• 제목/요약/키워드: and resonance

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Structural Studies on IRES 4-2 Domain of Foot-and-mouth Disease Virus

  • Kim, Young-Mee;Yoo, Jun-Seok;Cheong, Hae-Kap;Lee, Chul-Hyun;Cheong, Chae-Joon
    • 한국자기공명학회논문지
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    • 제7권2호
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    • pp.89-97
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    • 2003
  • Foot-and-mouth disease virus (FMDV) belongs to the aphthovirus genus within the picornavirus which has a single copy of a positive sense RNA. The translation initiation process of FMDV occurs by a cap-independent mechanism directed by a highly structured element (∼435 nt) termed an internal ribosome entry site (IRES). We have designed and prepared FMDV 4-2 RNA (28nt) by in vitro transcription. The 2D NMR data revealed that FMDV 4-2 IRES domain RNA has a flexible loop and bulge conformation. In further study, we need to make an isotope labeled RNA sample and conduct 3D NMR experiments to completely determine the 3D structure. This study may establish a new drug design strategy to treat foot-and mouth disease.

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홀로그래피 간섭계를 이용한 복합적층판의 결함측정 (Nondestructive Inspection Method of Composite Laminated Plates by Holographic Interferometry)

  • 김석중;김재형;박현철
    • 대한기계학회논문집
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    • 제18권12호
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    • pp.3202-3218
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    • 1994
  • Mode shapes and natural frequencies of vibrating laminated composite plates are taken using real-time and time-average holographic interferometry. Debonds and delamination in the laminated plates are measured nondestructively. During holographic testing of composite plates, it has been found that the conditions for the local resonance in debonds are strongly dependent on the frequency of excitation. A membrane resonance model was proposed to describe this behavior. Relations between characteristic length according to the size, shape of debonds and membrane resonance frequency are presented. Several experiments were performed to verify the membrane resonance model. The agreements between the predicted excitation frequency and the observed resonance frequency are good. The experimental results show that higher stresses and strains due to local resonance lead to the debond detection.

Breast Magnetic Resonance Image (MRI) Guideline: Breast Imaging Study Group of Korean Society of Magnetic Resonance in Medicine Recommendations

  • Choi, Seon Hyeong;Kang, Bong Joo;Jung, Seung Eun
    • Investigative Magnetic Resonance Imaging
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    • 제22권4호
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    • pp.205-208
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    • 2018
  • The purpose of this study is to establish an appropriate protocol for breast magnetic resonance imaging (MRI) in the discipline of image quality standards. The intention of the protocol is to increase effectiveness of medical image information exchange involved in construction, activation, and exchange of clinical information for healthcare.

Anti-windup 보상기의 점프공진에 관한 연구 (Jump resonance in anti-windup compensator for systems with saturating actuators)

  • 박영진;장원욱
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1992년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 19-21 Oct. 1992
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    • pp.1060-1066
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    • 1992
  • One of the undesirable nonlinear phenomenon called 'wind up' occours when the integrator in the controller and the saturated actuator interact. Large overshoot, slow response, instability, limit cycle and jump resonance are the characteristics of wind up phenomenon. Several 'anti-windup' compensators have been developed to prevent some of the aforementioned nonlinear characteristics such as instabilituy and limit cycle, but none has studied the effect of antiwindup compensator on the jump resonance. In this paper, we developed an analyitcal method to design the compensator to prevent not only limit cycle but also jump resonance. An illustrative example is included to show the compensator eliminates jump resonance of effectively.

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마이크로기계 공진 센서의 유체-구조물 상호 작용 해석 (Fluid-structure interaction analysis of micromechanical resonance sensor)

  • 강인구;신윤혁;임홍재;임시형
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2009년도 추계학술대회 논문집
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    • pp.309-313
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    • 2009
  • A micromechanical resonance sensor detects the resonance frequency shift due to mass or adsorption induced surface stress change during molecular adsorption or interaction on its surface. The resonance sensor is surrounded by gas or liquid solution during operation. To study the resonance shift phenomena depending on its surrounding environment, fluid-structure interaction of the resonance sensor has been analyzed for the different fluid environment and boundary conditions using finite element analysis.

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이중공진을 사용한 적층기판용 광대역 안테나 설계 (A Wide-band Multi-layer Antenna Design using Double Resonance)

  • 이국주;장미선;이정언;한명우;김문일
    • 전기학회논문지
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    • 제60권2호
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    • pp.431-434
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    • 2011
  • In this paper, bandwidth enhanced design of dielectric resonator antenna fabricated in multi-layer substrate is introduced. The proposed dielectric resonator antenna is operating with fundamental TE101 mode and higher-order TM111 mode. Each resonance frequency is dependent on resonator dimensions. As increasing the height of radiating aperture, the higher-order TM111 mode resonance frequency approach the fundamental TE101 mode resonance frequency and the antenna bandwidth increase by double resonance. Three different aperture height size antennas that operated at 7GHz are fabricated in FR4 multi-layer substrate. Measured 10 dB matching bandwidth is 8 percent for single resonace antenna and 18 percent for double resonance antenna.

대형석탄화력발전용 보일러 관군의 Anti-Noise Baffle 설치에 따른 음향공진 (Acoustic resonance by Inserting Anti-noise Baffle in the Tube Bank of Boiler of a Large Fossil Power Plant)

  • 방경보;김철홍
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2004년도 추계학술대회논문집
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    • pp.178-183
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    • 2004
  • This paper presents phenomena of vibration and noise due to acoustic resonance in tube bank of a large fossil power plant. The phenomena of acoustic resonance may arise when the vortex shedding frequency coincides with the acoustic natural frequency. In this system dominant frequency of vibration and noise was 37.5Hz. The $3^{rd}$ acoustic natural frequency calculated was 37.2 Hz. When the difference of vortex shedding frequency and acoustic natural frequency is within ${\pm}20%$, acoustic resonance could occur. If system is the state of acoustic resonance, vibration and noise become large. In order to prevent acoustic resonance, anti-noise baffle should be installed in the tube bank. In the case of installing baffle, we should consider the number of baffle and the effect of acoustic mode due to baffle extension length. To do this, we did acoustic mode analysis. After installing anti-noise baffle, acoustic resonance was disappeared and vibration magnitude and noise level was reduced dramatically.

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Experimental study on moonpool resonance of offshore floating structure

  • Yang, Seung-Ho;Kwon, Sun-Hong
    • International Journal of Naval Architecture and Ocean Engineering
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    • 제5권2호
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    • pp.313-323
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    • 2013
  • Offshore floating structures have so-called moonpool in the centre area for the purpose of drilling, installation of subsea structures, recovery of Remotely-Operated Vehicle (ROV) and divers. However, this vertical opening has an effect on the operating performance of floating offshore structure in the vicinity of moonpool resonance frequency; piston mode and sloshing mode. Experimental study based on model test was carried out. Moonpool resonance of floating offshore structure on fixed condition and motion free condition were investigated. And, the effect of cofferdam which is representative inner structure inside moonpool was examined. Model test results showed that Molin's theoretical formula can predict moonpool resonance on fixed condition quite accurately. However, motion free condition has higher resonance frequency when it is compared with that of motion fixed. The installation of cofferdam moves resonance frequency to higher region and also generates secondary resonance at lower frequency. Furthermore, it was found that cofferdam was the cause of generating waves in the longitudinal direction when the vessel was in beam sea.