• Journal of the Korean Wood Science and Technology
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• v.24 no.3
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• pp.65-71
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• 1996

In the design of wood structures, the consideration of the dynamic load effect has been increased. Generally, damping ratio is presented as the method of considering dynamic load effect. So, the relationship between joint type and damping ratio was investigated. It has been known that the joint extremely damp the dynamic load in wood structures. Static test was performed to determine the effects of nail size and friction area on joint strength and stiffness. Joint strength and stiffness were increased with nail size. However, the static properties of joint was not affected by friction area. Cyclic test was performed to determine the effects of nail size, friction area and load magnitude on damping ratio, Damping ratio was affected by all factors. Increasing the width of the bottom plate was suggested as the most adequate method to increase the damping ratio without the reduction of the static properties of the structures.

• Geomechanics and Engineering
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• v.30 no.4
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• pp.383-392
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• 2022

Although pipelines are composed of segmental tubes commonly connected by rubber gasket or push-in joints, current studies mainly simplified pipelines as continuous structures. Effects of joints on three-dimensional deformation mechanisms of existing pipelines due to tunnel excavation are not fully understood. By conducting three-dimensional numerical analyses, effects of pipeline burial depth, tunnel burial depth, volume loss, pipeline stiffness and joint stiffness on bending strain and joint rotation of existing pipelines are explored. By increasing pipeline burial depth or decreasing tunnel cover depth, tunneling-induced pipeline deformations are substantially increased. As tunnel volume loss varies from 0.5% to 3%, the maximum bending strains and joint rotation angles of discontinuous pipelines increase by 1.08 and 9.20 times, respectively. By increasing flexural stiffness of pipe segment, a dramatic increase in the maximum joint rotation angles is observed in discontinuous pipelines. Thus, the safety of existing discontinuous pipelines due to tunnel excavation is controlled by joint rotation rather than bending strain. By increasing joint stiffness ratio from 0.0 (i.e., completely flexible joints) to 1.0 (i.e., continuous pipelines), tunneling-induced maximum pipeline settlements decrease by 22.8%-34.7%. If a jointed pipeline is simplified as a continuous structure, tunneling-induced settlement is thus underestimated, but bending strain is grossly overestimated. Thus, joints should be directly simulated in the analysis of tunnel-soil-pipeline interaction.

• The Journal of Korean Physical Therapy
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• v.32 no.6
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• pp.354-358
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• 2020

Purpose: This study aimed to verify the effects of bridge exercise with resistance to one hip joint adductor muscle on the thickness of external and internal oblique abdominal muscles, transversus abdominis muscle, and erector spinae muscle. Methods: The subjects were divided into two exercise groups: 15 for Bridge Exercise Group (BEG) and 15 for One Hip joint Adduction Bridge Exercise Group (OHABEG). The study used an ultrasonic instrument to measure trunk muscle thickness. OHABEG performed a bridge exercise with one hip Joint adduction. BEG performed a bridge exercise without resistance. Results: The external oblique abdominal, internal oblique abdominal, and the transversus abdominis muscles showed a significant increase by period and time in intra-group interactions (p<0.05), while there was no significant difference in inter-group changes (p>0.05). The erector spinae muscle had a significant increase in each period (p<0.05) but no significant difference in time, intra-group interactions, and in inter-group changes (p>0.05). Conclusion: These results demonstrated that bridge exercise with one hip joint adduction had positive effects on trunk muscle thickness. These results confirm that a bridge exercise with one hip joint adduction has a positive effect on the muscle thickness of trunk, suggesting the possibility of using it as a rehabilitation treatment for a lumbar stabilization exercise and as a basic data.

• Journal of Acupuncture Research
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• v.34 no.4
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• pp.197-200
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• 2017

The effects of acupuncture treatment and taping therapy on a 22-year-old man who suffered from left foot pain due to Lisfranc joint injury were examined. Fractures of the first, second, and third metatarsal bones and a cuneiform bone were treated with acupuncture and taping therapy from March 24, 2017 to May 4, 2017. The patient was evaluated using the American Orthopaedic Foot & Ankle Society's Ankle-Hindfoot Scale. His Ankle-Hindfoot Score increased from 27 points pre-treatment to 65 points post-treatment. There were no side effects. While the improvement observed in this patient is encouraging, no definitive conclusion on the effects of acupuncture treatment and taping therapy on Lisfranc joint injuries can be reached without further large-scale study.

• Korea Trade Review
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• v.46 no.2
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• pp.161-175
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• 2021

The purpose of this study is to empirically analyze the effect of cultural distance between partner firms on international joint venture performance, focusing on the moderating effects of the conflict resolution techniques and the competitive relationship between partner firms. We tested hypotheses based on joint venture firms that were surveyed which formed by equity investment between Korean and foreign firms in the manufacturing industry. The empirical analysis results of this study are as follows. First, in international joint ventures, the cultural distance between partner firms was found to have a negative effect on the international joint venture performance, and the higher the cultural distance, the lower the joint venture performance. Second, it was found that constructive conflict resolution techniques weaken the negative impact of the cultural distance between partner firms in international joint ventures on the performance of international joint ventures. Third, competitive relationship between international joint venture partners showed no moderating effect on the relationship between cultural distance and international joint venture performance.

• The Journal of Korean Physical Therapy
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• v.19 no.4
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• pp.43-51
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• 2007

Purpose: The purpose of this study was to determine the effects on improvement of the range of motion in the TM joint. Methods: 26 subjects who have TM joint limitation were divided to passive movement group(n=13, $21.3{\pm}2.95$ years) and active movement group(n=13, $20.62{\pm}1.39$ years). All of the subjects were treated 5 to 10 minutes per one time, five times once a week for 4 weeks by the physical therapist. The open bite and cross bite were investigated at before, during(2 wks) and treatment(4 wks). Results: In order to assure the statistical significance of the result, a Repeated measures ANOVA were applied at the 0.05 level of the significance. There was a significant difference in terms of the rates of open bite mean change in within-open bite effects among pre-test, post-test 2weeks and post-test 4weeks in each group(P=0.029). There was no significant difference in the rates of mean change in between-open bite effects(P=0.441) but interactions between two types of effects(P=0.025) were statistical significance among pre-test, post-test 2 weeks and post-test 4 weeks in each group. There was no significant difference in the rates of mean change in within-close bite effects(P=0.112), between-cross bite(P=0.179) and interactions between the two types of effects(P=0.098) among pre-test, post-test 2 weeks and post-test 4 weeks in each group. Conclusion: The results of this study showed that passive movement and active movement were effect on increase of TM joint ROM about open bite and cross bite.

• Journal of Welding and Joining
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• v.16 no.4
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• pp.109-116
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• 1998

The three-dimensional profile of a solder fillet is predicted by minimizing the surface tension and gravity energies of the solder joint using finite element modeling. Geometric complexity stemming from the inclined plane of the gullwing lead is resolved by employing three element types. These element types are used to describe the joint profile formed on the vertical, inclined and interfacial planes. The predicted solder joint profiles show good agreements with the experimental data provided that the solder volume is adjusted considering the wicking effects. Effects of the pad length, inclined lead angle and solder volume on joint profiles are also investigated.

• 제어로봇시스템학회:학술대회논문집
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• 1997.10a
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• pp.764-767
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• 1997

This paper presents the modulation of the dexterity of a parallel manipulator using joint freezing/releasing and joint unactuation/actuation. In this paper, individual limbs have redundant number of joints, and each joint can be frozen/released and unactuated/actuated, as needed. First, given a task, the restrictions on joint freezing and joint unactuation of a parallel manipulator are derived. Next, with/without joint freezing and/or joint unactuation, the kinematics of a parallel manipulator is formulated, based on which the manipulability ellipsoid is defined. The effects of joint freezing and joint unactuation on the manipulability are analyzed and compared. Finally, simulation results for a planar parallel manipulator are given. Joint mechanisms, such as joint freezing and joint unactuation, are rather simple to adopt into a parallel manipulator, but is quite effective to improve the task adaptability of the system.

• Physical Therapy Rehabilitation Science
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• v.10 no.4
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• pp.406-413
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• 2021

Objective: The purpose of this study was to investigate effects of taping technique applied to knee instability. Design: Cross sectional study. Methods: Twenty-six participants with knee instabilityparticipated in this study. They were randomly assigned to the Kinesio taping (KT) group (n=13) and the dynamic taping (DT) group (n=13). Both groups applied knee stabilization taping techniques. In order to compare the effects of each taping technique, the change in the landing error scoring system (LESS) and lower extremity joint angle wasrecorded before and after the intervention. Results: Both groups significantly decreased in the change before and after the LESS (p<0.05). At the joint angle of the lower extremities, KT group significantly reduced the valgus angle at the max knee flexion (p<0.05). In DT group knee joint flexion and hip joint flexion angles were significantly increased at foot contact (p<0.05). In max knee flexion, the knee joint flexion angle was significantly increased (p<0.05). In foot contact, max knee flexion, the knee joint valgus angle was significantly increased (p<0.05). DT group showed more significant changes in knee joint flexion angle at foot contact and hip joint flexion angle at max knee flexion. Conclusions: Dynamic taping is a clinically applicable intervention method for lowering the risk of non-contact injury in participants with knee instability and for knee stability during rehabilitation exercises.

• Journal of the Korea Safety Management & Science
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• v.14 no.4
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• pp.93-105
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• 2012

The purpose of this study was to investigate drivers' postures in different car pedal systems and skilled levels under fatigue. Twenty four subjects participated in this experiment. For three-dimensional analyses, six cameras (Proreflex MCU-240, Qualisys) were used to acquire raw data. The parameters were calculated and analyzed with Visual-3D. In conclusion, ROAs of two leg-pedal system were less than one leg pedal system by pattern analysis. Through statistical tests, skilled levels have effects on ROAs(X, Y, Z) of ankle joint at breaking a pedal and ROAs(Y, Z) of ankle joint at accelerating a pedal. Also, car pedal systems have effects on ROAs(Y, Z) of ankle joint, and ROA(Z) of knee joint at accelerating a pedal. In addition, skilled levels and car pedal systems (cross effects) have an effect on ROA(Z) of ankle joint. These findings suggested that we should improve a present single pedal system.