• Proceedings of the Korean Vacuum Society Conference
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• 2012.08a
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• pp.439-439
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• 2012

태양광 발전은 발전 셀의 특성상 태양광의 일사량, 태양과 셀 단면이 이루는 각도에 따라서 발전량의 차이를 가져온다. 실리콘 태양전지의 전면 texturing은 입사광의 반사율을 크게 감소시키고, 태양전지 내에서 빛의 통과길이를 증가시켜 태양전지 내의 흡수하는 빛의 양을 증가 시키는 역할을 한다. 따라서 전면 texturing은 단락전류를 증대시키는 효과를 가지고 온다. 일반적으로 texturing은 alkaline etching (WET) 공정과 reactive ion etching (RIE) 공정이 사용된다. 그리고 다결정 실리콘 태양전지의 경우에는 재료의 결정방향에 따라 식각이 되어지는 WET 공정의 경우 texturing 모양을 제어할 수 없어 효과적이지 못하는 결과를 가지고 온다. 본 연구에서는 Electroluminescence을 측정하여 RIE, WET 공정을 사용하여 만든 texturing 구조의 다결정 태양전지의 Microcrack 및 Defect, Electrode Failure, Hot spot등을 검출하였으며, ${\mu}$-PCD 측정 결과와 비교 분석하여 Micro carrier life time을 유추하여 계산하였다. 또한 반사율을 측정해본 결과 WET 공정 대비 RIE의 경우 단파장영역에서 반사율이 크게 감소하여, 상대적으로 높은 External quantum efficiency (EQE)가 측정되었다. 이는 Jsc를 증가시켜, 태양전지의 효율이 증가되는 결과를 얻을 수 있었다.

• Journal of the Korean GEO-environmental Society
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• v.15 no.12
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• pp.53-59
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• 2014

In order to obtain basic data for reasonable design of rockfall prevention net unreasonably being designed according to experiences, this paper determined a standard cross section and analyzed the effects of parameters such as inclination and height of slope faces, rockfall weight, separation distance on rockfall behaviors such as bounce height, kinetic energy and passage rate. The weight of rockfall changed from 400 kg to 700 kg and then to 1,000 kg. With the height of 20 m as the standard, the test was conducted with the inclination at $63^{\circ}$ and $55^{\circ}$ which may affect rockfall behaviors. Analysis was made while changing the fall height of rockfall from 3 m to 15 m and then to 20 m, thereby analyzing and evaluating changes in maximal kinetic energy occurring in the base of slope. According to the analysis result, in designing a rockfall prevention wire net, a design considering various conditions including inclination of the slope, expected size or weight of rockfall, situation of the slope and the shape of rockfall, and rockfall trace is judged necessary beyond the current uniform application.

• Parasites, Hosts and Diseases
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• v.31 no.3
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• pp.183-192
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• 1993

A transmission electron microscopic study was performed to observe the ultrastructures of the male germinal cells and spermatozoa of Fibricola seoulensis. Spermatogonia were found in the periphery of the testis and characterized by large nuclei and comparatively little cytoplasms. Spermatocytes contained an oval to spherical nucleus. Their nuclear volume was little larger in comparative to that of cytoplasm, and the chromatin was comparatively little. The early spermatids were characterized by a great amount of cytoplasm, and numerous mitochondria encircled the nucleus. In a more advanced spermatids the electron-dense strands of chromatin appeared in the nucleus, and a pair of rootlet of the axoneme and a microtubule-organizing center (MTOC) were observed near the nucleus. The sectioned spermatozoa were found in the testis and the seminal vesicle. Their cross sectional views were divided into 6 types when they were distinguished on the basis of the morphology and components. The spermatozoa of F. seoulensis showed two flagella of 9+1 type axoneme.

• Journal of the Korean Society of Hazard Mitigation
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• v.2 no.2 s.5
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• pp.95-104
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• 2002

This paper presents the pull-out failure mode on Headed Bars and prediction of tensile capacity, as governed by concrete cone failure. 17 different plate types, three different concrete strengths and three different welding types of specimens were simulated. Test variables are the reinforcing bar diameters connected to headed plate (e.g., 16mm, 19mm and 22mm), the head plate shapes (e.g., circular, square, rectangular), the dimensions of head plates (e.g., area and thickness), the types of welding scheme for connection of reinforcing bars and head plates (e.g., general welding and friction welding). Headed Bars were manufactured in different areas, which shape and thickness are based on ASTM 970-98. Calculation of Embedment length in concrete is based on CSA 23.3-94, and static tensile load was applied. Pullout capacities tested were compared to the values determined using current design methods such as ACI-349 and CCD method. If compare experiment results and existings, Headed bar expressed high strength and bigger breakdown radious than standard by wide plate area and anomaly reinforcing rod unlike anchor.

• The Journal of Korean Orthopaedic Ultrasound Society
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• v.1 no.1
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• pp.64-72
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• 2008

Compression neuropathy around elbow and wrist are one of the common disturbing problems in the upper extremity. The understanding of normal nerve architectures and pathophysiologic changes in compression neuropathy is important to interpret the ultrasonographic images correctly. Compression neuropathies have characteristic ultrasonographic imaging features of flattened nerve at compression and hypoechoic swollen nerve with loss of fascicular patterns at proximal segments. Dynamic ultrasonographic imagings on motion can show dymanic subluxation of ulnar nerve and medial head of triceps muscle over the medial epicondyle in snapping triceps syndrome. Dynamic compression of median nerve also can be visualized in pronator teres syndrome by dynamic imaging studies. A quantitative measures of cross sectional area or compression ratio can be helpful to diagnose compression neuropathies, such as carpal tunnel syndrome or cubital tunnel syndrome. With the clinical features and electeophysiologic studies, the untrasonographic imagings are useful tool for evaluation of the compression neuropathies in the upper extremities.

• Journal of Korea Game Society
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• v.9 no.5
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• pp.137-144
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• 2009

This paper predicts 6 facial regions that may have sharply different scattering properties, rendering the face more realistically based on their diffusion profiles. The scattering properties are acquired in the form of high dynamic range by photographing the pattern formed around an unit ray incident on facial skin. The acquired data are fitted to a 'linear combination of Gaussian functions', which well approximates the original diffusion profile of skin and has good characteristics as the filter. During the process, to prevent its solutions from converging into local minima, we take advantage of the genetic algorithm to set up the initial value. Each Gaussian term is applied to the irradiance map as a filter, expressing subsurface scattering effect. In this paper, to efficiently handle the maximum 12 Gaussian filterings, we make use of the parallel capacity of CUDA.

• The Journal of the Petrological Society of Korea
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• v.19 no.4
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• pp.293-301
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• 2010

The Ipbong Andesite is a stratigraphic unit which is lain in the lowermost part of the Yucheon Group in the southeastern Yeongyang sbbasin. The Ipbong Andesite is lain on the Sinyangdong Formation and under the dacitic tuff, and consists in its lower andesitic tuffs and upper lavas. The andesitic lavas show some alignments of elongate vesicles filling with calcite amygdules and plagioclase microphenocrysts, and show rare imbrication of the microphenocrysts in vertical sections parallel to them. The flow directions which is measured from the flow indicators are laid along NNW-SSE trend in the eastern part and NNESSW in the southwestern part of the study area. Movement pattern from the flow lineations suggests that the Ipbong Andesite had a fanlike pattern by flowing southwards from the mid-northern part. Accordingly a small diorite stock in the mid-northern part area may probably be a source area of the Ipbong Andesite.

• Journal of Veterinary Clinics
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• v.30 no.5
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• pp.399-402
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• 2013

An 8-year-old, female, mixed Thoroughbred horse was presented for the evaluation of the left upper eyelid mass with ocular discharge during 4 months. After unilateral surgery, excised eyelid mass and left eye were submitted for diagnosis. Grossly, the removed mass was $6{\times}7{\times}2$ cm in size and dome shape with rough irregular surface. On the cut surface, mass was firm and yellowish white in color. Histopathologically, severely proliferated stratified squamous epithelia were heavily invaginated into dermis, and then formed rete ridge or numerous squamous islands. These neoplastic islands were composed of multiple layers of prickle cells with intercellular bridge and central laminated keratin pearls or necrotic cellular debris. Based on the above results, this case was diagnosed as squamous cell carcinoma in upper eyelid of horse.

• Journal of the Korean Geotechnical Society
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• v.20 no.4
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• pp.65-74
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• 2004

Based on the field measuring data obtained from seven excavation sections in Inchon International Airport Project, the horizontal displacement of sheet piling walls supported by anchors and the lateral earth pressure acting on sheet piling walls was investigated in soft ground. The proposed diagram of lateral earth pressure is a rectangular form, and the maximum earth pressure corresponds to $0.6\gamma H$. The maximum earth pressure is similar to the empirical earth pressure proposed by NAVFAC(1982). The quantitative safe criterion of sheet piling walls with struts is established from the relationships between increasing velocity of maximum horizontal displacement and stability number in excavated ground. If the velocity of maximum horizontal displacement shows lower than 1mm per day, the sheet piling walls exist under stable state. When the velocity of maximum horizontal displacement becomes more than 1mm and less than 2mm per day, excavation works should be observed with caution. Also, when the velocity of maximum horizontal displacement becomes more than 2mm per day, appropriate remediations and reinforcements are applied to sheet piling walls.

• Journal of radiological science and technology
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• v.39 no.3
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• pp.337-344
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• 2016

The purpose of this study was to evaluate the radiolucency for the phantom output to the 3D printing technology. The 3D printing technology was applied for FDM (fused deposition modeling) method and was used the material of ABS (acrylonitrile butadiene styrene) resin. The phantom was designed in cylindrical uniformity. An image uniformity was measured by a cross-sectional images of the 3D printed phantom obtained from the CT equipment. The evaluation of radiolucency was measured exposure dose by the inserted ion-chamber from the 3D printed phantom. As a results, the average of uniformity in the cross-sectional CT image was 2.70 HU and the correlation of radiolucency between PMMA CT phantom and 3D printed ABS phantom is found to have a high correlation to 0.976. In the future, this results will be expected to be used as the basis for the phantom production of the radiation quality control by used 3D printing technology.