• Title/Summary/Keyword: higher-order panel method

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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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    • v.14 no.3
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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
    • Journal of the Korea Society of Computer and Information
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    • v.24 no.11
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    • pp.255-262
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    • 2019
  • The purpose of this study to the factors affecting the satisfaction of adolescent life. This study analyzed data from the panel data of the Korean Children and Youth Panel Survey (KCYS). Based on this, it aims to propose practical and policy measures for the correct use of mobile phones and fandom activities to increase the satisfaction of young people's lives. The AMOS 24.0 was used as an analytical method of this study. First, the higher the life satisfaction of adolescents, the lower the dependence on mobile phones. Second, the mobile phone dependence of adolescents has a significant effect on life satisfaction by Self-resilience. In conclusion, it is suggested that customized programs suitable for social emotional development and rapidly changing cultural activities should be developed and distributed in order to improve the life satisfaction of adolescent.

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

  • Hyung-Min, Ryu
    • Journal of IKEEE
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    • v.26 no.4
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    • pp.584-589
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    • 2022
  • For DC-AC power conversion from a high-voltage photovoltaic panel to a single-phase grid, the two-stage transformerless inverter with a buck-boost converter followed by a full-bridge inverter is widely used. To avoid an excessive leakage current due to the large parasitic capacitance of the photovoltaic panel, the full-bridge inverter can only adopt the bipolar PWM which results in much higher power loss compared to the unipolar PWM. In order to overcome such a poor efficiency, this paper proposes a new topology in which an IGBT and a diode for circuit isolation are added to the buck-boost converter. The proposed circuit isolation method allows the unipolar PWM in the full-bridge inverter without any increase in the leakage current so that the overall efficiency can be improved. The validity of the proposed solution is verified by computer simulation and power loss calculation.

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

  • Woo, Kyung-Sook;Seo, Jae-Hee;Kim, Gye-Soo;Shin, Young-Jeon
    • Health Policy and Management
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    • v.22 no.4
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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.

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

  • Seong, Bu-Yong;Jeong, Ha-Gyun;Park, Hui-Dong
    • Korean Journal of Materials Research
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    • v.11 no.8
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    • pp.636-640
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    • 2001
  • In order to improve the optical Performance of green emitting phosphor for plasma display panel (PDP) application, the wet chemical method for preparing $Zn_{2-x}$ $SiO_4$:xMn (xi=0.02. 0.08) phosphor was designed. The spherical phosphor particles were obtained and the size can be between 0.5$\mu\textrm{m}$ and 2$\mu\textrm{m}$. The formation of phosphor, which had the willemite structure, was completed at relatively low temperature of 108$0^{\circ}C$. Also, photoluminescence Properties of the phosphors prepared were investigated under vacuum ultraviolet excitation. In particular, the emission intensity of Zn$_2$SiO$_4$:0.08Mn phosphor having the 1$\mu\textrm{m}$ of particle size was higher than that of commercial phosphor by 40%. The decay time of zinc silicate powder prepared as containing 8 mole% of manganese has been measured as 7.8ms.

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

  • 성부용;정하균;박희동
    • Korean Journal of Materials Research
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    • v.11 no.8
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    • pp.363-363
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    • 2001
  • In order to improve the optical Performance of green emitting phosphor for plasma display panel (PDP) application, the wet chemical method for preparing $Zn_{2-x}$ $SiO_4$:xMn (xi=0.02. 0.08) phosphor was designed. The spherical phosphor particles were obtained and the size can be between 0.5$\mu\textrm{m}$ and 2$\mu\textrm{m}$. The formation of phosphor, which had the willemite structure, was completed at relatively low temperature of 108$0^{\circ}C$. Also, photoluminescence Properties of the phosphors prepared were investigated under vacuum ultraviolet excitation. In particular, the emission intensity of Zn$_2$SiO$_4$:0.08Mn phosphor having the 1$\mu\textrm{m}$ of particle size was higher than that of commercial phosphor by 40%. The decay time of zinc silicate powder prepared as containing 8 mole% of manganese has been measured as 7.8ms.

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

  • Seo, Sang-Hun;Lee, Yun-Seong;Jang, Hong-Yeong
    • Proceedings of the Korean Vacuum Society Conference
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    • 2011.08a
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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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Analysis of Factors Influencing Entrepreneurial Performance at the University Level for Becoming Entrepreneurial Universities (기업가형 대학(Entrepreneurial University)을 위한 대학의 창업 성과 영향요인 분석)

  • Lim, Hanryeo;Hon, Sungpyo
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.15 no.2
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    • pp.19-32
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    • 2020
  • The purpose of this study was to investigate the influence factors of the university level centering on the entrepreneurial performance of the university students and full-time faculties in the situation of increasing interest in entrepreneurial university. In order to achieve the purpose of the study, a panel data was established from 2015 to 2018 on the basis of the university notification data. The panel data included universities with data on the number of university students and full-time faculty founders for at least two years. Through this, four year data from 154 universities were used for analysis. As an analysis method, frequency analysis and descriptive statistics were conducted to understand the characteristics of the university. Since then, panel negative binomial regression analysis has been conducted in consideration of the longitudinal features and distribution of the data. Also, based on the Hausman test results, the results were interpreted based on random effect model. The results of this study are as follows. First, as a result of the analysis of the entrepreneurial performance and the change trend of the domestic university from 2015 to 2018, the entrepreneurial performance of the university has been steadily increasing in the last four years, and the increase in the number of university student entrepreneurs was relatively higher than the full-time faculties. Second, economic and educational approaches need to be combined to promote university students' start-ups. The university factors that promote the start-up of university students were found to be scholarships, start-up grants, startup lectures, and startup clubs. Third, the openness and regional characteristics of the univeristy can promote the establishment of university students. Fourth, the establishment of a research environment and support for start-ups for full-time faculty members can enhance their start-up performance. The university factors that promote the start-up of full-time faculty were research funds and staffes who support start-up. The conclusions drawn from these findings are as follows. First, overall efforts are needed to develop into an entrepreneurial university. Second, in order to change into an entrepreneurial university, direct support for entrepreneurship is needed. Third, as an entrepreneurial university, it is necessary to find a way to bridge the gap by university according to region and size. Fourth, it is necessary to reinforce the support for linking the research results of universities to start-ups. Fifth, it is necessary to improve the atmosphere for full-time faculty members to be entrepreneur.

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

  • Yoo, Eun-Kyung;Suh, Moon-Ja
    • The Journal of Korean Academic Society of Nursing Education
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    • v.6 no.2
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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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Development of Jeju Local Food Tour Package and Economic Value Estimation based on Contingent Valuation Method (제주 향토음식을 활용한 음식관광상품 개발 및 CVM을 적용한 경제적 가치 평가)

  • Ahn, So-jung;Yoon, Ji-young
    • Journal of the East Asian Society of Dietary Life
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    • v.26 no.4
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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.