• 한국대기환경학회지
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• 제15권3호
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• pp.305-315
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• 1999

The annular denuder system(ADS) was used to determine characteristics of acidic air pollutants and $PM_{2.5}$ species in Seoul-metropolitan areas. All measurements were done simultaneously in downtown(Kwanghwamun, Mullae, Chamshil, Ssangmun dongs) and outskirts(Puch n, Kuri cities) during four seasons. The samples were analyzed using ion chromatography for gas-phase matters(HCl, $HNO_2$, $HNO_3$ and $SO^2$) and particulate phase matters($Cl^-$, $NO^{2-}$, $NO_3^-$, $SO_4^{2-}$, $Na^+$, $NH_4^-$ and $Ca^{2+}$) and was measured fine particles($PM_{2.5}$). The seasonal mean concentrations of HCl, HNO2, HNO3 and SO2 in downtown and outskirt areas were very similar. All chemical species monitored from this study showed seasonal variations. Nitric acid(HNO3) and Nitrous acid(HNO2) were showed higher concentrations during the summer. $PM_{2.5}$, $SO_4^{2-}$, $NH_4^-$, $NO_3^-$ and $Cl^-$ in the particulate phase matters were higher levels during the winter months. The concentrations of these components were 54.8, 3.82, 2.49, 1.80 and 1.02$\mu\textrm{g}$/㎥, respectively.

• 생명과학회지
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• 제27권5호
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• pp.536-544
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• 2017

미선나무 미성숙 종자는 물푸레나무과의 관목으로 전세계적으로 1속 1종의 중요한 식물자원이다. 대한민국에서는 미선나무 자생지를 보존하고 멸종위기식물로 보호하고 있다. 이러한 이유로 미선나무 미성숙 종자에 대한 연구는 미비하다. 본 연구에서 미선나무 미성숙 종자의 항산화 활성과 미백 관련 단백질인 tyrosinase, TRP-1, TRP-2, MITF의 단백질 발현 및 mRNA 수준의 발현 억제 활성을 확인하였다. 미선나무 미성숙 종자는 활성산소종에 효과가 뛰어났으며, 활성산소종은 노화, 염증, 암 등 다양한 질병을 야기시킨다. 항산화 활성은 DPPH, ABTS 라디칼 소거활성 및 환원력을 평가하였으며, 이러한 활성은 페놀류 화합물과 관계가 있는 것으로 알려져 있다. 페놀류 화합물은 천연 폴리페놀이라고 불리는 파이토케미칼로서 다양한 환경적 요인에 의한 식물 방어 기작의 일환으로 생성되는 2차 대사산물이다. 페놀류 화합물은 노화, 항암을 포함한 많은 인간의 건강에 긍정적인 영향을 준다고 알려져 있다. 미선나무 미성숙 종자는 tyrosinase, TRP-1, TRP-2 단백질 및 mRNA를 조절하였으며, 이러한 요인은 멜라닌 생합성에 중요한 역할을 한다. 또한 microphthalmia-associated transcription factor (MITF)의 단백질 및 mRNA를 억제하였다. MITF는 Tyrosinase, TRP-1, TRP-2의 발현과 전사에 연관된 인자로 알려져 있다. 미선나무 미성숙 종자의 미백활성, 페놀류 화합물, 항산화 활성 사이의 연관관계를 확인하였으며, 결론적으로 미선나무 미성숙 종자는 천연 식물 자원으로부터 얻을 수 있는 항산화제 및 피부 미백을 위한 기능성 화장품 원료로 사용될 수 있다.

• 중환자간호학회지
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• 제13권1호
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• pp.1-14
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• 2020

Purpose : The purpose of this study was to identify the factors influencing the general hospital nurses' confidence about the advance directives (ADs). Methods : This is a descriptive cross-sectional study. A total of 105 nurses were asked questions about characteristics, knowledge, attitude, learning needs, and confidence the about ADs, using structured questionnaires. Data were analyzed by descriptive statistics, t-test, ANOVA, Pearson's correlation coefficient, and multiple regression. Results : The mean scores of knowledge were 7.26±1.47; attitude, 2.80±0.31; learning needs, 4.22±0.62; and confidence, 2.57±0.74. It was observed that knowledge had significant correlations with attitude (r=.43, p<.001), learning needs (r=.29, p=.003), and confidence (r=.40, p<.001), and attitude had significant correlations with learning needs (r=.31, p=.001) and confidence (r=.45, p<.001). Using multiple regression analysis, it was found that confidence was significantly influenced by knowledge (β=.27, p=.007), attitude (β=.21, p=.043), and experience of nursing or counseling a patient who wrote ADs (β=-.19, p=.046). The explanatory power of this model was 37.9% (F=5.16, p<.001, R²=.379). Conclusions : These findings suggest the need to develop a program to enhance nurses' knowledge, positive attitude, and experience of nursing or counseling a patient who wrote ADs.

• International Journal of Human Ecology
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• 제7권2호
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• pp.29-41
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• 2006

Various current events provide evidence that society is undergoing changes in perceptions of social relationships. Specifically, visual media in the form of advertisements can convey images which reflect society's values and concepts about role relationships. The purpose of this research was to examine ads in fashion magazines to determine what types of model roles and role relationships typically appear in fashion advertising which can mirror society's values. A content analysis was conducted of ads obtained from US Vogue and US GQ for the year 2002. Six kinds of roles/relationships were found: (1) Narcissism (representing self absorption), (2) sexually enticing opposite-sex relationships, (3) close/romantic same-sex relationships, (4) friend relationships, (5) family relationships, and (6) independent relationships. Of these, narcissism predominated, however, a small number of sexually provocative ads appeared as well as same-sex romantic relationships. Because sole (single) models were more typical, they also were examined to determine ways in which they relate to the audience. Characteristics examined included body presentation & pose, eye gaze, and facial expression. Direct eye gaze was the typical way to engage the audience. Gender differences were apparent: smiling was more typical of women, indifference for men. The symbolic meaning and values investigated from this research are the blurring of gender identity portrayed in homosexual imagery, family values, and the value of youth. The consistency of models' race in ads does not portray the diversity reflected in the demographic census.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• 제25권1호
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• pp.28-36
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• 2014

Objectives : The goal of this study was to examine the association between zinc and lead level and symptoms of attention-deficit hyperactivity disorder (ADHD) among Korean children. Methods : A total of 89 clinic-referred children participated in the study (ADHD group=45, control group=44). The participants were 5-15 years old, and were mainly from urban areas of Seoul, Korea. ADHD was diagnosed using the Kiddie-Schedule for Affective Disorders and Schizophrenia-Present and Lifetime Version. We excluded children with a comorbid psychiatric disorder, medical illness requiring medication, or a prior history of taking ADHD medication. In order to evaluate the severity of ADHD symptoms, parents' Korean ADHD Rating Scale (K-ARS) was used. The ADHD diagnostic system (ADS) was used for evaluation of the severity of inattention and impulsivity. All participants completed the intelligence test and hair mineral analysis. Multiple regression analysis was used to examine the effect of hair zinc and lead levels on the K-ARS and ADS. We measured the predictive ability of the zinc and lead levels using logistic regression analysis. Results : The lead level explained the score for omission errors, commission errors, and response time SD in visual ADS in the ADHD group (adjusted $R^2$=.243, p<.01, adjusted $R^2$=.362, p<.01, and adjusted $R^2$=.275, p<.01), the score for omission errors of auditory ADS in ADHD group (adjusted $R^2$=.407, p<.01) and the entire group (adjusted $R^2$=.292, p<.01). Zinc was significantly explanatory for the K-ARS scores for the entire group (adjusted $R^2$=.248, p<.001) and the ADHD group (adjusted $R^2$=.247, p<.05). Conclusion : These findings suggest a possible role of zinc and lead in ADHD. Lead concentration in hair samples affected the ADS scores, and this was more prominent in children with ADHD. Children with ADHD had a lower zinc concentration in their hair, and the zinc concentration in hair showed negative correlation with the K-ARS score.

• 한국산학기술학회논문지
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• 제13권5호
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• pp.2319-2324
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• 2012

본 논문에서는 가유전체 기판구조를 이용한 비대칭 브랜치 라인 커플러의 설계에 대하여 기술한다. 가유전체 기판구조에서는 주기적으로 다수의 비어홀들이 삽입되므로 등가적으로 유효유전율과 유효투자율이 증가하여, 여기에 전송선로를 구현할 경우 표준형 선로에 비하여 동일한 전기적 길이일 때 물리적 길이와 선폭이 감소하게 된다. 이런 특성을 이용하여 초고주파 회로들을 소형화하여 설계할 수 있는데, 본 논문에서는 2GHz대에서 동작하는 3:1 비대칭 브랜치 라인 커플러를 소형화하여 설계하는 것에 대하여 기술한다. 설계된 커플러는 표준형 전송선로를 이용하여 설계한 회로에 비하여 동일한 성능을 가지면서 약 53.4%의 크기를 갖는다. 비대칭 전력 분배 비율이 시뮬레이션과 측정 데이터에서 잘 일치하고 있으며, 측정된 손실도 불과 0.2dB 이내로 매우 적다.

• 한국대기환경학회지
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• 제18권4호
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• pp.297-303
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• 2002

Fine particles (d$_{p}$ < 2.5 $\mu$m) were measured using an annular denuder system (ADS) in Chongju. The data set was collected on fifty-eight different days with a 24-hr sampling period from October 27, 1995 through August 25, 1996. Particulate nitrate in the ADS was also measured on teflon and nylon filters in series behind denuders to collect HNO$_3$, HNO$_2$, SO$_2$and NH$_3$. From this study. the mean concentration of particulate nitrate of PM$_{2.5}$ in the ADS were seen with the following order: winter (5.05) ＞fall (4.36) ＞spring (3.92) > summer (1.10 $\mu\textrm{g}$/㎥). Nitrate losses, which calculated from the ratio of nylon filter nitrate to the sum of teflon and nylon filter nitrates, varied in the following manner summer (72.2%) > spring (42.6%) > fall (23.5%)> winter (0.4%). Especially, gaseous nitric acid was dominant at temperature higher than 8$^{\circ}C$ while particulate nitrate was major species in total nitrate below that temperature. This indicates the particulate nitrate loss is strongly correlated rather with ambient temperature.e.e.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 추계학술대회 논문집 전기물성,응용부문
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• pp.229-232
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• 2003

AC PDP의 ADS 추동 방식은 구동 방법이 간단하여 구현하기가 용이할 뿐만 아니라 가장 안정적인 구동 방식으로 널리 사용되고 있다 [1]. 그러나 ADS 구동 방식은 주사선의 수가 늘어남에 따라 어드레싱에 필요한 시간이 증가하게 되고 유지방전 구간에 할애할 시간이 상대적으로 감소하게 되어 휘도가 저하되게 되는 문제점을 갖고 있다. 이러한 문제를 해결하기 위하여 어드레싱 시간을 최소화하기 위한 고속 어드레싱 기술에 대한 연구가 계속하여 진행되고 있다 [2-10]. 본 논문에서는 고속 구동 시에 나타나는 불안정한 어드레싱으로 인한 화질의 저하문제를 해결하기 위한 개선된 ADS 구동파형을 제시한다. 초기화 구간의 Reset 파형은 어드레싱 추간의 특성에 중요한 영향을 미치게 되는데, Reset 구간에서 생성된 벽전하를 어드레싱 방전구간 동안 지속적으로 유지되게 함으로서 어드레싱 방전전압을 줄이고 안정적인 어드레싱이 유지될 수 있도록 하였다. 본 논문에서는 Priming Effect의 영향이 급격히 감소하는 80us 이후, 벽전하의 생성을 돕는 Wall Charge Acceleration Pulse를 적용함으로서 불안정한 어드레싱 문제를 해결할 수 있는 방법을 제시하였고 휘도의 불균등화로 인한 화질 저하의 문제를 해결하였다.

• 조명전기설비학회논문지
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• 제19권4호
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• pp.39-46
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• 2005

본 연구는 3 전극 교류구동형 PDP의 ADS구동방식에 관한 것으로 휘도의 저감이 없는 안정적인 표시방전이 가능한 최소의 어드레스와 표시방전 유지펄스의 폭을 도출하는 것이다. 실험결과로부터 어드레스 펄스폭이 $1.5[{\mu}s]$이 상만 되면 효과적인 어드레스 방전이 가능하였고 35[V] 어드레스 동작마진을 얻을 수 있었다. 또한, 표시방전 유지펄스의 폭이 $2[{\mu}s]$이상 되면 25[V]의 동작마진을 가지고 안정적인 표시방전의 유지가 가능하였다. 이 조건들을 수평 주사선수 1080라인의 Full-HDTV급 PDP에 적용할 경우 8개의 서브필드와 총 1420개의 표시방전 유지펄스를 사용할 수 있다.

• Journal of Information Science Theory and Practice
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• 제5권4호
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• pp.6-25
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• 2017

In this paper, a large-scale study on users' understanding of search-based advertising is presented. It is based on (1) a survey, (2) a task-based user study, and (3) an online experiment. Data were collected from 1,000 users representative of the German online population. Findings show that users generally lack an understanding of Google's business model and the workings of search-based advertising. 42% of users self-report that they either do not know that it is possible to pay Google for preferred listings for one's company on the SERPs or do not know how to distinguish between organic results and ads. In the task-based user study, we found that only 1.3 percent of participants were able to mark all areas correctly. 9.6 percent had all their identifications correct but did not mark all results they were required to mark. For none of the screenshots given were more than 35% of users able to mark all areas correctly. In the experiment, we found that users who are not able to distinguish between the two results types choose ads around twice as often as users who can recognize the ads. The implications are that models of search engine advertising and of information seeking need to be amended, and that there is a severe need for regulating search-based advertising.