• Journal of Oral Medicine and Pain
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• v.10 no.1
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• pp.113-124
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• 1985

In order to observe the effect of mandibular orthopedic repositioning appliance (MORA) on body strength, the author measured back muscle strength with Digital Back Muscle DYNAMOMETER (TAKEI KIKI KOGYO Co., Tokyo, Japan) before MORA, 15 days after and 30 days after MORA in 12 men and then analysed them statistically. The subjects were weight-lifting athletes of Seoul Athletic High School without dysfunction of masticatory system. MORA was fabricated at 1.0-1.5rnm isotonically closed position (Myocentric Occlusion Position) from mandibular rest position (Myocentric Rest Position) using Myo-monitor (MyoTronics Research Inc., Seattle, Washington, USA) and-SVT C-II (Tokyo Shizaisha Inc., Tokyo, Japan). The results were as follows : 1. The mean of back muscle strength before MORA was 150 kg, that of 15 days after MORA was 165 kg (4.43% increase than before), and that of 30 days was 175 kg (10.76% increase than before). 2. There was a significant difference among back muscle strength before MORA, 15 days after and 30 days after MORA (P<0.01: repeated measures one-way ANOVA). 3. According to the result of determining mandibular position for MORA fabrication, mandibular rest position after relaxation with Myo-monitor was 3.2mm lower, 1.0mm posterior, and 0.5 mm left from centric occlusion. And the mean of the amount of lateral deviation was 0.7 mm.

• Journal of the Ergonomics Society of Korea
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• v.16 no.3
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• pp.49-60
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• 1997

Although the tasks are being mechanized or automated today, many tasks are still performed manually in several industrial settings. Manual materials handling and improper sorking postures are known to be a major cause of low back injuries, which are one of the major problems in the economic and public health aspects. In this study, two machine repair shops of a manufacturing company in Pohang were recommended by the company health care center to investigate the potential risk factors that may cause low back injuries. Five machine repair tasks were selected from each machine repair shop, which are accountable for relatively high complaints of low back pain. The purpose of this study is to quantitatively evaluate the hazards of the tasks, and finally to recommend the improved methods and guidelines for safe work practices. In order to accomplish this goal, the questionnaire study and ergonomic evaluations were carried out and the results were analyzed. For most of the tasks under study, workers were found to be exposed to relatively high biomechanical stresses in low back, mainly due to the heaby objects handled and the improper working postures.

• The Journal of the Korea institute of electronic communication sciences
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• v.8 no.6
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• pp.881-889
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• 2013

In this paper, a nonlinear and adaptive back-stepping control technique is proposed for a speed control of IPMSM(Interior Permanent Magnet Synchronous Motor). The gain of back-stepping controller(including integral value of the states error) is designed for stability of the system. In order to adapting fast in variation of load torque, the controller is including load torque estimator. The simulation is completed by using PSIM software. The simulation results show that the designed back-stepping controller make the system stable in the constant torque region, and has better tracking performance than a controller without the integral gain.

• Journal of Korean Physical Therapy Science
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• v.7 no.2
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• pp.415-425
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• 2000

It is well known that the lifetime incidence of low back pain is extraordinarily high, but those who incur the majority of the cost, both personally and financially, are the chronic pain. Stabilization programmers attracted our interest, with their aims of using the muscle system to protect spinal joint structures from further repetitive microtrauma, recurrent pain and degerative change. In overviewing the stabilizing role of the trunk and back mucles our attention became focused on muscles which controlled the lumbar and lumbosacral joints rather than on muscles which span the spine from the thorax to pelvis. It was considered that muscles such as the lumbar multifidus, transversus abdominis, and possibly also parts of the obliquus internus abdominis, would most likely function to stabilize the segments of the lumbar spine. In order to check if these muscles were functioning in low back pain patients, it was necessary to devise specific muscle tests. The new concept involves exercises using only relatively low activity levels in the muscles. More emphasis is placed on a motor skill which has to be relearned, practised and then gradully incorporated back into functional movement.

• Fashion & Textile Research Journal
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• v.18 no.1
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• pp.91-102
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• 2016

This study classified the lower body types of female adults aged 18 to 69. The lower body was divided into front, lateral front, and lateral back. In order to understand the shape and somatotype of each segment, 592 people were analyzed based on girth, height, length, depth, width, angle and cross section distance for each segment. For data analysis, SPSS 18.0 was performed for descriptive statics, principal component analysis, K-means cluster analysis, ANOVA, and Duncan's test (as verification). Factor analysis was performed based on index values, calculation values, angles, and cross section distances. The measured items resulted in a.) 16 items were extracted to 5 factors in the case of the front factor (FF) of the lower body, and b.) 24 items were extracted to 6 factors in the case of lateral front factor (LFF) and lateral back factor (LBF). Each factor was put through K-means cluster analysis, classifying the lower bodies into one of four types of based on the front type (FT), the lateral front type (LFT), and the lateral back type (LBT) respectively. This study proposed an understanding of various lower body shapes by segmenting and classifying the lower body shapes for each type.

• Transactions of Materials Processing
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• v.12 no.8
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• pp.724-729
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• 2003

In order to study the shearing characteristic of anti-vibration sheet metal which is used to reduce vibration noise, a blanking die was manufactured to blank a workpiece. The variables employed in this study were clearance, type of stripper plate, position of the rubber layer and type of the die design. These variables were used to study the effects on burr height, blank diameter and camber height. In the case of burr height from experimental investigation, the push-back die, combined with a movable stripper plate, showed greater burr height. The rubber-top position of a workpiece resulted in better qualities regardless of working variables. In the comparison of diameter measurement, the use of the push-back die with a fixed stripper plate, with a 4.5% clearance, showed better accuracy. For comparing camber height, the push-back die resulted in less cambering than the drop-through die. Also, the larger the clearance, the greater was the camber height. Considering experimental results, the shearing of anti-vibrational sheet metal is best achieved when the rubber layer is laying on the top, blanked with a fixed stripper plate in a push-back die, with a 4.5％ clearance.

• Journal of Acupuncture Research
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• v.19 no.2
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• pp.137-148
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• 2002

Objective : The low back pain was the main reason of receiving acupuncture treatment. Despite its widespread prevalence, objective data assessing the pain and the results of various forms of treatment were difficult to find in korea. In order to compare the value of different types of treatment, it was necessary to use standard and meaningful forms of assessment. Methods : Pain and functional disability scales for low back pain were reviewed for contents, measurement properties and current methodological issues. Results and Conclusions : 1. The SF-36 Bodily Pain Scale and the Graded Chronic Pain Scale were commonly used for the standard pain scale. 2. The Oswestry Disability Questionnaire and the Roland-Morris Disability Questionnaire were commonly used for the standard function scale. 3. When evaluated, there was no definite answer to the results of the treatment. In the literature, the responsiveness of the Roland-Morris Disability Questionnaire ranged from 2 to 8 points but clinically, the ranges should be minimally changed from 2 to 3 points. 4. In the future, scale for low back pain should be standardized in multiple dimension so that the computerized adaptive testing by Item Response Theory could be widely used.

• Proceedings of the KWS Conference
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• 2007.11a
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• pp.17-19
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• 2007

The fatigue experiments of friction stir welded Al-6061-T6 alloy with and with out back bead were performed to investigate the variation in fatigue strength and life of the Joint. It was found that there were always existed flaws at the roots of friction stir welds for the normal welding parameters and clamping conditions. In order to overcome this root flaws, friction stir welds with optimum back bead has been developed. The test results with root flaws and with back bead were compared. The fatigue life of weld with root flaws was 5-10 times shorter than that of the friction stir weld with back bead.

• Korean Journal of Community Nutrition
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• v.8 no.5
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• pp.755-762
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• 2003

The purpose of this research which, surveyed target hospitals, was to evaluate job operations by surveying the influences of Quality Improvement (QI) activities in various divisions related to a decrease in their back-up orders. Statistical data analyses were completed using the SPSS 11.0 program. The results can be summarized as follows Before QI there were 147 cases of back-up orders ; after QI there were 83 cases, decrease of 64 cases. This was 44%, less than the projected goal of 50%. For each item, there was a decrease of 40 nurse cases, 9 patients and patron cases,9 test surgery deliverly cases and 5 doctor cases after QI. The registering of midnight meals was not shown after QI, due to the Order Communication System (OCS) settlement. After performing QI, the average manual operation per month was reduced from 840 minutes to 498 minutes, of which the difference was 342 minutes, and the average of 342 minutes per month could be used for the peculiar operation of each division. This QI activity provided a good opportunity for establishing cooperation among divisions in providing meals to patients through interactions among divisions. It was recognized that these interactions were effective only when medical services were achieved through organized cooperation among divisions. Among the 7 items included on the patient satisfaction questionnaire, “satisfaction with offered menus” (p<0.01) showed significantly higher scores before QI. However “satisfaction with meal times” (p<0.01) showed significantly lower scores before QI.

• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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• v.15 no.2
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• pp.25-34
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• 2009

Purpose : The purpose of this study is to investigate that the Effects of Pain, Lumbar Flexibility and Abdominal Obesity of Patient with Low Back Pain and Abdominal Obesity after Lumbar Strengthening Exercise. Methods : The selected subjects of this study were 17 patients who had diagnosis on low back pain and body mass index was more than $25kg/m^2$ and lumbar length was more than 90cm. They divided into a control group with 10 patients doing lumbar stabilization exercise and an experimental group with 7 patients ding simple lumbar strengthening exercise in order to compare degrees of oswestry disability index and lumbar stability, lumbar length was measured before the exercise, in 4 weeks and 8 weeks after exercises respectively. Result : lumbar strengthening exercise on patients with low back pain and abdominal obesity affected improving function of lumbar and decrease of pain with abdominal obesity. Conclusion : Then lumbar stabilization exercise than simple strengthening exercise affected decrease of Visceral fat tissue on abdominal obesity.