• Journal of Welding and Joining
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• 제10권3호
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• pp.54-62
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• 1992

Large steel water pipes are joined prevalently by bell and method and welded at inside and outside of lapped parts. According to the Korean Standard(KS) for fabrication of water pipes, the weldments are designed to have the length of leg which is same as or larger than the thickness of the pipe. It is recently pointed out that the standard size of weldments is too large, which results in an excessive consumption of material and labor. In this study, several cases of weldments having different sizes were investigated to reduce the length of leg to the effective size. For each case, the analysis of stresses was carried out to evaluate the safety of the welded pipes by using a package program, ANSYS, under the consideration of the loading condition of water pipes which includes the soil pressure on the pipe, the load over the road, and temperature change of the pipe. The results of this study revealed that the weldment which has the length of leg of the size over 0.7*thickness of the pipe could provide a stress level below the yield strength. Especially when the length of leg is 85% of the wall thickness, the maximum equivalent stress is only slightly higher than that of the leg of fillet of the size of 1.0*pipe thickness.

• 근관절건강학회지
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• 제19권1호
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• pp.27-36
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• 2012

Purpose: The purpose of this study was to investigate the leg length Inequality, habitual posture, and pain in women's college students. Methods: The subjects were 281 students, in 8 women's college in Korea. The tapelines were used for measuring leg length Inequality and questionnaires were used for measuring habitual posture, and pain. The data were collected between August and October 2010 and analyzed using SPSSWIN 11.5. length Inequality(<1 cm). The subjects of 2.8% were the length differences of above 2cm. The worst habitual posture were leaning habits. Especially, the habits of crossing her legs were significantly different to leg length Inequality(F=3.342, $p$=.037). The subjects of 84% were felt a severe pain on the upper body such as waist, back, scapula, neck or shoulder. But there is no difference between pain and leg length Inequality. Habitual posture are related to pain(r=.212, $p$=.001). Conclusion: To protect the severe health problem of musculoskeletal system, this study results will be give aid to health education in women's college students.

• 한국의류산업학회지
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• 제15권2호
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• pp.240-246
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• 2013

Data from 540 subjects (included in the obesity group whose BMI was over 25) was selected from 2,445 subjects in the $6^{th}$ Korean Body Size Survey. A total of 25 direct measurements were selected for the relevant literature lower body size measurement analysis, that included 9 components related to BMI, height and circumferences, 3 components related to width and thickness, 5 components related to length, 3 components related to height, and 2 other components. Descriptive statistics, factor analysis, cluster analysis and variance analysis were executed using PASW 18.0 to analyze the data. In accordance with the factor analysis results to classify the lower body shape of overweight women in their 20s to 60s whose BMI was over 25, 4 factors were identified (lower body volume, leg volume, lower body length and leg length). A total of 4 lower body shapes of overweight women were found through cluster analysis using 4 factor scores from the factor analysis. Body Shape 1 had the largest lower body and leg volume. It was the heaviest group. Leg length was at a normal level. Body Shape 1 was 22.2% (122 subjects). Body Shape 2 had the longest legs and the smallest body shape; however, Body Shape 2 was the leg obesity group with the largest leg volume. It was 39.8% (215 subjects). Body Shape 3 had a smaller leg volume in proportion to the lower body thickness and a long lower body length. It comprised 27.8% (150 subjects). Body Shape 4 comprised 9.8% (53 subjects) with the shortest leg. Its lower body obesity was at a normal level.

• Safety and Health at Work
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• 제12권4호
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• pp.511-516
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• 2021

Background: Difficulties in walking and balance are risk factors for falling. This study aimed to predict dynamic balance based on demographic information and anthropometric dimensions in construction workers. Methods: This descriptive-analytical study was conducted on 114 construction workers in 2020. First, the construction workers were asked to complete the demographic questionnaire determined in order to be included in the study. Then anthropometric dimensions were measured. The dynamic balance of participants was also assessed using the Y Balance test kit. Dynamic balance prediction was performed based on demographic information and anthropometric dimensions using multiple linear regression with SPSS software version 25. Results: The highest average normalized reach distances of YBT were in the anterior direction and were 92.23 ± 12.43% and 92.28 ± 9.26% for right and left foot, respectively. Both maximal and average normalized composite reach in the YBT in each leg were negatively correlated with leg length and navicular drop and positively correlated with the ratio of sitting height to leg length. In addition, multiple linear regressions showed that age, navicular drop, leg length, and foot surface could predict 23% of the variance in YBT average normalized composite reach of the right leg, and age, navicular drop, and leg length could predict 21% of that in the left leg among construction workers. Conclusion: Approximately one-fifth of the variability in the normalized composite reach of dynamic balance reach among construction workers using method YBT can be predicted by variables age, navicular drop, leg length, and foot surface.

• 한국해양공학회지
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• 제13권2호통권32호
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• pp.51-57
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• 1999

In this study, one side fillet welded T-joint, used in box type girder and other welding structure, was investigated by stress analysis and bending fatigue test without edge preparation, with variation of joint shape. The purpose of this study is to give the welding condiltion and design standard on manufacturing one side fillet welded T-joint. As a result, the following conclusions were obtained. 1) In one side fillet welded T-joint, the larger the leg length and the penetration depth, the greater the bending fatigue strength because reduction of stress and strain on toe and root. The increase of the longitudinal leg length rather than vertical leg length contributed to the increase in bending fatigue strength. 2) In one side fillet welded T-joint without edge preparation, both general manual welding and general automatic welding were carried out with same condition. In this case, automatic welding showed deeper penetration and more increased longitudinal leg length than manual welding, so that automatic welding offers greater bending fatigue strength. 3) For one side fillet welded T-joint without edge preparation with automatic welding, the ratio(h/t) of the leg length(h) and the main plate thickness(t) in which toe crake can occur was 1.0 over.

• Journal of Welding and Joining
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• 제21권3호
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• pp.46-50
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• 2003

The horizontal fillet joint is one of the most important weld joints in the shipbuilding industry. High-speed rotating arc welding, which can increase the leg length, is an effective way to improve the weld productivity and quality for the horizontal fillet welding. Based on the Taguchi method, the effects of welding parameters on bead characteristics - leg length, asymmetry, undercut, overlap - are investigated fur high-speed welding process. As a result, the adequate welding parameters are selected for the required leg length, symmetric bead and no undercut. Besides, considerably consistent leg length is observed for the horizontal fillet welding with gap variation up to 3mm.

• 한국운동역학회지
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• 제26권1호
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• pp.101-113
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• 2016

Objective: The purpose of this study was to investigate the effect of leg length discrepancy (LLD) on the human body during gait and standing posture. Methods: The study group comprised of 17 adult participants with LLDs of <1 cm. LLDs were artificially induced to 0, 1, 2, and 3 cm. The proportion of weight distribution, shift of the mean center of pressure, and Cobb's angle were measured in the standing position. Kinematic variables such as walking and striding width and time, and the proportion of stance phase for single- and double-limb gait were measured as well. The participants were required to either stand or walk on a treadmill (Zebris FDM) with a pressure plate, and the Cobb's angle measurements were obtained from radiographs. Results: A discrepancy of 3 cm in leg length resulted in a statistically significant shift of the center of pressure in the standing position. Moreover, the Cobb angle increased as the discrepancy became larger. The step length and width of the longer (left) leg during gait statistically significantly increased when the discrepancy was 2 cm. In addition, step time was statistically significant when the discrepancy between the longer (right) and shorter (left) legs was more than 2 cm. The proportion of single-limb stance phase was statistically significant as the discrepancy became larger, especially when the discrepancy was >2 cm for the longer (right) leg and 1 cm for the shorter (right) leg. Conclusion: The study showed that LLD influenced deformations of the human body and walking.

• 대한추나의학회지
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• 제5권1호
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• pp.213-222
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• 2004

Objectives : To investigate contributing degree of other factors except pelvic tilting to F.L.L.D by analizing with Gonstead technique on the correlation between femur head height discrepancy on the standing pelvic AP view and F.L.L.D caused by pelvic tilting. Method : We analysed standing pelvis AP X-ray of 70 patients who had visited at the department acupunture and moxibustion in Conmaul oriental medical hospital, during May, 1st, 2004 - July, 30th, 2004, with low back pain or lower extremity pain. We excluded the person with any past history of polio, genetic defect, malunited fracture, growth plate injury, infection and overgrowth attributable to hemangioma, or arteriovenous fistula. Results & Conclusion : The functional leg length discrepancy caused by pelvic tilting and femur head height difference had no statistical difference(p=0.132) but poorly correlated(Pearson ${\nu}=0.05$). In the 94.28% of subjects, the femur head height difference wasn't in accord with F.L.L.D. caused by pelvic tilting. In 47.14% of subjects were expected to have over $3^{mm}$ of leg length discrepancy after pelvic adjustment. The mean of measurement difference between two methods was $3.76{\pm}3.12^{mm}$ and the range was $0{\sim}11.4^{mm}$. Consequently, we must consider not only functional leg length discrepancy caused by pelvic tilting but also anatomical leg length discrepancy, misalignment of ankle, knee or hip joint etc.

• 대한추나의학회지
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• 제3권1호
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• pp.55-64
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• 2002

Objectives : Acupuncture therapy is known as a effective method to CVA with paralysis. To make clear about effectiveness of acupuncture affecting to active and static postural adaptation for the patient with hemiparesis, we studied whether acupuncture changed ability of maintenance with one leg standing posture, and character of gait such as gait velocity, cadence, stride length, step length and base of support. Methods : This clinical study has been carried out with 10 cases of CVA patient with hemiparesis. We treated patients with acupuncture for 4 weeks, estimated each paralytic leg and well leg before 1st treatment and after last treatment, and compared the change of one leg with the other. To estimate the change of ability of static postural adaptation, we checked the time of duration with one leg standing posture. And about active postural adaptation, we used temporal distance gait analysis with Ink-Foot-Print method. Results and Conclusions : In static postural adaptation, paralytic leg significantly improved the duration with one leg posture. And In active postural adaptation with gait analysis, paralytic leg showed significant improvement in stride length and step length. Base of support and cadence were also significantly improved.

• PNF and Movement
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• 제16권2호
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• pp.267-273
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• 2018

Purpose: Leg length discrepancy (LLD) is one of the risk factors for postural imbalance. This study aimed to investigate the effect of induced leg length discrepancy on the limitation of stability (LOS) and static postural balance. Methods: Thirteen adults (males, 7; females 6) participated in this study. The LOS and static postural balance [sway length, sway area, and sway velocity of center of gravity (COG) displacement] were measured by the balance trainer system. The subjects were asked to move the COG for the anterior, posterior, and left and right directions maximally and to keep standing on the platform with and without induced LLD for 30 s in the open and closed eyes conditions, respectively. The LLD was artificially induced to 2 cm using insole. Wilcoxon test was used to compare the LOS and the static postural balance between with and without induced LLD. Results: The anterior and posterior LOS significantly decreased in induced LLD (p<0.05), and the left and right LOS were not significantly different between with and without LLD (p>0.05). Sway length, sway area, and sway velocity of the COG displacement significantly decreased in induced LLD (p<0.05). Conclusion: This study suggests that induced LLD could decease the antero-posterior LOS and increased the static postural balance. Therefore, the LLD could disturb the postural balance.