• 한국재료학회지
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• 제28권4호
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• pp.214-220
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• 2018

We report on the fabrication and photoelectrochemical(PEC) properties of a $Cu_2O$ thin film/ZnO nanorod array oxide p-n heterojunction structure with ZnO nanorods embedded in $Cu_2O$ thin film as an efficient photoelectrode for solar-driven water splitting. A vertically oriented n-type ZnO nanorod array was first prepared on an indium-tin-oxide-coated glass substrate via a seed-mediated hydrothermal synthesis method and then a p-type $Cu_2O$ thin film was directly electrodeposited onto the vertically oriented ZnO nanorods array to form an oxide semiconductor heterostructure. The crystalline phases and morphologies of the heterojunction materials were characterized using X-ray diffraction and scanning electron microscopy as well as Raman scattering. The PEC properties of the fabricated $Cu_2O/ZnO$ p-n heterojunction photoelectrode were evaluated by photocurrent conversion efficiency measurements under white light illumination. From the observed PEC current density versus voltage (J-V) behavior, the $Cu_2O/ZnO$ photoelectrode was found to exhibit a negligible dark current and high photocurrent density, e.g., $0.77mA/cm^2$ at 0.5 V vs $Hg/HgCl_2$ in a $1mM\;Na_2SO_4$ electrolyte, revealing an effective operation of the oxide heterostructure. In particular, a significant PEC performance was observed even at an applied bias of 0 V vs $Hg/HgCl_2$, which made the device self-powered. The observed PEC performance was attributed to some synergistic effect of the p-n bilayer heterostructure on the formation of a built-in potential, including the light absorption and separation processes of photoinduced charge carriers.

• 인지과학
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• 제26권2호
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• pp.241-261
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• 2015

본 연구에서는 만 5-6세 아동들의 타인-타인 또는 자신-타인 간 자원 분배 결정에 수혜자의 소속집단(내집단 대 외집단)이 영향을 미치는지를 검증하였다. 실험 1에서는 아동이 자원 분배의 수혜자가 되지 않고 친구(내집단)와 낯선 아동(외집단)에게 스티커를 나누어주는 분배자의 역할만을 수행한 게임을 진행하였다. 이 때 아동은 낯선 아동보다 친구에게 더 많은 스티커를 나누어주었고, 이는 아동 자신이 분배의 이해 당사자가 아닌 경우에는 내집단에게 더 호의적으로 분배를 한다는 것을 보여주었다. 실험 2에서 아동은 상대방이 친구 혹은 낯선 아동인 상황에서 자기 자신과 상대방에게 스티커 10개를 분배하는 게임에 참여하였다. 이러한 자기-타인 분배 상황에서 아동들은 상대방이 내집단 또는 외집단 구성원인지에 관계없이 이기적인 분배를 하는 양상을 보였다. 이는 자기 자신이 자원 분배의 당사자가 되었을 경우에는 내집단을 선호하는 경향성을 나타내지 않았음을 보여주었다. 본 연구는 기존 성인 연구에서 관찰되어온 자원 분배 행동에서의 내집단 편향의 발달 과정에 대한 추가 자료를 제공한다.

• 노동경제논집
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• 제25권1호
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• pp.131-160
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• 2002

교육훈련의 경제적 효과에 대해서 한국노동패널을 자료를 이용하여 개인별로 살펴본 결과 본고에서는 다음과 같은 결과를 얻을 수 있었다. 교육훈련의 임금효과는 근속의 두 배에 조금 미칠 정도로 크고 유의하게 나타난다. 교육훈련은 직무내용과 고용안정, 성장 가능성의 만족에 크고 유의한 양의 효과를 갖는 것으로 나타난다. 선택편의를 통제하기 위해 임금함수의 1계차분으로 추정한 교육훈련의 임금효과는 유의하지 않다. 그러나 계속근속자와 이직경험자의 샘플로 나누어 추정하면 계속근속자의 교육훈련의 임금효과는 유의하지 않으나, 이직 경험자의 교육훈련 임금효과는 크고 유의하게 나타난다. 보다 구체적으로 기업의 비용을 부담한 교육훈련의 효과를 보면 이직 경험자의 교육훈련 임금효과는 그고 유의하게 나타나나, 계속근속자의 교육훈련 임금효과는 작고 유의하지 않게 나타난다. 이는 사용자들이 재직근로자가 교육훈련을 이수한 경우 그에 따라 임금을 올려 주지 않은 결과이다. 기업이 비용부담을 하는 경우에 교육훈련으로 인한 생산성 증가만큼 임금 증가가 이루어지지 않는 것은, 결국 기업이 교육훈련 비용부담을 개별 근로자들에게 전가하고 있음을 나타낸다고 할 수 있다.

• 셀메드
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• 제5권1호
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• pp.4.1-4.4
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• 2015

Yoga is an ancient Indian system of life, encompassing various practices including practices for self-discipline and also for regulating the health states of the individual, being practiced for thousands of years. The present study aims at understanding the effect of two high frequency breathing practices over autonomic nervous system. Forty healthy male volunteers of age $21{\pm}2$ years with $9{\pm}3$ months of Yoga practice experience were recruited. The two high frequency Yoga breathing practices, kapalabhati (KB) and bhastrika (BH) were given as interventions randomly on either of the two days to minimise laboratory bias. They were assessed before and immediately after the interventions for heart rate, respiratory rate, heart rate variability (HRV), blood pressure and peripheral oxygen saturation. There was a significant increase in heart rate (p<0.01; p<0.001), systolic blood pressure (p<0.01; p<0.001), NN50 (p<0.01; p<0.001) component of HRV for both KB and BH groups respectively. There was a significant reduction in respiratory rate in both the groups (p<0.001, and p<0.05, BH and KB respectively) immediately following intervention. A significant increase in LF component of HRV and reduction in Diastolic blood pressure and high frequency (HF)component following KB was also observed (p<0.05, for all comparisons). The Mean peripheral oxygen saturation remained unaltered in both the groups (p>0.05).The results suggest that high frequency yoga breathing practices induce physiological arousal immediately as evidenced by increased blood pressure and heart rate. The sympathetic arousal was more following KB session as evidenced by an increased diastolic blood pressure, LF power and a decrease in HF power of HRV as compared to the BH session.

• 한국언론정보학보
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• 제82권
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• pp.7-28
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• 2017

이 논문은 민주주의의 위기와 저널리즘의 상관성을 분석하고, 그에 근거해 미디어 비평이 '민주주의 유지와 성숙'을 견인하는 학술 운동으로 새롭게 자리매김해야 한다는 주장을 담고 있다. 한국 민주주의가 절차적 실질적 차원에서 모두 후퇴한 데는 언론의 책임이 크다. 비평의 기준을 '민주주의 유지와 성숙'에 둬야 할 이유는 미국과 유럽의 저널리즘 이론으로 뒷받침할 수 있다. 저널리즘의 목적은 사람들이 자유로워지고 스스로 다스리는 데에 필요한 정보를 제공하는 것이며, 공론장은 숙의 민주주의의 조건이다. 이 논문은 구체적 비평의 전략으로 세 가지를 제안했다. 첫째, 보수 진보의 프레임 탈피다. 진영 논리는 어떤 미디어의 보도와 논평이 민주주의 후퇴에 책임이 있는지 시시비비를 가리는 중요성을 희석시킬 수 있다. 둘째, 노사 관계에 대한 비평 확대다. 한국의 노사 관계는 언론 지형과 공론장 못지않게 크게 기울어져 있다. 저널리즘은 노사 관계 의제 설정에 인색했고, 보도와 논평을 하더라도 대부분 '자본 편향'이었다. 셋째, 주권자의 역량 강화다. 민주주의가 '민중에 의한 통치'라면, 가장 중요한 것은 민중의 역량 강화다.

• 한국병원경영학회지
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• 제18권3호
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• pp.1-26
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• 2013

To improve the competitiveness of the hospital provides high quality medical services in a hospital coordinator role is emphasized. This study on customer orientation of the role ambiguity in order to identify the impact of degree of customer orientation were analyzed for demographic differences. Dependent variable, customer orientation affects role ambiguity as independent variables, and regression analysis were set. And the control variables are set to support situational factors, customer orientation on the role ambiguity and hierarchical regression analysis was performed. Obtained through empirical results are as follows: First, according to the demographic characteristics of the hospital coordinator customer orientation, the difference between gender and medical subjects are not shown. Age, education, work experience, job title, and the hospital on the pattern of customer orientation has shown a difference. Second, according to the hospital coordinator role ambiguity about its impact on customer orientation analysis can be a role implementation, job implementation, opinion communication in achieving customer orientation was negatively affected. Third, role ambiguity, and customer orientation factors for the moderating effects of organizational support for the role of customer orientation can role implementation, job implementation, opinion communication was a statistically significant. Fourth, the role ambiguity factors and customer orientation for the administrative support for the moderating effect of customer orientation and role implementation is significant, but job implementation, opinion communication were statistically significant. Fifth, the role ambiguity factors and customer support for customer orientation and customer orientation for the moderating effects of role performance and the opinion communication was not statistically significant. However, job implementation was statistically significant. The limitations of this study are as follows: First, role ambiguity, situational factors and support due to limitations of the variable factors that may affect the customer orientation of a number of factors were excluded. So many exogenous variables in the measurement process can affect. Second, the variables measured as problems of self-assessment by the variable measuring the respondent's bias may occur. Third, This study is difficult to generalize. In other words, several areas of the province conducted by the empirical results of the survey as a limit on the overall generalization can follow.

• 한국보건간호학회지
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• 제34권2호
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• pp.263-276
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• 2020

Purpose: This paper systematically reviewed the effects of smoking cessation (SC) intervention among female smokers. Methods: A systematic search was performed targeting articles published on eight electronic databases, from January 1, 2010, to February 25, 2020. Nine studies were included in the systematic review. The risk of bias (RoB) tool was used to evaluate the quality of scientific evidence. Results: A randomized controlled trial (RCT) was performed in all nine studies. Interventions were classified as exercise (n=4), cognitive behavioral counseling (n=2), motivational counseling (n=1), group counseling with self-help group (n=1), and pharmacotherapy (n=1). The SC rates were measured using a 7-days point prevalence abstinence in 55.6% of the studies. Exercise studies showed higher SC rates in the experimental groups than control groups after the intervention, but the differences were not significant. Other interventions were employed in two or fewer studies or did not conduct long-term follow-up, thus we were unable to examine effects of these interventions. Conclusion: It is necessary to develop SC programs for female smokers by carefully considering the characteristics of female smokers. Further research will be needed to confirm the effects of SC programs in certain subgroups among females. Also more experimental studies on SC intervention should be carried out with scientific rigor.

• 대한전자공학회논문지TE
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• 제39권4호
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• pp.409-412
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• 2002

IMT-2000 전 대역(1920∼2170MHz, BW=250MHz)에서 사용되는 중계기용 2단 저잡음 증폭기를 설계하였다. Ansoft사의 Serenade를 이용하여 첫째 단 PHEMT의 소스와 접지간 source lead의 인덕턴스 값을 최적화하여 기판 선고로 등가화하고, 첫째 단의 잡음 정합은 물론 각 단의 정합회로가 간단하도록 high pass 구조로 설계하였다. 바이어스 회로는 단일 능동회로로 구성하였고, 인가전압은 8V, 총 전류는 180mA이다. 이때, 첫째 단 PHEMT의 Vgs = -0.4V, Vds = 4V이고, 둘째 단 AH1의 Vds = 5V이다. 상업화가 가능하도록 설계 기준을 정하여 제작되었고, 측정 결과 이득은 20dB, NF는 1dB, 입력 VSWR은 1.14∼l.3dB, P1dB는 22.4dBm, gain flatness는 ±0.45dB로 상업용 저잡음 증폭기로 사용될 수 있다.

• 기본간호학회지
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• 제25권2호
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• pp.120-133
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• 2018

Purpose: A meta-analysis was conducted to evaluate effectiveness of education programs using video recording and feedback in the improvement of competency in clinical skills for health care majors. Methods: Six databases were searched and inclusion criteria were randomized controlled trials (RCTs) or non-randomized controlled trials (NRTs) reporting level of skill competency using numerical measurements. Data analysis and synthesis were performed using Comprehensive Meta-Analysis software and Revman program. Results: Of 1,568 records, 11 studies met inclusion criteria. Statistically significant effectiveness of education programs using video recording and feedback was identified. A low risk of bias was detected among both RCTs and NRTs. Meta-analysis showed that the intervention groups had more effective improvements in skill competency (standardized mean difference [SMD]: 0.74; 95% CI: 0.33~1.16). Results of subgroup analysis showed higher effects when interventions dealt with one skill, used self-reflection with expert feedback, and included instruction from instructor in the education programs. Conclusion: Findings suggest that schools for health care majors should actively adopt video and feedback based skill training allowing educators to design effective programs. Potential is higher for students to achieve higher competency when they train with one skill at a time, use of instruction and receive feedback from experts.

• 한국초등과학교육학회지:초등과학교육
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• 제39권4호
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• pp.506-521
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• 2020

This study aims to develop a scientific creativity task which science-gifted elementary students can conduct on a field trip to a botanical garden, and to analyze the results from conducting the task. For this, 38 science-gifted fifth-graders from the Science-Gifted Education Center, located at the Office of Education, participated in a field trip to a botanical garden, as a part of their program. Prior to the program, researchers developed a scientific creativity task for outdoor education program, along with science education specialists and teachers. The tasks were to observe plants, and to create something new and useful, or, in other words, scientifically creative, based on the plants' characteristics. The students could submit at most three ideas. Also, they assessed their own ideas, and selected an idea that they thought was the most creative. The results were analyzed by using the scientific creativity formula. The main findings from this study are as follows. First, it was found that the scientific creativity formula had an upward bias in assessing originality. Second, the students tended to assess the usefulness of their own ideas more generously. Third, the correlation between self-assessment results and scores from the scientific creativity formula for originality was r=.43. Fourth, in formula-based assessments, the correlation between originality scores and usefulness scores was relatively high, at r=.56. Fifth, the correlation between a student's scientific creativity score and the number of his or her ideas was very low, at r=.23. Sixth, when the ideas chosen as the most creative by students were compared with the ideas that had the highest scores in formula-based assessments, it was shown that 8 out of 19 students (42.1%) did not choose the idea that appeared to be the most creative when graded by the formula. This study is concluded by discussing the lessons from the scientific creativity task analysis for primary science education and gifted education.