• 한국태양에너지학회:학술대회논문집
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• 2011.04a
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• pp.116-120
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• 2011

In this paper, we studied the optimization of the screen pringting method for crystalline silicon solar cell fabrication. The 156 * 156 mm2 p-type silicon wafers with $200{\mu}m$ thickness and $0.5-3{\Omega}cm$ resistivity were used after texturing, doping, and passivation. Screen printing method is a common way to make the c-Si solar cell with low-cost and high-efficiency. We studied the optimized condition for screen printing with crystalline silicon solar cell as changing the printing direction (finger line or bus bar), finger width, and mesh angle. As a result, the screen printing with finger line direction showed higher finger height and better conversion efficiency, compared with one with bus bar direction. The experiments with various finger widths and mesh angles were also carried out. The characteristics of solar cells was obtained by measuring light current-voltage, optical microscope and electroluminescence.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.25 no.12
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• pp.1015-1020
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• 2012

Resistance of the front electrode is the highest proportion of the ingredients of the series resistance in crystalline silicon solar cell. While resistance of the front electrode is decreased with larger area, it induces the optical loss, causing the conversion efficiency drop. Therefore the front electrode with high aspect ratio increasing its height and decreasing is necessary for high-efficiency solar cell in considering shadowing loss and resistance of front electrode. In this paper, we used the screen printing method to form high aspect ratio electrode by multiple printing. Screen printing is the straightforward technology to establish the electrodes in silicon solar cell fabrication. The several printed front electrodes with Ag paste on silicon wafer showed the significantly increased height and slightly widen finger. As a result, the resistance of the front electrode was decreased with multiple printing even if it slightly increased the shadowing loss. We showed the improved electrical characteristics for c-Si solar cell with repeatedly printed front electrode by 0.5%. It lays a foundation for high efficiency solar cell with high aspect ratio electrode using screen printing.

• Journal of Environmental Science International
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• v.7 no.6
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• pp.783-791
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• 1998

The objectives of this study were to investigate the characteristics of desulfurization under different experimental conditions and the effects of desulfurization bed fluidized bed combuster installed with the screen. The experimental results were as follows ; First, as the height of fluidized bed combustor becomes higher, the concentrations of $SO_2$ mainly increased and sulfur retion of paper sludge was higher than that of natural limestone. Second, the desulfurzation by natural limestone occurred at in-bed and the desulfurization by paper sludge occurred in the whole of fluidized bed combuster. In addition, we identified calcium sulfate by the analysis of SEM and XRD. Third, screen at splash region increased sulfur retention 2~5%, air velocity and anthracite fraction had a little effect on the sulfur retention.

• Journal of Korean Society for Atmospheric Environment
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• v.9 no.2
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• pp.168-173
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• 1993

Air quality impacts of point and area sources were analyzed by using ISCST2 with wind speed and stability class combinations of SCREEN. Stack height was important in determining the impact of point sources. With the stack height reduced to 21m from 75m, the concentration in the vicinity increased several times in spite of decreasing the emission rate by half. When the emission rates were same, concentrations from an area source of 10m release height were slightly lower than those from a point source of 21m stack height at the plume centerline. Bur the area source resulted in larger area of high concentration. Concentration from the point source was high in neutral to slightly unstable conditions with strong winds in a short distance, and in stable conditions with weak winds in a long distance. Concentration from the area source decreased with distance from the source, and was high in stable conditions with weak winds.

• Journal of the Ergonomics Society of Korea
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• v.10 no.2
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• pp.3-13
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• 1991

As the VDT work constrains work postures because of its work characteristics. VDT worksta- tions should be properly designed so as to be fitted to various types of physical conditions of op- erators. Therefore, in this study, the preferred settings of VDT wrokstation dimensions of operators. Therefore, in this study, the preferred settings of VDT workstation dimensions and work postures were studied in order to determine the appropriate dimensions and the work postures for VDT operators which will alleviate the musculoskeletal troubles or visual fatigue. The scpoe of the study is as follows. 1. Measurement and analysis of the preferred settings of the height of workstation, keyboard, seat, and screen among the experienced VDT operators. 2. Anaysis of the relationship between the preferred settings of workstation height and the seat height control among the experienced VDT operators. 3. Analysis of the work postures of the experienced VDT operators.

• Industrial Engineering and Management Systems
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• v.6 no.2
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• pp.146-157
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• 2007

This paper discusses two algorithms for recommending notebook computer (NBC) and workstation adjustments so that the user can assume an ergonomic seated posture during NBC operation. Required input data are the user's anthropometric data and physical dimensions of the NBC and the workstation. The first algorithm is based on an assumption that there are no workstation constraints while the second algorithm considers the actual seat height and work surface height. The results from the algorithms include recommendations for adjusting the NBC (tilt angle of the NBC base unit, angle between the base and screen units, and base support height) and the workstation (heights of seat support and footrest, and distance between the body and the NBC).

• The Journal of the Korea institute of electronic communication sciences
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• v.16 no.1
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• pp.117-124
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• 2021

Among growth disorders, 'Short Stature' can be improved through rapid diagnosis and treatment, and for that, it is important to detect early'Short Stature'. It is recommended to measure the height steadily for early detection of 'Short Stature' and checking the kid's growth process, but existing height measurement methods have problems such as time and space limitations, cost occurrence, and difficulty in keeping records. So in this paper, we proposed an 'Development of Kid Height Measurement Application based on Image using computer vision' method using smart phones, a medium that is highly accessible to people. In images taken through a smartphone camera, the kid's height is measured using algorithms from OpenCV, a computer vision library, and the measured heights were printed on the screen through 'a comparison graph with the standard height by gender and age' and 'list by date', made possible to check the kid's growth process. It is expected to measure height anytime, anywhere without time and space limitations and costs through this proposed method, and it is expected to help early detection of 'Short Stature' and other disorder through steady height measurement and confirmation of growth process.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.687-687
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• 2013

In rearpoint contact solar cell and the PERC (passivated emitter rear contact) type cell, surfaces were passivated by SiO2 or Al2O3 to increase solar cell efficiency. Therefore, we have investigated the effect of surface passivation for crystalline silicon solarcell using mass-production atomic layer deposited (ALD) Al2O3. The patttern which consists of cylinders with 100um diameter and 5um height was formed by PR patterning on Si (100) substrate and then Al2O3 of about 10nm and 20nm thickness was deposited by ALD. The pattern in 10 nm Al2O3 film was removed by dipping in aceton solution for about 10 min but the pattern in 20 nm Al2O3 film was not. The influences of process temperature and heat treatment were investigated using microwave photoconductance decay (PCD) and Quasi-Steady-State photoconductance (QSSPC). The solar cell process used in this work combines the advantage of using the applicability of a selective deposition associated with a ALD passivation and the use of low-cost screen print for the contacts formation.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.25 no.7
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• pp.767-773
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• 2014

This paper presents the reduction characteristics of electromagnetic penetration through a slit in conducting screen by loaded plate. The FDTD method is used in theoretical analysis. And the characteristics of penetrated electric fields are calculated in terms of length, width, shape, position, and height of the loaded plate to find out how the geometry of plate influences the reduction characteristics of the electromagnetic penetration and shielding effectiveness. The results show that the characteristics of penetrated electric field and shielding effectiveness depend on the geometry of loaded plate. In particular, the optimal geometry of loaded plate which minimize penetrated electric field are verified.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.23 no.9
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• pp.1094-1099
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• 2012

This paper presents the reduction characteristics of electromagnetic penetration through a slot in conducting screen by loaded plate. The FDTD method is used in theoretical analysis. And the characteristics of penetrated electric fields are calculated in terms of length, width, position, and height of the loaded plate to find out how the geometry of plate influences the reduction characteristics of the electromagnetic penetration. The results show that the characteristics of penetrated electric field depend on the geometry of loaded plate. In particular, the optimal geometry of loaded plate which minimize penetrated electric field are verified.