• KIEAE Journal
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• v.17 no.3
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• pp.69-74
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• 2017

Purpose: The apartment complex constructed recently is composed of very various types of building, plan, and orientation etc. However, it is difficult to remark conclusively that these various types of buildings are designed energy-effectively, since it is difficult for architects to find useful energy design guideline for decision making. By the preceding study, the present condition and problem about this subject was grasped, apartment building types were examined and representative types were extracted. Method: Large apartment building complex having 1940 households, located in haengbok-dosi, sejong city, Korea is used as an example to conduct this study. Representative building types are extracted first. Then, heating and cooling load of households is analyzed. Lastly, effect of outdoor air cooling is investigated by computer simulation. Result: Results of this research are summarized as follows: 1. Besides solar gain, household layout of building, orientation, and plan have compositive effects on heating and cooling load. 2. The effect of outdoor air cooling in apartment can be improved by arranging windows of households.

• Environmental Analysis Health and Toxicology
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• v.23 no.2
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• pp.87-91
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• 2008

In this study, three different sizes of cerium oxide ($CeO_2$) nanoparticles were synthesized and exposed to Caenorhabditis elegans to investigate the potential harmful effect of $CeO_2$ nanoparticles on the environment. The effects of the $CeO_2$ nanoparticles on C. elegans were assessed at multiple levels, such as with respect to stress response gene expression, growth, reproduction and mortality. Moreover, to test the ecotoxicological relevance of $CeO_2$-induced gene expression. The overall results suggest that $CeO_2$ nanoparticles may provoke ecotoxicity in C. elegans especially with respect to gene expression, reproduction and survival, which can comprise an important contribution to knowledge on the ecotoxicity of $CeO_2$ nanoparticles, about which little data are available. This is particularly valuable in the biomarker research on ecotoxicology, as ecological relevance is a crucial criterion for the applicability of the biomarker in field biomonitoring and ecological risk assessment.

• The Journal of Internal Korean Medicine
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• v.39 no.5
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• pp.879-885
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• 2018

Background: A herniated intervertebral disc (HIVD) triggers low back pain (LBP). Korean conservative treatment can decrease the herniated disc size without traditional surgery, but detailed prognosis is unclear. Case summary: One patient presented with LBP and bilateral sciatica. She was diagnosed with lumbar HIVD by magnetic resonance imaging (MRI) and treated by Korean medicine (acupuncture, decoction, and physical therapy). For 6 months, MRI follow-up exams showed the aggravation and migration of L5-S1 followed by distinct improvement of the same lumbar vertebra. Conclusion: The disc size in a patient with lumbar HIVD was reduced by Korean conservative treatment, and periodic radiologic examination showed the previously unrecognized process of absorbing the disc.

• Toxicological Research
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• v.22 no.4
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• pp.397-402
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• 2006

Lipid mediator such as lysophosphatidic acid (LPA) plays an important role in inflammation and wound heating, has been recently reported to induce influx of extracellular calcium into erythrocytes. This elevation in intracellular calcium level may cause destruction of membrane asymmetry and procoagulant microvesicle formation. Thus, we investigated if the lipid mediator could induce microvesicle formation as a result of extracellular calcium influx in human erythrocytes. Treatment with lipid mediator to erythrocytes resulted in microvesicle generation In a concentration-, time-dependent manner. Microvesicles formed expressed procoagulant phosphatidylserine (PS) on their surface membrane significantly as well. LPA did not affect the band 3 phosphorylation which is involved in morphological change in erythrocytes. Pretreatment with suramin did not inhibit LPA-induced microvesicle generation, suggesting microvesicle generation was not receptor-dependent pathway. Depletion of intracellular ATP levels in erythrocytes was suggested to be one of the mechanism for these events.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2006.05a
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• pp.487-488
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• 2006

Picosecond (ps) laser micro-machining has emerged as an attractive method of fabricating high-precision microstructures, especially in metals. In this paper, a metallic mold for diffraction gratings is fabricated with a mode-locked 12 Ps $Nd:YVO_4$ laser. Laser pulses with a wavelength of 355nm are irradiated on the surface of NOK 80, a mold material, to generate line patterns. In order to minimize the line width, laser power is set just above the ablation threshold of NOK 80. Results show that the spectrum from the fabricated mold is good enough for some industrial application.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.25 no.5
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• pp.362-367
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• 2016

Recently, wireless charging systems have expanded their applications from household electrical appliances to outdoor activity devices. In wireless charging systems, solar cells have versatile advantages, such as abundant raw materials within the earth, reasonable prices of products, and highest power conversion efficiency. In this study, the photovoltaic effect between a silicon solar cell and a photon of infrared wavelength was simulated using a Shockley diode equation. A solar cell power charging system was then set up to: 1) clarify mechanisms of the charging interaction based on the photovoltaic effect with a laser source, and 2) verify interdependency of the parameters: laser settings and geometrical position between a solar cell and the laser. As was observed, the solar cell generates more power when the photon was irradiated uniformly, intensively, and vertically on the surface of the solar cell.

• Laser Solutions
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• v.9 no.3
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• pp.1-5
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• 2006

Diffraction grating is the optical device which has periodic pattern. Decorative logotypes is the one of application of diffraction grating. In this paper diffraction grating for decorative logotype is fabricated by dot pattern in stead of line pattern. A metallic mold for diffraction gratings is fabricated with a mode-locked 12 ps Nd:YVO4 laser. Laser pulses with a wavelength of 355nm are irradiated on the surface of NOK 80, a mold material, to generate dot patterns. In order to minimize the dot diameter, laser power is set just above the ablation threshold of NOK 80. Results show that the spectrum from the fabricated mold is good enough for some industrial application

• Journal of the Korean Society for Library and Information Science
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• v.36 no.3
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• pp.133-153
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• 2002

This study intends to make a comprehensive investigation on the present stage of library catalogs in Korea. To the end, this study analyzed the utility of the library catalog from both librarians' and end-user's viewpoint. Emphasis was on analyzing the different viewpoints between these two groups and on verifying the problems of library catalogs in such a rapidly changing information environments. The result of this study is expected to be useful in preparing both strategies and methods to enhance the utility of library catalogs.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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• pp.291-291
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• 2011

플라즈마에 노출된 재료 표면의 온도 증가는 다음과 같은 요인에 의해서 결정된다. 이온의 충돌에 의한 역학적 에너지, 이온의 중성화, 라디칼의 안정화에 의한 에너지 방출(잠열, latent heat), 플라즈마에서 방출된 빛의 흡수. 이중 식각을 위한 기판 바이어스에 의해서 주로 결정되는 이온 충돌 에너지와 잠열의 방출이 300 mm wafer용 유도 결합 플라즈마 식각 장치에서 소스 전력과 바이어스 전력에 따라서 어떻게 변화하는지 전산 유체 역학 모사 프로그램인 CFD-ACE를 이용하여 상용 식각 장비인 AMAT사의 DPS II를 대상으로 온도 분포의 변화를 계산하였다. 실험 결과와 비교를 위하여 다섯 곳에(상, 하, 좌, 우, 중심) 열전대를 부착한 온도 측정 웨이퍼를 기판의 위치에 설치하고 여러 가지 실험 조건에 대해서 온도의 변화를 측정하였다. Ar 10 mTorr에서 2열 병렬 안테나의 전력을 300 W에서 시간에 따른 온도의 변화를 측정하였다. 이때 wafer의 평균 온도는 $28.9^{\circ}C$에서 $150^{\circ}C$까지 12분 내에 상승하였으며 최고 온도에 도달한 다음에는 거의 일정하게 유지 되었다. Si의 식각에서 온도의 영향을 가장 크게 받는 반응은 F 라디칼에 의한 Si의 직접 식각이며 Arrhenius 식의 형태로 표현하면 0.116*exp (-1250/T)의 형태로 된다. 문헌에 보고된 계수를 이용해서 $29^{\circ}C$의 식각 속도와 플라즈마에 의한 가열 최고 온도인 $150^{\circ}C$ 때의 값을 비교해보면 3.3배의 차이가 난다. 따라서 4%내의 식각 균일도를 목표로 하는 폴리 실리콘 게이트 식각 장비의 설계에서는 플라즈마에 의한 가열 불균일을 상쇄 할 수 있는 히터와 냉각 구조의 최적 설계가 필요하다.

• Laser Solutions
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• v.15 no.4
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• pp.12-15
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• 2012

On behalf of the existing semiconductor process, the electronic devices to low-cost mass production to mass print the way, the research for development of roll-to-roll printing process is actively underway. This study was performed in about the research on the manufacturing technology of the printing roll used in the printing process of electronic devices. The indirect laser imprinting technology was used to create printable roll, and after coating copper on the surface of steel and thereon after coating polymer, after removing the polymer on the surface of roll, the printable roll was made. The laser system and roll feeder system were constructed and control program was developed. We has found the optimal conditions to perform laser patterning experiments using a system developed and We can make the minimum line width of 18 ${\mu}m$.