree of discoloration was observed using a time-lapse recording of days 1, 5, and 7. $L^*$, $a^*$, and $b^*$ were measured using a spectrophotometer, which shows the quantitative value of discoloration, and statistically processed after calculating ${\Delta}E^*$. The results show that as time passed, all the specimens showed a color change (p<0.001). The amount of color change was the greatest in in crowns with denture bur polishing on the day 1, 5, and 7. As the precipitation time increased, the ${\Delta}E^*$ value was also increased. Of the specimens immersed on day 1, the greatest color change in crowns polished with denture bur was observed in those immersed in red pepper paste, while the smallest color change was observed in those immersed in cola. On days 5 and 7, the greatest color change in crowns polished with denture bur was observed in those immersed in red wine. Crowns polished with silicone bur and immersed in soybean paste exhibited the smallest color change. Based on the results, compared to pumice polishing, silicone bur polishing results in better color stability, saves time and money, and is recommended for patients with temporary crowns.

• Korean Journal of Plant Resources
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• v.10 no.4
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• pp.401-410
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• 1997

This experiment was conducted to investigate the opimum media, media amount and planting density of nutri-culture for the high quality and yield of wild vegetable, Liguliaria fischeri Turez. The fried rice hull was recognized best media among perlite, sand and fried rice hull for nutri-culture of Ligularia fischeri Turcz. The yield on fried rice hull media at early growing stage was lower, but higher than in other media at late growing stage. Therefore, total yield in fried rice hull media was 15-29% higher than that of the existing perlite media. Growth and yield of Ligularia fischeri Turcz. were not significantly different between medium amounts, therefore considering economical efficiency and stability, the optimum medium amount was 105 $\iota/m^3$, Yield by planting density increased in the high density and 50 plants/$m^2$ was considered as proper planting density in nutri-culture of Liguliaria fishcheri Turcz.

• The Korean Journal of Zoology
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• v.32 no.4
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• pp.337-350
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• 1989

In this study, we compared patterns of hemolvmph with ovarian proteins during the yolk formation of Gewis paludum by using SDS/polyacrylamide gel electrophoresis and he dimen-tlonal electrophoresis. In addition, we examined patterns of glycoprotein which were composed of yolk substances. The results were as follows: The protein patterns in ovary of the 5th instar without eggs were similar to those of adult after ovulation. Protein amounts of the ovaw without developing eggs were less than those of the ovaw containing oocvtes or matured eggs at the molecular weights range from 66, 000 to 110.000 daltons. No glvcoproteins were observed in ovaw without eggs. But the glvcoproteins were gradually increased according to development of eggs in the 5th instar. After the ovulated ovaw of adult, no glvcoprotein bands urere occurred as the bands of the ovary without eggs in the 5th instar. Also, amounts of hemolvmph protein between 66, 000 and 110, 000 in molecular weight were increased during yolk formation of the 5th instal. The results suggest that ovarian protein substances may originate from hemolpnph. In the 5th instar, the amounts of glycoprotein of developing eggs was gradually increased in the hemolymph. The band of M.W. 29, 500 was occurred in the hemolpnph of the 5th instar and adult without eggs. This protein mal be precursor of glvcoprotein in the high molecular weight area in the ovary of more developed eggs. The number of spots and the amounts of protein in ovary without eggs were less than those of ovary containing eggs by two dimensional elec-trophoresis. The protein bands between 45, 000 and 110, 000 almost appeared in acidic field of he dimensional gel. Especially, the band, M.W. 109, 000, uras separated 3 spots, a1, a2, and as. The band, M.W. 102, 000, has spots which designated b1, b2, b3, and b4. Besides, proteins below M.W. 24, 000 were occurred less spots in the basic field than those of acidic field. The mechanism of intracellular organs (= cell organells) uras related to the yolk protein synthesis of oocyte in the process of yolk protein formation of derris pcfudum.

• Fire Science and Engineering
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• v.17 no.1
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• pp.8-20
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• 2003

Natural gas has been supplied through underground pipelines and valve stations as a new city gas in Seoul. In contrast to its handiness the natural gas has very substantial hazards due to fires and explosions occurring from careless treatments or malfunctions of the transporting system. The main objectives of this study are to identify major hazards and to perform risk assessments after assessing reliabilities of the composing units in dealing with typical pipeline networks. there-fore two method, fault tree analysis ;1nd event tree analysis, are used here. Random valve stations are selected and considered its situation in location. The value of small leakage, large rupture, and no supply of liquefied natural gas is estimated as that of top event. By this calculation the values of small leakage are 3.29 in I)C valve station, 1.41 in DS valve station, those of large rup-lure are $1.90Times10_{-2}$ in DC valve station, $2.32$\times$10^{-2}$ in DS valve station, and those of no supply of LNG to civil gas company are $2.33$\times$10 ^{-2}$ , $2.89$\times$10^{-2}$ in each valve station. And through minimal cut set we can find the parts that is important and should be more important in overall system. In DC valve station one line must be added between basic event 26,27 because the potential hazard of these parts is the highest value. If it is added the failure rate of no supply of LNG is reduced to one fourth. In DS valve station the failure rate of basic event 4 is 92eye of no supply of LNG. Therefore if the portion of this part is reduced (one line added) the total failure rate can be decreased to one tenth. This analytical study on the risk assessment is very useful to prepare emergency actions or procedures in case of gas accidents around underground pipeline networks and to establish a resolute gas safety management system for loss prevention in Seoul metropolitan area.

• Korean Journal of Agricultural and Forest Meteorology
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• v.14 no.3
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• pp.132-141
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• 2012

Climate change impact assessment of cereal crop production in South Korea was performed using land attributes and daily weather data at a farm scale as inputs to crop models. Farmlands in South Korea were grouped into 68 crop-simulation zone units (CZU) based on major mountains and rivers as well as existing land use information. Daily weather data at a 1-km grid spacing under the A1B- and RCP8.5 scenarios were generated stochastically to obtain decadal mean of daily data. These data were registered to the farmland grid cells and spatially averaged to represent climate conditions in each CZU. Monthly climate data for each decade in 2001~2100 were transformed to 30 sets of daily weather data for each CZU by using a stochastic weather generator. Soil data and crop management information for 68 CZU were used as inputs to the CERES-rice, CERE-barley and CROPGRO-soybean models calibrated to represent the genetic features of major domestic cultivars in South Korea. Results from the models suggested that the heading or flowering of rice, winter barley and soybean could be accelerated in the future. The grain-fill period of winter barley could be extended, resulting in much higher yield of winter barley in most CZUs than that of rice. Among the three major cereal grain crops in Korea, rice seems most vulnerable to negative impact of climate change, while little impact of climate change is expected on soybeans. Because a positive effect of climate change is projected for winter barley, policy in agricultural production should pay more attention to facilitate winter barley production as an adaptation strategy for the national food security.

• The Korean Journal of Pesticide Science
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• v.11 no.2
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• pp.106-116
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• 2007

Pesticide, chlorfluazuron was subjected to determine the safety of terminal residues at the harvesting date of perilla leaves cultivated in plastic house. After the pesticide applied on a foliar spray in 2005 and 2006, leaf persistence of its residue was analysed for 10 days before leaf harvest. The degradation rate of chlorfluazuron in the leaf was 32.3 %(standard application), 43.6 %(double application) and 78.0 %(standard), 80.4 %(double) at second and tenth day, respectively, under analysis of GC/ECD in 2005. The degradation rate of chlorfluazuron in the leaf was 33.1 %(GC/ECD analyze), 34.0 %(HPLC/UVD analyze) and 77.9 %(GC/ECD), 78.4 %(HPLC/UVD) at second and tenth day, respectively, under the standard level of pesticide in 2006. The biological half-life of the chlorfluazuron residue was estimated by the regression equation calculated from daily dissipation of pesticide in the perilla leaves. The longest half-life of the chlorfluazuron residue in perilla leaves was 5.5 days. The maximum residual limit(MRL) for chlorfluazuron based on the longest half-life was estimated 2.0ppm at harvesting day, 2.5ppm at second day and 7.1ppm at tenth day before leaf harvesting of perilla.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.1
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• pp.109-116
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• 2008

In this study, the breads with medicinal herbs (MH) composites showing immunostimulating activity were prepared and their characteristics were examined. Fourteen kinds of medicinal herbs were extracted with hot water and divided into 3 groups (MH-1, MH-2, MH-3) based on their contents. All groups showed immunostimulating activity in terms of macrophage phagocytosis, nitrite production, cytostatic activity and cytokine production. In the preparation of breads containing MH extracts of various contents (0, 30, 50, 70, and 100%), there was no significant difference among dough pHs of all groups after first fermentation, but loaf volume was significantly (p<0.05) increased in 70% added group while decreased in 30%, 50%, and 100% added groups compared to the control. The "a" and "b" values of bread crumb increased with the content of MH extracts while "L" value decreased, but these values of bread crust were similar to the control group. Most improvements in hardness, adhesiveness, gumminess and chewiness of bread were noticed by the addition of 70% MH extracts, but those of springiness, cohesiveness and resilience were mostly by the 50% addition ones. Through the sensory evaluation, it was revealed that mouth feeling, taste and overall preference decreased at breads containing 70% and 100% extracts, although appearance and crumb texture were not significantly (p<0.05) different among all groups.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.2
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• pp.343-350
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• 2002

This study was conducted to standardize the manufacturing process of doenjang. The preparation methods, kinds and levels of the ingredients were determined by the statistical surveys of literatures obtained from cooking books, scientific papers and doenjang manufacturing factories. The standardized preparation of fermentation methods of doenjang were classified into two large groups, that were traditional and modified (commercialized) methods. Most soybeans used in doenjang preparation were the large size. To prepare traditional doenjang, soybeans were cleaned, scaled and cooked for 2 hrs at atmospheric pressure. These cooked soybeans were crushed in water and molded as brick shape. The molded soybean was dried for 2 days in the air, hung up by rice straw and fermented for 30~60 days under natural environmental condition (called meju). Recently soybean grain meju that inoculated with Asp. oryzae also frequently used to make traditional doenjang. The fermented meju was brined with a ratio of meju : salt : water = 18.4 : 14.6 : 67.0 and the meju-brine mixtures were ripened for 2 months. When the meju-brine mixture was fully fermented, it was separated into liquid and solid parts. The crushed solid part was further ripened in a separated pottery for 60 days and become doenjang. The liquid part was filtered, boiled and used as soy sauce. In modified commercial doenjang preparation, soybeans were cocked by autoclaving and then cooled about to 3$0^{\circ}C$. Separately, steamed barley grains or wheat flour were inoculated with 0.2% Asp. oryzae and incubated for 3 days at 3$0^{\circ}C$ and mixed with the crooked soybeans, salt, and water (soybean : salt : starch : water = 39.8 : 12.5 : 22.6 : 25.1). These mixtures were ripened for 30 days at 3$0^{\circ}C$. It seems that the manufacturing process of traditional doenjang needs to be more industrialized, whereas, the commercial doenjang preparation is going to adapt the traditional processing method of doenjang.