• Journal of Digital Contents Society
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• v.8 no.1
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• pp.77-83
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• 2007

The handoff area is the region where a call can be handled by the base station in any of the adjacent cells, and duration time is viewed as the time a mobile station resides in the handoff area. In this paper, probability distribution about hand off time one of important parameter at traffic modelling in mobile communication system was estimated. First, point statistic is applied using sample data obtained from simulation result to choose the group of distribution of handoff duration time. Second, parameters are estimated to decide specific distribution function. For this, the value of parameters is calculated using MLE(Maximum Likelihood Estimate.) and goodness of fit test is performed. finally these results show that handoff duration time follows gamma distribution.

• Journal of Physiology & Pathology in Korean Medicine
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• v.36 no.1
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• pp.7-10
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• 2022

Hwangryunagyo-tang (HT) is a herbal cocktail to treat insomnia induced by yin deficiency with effulgent fire. In the present study, the onset time and the duration time of sleep were measured 30 minutes after thiopental sodium injection. And c-fos immunohistochemistry was performed to find the activated nerve cells of the ventrolateral preoptic nucleus (VLPO) and tuberomammillary nucleus (TMN) sites in the brain. HT significantly increased the number of activated nerve cells in the sleep-inducing center (VLPO), whereas HT significantly decreased the number of activated nerve cells in the arousal center (TMN). It could be concluded that the HT shortened the onset time and increased the duration time for sleep induced by thiopental sodium. And it was confirmed that the mechanism acted by activating the sleep-inducing center (VLPO) and suppressing the arousal center (TMN) in the brain. The results are considered to be useful as scientific evidence HT can be used clinically for the treatment of insomnia caused by yin deficiency with effulgent fire.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.5
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• pp.675-690
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• 2019

Objective: This study investigated the effect of diet and roughage quality (RQ) on dry matter intake, duration and number of daytime and night-time eating bouts, idling sessions and ruminating activities in small ruminants. Methods: In Exp 1 and 2, RQ was improved by urea treatment of veld hay, while diet quality was improved by supplementing with Lucerne hay (Exp 3), sunflower meal and lespedeza (Exp 4), fish meal (Exp 5a), and sunflower meal (Exp 5b). In all experiments goats and sheep were blocked by weight and randomly allocated to experimental diets. Day-time (06:00 to 18:00 h) and night time (18:00 to 06:00 h) feeding behaviour activities were recorded. Results: RQ affected rumination index in Exp 1, but not in Exp 2, 3, and 5. Time spent eating and ruminating was affected by RQ (Exp 1, 3, and 4), period of day (all experiments) and their interaction (Exp 1). Intake rates (g/bout and g/min) were similar across diets. Period of day affected the duration of rumination sessions (Exp 1, 2, and 3); diet or RQ affected the duration of eating bouts (Exp 3) and rumination sessions (Exp 1 and 2). RQ had a significant effect on the duration of eating sessions in Exp 3 only, whilst period of day affected this same behaviour in Exp 2 and 3. Generally, goats and sheep fed on roughage alone ruminate at night and eat more during the day but those fed a roughage and supplemented with Lucerne hay spent more time ruminating than eating. Time spent eating and ruminating had positive correlations to crude protein and feed intake. Intake rates had strong positive correlations to intake. Conclusion: Chewing time, number of eating and ruminating sessions, and duration of eating bouts are physiologically controlled in small ruminants, though chewing time requires isometric scaling during modelling of intake.

• Journal of The Korean Society of Agricultural Engineers
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• v.65 no.4
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• pp.25-32
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• 2023

KDS (Korean Design Standard) for agricultural drainage is a planning standard that helps determine the appropriate capacity and type of drainage facilities. The objective of this study was to analyze the inundation of the agricultural basin considering the current design standard and the critical rainfall duration. This study used the rainfall durations of 1-48 hour, and the time distribution method with the Chicago and the modified Huff model. For the runoff model, the NRCS (Natural Resources Conservation Service) unit hydrograph method was applied, and the inundation depth and duration were analyzed using area-elevation data. From the inundation analysis using the modified Huff method with different rainfall durations, 4 hours showed the largest peak discharge, and 11 hours showed the largest inundation depth. From the comparison analysis with the current method (Chicago method with a duration of 48 hours) and the modified Huff method applying critical rainfall duration, the current method showed less peak discharge and lower inundation depth compared to the modified Huff method. From the simulation of changing values of drainage rate, the duration of 11 hours showed larger inundation depth and duration compared to the duration of 4 hours. Accordingly, the modified Huff method with the critical rainfall duration would likely be a safer design than the current method. Also, a process of choosing a design hydrograph considering the inundation depth and duration is needed to apply the critical rainfall duration. This study is expected to be helpful for the theoretical basis of the agricultural drainage design standards.

• Phonetics and Speech Sciences
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• v.9 no.2
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• pp.85-94
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• 2017

Conventional speaker verification systems using time delay neural network, identity vector and probabilistic linear discriminant analysis (TDNN-Ivector-PLDA) are known to be very effective for verifying long-duration speech utterances. However, when test utterances are of short duration, duration mismatch between enrollment and test utterances significantly degrades the performance of TDNN-Ivector-PLDA systems. To compensate for the I-vector mismatch between long and short utterances, this paper proposes to use probabilistic linear discriminant analysis (PLDA) model adaptation with augmented data. A PLDA model is trained on vast amount of speech data, most of which have long duration. Then, the PLDA model is adapted with the I-vectors obtained from short-utterance data which are augmented by using vocal tract length perturbation (VTLP). In computer experiments using the NIST SRE 2008 database, the proposed method is shown to achieve significantly better performance than the conventional TDNN-Ivector-PLDA systems when there exists duration mismatch between enrollment and test utterances.

• Journal of the military operations research society of Korea
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• v.29 no.2
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• pp.1-12
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• 2003

Knowing the characteristic of battle duration is important for commanders and logicians in the analysis of combat realization. Analytic solutions for mean and standard deviation can be found in small sized battles. Stochastic combat simulation model is utilized to study a probabilistic behavior of the combat duration. Output data is fitted to a certain probability distribution and some moments such as skewness and kurtosis are investigated. Fire allocation strategies, reselect options, interfiring time random variables, and kill rates are considered to investigate how they affect the battle termination time.

• Journal of Korean Public Health Nursing
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• v.28 no.2
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• pp.241-257
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• 2014

Purpose: The purpose of this study was to investigate the combined influence of screen based sedentary behavior and sleep duration on obesity, depression, and suicidal ideation in Korean Adolescents. Methods: This cross sectional study used secondary data from the 2013 Adolescent Health Behavior Online Survey. A total of 27,929 high school students were included in the study. Logistic regression was used for analysis of the combined influence of screen based sedentary behavior and sleep duration on obesity, depression, and suicidal ideation. Results: Obesity was more prevalent among adolescents who had ${\geq}$ 4h of screen based sedentary behavior and <7h of sleep duration compared to the reference group, defined as < 2h of screen time and > 7h of sleep duration. Depression and suicidal ideation were more prevalent among adolescents who had 2-4h of screen based sedentary behavior and <7h of sleep duration compared to the reference group. Conclusion: Based on the results of this study, maintaining a low (< 2h) level of screen based sedentary behavior and appropriate sleep duration over 7 hours per day is essential for prevention of adolescent obesity, depression, and suicidal ideation.

• Journal of Preventive Medicine and Public Health
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• v.56 no.1
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• pp.59-66
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• 2023

Objectives: The aim of this study was to evaluate the effect of body weight status and sleep duration on the discrete-time hazard of menarche in Korean schoolgirls using multiple-point prospective panel data. Methods: The study included 914 girls in the 2010 Korean Children and Youth Panel Study who were in the elementary first-grader panel from 2010 until 2016. We used a Gompertz regression model to estimate the effects of weight status based on age-specific and sex-specific body mass index (BMI) percentile and sleep duration on an early schoolchild's conditional probability of menarche during a given time interval using general health condition and annual household income as covariates. Results: Gompertz regression of time to menarche data collected from the Korean Children and Youth Panel Study 2010 suggested that being overweight or sleeping less than the recommended duration was related to an increased hazard of menarche compared to being average weight and sleeping 9 hours to 11 hours, by 1.63 times and 1.38 times, respectively, while other covariates were fixed. In contrast, being underweight was associated with a 66% lower discrete-time hazard of menarche. Conclusions: Weight status based on BMI percentiles and sleep duration in the early school years affect the hazard of menarche.

• Agribusiness and Information Management
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• v.7 no.2
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• pp.1-11
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• 2015

This study has performed a comparative analysis between groups based on Time To First Fixation, Fixation Duration, Fixation Count and Total Visit Duration, which are eye-tracking analysis indicators on what visual attention is shown compared to the e-magazine produced as regular images related to e-magazines in which experiment subjects have applied cinemagraph images as eye tracking research on the e-magazine produced with cinemagraph images and e-magazines produced with regular images. The experiment sample used e-magazines composed of nine pages while AOI (area of interest) has been set up on each page by classifying image and text regions. A combined 30 people took part in the experiment, which was performed by randomly assigning 15 to the experiment group and 15 to the control group. According to the results of the analysis, the experiment group recorded a shorter time than the control group on the e-magazine produced with cinemagraph images through Time To First Fixation. Though no significant difference was found between the experiment and control groups in Fixation Duration, a substantial difference did appear between Fixation Duration and Total Visit Duration.

• Journal of Communications and Networks
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• v.5 no.1
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• pp.25-32
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• 2003

4G mobile communication system requires the throughput of 10-100Mbps. Adaptive modulated OFDM system is promising technique for increasing the throughput. In the pilot symbol assisted high-speed packet transmission system, the data symbol duration is generally considered to be small compared to the coherence time. However, OFDM symbol duration is longer than the symbol duration of a single carrier system, so that the packet duration of the pilot symbol assisted high speed packet transmission system is long. In this case, the change of channel conditions is too fast to be accurately estimated by channel estimator at the receiver in high Doppler frequency, so that many errors occur during demodulation, especially with the data symbols at the end of each packet. In this paper, we consider the BER at various instantaneous $E_b/N_o$ that includes the demodulation errors in high Doppler frequency. When the coherence time is ten times longer than the duration of a single packet, the channel can be closely approximated as an AWGN channel. Otherwise, the approximation breaks down and the above-mentioned errors that occur during demodulation must be taken into consideration. In this paper, we propose the pilot symbol assisted high speed packet transmission system based on adaptive OFDM using a novel lookup table to consider the demodulated errors and evaluate the throughput performance.