• Journal of Satellite, Information and Communications
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• v.4 no.2
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• pp.34-38
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• 2009

This paper is related with optimum burst structure design for high efficient TDMA satellite return link transmission. In general, some typical burst structure for data transmission is composed of a pair of preamble and traffic data in the DVB-RCS (Digital Video Broadcasting. Return Channel via Satellite) and IPOS (IP over Satellite) standard. This structure has some difficulties to increase spectral efficiency that it requires a large of preamble length, high SNR environment, or receiver complexity. To cope with them, burst structure with distributed pilot symbol can be used to alleviate the residual frequency offset effect by calculating accurate frequency offset than conventional one. In particular, we investigate some relevant to proposed distributed pilot structure, previously and analyze their strong points/drawbacks in terms of synchronization to draw the most appropriate one.

• Journal of KIISE:Databases
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• v.35 no.3
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• pp.199-207
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• 2008

The FP-tree(Frequency Pattern Tree) mining association rules algorithm was proposed to improve mining performance by reducing DB scan overhead dramatically, and it is recognized that the performance of it is better than that of any other algorithms based on different approaches. But the FP-tree algorithm needs a few more memory because it has to store all transactions including frequent itemsets of the DB. This paper implements a FP-tree algorithm on a general purpose UNK system and compares it with the DHP(Direct Hashing and Pruning) algorithm which uses hash tree and direct hash table from the point of memory usage and execution time. The results show surprisingly that the FP-tree algorithm is poor than the DHP algorithm in some cases even if the system memory is sufficient for the FP-tree. The characteristics of the test data are as follows. The site of DB is look, the number of total items is $1K{\sim}7K$, avenrage length of transactions is $5{\sim}10$, avergage size of maximal frequent itemsets is $2{\sim}12$(these are typical attributes of data for large-scale convenience stores).

• Journal of Korean Society of Transportation
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• v.27 no.4
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• pp.207-215
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• 2009

Generally, traffic accidents can be influenced by variables driving conditions including geometric, roadside design, and traffic conditions. Under the circumstance, homogeneous roadway segments were firstly identified using typical geometric variables obtained from field data collections in this study. These field data collections were conducted at highways located in several areas having various regional conditions for examples, outside metropolitan city; level and rolling rural areas. Due to many zero cells in crash database, a Zero Inflated Poisson model was used to develop crash prediction model to overestimated results in this study. It was found that EXPO, radius, grade, guardrail, mountainous terrain, crosswalk and bus-stop have statistically significant influence on vehicle to vehicle crashes at rural multi-lane roadway segments.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.19 no.2
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• pp.104-109
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• 2016

Purpose: Regurgitation is a common physiological phenomenon in infants. The aim of the present study was to evaluate the efficacy of a new anti-regurgitation (AR) formula (Novalac), thickened with an innovative complex including fibres, on the daily number of regurgitations and to assess its impact on stool consistency and frequency. Methods: Infants younger than five months, presenting at least 5 regurgitations per day were recruited in this trial. The efficacy of the new formula on regurgitation (daily number and Vandenplas score), stool frequency and consistency were assessed at day 14 and 90. Growth data were recorded at each study visit. Results: Ninety babies (mean age $9.6{\pm}5.8weeks$) were included in the full analysis data set. The mean number of regurgitation episodes at inclusion was $7.3{\pm}3.4$. In all infants, regurgitations improved after 2 weeks. The daily number of regurgitations decreased significantly ($-6.3{\pm}3.3$, p<0.001) including in those previously fed a thickened formula ($-6.2{\pm}3.0$, p<0.001). There was no significant change in stool consistency at day 14. After 3 months, 97.5% of infants had formed or soft stools. Growth was appropriate with a slight increase of weight-for-age z-score (from $-0.5{\pm}1.0$ to $-0.1{\pm}0.9$) and no change of weight-for length z-score ($-0.1{\pm}1.1$ to $-0.1{\pm}-1.1$). Conclusion: The new AR formula thickened with an innovative complex is very effective in reducing the daily number of regurgitations without having a negative impact on stools consistency.

• Journal of the Korean Home Economics Association
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• v.43 no.5 s.207
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• pp.199-219
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• 2005

The purpose of this study was to investigate the prevalence and to identify the related factors of overweight among young children. The study subjects were 138 children, aged 3-5, attending child care centers in the Kyungbuk area. We assessed a wide range of collected variables including general characteristics, anthropometric data, dietary habits, stress, food preferences, and food frequencies of young children, and anthropometric data and general characteristics of their parents. The results of this study were analyzed with $\chi$$^{2}$_ or t-test using SPSS package program. The subjects were classified into two groups using the weight for length index WLI criteria: normal group(n=101) and overweight group(n=37). Forty-nine percent of mothers of overweight children did not recognize their child's current overweight status. Scores for encountering criticized-violent situation stress, hurt-pride stress and total stress were higher in the overweight group than in the normal group. The frequency of snacking and the appetite of the overweight group were increased compared to those of the normal group. The overweight group had higher preferences for salad, kimbab, boiled rice with meat, vegetables and Chinese noodles, chicken, shell, banana, soybean milk, hotdog, and potato than the normal group. The overweight group showed higher consumption frequencies of pan-fried foods, egg, laver and strawbery compared to the normal group. Therefore, our results suggest that obese young children, as well as their parents, need more nutritional counseling education about dietary habits, food preference, recognition of normal weight and strategies for actively coping with stresstopreventandtreatobesityandtomaintainhealth. .

• Bulletin of the Society of Naval Architects of Korea
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• v.17 no.1
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• pp.25-29
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• 1980

For the preliminary estimation of the vertical hull natural frequency, the Schlick's or Schlick-type formulae have been traditional ones and are still in common use today. Some investigators have made their efforts, based on statistical data of ships' system parameters, to extend the applicability of Schlick-type formulae to higher modes, or to utilize the Rayleigh method. For instance, the work done by Dinsenbacher et al.[5] belongs to the former and that of Nagamoto et al.[6] to the latter. In a part of his previous paper[7], the author, investigating the case of a cargo ship of medium size, suggested that provided statistically simplified curves such as trapezoid of system parameter distributions are available in hands, direct utlization of an ordinary computer program can be also an another convenient method by which we can obtain both natural frequencies and normal mode shapes. In this paper, to confirm the feasibility of the above suggestion, four high speed boats are investigated. The system parameters of them are originally given in [5]. The computer program used here is one confiled based on a calculation method derived from Myklestal-Prohl modeling of hull, transfer matrix formulation and an extended Gumbel's initial value method for solving frequency equation. The results of the investigation show that the direct calculation based on statistically oriented and reasonably assumed trapezoidal mean curves of system parameter distributions can give us natural frequencies within about 5% deviation up to several-noded modes and normal mode shapes serviceable at least up to 4- or 5-noded modes in comparision with those based on actual distributions of system parameters. For this simplified method the actual data required for input are only of ship length, displacement, total added mass, bending and shear rigidity at amidship. They are available at the early stage of design. By this method we can also easily trace variations of vibration characteristics in the course of ship design cycles.

• Korean Journal of Community Nutrition
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• v.22 no.1
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• pp.40-52
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• 2017

Objectives: This study was conducted to examine the length of exposure to smartphone and its association with dietary behavior toward snacks, lifestyle, and nutrition knowledge in elementary school students. Methods: Subjects were 372 5th and 6th grade schoolchildren in Cheongju, Korea, and data was collected by a self-administered questionnaire. They were divided into two groups by the time spent using smartphone: moderate (< 2 hours/day) and overexposure (${\geq}2$ hours/day). Data was analyzed using frequency analysis, ${\chi}^2$-test, and independent t-test as well as analysis of covariance when necessary. Results: Approximately half of subjects (41.4%) reported spending ${\geq}2$ hours/day using smartphone. That habit was more frequent among students in the 6th grade, those who received more monthly allowance, and who has a working mother. 63.4% of the subjects reported that they consumed snacks while watching television, using a computer and/or a smartphone and 48.1% said that they consumed snacks while they use a smartphone. Both situations were most prevalent among those with overexposure to smartphone (${\geq}2$ hours/day). We also observed that a higher percentage of subjects from the overexposure group spent more money on snack foods with the preference for ice cream, fast food, and carbonated drinks. Further, those in the overexposure group consumed more ice cream, cookies, and carbonated drinks. In addition, they had less desirable dietary behavior and health-related lifestyle (sleep duration and frequency of regular exercise) compared to those with moderate smartphone usage (< 2 hours/day). However, there was no statistical difference in nutrition knowledge among children with different degrees of smartphone usage. Conclusions: Our results showed that longer smartphone use was associated with less desirable snack preference/consumption and other dietary behavior in elementary school students. Thus interest and positive attitudes towards healthy snacks and diet should be reinforced in nutrition education programs, especially for those who are prone to use smartphones.

• Animal Bioscience
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• v.34 no.12
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• pp.1895-1902
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• 2021

Objective: Runs of homozygosity (ROH) are contiguous lengths of homozygous genotypes that can reveal inbreeding levels, selection pressure, and mating schemes. In this study, ROHs were evaluated in Wannan Black pigs to assess the inbreeding levels and the genome regions with high ROH frequency. Methods: In a previous study, we obtained 501.52 GB of raw data from resequencing (10×) of the genome and identified 21,316,754 single-nucleotide variants in 20 Wannan Black pig samples. We investigated the number, length, and frequency of ROH using resequencing data to characterize the homozygosity in Wannan Black pigs and identified genomic regions with high ROH frequencies. Results: In this work, 1,813 ROHs (837 ROHs in 100 to 500 kb, 449 ROHs in 500 to 1,000 kb, 527 ROHs in >1,000 kb) were identified in all samples, and the average genomic inbreeding coefficient (F_ROH) in Wannan Black pigs was 0.5234. Sixty-one regions on chromosomes 2, 3, 7, 8, 13, 15, and 16 harbored ROH islands. In total, 105 genes were identified in 42 ROH islands, among which some genes were related to production traits. Conclusion: This is the first study to identify ROH across the genome of Wannan Black pigs, the Chinese native breed of the Anhui province. Overall, Wannan Black pigs have high levels of inbreeding due to the influence of ancient and recent inbreeding due to the genome. These findings are a reliable resource for future studies and contribute to save and use the germplasm resources of Wannan Black pigs.

• Structural Engineering and Mechanics
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• v.81 no.5
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• pp.565-574
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• 2022

The infrastructures such as offshore, bridges, power plant, oil and gas piping and aircraft operate in a harsh environment during their service life. Structural integrity of engineering components used in these industries is paramount for the reliability and economics of operation. Two regression models based on the concept of Gaussian process regression (GPR) and Minimax probability machine regression (MPMR) were developed to predict stress intensity factor range (𝚫K). Both GPR and MPMR are in the frame work of probability distribution. Models were developed by using the fatigue crack growth data in MATLAB by appropriately modifying the tools. Fatigue crack growth experiments were carried out on Eccentrically-loaded Single Edge notch Tension (ESE(T)) specimens made of API 5L X65 Grade steel in inert and corrosive environments (2.0% and 3.5% NaCl). The experiments were carried out under constant amplitude cyclic loading with a stress ratio of 0.1 and 5.0 Hz frequency (inert environment), 0.5 Hz frequency (corrosive environment). Crack growth rate (da/dN) and stress intensity factor range (𝚫K) values were evaluated at incremental values of loading cycle and crack length. About 70 to 75% of the data has been used for training and the remaining for validation of the models. It is observed that the predicted SIF range is in good agreement with the corresponding experimental observations. Further, the performance of the models was assessed with several statistical parameters, namely, Root Mean Square Error (RMSE), Mean Absolute Error (MAE), Coefficient of Efficiency (E), Root Mean Square Error to Observation's Standard Deviation Ratio (RSR), Normalized Mean Bias Error (NMBE), Performance Index (ρ) and Variance Account Factor (VAF).

• Health Policy and Management
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• v.33 no.3
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• pp.264-272
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• 2023

Background: Private health insurance supplements the coverage of national health insurance in Korea. In this situation, the subject of the study is to identify the healthcare utilization of people with physical and mental illnesses according to private health insurance. Methods: This study used data from the Korea Health Panel Survey 2018. The study population consisted of 813 individuals with physical and mental illnesses (PMI). Multiple logistic regression analysis and binominal logistic regression analysis were conducted about the utilization of emergency, inpatient, and outpatient medical services of people with PMI depending on enrollment in private health insurance (PHI). Results: The results of this study indicated that individuals with PHI utilized emergency and outpatient medical services less frequently compared to those without PHI. Conversely, having PHI was associated with a higher utilization of inpatient medical services compared to not having PHI. Binomial logistic regression analysis revealed that individuals with PMI who had PHI exhibited a higher frequency of visits to emergency and outpatient medical services compared to those without PHI. However, the significance of this trend was not observed in the case of emergency medical services. On the other hand, individuals with PMI who had PHI showed a lower frequency of visits to inpatient medical services compared to those without PHI. Conclusion: In conclusion, there was a significant relationship between having PHI and the utilization of medical services in people with PMI. There is a need for a follow-up study considering the type of mental illnesses, length of stay, and health outcome of people with PMI depending on having PHI.