• 제목/요약/키워드: higher order panel method

검색결과 66건 처리시간 0.032초

Vertical Distribution and Potential Risk of Particulate Polycyclic Aromatic Hydrocarbons in High Buildings of Bangkok, Thailand

  • Pongpiachan, Siwatt
    • Asian Pacific Journal of Cancer Prevention
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    • 제14권3호
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    • pp.1865-1877
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    • 2013
  • Vertical variations of polycyclic aromatic hydrocarbon (PAH) concentrations in $PM_{10}$ were investigated in order to assess the factors controlling their behavior in the urban atmosphere of Bangkok City, Thailand. Air samples were collected every three hours for three days at three different levels at Bai-Yok Suit Hotel (site-1 and site-2) and Bai-Yok Sky Hotel (site-3) in February $18^{th}-21^{st}$, 2008. The B[a]P concentration showed a value 0.54 fold, lower than the United Kingdom Expert Panel on Air Quality Standard (UK-EPAQS; i.e. 250 pg $m^{-3}$) at the top level. In contrast, the B[a]P concentrations exhibited, at the ground and middle level, values 1.50 and 1.43 times higher than the UK-EPAQS standard respectively. PAHs displayed a diurnal variation with maximums at night time because of the traffic rush hour coupled with lower nocturnal mixing layer, and the decreased wind speed, which consequently stabilized nocturnal boundary layer and thus enhanced the PAH contents around midnight. By applying Nielsen's technique, the estimated traffic contributions at Site-3 were higher than those of Site-1: about 10% and 22% for Method 1 and Method 2 respectively. These results reflect the more complicated emission sources of PAHs at ground level in comparison with those of higher altitudes. The average values of incremental individual lifetime cancer risk (ILCR) for all sampling sites fell within the range of $10^{-7}-10^{-6}$, being close to the acceptable risk level ($10^{-6}$) but much lower than the priority risk level ($10^{-4}$).

The Effects of Mobile phone Dependence and Fandom Activities on the Satisfaction of life of Adolescents : Mediating Effect of Self-Resilience

  • Bang, Sung-A
    • 한국컴퓨터정보학회논문지
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    • 제24권11호
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    • pp.255-262
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    • 2019
  • 본 연구는 청소년의 삶의 만족도에 영향을 주는 요인을 살펴보고자 한국 아동 청소년 패널조사(KCYS)의 중1 패널데이터를 대상으로 분석하였다. 이를 바탕으로 청소년들의 삶의 만족도를 높이기 위한 올바른 휴대폰 사용과 팬덤활동에 관한 실천적 정책적 방안을 제언하는 것을 목적으로 한다. 본 연구의 분석방법으로 AMOS 23.0을 활용하였으며, 연구결과, 첫째, 청소년의 삶의 만족도가 높을수록 휴대폰 의존도가 낮은 것으로 나타났다. 둘째, 청소년의 휴대폰 의존도는 자아탄력성에 의해 삶의 만족도에 유의한 영향을 미치는 것으로 나타났다. 결론적으로 청소년들의 삶의 만족도를 향상시키기 위해서는 사회정서발달 및 급변하는 문화 활동에 맞는 맞춤형 프로그램이 개발 보급되어야 할 것 임을 시사하고 있다.

고전압 태양광 패널용 고효율 단상 태양광 인버터 (A High-efficiency Single-phase Photovoltaic Inverter for High-voltage Photovoltaic Panels)

  • 류형민
    • 전기전자학회논문지
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    • 제26권4호
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    • pp.584-589
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    • 2022
  • 고전압 태양광 패널에서 단상 계통으로의 직류-교류 전력 변환을 위해 벅부스트 컨버터에 풀브리지 인버터를 종속적으로 연결하는 두 단계의 무변압기 인버터가 주로 사용된다. 태양광 패널의 큰 기생 커패시턴스에 기인하는 과도한 누설 전류를 피하기 위해 풀브리지 인버터는 단극성 PWM에 비해 훨씬 더 많은 전력 손실을 초래하는 양극성 PWM으로만 스위칭할 수 있다. 그런 낮은 효율을 개선하기 위해 본 논문은 벅부스트 컨버터에 회로 절연을 위한 IGBT와 다이오드를 하나씩 추가한 새로운 토폴로지를 제안한다. 제안된 회로 절연 방식은 누설 전류를 증가시키지 않으면서 풀브리지 인버터에서 단극성 PWM을 가능케 함으로써 전체 효율을 개선한다. 제안된 방법의 타당성은 컴퓨터 시뮬레이션과 전력 손실 계산을 통해 검증한다.

노인의 사회자본과 건강위해 행위 및 건강수준이 의료서비스 이용에 미치는 영향 (The effect of social capital, health risk behavior and health status on medical care utilization by the elderly)

  • 우경숙;서제희;김계수;신영전
    • 보건행정학회지
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    • 제22권4호
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    • pp.497-521
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    • 2012
  • Objectives This study aimed to investigate the effect of social capital, health risk behavior and health status on medical care utilization by the elderly. The data and Research method Data were obtained from the 4th wave survey of the Korea Welfare Panel Study. 4,087 household members aged 65 years and over were subject to analysis. Descriptive statistics are used to describe the basic features of the data in a study. we performed a structural equation modeling(SEM) analysis to evaluate the effect of social capital and mediating effect of health risk behavior and health status. Results Results showed that factors related to medical care utilization of the elderly were different depending on types of service (inpatient and outpatient service) except health status. Age, higher social capital, more health-risk behavior and poorer health status were associated with increased use of inpatient service. Social capital was found to have a positive direct effect on it. Also, social capital had an indirect effect on reducing use of inpatient services by improving health status. On the other hand, lower age and higher household income tended to increase use of outpatient service, while higher social capital and higher health status were inversely related. Social capital had a direct effect and an indirect effect on reducing use of outpatient service and, at that time, health status played a mediating role. Conclusions Social capital may contribute to improve health status and indirectly reduce medical care utilization of the elderly by enhancing their health status. These results provide evidence that more policy and strategy considerations should be needed for the elderly to strengthen their social capital in order to enhance their levels of health and more efficient utilization of medical care.

Zn$_2$SiO$_4$:Mn 녹색형광체의 입도제어 및 발광특성 (Control of Particle Size and Luminescence Property in Zn$_2$SiO$_4$:Mn Green Phosphor)

  • 성부용;정하균;박희동
    • 한국재료학회지
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    • 제11권8호
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    • pp.636-640
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    • 2001
  • PDP용 녹색 형광체의 발광특성을 개선시키기 위해 고안된 액상의 화학적 합성법을 사용하여 조성식이 $Zn_{2-x}$ $SiO_4$:xMn(x=0.05, 0.08)인 형광체를 입자크기가 0.5~2$\mu\textrm{m}$로 조절하여 제조하였다. 제조된 형광체 입자는 구상이며 잘 분산된 형상을 봉주었고, 고상반응법에 비해 상대적으로 낮은 $1080^{\circ}C$에서 willemite구조의 단일상을 얻을 수 있었다. 또한 진공 자외선 영역의 147 nm의 여기원을 사용하여 광발광 특성을 조사하였다. 입자의 크기가 1$\mu\textrm{m}$이고 Mn의 도핑양이 8mole%일 때, 상용 형광체와 비교하여 발광세기는 약 40% 향상되었고 색좌표는 x=0.24, y=0.69로 거의 일치하는 결과를 얻을 수 있었다. 측정된 형광체의 잔광시간은 7.8ms이었다.

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Zn$_2$SiO$_4$:Mn 녹색형광체의 입도제어 및 발광특성 (Control of Particle Size and Luminescence Property in Zn$_2$SiO$_4$:Mn Green Phosphor)

  • 성부용;정하균;박희동
    • 한국재료학회지
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    • 제11권8호
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    • pp.363-363
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    • 2001
  • PDP용 녹색 형광체의 발광특성을 개선시키기 위해 고안된 액상의 화학적 합성법을 사용하여 조성식이 $Zn_{2-x}$ $SiO_4$:xMn(x=0.05, 0.08)인 형광체를 입자크기가 0.5~2$\mu\textrm{m}$로 조절하여 제조하였다. 제조된 형광체 입자는 구상이며 잘 분산된 형상을 봉주었고, 고상반응법에 비해 상대적으로 낮은 $1080^{\circ}C$에서 willemite구조의 단일상을 얻을 수 있었다. 또한 진공 자외선 영역의 147 nm의 여기원을 사용하여 광발광 특성을 조사하였다. 입자의 크기가 1$\mu\textrm{m}$이고 Mn의 도핑양이 8mole%일 때, 상용 형광체와 비교하여 발광세기는 약 40% 향상되었고 색좌표는 x=0.24, y=0.69로 거의 일치하는 결과를 얻을 수 있었다. 측정된 형광체의 잔광시간은 7.8ms이었다.

Development of Large-area Plasma Sources for Solar Cell and Display Panel Device Manufacturing

  • 서상훈;이윤성;장홍영
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2011년도 제41회 하계 정기 학술대회 초록집
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    • pp.148-148
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    • 2011
  • Recently, there have been many research activities to develop the large-area plasma source, which is able to generate the high-density plasma with relatively good uniformity, for the plasma processing in the thin-film solar cell and display panel industries. The large-area CCP sources have been applied to the PECVD process as well as the etching. Especially, the PECVD processes for the depositions of various films such as a-Si:H, ${\mu}c$-Si:H, Si3N4, and SiO2 take a significant portion of processes. In order to achieve higher deposition rate (DR), good uniformity in large-area reactor, and good film quality (low defect density, high film strength, etc.), the application of VHF (>40 MHz) CCP is indispensible. However, the electromagnetic wave effect in the VHF CCP becomes an issue to resolve for the achievement of good uniformity of plasma and film. Here, we propose a new electrode as part of a method to resolve the standing wave effect in the large-area VHF CCP. The electrode is split up a series of strip-type electrodes and the strip-type electrodes and the ground ones are arranged by turns. The standing wave effect in the longitudinal direction of the strip-type electrode is reduced by using the multi-feeding method of VHF power and the uniformity in the transverse direction of the electrodes is achieved by controlling the gas flow and the gap length between the powered electrodes and the substrate. Also, we provide the process results for the growths of the a-Si:H and the ${\mu}c$-Si:H films. The high DR (2.4 nm/s for a-Si:H film and 1.5 nm/s for the ${\mu}c$-Si:H film), the controllable crystallinity (~70%) for the ${\mu}c$-Si:H film, and the relatively good uniformity (1% for a-Si:H film and 7% for the ${\mu}c$-Si:H film) can be obtained at the high frequency of 40 MHz in the large-area discharge (280 mm${\times}$540 mm). Finally, we will discuss the issues in expanding the multi-electrode to the 8G class large-area plasma processing (2.2 m${\times}$2.4 m) and in improving the process efficiency.

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기업가형 대학(Entrepreneurial University)을 위한 대학의 창업 성과 영향요인 분석 (Analysis of Factors Influencing Entrepreneurial Performance at the University Level for Becoming Entrepreneurial Universities)

  • 임한려;홍성표
    • 벤처창업연구
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    • 제15권2호
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    • pp.19-32
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    • 2020
  • 이 연구는 기업가형 대학에 대한 관심이 높아지는 상황에서 대학생과 전임교원의 창업 성과를 중심으로 대학 차원의 영향 요인을 구명하는데 목적이 있었다. 연구목적을 달성하기 위하여 2015년부터 2018년까지 대학알리미 공시자료를 바탕으로 최소 2개년도 대학생 및 전임 교원 창업자 수에 대한 자료가 확보되어 있는 대학을 대상으로 패널을 구축하였다. 이를 통해 154개 대학의 4개년도 자료를 분석에 활용하였다. 분석 방법으로는 대학의 특성을 확인하기 위해 빈도분석과 기술통계를 실시하였으며, 이후 자료의 종단적 성격과 분포를 고려하여 패널 음이항 회귀분석을 실시하였다. 또한 Hausman test를 통해 확률효과를 중심으로 결과를 해석하였다. 연구를 통해 도출된 결과는 다음과 같다. 첫째, 2015년부터 2018년까지 국내 대학의 창업성과와 변화 추이에 대한 분석 결과, 최근 4년간 대학의 창업 성과는 꾸준히 증가하고 있는 것으로 나타났으며, 상대적으로 대학생 창업자 수의 증가폭이 더 높았다. 둘째, 대학생의 창업을 촉진하기 위해서 경제적, 교육적 접근이 병행될 필요가 있다. 대학생의 창업을 촉진하는 대학 차원의 요인은 학생 1인당 장학금, 창업 지원금, 창업 강의, 창업 동아리인 것으로 확인되었다. 셋째, 학교의 개방성 및 지역적 특성이 대학생의 창업을 촉진할 수 있다. 넷째, 전임교원에 대한 연구 환경 조성 및 창업 지원이 이들의 창업 성과를 높일 수 있다. 전임교원의 창업을 촉진하는 대학 차원의 요인은 전임 교원 1인당 연구비, 창업 지원인력 인 것으로 나타났다. 이러한 연구 결과를 바탕으로 도출된 결론의 다음과 같다. 첫째, 기업가형 대학으로 발전하기 위한 국내 대학 전반의 노력이 요구된다. 둘째, 기업가형 대학으로 변화하기 위해 창업에 대한 직접적인 지원이 필요하다. 셋째, 기업가형 대학으로서, 지역, 규모에 따른 대학별 격차를 해소할 수 있는 방안을 모색해야 한다. 넷째, 대학의 연구 성과를 창업으로 연계할 수 있는 지원을 강화할 필요가 있다. 다섯째, 전임교원의 창업에 대한 분위기 마련이 필요하다.

종합병원 간호사가 인식하는 환자교육 중요도와 수행도의 관계연구 (A Study on the Perception of the Importance and Performance of Patient Education of the Clinical Nurses)

  • 유은경;서문자
    • 한국간호교육학회지
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    • 제6권2호
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    • pp.287-302
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    • 2000
  • The purpose of the study are to examine the perception of the importance and performance of patient education of the clinical nurse and find out the interfering factors in practicing patient education. The data were collected from convenient sample of 256 clinical nurses working in the nursing units of adult patients except the psychiatric unit, obstetric unit, dental surgical unit and intensive care unit of one University Hospital in Seoul from September 29 to October 2, 1998. Three measurement tools of self-report- questionnaires developed by researcher used. For the content validity of the questionnaires, two sessions of panel discussion and a pilot test were done and finally factor analysis was done with Varimax method. Analysis of data was done with SAS program using frequency, percentage, means, standard deviation, Pearson's Correlation Coefficients, t-test and ANOVA. The obtained results were as follows : 1. The surveyed nurses perceived the importance of patient education at higher level with mean score of 4.08 among 5 point than their perception of practice( mean score : 3.42). 2. There was positive significant correlation(r=.29, p=0.0001)between nurses' perception of the importance of patient education and it's practice 3. Among the teaching contents for patients, 'information of diagnostic procedure and operation' and 'orientation of hospitalization' were perceived most important. And 'preparation for discharge' and 'understanding of disease and health promotion' were perceived least important 4. Among the teaching contents for patients, 'orientation of hospitalization' and 'information of diagnostic procedure and operation' were perceived highly performable. And 'understanding of disease and health promotion' and 'preparation for discharge' were perceived least performable. 5. Three types of interfering factors were identified as patient-factor, situational factor, nurse-factor. The mean degree of impediment with the interfering factors was at average level(3.09 among 5). The patient and situational factors of impediments were more interfering than nurse- factor for teaching patients. 6. In older age(p<.05), married state (p<.05), higher educational status (p<.01), higher clinical experience (p<.01) and higher position(p<.01), the score of perceived importance of patients education was more high. 7. In older age(p<.01), higher clinical experience(p<.001) and surgical unit (p<.01), the score of perceived performance of patients education was more high. In conclusion, in order to activate patient education practice in the clinical setting, the continuing education for patients education should be more emphasized and the effective teaching methods and materials should be developed to help patient teaching. And an organizational support such as budgeting for patient education and reimbursement system should be administrated.

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제주 향토음식을 활용한 음식관광상품 개발 및 CVM을 적용한 경제적 가치 평가 (Development of Jeju Local Food Tour Package and Economic Value Estimation based on Contingent Valuation Method)

  • 안소정;윤지영
    • 동아시아식생활학회지
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    • 제26권4호
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    • pp.346-358
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    • 2016
  • Local food reflects the identity and image of a specific region. It is also a core element for determining tourists' experience of a region. The purpose of the present study was to develop a Jeju food tour package using local foods and estimate the economic value of the suggested tour package using Contingent Valuation Method (CVM). Five food tour packages were developed by researchers. In order to modify and measure the value of each package, an expert panel survey was conducted, and 'package 5' was selected as a food tour scenario for the tourist survey. A survey was conducted on 295 domestic tourists who visited Jeju within the past 10 years in order to evaluate the economic value and feasibility of the Jeju food tour package. A total fo 72.9% of respondents answered that they were willing to pay for the Jeju local food tour, and the willingness to pay (WTP) range was between ₩45,000 and ₩105,000. The primary factors correlated with WTP was food expenses, followed by leisure experience expenses, interest in local foods, education level, visit frequency and age. The WTP of the Jeju local food tour was calculated with the significantly affected factors using stepwise regression model. The result of the present study reveal that tourists' WTP increased with higher food expenses, education level, and age group. The average value of food expenses, education level, and age were substituted into the formula derived from the regression analysis, yielding 58,385.752 KRW as the WTP. The expected economic value created by exploiting the Jeju local food tour was shown to be 700 billion KRW per year, calculated by multiplying WTP of the food tour packages by the number of tourists. This study examined the feasibility and plan of the food tour package to increase the economic value of Jeju local food. In the case of the culinary tour program based on Jeju local food launching, the estimated economic effect was great. Therefore, in-depth research to merchandise the Jeju local food tour program is needed.