• The Journal of Korean Physical Therapy
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• v.34 no.2
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• pp.57-62
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• 2022

Purpose: The purpose of this study was to determine the effects of bilateral visual feedback training with visual targets on the postural balance and fall efficacy of stroke patients with hemiparesis. Methods: A total of 24 stroke patients with hemiparesis were randomly assigned to either a bilateral visual feedback training (BVFT, n=8) group, unilateral visual feedback training (UVFT, n=8) group, or a control group (n=8). The BVFT and UVFT groups performed weight-bearing training on the bilateral (less-affected and affected side) or unilateral side (affected side) with visual feedback using visual targets. The control group performed squat training without visual feedback using visual targets. The training program was conducted in the form of 3 sets a day, 3 times a week, for 4 weeks. The participants were evaluated using the Berg balance scale (BBS), lateral reaching test (LRT), timed up and go test (TUG), and the activities-specific balance confidence scale (ABC). Results: In the intra-group comparison after the intervention, the BVFT group showed a significant difference in the BBS, TUG, affected and less-affected side LRT, and ABC (p<0.05). The UVFT group showed a significant difference in the BBS and ABC (p<0.05). In the inter-group comparison after the intervention, the BVFT group showed significant improvements in their BBS, affected side LRT, and TUG, when compared to the control group (p<0.05). Conclusion: These findings show that bilateral visual feedback training with visual targets during bilateral weight-bearing exercises can improve the postural balance function in stroke patients.

• Physical Therapy Rehabilitation Science
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• v.9 no.4
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• pp.287-294
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• 2020

Objective: This study aimed to investigate the effects of an ultrasound-based bar graph proportional to the quadriceps muscle thickness as a real-time visual feedback training tool in the elderly. Design: Cross-sectional study. Methods: Twenty-four elderly persons participated in this study and were randomly divided into three groups: oral training group (n=8, group 1), ultrasound imaging group (n=8, group 2), and graph group (n=8, group 3). In the pre condition, all participants performed maximal voluntary isometric contraction (MVIC) of the quadriceps with knee extension three times with oral training. In the post condition, group 1 performed MVIC of the quadriceps with oral training, group 2 performed MVIC of the quadriceps with real-time visual feedback using ultrasound imaging, and group 3 performed MVIC of the quadriceps with real-time visual feedback using a bar graph proportional to the quadriceps muscle thickness, three times for all groups. Muscle thickness, activity (mean, peak), tone, stiffness, logarithmic decrement, relaxation, and creep were measured in both conditions in all participants. Results: Visual feedback with a bar graph showed significant effects on muscle thickness, mean muscle activity, and peak muscle activity compared with oral training and visual feedback with ultrasound imaging (p<0.05). Conclusions: Isometric training of the quadriceps with real-time visual feedback using a bar graph proportional to the quadriceps muscle thickness may be more effective than other methods in improving muscle thickness and muscle activity. This study presented a tool that can help increase muscle thickness in the elderly.

• Smart Media Journal
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• v.13 no.5
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• pp.62-71
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• 2024

This study conducted a team-based CPR simulation with 32 fourth-year emergency rescue students to determine the effectiveness of training feedback using body cameras used at emergency rescue sites, and measured awareness, training feedback effectiveness, and satisfactio+n before and after body camera feedback. , preferences and difficulties in using body camera devices were identified. Data analysis was performed using SPSS 27.0 program, including descriptive statistics, frequency analysis, paried t-test, and Wilcoxon signed rank test. As a result of the study, the perception of body camera use showed a positive change from 3.73±0.62 points to 4.45±0.54 points, and a positive satisfaction level of 3.98±0.51 was shown (p<.001). Additionally, there was a significant increase in self-check accuracy and performance score after body camera feedback (p<.001). Therefore, during team-based simulation resuscitation training, positive feedback effects in improving self-inspection ability and performance can be achieved by watching body camera videos and using self-checklists without direct feedback from the instructor.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2001.10a
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• pp.57-61
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• 2001

A conceptional framework is proposed in which a general feedback predictive controller is taken to be a feedback interconnection of controller and GPC (General predictive Control). Numerical example are included to illustrate the procedure and to show the performance of the control system.

• ETRI Journal
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• v.34 no.5
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• pp.763-766
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• 2012

This letter proposes an iterative multimode precoding scheme with limited feedback for nonreciprocal MIMO interference channels. Based on analysis of game theory, we model the iterative multimode precoding as a noncooperative game with a finite set of strategies. Numerical results are presented to verify the sum rate performance of the proposed scheme.

• 전기의세계
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• v.20 no.1
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• pp.45-47
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• 1971

공업전자의 현황과 전망에서는 SCR을 주축으로 한 반도체소자를 이용한 Energy변환 및 제어의 분야의 반도체소자를 매개로한 Energy변환과 제어 및 기계의 전자화된 조절장치를 체계화한 전기공학의 분야에 대해 설명했으며, 우주통신과 우주선 추적에서는 아폴로 S대통일계통, Goddard식 거리속도추적계통, 중계위성에 대해 설명했으며 Feedback inbiological systmems lecture notes에서는 Familar definition of Feedback, Definition of Control Feedback에 대해 논하였다.

• Proceedings of the Korea Society of Design Studies Conference
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• 2005.10a
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• pp.26-27
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• 2005

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.235-235
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• 2000

This paper proposes a tole force feedback control through internet systems. The system consists of joystick, solver, client, robot, and internet. The main contribution of this work is the implementation of the system rather than theoretical analysis. The time delay problems will be considered next step.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.209-209
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• 2000

In this paper, we show that some of 2- or higher-dimensional systems cannot be asymptotically stabilized on the constrained asymptotically stabilizable set via linear feedback.

• 전기의세계
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• v.30 no.2
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• pp.86-96
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• 1981

The problem of incomplet state feedback began to appear late in60's and early in 70's. This was motivated by inability to measure all the states of the system in practice. This survey paper traces the early developments in the subject through to the most recent achievement of gain-determining, pole-assignment, stabilization, and low sensitivity system design with output feedback.