• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.26 no.3
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• pp.246-251
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• 2013

Screen printing is commonly used to form the front/back electrodes in silicon solar cell. But it has caused high resistance and low aspect ratio, resulting in decreased conversion efficiency in solar cell. Recently the plating method has been combined with screen-printed c-Si solar cell to reduce the resistance and improve the aspect ratio. In this paper, we investigated the effect of light induced silver plating with screen-printed c-Si solar cells and compared their electrical properties. All wafers were textured, doped, and coated with anti-reflection layer. The metallization process was carried out with screen-printing, followed by co-fired. Then we performed light induced Ag plating by changing the plating time in the range of 20 sec~5min with/without external light. For comparison, we measured the light I-V characteristics and electrode width by optical microscope. During plating, silver ions fill the porous structure established in rapid silver particle sintering during co-firing step, which results in resistance decrease and efficiency improvement. The plating rate was increased in presence of light lamp, resulting in widening the electrode with and reducing the short-circuit current by shadowing loss. With the optimized plating condition, the conversion efficiency of solar cells was increased by 0.4% due to decreased series resistance. Finally we obtained the short-circuit current of 8.66 A, open-circuit voltage of 0.632 V, fill factor of 78.2%, and efficiency of 17.8% on a silicon solar cell.

• Journal of Korean society of Dental Hygiene
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• v.20 no.6
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• pp.937-947
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• 2020

Objectives: This study was conducted to investigate the factors that prevent dental patients from visiting the dental clinic. Methods: From June 22, 2020 to July 17, 2020, among patients 10 years or older who had visited the dental clinic, 314 individuals who agreed to the study were asked to fill out a self-administered questionnaire. The data were analyzed using the SPSS Statistics 22.0 program, and the significance level was set at 0.05. Results: The dental avoidance factors according to the general characteristics were high in women and housewives, and among the dental-related characteristics, the most common reason for visiting the dental clinic was experiencing pain. The factors influencing anxiety were fear, environment, stimulus, age, and exercise, and the factors influencing the fear were anxiety, stimulus, subjective oral health status, education, and exercise. The factors influencing the stimulus were environmental factors, fear, anxiety, and age, and the factors that influenced environmental factors were stimulus and anxiety. Conclusions: There is a need to develop measures and policies to overcome fear of dental procedures, such as developing a dental experience program and allowing patients to experience dental fear and anxiety in advance.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.08a
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• pp.432-433
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• 2012

Polymer solar cells are fabricated using electrospray (e-spray) deposition process. It shows comparable performance with reference devices, and has different characteristics according to the thickness of the active layer: In the case of the devices with higher fill factor, it shows relatively lower current density, and vice versa. These films are characterized by atomic force microscopy measurement. The results indicate that the comparable power conversion efficiency made by e-spray results from the 'solvent annealing effect' by process conditions and the different thin film property is caused by the degree of self-organization of the polymer.

• 한국신재생에너지학회:학술대회논문집
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• 2010.11a
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• pp.39.1-39.1
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• 2010

이종접합태양전지는 단결정 실리콘 기판 표면에 고품질 비정질 실리콘층을 적층함으로써 전기의 근원인 전하의 재결합 손실을 줄여 높은 개방전압을 얻을 수 있다는 특징이 있다. 초박형 태양전지는 기존 태양전지보다 뛰어난 광전변환 특성(Photovoltaic characteristic)을 가지고 두께가 얇아 제품 형상 시 자유도가 높아진다. 본 논문에서는 n-type Bare wafer($160{\sim}180{\mu}m$)를 이용하여 $50{\mu}m$의 웨이퍼를 제작하였다. a-Si:H(p)_a-Si:H(i)_c-Si(n)의 광흡수층 구조를 성막하여 cell을 제작하였다. 그 결과 Voc(Open Circuit Voltage)가 0.666, Jsc(Short-Circuit Current)가 34.77, FF(Fill Factor) 69.413, Efficency 16.07%를 달성했다.

• Proceedings of the Korean Vacuum Society Conference
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• 2015.08a
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• pp.257.2-257.2
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• 2015

In this paper, we report on the 10.33% efficient thin film/bulk tandem solar cells with the top cell made of amorphous silicon thin film and p-type bulk crystalline silicon bottom cell. The tunneling junction layers were used the doped nanocrystalline Si layers. It has to allow an ohmic and low resistive connection. For player and n-layer, crystalline volume fraction is ~86%, ~88% and dark conductivity is $3.28{\times}10-2S/cm$, $3.03{\times}10-1S/cm$, respectively. Optimization of the tunneling junction results in fill factor of 66.16 % and open circuit voltage of 1.39 V. The open circuit voltage was closed to the sum of those of the sub-cells. This tandem structure could enable the effective development of a new concept of high-efficiency and low cost cells.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1995.05a
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• pp.145-149
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• 1995

The metallization is the key to determining cell costs, call performance, and cell and system reliabiltiy. The Burled Contact Solar Cell (BCSC) was specifical1y desinged to be compatible tilth low cost, mass production techniques and avoid the conventional metallization problem. By using electroless plating trchniqeu, we performed this metallization inexpensively and reliabley, This paper presents the details of the optimization procedure of metallization schemes on laser grooved cell surface Commercially available Ni ,Cu, and Ag plating solutions were applied for the cell metallization. The application of those solutions on the buried contact front metalization has resulted in an cell efficiency of 18.5% The cell parameters are an open circuit voltage of 651 mV, short circuit current density of 38.6 mA/$\textrm{cm}^2$, and fill factor of 73.5%.

• Proceedings of the KIEE Conference
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• 2006.04b
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• pp.203-205
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• 2006

This paper presents a study on the winding method and structure of core of single phase induction motor in order to design the high efficiency motor. In case of single phase induction motor, winding fill factor and the number of turns in each slot are not uniform in general. Moreover, these can be the critical parameters for high efficiency design in case the size of motor should be restricted within certain volume. Therefore, we should analyze the effects of these parameters related to efficiency parameter. The characteristic analysis was performed by using FEM.

• International Journal of Costume and Fashion
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• v.16 no.1
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• pp.55-70
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• 2016

The existing research on sustainability in the apparel industry provides no clear consensus on the definition of sustainability for the apparel brands and how sustainability of apparel brands as it is perceived by consumers can be measured. To fill this gap in research, the present study proposes and tests a confirmatory model of sustainability for apparel brands based on the three pillars of sustainability (i.e., economic, environmental, social sustainability) theorized in the Triple Bottom Line model. A survey of 754 U.S. consumers provided data for empirical testing. The results support the three-dimensional factor structure of sustainability for apparel brands and reveal that a second-order sustainability exerts a significant impact on both brand image and brand trust. The findings provide theoretical implications for researchers and practical managerial suggestions for marketers.

• 한국신재생에너지학회:학술대회논문집
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• 2008.05a
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• pp.425-427
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• 2008

Active area of dye-sensitized solar cell (DSSC) has an effect on the efficiency of DSSC. As the active area increases, the efficiency goes down in a general way. This is caused by the increase of internal resistance in DSSC. The internal resistances are related to various resistant elements. The charge transfer processes at Pt counter electrode and the sheet resistance of TCO are two of these resistant elements. In this study, we try to divide the active area into several small sections in a large sized cell to reduce these two internal resistant elements. As a result, we find out that the fill factor is increased and then the conversion efficiency is improved as the number of dividing active area into several small sections is increased.

• 한국신재생에너지학회:학술대회논문집
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• 2008.05a
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• pp.438-440
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• 2008

Effects of Ga contents of CIGS absorber layer on the performance of thin films solar cells were investigated. As Ga content increased, the grain size of CIGS films decreased presumably because Ga diffusion during 2nd stage of co-evaporation process is more difficult than In diffusion. Performances of corresponding solar cell show systematic dependence on Ga content in which open circuit voltage increases and short circuit current and fill factor decrease as Ga contents increases. At a optimal condition of Ga/(In+Ga)=0.27, the solar cell shows a conversion efficiency of 15.6% with $V_{OC}$ of 0.625 V, $J_{SC}$ of 35.03 mA/$cm^2$ and FF of 71.3%.