• Proceedings of the Membrane Society of Korea Conference
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• 2005.11a
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• pp.215-218
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• 2005

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.152-153
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• 2007

industrial site has led to a growing concern for harmonic distortion and the resulting impacts on system equipment and operation. Harmonic current is generated by the operation of non-linear load, it means that voltage and current waveforms exhibit a non-linear relationship. Harmonics cause increase losses in the customer and utility power system components. This paper describes application of instantaneous active and reactive theory for the compensation of harmonic currents in three-phase non-linear load.

• Bulletin of the Korean Chemical Society
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• v.4 no.1
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• pp.45-47
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• 1983

In order to standardize the ${\sigma}^*,\;{\rho}^*$ is taken as unity for the benzoic acids by analogy with the fact that ${\rho}$ of benzoic acids in the ground state is taken as unity. The $pK_{\alpha}^*$ of many benzoic acid derivatives are determined by UV spectroscopy and fluorescence spectral analysis whenever possible. The ${\sigma}^*$ constants are derived from the Hammett equation utilizing these $pK_{\alpha}^*$ values and the $pK_{\alpha}^*$ of the benozic acid derivatives showed better correlationship with ${\sigma}^*$ than ${\sigma},\;{\sigma}^+\;and\;{\sigma}^-$ as expected. From these ${\sigma}^*$ values, ${\rho}^*$ of the phenol derivatives was calculated to be 1.28. The new standardized ${\sigma}^*$ values are calculated from the $pK_{\alpha}^*$ values of phenols since more accurate and abundant data are available for phenols than the benzoic acid derivatives.

• Journal of the Chungcheong Mathematical Society
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• v.4 no.1
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• pp.71-74
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• 1991

In this paper, we study the Bourgain property for real-valued functions, and give conditions for a family of real-valued functions to have the Bourgain property.

• Journal of the Korean housing association
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• v.10 no.3
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• pp.181-186
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• 1999

• Journal of Korean society of Dental Hygiene
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• v.18 no.1
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• pp.65-75
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• 2018

Objectives: This study aims to contribute to the prevention of dental diseases and health care in the elderly by investigating the relationship among the experiences of chronic diseases, dental health status, and the behaviors in the Korean elderly people. Methods: A total of 2,856 elderly people aged 65 or older were selected as the final analysis subjects using data from the 6th National Health and Nutrition Examination Survey (2013-2014). Chronic diseases were defined as 'cardiocerebrovascular diseases', 'diabetes', 'chronic respiratory diseases', and 'cancer' diagnosed by the doctors. For the statistical analysis, SPSS 21.0 for Windows was used. Descriptive analysis and a Chi-square test were conducted to investigate the relationship among the experiences of chronic diseases, general characteristics, dental health status, and the behaviors in the Korean elderly. Finally, logistic regression analysis was performed to investigate the relationship among the experiences of chronic diseases, dental health status, and the behaviors. Results:The prevalence of Cardiocerebrovascular diseases was significantly higher in the 3-4 group of community periodontal index with the score of 1.36 (95% CI 1.03-1.00) than in the 0-2 group. The prevalence of Cardiocerebrovascular diseases was significantly higher in the group without dental examination during the past one year with the score of 1.29 (95% CI 1.00-1.66). The prevalence of diabetes was significantly higher in the uncomfortable speaking state group with the score 1.46 (95% CI 1.12-1.91). The prevalence of cancer was significantly higher in the partial denture needs group with the score 1.67 (95% CI 0.98-2.83). Conclusions: Regular dental examinations and dental health care for the elderly with chronic diseases showed that periodontal health and residual teeth could be maintained and managed. Therefore, continuous customized dental health services should be implemented for the elderly with chronic diseases.

• The Journal of Korean Physical Therapy
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• v.28 no.5
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• pp.297-302
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• 2016

Purpose: This study was conducted to evaluate the effects of bridge exercise on the structural characteristics of trunk muscles in patients with lumbar pain by applying the exercise on either a stable or an unstable surface. Methods: Thirty subjects participated in the experiment and were randomly divided into an unstable bridge exercise group (UBEG) and a stable bridge exercise group (SBEG). The exercise program for each group was conducted three times a week over a six-week period. The structural characteristics of trunk muscles were measured by obtaining images using an ultrasound imaging device. Results: The thicknesses of the external oblique (EO), internal oblique (IO), and transverse abdominis (TrA) and the fiber angle of the erector spinae (ES) in the UBEG and the SBEG showed statistically significant increases in all items measured after the experiment. A comparison of groups conducted after the experiment to determine the effects of the exercise on each group showed no significant differences between groups for any of the measured items. Conclusion: A comprehensive review of the study results showed statistically significant increases in the thicknesses of the EO, IO, and TrA and the fiber angle of ES in both the UBEG and the SBEG. While the comparison of the groups with respect to the effects of the exercise revealed no significant differences, there were relatively larger effects in the UBEG than in the SBEG.

• Journal of the Korean Society of Clothing and Textiles
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• v.38 no.4
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• pp.440-454
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• 2014

This study examined the wearing effect of 3D compression suits on quantitative electroencephalogram (EEG) during walking and rest. Ten males in their 20s wore three types of experimental clothing, a loose-fit wear (BS), a 3D compression suit (3D CS), and a power film welded on CS (3D WCS); in addition, EEG signals were measured during resting, walking, after walking, and after sit-ups. The results showed that a higher pressure (due to 3D CS and 3D WCS) increased the 'Concentration' level and the 'Cognitive load' of brain waves during treadmill walking due to a higher cortex activity level when walking. Differentiation was shown between two compression suits and BS was enhanced during walking on a treadmill; however, the brain waves of 'Relaxation' between two compression suits were significantly different after walking, i.e., 'Relaxation' level of 3D WCS was the highest. Rigorous exercise such as sit-ups was inefficient to distinguish the effect of compression suits on EEG. Participants perceived a higher pressure due to compression suits; however, the wear comfort of two compression suits was maintained. Two compression suits were rated as supportive and helpful during walking. Various EEG parameters such as the indices of 'Relaxation', 'Concentration' and 'Cognitive load' were effective to observe the effect of 3D compression suits on wearers' brain waves during and after walking.

• Journal of the Korean Society of Radiology
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• v.6 no.1
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• pp.27-37
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• 2012

From Jan 2002 to June 2011, we evaluated 4419 cases of radiation dose of 323 radiation related individuals consist of physician, nurses, technician and others in local C national university hospital. On annual analysis, year 2003 ranked the highest and 2007 the lowest dose. Dose was relatively higher in male than female. Dose was highest in 30s on age basis analysis. Dose was high in order of physician, nurse, and technician. Average radiation dose was high in order of cardiovascular center, radiologic intervention ceter, radiologist individuals, and fluoroscopic contrast study room. Those doses did not excess the standard dose recommended by ICRP (20mSv/year). However unlike average dose, there are wide variations of dose in individuals. Therefore radiation related workers should do one's best in personal radiation exposure dose management for achievement of minimum dose of radiation.

• Proceedings of the KSCN Conference
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• 2005.10a
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• pp.73-73
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• 2005