• Journal of Advanced Marine Engineering and Technology
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• v.31 no.4
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• pp.394-400
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• 2007

The properties and weldability of lap joints by PFSW with 1050 Al sheet was investigated according to tool shape. dimension and welding condition. Tensile shear test was carried out for lap jointed specimen, and the hardness in the joint regions was examined. Moreover interfacial joining length, metallograph and failure location of the lap-jointed cross section were discussed. Two tool types were a simple cylindrical type and a notched cylindrical type. Under joining conditions such as plunging depth of 2.2mm. rotating speed of 1600rpm and dwelling time of 3s, the tensile shear strength of lap-jointed specimen by the notched type tool was superior to that by simple cylindrical type tool. The maximum tensile shear load of lap jointed specimen was 5807N. Optimal dimensions of the notched type tool were as follows : diameters of the shoulder and pin were $18{\phi}mm$ and $10{\phi}mm$, and pin length was 2.2mm.

• Physical Therapy Korea
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• v.28 no.1
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• pp.13-17
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• 2021

A normal range of motion is essential for performing activities of daily living. The capsular pattern is the proportional motion restriction in range of motion during passive exercises due to tightness of the joint capsule. Although the capsular pattern is widely referred to in clinical practice, there is no scientific evidence to support the concept. In this review, the appropriateness of the capsular pattern for evaluation of joint pathology was assessed. In the Textbook of Orthopaedic Medicine written by Cyriax, the capsular pattern did not specify how much reduction in angular motion is considered motion restriction. As the definition proposed initially was unclear, different methods have been used in previous studies investigating capsular pattern. In addition, the capsular pattern described all the major joints of the human body, but only the hip joint, knee joint, and shoulder joint were studied in experimental studies. Sensitivity and specificity were reported in one study and were meaningful in specific pathologies (loss of extension to loss of flexion). There was no consensus on the reliability and validity. In summary, the capsular pattern suggested by Cyriax or Kaltenborn is not supported or applies only to certain conditions. Various components around a joint complement each other and provide stability to the joint. It is recommended that the therapist perform multiple assessments rather than rely on a single assessment when evaluating joints.

• Journal of the Korea Safety Management & Science
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• v.25 no.2
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• pp.107-111
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• 2023

This study aims to empirically investigate effects of motion repetition and external load according to joint motion on discomfort through an experiment. Eighteen college students (female: 9; male: 9) participated in an experiment measuring perceived discomfort using the Borg CR10. Joint(wrist, elbow, shoulder and trunk) motion, its repetition and external load were adopted as independent variables. The results showed that all three independent variables were statistically significant on discomfort. Participants' sex also significantly affected discomfort obtained in the experiment. While the interactions of joint motion and repetition, and joint motion and external load were not significant at α = 0.05, that of motion repetition and external load was significant. Based on the experimental results, four regression equations by the joints involved were presented, which could be used as a tool for evaluating postural loads by the joints. It may be postulated that based on the results of this study, scoring systems of RULA and REBA, and those of OWAS and REBA underestimates effects of motion repetition and external load, respectively. It is expected that the results of this study will be used as a basic data for developing an observational method properly reflecting the effects of motion repetition and external load.

• Korean Journal of Applied Biomechanics
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• v.18 no.1
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• pp.137-146
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• 2008

The purpose of this study is to examine the causes of errors from EGR posture on the balance beam, which is bending flick-flack salto backward stretched national team players through kinematic analysis, and present training methods for them so as to provide scientifically useful information to coaches and athlete. Findings from this study are summarized below. The most important factors that affect the errors in boyd center position and speed change were the speed change of left and right body centers and the horizontal and vertical speed changes. The left and right acceleration changes were greater in failed posture than in successful posture. The horizontal and vertical accelerations in E3 and E5 were the key factors that affected the backward somersault and landing. The angular speed changes which varied between success and failure were notable in head and shoulder joints. In individual results. The section when the angular speeds of head and shoulder joint must be the greatest was E4. In this section, when the body is extending instantly in a bent posture, increasing the angular speeds of head, shoulder and hip joints can improve the duration of staying in the air and the rotation radius of a somersault.

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.1
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• pp.143-150
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• 2013

The aim of the pilot study was to evaluate slaughter characteristics and carcass composition of indigenous long fat tailed sheep and Small East African goats purchased from the auction markets slaughtered at 1.5 to 2 yrs of age and 20 kg to 25 kg live weight. The animals were slaughtered according to halal standard procedures. The left half carcasses were jointed into eight wholesale joints, and dissected into muscles, fat and bone, which were weighed separately. Sheep had greater (p<0.05) slaughter BW (22.29 kg vs 20.50 kg) and empty BW (20.17 kg vs 18.67 kg) than goats (p<0.05). Dressing percentages were lower (p<0.001) in sheep than goats when carcass weight was expressed as percentage of slaughter BW (42.31% and 47.15%) and empty BW (46.75% and 51.79%). Sheep carcasses had lower (p<0.001) proportion (66.18% vs 71.64%) of muscles and higher (p<0.001) proportion of fat (7.41% vs 3.44%) than goat carcasses. Sheep had proportionally lighter (p<0.001) shoulder (18.89% vs 22.68%) and heavier (p<0.05) proportion of chump (7.916% vs 6.76%) and main rib (8.12% vs 7.07%). Sheep had more (p<0.001) muscles in the leg (28.83% vs 27.08%) and main rib (7.62% vs 6.36%) than goats. Sheep had less (p<0.001) muscles (20.28% vs 23.56%) in shoulder joints when expressed as percentage of total muscle of carcasses. It is concluded that there are differences in sheep and goat both in terms of carcass and joint yields and composition. The present study also implies that there is need to consider setting different meat cuts and prices for these cuts when one takes into account the differences in muscle distribution within joints in sheep and goats.

• Clinics in Shoulder and Elbow
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• v.13 no.2
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• pp.286-292
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• 2010

Purpose: Stability of joints and maintenance of range of motion are needed for optimum function. The most common complaint about the elbow joint is joint stiffness. Recent articles have reported good outcomes in the treatment of stiff elbow joints. However, deciding which procedure to use is always difficult. Materials and Methods: Morrey et al. reported that the functional range of motion of the elbow joint is $30-130^{\circ}$ of flexion-extension and $50^{\circ}C$ of supination and pronation. About 90% of daily activities are done using this range of motion. Stiff elbow joints can be classified according to the traumatic events that caused the problem or the location of the main pathology. Intraarticular pathology includes severe articular mismatch, intraarticular adhesions, loss of articular cartilage, mechanical blockade by osteophytes, loose bodies, and hypertrophied synovium. Extraarticular pathology includes severe capsular adhesion due to the trauma or to dislocation, contracture of the collateral ligaments or muscles, bony bridge. Results and Conclusions: The main pathology underlying the loss of extension is the fibrous contracture of the anterior capsule. In this pathology, an anterior capsulectomy would be helpful. The main pathology underlying the loss of flexion is the contracture of the posterior band of medial collateral ligament.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.22 no.3
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• pp.294-300
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• 2000

Purpose: The aim of this study was to find the clinical characteristics of the patients who had temporomandibular joint internal derangement(ID) with disc adhesion(adhesion group) compared to only disc displacement without disc adhesion, perforation, hyperemia, and so on(ID group). Materials and methods: Thirty seven joints were included in adhesion group and 54 joints in ID group of all 174 patients(174 joints) treated surgically and had been checked periodically over 12 months at TMJ clinic of Yongdong Severance Hospital, Yonsei University, between 1992 and 1997. Mouth opening range, pain during mouth opening and biting, headache, neck/shoulder pain and TMJ sound were checked his/her every visit before and after surgery. Results: The maximum mouth opening was improved significantly after postoperative 3 months in two groups(p<0.01), but adhesion group was less improved. Pain during mouth opening was improved significantly over 3 months after surgery in adhesion group(p<0.01), but in ID group 1 month after surgery. Biting pain was improved and maintained it after surgery and not significant difference between two groups. Headache and neck/shoulder pain were much improved after surgery(p<0.01), but slight relapse was found in adhesion group after 12 months. TMJ sound was more found in adhesion group after 1 month(p<0.05), but after 3 months, no significant difference was found between two groups. Conclusions: The postoperative results of adhesion group were worse than ID group. Therefore, it is considered more carefully to diagnose and treat in cases of internal derangement with adhesion.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.3
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• pp.614-618
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• 2018

The changes in the mechanical properties according to the width of the tool shoulder, rotation speed and moving speed in friction stir welding (FSW) are evaluated using Al 6061-T6. The results indicated that the tensile strength value increases with increasing rotation speed. The higher the moving speed of the tool shoulder, the lower the tensile strength, regardless of the tool type. A higher tensile strength value was generally obtained with a tool shoulder diameter of 12mm (TSD12) than with 8mm. When the moving and rotation speeds exceed a limiting value, a stabilization stage is reached, in which (the tool shoulder diameter?) no longer affects the material properties. At a tool shoulder diameter of 8mm (TSD8), the material properties are decreased and the mixture of material in the welding area is incomplete in comparison with the tool type of TSD12. The tensile strength value is decreased at a rotation speed of 1500 rpm. As a result, a rotation speed higher than the threshold value is needed in order for and the transition temperature to be reached, which allows the complete mixing of the material in the welding area.

• Journal of Digital Convergence
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• v.10 no.11
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• pp.551-558
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• 2012

Objectives: The purpose of this study was to determine whether the sacrooccipital category II blocking technique may improve abdominal muscle endurance and alleviate shoulder pain caused by pelvic tilting. Methods: A total of 50 subjects diagnosed with category II sacroiliac joint instability and lower back pain were randomly assigned to the control or treatment group. The sacrooccipital technique category II blocking procedure (2-min duration) was performed 3 times a week until the category II indicator of joint instability had subsided. The control subjects were subjected to a sham procedure of equal duration and frequency. We assessed abdominal muscle endurance using the partial curl-up test and shoulder pain using a visual analogue scale, before and immediately after the intervention and 2 weeks after the intervention. Results: On two-way analysis of variance with repeated measures on time factor, significant treatment and interaction effects on muscle endurance were found. A significant interaction effect, but not treatment effect, was found for shoulder pain. Post hoc test showed that the shoulder pain was reduced immediately after intervention (treated group) and 2weeks (control and treated group) after the intervention as compared to before the intervention. Conclusions: This study suggests that sacrooccipital category II blocking can be used to alleviate shoulder pain caused by pelvic instability. The mechanisms behind the long-term benefits may include an increase in abdominal muscle endurance.

• Physical Therapy Korea
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• v.24 no.2
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• pp.1-8
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• 2017

Background: Individuals with spinal cord injury (SCI) rely on their upper limbs for body-lifting activity (BLA). While studies have examined the electromyography (EMG) and kinematics of the shoulder joints during BLA, no studies have considered foot position during BLA. Objects: This study compared the effects of different foot positions during BLA on the shoulder muscle activities, peak plantar pressure, knee flexion angle, and rating perceived exertion in individuals with SCI. Methods: The study enrolled 13 mens with motor-complete paraplegic SCI, ASIA (American Spinal Injury Association) A or B. All subjects performed BLA with the feet positioned on the wheelchair footrest and on the floor independently. Surface EMG was used to collect data from the latissimus dorsi, pectoralis major, serratus anterior, and triceps brachii. The peak plantar pressure was measured using pedar-X and the knee flexion angle with Image J. Borg's rating perceived exertion scale was used to measure the physical activity intensity level. The paired t-test was used to compare the shoulder muscle activities, peak plantar pressure, knee flexion angle, and rating perceived exertion between the two feet positions during BLA. Results: The activity of the latissimus dorsi, pectoralis major, serratus anterior, and triceps brachii and rating perceived exertion decreased significantly and the peak plantar pressure and knee flexion angle increased significantly when performing BLA with the feet positioned on the wheelchair footrest compared with on the floor (p<.05). Conclusion: These findings suggest that individuals with SCI may perform BLA with the feet positioned on the wheelchair footrest for weight-relief lifting to decrease the shoulder muscle activities and the rating perceived exertion and to increase the peak plantar pressure and the knee flexion angle.