• Nuclear Engineering and Technology
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• v.20 no.2
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• pp.88-104
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• 1988

The FUel Rod Analysis(FURA) code is developed using two-dimensional finite element methods for axisymmetric and plane stress analysis of fuel rod. It predicts the thermal and mechanical behavior of fuel rod during normal and load follow operations. To evaluate the exact temperature distribution and the inner gas pressure, the radial deformation of pellet and clad, the fission gas release are considered over the full-length of fuel rod. The thermal element equation is derived using Galerkin's techniques. The displacement element equation is derived using the principle of virtual works. The mechanical analysis can accommodate various components of strain: elastic, plastic, creep and thermal strain as well as strain due to swelling, relocation and densification. The 4-node quadratic isoparametric elements are adopted, and the geometric model is confined to a half-pellet-height region with the assumption that pellet-pellet interaction is symmetrical. The pellet cracking and crack healing, pellet-cladding interaction are modelled. The Newton-Raphson iteration with an implicit algorithm is applied to perform the analysis of non-linear material behavior accurately and stably. The pellet and cladding model has been compared with both analytical solutions and experimental results. The observed and predicted results are in good agreement. The general behavior of fuel rod is calculated by axisymmetric system and the cladding behavior against radial crack is used by plane stress system. The sensitivity of strain aging of PWR fuel cladding tube due to load following is evaluated in terms of linear power, load cycle frequency and amplitude.

• Korea journal of population studies
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• v.28 no.2
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• pp.219-243
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• 2005

This paper reviews research outputs in Korea Journal of Population Studies (KJPS) and the changes in their contents during the period of 1977-2004. In the early years of KJPS, various types of outputs were published, but changes have been made into a direction that research articles compose the main context of the journal. As the journal published twice a year, the total number of articles of the journal shows a trend of marked rise. An analysis of the themes of articles shows that the trend of research in Korean demography has changed hand in hand with transformations of the Korean society. The traditional topics such as population policy, fertility, mortality, and migration were popular before. Labor force, nuptiality, family, aging, regional studies are found to be more popular themes of research recently. Reflecting academic and social demands, KJPS has a broaden range of authors, such as professor, researcher, a government employee, post-doc, and graduate students. The articles written by those working in universities have increased continuously, while research outputs of research institutes have decreased recently. The data for analysis used in articles are varied from but concentrated in some materials - census, vital statistics and various survey data. In early years of KJPS, relatively simple techniques of analysis were adopted in the majority of articles. However, more sophisticated techniques including applied regression analysis, logistic analysis and analysis of survival ratio turn out to be more popular recently. Finally, several suggestions for the future research are presented in this paper.

• Korean Journal of Food Science and Technology
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• v.42 no.6
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• pp.743-749
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• 2010

The present study was conducted to evaluate the effects of resistant starches (RS2, RS3) on weight change and defecation states in rats with constipation induced by loperamide. Sixty male Sprague-Dawley rats were divided into the following six groups: normal control-5% cellulose (NC), constipated-5% cellulose (CC), constipated-5% pectin (CP), constipated-5% RS2 (CR2), constipated-8% RS2 (CR2-H) and constipated-5% RS3 (CR3). The animals were fed AIN76-based experimental diets for 5 weeks. Supplementation of RS2 and RS3 resulted in significantly lower feed efficiency ratios and body weight gain as compared to cellulose supplemented group. Large intestine length was significantly longer in the resistant starch and cellulose groups than in the pectin group. Relative fecal weight to feed intake was significantly higher in the RS3 resistant starch group than in the pectin group, and the appearance of feces was similar to that of the cellulose group. Supplementation of RS3 or cellulose significantly shortened gastrointestinal transit time in the constipated rats as compared to pectin. The results of the present study demonstrated that resistant starch supplementation, especially RS3, may help in depress body weight gain and alleviate constipation through an increase of fecal weight and shortening gastrointestinal transit time in constipated animals.

• Journal of Life Science
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• v.22 no.10
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• pp.1399-1406
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• 2012

The present study was conducted to evaluate the effects of various extracts of Hizikia fusiforme on the anti-obesity effects in 3T3-L1 preadipocytes. We used H. fusiforme extracts from ethanol (EEHF), dichloromethane (CFHF), ethyl acetate (EAFHF), butanol (BFHF), and water (WFHF). Treatment with these extracts significantly suppressed terminal differentiation of 3T3-L1 preadipocytes in a dose-dependent manner as confirmed by a decrease in lipid droplet content through Oil Red O staining; this effect was higher in WFHF than in other extracts. The concentrations of cellular triglyceride were also reduced in 3T3-L1 cells by exposure with these extracts, especially when compared with the controls. Treatment with 200 ${\mu}g/ml$ of WFHF and CFHF caused approximately 42.6% and 23.7% reduction, respectively. In addition, the extracts of H. fusiforme significantly reduced the expression levels of key pro-adipogenic transcription factors, including peroxisome proliferator-activated receptor ${\gamma}$ ($PPAR{\gamma}$) and CCAAT/enhancer binding proteins ${\alpha}$ (C/$EBP{\alpha}$) and C/$EBP{\beta}$ as compared with controls. Accordingly, our data indicated that WFHF has a preeminent effect on inhibition of adipocyte differentiation among various extracts, and H. fusiforme extracts may be an ideal candidate for obesity relief.

• Journal of Preventive Medicine and Public Health
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• v.34 no.1
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• pp.1-8
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• 2001

Objectives : To gather information about the factors which influence the interest and intention of admission into charging nursing hones for the elderly(CNH), as these homes represent an important method for resolving the problems related to the rapid population aging occurring in Korea. Methods : A face-to-face interview survey was carried out with 320(men 159, women 165) patients over 60 years old who were admitted at 2 university hospitals and 5 general hospitals in the Busan area between December 1998 and March 1999. Data were analyzed through t-test, ANOVA, correlation and multiple regression analysis. Results : The mean age and years of education of the study population was 67.0 and 7.7 years, and the types of chronic degenerative disease included musculoskeletal disorders(20.1%), cerebrovascular disease(17.1%), and diabetes(14.3%). The major forms of household living arrangement prior to admission were elderly alone(22.6%), and elderly couple(33.5%), while about half of them(55.5%) didn't want to live with their children id the future. Almost half were paying medication fees by themselves(46.6%). The level of actual intention of admission$(3.07{\pm}1.39)$ into a CNH was lower than that of interest$(3.22{\pm}1.33)$(p<0.01). Multiple analysis revealed that the intention of admission increased with decreasing number of future supportive persons$(\beta=-0.107)$, lower level of activity in daily life$(\beta=-0.447)$, and longer years of education$(\beta=-0.447)$ with 32.7% of $R^2$. As for the factors which determined the admission into a CNH, the fee and facilities were considered to be most important, and professional nursing and physician's care were the most desired services. In nomenclature, they preferred 'elderly hospital' or 'elderly health center' to CNH. Conclusions : Interest in CNH is increasing recently, but existing studies about patient experiences in CHN are still limited. This study may form a basis for future examinations of the needs and uses for CNH. Active financial support and public information are considered by the authors to be important factors for the induction of welfare services for the elderly, though CNH.

• Korean Journal of Construction Engineering and Management
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• v.15 no.4
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• pp.39-48
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• 2014

The speed of aging society is increasingly getting faster in Korea. Currently, there are over one million elderly living alone, which represents more than 19% of the total elderly in Korea. Although various policies and research have been implemented for caring the elderly living alone, there have been obvious limitations in realization of the caring system due to inconvenience, privacy violation, difficult operation and maintenance. Therefore, the objective of this study is to develop a method and a prototype system to monitor safety of elderly living alone by using energy usage information of automatic meter reading device. The proposed system is expected to improve or resolve the existing limitations and to provide 24 hour monitoring and early detection of death for the elderly living alone without adding staffs for operation and maintenance in a more effective and economic way.

• Journal of Technologic Dentistry
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• v.34 no.3
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• pp.291-302
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• 2012

Purpose: It is to survey old men's utilization status of dental clinic and temporary-binding dentures and then to provide basic data to make a program for manufacturing old men's dentures and their teeth health education. Methods: Random selection was made on old men living in Daejeon and Chungnam, and a survey was conducted from April 15 to May 20, 2011. 500 questionnaires were distributed and 420 questionnaires were collected. Using spss 18.0 program, final analysis was made on 363 questionnaires except for 57 questionnaires which had missing value or showed some doubts about the unreliability. Results: 1. With respect to number of natural teeth as per the age, the upper/lower jaws had meaningful differences (P<.001), which means that the older the person is, the smaller number of natural teeth is. In the meantime, there was no meaningful difference according to sex. 2. With respect to kind of prosthetics installed in a mouth as per the age, there was meaningful difference in the upper jaws (P<.05) but there was no meaningful difference in the lower jaws. It was found out that the older the persons are, the more they use removable dentures while the younger the persons are, the more they use fixed partial dentures. 3. With respect to mouth health condition recognized by oneself, it showed bad (44.4%) and good (10.3%),which means recognition as bad is greater, and the age when prosthetics were first used is dispersed variously from below 40 to over 70. 4. Dental care institutions which they mainly used are hospital and clinics (91.5%), and 66.4% of them visited dental clinics lately. Preferential treatment if they go to dentists is as follows in the order of prosthetics (33.9%), gum treatment (24.2%) and pain treatment (14.9%). 5. 68.4% of them revisited dentists after installation of dentures and the reason for revisit is as follows in the order of poorly fitted dentures (35.1%), painful gum 25.9%, regular check-up 25.4% and difficult chewing 9.6%. Conclusion: As our country enters into an aging society, mouth health problem of old men has come to a serious issue, and therefore, a survey was conducted on some old men with respect to their utilization status of dental clinic and removable dentures in order to provide basic data for improvement of quality of their life, maintenance and enhancement of their mouth health. The study result shows that the older they are, the higher the loss rate of teeth as well as needs for prosthetics are, and thus it is thought the study will help to develop mouth health education program which may improve quality of old men's life by recovery of mouth functions declined due to loss of teeth and by regular check-up, education for mouth health control and following-up control of dentures.

• Korean Journal of Food Science and Technology
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• v.40 no.2
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• pp.238-242
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• 2008

In this study, hydrogen sulfide ($H_2S$) production was examined during beer fermentation using two ale and two lager yeast strains. In the lager yeast fermentation, a large amount of $H_2S$ was produced in the early fermentation stages when the yeast were actively fermenting wort, indicating a positive relationship between the level of H2S production and the yeast growth rate during fermentation. The ale yeasts produced much lower levels of H2S than the lager yeasts. In the lager fermentation, a higher fermentation temperature shortened the fermentation period, but much higher levels of $H_2S$ were produced at higher temperatures. American pilsner lager yeast fermenting at $15^{\circ}C$ produced a relatively high level of $H_2S$ at the end of fermentation, which would require a longer aging time to remove this malodorous volatile sulfur compound. Not including the English ale strain, which produced a higher level of H2S at lower temperatures, the ale yeast produced lower levels of $H_2S$ at lower temperatures, suggesting that each strain has an optimum fermentation temperature for H2S production.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.13 no.4
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• pp.73-85
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• 2014

Approaching to aging society with increasing transportation vulnerable, most developed countries has positively promote low-floor bus. Such circumstance in Korea has plan to introduce low-floor bus to intra-city bus system which accounted for 30 percent of total number of buses however there is no specific operating plan for this matter. According to the revealed preference study on bus service, the study shows that the efficiency of low-floor is relatively low than that of other buses, therefore, it is necessary to establish feasible plan for bus route selection. Thus, this study is to conduct research on analyzing trip characteristics of transportation vulnerable and establish bus route selection measures for low-floor bus. The result from the survey in Jeollabuk-do Province reveals that the trip purpose of transportation vulnerable is mainly for welfare and medical service, which was made less than 6 times a week. Futhermore, 37.6 percent of transportation vulnerable use buses, thus, it is essential to improve its service quality for enhancing user's convenience and safety. In that transportation vulnerable O-D needs to be established and forecasts future demand for selecting optimal bus route. According to the estimation, route passing through densely populated areas with transportation vulnerable should take the first priority, city circular and other route would be next. Moreover, it is economically efficient that areas populated more than 200,000 with fixed route and less than 200,000 with limited route responsive to demands would be feasible plans. This study will have greater an impact on transportation planning and further research on transportation vulnerable.

• Journal of Trauma and Injury
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• v.28 no.2
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• pp.60-66
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• 2015

Purpose: Cultivator accidents are frequent and often lead to abdomino-perineal organ injury and, if severe, to death. This study presents the clinical characteristics, outcomes, and factors associated with mortality in patients who sustained an abdomino-perineal organ injury in cultivator accidents. Methods: We retrospectively analyzed the records of 53 patients who visited the emergency department of a tertiary hospital with abdomino-perineal organ injuries caused in cultivator accidents from April 2005 to March 2010. Results: All 53 patients had visited other medical institutions before visiting our hospital. Their mean age was $64.0{\pm}11.1$ (range, 20-80) years and 32 (60.4%) patients were 65 or older. The male-to-female ratio was 46:7. The chief complaint was abdominal pain (38 cases, 71.7%). The 53 patients included 41 cultivator operators (77.4%), 11 passengers (20.8%), and 1 passerby (1.9%). The causes of the injuries included a direct impact of the handlebar in 20 cases (37.7%), a rollover in 21 cases (39.6%), a fall in 10 cases (18.9%), and a wheel in two cases (3.8%). Several of the 53 patients had injuries to multiple abdomino-perineal organs, and the injured organs included the liver (23 cases, 26.4%), spleen (16 cases, 18.4%), pancreas (7 cases, 8.0%), small bowel (7 cases, 8.0%), mesentery (6 cases, 6.9%), adrenal gland (5 cases, 5.8%), and other organs. According to the abbreviated injury scale (AIS) dictionary, a thoracic injury was the most frequent co-injury (33 of 53 cases, 62.3%). Abdomino-perineal surgery was performed in 31 cases (58.8%) and angio-embolization was performed for six liver and two kidney injuries. Thirteen patients died (24.5%); all were males. The Injury Severity Scale (ISS) was lower in the survivors ($17.8{\pm}8.5$ vs. $27.0{\pm}16.0$; p=0.010). Conclusion: With the aging of agricultural workers, safety education programs should be implemented. Furthermore, the patient transfer system in agricultural areas must be improved.