고주파 저스트레인 골자극 인가용 진동 시스템 개발

유주연,박근철,전아영,김윤진,노정훈,전계록,Yoo, Ju-Yeon,Park, Guen-Chul,Jeon, Ah-Young,Kim, Yun-Jin,Ro, Jung-Hoon,Jeon, Gye-Rok 대한의용생체공학회 2011 의공학회지 Vol.32 No.2

In this study, the system for application of the bone stimulation was implemented using high frequency and low strain method. The whole system consists of the high frequency and low strain vibration stimulation system 177 for stimulating bone, LVDT sensor, and wireless sensor based on tri-axial accelerometer. To evaluate the usefulness of the system, the frequencies and accelerations from function generator were applied to the vibration stimulation system. The range of frequency was 17 Hz, 30 Hz, 45 Hz, 50 Hz and the range of acceleration was set 0.3 g, 0.6 g, 1g, and 2 g. The measured frequencies and acceleration using LVDT (linear variable difference transformer) sensor and 3-axial accelerometer were estimated and compared. The range of frequencies average difference was from 0.0 to 0.004 Hz. As the standard deviation of frequencies estimated by LVDT sensor and accelerometer was below 0.03 Hz and the output frequencies of function generator were similar: Also the results of t-test were satisfied with conditions of p > 0.05. And the acquired frequencies and acceleration from vibration measuring device module were estimated and analyzed. As the mean of accelerations was similar to the acceleration applied from function generator. And the standard deviation of acceleration estimated from vibration measuring device module was ranged from 0.019 g to 0.038 g. Also the results of t-test were satisfied with conditions of p > 0.05. Therefore, these results were airy similar to the acceleration applied from function generator. As a result, the usefulness of the system was confirmed. n a further study, clinical experiment will be carried out with the authorization of IRB (institutional review board) so that appropriate frequency and strain would be investigated in clinical field.

LTCC 전극공정부산물 침출 용액으로부터 은 회수 및 은 나노입자 제조

유주연,강유빈,박진주,류호진,윤진호,이근재,Yoo, Juyeon,Kang, Yubin,Park, Jinju,Ryu, Hojin,Yoon, Jin-Ho,Lee, Kun-Jae 한국분말야금학회 2017 한국분말재료학회지 (KPMI) Vol.24 No.4

There has been much interest in recycling electronic wastes in order to mitigate environmental problems and to recover the large amount of constituent metals. Silver recovery from electronic waste is extensively studied because of environmental and economic benefits and the use of silver in fabricating nanodevices. Hydrometallurgical processing is often used for silver recovery because it has the advantages of low cost and ease of control. Research on synthesis recovered silver into nanoparticles is needed for application to transistors and solar cells. In this study, silver is selectively recovered from the by-product of electrodes. Silver precursors are prepared using the dissolution characteristics of the leaching solution. In the liquid reduction process, silver nanoparticles are synthesized under various surfactant conditions and then analyzed. The purity of the recovered silver is 99.24%, and the average particle size of the silver nanoparticles is 68 nm.

폴리올 공정과 액상 환원 공정에 따른 은 입자 제조 및 특성 평가

유주연,장효성,이근재,Yoo, Juyeon,Jang, Hyosung,Lee, Kun-Jae 한국분말야금학회 2016 한국분말재료학회지 (KPMI) Vol.23 No.4

Ag nanoparticles are extensively studied and utilized due to their excellent catalysis, antibiosis and optical properties. They can be easily synthesized by chemical reduction methods and it is possible to prepare particles of uniform size and high purity. These methods are divided into vapor methods and liquid phase reduction methods. In the present study, Ag particles are prepared and analyzed through two chemical reduction methods using solvents containing a silver nitrate precursor. When Ag ions are reduced using a reductant in the aqueous solution, it is possible to control the Ag particle size by controlling the formic acid ratio. In addition, in the Polyol process, Ag nanoparticles prepared at various temperatures and reaction time conditions have multiple twinned and anisotropic structures, and the particle size variation can be confirmed using field emissions scanning electron microscopy and by analyzing the UV-vis spectrum.

초등학교 급식에서 채소류 메뉴의 선호도 및 기호도에 관한 연구

유주연(Yoo, Joo Yeon),김효연(Kim, Hyo Yeon) 한국식공간학회 2012 식공간연구 Vol.7 No.1

The purpose of the study was to investigate the basic data that could make out a menu reflected by students' preference to increase the intake of vegetable food through the cooking method and color of favorite vegetables. For the investigation, 292 primary school students in Gyeonggi area were surveyed. In the preference of food items, the meat food was more preferred to the vegetable food. Also, the reasons that students do not eat vegetable provided were 'bad taste' and 'unfavorite vegetable'. The preference analysis for vegetable showed that green vegetables, white vegetables and yellow vegetables were in the order of cucumber, cabbage, Chinese cabbage and spinach; potato, radish, onion and root of Chinese bellflower and sweet potato, sweet pumpkin, bean sprout and carrot, respectively. The preference was three kinds of vegetables that were more delicious rather than frequently eaten at home. The preference analysis for cooking method of vegetables showed that green, white and yellow vegetables were in the order of seasoned vegetables, raw seasoned vegetables and salads; fried food, pan-fried foods and soups/stews; fried food and steamed of foods, respectively. Therefore, this study was conducted in order to increase the vegetable intake. According to the results of this study, it is certainly necessary to develop menus of vegetables integrating the kind and its cooking methods both students preferred and disliked. This suggests that the use of vegetables and the development of more efficient cooking methods for less preferred vegetables is needed. Furthermore, schools need to develop various nutrition programs for both students and parents. This would improve parents' knowledge in nutrition and enhance the formation of healthy and balanced eating habits for students.

생태학적 변인이 영아의 사회적 적응에 미치는 영향

유주연(Yoo, Jooyun) 한국영유아보육학회 2018 한국영유아보육학 Vol.0 No.113

본 연구는 영아의 사회적 적응에 대해 살펴보고 이에 영향을 주는 생태학적 변인에 대해 알아보았다. 서울과 경기도 지역 어린이집 만 1, 2세 영아 150명(남아 78명, 여아 72명)을 대상으로 이들의 어머니와 담임교사 49명을 통해 자료를 수집하였다. 자료는 기술통계, 상관분석, 위계적 회귀분석을 통해 분석되었다. 연구결과는 첫째, 영아의 사회적 적응에서 정서적응 점수가 또래나 성인 상호작용에 비해 상대적으로 높았다. 둘째, 독립변수인 생태학적 변인들과 종속변수인 영아의 사회적 적응 간에는 각 변인 간 상관이 나타났다. 셋째, 영아의 기질은 영아의 사회적 적응을 가장 많이 설명하였으며 미시체계인 영아-교사 관계와 중간체계인 부모-교사 관계 역시 영아의 사회적 적응에 유의미한 영향을 미쳤다. 본 연구는 영아를 둘러싼 사회적 환경이 영아의 사회적 적응에 체계적으로 영향을 미치고 있음을 밝혔으며, 이는 영아의 사회적 발달을 위해서 부모와 교사간의 협력을 강화하는 등 다차원적으로 접근해야 함을 시사한다. The purpose of this study was to examine toddlers’ social adjustment and to figure out the effects of the ecological variables affecting to it. Data were gathered from the mother of 150 toddlers(78 boys, 72 girls)and 49 teachers from 15 day-care centers. Data were analyzed by descriptive statistics, correlation analysis, and hierarchical regression analysis. The results of this study were as follows: First, the emotional adjustment score of social adjustment was relatively higher than peer and adult interaction scores. Second, the correlations among variables were significant. Third, toddlers’ temperament explained toddlers" social adaptation the most. Toddler - teacher relationship and mother - teacher relationship also significantly affected toddlers’ social adjustment. The results of this study suggest that the social systems surrounding toddlers systematically affects the toddlers’ social adaptation. It implies that we needs to approach multi-dimensionally to help toddlers’ social development such as strengthening cooperation between the parents and the teachers.

육상 시뮬레이터의 기반의 자율운항 선박 시나리오 개발

유주연(Ju-Yeon Yoo),황훈규(Hun-Gyu Hwang),김정훈(Jung-Hun Kim),김동욱(Dong-Wook Kim) 한국통신학회 2022 한국통신학회 학술대회논문집 Vol.2022 No.11

혈관성 치매노인에게 있어 12주간의 요가운동이 혈압, 체력 및 혈액변인에 미치는 영향

유주연(Ju Yeun Yoo),이난희(Nan Hee Lee),이청무(Chung Moo Lee),김민정(Min Jeong Kim) 한국발육발달학회 2010 한국발육발달학회지 Vol.18 No.3

The purpose of this study was to investigate the effect of Yoga exercise on blood pressure, physical fitness, and blood variables in elderly with vascular dementia. Twelve elderly with vascular dementia in nursing home volunteered in this study. All subjects were each vascular dementia patient were randomly divided into Yoga exercise group(N=7) and control group(N=5). In Yoga exercise group participated in Yoga exercise that consisted of 20~50% HRR intensity for 12 week(3days per week), meanwhile maintain their daily life in control group. Through statistical analysis on paired t-test and independent t-test, following results that SBP (systolic blood pressure), TC(total cholesterol), TG(triglyceride) were decreased whereas muscle strength, muscle endurance, endurance capacity, body flexibility, epinephrine, norepinephrine, serotonin was increased significantly after Yoga exercise training. In control group after 12 weeks, TC, norepinephrine, serotonin were significantly increased, Also SBP and endurance capacity were significantly different between groups. These findings indicate that Yoga exercise training was effective to prevent vascular dementia risk factors and to retard the velocity of vascular dementia.

부모-교사 관계가 영아기 자녀를 둔 어머니의 양육효능감에 미치는 영향

유주연(Jooyun Yoo) 한국보육지원학회 2018 한국보육지원학회지 Vol.14 No.4

Objective: The purpose of this study was to examine the effects of parentteacher relationships on mothers’ parenting efficacy especially for toddlers. Methods: 225 mothers of toddlers completed questionnaires on parent-teacher relationships and parenting efficacy. This study used technical statistics, Pearson’s correlation analysis, and multiple regression analysis in order to analyze the collected data. Results: First, there was a significant correlation between parent-teacher relationships and mothers’ parenting efficacy. Second, the parent-teacher relationships was an important factor in predicting mothers’ parenting efficacy. In particular, when a teacher and mother develop practical collaboration for caring for and educating a child, the mothers’ parenting efficacy was higher. Conclusion/Implications: These findings indicate that the parent-teacher relationship is a significant factor in order to improve the quality of parenting. The results especially support the importance of collaboration between teachers and parents and suggest that we need to find practical ways for collaborating in the field. Limitations of this study and implications for future research were discussed

영아의 기질과 영아-교사 관계에서 부모-교사 협력의 조절효과

유주연(Jooyun Yoo) 한국열린유아교육학회 2018 열린유아교육연구 Vol.23 No.5

본 연구는 영아의 기질적 특성인 부정적 정서성과 의도적 통제가 영아-교사 관계에 미치는 영향을 부모-교사 협력이 조절하는가에 대해 알아보았다. 서울과 경기도 지역어린이집 16곳의 교사 41명을 대상으로 그들이 담임을 맡고 있는 영아 123명(남아 67명, 여아 56명)에 대한 자료를 수집하였다. 자료 분석은 기술통계와 t-test를 실시하였고, 위계적 회귀분석을 통해 조절효과를 검증하였다. 연구결과는 첫째, 영아의 기질 중 의도적 통제와 영아-교사 친밀관계에 있어서 성차가 뚜렷이 나타났다. 둘째, 영아의 부정적 정서성과 의도적 통제, 부모-교사 협력은 영아-교사 갈등 관계에 유의한 영향을 미치며, 특히 부모-교사 협력은 부정적 정서성이 영아-교사 갈등 관계에 미치는 영향을 조절하는 것으로 나타났다. 반면, 영아-교사 친밀관계에는 영아의 기질인 의도적 통제만이 유의한 영향을 미치는 것으로 나타났다. 이는 발달에 있어서 취약한 기질적 특성이라 할 수 있는 부정적 정서성이 영아-교사 갈등관계에 미치는 영향에 부모-교사 협력이 보호요인으로 작용할 수 있음을 의미하며, 보육현장에서 부모의 참여가 영아의 생활과 발달에 영향을 주고 있음을 시사한다. The purpose of this study is to investigate the effect of temperamental characteristics, such as negative affect and effortful control on toddler-teacher relationship and to examine the moderating effect of parent-teacher cooperation. A total of 41 teachers of 123 infants (67 boys, 56 girls) were recruited from 16 day care centers in Seoul and Gyeonggi provinces. Descriptive statistics and t-test and hierarchial regression were used to analyze the collected data. The results were as following. First, there was a clear difference between effortful control of toddlers’ temperament and toddlerteacher intimacy. Second, toddlers’ negative affect, toddlers’ effortful control, and parent-teacher cooperation have significant influences on toddler-teacher conflict, and especially parent-teacher cooperation appeared to moderate the influence of negative affect on toddler-teacher conflict. On the other hand, toddler - teacher intimacy is shown to be significantly influenced only by infant temperament, effortful control. This implies that parent-teacher cooperation can be a protective factor for the influence of negative affect, a potential vulnerable temperament characteristic, on toddler-teacher conflict relations. It suggests parent involvement influences toddler’s daily life and development.

CAPM의 서울 아파트 시장 적용 및 활용에 관한 기초연구

유주연 ( Joo Yeon Yoo ),이준용 ( Jun Yong Lee ),손재영 ( Jae Young Son ) 한국부동산분석학회 2010 不動産學硏究 Vol.16 No.2

This study tests the theoretical equilibrium described by CAPM(capital asset pricing model) using micro-data from Seoul`s apartment market. Implications of CAPM is derived, and tested for two distinct submakets of Seoul using the methodology proposed by Black, Jensen and Scholes(1972). Returns from individual apartment investment are calculated from monthly apartment price data, and market rates of return are assessed from price indices surveyed by Kookmin Bank. 3 month CD interest rates are used as risk-free rates of return. Our test shows that CAPM is not strictly applicable in the overall market. The result was expected to a certain extent, considering many elements of inefficiency in the real estate market. However, both submarkets show fairly linear relationship between beta coefficients and excess rates of return. It implies that although the broad Seoul housing market differs from what CAPM presumes, individual submarkets may move in a more rational and efficient way.