• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.6
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• pp.150-157
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• 2019

The purpose of this study was investigate the effect of gastrocnemius(GCM) muscle length on the dynamic balance and antero-posterior pressure distribution of foot. Thirty subjects were recruited and each subject was classified with control experimental and control group according to GCM muscle length. The experimental group included subjects with shortness of GCM muscle length, the control group included subjects with normal length of GCM. The dynamic balance and antero-posterior pressure distribution of foot were measured by Biorescue equipment. To evaluate dynamic balance, we collected data of limit of stability in antero-posterior direction. We analyzed the data by using independent t-test. The alpha level was set 0.05. The results showed that the dynamic balance and antero-posterior pressure distribution of foot were significantly different between two groups (p<0.05). This study suggests that the shortness of GCM affects anterior limited of stability in dynamic balance and anterior pressure distribution of foot. Therefore, it is important to maintain optimal GCM muscle length for normal balance ability and prevention of musculoskeletal disease.

• Journal of Internet Computing and Services
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• v.1 no.2
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• pp.29-37
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• 2000

Asynchronous transfer mode is flexible to support multimedia communication services using asynchronous time-sharing and statistical multimedia techniques to the existing data communication area, ATM ABR service controls network traffic using feedback information on the network congestion situation in order to guarantee the demanded service qualities and the available cell rates, In this paper we apply the control method using queue length prediction to the formation of feedback information for more efficient ABR traffic control. If backward node receive the longer delayed feedback information on the impending congestion, the switch can be already congested from the uncontrolled arriving traffic and the fluctuation of queue length can be inefficiently high in the continuing time intervals, The feedback control method proposed in this paper predicts the queue length in the switch using the slope of queue length prediction function and queue length changes in time-series, The predicted congestion information is backward to the node, NLMS and neural network are used as the predictive control functions, and they are compared from performance on the queue length prediction. Simulation results show the efficiency of the proposed method compared to the feedback control method without the prediction, Therefore, we conclude that the efficient congestion and stability of the queue length controls are possible using the prediction scheme that can resolve the problems caused from the longer delays of the feedback information.

• Industrial Engineering and Management Systems
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• v.16 no.1
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• pp.109-117
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• 2017

In this article, a control chart based on multiple dependent (or deferred) state sampling for the gamma distributed quality characteristic is proposed using the gamma to normal transformation. The proposed control chart has two pairs of control limits, which can be determined by considering the in-control average run length (ARL). The shift in the scale parameter of a gamma distribution is considered and the out-of-control ARL is evaluated. The performance of the proposed chart has been shown for different levels of the parameters of the proposed control chart. It is also shown that the proposed chart is better than the Shewhart chart in terms of ARLs. A case study with a real data has been included for the practical usage of the proposed scheme.

• Industrial Engineering and Management Systems
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• v.11 no.4
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• pp.385-389
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• 2012

With the development of computer storage and the rapidly growing ability to process large amounts of data, the multivariate control charts have received an increasing attention. The existing univariate and multivariate control charts are a single hypothesis testing approach to process mean or variance by using a single statistic plot. This paper proposes a multiple hypothesis approach to developing a new multivariate control scheme. Plotted Hotelling's $T^2$ statistics are used for computing the corresponding p-values and the procedure for controlling the false discovery rate in multiple hypothesis testing is applied to the proposed control scheme. Some numerical simulations were carried out to compare the performance of the proposed control scheme with the ordinary multivariate Shewhart chart in terms of the average run length. The results show that the proposed control scheme outperforms the existing multivariate Shewhart chart for all mean shifts.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.2701-2706
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• 2003

This paper describes weld seam tracking and error compensation methods of automatic plasma arc welding system designed for the corrugation panel that consists of a linear section and a curved section with various curvatures. Realizing automatic welding system, we are faced with two problems. One is a precise seam tracking and the other is an arc length control. Due to the complexity of the panel shape, it is difficult to find a seam and operate a torch manually in the welding process. So, laser vision sensor for seam tracking is equipped for sensing the seam position and controlling the height of a torch automatically. To attain more precise measurement of an arc length, we measure the 3D shape of the panel and analyze error factors according to the various panel states and caused errors are predicted through the welding process. Using that result, compensation algorithm is added to that of arc length control and real time error compensation is achieved. The result shows that these two methods work effectively.

• International Journal of Control, Automation, and Systems
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• v.4 no.4
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• pp.486-494
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• 2006

In this paper, we present the complete isotropy analysis of a caster wheeled omnidirectional mobile robot (COMR) with nonredundant/redundant actuation. It is desirable for robust motion control to keep a COMR close to the isotropy but away from the singularity as much as possible. First, with the characteristic length introduced, the kinematic model of a COMR is obtained based on the orthogonal decomposition of the wheel velocities. Second, a general form of the isotropy conditions of a COMR is given in terms of physically meaningful vector quantities which specify the wheel configuration. Third, for all possible nonredundant and redundant actuation sets, the algebraic expressions of the isotropy conditions are derived so as to identify the isotropic configurations of a COMR. Fourth, the number of the isotropic configurations, the isotropic characteristic length, and the optimal initial configuration are discussed.

• Journal of Korea Multimedia Society
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• v.18 no.12
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• pp.1475-1482
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• 2015

In network routers, buffers are used to resolve congestion and reduce packet loss rate whenever congestion occurs at bottleneck link. Most of the existing methods to manage such buffers focus only on queue-length-based control as one loop which have some issues of low link utilization and system stability. In this paper, we propose a novel framework which exploits two-loop control method, e.g. queue-length and congestion window size, combined with optimal margin method to facilitate parameter choices. Simulation results in ns-2 demonstrate that bottleneck link performance can be improved with higher link utilization (85%) and shorter queue length (22%) than the current deployed scheme in commercial routers (RED and DropTail).

• Proceedings of the KIEE Conference
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• 2000.07d
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• pp.2516-2518
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• 2000

In order to reduce the trimming loss for water cooling zone next to finishing block mill in wire rolling, the operational data related to the crop length control of uncooled region was acquired and analyzed. The time deviation of water cooling spray nozzles and the immoderate preset length of uncooled wire rod result in the excessive trimming loss. Therefore, the preset length of uncooled wire rod at each cooling zone are established. The test results of #3 wire rolling mill turned out to be good enough to be expected to increase the ratio of products about 0.15% and establish operational standards of cooling zone.

• Journal of International Academy of Physical Therapy Research
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• v.12 no.2
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• pp.2354-2358
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• 2021

Background: Stroke is a neurological disorder characterized by an impaired static balance. A change in poor posture after stroke may worsen static balance. The balance control through an upright posture may include kinesiology taping of the middle back. Objectives: To investigated the effect of kinesiology taping of middle back on static balance in patients with stroke. Design: A randomized controlled trial. Methods: A total of 10 patients with stroke were divided into two groups. The experimental and control groups received kinesiology taping and placebo taping of the middle back, respectively. After 24 h, static balance (i.e., sway area and path length) was measured in closed eyes condition. Results: The experimental group (kinesiology taping group) showed a significant decrease in sway area and path length after the intervention. In addition, kinesiology taping group showed a significant decrease in sway area and path length compared to the control group. Conclusion: Kinesiology taping of the middle back can improve static balance in stroke patients.

• The Journal of Korean Physical Therapy
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• v.31 no.6
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• pp.368-371
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• 2019

Purpose: The purpose of this study was to investigate the effects of leg length discrepancy on kinematic changes of the pelvis and hip during gait. Methods: A total of ten healthy women with no history of neurological, musculoskeletal surgery or injuries, or pain in the lower limbs were recruited. They were assigned to two groups; the experimental group (LLD) consisting of five subjects leg length discrepancy of 10mm to 18mm and the control group (CON) consisting of five subjects leg length discrepancy of<10 mm. All participants were instructed to perform three walking trials for further analysis by using the Cortex 3.0 software program. Independent T-test and Mann-Whitney test were used to examine the effects of mild LLD on kinematic changes of the pelvis and hip during gait. Results: Angles of hip flexion, hip abduction, pelvic obliquity, and pelvic tilt in the experimental group were not significantly different compared to those of the control group. Conclusion: Mild leg length discrepancy induces kinematic changes in the lower limbs, including decreased hip flexion, increased hip abduction, and increased pelvic obliquity in the shorter limb, and increased hip adduction and increased pelvic obliquity in the longer limb. However, those changes were not significant.