• The Korean Journal of Pain
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• v.34 no.4
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• pp.454-462
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• 2021

Background: This study was performed to reveal the relationships between the cross-sectional areas (CSAs) of the paraspinal muscles and the severity of low back pain (LBP), including the level of disability. Methods: This single-center cross-sectional study was conducted on 164 patients with chronic LBP. The effects of demographic characteristics, posture, level of physical activity, disc herniation type, and sarcopenia risk on the CSAs of paraspinal muscles were evaluated along with the relationship between the CSAs and severity of pain and disability in all patients. The CSAs of paraspinal muscles were evaluated using the software program Image J 1.53. Results: A negative significant correlation was found between age and the paraspinal muscle's CSA (P < 0.05), whereas a positive correlation was present between the level of physical activity and the CSA of the paraspinal muscle at the L2-3 and L3-4 levels. The CSAs of paraspinal muscles in patients with sarcopenia risk was significantly lower than those in patients without sarcopenia risk (P < 0.05). The CSAs of paraspinal muscles at the L2-3 and L3-4 levels in obese patients were significantly higher than those in overweight patients (P = 0.028, P = 0.026, respectively). There was no relationship between the CSAs of paraspinal muscles and pain intensity or disability. Conclusions: Although this study did not find a relationship between paraspinal CSAs and pain or disability, treatment regimens for preventing paraspinal muscles from atrophy may aid pain physicians in relieving pain, restoring function, and preventing recurrence in patients with chronic LBP.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.7 no.5
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• pp.1044-1051
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• 2003

This paper surveys the EBP(Error Back Propagation) learning, the Cross Entropy function and the LBL(Layer By Layer) learning, which are used for learning the MLP(Multi Layer Perceptrons). We compare the merits and demerits of each learning method in the handwritten digit recognition. Although the speed of EBP learning is slower than other learning methods in the initial learning process, its generalization capability is better. Also, the speed of Cross Entropy function that makes up for the weak points of EBP learning is faster than that of EBP learning. But its generalization capability is worse because the error signal of the output layer trains the target vector linearly. The speed of LBL learning is the fastest speed among the other learning methods in the initial learning process. However, it can't train for more after a certain time, it has the lowest generalization capability. Therefore, this paper proposes the standard of selecting the learning method when we apply the MLP.

• The Research Journal of the Costume Culture
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• v.23 no.2
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• pp.242-253
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• 2015

The aim of this study was to use a 3D human body scanner to analyze the cross section of different body parts when a girdle is worn. Two types of girdles were selected as experimental garments: a standard type girdle (Garment A) and a high-waist type girdle (Garment B). Their sizes were 88 (S) and 94 (M). Ten female subjects in their twenties who wear girdles sizes 88 (S) and 94 (M) participated the experiment. Their bodies were scanned three times with the 3D human body scanner, before and after wearing experimental girdles. The data were collected by overlapping the cross sections of the 3D scanned body shape data. The space length was measured from the overlapped cross sections. The results show that human body silhouette are changed after wearing the compression type garments and the amount and place of the body change is different by style of garments. First, the waist girth shape became rounder. Second, there was a definite difference in space amount at abdomen girth between two types of girdle. The abdomen area was pushed toward the front after wearing the standard type girdle (A). The high-waist type girdle (B) pushed abdomen area toward the back. Third, there was clear difference at the hip area after wearing two types of girdle. The hip area pushed toward the front with the standard type girdle (A) and pushed toward the back with the high-waist type girdle (B).

• Journal of Advanced Navigation Technology
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• v.22 no.2
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• pp.123-132
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• 2018

In this paper, we design and fabricate a dual liner polarization sinuous antenna with improved cross polarization isolation (XPI). The proposed antenna is composed of four arm radiators for generating dual linear polarization and excited by wideband microstrip balun with Klopfenstein taper structure. Also, two-step cylindrical cavity structure is applied to reduce back radiation. Honeycomb-typed absorbing material is inserted into the cavity to reduce performance degradation by reflected wave. To enhance cross polarization isolation in low frequency band, resistors are adapted between outer arm and the rim of cavity. We confirmed that the fabricated antenna can be applied for polarization measurement due to improved XPI in the low band.

• Steel and Composite Structures
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• v.31 no.6
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• pp.601-615
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• 2019

In cold-formed steel (CFS) structures, such as trusses, wall frames and columns, the use of back-to-back built-up CFS angle sections are becoming increasingly popular. In such an arrangement, intermediate fasteners are required at discrete points along the length, preventing the angle-sections from buckling independently. Limited research is available in the literature on the axial strength of back-to-back built-up CFS angle sections. The issue is addressed herein. This paper presents the results of 16 experimental tests, conducted on back-to-back built-up CFS screw fastened angle sections under axial compression. A nonlinear finite element model is then described, which includes material non-linearity, geometric imperfections and explicit modelling of the intermediate fasteners. The finite element model was validated against the experimental test results. The validated finite element model was then used for the purpose of a parametric study comprising 66 models. The effect of fastener spacing on axial strength was investigated. Four different cross-sections and two different thicknesses were analyzed in the parametric study, varying the slenderness ratio of the built-up columns from 20 to 120. Axial strengths obtained from the experimental tests and finite element analysis were used to assess the performance of the current design guidelines as per the Direct Strength Method (DSM); obtained comparison showed that the DSM is over-conservative by 13% on average. This paper has therefore proposed improved design rules for the DSM and verified their accuracy against the finite element and test results of back-to-back built-up CFS angle sections under axial compression.

• The Korean Journal of Rehabilitation Nursing
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• v.18 no.1
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• pp.38-45
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• 2015

Purpose: This study was attempted in order to verify the effects of moxibustion on aged back pain and activities of daily living. Methods: A research design is quasi-experiment with pre-post test design in nonequivalent control group. As for data collection and experimental treatment, it accidentally sampled totally 50 people with 24 people for the experimental group and 26 people for the control group who appeal for chronic back pain aged over 60 who visited 4 senior centers where are located in N city from November 7, 2012 to December 3, 2012. Experimental treatment was carried out moxibustion totally 12 times by 3 times for 4 weeks in the experimental group. Data analysis was made by using SPSS program. As an analytical technique, the experimental group and the control group were analyzed the homogeneity verification with t-test, Fisher's exact test and $x^2$ test and the hypothesis verification with t-test. Results: The back pain level was reduced in the experimental group than the control group. The disability of daily living activities was reduced in the experimental group than in the control group. Conclusion: Moxibustion was considered to be likely useful therapeutic method for effects of chronic back pain and disability of daily living activities in aged.

• Safety and Health at Work
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• v.5 no.1
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• pp.13-16
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• 2014

Background: This study assesses influences of baseline psychological risk factors on prevalence of low back pain (LBP) at baseline and follow-up among nurses. Methods: A prospective longitudinal study was performed at two phases, baseline and 1-year follow-up among 246 nurses of university hospitals in Shahroud, Iran. A standardized Cultural and Psychosocial Influences on Disability questionnaire was used for data collection. Logistic regression was performed for analysis. Results: At the baseline of the study, 58.9% of nurses reported back pain in the previous 12 months. Age (p = 0.001), belief that work causes pain (p = 0.022), and somatization tendency (p = 0.002) significantly increased risk of LBP. At 1-year follow-up, prevalence of LBP was 45.7% and expectation of back pain at baseline (p = 0.016) significantly increased risk of LBP in this phase (p < 0.05). Conclusion: Results indicate that risk factors for prevalence of back pain at baseline and 1-year follow-up are different. At baseline, the risk factors are age, belief that work causes pain, and somatization tendency, and at follow-up, expectation of pain is the major risk factor.

• Physical Therapy Korea
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• v.16 no.3
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• pp.60-68
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• 2009

Psychsocial factors appear to play an important role in the maintenance and development of chronic disability from low back pain. Fear of pain may be more disabling than the pain itself in patients with nonacute low back pain. The purpose of this study was to identify the contribution of gender, age, depression and pain-related fear to pain intensity and disability in nonacute low back pain patients. This was a cross-sectional survey study of eighty four patients who had low back pain for at least 4 weeks. More than moderate correlations were found between pain intensity, disability, fear-avoidance beliefs and depression. Regression analyses revealed that disability ratings and fear-avoidance beliefs for work activities significantly contributed to the prediction of pain intensity, even when controlling for age, gender and pain duration. Also, fear-avoidance beliefs for physical activity, pain intensity, age and depression, significantly contributed to the prediction of disability, even when controlling for gender and pain duration. These findings suggest that disability scores and fear-avoidance beliefs for work activities are important determinants of pain intensity. They also suggest that fear-avoidance beliefs for physical activity, pain intensity, age and depression are important determinants of disability.

• Journal of the Korean Society of Physical Medicine
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• v.16 no.4
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• pp.1-11
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• 2021

PURPOSE: Lumbosacral orthosis (LSO) is often used to help manage low back pain because it is economical and effective. This study examined the effects of flexible and semirigid LSOs on the lower-limb joint angles in walking in patients with chronic low back pain. METHODS: The effects of the lumbosacral orthosis during gait on the sagittal, frontal, horizontal planes and the change in lower limb angle were examined in fourteen chronic low back pain patients who walked without wearing a LSO, wearing a flexible LSO, and wearing a semirigid LSO in random order for three-dimensional motion analysis. RESULTS: The flexion of the hip and knee joints decreased more significantly during walking with an LSO than without one. The genu valgum angles were reduced in the stance phase more during walking with an LSO than without one. The external rotation of the knee joints in the stance phase increased more during walking with an LSO than without one. CONCLUSION: The angles of the lower-limb joints of patients with chronic low back pain are affected by walking with an LSO, and the effects increased as the LSO stiffened.

• Journal of Convergence for Information Technology
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• v.11 no.10
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• pp.223-229
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• 2021

This study analyzed the effects of an exercise program that combined lumbar stabilization exercise and muscle strengthening exercise and an exercise program that applied only lumbar muscle strengthening exercise on multifidus muscle cross-sectional area, static posture control ability, and low back pain in patients with CLBP. For the study method, 28 patients with CLBP were divided into two exercise propram groups and exercised three times a week for 8-weeks. The data analysis of this study used the t-test to compare before and after group exercise program application, and between each group (p<.05). As a result of the study, significant results were found before and after application of the exercise program within each group, such as multifidus muscle cross-sectional area, static posture control ability, and low back pain (p<.05). Between each group, the exercise program that combined lumbar stabilization exercise and muscle strengthening exercise was found to be more effective (p<.05). In conclusion, it was found that the exercise program with additional lumbar stabilization exercise improved the structure and function of various lumbar vertebrae and reduced lumbar pain.