• Title/Summary/Keyword: Resonance structures

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New PDP cell designs for high luminous efficiency and radiation transport model in PDP

  • Yang, Sung-Soo;Shin, Seung-Won;Kim, Hyun-Chul;Lee, Jae-Koo
    • 한국정보디스플레이학회:학술대회논문집
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    • 2002.08a
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    • pp.590-593
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    • 2002
  • Using two- and three-dimensional fluid simulation codes, we have suggested several new plasma display panel (PDP) cell structures that have high luminous efficiency compared with conventional structure. To improve the luminance and discharge efficiency, we utilize long discharge path, lower electric field region, and reduction of power consumption by adding one auxiliary electrode or reducing the electrode area. Consequently, luminous efficiency increases about 1.8 times. Furthermore for the resonance radiation trapping effect in PDP system, we have described a self-consistent radiation transport model coupled with fluid simulation using modified Holstein's equation.

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The Principles and Metrical Applications of Immunocsensors (면역센서의 원리와 의학적 응용)

  • 김의락;백세환
    • KSBB Journal
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    • v.17 no.2
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    • pp.121-136
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    • 2002
  • Immunosensors are of great interest because of their potential utility as specific, simple, label-free, direct detection means and provision of reduction in size, cost and time of analysis comparing with conventional immunoassay. In the last two decades, many reports have been published on the use of immunosensors for a wide range of applications to clinical diagnostics, pharmaceutical chemistry, environmental monitoring, biotechnology and food industries. There are also numerous transduction techniques developed such as electrochemical techniques, piezoelectric crystal, and surface plasmon resonance receiving much attention for the direct monitoring of immune reactions at solid surfaces. In this article, the principles, characteristics, structures, fonctions and clinical applications of immunosensors were reviewed

The Study on the Improvement on Damping Ratio of Dynamic Absorber using Silicon Oil (실리콘 오일을 이용한 동흡진기 감쇠 성능 향상에 대한 연구)

  • Kwak, Y.S.;Kim, W.H.;Joo, W.H.
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2011.04a
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    • pp.113-118
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    • 2011
  • Many kinds of dynamic absorbers have been used to reduce the vibration of machineries and structures. In the typical ones, however low damping capacity, durability and limited install condition restrict their application. In this study, high damped dynamic absorber was proposed for diesel generator set. Developed absorber is composed with mass and coil springs. Silicone oil was filled inside the narrow gap between mass and casing. Viscous damping of silicon oil act as additional damping so that proposed dynamic absorber is suitable for D/G set which have adjacent resonance frequency to operation speed. The performance of the dynamic absorber was confirmed through the actual test on diesel engine generator set.

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Compounds from the Aerial Parts of Aceriphyllum rossii and Their Cytotoxic Activity

  • Tran, Thi Thu Trang;Nguyen, Thi Yen;Tran, Manh Hung;Weon, Kwon-Yeon;Woo, Mi Hee;Min, Byung Sun
    • Natural Product Sciences
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    • v.20 no.3
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    • pp.146-151
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    • 2014
  • The purification of the MeOH extracts from the aerial parts of Aceriphyllum rossii Engler (Saxifragaceae) using column chromatography furnished fourteen compounds (1 - 14). The chemical structures of the isolated compounds were determined using mainly nuclear magnetic resonance spectra and mass spectrometry. All the isolated compounds were tested for their cytotoxic activity against LH-60, MCF-7 and HeLa cancer cells in vitro using a MTT assay method. Compounds possessing an olean-triterpenoid skeleton entirely exhibit dose dependent cytotoxic activity. These findings partially confirmed the anticancer effect of this medicinal plant, suggesting a further study on the anticancer potential of the triterpenoid structure in compounds from this plant.

Evaluation of Diesel Engine Structural Vibration Using Phase Vector Sum (Phase vector sum을 이용한 디젤엔진 구조진동의 평가)

  • 이수목;김관영
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2003.11a
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    • pp.383-388
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    • 2003
  • As an effective way of response evaluation in structural vibration analysis, the phase vector sum(PVS) method used in shaft torsional vibration analysis is introduced. Basic relation of PVS applicable to structural problem is derived and applied to Diesel engine structures. Concepts of forced phase vector sum (FPVS) and significance level (SL) are proposed to visualize the correlation between excitation orders and vibration modes in the SL map. The maximum responses and SL are compared and reviewed to confirm the validity of the method. It is regarded FPVS is adequate to newly evaluate the structural vibration based on excitation information.

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Structural Analysis of Black Common Bean (Phaseolus vulgaris L.) Anthocyanins

  • Choung, Myoung-Gun
    • Food Science and Biotechnology
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    • v.14 no.5
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    • pp.672-675
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    • 2005
  • Two anthocyanins were isolated from 1% HCl-20% methanol extracts of KG 97287 black common bean (Phaseolus vulgaris L.) using semipreparative, high-performance liquid chromatography (HPLC). The anthocyanins were identified using a combination of LC/ES-mass spectrometry (MS) and spectroscopic methods of UV-Vis, $^1H-$ and $^{13}C-$ nuclear magnetic resonance (NMR). The chemical structures of these two anthocyanins were elucidated as delphinidin 3-glucoside and petunidin 3-glucoside and their contents in KG 97287 black common bean seed coats were determined to be $2.614{\pm}0.11$ and $0.167{\pm}0.01\;mg/g$, respectively. These contents were lower than reported internationally and we recommend the introduction into Korea of high anthocyanin varieties of black common bean.

A Numerical Analysis on the Vibration Characteristics of Rotating Composite Blades (회전하는 복합재료 블레이드의 진동특성에 대한 수치해석)

  • Kee, Young-Jung;Song, Keun-Woong;Kim, Deog-Kwan;Shim, Jeong-Wook
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2006.05a
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    • pp.300-303
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    • 2006
  • The rotor blade of a helicopter is the key structural units and provides three components such as vertical lifting force, horizontal propulsive force and control force. With advancements in aerospace technology, composite materials have been widely used in lightweight structures. In addition, composites show great potential on the design of rotor blades due to the advantages of strength, durability and weight of the materials. In the operational condition of a helicopter, it is required the vibration characteristics of the rotating blades for avoiding resonance and analysis of efficient performance prediction et al. In this study, the CAMRAD-II is used for analyzing the vibration characteristics of rotating composite blades. The effects of rotating speed and collective angles are investigated. Also, the numerical results are compared with experimental data.

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Computation of Radar Cross Section from Arbitrarily Shaped Composite Objects Using Combined Field Integral Equation (결합 적분방정식을 이용한 임의 형태 복합구조의 레이더 단면적 산출)

  • 한상호;정백호;윤희상
    • The Transactions of the Korean Institute of Electrical Engineers C
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    • v.53 no.1
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    • pp.41-46
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    • 2004
  • In this paper, we present a new combined field integral equation (CFIE) formulation for the analysis of electromagnetic scattering from arbitrarily shaped three-dimensional perfectly conducting and piecewise homogeneous dielectric composite body. The conducting/dielectric structures are approximated by planar triangular patches, which have the ability to conform to any geometrical surface. The surface covering the conducting body is replaced by an equivalent surface electric current and the surface of the dielectric by equivalent electric and magnetic currents. The all equivalent currents are approximated in terms of RWG (Rao, Wilton, Glisson) functions. The objective of this paper is to illustrate that the CFIE is a valid methodology in removing defects, which occur at a frequency corresponding to an internal resonance of the structure. Numerical results are presented and compared with solutions obtained using other formulations.

Sliding Conditions at the Interface between Soil and Underground Structure (지반과 지하구조물 경계의 미끄러짐 조건에 관한 연구)

  • 김대상
    • Journal of the Earthquake Engineering Society of Korea
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    • v.6 no.1
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    • pp.7-11
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    • 2002
  • By focusing on the resonant vibration mode of soil-underground structure system, this paper obtained dynamic soil stiffness and easy sliding conditions at the interface between soil and underground structure. Multi-step method is employed to isolate two primary causes of soil-structure interaction. Mohr-Coulomb criterion is used to determine the threshold level of the sliding. To find out the conditions the interface slides easily, parametric studies are performed about the factors governing sliding, which are the size and location of underground structures, ground condition, the configuration of surface deposit and interface friction coefficients.

Preparation and Optical Characterization of Photonic Crystal Smart Dust Encoded with Reflection Resonance (반사공명으로 인코딩된 광결정 스마트 먼지의 제조방법 및 광학적 특징)

  • Lee, Boyeon;Hwang, Minwoo;Cho, Hyun;Kim, Hee-Cheol;Han, Jungmin
    • Journal of Integrative Natural Science
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    • v.3 no.2
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    • pp.84-88
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    • 2010
  • Photonic crystals containing rugate structures from a single crystalline silicon wafer was obtained by using a sinoidal alternating current during an electrochemical etch procedure. Photonic crystals were isolated from the silicon substrate by applying an electropolishing current and were then made into particles by using an ultrasonic fracture in an ethanol solution to give a smart dust. Smart dusts exhibited their unique nanostructures and optical characteristics. They exhibited sharp photonic band gaps in the optical reflectivity spectrum. The size of smart dust obtained was in the range of 10-20 nm.