• 제목/요약/키워드: Hard Disk

검색결과 622건 처리시간 0.027초

On Application of Optimization Scheme To Direct Numerical Analysis Of Slider

  • Hwang, Pyung;Khan, Polina;Pan, Galina
    • KSTLE International Journal
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    • 제5권1호
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    • pp.23-27
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    • 2004
  • The object of the present work is the numerical analysis of the computer hard disk slider. The pressure between slider and disk surfaces is calculated using the Boundary Fitted Coordinate System and Divergence Formulation for the nonlinear Reynolds' equation solution. The optimization scheme is applied to search for the steady state position of the slider. The simplified method is given for the case of the fixed inclined pad. The film thickness ratios and pitching and rolling angles are considered as alternative choice of the slider's coordinates. The behavior of the objective function for the Negative Pressure slider is studied in details. Methods of conjugate directions and feasible directions are applied.

HDD 회전형구동장치의 피봇비선형성 측정 및 모델링 (Pivot Nonlinearity in Disk Drive Rotary Actuator : Measurement and Modeling)

  • 박재흥;변용규;장흥성;노광춘
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 1996년도 추계학술대회 논문집
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    • pp.419-424
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    • 1996
  • As track density increases, the effects of nonlinearity in pivot bearing of hard disk drive on the servo performance are becoming more important in considering the range of inertia force and the input torque during settling and tracking mode. Recently, an increasing attention is given to more precise experimental observations and modelings of pivot nonlinearity for achieving higher performance of servo control. In this paper, we propose a new model that shows an improved prediction of the pivot nonlinearity than existing preload-plus-two-slope model at matching simulations and experimental results in both time and frequency domains. Experimental measurements are carried out to validate and identify the specific nonlinearity presents in the pivot bearing when its in fine motion. Using the experimental results new model along with the existing one are characterized and compared for relevancies.

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하드디스크 드라이브에서의 소음 저감에 관한 연구 (A Study of Noise Reduction in Hard Disk Drive)

  • 곽주영;손진승;이행수;홍민표;고정석;조은형;좌성훈
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2001년도 추계학술대회논문집 II
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    • pp.579-585
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    • 2001
  • This paper proposed a method of reducing a noise in hard disk drive. This method is performed through three parts of procedures. First procedure is sound-oriented experiment, which contains sound intensity techniques and measurements of sound pressure level and sound power. Second is vibration-oriented experiment, which contains FRF(Frequency Response Function) analysis and disk vibration reduction techniques. And the third is computer-oriented simulation, which contains modal analysis and force vibration analysis using ANSYS and sound radiation prediction using SYSNOISE. As these three parts can affect with each other, they should be considered and conducted simultaneously. Through this procedure sound power is measured 2.7 Bels in idle-spinning mode, which is the lowest noise level in the HDD industries.

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학원 교육 콘텐츠 S/W 저작권 보호를 위한 알고리즘 구현 (Implementation of Security Algorithm to Preserve Copyright of Education Contents)

  • 강민재;편도길;정상호;정회경
    • 한국정보통신학회:학술대회논문집
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    • 한국해양정보통신학회 2011년도 춘계학술대회
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    • pp.324-326
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    • 2011
  • 최근 교육 콘텐츠 개발이 활발한 가운데, 콘텐츠를 소비하는 소프트웨어(Software)의 저작권을 보호할 수 있는 방법이 다양하게 연구되고 있다. 따라서 본 연구는 이더넷(Ethernet)의 맥 주소(MAC Address)와 하드디스크 볼륨 시리얼 넘버(Hard Disk Volume Serial Number)를 통해서 소프트웨어의 저작권을 보호하기 위한 방안을 고찰, 구현 하였다. 본 연구를 통해 간단하지만 강력한 저작권 보호를 위한 알고리즘을 구현하여, 학원 교육 콘텐츠 소 프트웨어의 저작권 보호를 강화하고, 불법적 소프트웨어 사용으로 인한 피해를 감소하는데 기여할 것이다.

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하드디스크 드라이브 액추에이터 시스템의 수학적 모델 (Mathematical Model of Hard Disk Drive Actuator System)

  • 권순억;박노열;김준오;정태건
    • 대한기계학회논문집A
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    • 제24권12호
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    • pp.3080-3087
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    • 2000
  • We obtain the mathematical model of the hard disk drive actuator system the system response data of the finite element analysis or experimental results. The model is base on the Rayleigh-Ritz method to approximate the dynamic response of the actuator system. The basic idea is to use the curve-fit technique to obtain the approximation coefficients. It allows the dynamic analysis of the actuator system without resort to the repetitive finite element modeling work. Even though the dynamic characteristics of the system of the system are affected somewhat by the structural modification and the change of the material properties, we can use the modified size and dynamic properties of the actuator system in the mathematical model to some extent. In this study, we express the mathematical model of the simplified rectangular plate first and then proceed to the actual hard disk drive actuator system.

헤드/디스크 인터페이스 내에서 오염 입자의 거동에 관한 수치적 연구 (Numerical Investigation of Contamination Particle's Trajectory in a Head/slider Disk Interface)

  • 박희성;황정호;좌성훈
    • 대한기계학회논문집B
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    • 제24권3호
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    • pp.477-484
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    • 2000
  • Microcontamination caused by particle deposition on the head disk interface threatens the reliability of hard disk drive. Design of slider rail to control contamination becomes an important issue in magnetic recording. In this paper, how particles adhere to the slider and the disk is examined. To investigate accumulation mechanism of the particles, trajectory of the particles in a slider/disk interface is simulated with considering various forces including drag force, gravitational force, Saffman lift force, and electrostatic force. It is found that the charged particles can easily adhere to the slider or disk surface, if an electric field exists between the slider and the disk. It is supposed that the vertical motion of the particles should be related with not only Saffman force but also electrostatic force.

고밀도 디스크 드라이브를 위한 디스크 두께와 Pemto 슬라이더가 PES에 미치는 영향 (Effects of Disk Thickness and Pemto Slider on Position Error Signal for High TPI Hard Disk Drive)

  • 한윤식;이호성;송용한
    • 정보저장시스템학회논문집
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    • 제1권1호
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    • pp.23-28
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    • 2005
  • This paper investigates the effects of disk thickness and Pemto slider on PES(position error signal) for high TPI(track per inch) drives above 150kTPI at early stage of their development. In order to reduce the disk flutter which becomes a dominant contributor to the TMR, the thicker disks with both 63 and 69mi1 have been used. Also, PES of a Pemto slider with thinner thickness than Pico slider has been estimated to decrease the conversion factor of disk motion in axial direction to head off-track motion. A frequency-domain PES estimation and prediction tool has been developed via measurement of disk flutter and HSA(head stack assembly) forced vibration. It has been validated by the measured PES in drive level. Based on the model and measurement of disk flutter, PES of a drive with the thicker disk and Pemto slider is predicted and their impact is investigated.

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1Tb/in$^2$의 정보저장을 위한 MEMS/NEMS 기술

  • 이동원
    • 세라미스트
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    • 제7권3호
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    • pp.15-20
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    • 2004
  • 일반적으로 정보 저장장치라고 하면 컴퓨터의 하드디스크나 음악을 듣기 위해 이용되는 컴팩트디스크(compact disk- read only memory, CD-ROM)를 생각하게 된다. 1956년 미국 캘리포니아주의 산호세에 위치한 IBM의 한 연구소에서 자성체를 이용한 정보저장장치(hard disk, HD) RAMAC 이 처음 개발된 이래 지난 50년간 HD는 매년 60~100%의 저장용량의 능력을 증가시키며 컴퓨터 산업과 더불어 눈부시게 성장해 오고 있다. (중략)

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