• Journal of Life Science
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• v.22 no.8
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• pp.999-1008
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• 2012

The circadian clock is a self-sustaining 24-hour timekeeper that allows organisms to anticipate daily-changing environmental time cues. Circadian clock genes are regulated by a transcriptional-translational feedback loop. In Arabidopsis, LATE ELONGATED HYPOCOTYL (LHY) and CIRCADIAN CLOCK-ASSOCIATED 1 (CCA1) transcripts are highly expressed in the morning. Translated LHY and CCA1 proteins repress the expression of the TIMING OF CAB EXPRESSION 1 (TOC1) transcripts, which peaks in the evening. The TOC1 protein elevates the expression of the LHY and CCA1 transcripts, forming a negative feedback loop that is believed to constitute the oscillatory mechanism of the clock. In mammals, the transcription factor protein CLOCK, which is a central component of the circadian clock, was reported to have an intrinsic histone acetyltransferase (HAT) activity, suggesting that histone acetylation is important for core clock mechanisms. However, little is known about the components necessary for the histone acetylation of the Arabidopsis clock-related genes. Here, I report that DET1 (De-Etiolated1) functions as a negative regulator of a key component of the Arabidopsis circadian clock gene LHY in constant dark phases (DD) and is required for the down-regulation of LHY expression through the acetylation of histone 3 (H3Ac). However, the HATs directly responsible for the acetylation of H3 within LHY chromatin need to be identified, and a link connecting the HATs and DET1 protein is still absent.

• Journal of Embryo Transfer
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• v.18 no.2
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• pp.143-149
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• 2003

This study was carried out to cryopreserve and to investigate characteristics of semen in Hanwoo. Semen was obtained from bulls selected by Daekwanryeong Branch station. Semen was collected each morning of the experiment, placed in water jacketed tubes at 37$^{\circ}C$, and trans-ported to the research laboratory within 10 minutes. Semen was extended with Egg yolk-glycerol extender to contain 50${\times}$10$^{6}$ sperm/ml. Semen was cooled over a 6h period in water jacketed tubes from about 25 to 5$^{\circ}C$, Egg yolk-glycerol extender was added in one step at 5$^{\circ}C$. Semen was aspirated into 0.5ml straws, which were sealed with powder. Egg yolk-glycerol extender, which is used in Hanwoo sperm frozen and stored, semen from 13 Hanwoo bulls collected, the postthawed percentages of motile sperm were 65.7%. In semen characteristics of Hanwoo bulls, number of bulls volume are 5.7 ml and total cell count are 975${\times}$10$^{6}$ m1 ejaculate.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.37 no.2
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• pp.85-94
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• 2001

The vertical distribution and activity patterns of fishes during the evening and morning transitions were investigated acoustically and by pelagic trawling on October 2-10, 1997 in the Korean Eastern Sea. The acoustic data were collected from four stations with a scientific echo sounder operating at a frequency of 38 kHz, and the echogram was used to analyze the diel vertical migration of fish. Biological sampling was accomplished by pelagic trawling to identify fish species recorded on the echograms, and the species and length compositions were investigated. Vertical profiles of water temperature, salinity at the trawl station were taken with a CTD system and were related to the diel movement and the depth distribution of fish. During the day, one group of fish mainly distributed above the depth layer of 50 m, the other group was at deeper water, approximately 250 m, but began to migrate toward the surface before sunset with a time difference. During the night, they were dispersed between the surface and the depth of 125 m. Just prior to sunrise, the scattering layer was divided with 2 groups and began to migrate downwards, respectively. Several trials of pelagic trawling for scattering layers suggest that the most dominant scatterer in the survey area of this study was Japanese flying squid, Todarodes pacificus..

• Journal of Korean Society of Transportation
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• v.27 no.1
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• pp.143-155
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• 2009

A dynamic traffic assignment (DTA) has recently been implemented in many practical projects. The core of dynamic model is the inclusion of time scale. If excluding the time dimension from a DTA model, the framework of a DTA model is similar to that of static model. Similar to static model, with given exogenous travel demand, a DTA model loads vehicles on the network and finds an optimal solution satisfying a pre-defined route choice rule. In most DTA models, the departure pattern of given travel demand is predefined and assumed as a fixed pattern, although the departure pattern of driver is changeable depending on a network traffic condition. Especially, for morning peak commute where most drivers have their preferred arrival time, the departure time, therefore, should be modeled as an endogenous variable. In this paper, the authors point out some shortcomings of current DTA model and propose an alternative approach which could overcome the shortcomings of current DTA model. The authors substitute a traditional definition for time-dependent OD table by a new definition in which the time-dependent OD table is defined as arrival time-based one. In addition, the authors develop a new DTA model which is capable of finding an equilibrium departure pattern without the use of schedule delay functions. Three types of objective function for a new DTA framework are proposed, and the solution algorithms for the three objective functions are also explained.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.40 no.2
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• pp.167-175
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• 2020

The Two-fluid Model, proposed by Herman and Prigogine in 1979, is a macroscopic model for describing network operability in urban networks. Since the Two-fluid Model parameters change according to the traffic flow characteristics, it is necessary to identify the cause of flow change when analyzing the operability using the parameters. This study compared the crash risk according to rainfall using the Two-fluid Model parameters, and explained that the driving behavior affects the operability of the urban network. The results of the parameters estimation showed poor network operation under rainfall condition. The factors of drivers' crash risk perception model were calculated, and driving behavior was analyzed due to crash risk according to rainfall. In both the morning and evening, drivers tended to slow down their speeds to reduce the crash risk, because the risk on rainy days could be high when the speed was the same as on a sunny days. However, the crash risk was still higher on rainy days than sunny. In the future, it is necessary to analyze the relationship between the network operation and the crash risk in various networks and to improve both.

• Journal of Animal Science and Technology
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• v.46 no.4
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• pp.517-524
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• 2004

The objective of this study was to investigate the environmental effects on duration time of milk flow, peak milk flow, and average milk flow in teats, and to estimate their relationships with milk yields in morning and evening milking, and to provide fimdamental information for the further study on their relationships with clinical mastitis and somatic cell in milk. A total of 6,768 milking records were studied in 72 Holstein cows. The influences of season, parity, lactation month, and milking interval on characteristics of milk flow considering in linear model were significant(p<.05). Duration of milk flow was longest at milking in fall, past first parity and second month of lactation, and with milking interval over than 13.5hrs. Average milk flow rate and peak milk flow rate were highest at milking in summer, past first parity and 8${\sim}$10 months of lactation, and with milking interval over than 13.5hrs. Milk flow rate was positively correlated to milk yield, and negatively correlated to the duration of milk flow. However duration milk flow was positively correlated to the milk yield with high level of correlation coefficient(+.60). For the establishment of optimum selection criteria on these traits, other aspects such as the udder health, disease and respective economic weights of milk flow characteristics in this study must be considered to develop the indices.

• Journal of Animal Science and Technology
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• v.53 no.5
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• pp.475-480
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• 2011

This study was conducted to investigate the effects of different feeding level of TDN (Total Digestible Nutrients) on the generation of main greenhouse gases such as carbon dioxide and methane in Hanwoo cows. The diet TDN (kg) adjusted to achieve ADG of 0 g/day (Control), 200 g/day (T1), and 400 g/day (T2) of the maintenance level TMR (Total Mixed Ration) delivered twice a day at 08:30 and 17:30. Cow are housed in a respiration chamber and the environmental temperature was maintained at $20^{\circ}C$. The gases were measured for 24 hours using the multi-detector instrument Mamos-300. The analyzed methane emissions of T1 and T2 were 33.5% and 69.6% higher than control, respectively, and the carbon dioxide emissions were 21.1% and 40.6% higher than control. Also, the hourly pattern of carbon dioxide and methane production were showed very similar emission. Gas production showed peak after 1 hour of feeding and this gap was wider in the afternoon than in the morning hours. It is clearly conducted that $CO_2$ and $CH_4$ emissions were different by limited intake levels of feed.

• Journal of Fashion Business
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• v.9 no.4
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• pp.59-78
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• 2005

This study aims to know the deferences of hair fashion feeling group in accordance with hair styling activities, general characteristics, life styles objecting to capital area university women students and aid to hair fashion design. So the results are as belows. 1. Frequency Analysis of Categories A. Hair fashion feeling - Natural, sexy, romantic pretty, sophisticate, ethnic are 90% in total hair fashion feeling variables in sequence of frequency, so it can be said these are in vogue. B. Hair styling activities - The objections visit the hair salon once 1-2months, spend about 42,000 won a month, perform cut & wave perm to sentimental reasens & hair style changes, determine the hair style well coordinated in her image and managed easily. In her home, they manage her hair style 12 minutes a day, spend 17,000 won to buy hair aids, do hair blow dry or pin or pony tail mainly in the morning, scarcely use the hair styling aids but if use, essence or wax mainly. And the degree of interest to hair style is high. C. General Characteristics - The objections's average age is 21.1, residence is seoul kangnam 23.3%, seoul kangbook 18.4%, other capital areas 58.4%, the degree of education is university students 94.9%, graduated student 5.1%, marriage is married 96%, unmarried 2.8%, family who live with is married are mainly man & woman and living with father & mother in low in man's, unmarried are mainly live alone & nuclear family, personal expenses a month is 300,000 won in average, income of home is 4,000,000 won a month. D. Life style - The objections are not in interest of physical exercises but if are, do yoga & health, like drama & comedies program, watch TV or meet friend in leisure time, like balad & dance music, fashion magazine, meet friend in cafe or college. 2. Relationship of hair fashion feeling & other variables Using the $x^2$-test, level p<0.05, Hair styling activities(frequency of hair salon coming in and out, ordinary time representing hair style, preferred hair styling aids, the amount of hair style interest), General Characteristics(age), Life style(leisure time) variables are meaningful.

• Journal of Korean Society for Geospatial Information Science
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• v.23 no.1
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• pp.65-71
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• 2015

Red Tide phenomenon which happens in the southern coast of Korea gives massive damage to the fishermen who run fish farms and thereby a lot of efforts to prevent damage are made from various angles. In particular, red tide monitoring with satellite imagery can make it possible to obtain the occurrence data of red tide throughout the whole areas of the sea, which helps provide important information for establishing the preventive plans of disasters. In this regard, this study selected the South Sea of Gyeongnam Province with a view to suggesting the monitoring results with regard to the spread and reduction of the Red Tide in the middle of the day by using the GOCI Images of COMS. With this intention, it selected the region in the South Sea of Gyeongnam Province. The study results of analysis on the GOCI image data for the years of 2013(Aug. 12) and 2014 (Sep. 11) are as follows: the pattern of the Red Tide in the region of the South Sea occurred in the southern sea area of Geoje-do in the morning. It gradually spread and showed a gradual decline after reaching the top at 1 PM. In addition, in terms of the tide movement in the middle of the day, Red Tide began in the southern sea area and moved to the west, and moved to the east again at noon. It is judged that additional study on many factors such as the characteristics of the future Red-tide organisms, tidal currents, amount of sunshine, and water temperature is needed, but it is estimated that Red Tide movement monitoring with GOCI images would provide very crucial information for predicting the spread and movement of the Red Tide to protect and manage the Red Tide disasters.

• Journal of the Korean Society of Food Culture
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• v.20 no.5
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• pp.594-602
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• 2005

The purpose of this study was to investigate eating behaviors related to snack and self-purchasing snack (SPS) among elementary school children. Self-administered questionnairs were completed by 352, 5th and 6th grade elementary school students living in 3 different regions which included apartment region in Bundangn, Sungnam (apartment group, n=116), residences in Seodaemun-Gu and Mapo-Gu, Seoul (kang-buk group, n=103) and residence in industrial region in Sungnam (industry group, n=133). The results were as follows: A significantly higher proportion (64.7%) of the apartment group had breakfast every morning than those of kang-buk (48.6%) or industry (52.1%) group (p<0.01). As for the frequency rate of snack and self-purchasing snack (SPS), 53.9% of the subjects answered taking snack more than once per day, 22.8%, once for few days and 23.3%, almost not. However, 15.5% of the subject had SPS once or more per day, 30.7%, 1-2 times per week and 22.4%, almost not. Those of apartment group showed significantly lower SPS frequencies (p<0.01), since higher proportions answered having SPS 1-2times per week (40.9%) and almost not (31.3%) compared to other groups. The reasons for having SPS turned out to be 'hunger' 54.7%, 'being habitual', 15.9%, 'bing bored', 15.7% and 'with peers' 13.7%. When subjects selected SPS foods, they considered taste (31.5%), price (23.0%), mood at the time (14.1%), sanitorial aspect (10.2%) and quantity (10.1%) rather than nutritional aspect (7.2%). Subjects' pocket money was estimated as 3736 won per week and SPS expense per time as 706 won. But subjects who spent more than 2000 won for SPS expense were significantly higher (33.0%) in apartment group than those of other groups (p<0.01). The favorite snack items that subjects having at home were fruit, ice cream, milk and yoghurt, cookies, ramen and bread in order. And favorite SPS items turned out to be ice cream, cookies, duckbokki, frozen bars, gum, chocholate and candy in order. The frequency rate of SPS were evaluated to be significantly related by several variables: those living in apartment area (p<0.01), those taking breakfast regularly (p<0.01), those of normal weight status by Rohrer index (p<0.05) and those receiving less pocket money (p<0.01) showed lower SPS frequency rate.