• 한국기계가공학회지
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• 제11권6호
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• pp.16-21
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• 2012

Magnesium alloy has been focussed as lightweight material owing to its high strength even though low density with aluminum alloy, titanium alloy and plastic material. Friction stir welding technique was performed by rotating and plunging a shouldered tool with a small diameter pin into the joint line between two butted plates and useful to join magnesium alloy. In this paper, the experiments of friction stir welding were done to investigate the joint characteristics of AZ31 magnesium alloy. For its evaluation, the orthogonal array method$(L_{27}(3^{13}))$ was applied with four factors of pin diameter, shoulder diameter, travel speed and rotation speed of tool and also three levels of each factor. Nine tools were worked through shoulder diameter of 9, 12, 15mm and pin root diameter of 3, 4, 5mm. In addition tensile tests were excuted for the assessment of mechanical properties for joint conditions. From the results, pin diameter, shoulder diameter, and rotating speed of tool influenced on the tensile strength meaningful, but welding speed did not influence on that by the variance analysis. Beside of that, optimum condition of tensile strength was estimated as following ; shoulder diameter:15mm, welding speed:200mm/min, rotating speed:200rpm.

• Journal of Acupuncture Research
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• 제23권5호
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• pp.155-165
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• 2006

Objectives : This study was to examine the effect of Intradermal Acupuncture therapy at Kyeonjeong, Cheonryo and Kokji on the shoulder pain. The research was conducted with non equivalent control group non-synchronized design. Methods :　IThe subjects were the women who was suffering for shoulder pain, who are employed at two hospitals in Busan, from April to June, 2006. The 24 women were experimental group who were applied to Intradermal Acupuncture Therapy at Kyeonjeong, Cheonryo and Kokji, while the 20 women were control group who weren't applied to any treatments. The severity of shoulder pain and the extent of the subjective symptoms of shoulder pain were pre-measured. The Intradermal Acupuncture therapy was done a total of 4 times, 2 times a week over 2 weeks and from 11 a.ｍ. to 2 p.m. as an experimental treatment. As a post survey, the severity of shoulder pain, the frequency of shoulder pain and the extent of the subjective symptoms of shoulder pain were measured after one week and two weeks of experimental treatment. Research tools are Visual Analogue Scale by Cline et al. for measuring the severity of shoulder pain and the tool developed by Japan's industrial fatigue research committee of the industrial hygienics society and modified. Results : There was a significant difference(F=4.132, p=0.019) for the severity of shoulder pain on the interaction between time and group. There was a significant difference(F=11.193, p=0.000) for the extent of the subjective symptoms of shoulder pain on the interaction between time and. group. Conclusion : Based on the above results, it can be determined that Intradermal Acupuncture Therapy at Kyeonjeong, Cheonryo and Kokji can be used as the effective treatments for reducing of shoulder pam.

• 대한물리치료과학회지
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• 제29권4호
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• pp.1-16
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• 2022

Background: This study was conducted to examine the correlation of VDT, posture and shoulder function among each group divided by according to the neck pain disorder index (NDI) scores for female patients with neck pain. Design: Cross-sectional study. Methods: Fifty adult women with neck pain voluntarily participated in this study and the neck pain disorder index questionnaire, VDT syndrome assessment tool questionnaire, craniovertebral angle, thoracic kyphosis angle, round shoulder posture, pectoralis minor length, shoulder joint hypermobility, and serratus anterior strength tests were conducted respectively. Subjects were divided into two groups where 21 subjects were allocated to the mild pain group whom have rated below 14 points on the NDI scores, and 29 subjects were in the severe pain group, whom have rated above 15 on the NDI score. Results: The study found that in the mean difference between variables in each group, VDT syndrome showed a higher mean score in the severe pain group than the mild pain group (p<0.05). In the group correlation and regression analysis, the mild pain group showed a significant negative correlation between the craniovertebral angle and round shoulder posture (r=-0.467, p<0.05), and the round shoulder posture for craniovertebral angle was shown to have significant positive influence (B=10.162, p<0.05). The severe pain group showed that the NDI and the VDT syndrome had a significant amount of correlation (r=0.520, p<0.01), the VDT syndrome showed significant positive influence (B=0.330, p<0.05), and the craniovertebral angle showed significant negative influence (B=-0.809, p<0.05). It was also shown that shoulder joint hypermobility had a significant negative correlation with the serratus anterior strength (r=-0.437, p<0.01), and that serratus anterior strength had a significant negative influence on shoulder joint hypermobility (B=-4.175, p<0.05). Conclusion: This study is of clinical significance in that it presented variables that should be considered depending on the degree of neck pain in treating patients with neck pain and that it presented patients with not only posture but also the function of the shoulder joint as factors to consider.

• 동력기계공학회지
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• 제20권3호
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• pp.51-56
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• 2016

In this study, the tensile tests and hardness tests were carried out for the joints characteristics in friction stir welds of Al 5052 alloy. Three way factorial design was applied to optimal welding conditions, whose control factors were shoulder diameter, rotation speed and welding speed of tool. From the results of this study, the optimum condition for maximum yield strength was predicted as the shoulder diameter of 15 mm, welding speed of 500mm/min and rotating speed of 1000 rpm. And the presumed optimal yield strength was estimated to be $167.36{\pm}7.82MPa$ with 99% reliability. In addition the increaser rotation speed of tool and the decreaser welding speed, the decreaser the hardness at welding part.

• Journal of Welding and Joining
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• 제20권4호
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• pp.534-537
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• 2002

In the various industry such as shipbuilding and automobile, etc., Al-alloys are used to reduce weight and improve economical efficiency, and they are mainly utilized in the process of Friction Stir Welding (FSW). A number of studies have been carried out on the metallurgical characteristics of friction stir welding In Al-alloys. However, research on the thermal behavior of FSW by using numerical analysis is not sufficient in the domestic and abroad. In this paper, therefore, numerical simulation was used to find out thermal behaviour of FSW by finite element method. We considered heat source that occurred by friction between tool shoulder including pin and base metal. To confirm the result of simulation, macrostructure is examined and compared after welding. The result of numerical simulation shows that Al-alloy is welded under a melting point of Al around pin by FSW.

• 대한약침학회지
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• 제23권2호
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• pp.44-53
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• 2020

Objectives: Our review aimed to summarize and evaluate evidence on the effectiveness of bee venom acupuncture (BVA) in the treatment of shoulder pain. Methods: Randomized controlled trials (RCTs) evaluating the effectiveness of BVA on shoulder pain were searched up to October 2019 in 11 electronic databases (Medline, Embase, CENTRAL, CiNii, CNKI, VIP, Wanfang, Kmbase, NDSL, RISS, OASIS). The methodological quality of the included RCTs were evaluated using Cochrane Risk of Bias tool and a meta-analysis was performed. Results: Seven studies were included in the review, and four studies were included in the meta-analysis. Comparing BVA plus conventional therapy (CT) with saline injection plus CT, it showed an effect in favor of BVA plus CT in visual analog scale (VAS) and pain rating scale (PRS) (p = 0.02, p = 0.009, respectively). Comparing BVA plus physiotherapy (PT) with saline injection plus PT, it showed that there was no significant difference in VAS and verbal rating scale (VRS) between the two groups. Conclusion: This systematic review and meta-analysis suggest that BVA could be beneficial as an adjuvant treatment for shoulder pain.

• 한국산업보건학회지
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• 제19권2호
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• pp.156-169
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• 2009

In this study, the authors introduced DASH (Disabilities of the arm, shoulder, and hand), which had been developed for evaluating the functional impairment in the movement of upper extremities in regular daily activities, work ability and sports/performing arts ability. It is an ergonomic risk assessment tool used for industrial workers and also a disability measurement tool for upper extremity disorders arising from musculoskeletal disorders and symptom. This study intended to examine the applicability of DASH in occupational health field. Firstly, DASH development process and composition were reviewed through The DASH outcome measure user's manual and early articles. Secondly, reliability, validity, and responsiveness of the DASH in various languages at the application stage as well as its reliability and validity at the early stage of development were investigated. Thirdly, focusing on the application of DASH to clinical cases, workers with musculoskeletal symptoms, healthy workers, workers with other diseases, and general population were discussed besides workers with major musculoskeletal disorders. Lastly, DASH questionnaire was examined for its potential as a reference for assessing the functional impairment in the movement of upper extremities of workers with musculoskeletal symptoms in industrial workers in Korea.

• 대한정형도수물리치료학회지
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• 제17권1호
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• pp.35-44
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• 2011

Background: This study was to suggest the process of making strategy for effective intervention and evaluation on functional problems of the frozen shoulder patient applied International Classification of Functioning Disability and Health (ICF) Tools. Methods: The patient was 48years old woman with right shoulder adhesive capsulitis and calcific tendinitis. In first phase, therapists could list the information relating to functional problems used by the ICF Core set and then could confirm the interaction among the problems using the ICF assessment sheet. In second phase, therapist is needed to make the hypothesis and hypothesis testing and then set a primary functional goals and therapeutic goals in detail after prioritizing the problems to be managed based on the problem list. Lastly, after setting the confirmed problems as the purpose of intervention through the hypothesis testing, therapist could do some intervention after making a plan to solve these problems. Results: This report illustrates how to apply the process based on ICF concept into physical therapy practice. The decided hypothesis and goal that are to solve the problems the client faced were remarkably meaningful. Conclusions: Clinical decision making for the most effective intervention requires that therapists use the clinical reasoning process based on ICF concept.

• Clinics in Shoulder and Elbow
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• 제18권2호
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• pp.86-90
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• 2015

Background: Although there are several methods for evaluating bone quality, Hounsfield units (HU), a standardized computed tomography (CT) attenuation coefficient, provide a useful tool for estimating focal bone mineral density (BMD). The aim of this study is to investigate the HU for evaluating the degree of osteoporosis in greater tuberosity with regard to anchor positioning. Methods: Forty patients diagnosed as normal on shoulder CT were included and categorized according to age and gender. Axially sectioned CT images were processed to 3-dimensional models containing information about bone quality using Mimics (14.11 platform v14.1.1.1 Materialise). Three-dimensional anchors were simulated and positioned according to 6 regions of interest (ROI) in the greater tuberosity classified using Tingart's system. Mean HU of intra-anchor volumes in the 6 regions was measured. Results: A significant decrease in HU was observed with increasing age (p=0.0001) and menopause (p<0.001). A significant difference in HU was found between male and female groups with males showing the higher values (p=0.0001). HU of proximal areas of ROI was higher than those of distal areas (p<0.005). However, although mean HU of distal posterior ROI showed the lowest values, no statistically significant difference was found between anterior, middle, and posterior regions (p=0.087). Conclusions: Mean HU of ROIs provides a tool for preoperative assessment of focal BMD, which is a factor of suture anchor stability and can be used to aid decision-making regarding secure anchor positioning for rotator cuff repair. Our data support that the most secure point is the proximal regions of ROI.

• 한국안전학회지
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• 제17권4호
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• pp.178-183
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• 2002

The purpose of this study was to quantitatively investigate the effects of external load upper extremity posture on perceived discomfort. An experiment was conducted for measuring discomfort scores depending upon external loads and upper extremity postures, in which the free modules and numeric estimate method of the magnitude estimation was adopted as a tool for obtaining discomfort ratings. The upper extremity postures were controlled by wrist flexion/extension, elbow foexion, shoulder flexion, and shoulder adduction/abduction. The results showed that all experimental variables except shoulder adduction/abduction were significant at ${\alpha}$=0.01 or 0.05. The effect of external load was very much larger than that of upper extremity postures. Therefore, it is recommended that a new posture classification scheme taking effect of external load to into consideration be developed for quantifying postural load.