• Title/Summary/Keyword: Li-Hak

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3D Visualization of Knee MRI using VTK (VTK를 이용한 무릎 MRI의 3차원 가시화)

  • Li, Sheng-Zhe;Cui, Xue-Nan;Hong, Seong-Wook;June, Chittoo;Kim, Hak-Il
    • Proceedings of the Korean Information Science Society Conference
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    • 2010.06b
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    • pp.283-288
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    • 2010
  • 본 논문은 VTK를 이용한 3차원 무릎 MRI 가시화에 대한 프로그램 기술을 제안한다. 기존의 많은 연구에서는 VTK를 사용하여 의료영상에 대한 3차원 가시화 프로그램을 제안하였으나 골관절염 진단을 목표로 한 무릎 3차원 가시화 방법은 아직 많이 제안되지 않고 있다. 본 논문에서는 볼륨렌더링(Volume redering) 기술과 다각형렌더링(Polygonal rendering)기술을 융합하여 무릎 및 연골을 효과적으로 가시화 할 수 있는 방법을 제안한다. 프로그램은 사용자 상호작용이 가능하고 VTK를 이용한 GPU기반의 프로세싱을 기반으로 하기 때문에 실시간 렌더링이 가능하다. 실험결과로부터 제안한 3차원 가시화 기술은 연골과 무릎의 관계를 직관적으로 표현할 수 있어 골관절염 조기진단에 유용하게 사용될 것으로 기대한다.

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Fatigue Crack Growth Simulation of Arbitrarily Shaped Three Dimensional Cracks Using Finite Element Alternating Method (유한요소 교호법을 이용한 임의 형상의 삼차원 균열의 피로균열 성장 해석)

  • Park, Jai-Hak;Kim, Tae-Soon
    • Journal of the Korean Society of Safety
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    • v.21 no.1 s.73
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    • pp.15-20
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    • 2006
  • The finite element alternating method is a convenient and efficient method to analyze three-dimensional cracks embedded in an infinite or a finite body because the method has the property that the uncracked body and cracks can be modeled independently. In this paper the method was applied for fatigue crack growth simulation. A surface crack in a cylinder was considered as an initial crack and the crack configurations and stress intensity factors during the crack growth were obtained. In this paper the finite element alternating method proposed by Nikishkov, Park and Atluri was used after modification. In the method, as the required solution for a crack in an infinite body, the symmetric Galerkin boundary element method formulated by Li and Mear was used. And a crack was modeled as distribution of displacement discontinuities, and the governing equation was formulated as singularity-reduced integral equations.

Origin and Meanings of Shape of Vital Gate(命門) in Yixuerunmen(醫學入門) (『의학입문(醫學入門)』 명문(命門) 형상(形狀)의 유래와 의의)

  • Jo, Hak-jun
    • Journal of Korean Medical classics
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    • v.28 no.4
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    • pp.79-97
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    • 2015
  • Objectives : To research origin of the shape of vital gate(命門) in Yixuerunmen makes us understand more exactly what the author, Li Chan(李梴) thought vital gate shaped. Methods : It's shape described in his book was compared with pictures portraying it in Hua Tuo Xuan Men Nei Zhao Tu(華陀玄門內照圖), one of references of his book. Results : He reasonably modified its passing track, while explaining it according to the paintings in Hua Tuo Xuan Men Nei Zhao Tu. Vital gate, as he thought, was not an real organ like the other five viscera, but a cord or a tube similar to blood vessels. He believed its cord had long connections from pericardium to terminal of urethra, which went through pericardium upward, right kidney downward, right around terminal rectum down-frontward, and urethra in parallel outward. Conclusions : He had consistent understandings for vital gate to penetrate several different viewpoints, as based on pictures in Hua Tuo Xuan Men Nei Zhao Tu.

An Effective Pre-refresh Mechanism for Mobile Handhold Device′s Embedded Web Browser

  • Li, Hua-Qiang;Kim, Young-Hak
    • Proceedings of the Korean Information Science Society Conference
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    • 2002.10e
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    • pp.151-153
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    • 2002
  • Mobile handhold devices such as PDA(Personal Digital Assistant) and Cellular Phone are more and more popular for personal web surfing. But today, most mobile handheld devices have relatively poor web browsing capability because of the small bandwidth of wireless connection, the small speed of CPU, the small capacity of RAM and Flash ROM, the small display size of LCD and the short lifecycle of battery. Users have to endure bigger communication latency than Desk PC's one because of these factors. In this paper, we propose an effective pre-refresh mechanism for handheld device's embedded web browser so as to make user's web surfing faster. The experiment was done using the simulator designed by ourselves and the experiment result demonstrates the proposed mechanism has a good performance to make web surfing faster.

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A Study on the Measurement of the Concentration and the Size Distribution of Inclusions in the Molten Aluminum (용융 알루미늄내에서 개재물의 크기분포 및 농도측정에 관한 연구)

  • An, Jeong;Moon, Kwang-Ho;Lee, Kwang-Hak
    • Journal of Korea Foundry Society
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    • v.14 no.1
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    • pp.62-74
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    • 1994
  • The concentration and particle size distribution of non-metallic inclusions which suspended in the molten aluminum at $700^{\circ}C$ were measured by using LiMCA apparatus. The result revealed that the number of inclusions increased with increasing the applied current or decreasing the orifice diameter, while decreased with increasing the purity of aluminum. And also, it was found that the number of inclusions increased with increasing the amount of boron added to molten aluminum. This was found to be attributed to the formation of the inclusions of TiB and $V_3B_2$. It was investigated that the average concentration of inclusions in a constant volume of 20ml of molten aluminum was increased in the order of pure molten aluminum, molten aluminum containing 20ppm of boron and molten aluminum used repeatly in the experimental casting in this study.

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Determination of Bovine Serum Albumin by Its Enhancement Effect of Nile Blue Fluorescence

  • Lee, Sang-Hak;Suh, Jung-Kee;Li, Ming
    • Bulletin of the Korean Chemical Society
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    • v.24 no.1
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    • pp.45-48
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    • 2003
  • A novel fluorimetric method has been developed for the determination of microgram quantities of bovine serum albumin (BSA) based on its enhancement effect of Nile Blue fluorescence at 670 nm, caused by binding of Nile Blue to BSA to produce a stable water soluble complex. The binding constant of micromole Nile Blue-BSA complex was estimated by Scatchard plot method. Under the optimal conditions, the increased fluorescence intensity was linearly related to BSA concentration in the range of 0.5-12.0 ㎍/mL. The detection limit was 0.2 ㎍/mL, and the relative standard deviation of six replicate measurements was 1.4% for 10.0 ㎍/mL BSA. There was little interference from amino acids, sugars and most of metal ions.

The Electrical Properties of OLED by surface Etching methode of ITO (ITO 표면 처리방법에 따른 OLED의 전기적 특성)

  • Yang, Myoung-Hak;Ki, Hyun-Chul;Min, Yong-Ki;Hong, Kyung-Jin
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2008.06a
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    • pp.455-456
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    • 2008
  • In this study, we report that an electrical properties of OLEDs was investigated by the surface etching method of ITO Layer. The electrical properties of OLEDs was measured by IVL and optical properties by EL spectrum. The fundamental structure of OLEDs was ITO anode/TPD(400$\breve{A}$)/$Alq_3(600\breve{A})$/LiF(5$\breve{A}$)/Al(1200$\breve{A}$) cathode. The threshold voltage was low value according to the low resistance of surface. The luminance was increased by decreased surface resistance.

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The Electrical and Optical Properties of OLED by Various Cathode Layer (이중 음극층에 따른 OLED의 전기적 및 광학적 특성)

  • Yang, Myoung-Hak;Ki, Hyun-Chul;Kim, Sang-Ki;Cho, Jae-Chul;Hong, Kyung-Jin
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2008.06a
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    • pp.421-422
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    • 2008
  • The electrical properties of OLEDs was investigated by the various cathode layer. It was measured by IVL for electrical properties and optical properties by EL spectrum. The structure of OLEDs was ITO/TPD(400$\AA$)/$Alq_3$(600$\AA$)/LiF(5$\AA$)/various cathode layer. The threshold voltage was increased by the deposited Au layer. The luminance was decreased by deposited Au layer.

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The Development and Experimental Evaluation of 100kVA Unified Power Quality Conditioner interconnected to the Li-Battery System (리튬 배터리를 연계한 100kVA UPQC 개발 및 성능시험)

  • Lee, Hak-Ju;Chae, Woo-Kyu;Park, Jung-Sung;Sohn, Jin-Man;Choi, Eun-Sik
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.26 no.10
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    • pp.102-110
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    • 2012
  • This paper propose the advanced topology of UPQC, its DC link is connected with Lithium battery, to compensate the momentary interruptions. The proposed system can be operated as UPS mode using the parallel inverter, which control the charge or discharge of battery, in case of the interruption. We dvelop 100kVA UPQC using the proposed topology to rise the power quality and the reliability of Microgrid. We verify its usefulness through voltage compensation test, UPS operation test and etc. using Microgrid test facility.

The Properties of PLED by Pre-treatment (Plasma and heat treatment) on ITO surface (ITO 표면 전처리에 따른 PLED 소자의 특성 연구)

  • Gong, Su-Cheol;Sin, Sang-Bae;Sin, Ik-Seop;Yu, Byeong-Cheol;Lee, Hak-Min;Jeon, Hyeong-Tak;Park, Hyeong-Ho;Jang, Ho-Jeong
    • Proceedings of the Korean Institute of Surface Engineering Conference
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    • 2007.11a
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    • pp.89-90
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    • 2007
  • 본 연구에서는 ITO/PEDOT:PSS/PFO-poss/LiF/Al 구조를 갖는 고분자 유기발광다이오드(PLED)를 제작하여 ITO 투명 전도막의 전처리 효과가 유기발광 다이오드의 특성에 미치는 영향에 대하여 조사하였다. 최적의 전처리 조건을 찾기 위하여 다양한 플라즈마 처리 조건에 다른 ITO 투명전도막의 표면형상의 변화와 전기적 특성을 관찰하였다. 또한 ITO 투명전도막에 플라즈마 처리와 열처리를 실시하여 PLED 소자를 제작하고 전기 광학적 특성을 조사하여 ITO 투명 전도막의 전처리가 소자의 특성에 미치는 영향을 조사하였다.

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