• Journal of the Korea Concrete Institute
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• v.17 no.6 s.90
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• pp.947-953
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• 2005

Previous test results showed that the current ASTM(American Standard for Testing and Materials) grip adapter for GFRP(Glass Fiber Reinforced Polymer) rebar was not fully successful in developing the design tensile strength of GFRP rebars with reasonable accuracy. It is because the current ASTM grip adapter which is composed of a pair of rectangular metal blocks of which inner faces are grooved along the longitudinal direction does not take into account the various geometric characteristics of GFRP rebar such as surface treatment, shape of bar cross section as well as physical characteristics such as poisson effect, elastic modulus in the transverse direction and so on. The objective of this paper is to provide how to proportion the optimum diameter of inner groove in ASTM grip adapter to develop design tensile strength of GFRP rebar. The proportioning of inner groove in ASTM grip adapter is based on the force equilibrium of GFRP rebar between tensile capacity and minimum frictional resistance required along the grip adapter. The frictional resistance of grip adapter is calculated based on the compressive strain compatibility in radial direction induced by the difference between diameter of GFRP rebar and inner groove In ASTM grip. All testing procedures were made according to the CSA S806-02 recommendations. From the preliminary test results on round-type GFRP rebars, it was found that maximum tensile loads acquired under the same testing conditions is highly affected by the diameter of inner groove in ASTM grip adapter. The grip adapter with specific dimension proportioned by proposed method recorded the highest tensile strength among them.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.56 no.1
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• pp.214-221
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• 2007

This paper presents a myoelectric hand prosthesis(MHP) with two degree of freedom(2-DOF), which consists of a mechanical hand, a surface myoelectric sensor(SMES) for measuring myoelectric signal, a control system and a charging battery. The actuation for the 2-DOF hand functions such as grasping and wrist rotation was performed by two DC-motors, and controlled by myoelectric signal measured from the residual forearm muscle. The grip force of the MHP was automatically changed by a mechanical automatic speed reducer mounted on the hand. The skin interface of SMES was composed of the electrodes using the SUS440 metal in order to endure a wet condition due to the sweat. The sensor was embedded with a amplifier and a filter circuit for rejecting the offset voltage caused by power line noises. The control system was composed of the grip force sensor, the slip sensor, and the two controllers. The two controllers were made of a RISC-type microprocessor, and its software was executed on a real-time kernel. The control system used Force Sensing Resistors, FSR, as slip pick-ups at the fingertip of a thumb and the grip force information was obtained from a strain-gauge on the lever of the MHP. The experimental results were showed that the proposed control system is feasible for the MHP.

• The Journal of Korean Physical Therapy
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• v.23 no.6
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• pp.43-47
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• 2011

Purpose: The aim of this preliminary study was to use hand function tests to Hand dexterity levels provided by the type of compression garment and compression bandages in asymptomatic subjects and to collect baseline data for the comparison of hand functions in the patients with chronic arm lymphedema. Methods: The subjects of this study were 32 healthy volunteer female with a mean age of 45.8 years. Grip strength and hand functions were tested in three conditions-no compression, compression garment, and compression bandages-using the nine-hole peg test (NHPT), the box and block test (B&BT), Minnesota Manual Dexterity test (MMDT), and the hand-held Jamar dynamometer. Results: The grip strength was significantly low in the bandage condition (p<0.05). The performance in both compression groups (i.e., bandage and compression garment) decreased as the thickness of the compression material increased (p<0.05). Conclusion: The findings of this study suggest that grip strength and hand function scores are influenced by the characteristics of the compression applied. Future study is needed to determine the level of hand function between patients with chronic arm lymphedema and healthy individuals.

• The Journal of the Korea Contents Association
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• v.9 no.7
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• pp.202-210
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• 2009

This study was carried out to identify the factors which correlated with upper limb function after stroke and to analyze the effect of related factors on upper limb function. The 100 stroke patients(MMSE-K>24) were participated. The upper limb function according to gender, hand dominance, stroke type, affected location, site of paralysis, speech disorder showed no significant difference, and show significant difference according to shoulder subluxation. The upper limb muscle strength(Manual Muscle Testing), proprioception, muscle tone(Modified Ashworth Scale), grip strength(Dynamometer), paint (Visual Analog Scale) showed significant correlations with upper limb function. These predictors explained 77.6% of the upper limb function and the most significant affecting factor of upper limb function was upper limb muscle strength. In conclusion, the upper limb muscle strengthening will be effective strategy to improving the upper limb function and considering the proprioception, muscle tone, grip strength, pain, subluxation will be helpful to develop the strategies.

• Science of Emotion and Sensibility
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• v.7 no.1
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• pp.1-7
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• 2004

This study aims to validate the effectiveness of CAVE system with an Arm-Master in the evaluation of virtual prototypes. A virtual kitchen with a refrigerator was presented in the CAVE system. Subjects put in and pull out virtual objects by using the Arm-Master. Twelve subjects, six males and six females, participated in the six experimental conditions : three types of refrigerator door grips and two reaction forces. After each trial, subjects evaluated a door grip of the virtual refrigerator in terms of easiness of operation, similarity in force, presence etc. The results show the mean values of vortical-type door grips are greater than the horizontal pocket-type door grip. Also the subjects preferred 5N in the reaction force of the Arm-Master rather than 15 N when they open and close virtual door. Unexpectedly, female subjects significantly marked low scores in the evaluation terms compared ruth mali subjects. It explains the Arm-Master should be modified much more if it works effectively in design evaluation.

• Journal of the Korean Society of Industry Convergence
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• v.23 no.2_2
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• pp.313-321
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• 2020

In this paper, two types of linear actuation methods for the previously proposed adaptive gripper are presented, which includes actual parallelogram inside a five-bar mechanism and has the advantages of smaller actuation torque and larger stroke over the commercial adaptive gripper by RobotiQ. The forward/inverse kinematics and statics analyses for two types of linear actuations are derived. From the inverse kinematics and statics analyses, linear actuation type I is selected and the gripper prototype is designed.

• PNF and Movement
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• v.18 no.1
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• pp.1-10
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• 2020

Purpose: This study was conducted to examine the effects of a PNF intervention using elastic bands on edema, range of motion (ROM), and pain in post-mastectomy patients with upper limb lymphedema, according to their hand grip type. Methods: The subjects were 14 female patients who were at Stage II lymphedema after undergoing mastectomy for Stage II breast cancer. They were randomly divided into an experimental group (n =7) and a control group (n = 7). Both groups participated in a treatment program four times (one time under the therapist's instructions and three times as self-exercise) a week for 4 weeks. Both groups repeated an upper limb PNF pattern exercise for 30 min using elastic bands after receiving a manual lymph drainage treatment for 1 hour. Here, subjects in the experimental group performed the PNF exercise with an open-hand grip by putting their hands into the loops of elastic bands and keeping their fingers spread out. Subjects in the control group performed the PNF exercise with a closed-hand grip by holding the loops of elastic bands with their fingers. In both groups, the subjects' edema, ROM, and pain levels were measured before the intervention and 2, 3 and 4 weeks after the intervention. Results: As a result of the experiment, both groups demonstrated edema reductions, ROM increases, and pain reductions in four areas of the upper limbs. Notably, the experimental group exhibited larger ROM increases in flexion, extension, and abduction as well as greater edema and pain reductions than the control group. In particular, the most significant effects were found in the elbow of the four upper limb areas for edema reductions and in extension for ROM increases. Conclusion: The present study indicates that exercise therapy-based approaches using elastic bands in post-mastectomy patients with upper limb lymphedema can have different effects depending on the type of hand grip (open or closed), which is the body's most distal part. Therefore, these approaches should be based on the conditions of the distal parts of the patient's body for their effective applications in clinical practice.

• Journal of the Korean Society of Industry Convergence
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• v.25 no.2_1
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• pp.185-193
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• 2022

For grippers of industrial robots, parallel grippers and multi-function finger grippers are used. The former has the advantage of low cost but has the disadvantage of low precision, and the latter has the advantage of excellent precision but has the disadvantage of being expensive. In this paper, we developed a grip that can detects the various shapes of the object to be gripped on the gripper surface by using mesured pressure information frome Veloset Sheet sensor so that the gripper can be gripped without deforming the surface of the gripper. Also we did not only developed the array type gripper and 4 array type grippers (ATG), but also confirmed the usefulness of array type gripper developed in this study according to the 4 predefined evaluation criteria

• Physical Therapy Korea
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• v.20 no.2
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• pp.28-37
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• 2013

This study examined differences in the activity of upper limb muscles according to how an ultrasound head is gripped. Twenty-two adult males were participated in the study. Each participant was asked to apply ultrasound treatment on to a lump of pork meat by two different ultrasound head grip patterns: spherical and cylindrical grips. Muscle activity was measured in the extensor carpi radialis longus (ECRL), flexor carpi ulnaris (FCU), and pronator teres (PT), triceps brachii (TB), middle deltoid (MD), and upper trapezius (UT) muscles. There were no significant differences in the EMG signals of any muscle according to the ultrasound head grip pattern (p>.05). There were significant differences in the EMG signal of each type of muscle (p<.05). The EMG signal of UT was the lowest and that of TB was lower than ECRL and FCU. There were interactions between ECRL and FCU, between ECRL and PT, between FCU and ECRL, and between FCU and MD. The EMG signal of ECRL using the cylindrical head was low and that of FCU with the cylindrical head was high, while the opposite was the case with the spherical head ($p_{adj}$ <.05/15). The results of this study indicate that the wrist muscles worked actively when the participants applied ultrasound therapy using both spherical and cylindrical heads. A spherical head might induce imbalanced muscle activity among the wrist muscles, leading to deviation of the wrist joint. Therefore, the cylindrical head is recommended for ultrasound therapy because it produced a constant, repeated force.

• Women's Health Nursing
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• v.20 no.4
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• pp.297-308
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• 2014

Purpose: The purpose of this study was to review the effects of physical activity on musculoskeletal outcomes in older Koreans. Methods: Experimental studies were retrieved from the search engines (PubMed, CINAHL, PsycINFO, Cochrane, RISS, KISS, and KoreaMed). The selected studies for analysis were 27 articles of musculoskeletal outcomes (gait, muscle strength, flexibility, balance, grip strength, endurance, body fat, and weight) from 515 articles. Results: The most common type of physical activity was a resistance exercise. There were significant improvements in gait (71.4%), muscle strength (86.7%), flexibility (63.6%), balance (72.2%), grip strength (71.4%), endurance (71.4%), body fat (57.1%), and weight (28.6%). The activity programs that apply over 150 minutes a week showed greater improvement of 69.5% than 65.0% from those did not meet the guidelines totally. Conclusion: Based on the review, we conclude that regular physical activity in the elderly may improve the musculoskeletal outcomes. To be more effective programs, it is necessary to meet the guidelines of 150 minutes a week or 30 minutes of moderate-intensity activities on 5 days per week for the elderly.