• Title/Summary/Keyword: Motion reduction

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A Study on the Control of Ship Motion using the Anchor Dredging (닻을 운용한 선체운동 제어)

  • 윤순동
    • Proceedings of KOSOMES biannual meeting
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    • 2002.10a
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    • pp.127-134
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    • 2002
  • Ship operators are used to dredge anchor for the collision avoidance or safety of ship handling in a harbour or narrow channel. This paper clarifies the technique using tile anchor dredging known as a common sense for the seafarers. A mathematical model at low speed range has been established for the estimation of ship motion under the assumed environment , simulate the advance speed , and turning ability under the anchor dredging or not. The results shows good agreement with the conventional seamanship and their experiences as follows. Ahead speed used the anchor dredging is slower(speed reduction ratio:40%) than the normal ahead speed and the stopping distance is shorter (distance reduction ratio:40%)than the normal ahead distance without the anchor dredging. Turning speed used anchor dredging is slower(speed reduction ratio:72%)than the normal ahead speed and the tactical diameter is shorter(distance reduction ratio:24%)than the diameter by the normal turning without the anchor dredging.

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Simulation of Particle Beds with Combustion and Reduction in Steel Making Rotary Kilns (제철용 로터리 킬른 내의 연소 및 환원을 포함한 입자 거동 예측모사 해석)

  • Han, Woojoo;Jang, Kwonwoo;Han, Karam;Huh, Kang Y.
    • 한국연소학회:학술대회논문집
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    • 2015.12a
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    • pp.173-175
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    • 2015
  • We simulate the particle bed motions with combustion and reduction in steel making rotary kilns. The particle bed motions are simulated by a Lagrangian approach called Discrete Phase Model (DPM). To reduce the number of tracking particles, the Coarse Grain Model (CGM) was applied. The model for particle motions showed good agreements with experimental results. In addition to the particle motion, the combustion and reduction simulation was performed. The combustion and reduction simulation can consider heat, mass and momentum transfer between the gas phase and particle beds.

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Drag Reduction in Turbulent Channel flow with Periodically Arrayed Heating and Cooling Strips (난류 채널 내 냉·열판 부착에 의한 마찰저항 감소)

  • Yoon, Hyun-Sik;Chun, Ho-Hwan
    • Journal of the Society of Naval Architects of Korea
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    • v.42 no.6 s.144
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    • pp.608-618
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    • 2005
  • A new technique giving significant drag reduction in turbulent shear flows has been proposed by using the buoyancy effect to generate periodic spanwise motion. Such spanwise motion can be obtained by arranging heating and cooling strips periodically aligned in the spanwise direction of a vertical channel, where the streamwise mean flow is perpendicular to the gravity vector The strip size has been changed in order to obtain the optimum size corresponding to the maximum drag reduction. The bulk Reynolds number, $ Re_{m} = U_{m} \delta / \nu \$ is fixed at 2270 while Grashof numbers is changed between $10^{6}$ to $10^{7}$. As Grashof number increases, considerable drag reduction can be obtained, At the highest Grashof number, an optimum strip size of about 250 wail units gives drag reduction of about 35$\%$. The greater the Grashof number, the smaller the strip size attains the maximum drag reduction.

Sub-pixel Motion Estimation Algorithm with Low Computation Complexity for H.264 Video Compression (H.264 동영상 압축을 위한 낮은 복잡도를 갖는 부 화소 단위에서의 움직임 추정)

  • Lee, Yun-Hwa;Shin, Hyun-Chul
    • Proceedings of the IEEK Conference
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    • 2005.11a
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    • pp.639-642
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    • 2005
  • Motion Estimation(ME) is an important part of video compression, because it requires a large amount of computation. Half-pixel and quarter-pixel motion estimation allows high video compression rates but it also has high computation complexity. In this paper we suggest a new and efficient motion estimation algorithm for half-pixel and quarter-pixel motion estimation using SAD values. In the method, an integer-pixel motion vector is found and then only three neighboring points of the integer-pixel motion vector is evaluated to find the half-pixel motion vector. The quarter-pixel motion vector is also found by using a similar method. Experimental results of our method shows 20% reduction in computation time, when compared with those of a conventional method, while producing same quality motion vectors.

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An Efficient Global Motion Estimation based on Robust Estimator

  • Joo, Jae-Hwan;Choe, Yoon-Sik
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • 2009.01a
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    • pp.408-412
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    • 2009
  • In this paper, a new efficient algorithm for global motion estimation is proposed. This algorithm uses a previous 4-parameter model based global motion estimation algorithm and M-estimator for improving the accuracy and robustness of the estimate. The first algorithm uses the block based motion vector fields and which generates a coarse global motion parameters. And second algorithm is M-estimator technique for getting precise global motion parameters. This technique does not increase the computational complexity significantly, while providing good results in terms of estimation accuracy. In this work, an initial estimation for the global motion parameters is obtained using simple 4-parameter global motion estimation approach. The parameters are then refined using M-estimator technique. This combined algorithm shows significant reduction in mean compensation error and shows performance improvement over simple 4-parameter global motion estimation approach.

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Motion Blur Reduction in LCDs

  • Hong, Sun-Kwang;Oh, Jae-Ho;Park, Po-Yun;Park, Jin-Hyeok
    • 한국정보디스플레이학회:학술대회논문집
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    • 2004.08a
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    • pp.1108-1110
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    • 2004
  • LCDs show motion image blur due to slow response time and a hold-type driving method. In this paper, we investigate motion blur phenomena and quantitatively show that the motion blur can be significantly reduced through a combination of dynamic capacitance compensation (DCC) and black data insertion.

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Motion Blur reduction based on Motion Compensation

  • Park, Jae-Hyeung;Kim, Yun-Jae;Park, Min-Kyu;Amino, Tadashi;Oh, Jae-Ho;Kim, Nam-Deog;Kim, Sang-Soo
    • 한국정보디스플레이학회:학술대회논문집
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    • 2007.08a
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    • pp.413-416
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    • 2007
  • Motion-estimation/motion-compensation (ME/MC) provides superior motion picture quality but its huge computation load results in high cost. Impulsive driving is a cost-effective solution but it suffers from large flicker and brightness loss. Motion compensated impulsive driving technology has been developed to achieve high motion picture quality in a cost-effective implementation by combining ME/MC and impulsive driving. The key idea is to apply ME/MC or impulsive driving selectively according to the motion vector distribution of the incoming image sequence. In this paper, the description of the algorithm and the experimental results are provided.

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Effect of Complex Korean Medical Treatment in Patients with Frozen Shoulder: A Retrospective Chart Review (동결견 환자에 대한 한의복합치료 효과: 후향적 차트 리뷰)

  • SeongHwan Ko;Eun-Jung Lee
    • Journal of Korean Medicine Rehabilitation
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    • v.33 no.3
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    • pp.115-127
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    • 2023
  • Objectives Through this study, we investigated the effects of Korean medicine treatments on range of motion recovery and pain reduction in patients with Frozen shoulder. Methods In this study, the medical records of 26 patients diagnosed with frozen shoulder were retrospectively observed and analyzed through the IBM SPSS Statistics 25 program. We used range of motion to observe the patient's motion recovery and numeric rating scale to evaluate pain reduction. Results The shoulder range of motion increased statistically significantly from 160.0 (123.5~170.0) to 170.0 (160.0~180.0) (flexion), 115.0 (90.0~135.0) to 167.5 (130.0~178.8) (abduction), 40.8±22.1 to 58.3±16.0 (external rotation) (p<0.001). The average of numeric rating scale reduced statistically significantly from 6.7±2.0 to 3.2±1.4 (p<0.001). Depending on the period, the range of motion increased statistically significantly when visited within 3 months, also the pain score decreased 7.0 (5.4~8.0) to 3.0 (1.8~3.6) statistically significantly when visited within 3 months. In the treatment intervention, the increase in the range of motion and the decrease in pain were statistically significant, especially when the bee venom acupuncture and chuna manaul therapy were used together. Conclusions Korean medicine treatments was effective in improving the range of motion and reducing pain in frozen shoulders. In particular, when treated within 3 months of onset and when bee venom acupuncture and chuna manual therapy were used together, it was effective in recovering the range of motion and reducing pain.

Experimental Study on the Reduction of Vertical Motion of Floating Body Using Floating-Submerged Bodies Interaction (부유체-몰수체 상호작용을 이용한 부유체 상하운동 저감에 대한 실험적 연구)

  • Shin, Min-Jae;Koo, WeonCheol;Kim, Sung-Jae;Heo, Sanghwan;Min, Eun-Hong
    • Journal of the Society of Naval Architects of Korea
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    • v.54 no.6
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    • pp.485-491
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    • 2017
  • An experimental study on the reduction of vertical motion of floating body using floating-submerged body interaction was performed in a two-dimensional wave channel. The system consisting of a floating and submerged body that only move vertically was modeled. This experiment was designed based on the results of theoretical analysis of two-body interaction. The results showed a tendency to significant reduction of heave RAO of floating body due to submerged body. Various connection line stiffness and dimension of the submerged body were applied to investigate the effect of two-body interaction on the vertical motion of the bodies, Heave RAOs of the floating-submerged body were compared with those of single body. From the comparison study, we obtained an optimum condition of connection line and dimension of submerged body for maximum heave reduction at the resonant period of single body.

Motion Adaptive Temporal Noise Reduction Filtering Based on Iterative Least-Square Training (반복적 최적 자승 학습에 기반을 둔 움직임 적응적 시간영역 잡음 제거 필터링)

  • Kim, Sung-Deuk;Lim, Kyoung-Won
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.47 no.5
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    • pp.127-135
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    • 2010
  • In motion adaptive temporal noise reduction filtering used for reducing video noises, the strength of motion adaptive temporal filtering should be carefully controlled according to temporal movement. This paper presents a motion adaptive temporal filtering scheme based on least-square training. Each pixel is classified to a specific class code according to temporal movement, and then, an iterative least-square training method is applied for each class code to find optimal filtering coefficients. The iterative least-square training is an off-line procedure, and the trained filter coefficients are stored in a lookup table (LUT). In actual noise reduction filtering operation, after each pixel is classified by temporal movement, simple filtering operation is applied with the filter coefficients stored in the LUT according to the class code. Experiment results show that the proposed method efficiently reduces video noises without introducing blurring.