• Title/Summary/Keyword: diagonal method

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Effects of Diagonal Pattern Self-Exercise on Trunk Control, Balance, and Gait Ability in Chronic Stroke Patients

  • Yang, Jaeho;Park, Shinjun;Kim, Soonhee
    • Journal of International Academy of Physical Therapy Research
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    • v.11 no.2
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    • pp.2028-2035
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    • 2020
  • Background: Weakness of the trunk muscles decreases the trunk control ability of stroke patients, which is significantly related to balance and gait. Objectives: To compare the impact of diagonal pattern self-exercise on an unstable surface and a stable surface for trunk rehabilitation on trunk control, balance, and gait ability in stroke patients. Design: Nonequivalent control group design. Methods: Twenty four participants were randomized into the experimental group (diagonal pattern self-exercise while sitting on an unstable surface, n=12) and the control group (diagonal pattern self-exercise while sitting on a stable surface, n=12). All interventions were conducted for 30 minutes, three times a week for four weeks, and the trunk impairment scale (TIS), berg balance scale (BBS), functional gait assessment (FGA), and G-walk were measured. Results: All groups indicated significant increases in all variables (TIS, BBS, FGA, cadence, speed, stride length) after four weeks. The TIS, BBS, FGA, cadence, gait speed, and stride length group-by-time were significantly different between the two groups. Conclusion: We found that, in stroke patients, diagonal pattern self-exercise on an unstable surface is a more effective method for improving trunk control, balance, and gait ability than diagonal pattern self-exercise on a stable surface.

A Method for Mapping Semi-Diagonal of Intra Prediction to Edge Information of MPEG-7 EHD (인트라 예측의 Semi-Diagonal을 EHD 에지 정보로 맵핑하는 방법)

  • Kwon, Yong-Kwang
    • Proceedings of the Korean Society of Computer Information Conference
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    • 2012.07a
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    • pp.87-88
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    • 2012
  • Because intra prediction modes in H.264 are determined by the brightness continuity between neighboring blocks, they can be used as a method for extracting edge information in the compression domain. However, if we just consider 9 intra prediction modes in H.264 as 9 different edge directions, we have the following two problems. First, intra prediction modes tend to yield too many edge blocks, generating unnecessary edge information. Second, we may not need all 9 directional edges (including the DC type) in H.264 intra prediction modes. For example, the EHD (edge histogram descriptor) in MPEG-7 defines only 4 directional edge types, namely horizontal, vertical, diagonal (HVD) edges with $0^{\circ}$, $90^{\circ}$, $45^{\circ}$, and $135^{\circ}$. Here, semi-diagonal (SD) edge types with $112.5^{\circ}$, $157.5^{\circ}$, $22.5^{\circ}$, and $67.5^{\circ}$ in the intra prediction modes in H.264 are not used. In this paper. we prepose a method that removes unnecessary edges from the intra prediction modes by utilizing the total average coefficient of 4x4 blocks in each slice and assign SD edges to HVD (horizontal, vertical, diagonal, $0^{\circ}$, $90^{\circ}$, $45^{\circ}$, $135^{\circ}$) edges by the contextual information of the neighboring blocks. Experimental results show that the edges determined by the proposed method in the compression domain are comparable to those of the previous edge detection methods in the spatial domain.

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FAST MATRIX SPLITTING ITERATION METHOD FOR THE LINEAR SYSTEM FROM SPATIAL FRACTIONAL DIFFUSION EQUATIONS

  • LIANG, YUPENG;SHAO, XINHUI
    • Journal of applied mathematics & informatics
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    • v.38 no.5_6
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    • pp.489-506
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    • 2020
  • The spatial fractional diffusion equation can be discretized by employing the implicit finite difference scheme using the shifted Grünwald formula. The discretized linear system is obtained, whose the coefficient matrix has a diagonal-plus-Toeplitz structure. In order to solve the diagonal-plus-Toeplitz linear system, on the basis of circulant and skew-circulant splitting (CSCS splitting), we construct a new and efficient iterative method, called DSCS iterative methods, which have two parameters. Than we prove the convergence of DSCS methods. As a focus, we derive the simple and effective values of two optimal parameters under some restrictions. Some numerical experiments are carried out to illustrate the validity and accuracy of the new methods.

An Analysis of Internal Flow of Diagonal Flow Blower with Quasi-Three-Dimensional Calculation Method Considering the Spanwise Mixing due to Secondary Flow (이차흐름에 의한 스팬방향의 믹싱효과를 고려한 준3차원 계산법을 이용한 사류송풍기 내부흐름의 해석)

  • Park, S.R.;Kim, Y.J.;Kim, T.W.
    • Solar Energy
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    • v.19 no.4
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    • pp.21-31
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    • 1999
  • This paper presents a quasi-three-dimensional calculation method considered a spanwise mixing effect in a diagonal flow impeller. The effect of this spanwise mixing caused by spanwise distribution of blade loading is evaluated by a secondary flow theory. In order to verify the validity of this method, it is applied to the analysis of a diagonal flow fan designed under a vortex type of constant circumferential velocity and that of a free vortex. The comparison of the calculated result with experimental data shows a good agreement except the regions near the casing where the flow field is affected by the tip leakage flow.

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A Study on the Effectiveness of Averaged MUSIC Using Limited Number of Sensors (제한된 수의 Sensor를 이용한 Averaged MUSIC의 효율성에 관한 연구)

  • 김영집
    • Proceedings of the Acoustical Society of Korea Conference
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    • 1993.06a
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    • pp.206-209
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    • 1993
  • The main purpose of this paper is to verify the effectiveness of a high resolution direction finding method, so called the‘averaged MUSIC’. This method uses a new sample array covariance matrix that consists of diagonal components obtained by taking averages of the diagonal component values of the sample covariance matrix for the MUSIC. The paper shows that the proposed method performs higher resolved direction-of-arrival estimation and better resolution probability than the MUSIC in such cases as low signal-to-noise ratio, when the number of sensors used is finite, based on the statistical analysis.

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MULTI SPLITTING PRECONDITIONERS FOR A SYMMETRIC POSITIVE DEFINITE MATRIX

  • Yun Jae-Heon;Kim Eun-Heui;Oh Se-Young
    • Journal of applied mathematics & informatics
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    • v.22 no.1_2
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    • pp.169-180
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    • 2006
  • We study convergence of multisplitting method associated with a block diagonal conformable multisplitting for solving a linear system whose coefficient matrix is a symmetric positive definite matrix which is not an H-matrix. Next, we study the validity of m-step multisplitting polynomial preconditioners which will be used in the preconditioned conjugate gradient method.

Internal Flow Analyses of Diagonal Type Blowers Using a Quasi-3-Dimensional Method Considering Spanwise Mixing and Tip Clearance Effect Due to Secondary Flows (이차흐름에 의한 스팬방향의 믹싱효과와 선단틈새흐름을 고려한 준 삼차원 사류송풍기 내부흐름 해석)

  • Kim, Chan-Kyu;Jun, Yong-Du;Kim, Tae-Whan
    • 유체기계공업학회:학술대회논문집
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    • 2002.12a
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    • pp.137-146
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    • 2002
  • This paper presents a quasi-3-dimensional calculation method considering secondary flows in the impellers of diagonal flow blowers. A Quantitative estimation of the secondary flow effects is made by using secondary flow theories. In order to verify the validity of the adopted models, that is, span-wise mixing model and the tip clearance model, numerical simulations are performed for two different types of impellers of diagonal flow blowers which are designed differently. Numerical experiments are conducted for each of a constant tangential velocity type impeller, and a free vortex type impeller, both at two different flow coefficients. According to the simulation results, it was found that the present model considering span-wise mixing and tip clearance effect shows better agreements with the experimental data than those without these models in terms of the flow velocity and the angle distribution.

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Precoding Method for Increasing System Capacity in Multiuser MIMO Downlink Channels (다중사용자 MIMO 하향링크 채널 환경에서 시스템 용량 향상을 위한 프리코딩 기법)

  • Kim, Kwang-Yoon;Lee, Jong-Sik;Koo, Sung-Wan;Yang, Jea-Su;Kim, Jin-Young
    • 한국정보통신설비학회:학술대회논문집
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    • 2008.08a
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    • pp.12-16
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    • 2008
  • In this paper, we study precoding techniques for co-channel interference suppression in multiuser MIMO systems. DPC is optimal techniques to achieve the system capacity of multiuser MIMO downlink channels. DPC is not proper in practical wireless systems because complexity is very high. So block diagonal precoding for multiuser MIMO downlink channel is studied. The block diagonal precoding is used to suppress co-channel interference between multiuser. Block diagonal precoding method, whose complexity is reduced by modified null space operation, change multiuser MIMO channel to multiple single-user MIMO channel. We also use V-BLAST decoder in receiver. V-BLAST decoder can achieve increased system capacity in proportion to the number of users. We show improved system performance by using computer simulation.

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Robust compensator design for parametric uncertain systems by separated optimizations (분리최적화 기법을 이용한 강인제어기 설계)

  • 김경수;박영진
    • 제어로봇시스템학회:학술대회논문집
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    • 1996.10b
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    • pp.589-592
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    • 1996
  • It is well known that robust compensators designed by the block-diagonal Lyapunov function approaches are conservative while they are popular in practice because of their computational easiness. In this note, we develop a systematized version of conventional block-diagonal Lyapunov function approaches by deriving two separated optimizations based on the guaranteed cost control method. The proposed method generates reasonable robust compensators in practice.

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Image Segmentation Using Anisotropic Diffusion Based on Diagonal Pixels (대각선 방향 픽셀에 기반한 이방성 확산을 이용한 영상 분할)

  • Kim Hye-Suk;Yoon Hyo-Sun;Toan Nguyen Dinh;Yoo Jae-Myung;Lee Guee-Sang
    • The Journal of the Korea Contents Association
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    • v.7 no.2
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    • pp.21-29
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    • 2007
  • Anisotropic diffusion is one of the widely used techniques in the field of image segmentation. In the conventional anisotropic diffusion [1]-[6], usually 4-neighborhood directions are used: north, south, west and east, except the image diagonal directions, which results in the loss of image details and causes false contours. Existing methods for image segmentation using conventional anisotroplc diffusion can't preserve contour information, or noises with high gradients become more salient as the umber of times of the diffusion increases, resulting in over-segmentation when applied to watershed. In this paper, to overcome the shortcoming of the conventional anisotropic diffusion method, a new arusotropic diffusion method based on diagonal edges is proposed. And a method of watershed segmentation is applied to the proposed method. Experimental results show that the process time of the proposed method including diagonal edges over conventional methods can be up to 2 times faster and the Circle image quality improvement can be better up to $0.45{\sim}2.33(dB)$. Experiments also show that images are segmented very effectively without over segmentation.