• Journal of the Korean Magnetics Society
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• v.24 no.5
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• pp.146-151
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• 2014

The pulse waveforms of a carotid artery in the neck and a radial artery in the hand wrist were individually measured by using clip-type pulsimeter equipped with a permanent and Hall device. The pulse transit time and the pulse wave velocity obtained through comparison of two pulse waveforms were analyzed each other. A value of the pulse wave velocity was about 8.5 m/s similar to one measured by a conservative method. This result suggests that the clip-type pulsimeter as the reproducible and reliable one oriental diagnostic medical device can be predicted to any atherosclerosis state in the cardiac circulatory system.

• Journal of Adhesion and Interface
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• v.14 no.3
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• pp.135-145
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• 2013

Epoxy resin compositions were studied on the view of self-extinguishing properties without retardant additives and suitability as materials of eco-friendly EMC (Epoxy molding compound). Cured epoxy and phenolic resin composition having conjugated double bond of aromatic structure exhibited self-extinguishing properties and low heat release capacity. In this study, the structure of long conjugated double bond of hetero-atom type azomethyne group between conjugated double bonds of aromatic structure showed lower heat release capacity. Low heat release capacity seemed to be related with high reaction enthalpy, $T_g$ and reactivity affected by hetero-atom structure in azomethyne group.

• Geophysics and Geophysical Exploration
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• v.2 no.3
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• pp.142-148
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• 1999

Three-dimensional electromagnetic modeling algorithm in homogeneous half-space was developed using the extended Born approximation to an electric field integral equation. To examine the performance of the extended Born approximation algorithm, the results were compared with those of the full integral equation results. For a crosshole source-receiver configuration, the agreement between the integral equation and the extended Born approximation was remarkable when the source frequency is lower than 20 kHz and conductivity contrast lower than 1:10. Beyond this conductivity contrast, the simulated results by the extended Born approximation exhibit a difference with respect to those by the integral equation. Therefore, the limit of accuracy lies below contrast of 1:10 in the extended Born approximation. Since for the source frequency range from 20 kHz to 100 kHz, however, the difference is relatively small, the extended Born approximation could be used for a reasonable 3-D EM modeling algorithm.

• Journal of radiological science and technology
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• v.44 no.4
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• pp.327-333
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• 2021

Magnetic resonance imaging(MRI) uses strong magnetic field to image the cross-section of human body and has excellent image quality with no risk of radiation exposure. Because of above-mentioned advantages, MRI has been widely used in clinical fields. However, the noise generated in MRI degrades the quality of medical images and has a negative effect on quick and accurate diagnosis. In particular, examining a object with a detailed structure such as brain, image quality degradation becomes a problem for diagnosis. Therefore, in this study, we acquired T2 weighted 3D data of multiple sclerosis disease using BrainWeb simulation program, and used quantitative evaluation factors to find appropriate slice thickness among 1, 3, 5, and 7 mm. Coefficient of variation and contrast to noise ratio were calculated to evaluate the noise level, and root mean square error and peak signal to noise ratio were used to evaluate the similarity with the reference image. As a result, the noise level decreased as the slice thickness increased, while the similarity decreased after 5 mm. In conclusion, as the slice thickness increases, the noise is reduced and the image quality is improved. However, since the edge signal is lost due to overlapped signal, it is considered that selecting appropriate slice thickness is necessary.

• Journal of radiological science and technology
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• v.26 no.1
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• pp.71-82
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• 2003

In this paper, I proposed a classifier of liver cirrhotic step using T1-weighted MRI(magnetic resonance imaging) and hierarchical neural network. The data sets for classification of each stage, which were normal, 1type, 2type and 3type, were obtained in Pusan National University Hospital from June 2001 to december 2001. And the number of data was 46. We extracted liver region and nodule region from T1-weighted MR liver image. Then objective interpretation classifier of liver cirrhotic steps in T1-weighted MR liver images. Liver cirrhosis classifier implemented using hierarchical neural network which gray-level analysis and texture feature descriptors to distinguish normal liver and 3 types of liver cirrhosis. Then proposed Neural network classifier teamed through error back-propagation algorithm. A classifying result shows that recognition rate of normal is 100%, 1type is 82.3%, 2type is 86.7%, 3type is 83.7%. The recognition ratio very high, when compared between the result of obtained quantified data to that of doctors decision data and neural network classifier value. If enough data is offered and other parameter is considered, this paper according to we expected that neural network as well as human experts and could be useful as clinical decision support tool for liver cirrhosis patients.

• Journal of Convergence for Information Technology
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• v.8 no.2
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• pp.19-27
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• 2018

The purpose of this study is to examine career maturity, self - management, and university life satisfaction according to general characteristics of college students. 403 students from Daegu and Gyeongbuk provinces were analyzed and analyzed by hierarchical multiple regression analysis focusing on factors such as general characteristics, personality traits, career attitude and self - management. As a result, according to the frequency and general characteristics of university life satisfaction, overall university life satisfaction was 3.29 out of 5 out of 5, and fresh students were higher than second year students. Also, the more open the personality, the higher the sincerity. The more self - management is the student who manage the life, the better the proper behavior management and physical management. In addition, students with a lower level of personality and a higher degree of readiness were more satisfied with college life than attitudes toward career maturity than those with lower grades. Based on these results, students with friendly characteristics can prepare well in career attitude maturity It is important to guide students well so that they can improve their college life satisfaction.

• Industry Promotion Research
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• v.6 no.4
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• pp.59-68
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• 2021

This study has identified the effect of reminiscence-based collective art therapy on the depression, interpersonal relationships, and the subjective sense of happiness among the elderly with dementia. The study was conducted on 30 volunteers with dementia aged 65 or older attending the S Weekly Care Center located in S-gun as subjects during the period between November 7, 2020 and January 2, 2021 with one session week for a total of 12 sessions. The SPSS 24.0 statistics program has been used for various data analyses, including confidence verification, cross tabulation analysis independent sample T-test, 3×2 multi-variant analysis, and the intergroup independent sample T-test between the groups. The study findings are as follows, First, the collective art therapy based on reminiscence therapy is effective in reducing the depression among the elderly with dementia. Second, the collective art therapy based on reminiscence therapy is effective in promoting interpersonal relationships among the elderly with dementia. Third, the collective art therapy based on reminiscence therapy is effective in improving the subjective sense of happiness among the elderly with dementia. These study findings are meaningful in that they have provided an informative basic data on the reminiscence-based collective art therapy.

• Clinical and Experimental Pediatrics
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• v.49 no.12
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• pp.1363-1366
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• 2006

Aneurysmal dilatation of the ductus arteriosis has been considered a rare but potentially fatal abnormality. The mechanism of ductal aneurysmal formation remains uncertain. Plain chest radiography has proven helpful in the diagnosis of ductus arteriosus aneurysm (DAA), before the application of transthoracic echocardiography. The transthoracic echocardiography is an important tool for the diagnosis and follow-up of DAA. We present a case of congenital ductus arteriosus aneurysm in a newborn, that was an incidental discovery. The diagnosis was made by echocardiography, three-dimensional surface rendering computed tomography (CT), and spontaneous regression after four weeks of follow-up.

• Journal of the Korean Orthopaedic Association
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• v.55 no.4
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• pp.338-342
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• 2020

Periosteal chondroma is a rare, slow-growing, benign cartilaginous tumor that develops between the periosteum and cortex, but there are no reports of multiple periosteal chondroma of the toes. A 19-year-old male presented with a palpable mass of the right fourth toe with tenderness for one year. A radiology examination revealed multiple, radio-lucent lesions with mild cortical irregularity. The magnetic resonance imaging findings were chondrogenic tumors with multiple, well-defined T1-low and T2-high signal enhanced lesions involved in the fourth proximal, middle, and distal phalanges. The tumors were removed by a surgical resection and curettage. Histologically, the tumors were proven to be periosteal chondroma.

• Journal of The Korean Association For Science Education
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• v.32 no.5
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• pp.866-878
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• 2012

The Natural Science High School is specialized in vocational education or training related to natural sciences such as biology or chemistry. Therefore, natural science high school students are expected to possess a high level of science learning motivation. This study aims to explore natural science high school students' level and structure of science learning motivation by comparing students in general high school. One hundred ninety three students from a natural science high school and 208 from a general high school participated in this study. We administered a questionnaire that consisted of seven science motivation components: 1) career motivation; 2) science grade motivation; 3) understanding the relevance of scientific knowledge; 4) need for learning science; 5) self-determination; 6) self-efficacy; and 7) attitudes toward science class. We employed independent t-test, path analysis, bivariate correlation, and stepwise multiple-regression for the statistical analyses. Our findings illustrated that the natural science high school students' levels on all seven variables were significantly lower than the general high school students.' The path analysis illustrated that career motivation and science grade motivation had relatively stronger influence on self-determination and self-efficacy in the natural science high school student sample than in the general high student sample. The explanatory powers of four independent variables (career motivation, science grade motivation, understanding the relevance of scientific knowledge, and need for learning science) predicting self-determination and self-efficacy were 30% higher in the natural science high school student sample than in the general science high student sample. These results suggested that natural science high school students' science learning motivation may be easier to change by extrinsic motivations such as career and science grade motivation.