• 제목/요약/키워드: Fine Tuning

검색결과 343건 처리시간 0.027초

Electromagnetic Modeling of Quasi-Square Open Metallic Ring Frequency Selective Surface Using Wave Concept Iterative Procedure

  • Titaouine, Mohammed;Raveu, Nathalie;Neto, Alfredo Gomes;Baudrand, Henri
    • ETRI Journal
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    • 제31권1호
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    • pp.77-79
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    • 2009
  • The wave concept iterative procedure (WCIP) is used to analyze a quasi-square open metallic ring frequency selective surface (FSS). The quasi-square open metallic ring FSS is dual-polarized. When the incident plane wave is polarized in a direction parallel to the FSS' coupled parallel strips, it shows two rejecting bands. Moreover, another rejecting band can be obtained if the source plane wave is perpendicularly polarized with respect to the FSS' coupled parallel strips. The three resonant frequencies are inversely proportional to the length of the FSS' coupled strips to provide an easy fine tuning of the FSS structure. The simulated results obtained using WCIP are compared to the measured results, and a good agreement is reported.

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w 변환법에 의한 전기 - 유압식 조속기를 가진 박용디젤기관의 속도제어 (The Speed Control of a Marine Diesel Engine with Electro Hydraulic Governor by using W Transformation Method)

  • 강창남;박진길
    • Journal of Advanced Marine Engineering and Technology
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    • 제21권2호
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    • pp.195-205
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    • 1997
  • The propulsion marine diesel engine have been widely applied with a mechanical- hydraulic governor to control the ship speed for long time. But it was recently very difficult for the mechani¬cal - hydraulic governor to control the speed of engine under the condition of low speed and low load because of jiggling by rough fluctuation of rotating torque and hunting by dead time of Desiel engnie The performance improvement of mechanical - hydraulic governor is required to solve these problems of control system. The electro - hydraulic governor using PID algorithm is provided to compensate the faults of mechanical- hydraulic governor. In this paper, in order to analyze the ship speed control system, the transfer function was converted from the z tansformation to w transformation. The influence of dead time changing by engine speed which induces hunting phenomena was investigated by Nichols chart of w plane. As a method of performance improvement of mechanical hydraulic governor, a Eletro - hydraulic governor shows that fine control results can be obtained through optimal parameter tuning of PID

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영상처리기법을 이용한 유기 EL용 ITO 코팅 유리의 표면결함 검출 알고리즘 개발 (Development of detection algorithm of the defected in the surface for ITO coated glass using image processing technique)

  • 김면희;박세홍;이상룡;김관수
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2003년도 춘계학술대회
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    • pp.1173-1178
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    • 2003
  • Recently, Organic EL(Electro Luminescence) is interested in Flat Panel Display(FPD) department of new generation. This paper describes a image processing algorithm for the scratch detecting for ITO coated glass. We use the logical level thresholding method for binarization of gray-scaled glass image. This method is useful to the algorithm for detecting scratch of ITO coated glass automatically without need of any prior information of manual fine tuning of parameters.

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화상처리를 이용한 ITO 코팅 유리의 결함검출기법 개발 (Deveopement of Scratch Detection Algorithm for ITO coated Glass using Image Processing Technique)

  • 김면희;배준영;이태영;안경철;이상룡
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2003년도 춘계학술대회 논문집
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    • pp.1275-1278
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    • 2003
  • This research describes a image-processing technique for the scratch detecting algorithm for ITO coated glass. The light emitter efficiency of Organic EL has a failing-off in quality due to many causes. One of the many causes was the defects of the surface in ITO coated glass. We use the logical level thresholding method for binarization of gray-scaled glass image. This method is useful to the algorithm for detecting scratch of ITO coated glass automatically without need of any prior information of manual fine tuning of parameters.

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Profibus 토큰 패싱 프로토콜 성능 모델에서의 전송 지연 특성 (Communication Delay Properties in Performance Model of Profibus Token Passing Protocol)

  • 이경창;김현희;이석
    • 제어로봇시스템학회논문지
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    • 제9권12호
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    • pp.1055-1064
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    • 2003
  • In many automated systems, such as manufacturing systems and process plants, a fieldbus is a very important component for the exchange of various and sometimes crucial information. Some of the information has a tendency to rapidly lose its value as time elapses after its creation. Such information or data is called real-time data that includes sensor values and control commands. In order to deliver these data in time, the fieldbus network should be tailored to have short delay with respect to the individual time limit of various data. Fine-tuning the network for a given traffic requires the knowledge on the relationship between the protocol parameters such as timer values and the performance measure such as network delay. This paper presents a mathematical performance model to calculate communication delays of the Profibus-FMS network when the timer value and the traffic characteristics are given.

An Identification Technique Based on Adaptive Radial Basis Function Network for an Electronic Odor Sensing System

  • Byun, Hyung-Gi
    • 센서학회지
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    • 제20권3호
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    • pp.151-155
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    • 2011
  • A variety of pattern recognition algorithms including neural networks may be applicable to the identification of odors. In this paper, an identification technique for an electronic odor sensing system applicable to wound state monitoring is presented. The performance of the radial basis function(RBF) network is highly dependent on the choice of centers and widths in basis function. For the fine tuning of centers and widths, those parameters are initialized by an ill-conditioned genetic fuzzy c-means algorithm, and the distribution of input patterns in the very first stage, the stochastic gradient(SG), is adapted. The adaptive RBF network with singular value decomposition(SVD), which provides additional adaptation capabilities to the RBF network, is used to process data from array-based gas sensors for early detection of wound infection in burn patients. The primary results indicate that infected patients can be distinguished from uninfected patients.

An Investigation into the PID Control for the Electro- Hydraulic Servo System of Skin Pass Mill

  • Lee, Jae-Cheon;Kim, Seong-Jin
    • International Journal of Precision Engineering and Manufacturing
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    • 제2권4호
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    • pp.47-53
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    • 2001
  • This study is to investigate the problem of the SPM(Skin Pass Mil7) system which is a finishing treatment of steel sheet. and to develop a PID control scheme to minimize process instability. An electrohydraulic servo system with conventional proportional controller used to regulate the force on the strip works inadequately to yield very undesirable transient responses at the moments welding parts of the strip conte into and pass through the rolls. Both linearized and nonlinear models of a typical SPM system ware simulated first by using Simulink. Then Ziegler-Nichols ultimate cycling method was used for an initial reference guide to tune PID gains, and further fine tuning was performed to get desirable response. The test result in the plant show that proposed PID control scheme successfully improves the process instability in a SPM system.

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주택경기 진단과 향후 과제

  • 한국주택협회
    • 주택과사람들
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    • 통권173호
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    • pp.24-32
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    • 2004
  • 2003년 10.29대책으로 주택가격이 하향세로 돌아섰으며 이후 계속되는 규제들로 주택 시장이 다소 위축되었다. 정부 정책이 수도권과 주택가격 안정에 집중된 결과, 규제를 덜 받는 토지와 개발계획이 발표된 충청권은 계속 가격이 올랐다. 막대한 부동자금이 시중에 존재하고 있는 상황에서 행정수도 이전 등 각종 개발계획들이 국지적 수요를 자극하고 가격상승을 부추기는 중이다. 반면 재건축 제한, 거래신고제, 부동산세 인상 등은 일시적으로 공급과 거래를 위축시키고 있다. 향후 주택시장은 정부정책이 시장 친화적 방향으로 조정되고 지속적인 주택공급이 이루어질 경우 하향 안정세가 계속될 가능성이 높다. 그러나 광일 유동성이 부동산으로 유입되면 상승세로 반전될 가능성이 있으므로 생산적 투자 확대, 장기 금융상품 개발 등으로 유동성을 흡수해야 한다. 정부는 주택시장 연착륙을 위해 정책 일관성을 유지하면서 시장이 제대로 작동될수 있도록 정책의(fine tuning)에 나서야 한다. 특히 재건축 규제를 완화하고 부동산 관련 세금을 경감하는 한편, 지속적인 시장 투명성 제고를 추진할 필요가 있다. 주택업체들은 자발적 구조조정과 기술개발로 승부를 걸어야 한다.

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나노입자 배열을 이용한 분자 검출 (Detection of Molecules using the Nanoparticle Arrays)

  • 하동한;김상훈;윤용주;박형주;윤완수
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2008년도 추계학술대회A
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    • pp.1617-1622
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    • 2008
  • We report a new molecular detection process which measures the changes in the plasmon resonance peaks of periodic Au nanoparticle arrays fabricated using the electron beam lithography. As the Au nanoparticle arrays are modified by the chemical reaction in solutions having various concentrations of a target molecule, both the position and intensity of the plasmon peak change in proportion to the concentration of the target molecule. We expect that the process developed in this work can be employed for fine tuning of the plasmon peak wavelength and also for the optical detection of various kinds of molecules. Moreover, this method may improve the measurement accuracy compared with existing approaches that use only one change (peak wavelength or peak intensity) as a readout value for the molecular detection.

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적외선 호밍 유도탄의 조준축 정렬에 관한 연구 (A Study on the Alignment of Aiming Sight Unit for Infrared Homing Missile)

  • 정영숙
    • 한국군사과학기술학회지
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    • 제7권3호
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    • pp.30-37
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    • 2004
  • For a proper operation of portable air defense IR terminal homing missile to the rapid intruding target, the boresight of an IR seeker of the missile should be accurately aligned with the gunner's aiming sight. Before a gunner fires the missile, he tries to keep the target within the circle of ASU ensuring the seeker to lock on the target correctly. In this paper, using an electrical seeker caging loop and IR detector signal characteristics, a precise aligning method between the seeker boresight and the LOS(Line of Sight) of ASU(Aiming Sight Unit) was studied. Although every seeker has slightly different SLA (Signal of Look Angle) output, we can get negligible alignment error through a fine tuning method of electrical caging signal. This alignment procedure was also adopted in K-PSAM system.