• Journal of Korea Multimedia Society
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• v.16 no.2
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• pp.213-225
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• 2013

This paper proposes a design method of ball-plate robot controller using single camera and two motors to balance the ball on plate and reduce steady state control error. To design the ball-plate system, it is necessary to observe state of the ball and maintain balance of the plate. The state of the ball is tracked by using the CAMShift algorithm and position error of the ball is compensated by the Kalman filter. Balance of the plate is controlled by driving two motors and we used DC motors which has smaller measurement error. Due to surface condition of the plate or tracking error of ball's position, there are small errors remained. These errors are accumulated and disturb maintaining balance of the ball. To handle the problem, we propose a controller supplemented with an integrator.

• Journal of Korean Society of Water and Wastewater
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• v.29 no.3
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• pp.427-436
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• 2015

Developing two process models to simulate wastewater treatment process is needed to draw a comparison between measured BOD data and estimated process model data: a mathematical model based on the process mass-balance and an ANN (artificial neural network) model. Those two types of simulator can fit well in terms of effluent BOD data, which models are formulated based on the distinctive five parameters: influent flow rate, effluent flow rate, influent BOD concentration, biomass concentration, and returned sludge percentage. The structuralized mass-balance model and ANN modeI with seasonal periods can estimate data set more precisely, and changing optimization algorithm for the penalty could be a useful option to tune up the process behavior estimations. An complex model such as ANN model coupled with mass-balance equation will be required to simulate process dynamics more accurately.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2013.05a
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• pp.1465-1466
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• 2013

• Journal of Korean Physical Therapy Science
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• v.28 no.2
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• pp.65-74
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• 2021

Background: The purpose of this study was investigated of effect of neuromuscular electrical stimulation combined with mirror therapy on static balance, weight support and ankle movement incline with chronic stroke patients. Design: Two-group pretest-posttest design. Methods: Thirty chronic stroke patients participated in this study. The study design is a two-group pretest-posttest design. A total of 30 people participated in the study, and 15 people were each assigned to the experimental group and control group. Experimental group received neuromuscular electrical stimulation combined with mirror therapy 30 minutes, and conventional physical therapy 30 minutes. Control group received conventional physical therapy 30 minutes. Both groups were conducted 5 times a week for 4 weeks. static balance and weight support was measured by force plate and ankle movement incline was measured by goniometer. Results: As a result of comparing the static balance, weight support and ankle movement incline change between experimental group and control group, statistically significant differences were found in all variables (p<.05). In the evaluation before and after the intervention, there was a statistically significant difference in all variables in the experimental group (p<.05), but there was no statistically significant difference in the control group (p>.05). Conclusion: Neuromuscular electrical stimulation combined with mirror therapy intervention improves static balance, increase paretic side weight support and ankle movement incline in chronic stroke patients. It could be an effective intervention for improve static balance, weight support and ankle movement for chronic stroke patients.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.17 no.5
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• pp.123-130
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• 2018

In this study, the optimum design of mold feed systems is determined for plug cover housing (PCH), which is a cover-assembly product that protects the wiring of automobile connectors. The design goal is to achieve the filling balance of the resin in the left and right covers while avoiding the occurrence of weld lines in the hinge as much as possible. For the optimization, an orthogonal array experiment and a main effect analysis of the design factors are performed, and the factors that cause the interactions with the two design characteristics are selected as the design variables. We present some design alternatives, i.e., some combinations of the design variables, and analyze the filling-simulation results, expected molding risk, and cost economics to select an optimum design solution among the design alternatives. In the optimal solution, the weld line is generated at a position outside the hinge, and the filling balance is also acceptable, showing that both design goals can be satisfied simultaneously despite conflicting with each other.

• Physical Therapy Rehabilitation Science
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• v.9 no.2
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• pp.67-73
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• 2020

Objective: The purpose of this study was determine the effect of Balance Trainer training with Transcutaneous Electrical Nerve Stimulation (TENS) on spasticity and balance in persons with chronic stroke. Design: Randomized controlled trial. Methods: A total of 30 subjects with hemiparetic stroke were recruited and randomly divided into the Balance Trainer training with TENS group (n=15) and Balance Trainer training with placebo TENS group (n=15). The Balance Trainer training with TENS group practiced additional Balance Trainer training with TENS for 30 minutes a day, 5 days per a week during 4 weeks and the Balance Trainer training with placebo TENS group practiced additional Balance Trainer training with placebo TENS for the same period. Spasticity and balance were assessed by ability (static balance, dynamic balance) and were measured before and after the 4-week programs. Results: The result of spasticity and dynamic balance were improved significantly in both groups (p<0.05). The Balance Trainer training with TENS group showed significantly greater improvement in spasticity of the gastrocnemius & dynamic balance, compared to the Balance Trainer training with placebo TENS group (p<0.05). The Balance trainer training with TENS group showed a significant improvement in static balance, especially during the eye-closed condition (p<0.05). Conclusions: The Balance Trainer training with TENS was effective in improving spasticity and balance in subjects with chronic stroke. Based on these results, it is suggested that Balance Trainer training with TENS could clinically be used more actively in conjunction with conventional physical therapy.

• Journal of the Institute of Electronics and Information Engineers
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• v.51 no.4
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• pp.27-32
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• 2014

Two-dimensional hybrid codewords are generated by using each row of identity matrix for spatial encoding and nonideal symmetric balance incomplete block design(BIBD) code for spectral encoding. This spatial/spectral optical code-division multiple-access (OCDMA) network uses single-balanced detectors to abstract the desired information bits and to eliminate the multiple-access interference(MAI). Analytical results show that the number of simultaneous users increases significantly by using the proposed hybrid codes.

• Polymer(Korea)
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• v.33 no.6
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• pp.561-568
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• 2009

Small injection molded articles are generally molded by multi-cavity injection molding. The most important thing in multi-cavity molding is flow imbalance among the cavities because it affects the physical property and the quality of products. The cavity filling balance can be achieved by flow balance in the runner through the thermal balance. In this study, novel screw type runner or helical type runner has been developed for the flow balance in the runner and performed experiment and computer simulation. Flow balance has been observed using various screw type runners for several resins such as amorphous and crystalline polymers including low and high viscosities grades. Flow balance experiments have been performed for various injection speeds since the flow balance can be affected by injection speed among the injection conditions. Experimental results have been compared with computational results and they showed good agreement. The cavity filling balance can be achieved by the screw runner where the temperature distribution is uniform through the circulation flow along the screw channel in the screw runner. It has been verified that the novel screw runner is very effective device in flow balance in the multi-cavity injection molding. cavity filling imbalance, multi-cavity injection molding, runner design, screw runner, thermal balance.

• Journal of Korean Physical Therapy Science
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• v.29 no.2
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• pp.1-13
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• 2022

Background: This research was conducted to understand balance training in trunk control, balance, and walking in stroke patients. Design: Randomized controlled trial. Methods: The subjects included 40 stroke patients, of whom 20 undertook balance training using visual information and the other 20 undertook balance training using balance boards. Using visual feedback, the balance training group used a training program within the static balanced evaluation tool, while the balance training group trained using a balance board. All subjects underwent 20 mins of neurodevelopmental treatment, and both target groups underwent 10 mins each of balance training by using either visual feedback or a balance board. The treatment period lasted a total of 4 weeks, twice a day. Trunk control before and after training was evaluated with the Trunk Impairment Scale. Balance capability was assessed by the Berg Balance Scale, Functional Reach Test, Timed Up and Go test, and Static balance measurement tool. Walking capacity was measured using gait measuring equipment, and cadence and velocity were measured. Results: Both groups showed a significant improvement in their interstitial control, balance, and gait ability after the experiments compared to before the experiments (p<0.05). The difference between the two groups was not significant. The visual feedback balance training group showed a more substantial improvement than the balance board training group. Conclusion: In this study, we found that the balance training combined with visual feedback contributes to improving trunk control, balance, and gait in patients with hemiplegia due to stroke. In addition to this, I believe that balanced training combined with visual feedback can be used as a training method when considering patients who lack interstitial control, balance, and gait ability.

• Journal of Korean Academy of Nursing
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• v.44 no.6
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• pp.697-707
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• 2014

Purpose: The purposes of this study was to develop a comprehensive community-based fall prevention program and to test the effects of the program on the muscle strength, postural balance and fall efficacy for elderly people. Methods: The design of this study was a nonequivalent control group pretest-posttest design. There were 28 participants in the experimental group and 29 in the control group. The program consisted of balance exercises, elastic resistance exercises and prevention education. The program was provided five times a week for 8 weeks and each session lasted 90 minutes. Data were analyzed using ${\chi}^2$-test, independent t-test and paired t-test using the SPSS program. Results: Muscle strength of the lower extremities, postural balance and fall efficacy scores significantly improved in the experimental group compared to the control group. Conclusion: These results suggest that this program can improve lower extremity muscle strength, postural balance and fall efficacy in elders. Therefore, this program is recommended for use in fall prevention programs for elders living in the community.