• 제목/요약/키워드: Hard Point

검색결과 609건 처리시간 0.023초

Effects of Suspension Compliance and Chassis Flexibility in Handling Performance (현가장치의 유연성과 차체의 탄성효과가 조종안정성에 미치는 영향 분석)

  • Kang, Dong-Kwon;Yoo, Wan-Suk
    • Journal of the Korean Society for Precision Engineering
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    • 제14권7호
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    • pp.137-143
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    • 1997
  • In this study, handling simulation of a passenger car is carried out to see the effects of suspension compliance, roll stabilizef bar and chassis flexibility. The front suspension of the car is a MacPherson strut type and the rear suspension is a multi-link type. The following five DADS models are constructed and compared to verify the effects of suspension compliance and chassis flexibility during lane change. (1) Vdhicle model without hard point compliance and stabilizer, (2) Vehicle model with hard point compoiance, (3) Vehicle model with hard point compliance and stabilizer, (4) Vehicle model with hard point compoiance, stabilizer, and one vibration mode of the chaxxis. (5) Vehicle model with hard point compliance, stabilizer, and three vibration modes of the chassis. The result shows that hard point compliance and stabilizer are significant in roll angle, and the flexibility of the chassis affects the yaw angle and yaw rate.

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Hard calibration of a structured light for the Euclidian reconstruction (3차원 복원을 위한 구조적 조명 보정방법)

  • 신동조;양성우;김재희
    • Proceedings of the IEEK Conference
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    • 대한전자공학회 2003년도 신호처리소사이어티 추계학술대회 논문집
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    • pp.183-186
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    • 2003
  • A vision sensor should be calibrated prior to infer a Euclidian shape reconstruction. A point to point calibration. also referred to as a hard calibration, estimates calibration parameters by means of a set of 3D to 2D point pairs. We proposed a new method for determining a set of 3D to 2D pairs for the structured light hard calibration. It is simply determined based on epipolar geometry between camera image plane and projector plane, and a projector calibrating grid pattern. The projector calibration is divided two stages; world 3D data acquisition Stage and corresponding 2D data acquisition stage. After 3D data points are derived using cross ratio, corresponding 2D point in the projector plane can be determined by the fundamental matrix and horizontal grid ID of a projector calibrating pattern. Euclidian reconstruction can be achieved by linear triangulation. and experimental results from simulation are presented.

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THE AMOUNT OF SOFT TISSUE CHANGE TO HARD TISSUE MOVEMENT FOLLOWING LE FORT II OSTEOTOMY (Le Fort II 골절단술을 이용한 비중안모 개선 효과에 대한 임상적 연구;경조직 이동에 따른 연조직 변화율에 대한 연구)

  • Kim, Myung-Jin;Yi, An-Na
    • Maxillofacial Plastic and Reconstructive Surgery
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    • 제22권1호
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    • pp.63-69
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    • 2000
  • Le fort II osteotomy is much useful technique to correct the midfacial hypoplasia including nasomaxillary complex especilly in patient with dish face appearance. Not in simple orthognathic surgery but in Le Fort II osteotomy, the standardization of prognostic value is essential in treatment planning to achieve satisfactory postoperative results. According to pervious reports, the ratio of soft tissue change to hard tissue movements varies as to different surgical methods and different facial regions. But there are few report about the ratio of soft tissue change to hard tissue movement following Le Fort II osteotomy. So we tried to develop standarized soft tissue surgical treatment objective. We have followed up 16 patients, who had received Le Fort II osteotomy by one operator from 1990 to 1996, one year postoperatively. In cephalometrics, we used Frankfort line as horizontal reference line, and vertical reference line as one drawn from Sella to horizontal line perpendicularly. The landmarks are G to soft tissue G, N on reference line to soft tissue N, ANS to Pn and A to Sn. The results are as follows. 1. The value of soft tissue change to hard tissue movement showed positive correlation, having statistical significancy at G, N2, N3 point. 2. At G, N2, N3 point, the ratio of soft tissue change to hard tissue movement was 0.51, 0.98 and 0.80 respectively and showed statistical significancy, while at N1, ANS, A point, that was 0.72, 0.49 and 0.26 but didn't showed statistical significance. 3. This result shows much the same change of the soft tissue change to hard tissue movement on the upper nasomaxilla, and less the same change on the lower maxilla and so the Le Fort II osteotomy can be recommended as a reliable effective operation method for correction of nasomaxillary retrusion.

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Genetic Algorithm Using-Floating Point Representation for Steiner Tree (스타이너 트리를 구하기 위한 부동소수점 표현을 이용한 유전자 알고리즘)

  • 김채주;성길영;우종호
    • Journal of the Korea Institute of Information and Communication Engineering
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    • 제8권5호
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    • pp.1089-1095
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    • 2004
  • The genetic algorithms have been used to take a near optimal solution because The generation of the optimal Steiner tree from a given network is NP-hard problem,. The chromosomes in genetic algorithm are represented with the floating point representation instead of the existing binary string for solving this problem. A spanning tree was obtained from a given network using Prim's algorithm. Then, the new Steiner point was computed using genetic algorithm with the chromosomes in the floating point representation, and it was added to the tree for approaching the result. After repeating these evolving steps, the near optimal Steiner tree was obtained. Using this method, the tree is quickly and exactly approached to the near optimal Steiner tree compared with the existing genetic algorithms using binary string.

Precision servo control of a computer hard disk (컴퓨터 하드 디스크의 정밀 서보 제어)

  • 전도영
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1996년도 한국자동제어학술회의논문집(국내학술편); 포항공과대학교, 포항; 24-26 Oct. 1996
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    • pp.286-289
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    • 1996
  • Two servo control algorithms are suggested to reduce the tracking error of a computer hard disk drive. One is the repetitive control to reduce the repeatable tracking error which is not explicitly taken into account in the design of a conventional controller. This algorithm was successfully applied to a commercial disk using a fixed point DSP. The other is the multi-rate sampling control which generates the control output between each sampling times since the sampling time of hard disk drives is limited. These algorithms were shown effectively to reduce tracking errors.

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Optimal Dimple Point of SFF HDD Suspension for Improving the Unloading Performance (언로드 성능 향상을 위한 딤플 포인트의 최적설계)

  • Kim, Ki-Hoon;Lee, Young-Hyun;Lee, Hyung-Jun;Park, No-Cheol;Park, Young-Pil
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 한국소음진동공학회 2007년도 춘계학술대회논문집
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    • pp.609-612
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    • 2007
  • The HDD (hard disk drive) using Load/Unload (L/UL) technology includes the benefits which are increased areal density, reduced power consumption and improved shock resistance than those of contact-start-stop (CSS). Dynamic L/UL has been widely used in portable hard disk drive and will become the key technology for developing the small form factor hard disk drive. The main design objectives of the L/UL mechanisms are no slider-disk contact or no media damage even with contact during L/UL, and a smooth and short unloading process. In this paper, we focus on lift-off force, pitch static attitude (PSA), roll static attitude (RSA) and dimple point. The "lift-off" force, defined as the minimum air bearing force, is another very important indicator of unloading performance. A large amplitude of lift-off force increases the ramp force, the unloading time, the slider oscillation and contact-possibility. PSA and RSA are also very important parameters in L/UL system and stability of slider is mainly determined by PSA and RSA. Dimple point by PSA and RSA is also important indicator. Therefore we find the optimal dimple point of SFF HDD suspension for improving the unloading performance.

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Studies on the Extractability and Characteristics of Actomyosin of Duck Muscle by Difference Scalding Method (침탕방법을 달리한 오리근육의 Actomyosin의 추출성과 특성에 관한 연구)

  • 정인철;이형걸;문윤희
    • Journal of the Korean Society of Food Science and Nutrition
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    • 제21권4호
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    • pp.348-352
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    • 1992
  • Investigation on the characteristics of actomyosin was prepared from leg and breast muscle of duck treated by hard scalding and subscalding method and their extractability , ATPase activity , solubility and SDS polyacrylamide gel electrophoresis were compared. The extractability of actomyosin in leg and breast muscle of duck by hard scalding was 7.84 and 39.84mg/g, whereas 4.79 and 28.04mg/g by subscalding respectively. Ca-ATPase activity of breast muscle wash higher than that of leg muscle. In case of leg muscle, hard scalding was higher tan subscalding. Breast muscle showed that subscalding was higher than hard scalding in less than ionic strength 0.08, and was lower than hard scalding in over ionic strength 0.08.Mg-ATPase was great in ionic strength and subcalding was relatively higher than hard scalding. Without regard to be treated method and part, the start point and end point of solubility were like. Hard scalded muscle and breast muscle showed that proteins in thin filament produced many extraction.

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Detection of Inflection Point of Waveform by Wavelet Threshold Denoising (웨이브릿 임계치 잡음제거에 의한 파형의 변곡점 검출)

  • Kim, Tae-Soo
    • Journal of the Korea Institute of Information and Communication Engineering
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    • 제13권10호
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    • pp.2205-2210
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    • 2009
  • In this paper, the proposed method is a denoising technology by tangent curve interpolation of zero points. The problem of the hard threshold method is improved by the proposed method. The quantity of time fluctuation of the electromagnetic signal as the quantity of electric fluctuation of the natural world or the curve of motion waveform of the fast movement of human extracted using virtual reality is, in fact, complex. Therefore it is important to decide exactly the signal properties as the inflection point for observation signal. In particular, it is necessary to extract the properties after denoising, since the measurement signal of the natural world include some noises. It shows that the noise of the inflection point signal with noise II, noise factor 5, is eliminated by the proposed method, and the result of SNR for the signal is improved 3.4dB than that by the conventional hard threshold.

Repetitive Control of Track Following Error in a Hard Disk Drive (하드 디스크 드라이브의 반복 추종 오차 제어)

  • Jeon, Doyoung;Jong, Ilyong
    • Journal of the Korean Society for Precision Engineering
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    • 제13권5호
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    • pp.131-138
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    • 1996
  • This paper suggests a servo control algorithm to reduce the repeatable tracking error which is not explicitly taken into account in the design of a conventional PID controller of a computer hard disk drive. The robust stability of the repetitive control system with multiplicative modelling error is analyzed, and the controller was implemented using a fixed point DSP(Digital Signal Processor). Experimental results show that the repetitive errors are suppressed effectively by the proposed controller.

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ASSESSMENT OF PORCINE FAT QUALITY BY FIBER-OPTIC SPECTROPHOTOMETRY

  • Irie, M.;Swatland, H.J.
    • Asian-Australasian Journal of Animal Sciences
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    • 제5권4호
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    • pp.753-756
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    • 1992
  • Research was undertaken to determine if relectance (interactance) measured with a portable fiver optic probe (Colormet) can be used to assess porcine fat quality. Soft fat generally had lower interactance than hard fat, p<0.05 from 400 to 700 nm, although interactance spectra of hard and soft fat were similar in shape. At $4^{\circ}C$, interactance from 450 nm to 700 nm at the inner layer of backfat was correlated (p<0.01) with subjective soft fat score (r = 0.06 to 0.70), and with the refractive index (r = -0.62 to -0.65) and melting point (r = 0.59 to 0.60) of heat-extracted lipid. Colormet interactance $L^*$ at $4^{\circ}C$ was correlated (p<0.01) with soft fat score (r = 0.72), refractive index (r = -0.66) and melting point (r = 0.61). Interactance decreased as the temperature of the fat was increased from 22 to $44^{\circ}C$ (p<0.01). Soft fat had lower interactance than fats that were slightly soft, slightly hard and hard at 4, 22 and $40^{\circ}C$, although softness and temperature may interact to affect interactance. These results indicate that soft porcine fat may be detected easily by fiber-optic spectrophotometry.