• Structural Engineering and Mechanics
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• v.85 no.1
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• pp.1-14
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• 2023

The use of functionally graded materials in applications involving severe thermal gradients is quickly gaining acceptance in the composite mechanics community, the aerospace and aircraft industry. In the present study, a refined sandwich plate model is applied to study the free vibration analysis of porous functionally graded material (FGM) sandwich plates with various distribution rate of porosity. Two types of common FG sandwich plates are considered. The first sandwich plate is composed of two FG material (FGM) face sheets and a homogeneous ceramic or metal core. The second one consists of two homogeneous fully metal and ceramic face sheets at the top and bottom, respectively, and a FGM core. The displacement field of the present theory is chosen based on nonlinear variations in the in-plane displacements through the thickness of the sandwich plate. The number of unknowns and equations of motion of the present theory is reduced and hence makes them simple to use. In the analysis, the equation of motion for simply supported sandwich plates is obtained using Hamilton's principle. In order to present the effect of the variation of the porosity distribution on the dynamic behavior of the FGM sandwich plates, new mixtures are proposed which take into account different rate of porosity distribution between the ceramic and the metal. The present method is applicable to study the dynamic behavior of FGM plates and sandwich plates. The frequencies of two kinds of FGM sandwich structures are analyzed and discussed. Several numerical results have been compared with the ones available in the literature.

• Journal of agricultural medicine and community health
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• v.19 no.1
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• pp.41-52
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• 1994

The aim of this study was to assess the people's need for visiting health services in a rural area. In recent years, the great concern for the visiting health services has aroused in Korea. Stratified cluster sample for a household survey was used to select 1,255(8.4%) Households from Yonchon county. This study was undertaken from July 26 to August 7 in 1993. Medically defined need, usually expressed by the prevalencies or rates of specific disease, was evaluated with the use of criteria established by medical and nursing professors and expressed by the percent of specific objects for the visiting health services. Perceived need represented by the acceptability for the visiting services and willingness to paying for it, also, evaluated. The major results were as follows : 1. Of the 348 patients with hypertension, 201 were the non-compliant patients, the rate of the non-compliant hypertension patients in 4,577 study population was 7.4%. 2. Of the 141 diabetic patients, 73 were the non-compliant patients, the rate of the non-compliant hypertension patients in 4,577 sample population was 2.7%. 3. The number of patients with severe musculo-skeletal disease was 24, the rate was 0.9% above the age 30. 4. Of the 514 elderly, 33 were the elderly without any family member, the rate was 8.4%. Those with severely decreased activity of daily living were 13. 5. Infants with high risks were 12, pregnant women and neonates were 5, patients discharged within 1 week and with special equipments such as peritoneal dialysis, stoma, TPN etc. were 17, and patients with cancer were 5. Total number of the objects needed visiting health services was 752(18.43%) of the 4,577 study population. Perceived need evaluated were as follows; The acceptance rate of visiting health services was 74.9%, The kinds of visiting health services such as family health protection and promotion, early detection of hypertension, physiotherapy, health education and counseling were needed in the order of high rate The price willing to pay for visiting health services per visit was about 3,000-5,000Won. In conclusion, Visiting health services programme to be developed should have priority to the prevention of complications of chronic disease such as hypertension, diabetes milletus, elderly disease and health promotion.

• Korean Journal of Veterinary Research
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• v.37 no.4
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• pp.899-909
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• 1997

The aim of this study was to assess the estimates of the time of ovulation and mating derived by plasma progesterone concentration. The 40 mature Korea Jin-do bitches were monitored to determine the plasma progesterone concentrations from proestrus to parturition. Gestation length in the 30 pregnant bitches was $63.9{\pm}2.3$ ($mean{\pm}SD$) days in multiparous bitches and $61.8{\pm}3.6$ days in primiparous bitches when Day 0 was timed from the first day of male acceptance, and $61.4{\pm}1.8$ days and $61.3{\pm}2.7$ days when Day 0 was timed from the day of first mating, respectively. Also, gestation length was $63.1{\pm}1.4$ days, $62.4{\pm}1.1$ days and $61.5{\pm}0.9$ days in multiparous bitches, and $62.6{\pm}1.4$ days, $62.4{\pm}2.0$ days and $61.6{\pm}2.3$ days in primiparous bitches when Day 0 was timed from the day that plasma progesterone concentration was first increased above 2.0, 3.0 and 4.0ng/ml, respectively, and $53.8{\pm}3.1$ days and $54.8{\pm}2.6$ days when Day 0 was timed from the last day of male acceptance, respectively. In 30 pregnant bitches, plasma progesterone concentration was $0.2{\pm}0.2ng/ml$ in multiparous bitches and $0.7{\pm}0.8ng/ml$ in primiparous bitches at the first day of vulval bleeding, $1.9{\pm}1.0$ and $3.3{\pm}2.7ng/ml$ at the first day of male acceptance, $7.0{\pm}4.0$ and $9.3{\pm}6.2ng/ml$ at the day of first mating, and $25.1{\pm}6.3$ and $22.8{\pm}10.3ng/ml$ at the last day of male acceptance, respectively. When Day 0 was timed from the day of parturition, plasma progesterone concentration at Day -62, Day -63 and Day -64 was $4.7{\pm}2.7ng/ml$, $3.5{\pm}2.2ng/ml$ and $1.7{\pm}0.9ng/ml$ in multiparous bitches, and $5.3{\pm}4.4ng/ml$, $3.2{\pm}3.7ng/ml$ and $2.0{\pm}1.9ng/ml$ in primiparous bitches, respectively. When Day 0 was timed from the day that plasma progesterone concentration was first increased above 3.0ng/ml after the first day of vulval bleeding, plasma progesterone concentration at Day 61 and Day 62 was $2.7{\pm}2.2ng/ml$ and $1.4{\pm}1.9ng/ml$ in multiparous bitches, and $3.4{\pm}5.2ng/ml$ and $3.7{\pm}5.6ng/ml$ in primiparous bitches, and $0.8{\pm}0.7ng/ml$ and $0.9{\pm}0.4ng/ml$ at Day 63, respectively. It was that bitches were mated when plasma progesterone concentraion was 1.9 to 14.2ng/ml and 3.5 to 20.0ng/ml in multiparous and primiparous bitches, which was between first day before ovulation and fourth day after ovulation. And pregnancy rate was 92% (23/25). From these data, ovulation was estimated to occur the day when plasma progesterone concentration was first increased above 3.0ng/ml after the first day of vulval bleeding. It was estimated that mating time was the day when plasma progesterone concentration was between 1.9 and 20.0ng/ml, and best time for mating was between 3.0 and 8.0ng/ml of plasma progesterone concentration.

• Progress in Medical Physics
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• v.22 no.2
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• pp.61-66
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• 2011

In this study, we evaluated the effect of grid size on dose calculation accuracy using 2 head & neck and 2 prostate IMRT cases and based on this study's findings, we also evaluated the efficiency of a 2D diode array detector for IMRT quality assurance. Dose distributions of four IMRT plan data were calculated at four calculation grid sizes (1.25, 2.5, 5, and 10 mm) and the calculated dose distributions were compared with measured dose distributions using 2D diode array detector. Although there was no obvious difference in pass rate of gamma analysis with 3 mm/3% acceptance criteria for the others except 10 mm grid size, we found that the pass rates of 2.5, 5 and 10 mm grid size were decreased 5%, 20% and 31.53% respectively according to the application of the fine acceptance criteria, 3 mm/3%, 2 mm/2% and 1 mm/1%. The calculation time were about 11.5 min, 4.77 min, 2.95 min, and 11.5 min at 1.25, 2.5, 5, and 10 mm, respectively and as the grid size increased to double, the calculation time decreased about one-half. The grid size effect was observed more clearly in the high gradient area than the low gradient area. In conclusion, 2.5 mm grid size is considered acceptable for most IMRT plans but at least in the high gradient area, 1.25 mm grid size is required to accurately predict the dose distribution. These results are exactly same as the precious studies' results and theory. So we confirmed that 2D array diode detector was suitable for the IMRT QA.

• Proceedings of the KSME Conference
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• 2007.05b
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• pp.1953-1958
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• 2007

This paper presents the results of a series of performance tests for the integral Stirling cryocooler. Infrared sensor systems incorporating cryocoolers are required to be qualified to the appropriate environmental specification. Integral Stirling cryocooler for thermal imaging system have matured to the stage of undergoing formal qualification test program. The thermal environmental test of the Stirling cryocooler is presented in this paper. We performed that low and high temperature keeping test from $-40^{\circ}C$ to $+71^{\circ}C$ and operating test at high and low temperature cyclic range with acceptance tests performed at scheduled intervals. Cooldown time to 80K and steady state input power at 80K were determined as a function of cooler components temperatures at the compressor, hot end and cold tip. Tests performed on this cooler have been successful with a measured cooldown time to 80K of less than 5 minutes 24seconds for $71^{\circ}C$ ambient temperature with input power of 11W

• ETRI Journal
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• v.34 no.6
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• pp.807-815
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• 2012

In this paper, we propose a scheme for partially dynamic lane control for energy saving in multilane-based high-speed Ethernet. In this scheme, among the given transmission lanes, at least one lane is always operating, and the remaining lanes are dynamically activated to alleviate the network performance in terms of queuing delay and packet loss in the range of acceptance. The number of active lanes is determined by the decision algorithm based on the information regarding traffic and queue status. The reconciliation sublayer adjusts the transmission lane with the updated number of lanes received from the algorithm, which guarantees no processing delay in the media access control layer, no overhead, and minimal delay of the exchanging control frames. The proposed scheme is simulated in terms of queuing delay, packet loss rate, lane changes, and energy saving using an OPNET simulator. Our results indicate that energy savings of around 55% (or, when the offered load is less than 0.25, a significant additional savings of up to 75%) can be obtained with a queuing delay of less than 1 ms, a packet loss of less than $10^{-4}$, and a control packet exchange time of less than $0.5{\mu}s$ in random traffic.

• The Korean Journal of Health Service Management
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• v.6 no.3
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• pp.1-11
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• 2012

The purpose of this study is to identify the effects of emergency medical technicians' personal traits and job characteristics on job/social stress, job satisfaction, role conflicts, organizational commitment, and self-efficacy. The study population was emergency medical technicians who is working at the hospitals in Yeungnam province. The 200 questionnaires were administered by using ground mail, e-mail, and personal visits and 156 questionnaires were returned(82.5% response rate). Social stress, job satisfaction and role conflicts were significantly determined by personal traits and job characteristic variables. However, job stress, organizational commitment and self-efficacy was only significantly determined by job characteristic variables. In social stress and role conflicts, the subjects with challenge, sociability, acceptance and prudence traits were tend to be significantly higher scores compared to the stability traits. Additionally, among social stress regression models, adding job characteristics to the personal traits model, $R^2$ was increased up to 19% and adding personal traits to the job characteristics model, $R^2$ was increased up to 14%. In conclusion, the study found that personal traits and job characteristics are important variables in explaining social stress, job satisfaction and role conflicts, that would have important managerial implications for recruiting, hiring and managing either new or current emergency medical technicians efficiently.

• Journal of the East Asian Society of Dietary Life
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• v.23 no.1
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• pp.85-91
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• 2013

Korean traditional rice wine, Makgeolli, has been widely consumed and increasingly popular in Korea. In this study, we examined Makgeolli supplemented with cranberries (0, 5, 10 and 15% by rice weight) during fermentation for seven days for the various quality characteristics : pH, total acidity, soluble contents, color, reducing sugars, alcohol contents, and DPPH free radical scavenging activities, total flavonoids, microbial properties, and sensory properties. After the pH value decreased from a range of 4.40~5.63 to 3.83~3.94 up to day 3, the pH gradually increased until day 7. As fermentation proceeded, soluble contents and reducing sugar increased in most of the samples, with a temporary reduction after day 2. There were no differences in L and b color values, but the "a" value showed significant differences with the rate of cranberry added. The DPPH free radical scavenging activity and total flavonoid content of cranberry Makgeolli were higher than those of the control. After fermentation for seven days, the alcohol content ranged from 14.57 to 17.40%, while total acidity levels were within the range of 0.50 to 0.54%. Yeast cell counts increased until day 3 and then, gradually deceased. In the sensory evaluation, Makgeolli with 10% cranberry showed the highest overall acceptance.

• Journal of Digital Convergence
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• v.14 no.10
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• pp.303-310
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• 2016

Due to the ossification of the Internet, it is difficult to accommodate variety services. One of the efficient solution to this problem is network virtualization. It allows multiple parallel virtual networks to run on the shared physical infrastructure. It needs new resource allocation mechanism to share efficient physical resources. In this paper, we present efficient bandwidth allocation algorithm for virtual network request with high service priority. Our proposed algorithm can withdraw allocated bandwidth from low-level priority virtual network and maintain low-level virtual network service. We evaluated the performance of our proposed algorithm using simulation and found the improvement of approximately 8% acceptance rate.

• Korean Journal of Child Studies
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• v.32 no.4
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• pp.203-216
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• 2011

The purpose of this study was to investigate the relationships between mothers' parental intelligence and children's abilities of self-control and empathy. 180 children aged 5 were selected from 4 kindergartens in G city. The gender breakdown for the sample group was as follows : boys comprised 60.0% (108) and girls comprised 40.0% (72) of the total sample. The Parental Intelligence Scales (PIS) was used to rate mothers' parental intelligence. Children's self-control and empathy were also measured. The SPSS 12.0 program was used for the purposes of analyzing the data. The results of the study were as follows. Firstly, mothers' parental intelligence was related in a general sense with children's self-control. However, such a relationship did not appear between rejection in the area of parental intelligence and self appraisal in self-control, nor did it appear between acceptance in intelligence and emotion in self-control. Secondly, the variable of encouragement was the only one in evidence in terms of mothers' parental intelligence and how it was related with children's empathy.