• Journal of the Korean Institute of Intelligent Systems
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• v.23 no.2
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• pp.172-177
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• 2013

With Brain Computer Interface (BCI) system, a person with disabled limb could use this direct brain signal like electroencephalography (EEG) to control a device such as the artifact arm. The precise force control for the artifact arm is necessary for this artificial limb system. To understand the relationship between control EEG signal and the gripping force of hands, We proposed a study by measuring EEG changes of three grades (25%, 50%, 75%) of hand grip MVC (Maximal Voluntary Contract). The acquired EEG signal was filtered to obtain power of three wave bands (alpha, beta, gamma) by using fast fourier transformation (FFT) and computed power spectrum. Then the power spectrum of three bands (alpha, beta and gamma) of three classes (MVC 25%, 50%, 75%) was classified by using PCA (Principal Component Analysis) and LDA (Linear Discriminant Analysis). The result showed that the power spectrum of EEG is increased at MVC 75% more than MVC 25%, and the correct classification rate was 52.03% for left hand and 77.7% for right hand.

• Journal of Biomedical Engineering Research
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• v.43 no.5
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• pp.361-368
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• 2022

The purpose of this study was to develop a hand rehabilitation training system for hemiplegic patients. We also tried to find out five hand postures (WF: Wrist Flexion, WE: Wrist Extension, BG: Ball Grip, HG: Hook Grip, RE: Rest) in real-time using multi-channel EMG-based deep learning. We performed a pre-processing method that converts to Spider Chart image data for the classification of hand movement from five test subjects (total 1,500 data sets) using Convolution Neural Networks (CNN) deep learning with an 8-channel armband. As a result of this study, the recognition accuracy was 92% for WF, 94% for WE, 76% for BG, 82% for HG, and 88% for RE. Also, ten physical therapists participated for the usability evaluation. The questionnaire consisted of 7 items of acceptance, interest, and satisfaction, and the mean and standard deviation were calculated by dividing each into a 5-point scale. As a result, high scores were obtained in immersion and interest in game (4.6±0.43), convenience of the device (4.9±0.30), and satisfaction after treatment (4.1±0.48). On the other hand, Conformity of intention for treatment (3.90±0.49) was relatively low. This is thought to be because the game play may be difficult depending on the degree of spasticity of the hemiplegic patient, and compensation may occur in patient with weakened target muscles. Therefore, it is necessary to develop a rehabilitation program suitable for the degree of disability of the patient.

• Journal of the Korean Society of Industry Convergence
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• v.4 no.4
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• pp.379-386
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• 2001

The lower toughness or brittle materials for mechanical test lead to the additional requirement that applied displacements be controlled with high resolution. Biaxial tension and shear tester using stepper motor with harmonic driver is shown. The device had to be high resolution so that the crack initiation process of slow extension and steady growth could be examined, Grip plates were connected to a linear bearing and actuator. The actuators consisted of stepper motors with harmonic driver connected to pre-loaded ball screw and nut assemblies. The encoders and motor controllers were connected to a personal computer so that arbitrary displacements histories could he prescribed in normal and tangential directions. The linear bearings were used to react loads perpendicular to their axes while allowing low friction, parallel movement of the attached grips. Load cells measured the reactions normal and tangential. the loads measured the reactions were recorded by the computer.

• Journal of Biosystems Engineering
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• v.25 no.1
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• pp.19-24
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• 2000

This study was carried out to develop gripper which to adaptive variable tray and to develop automatic transplanting system for seedling-production system between tray. This system consisted of five set of gripper and end-effector, a planting-width control unit, a tray transfer unit, and gripper moving device which move gripper between nursing tray and growing tray. This system used push-out rod to grasp plant instead of pull-out end -effector. Several types of fingers, which physically grip seedlings, were also developed and tested to ensure reliable transplanting operation of the gripper. The transplanting system detaches seedlings from a tray with push-o0ut rods, which were installed under the tray transfer unit. The performance of the transplanting system was evaluated by successive transplanting experiments. Using the best type of finger , the transplanting system produced 94.6% of transplanting success rate.

• Journal of Biosystems Engineering
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• v.25 no.1
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• pp.63-70
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• 2000

In Korea, researches for year-round leaf vegetables production system are in progress and the most of them are focused on environment control. Automation technologies for harvesting , transporting and grading need to be developed. This study was conducted to develop harvesting process automation system profitable to a competitive price. 1. Manipulator and end-effector are to be designed and fabricated , and fuzzy logic controller for controlling these are to be composed. 2. The entire system constructed is to be evaluated through a performance test. A robot system for harvesting a lettuce was developed. It was composed of a manipulator with 20DOF (degrees of freedom) an end-effector, a lettuce feeding conveyor , an air blower , a machine vision device, 6 photoelectric sensors and a fuzzy logic controller. A fuzzy logic control was applied to determined appropriate grip force on lettuce. Leaf area index and height index were used as input parameters, and voltage was used as output parameter for the fuzzy logic controller . Success rate of the lettuce harvesting system was 93.06% , and average harvesting time was about 5 seconds per lettuce.

• Journal of the Korea Convergence Society
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• v.11 no.8
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• pp.147-152
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• 2020

The purpose of this study was to develop an auxiliary device useful for promoting continued participation in the golf among young golfers and female beginner-level golfers who were gradually increasing in number but often losing interest in the golf and gave up playing golf due to difficulty with posture, boredom from golf itself, slow improvement of skill, etc., in the process of learning the golf. For that, a hardware device fitted with various sensors was attached to the lower part of golf club grip to develop a platform capable of collecting and transmitting the data on each golfer's swing posture, driving distance, etc. If a smartphone app, which can analyze and store those data, is developed and synchronized, each golfer's postures can be identified and golfers can correct the posture on their own. Moreover, the smartphone app provides the contents for self-comparison and comparison with others and will be able to infuse the beginner-level golfers with internal motivation for continued participation in the golfing exercise if the game-type elements are added.

• Journal of Bio-Environment Control
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• v.23 no.2
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• pp.123-130
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• 2014

Oriental melon (Cucumis melo var. makuwa) should be cultivated on the soil and be harvested. It is difficult to find because it is covered with leaves, and furthermore, it is very hard to grip it due to its climbing stems. This study developed and tested oriental melon harvesting robots such as an end-effector, manipulator and identification device. The end effector is divided into a gripper for harvest and a cutter for stems. In addition, it was designed to control the gripping and cutting forces so that the gripper could move four fingers at the same time and the cutter could move back and forth. The manipulator was designed to realize a 4-axis manipulator structure to combine orthogonal coordinate-type and shuttle-type manipulators with L-R type model to rotate based on the central axis. With regard to the identification device, oriental melon was identified using the primary identification global view camera device and secondary identification local view camera device and selected in the prediction of the sugar content or maturity. As a result of the performance test using this device, the average harvest time was 18.2 sec/ea, average pick-up rate was 91.4%, average damage rate was 8.2% and average sorting rate was 72.6%.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.19 no.3
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• pp.115-120
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• 2019

Hemiplegic patients who suffered from a stroke struggle with a deterioration in upper limb functions, which can both be psychologically and physically discomforting; this can also limit patients' daily tasks involving any upper limb motions. In this study, we developed an assistive device for hemiplegic patients to improve their upper limb functions. It was manufactured to train patients by using their grip strength and the range of motion of the arm. Furthermore, we produced game contents in virtual reality to induce users' immersion and interaction. It was configured as a multi-player game to help ease the mental burden of receiving the training alone, hence allowing the patient and the caregiver to join the rehabilitation training simultaneously. The assistive device and game contents developed in this study enables patients and caregivers to easily check the degree of improvements in upper limb function by viewing quantitative analysis and visualized results.

• Journal of Digital Convergence
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• v.17 no.3
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• pp.161-168
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• 2019

The purpose of this study analyze consumer usage characteristics and product development guide of electronic pen based on TAM theory(Davies, 1989). Research methods apply contents analysis(qualitative research) and Activity/Inactivity analysis of main consumer participation. Research results are as follows. Active consumer indicated 30-49 age, male, office job and research fellow. And they suggested stable power supply system, App connected pen function extension, add the modified pen function, advanced data recognition of pen, advanced take note ability and stable grip feeling of pen, selected line width, synchronization improvement with other smart device and charging function. These result indicated the importance product improvement diffusion factor of early market to main market. The future research of electric pen focused on different product strategy between electric pen and smart device connected electric pen.

• Journal of The Korean Society of Integrative Medicine
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• v.11 no.2
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• pp.49-60
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• 2023

Purpose : We aimed to evaluate the impact of a exercise with kinect-based mixed reality device (KMR) on physical function, upper extremity disability, fatigue, and quality of life in breast cancer survivors. We hypothesized that this exercise program would improve physical function, physical activity, fatigue, and quality of life. Methods : Thirty-nine breast cancer survivors were randomized to either the KMR exercise group (KE) or the home stretch group (HS). The KE participated in 8 weeks of exercise, exercising 3 times per week, while the HS performed 8 weeks of stretching exercises, also 3 times per week. Before and after the intervention period, participants underwent assessments of physical function, including body composition, chester step test (CST), and hand grip strength (HGS). Additionally, participants completed questionnaires including the international physical activity questionnaire (IPAQ), disabilities of the arm, shoulder and hand (DASH) questionnaire, and functional assessment of cancer therapy-breast (FACT-B) questionnaire to measure their physical activity levels, upper extremity disability, and quality of life, respectively. Results : Overall, significant improvements were observed in several shoulder movements, body weight, and physical activity, with no significant interaction effects between groups and time. Furthermore, there was a significant group by time interaction for body weight, left flexion, right flexion, right abduction, and left adduction, as well as for upper extremity disability (K-DASH) and quality of life (FACT-B). Conclusion : In conclusion, the KMR exercise program was found to be effective at improving physical function, upper extremity disability, quality of life, and overall well-being in breast cancer survivors. The significant improvements observed in multiple measures and the significant group by time interactions for various outcomes highlight the potential benefits of this KMR exercise program in promoting a better quality of life for breast cancer survivors.