• 제목/요약/키워드: spin mode

검색결과 77건 처리시간 0.026초

훈련기 스핀모드 향상을 위한 수직 풍동시험 (The Vertical Wind Tunnel Test for Spin Mode Improvement of KTX-1)

  • 고준수;정인재
    • 제어로봇시스템학회논문지
    • /
    • 제11권3호
    • /
    • pp.228-232
    • /
    • 2005
  • This paper presents the efforts of the studies for improvement of spin characteristics of KTX-1 #02 through rotary balance test, forced oscillation test and spin mode analysis. During the full scale development design stage, we had fullfilled a lot of spin flight test, spin mode analysis. Based on all of the efforts, KTX-1 had been developed as a successful trainer with excellent spin characteristics.

화합물 반도체 본딩용 Spin Coater Module의 동특성 평가 (Dynamic Characteristic Evaluation of Spin Coater Module for GaAs Wafer Bonding)

  • 송준엽;김옥구;강재훈
    • 한국정밀공학회지
    • /
    • 제22권6호
    • /
    • pp.144-151
    • /
    • 2005
  • Spin coater is regarded as a major module rotating at high speed to be used build up polymer resin thin film layer fur bonding process of GaAs wafer. This module is consisted of spin unit for spreading uniformly, align device, resin spreading nozzle and et. al. Specially, spin unit which is a component of module can cause to vibrate and finally affect to the uniformity of polymer resin film layer. For the stability prediction of rotation velocity and uniformity of polymer resin film layer, it is very important to understand the dynamic characteristics of assembled spin coater module and the dynamic response mode resulted from rotation behavior of spin chuck. In this paper, stress concentration mode and the deformed shape of spin chuck generated due to angular acceleration process are presented using analytical method for evaluation of structural safety according to the revolution speed variation of spin unit. And also, deformation form of GaAs wafer due to dynamic behavior of spin chuck is presented fur the comparison of former simulated results.

Two Dimensional Transfer Modes in $CH_2$ Spin System

  • NamGoong Hyun
    • 한국자기공명학회논문지
    • /
    • 제10권1호
    • /
    • pp.59-73
    • /
    • 2006
  • Spin-lattice relaxation pathway of $CH_2$ spin system by two dimensional NOESY sequence has been discussed. Two-dimensional spectra governed by dipolar relaxation mechanism were simulated in term of transfer mode, the generalization of conventionally used magnetization mode in one dimension. The transfer matrix directly related to the Redfield relaxation matrix can be constructed by the multiplet of transfer mode. The observable relaxation transfer modes causes to variation of the off-diagonal signal intensity of phase sensitive NOESY spectra from which variable spectral density can be extracted with simple group theoretical calculation. The variation of the J-coupling peak intensity as a function of the mixing time in 2-D spectra for $n-Undecane-5-^{13}C$ and Bromoacetic $2-^{13}C$ acid has been theoretically traced.

  • PDF

IPTV 셋톱박스 환경에서 스트리밍 데이터 재생을 위한 전력 소모 감소 기법 (Low Power Consumption Technology for Streaming Data Playback in the IPTV Set-top Box)

  • 고영욱;양준식;김덕환
    • 전자공학회논문지CI
    • /
    • 제47권1호
    • /
    • pp.30-40
    • /
    • 2010
  • IPTV 셋톱박스에서 가장 많이 사용하는 저장장치인 하드디스크는 가격에 비해 저장용량이 크고 입출력 속도가 빠르지만 스핀들 모터의 기계적 동작으로 인해 전력 소모가 많다는 단점이 있다. 셋톱박스에서 스트리밍 데이터를 재생하기 위하여 하드디스크의 스핀들 모터는 최대 전력을 사용하는 활성모드를 계속 유지해야 한다. 본 논문에서는 스트리밍 데이터 재생 시 전력 소모를 감소시키는 오프셋-버퍼링(Offset-Buffering)과 다중모드 스핀-다운(Multi Mode Spin-Down) 기법을 제안한다. 오프셋-버퍼링은 사용자의 시청 패턴을 분석하고 분석된 결과를 통해 버퍼링을 하므로 스핀들 모터의 모드를 대기모드로 길게 유지할 수 있다. 또한 오프셋 버퍼의 크기에 따라 다양한 모드로 스핀-다운을 하여 전력 소모를 줄일 수 있다. 실험 결과 본 논문에서 제안한 오프셋-버퍼링과 다중모드 스핀-다운은 기존의 풀-버퍼링(Full-Buffering)보다 28.3% 전력 소모량을 감소시켰으며, 스핀-업 횟수를 12.5% 줄였다.

비선형 슬라이드 모드 제어를 적용한 원심력을 갖는 도립진자 제어기의 구현 (A Implementation of an Inverted Pendulum with Centrifugal Force using the NonLinear Sliding Mode Contrl)

  • 황윤호;원태현;이만형
    • 한국정밀공학회:학술대회논문집
    • /
    • 한국정밀공학회 1995년도 추계학술대회 논문집
    • /
    • pp.606-609
    • /
    • 1995
  • To stabilize a satellite, a spin stabilization method is used for attitude control. The spin stabilization uses the centrifugal force of a pendulum damper which is tilted long boom, to stabilize the unstable satellite. In this paper, an inverted pendulum system is implemented which is similar to the spin stabilization method. Study on the velocity of the rotation axis and the inverted pendulum's angle stability is shown. We designed a controller using a 32bit TMS320C31 DSP for the CPU and also performances by PLD control and Sliding Mode Control is compared.

  • PDF

Continuous Propionic Acid Production from Cheese Whey Using In Situ Spin Filter

  • Gupta, Achin;Srivastava, Ashok K.
    • Biotechnology and Bioprocess Engineering:BBE
    • /
    • 제6권1호
    • /
    • pp.1-5
    • /
    • 2001
  • The potential use of spin filter device to retain Propionibacterium acidipropionici in the bioreactor under continuous mode of fermentation, and improve acid productivity, was examined. The yield of propionic acid based on lactose concentration was 51% in batch and 54% in continuous (dilution rate = 0.05 h(sup)-1) operation. The yield in continuous fermentation with cell retention using spin filter of 10 micron size (dilution rate = 0.05 h(sup)-1) was even higher at 70% (w/w). The volumetric productivity under batch and continuous mode of operation were 0.312g L(sup)-1 h(sup)-1 and 0.718g L(sup)-1 h(sup)-1 respectively. Continuous fermentation with cell retention demonstrated even higher volumetric productivities at 0.98g L(sup)-1 h(sup)-1 with out clogging problems. It could be used for utilization of cheese whey to produce propionic acid at higher yield and productivities.

  • PDF

Experimental Evidence for New Pinning Conditions in Strongly Pinned Permalloy Film

  • Han, Kyung-Hunn;Cho, Jae-Hun;Lee, Suk-Mock
    • Journal of Magnetics
    • /
    • 제12권1호
    • /
    • pp.27-30
    • /
    • 2007
  • Experimental evidence suggests that spin pinning conditions for standing spin mode in polycrystalline $Ni_{84}Fe_{16}$ alloy film, is confirmed using the four categories of Camley et al. and the value of q$\bot$ for the pinning conditions, this was achieved by performing Brillouin light scattering measurements. The value of q$\bot$ was observed, in order to increase at a rate of $\pi$/2 with an increasing mode number. With this condition, the coexistence of standing spin wave modes was shown, with intermediate pinning, in addition to free and strong pinning. The values for spin-wave-stiffness constant ($D_B$), g-factor (g), and surface magnetization (4$\pi$M) of the Permalloy film were obtained from the results of BLS, and determined to be $D_B=1.85{\pm}0.05Oecm^2$, $g=2.11{\pm}0.02$, and 4$\pi$M=8.7 kG, respectively.