• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.1442-1443
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• 2008

본 논문에서는 인쇄회로기판과 도전체 샤시(Chassis)가 연결되었을 때의 복사성 방사(Radiated Emission)의 감소에 대해서 연구하였다. Current Driven 메커니즘 등가회로를 사용하여 전자파 방사의 주요한 원인중 하나인 Common-mode Current를 인쇄회로기판과 Chassis가 연결된 구조에 적용하였다. Chassis의 유무에 따라 복사성 방사의 감소를 확인하고자 2-layer 인쇄회로기판과 SECC(Steel Electro galvanized Cold-rolled Coil) 재질의 Chassis를 나사(Screw)를 통하여 전기적으로 연결하였을 때를 시뮬레이션 하였고, 제작된 구조물을 3m 무반향실에서 복사성 방사를 측정한 후 시뮬레이션과 결과를 비교하였다. 결과로 30MHz$\sim$45MHz에서 최대 10dB 감소의 효과가 있음을 확인하였다.

• Journal of Technologic Dentistry
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• v.41 no.4
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• pp.287-293
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• 2019

Purpose: To evaluate the accuracy of the 3D printed die models and to investigate its clinical applicability. Methods: Stone die models were fabricated from conventional impressions(stone die model; SDM, n=7). 3D virtual models obtained from the digital impressions were manufactured as a 3D printed die models using a 3D printer(3D printed die models;3DM, n=7). Reference model, stone die models and 3D printed die models were scanned with a reference scanner. All dies model dataset were superimposed with the reference model file by the "Best fit alignment" method using 3D analysis software. Statistical analysis was performed using the independent t-test and 2-way ANOVA (α=.05). Results: The RMS value of the 3D printed die model was significantly larger than the RMS value of the stone die model (P<.001). As a result of 2-way ANOVA, significant differences were found between the model group (P<.001) and the part (P<.001), and their interaction effects (P<.001). Conclusion: The 3D printed die model showed lower accuracy than the stone die model. Therefore, it is necessary to further improve the performance of 3D printer in order to apply the 3D printed model in prosthodontics.

• Journal of the Korean Society for Precision Engineering
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• v.20 no.10
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• pp.12-21
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• 2003

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2015.10a
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• pp.988-991
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• 2015

3D printing technology is instrument that can create real objects in three-dimensional space, as printed on paper, if the three-dimensional designs are made. 3D printing technology has been recently used in various field of medicine, and also biomedical application of three dimensional printing technology remains one of the most important research topics until now. 3D printing technology is causing a revolutionary change in the overall automotive manufacturing, aerospace, marine, medical and so on. The medical industry applications of current 3D printer are a virtual simulation, custom medical implants manufactured, practice of medical personnel. In this study, we analyzed 3D printing technology and application cases for medical services.

• Journal of the Korea Furniture Society
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• v.10 no.2
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• pp.79-86
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• 1999

본 연구는 국내가구 디자인 산업의 경쟁력 강화를 위한 사례의 하나로 디자인 작품을 시도하게 되었다. 지존의 디자인 모델링은 소프트 모델 또는 목업(mock up)개념에서 시행되어 디자이너가 직접 제작하기 전에는 3차원의 형상을 구현하기가 어려웠으며, 더욱이 문야의 적용은 실크스크린 또는 인쇄와 같은 처리기법으로 사용되었다. 이 방법은 시간, 경비, 공간, 자료의 보관 및 축적, 기타의 많은 문제점과 생산성 향상에 애로사항이 되어왔다. 요지와 같이 많은 문제점과 렌더링의 데이터베이스 뱅크는 활용 가능한 분야와 직종에 따라서 응용 가능하기 때문에 많은 실험적 시도가 요구된다. 디자인의 발상은 우리나라 전통문화의 가구디자인을 접목시킨 사례로서 시도하였으며, 형태와 문양을 현대적 개념에서 재해석하여 대입시켰다. 적용디자인 사례는 2개의 모델에 10가지의 패턴을 복합적으로 활용한 디자인 작품의 결과물이다. 이러한 결과는 다양한 디자인 연출과 시안을 추출할 수 있으며, 디자인 활동과 설계에 능률을 배가시키는 효과를 검증할 수 있겠다.

• Journal of the Korean Graphic Arts Communication Society
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• v.29 no.1
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• pp.75-83
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• 2011

As screen printing is changed by automation recently, could print more exactly. However, must suffer great many trial and error to have still gotten perfect result. By the way, at this step, fair time and money should be invested. Therefore, if search for optimum condition in early time visualizing screen printing process using simulator program before progress printing, is judged that may be correct and gets printing result efficiently. In this paper, searched optimum printing speed and ink viscosity using FLOW-3D program. Also, the result could confirm truth that is agreeing almost with experiment contents. Through this, is thought that may expect extension of screen printing wide application that vivify advantage of screen print if use simulation program.

• The Journal of the Korea institute of electronic communication sciences
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• v.2 no.4
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• pp.199-202
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• 2007

In this paper, we examined the operating principle of a passive tag antenna for RFID system in UHF band. Based on the study, we proposed a novel RFID tag antenna which adopts the inductively coupled feeding structure to match antenna impedance to a capacitively loaded commercial tag chip. The proposed tag antenna consists of microstrip lines on a thin PET substrate for low-cost fabrication. The detail structure of the tag antenna were optimized using a full electromagnetic wave simulator of IE3D in conjunction with a Pareto genetic algorithm, and the size of the tag antenna can be reduced up to kr=0.27(2 cm2). We built some sample antennas and measured the antenna characteristics such as a return loss, an efficiency, and radiation patterns. The readable range of the tag antenna with a commercial RFID system showed about 1 to 3 m.

• Journal of Navigation and Port Research
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• v.28 no.1
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• pp.31-36
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• 2004

In this paper, the characteristics of an inverted-F antenna for the 2.4GHz(ISM) Bluetooth system have been analysed in terms of the variation of design parameters. The antenna can be integrated on printed circuit board, and the characteristics in terms of the variation of the gap between feed line and shorting stub, gap between antenna's leg and ground plane, antenna leg's width, substrate's height and dielectric constant are analysed By using these characterization plot of design parameter, the tuning techniques are proposed to design optimum antenna. The designed antenna has 6.3%(150MHz) frequency bandwidth for VSWR under 1.5, and 3dBi gain.

• Proceedings of the IEEK Conference
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• 2000.11b
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• pp.341-344
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• 2000

Several new via structures in printed circuit boards are proposed, fabricated and characterized in RF regime. The new structure with a larger inductance component in the bottom layer shows 3㏈ improvement over the conventional structure. The ADS simulation with model parameters extracted from 3D fie]d solver matches with the characterization of these vias

• 한국신재생에너지학회:학술대회논문집
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• 2011.05a
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• pp.113.1-113.1
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• 2011

PEMS (printed electro-mechanical system) is fabricated by means of various printing technologies. Passive and active compo-nents in 2D or 3D such as conducting lines, resistors, capacitors, inductors and TFT(Thin Film Transistor), which are printed withfunctional materials, can be classified in this category. And the issue of PEMS is applied to a R2R process in the manu-facturing process. In many electro-devices, the vacuum process is used as the manufacturing process. However, the vacuum process has a problem, it is difficult to apply to a continuous process such as a R2R(roll to roll) printing process. In this paper, we propose an ESD (electro static deposition) printing process has been used to apply an organic solar cell of thin film forming. ESD is a method of liquid atomization by electrical forces, an electrostatic atomizer sprays micro-drops from the solution injected into the capillary with electrostatic force generated by electric potential of about several tens kV. ESD method is usable in the thin film coating process of organic materials and continuous process as a R2R manufacturing process. Therefore, we experiment the thin films forming of PEDOT:PSS layer and active layer which consist of the P3HT:PCBM. The organic solar cell based on a P3HT/PCBM active layer and a PEDOT:PSS electron blocking layer prepared from ESD method shows solar-to-electrical conversion efficiency of 1.42% at AM 1.5G 1sun light illumination, while 1.86% efficiency is observed when the ESD deposition of P3HT/PCBM is performed on a spin-coated PEDOT:PSS layer.