• Title/Summary/Keyword: Sidewall

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Sound Insulation Performance of the Side Layered Panels in the Next Generation High Speed Train (차세대 고속철도 차량 측면 적층재의 차음성능)

  • Lee, Joong-Hyeok;Lee, Ho-Jin;Park, In-Seok;Kim, Seock-Hyun
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2011.10a
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    • pp.457-462
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    • 2011
  • The sidewall of the HEMU-400x consists of two parts. One is the multi-layered structure including aluminium extruded panel and the other is the double glazed window. When the train runs in a tunnel, the equivalent sound insulation performance of the side wall significantly influences the internal noise levels. In aspect of the sound insulation strategy, it is important to make two parts have similar performance. In this study, the intensity sound transmission loss (ITL) is measured on the specimens of the two parts. Mass law deviation (MLD) is considered in order to compare the sound insulation performance of the two parts in respect of the weight. Contribution of each part to the sound insulation is analyzed and the sound insulation strategy is investigated to reduce the interior noise.

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Direct Numerical Simulation of Low-Reynolds-Number Turbulent Flows in an Open-Channel: An Analysis of Turbulence Anisotropy (저 레이놀즈 수 개수로 난류흐름의 직접수치모의: 난류의 비등방성 해석)

  • Joung, Younghoon;Choi, Sung-Uk;Choi, Jung-Il
    • Proceedings of the Korea Water Resources Association Conference
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    • 2004.05b
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    • pp.376-380
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    • 2004
  • 측벽이 존재하는 개수로 난류흐름에 대한 DNS 자료를 이용하여 난류의 비등방성을 해석하였다. 측벽의 2등분선(sidewall bisector)에서 난류강도의 분포를 통해 바닥과 자유수면에서의 비등방성을 분석하고, AIM을 도입하여 흐름장 전반에 걸쳐 세부적인 비등방성 해석을 수행하였다. 측벽의 2등분선에서의 난류강도의 분포를 통해 바닥과 자유수면 근처에서 난류강도가 강한 비등방성을 갖는 것을 볼 수 있었다. 또한 3개의 다른 영역에서 AIM의 도입을 통해 측벽이나 바닥근처에서는 난류의 비등방성이 구형 관수로 흐름과 유사한 것으로 나타났으나, 개수로 난류흐름의 주된 특성이 velocity-dip phenomena가 존재하는 영역에서는 구형 관수로 흐름과는 달리 천이영역이 존재한다는 것을 알 수 있었다.

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Development of Artificial Skin from Chitosan Derivatives

  • Yong-Don Won;Chang-Kook Lee;Beung-Ho Ryu
    • Journal of Life Science
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    • v.9 no.1
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    • pp.17-21
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    • 1999
  • Chitosan derivitives, a sulfated N-acetylchitosan was synthesized, and artificial skin of sulfated N-acetylchitosan and N-carboxyl butyl chitosan were investigated. Sulfated derivatives of chitosan were analyzed by {TEX}${13}^C${/TEX}-NMR and the structure on N-acetyl chitosan 3,6-O-disulfate were confirmed. Rabbits underwent a midline laparotomy followed either by a bilateral peritoneal sidewall abraison(3.0×1.5cm). The injured surface was then covered with 0.2mm thick sulfated N-acetyl chitosan membrane. Sulfated N-acetyl chitosan membrane was found to reduce postsurgical bleeding after abraison of peritoneal surface treated with sulfated N-acetyl chitosan membrane. Sulfated N-acetyl chitosan implanted rabbit showed quick wound healing than N-carboxybutyl chitosan. With a sterilization procedure of chemical sterilization, sulfated N-acetyl chitosan seem to be better substitutes than N-carboxybutyl chitosan.

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A Study of Three Dimensional Ion Implantation Simulator (3차원 이온 주입 시뮬레이터 개발에 관한 연구)

  • 송재복;원태영
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1996.11a
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    • pp.93-96
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    • 1996
  • We developed three dimensional Monte carlo ion implantation simulator which simulate distributions of impurities under the ion implantation on the tilted multi-layered layer. Our simulation reveals three dimensional shadow effect and sidewall scattering effect due to the geometrical shapes. For the evaluation of the developed three dimensional Monte carlo ion implantation simulator, calculations with 100,000 ions have been performed for the island and hole structures with a thin oxide of 100$\AA$ and nitride of 2000$\AA$. The simulation results showed that the distribution of ion decreases near the conner of the hole structure covered with a nitride layer and increases near the conner for the island structure open to oxide. Moreover, three dimensional distributions of ions were obtained with varying incident energy, tilt and rotation angle, mask depth and three-dimensional structure geometry.

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Characteristics of the 2-D SSIMT using a CMOS Process (CMOS 공정을 이용한 2차원 SSIMT의 특성)

  • Song, Youn-Gui;Ryu, Ji-Goo
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.20 no.8
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    • pp.697-700
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    • 2007
  • A novel 2-Dimensional Suppressed Sidewall Injection Magnetotransistor (SSIMT) with high linearity has been fabricated on the standard CMOS technology and experimentally verified. The novel 2-Dimensional SSIMT overcomes the restriction of the standard CMOS technology. Experimental results of the fabricated 2-Dimensional SSIMT show that the variation of each collector output currents are extremely linear as a function of magnetic field from -200mT to 200mT at $I_B = 1 mA,\;V_{CE} = 5 V\;and\;V_{SE} = 5 V$. The relative sensitivity shows up to 13 %/T. The measured nonlinearity of the fabricated device is about 0.9%.

A Study on Cleaning Processes for Ti/TiN Scales on Semiconductor Equipment Parts (반도체 장비 부품의 Ti/TiN 흡착물 세정 공정 연구)

  • 유정주;배규식
    • Journal of the Semiconductor & Display Technology
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    • v.3 no.2
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    • pp.11-15
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    • 2004
  • Scales, accumulated on some parts of semiconductor equipments such as sputters and CVD during the device fabrication processes, often lower the lifetime of the equipments and production yields. Thus, many equipment parts have be cleaned regularly. In this study, an attempt to establish an effective process to remove scales on the sidewall of collimators located inside the chamber of the sputter was made. The EDX analysis revealed that the scales were composed of Ti and TiN with the columnar structure. Through the trial-and-error experiments, it was found that the etching in the $HNO_3$:$H_2SO_4$:$H_2O$=4:2:4 solution for 5.5 hrs at $67^{\circ}C$, after the oxide removal in the HF solution, and the heat-treatment at $700^{\circ}C$ for 1 min., was the most effective process for the scale removal.

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The Effects of Various Apodization Functions on the Filtering Characteristics of the Grating-Assisted SOI Strip Waveguides

  • Karimi, Azadeh;Emami, Farzin;Nozhat, Najmeh
    • Journal of the Optical Society of Korea
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    • v.18 no.2
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    • pp.101-109
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    • 2014
  • In this paper, four apodization functions are proposed for silicon-on-insulator (SOI) strip waveguides with sidewall-corrugated gratings. The effects of apodization functions on the full width at half maximum (FWHM), the side-lobe level, and the reflectivity of the reflection spectrum are studied using the coupled-mode theory (CMT) and the transfer-matrix method (TMM). The results show that applying proposed apodization functions creates very good filtering characteristics. Among investigated apodized waveguides, the apodization functions of Polynomial and z-power have the best performance in reducing side-lobes, where the side-lobe oscillations are entirely removed. Four functions are also used for precise adjustment of the bandwidth. Simulation results show that the minimum and maximum values of the FWHM are 0.74 nm and 8.48 nm respectively. In some investigated functions, changing the apodization parameters decreases the reflectivity which is compensated by increasing the grating length.

Transparent Plasma Display using Transparent Glass Barrier Ribs

  • Lee, Sung-Min;Kim, Seung-Hun;Oh, Seung-Hwa;Shin, Bhum-Jae;Choi, Kyung-Cheol
    • 한국정보디스플레이학회:학술대회논문집
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    • 2009.10a
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    • pp.339-341
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    • 2009
  • A transparent plasma display was developed using transparent glass barrier ribs. Glass barrier ribs were fabricated via a wet etching process. Glass barrier ribs created using a top and bottom etching process showed better transparency compared to those created through only a top etching process. A see-through phosphor layer was obtained by coating the sidewall of the barrier ribs with a conventional opaque phosphor. A fabricated prototype of a transparent plasma display was clear enough to see the background beyond the panel and was well operated by a conventional driving scheme. The maximum luminance was 1150 cd/$m^2$ and the maximum luminous efficacy was 1.35 lm/W in a Ne+13.5%Xe gas-mixture and green cells.

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Fabrication of 2-D Microwell Arrays for Micro ELISA System (초소형 면역 분석기용 이차원적 배열형 마이크로 우물 제작)

  • Lee, Kook-Nyung;Ahn, Si-Hong;Park, Jae-Hyung;Kim, Yong-Kweon
    • Proceedings of the KIEE Conference
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    • 1998.07g
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    • pp.2556-2558
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    • 1998
  • 2-D microwell arrays for micro ELISA (Enzyme-Linked Immuno Solvent Assay) system were fabricated using micromachining technology. The materials for the bottom plate, top plate and sidewall of the microwell were used a #7740 glass, gold and silicon respectively considering bio-compatibility and easy fabrication. Cylindrical or groove shape microwells, which have about $100{\mu}m$ depth and $50{\sim}500{\mu}m$ diameter or width, were arrayed. The fabricated microwell array can be applied to the essential part of a biochip when surface modification is made to immobilize cells or biomolecules on the microwell bottom.

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Speckle Defect by Dark Leakage Current in Nitride Stringer at the Edge of Shallow Trench Isolation for CMOS Image Sensors

  • Jeong, Woo-Yang;Yi, Keun-Man
    • Transactions on Electrical and Electronic Materials
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    • v.10 no.6
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    • pp.189-192
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    • 2009
  • The leakage current in a CMOS image sensor (CIS) can have various origins. Leakage current investigations have focused on such things as cobalt-salicide, source and drain scheme, and shallow trench isolation (STI) profile. However, there have been few papers examining the effects on leakage current of nitride stringers that are formed by gate sidewall etching. So this study reports the results of a series of experiments on the effects of a nitride stringer on real display images. Different step heights were fabricated during a STI chemical mechanical polishing process to form different nitride stringer sizes, arsenic and boron were implanted in each fabricated photodiode, and the doping density profiles were analyzed. Electrons that moved onto the silicon surface caused the dark leakage current, which in turn brought up the speckle defect on the display image in the CIS.