• Smart Structures and Systems
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• 제14권3호
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• pp.445-468
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• 2014

The objective in this research is to determine the feasibility of using changes on the dynamic properties of a reinforced concrete (RC) structure to identify different levels of seismic induced damage. Damping ratio and natural frequency changes in a RC bridge column are analyzed using different signal processing techniques like Hilbert Transforms, Random Decrement and Wavelet Transforms. The data used in the analysis was recorded during a full-scale RC bridge column shake table test. The structure was subjected to ten earthquake excitations that induced different levels of inelastic demand on the column. In addition, low-intensity white noises were applied to the column in-between earthquakes. The results obtained show that the use of the damping ratio and natural frequency of vibration as damage indicators is arguable.

• Journal of Nutrition and Health
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• 제19권3호
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• pp.169-176
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• 1986

The effect of riboflavin feeding on lipid emtabolism in rat were studied. 70 male Sprague-Dawley rats were divided into 7 diet group ; control, riboflavin, cholesterol, MLHP (methyl linoleate hydroperoxide) cholesterol plus MLHP, cholesterol plus riboflavin, cholesterol plus MLHP plus riboflavin. After 4 weeks formular feeding sera of animals were collected, then checked cholesterol, triglyceride, phospholipid levels and lipoprotein by use of cellulose acetate papter. The results were as follows ; 1) Marked increase of triglyceride and phospholipid levels were found in the group feeding with cholesterol, cholesterol plus MLHP. 2) Combined riboflavin feeding prevented the increase of triglyceride and phospholipid levels in the group of cholesterol, cholesterol plus MLPH. 3) Also combined riboflavin feeding prevented the increase of $\beta$-lipoprotein fraction in cholesterol feeding group. Our results demonstrate that riboflavin has an inhibitory effects on the derangements of lipid metabolism due to administration of cholesterol, cholesterol plus MLHP.

• 한국식품과학회지
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• 제14권1호
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• pp.82-93
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• 1982

The use pattern and survey data on the residue levels of organochlorine insecticides in Korea were summarized. On the basis of available data on food consumption and residue levels, the daily intake of the pesticide chemicals by average Korean adults were calculated to give $13.77\;{\mu}g$ of total BHC, $2.45\;{\mu}g$ of total DDT and $4.06\;{\mu}g$ of heptachlor and its epoxide. These intake levels were compared with the acceptable daily intake proposed by FAO/WHO and values obtained in other countries. It was then proposed to undertake a total diet study on pesticide chemicals for the sake of food safety assurrance and reasonable regulation of pesticides for food production in this country.

• 터널과지하공간
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• 제4권1호
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• pp.38-46
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• 1994

This paper concerns the design of blasts adjacent to structures and facilities. In order to investigate the site characteristics, measurements of in-situ wave propagation and laboratory tests of rock cores taken from the boreholes were carried out. Effects of rock media and delay intervals on ground vibration levels were identified from over sixty measurements of three times of test blasts. For practical use in the field, an empirical propagation equation was derived so as to reflect the characteristics of rock media and delay effects. Safe limits of vibration level for structures were conservatively established based on various suggested criteria. Safe limits for facilities were adopted so that vibration levels induced by blasting should not exceed the allowable limits specified in the manufacturer's installation condition. Suggested were blast pattern and operation to enhance the rock fracturing and to reduce the ground vibration levels under the restricted conditions.

• 지식경영연구
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• 제18권1호
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• pp.49-65
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• 2017

Financial products entail either gains or losses, and customers' psychological reaction to these gains and losses affect the selection of the financial products. This study explains the financial customers' behavior by introducing consumers' psychological variables such as loss aversion and construal levels. According to the construal level theory, people use more abstract and higher levels of construal to represent objects that are more distant on psychological distance. Based on extant research about loss aversion and construal levels, this study proposes two hypotheses and test the hypotheses. The experimental study examines how loss aversion affects the choice between deposit products and fund products in short-term and long-term investment situations. In the long-term condition the respondents prefer fund products to deposit products, whereas in the short-term condition the respondents have showed the opposite result. Also, the effects of loss aversion on preferences for financial products have interacted with the time horizon of investments. Implications and limitations are discussed to establish more effective marketing strategies based on the results of this study.

• 한국음향학회지
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• 제18권2호
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• pp.40-47
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• 1999

송신 초음파 음장에서 해상도를 증가시키기 위하여 집속방법을 널리 이용한다. 집속은 영상점이 있는 Mainlobe 방향에서 돌아온 반사 신호의 크기를 증가시키지만, sidelobe에 의한 반사 신호는 상쇄되어 크기가 줄거나 없어진다. 그러나 집속한 뒤에도 sidelobe의 신호가 완전히 제거되지 않을 경우 영상의 해상도를 크게 저하시킨다. 본 논문은 초음파의 음장특성에 따라 수신된 신호를 Fourier transform하여 주파수 영역에서 sidelobe와 null 방향에서 돌아오는 수신신호의 크기를 구하여 비율에 따라 영상값을 scaling함으로써 sidelobe의 영향을 줄여 해상도를 향상시키는 방법을 제안하였다. 제안한 방법을 컴퓨터 시뮬레이션과 실험으로 검증하여 mainlobe의 폭이 줄고 sidelobe가 감소함을 보였다.

• 디지털산업정보학회논문지
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• 제11권4호
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• pp.129-141
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• 2015

This study evaluates user experience of streaming stick service through usability testing. Streaming stick services such as Roku, Chromecast, and Everoncast were tested in ten levels belonging to five usability variables that are composed of efficiency of use, accuracy, meaningfulness, flexibility, and consistency. Each variable has two levels respectively that are responsiveness, minimal action, error prevention, error detection, error recovery, understandability, learnability, substitutivity, predictability, and familiarity in order. Twenty five participants volunteerly joined this research, and the results showed that Roku is superior to another two OTTs in most levels and variables. It implies that participants prefer to remote control, many channels, and personalized service during experiencing the service.

• 보건의료산업학회지
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• 제1권1호
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• pp.45-58
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• 2007

The study is designed to compare differences between male and female Internet users in present Internet use conditions, Internet addition, self-respect, and deviation from a health life and analyze and understand factors causing compulsive Internet use. The research is aimed at suggesting basic information to guide a desirable direction for healthy and effective Internet use. The survey of 456 students majoring in public health at some universities in the Pusan-Kyungnam areas was made in November, 2006. The results are as follows: As for general information on those surveyed the number of the males was 50(11.0%) and that of the females was 406(89.0%), which shows an absolute higher ratio of the female respondents. On a question of Internet use frequency 62% of the male students and 44.6% of the female students answered they use the Internet everyday. Also the male respondents' Internet use time was longer. 64.0% of the male students use the Internet for games and entertainment, which were the highest ranked reason. 64.4% of the female students said they use the Internet to check e-mails. To all the questions assessing Internet addiction, the male users' answers implied higher addiction levels, but there wasn't statistically significant difference. However, the statistically outstanding distinction between the two sexes on deviation from a health life is shown in smoking, cheating in a test, obscene video/books, and conflicts with parents. The most answered deviations among the male respondents are smoking, cheating in a test, and obscene video/books, while conflicting with parents is for the female students. On self-respect the survey has found statistical differences in five questionnaire items and the female showed higher levels in all those questions. The male students answered cheating in a test(0.399), conflicts with parents(0.391), and Internet use time(0.242) have significant plus(+) influences on their compulsive internet use, while alcohol(-0.308) has a minus(-) influence. The female students answered self-respect(0.114), alcohol(0.097), obscene video/book (0.218), conflicts with parents (0.243), and Internet use time (0.284) factors have plus(+) effects.

• 대한수학회지
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• 제59권1호
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• pp.35-51
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• 2022

We give secure parameter suggestions to use sparse secret vectors in LWE based encryption schemes. This should replace existing security parameters, because homomorphic encryption (HE) schemes use quite different variables from the existing parameters. In particular, HE schemes using sparse secrets should be supported by experimental analysis, here we summarize existing attacks to be considered and security levels for each attacks. Based on the analysis and experiments, we compute optimal scaling factors for CKKS.

• 한국농촌간호학회지
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• 제8권2호
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• pp.65-73
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• 2013

Purpose: The purpose of this study was to identify the relationship between intention to use advance directives and level of death anxiety in community-dwelling elders. Method: The participants were 200 older adults who were aged 60 or over and attended the community welfare centers. The level intention to use advance directive was measured by a questionnaire that was developed by the authors for the study. The measure by Kraus and Ellisond was administered to evaluate the level of death anxiety. Result: The average score for intention to use advance directives was $2.05{\pm}0.88$ and that of death anxiety was $6.2{\pm}2.28$. There were significant differences in the intention to use advance directives according to education levels and individual properties. Although there was no significant relationship between the intention to use advance directives and the level of death anxiety, they were negatively associated. Therefore, older adults who had lower death anxiety would tend to use advance directives. Conclusion: It would be necessary to screening the level of death anxiety to promote use of the advance directives. In addition, education programs for advance directives would be essential to consider about advance directives for their end-of-life especially for the community-dwelling elderly in Korea.