• Elastomers and Composites
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• v.54 no.2
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• pp.156-160
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• 2019

The changes in the dispersion of carbon black in liquid polyisoprene under shear flow with time have been investigated by time-resolved ultra small-angle X-ray scattering (USAXS) method. The analyses of USAXS profile immediately after the start of shear flow clarified that the aggregates of carbon black with a mean radius of gyration of 14 nm and surface fractal dimension of 2.5 form the fractal network structure with mass-fractal dimension of 2.9. After the application of the shear flow, the scattering intensity increases with time at the observed whole entire q region, and then the a shoulder appears at $q=0.005nm^{-1}$, indicating that the agglomerate is broken and becomes smaller by shear flow. The analysis by the Unified Guinier/Power-law approach yielded several characteristic parameters, such as the sizes of aggregate and agglomerate, mass-fractal dimension of agglomerate, and surface fractal dimension of the primary particle. While the mean radius of gyration of the agglomerate decreases with time, the mean radius of gyration of the aggregate, mass fractal dimension, and surface fractal dimension don't change with time, indicating that the aggregates peel off the surface of the agglomerate.

• The Journal of the Petrological Society of Korea
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• v.15 no.3 s.45
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• pp.154-166
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• 2006

Though there are more than 600 active and non-active dimension stone quarries in Korea, most quarries are small-scaled and non-active. Main dimension stone belt in Korea is distributed in the Wonju-jecheon-Mungyeong-Geochang-Jinan-Nanwon-Geogumdo area with NNE direction, which occupies about 50% of domestic dimension stone quarries. The other dimension stone belts occur in the Gangyeong-Iksan-Gimje area, the Pocheon-Ujeongbu area and the Boryeong area. The dimension stones in Korea have been produced from at least fifteen rock types: granite, diorite, syenite, gabbro, homblendite, basalt andesite, rhyolite, tuff felsite, sandstone, marble, gneiss, schist and slate. However, seven or eight rock types such as granite, diorite and marble are currently produced. The dimension stones are quarried out 87% from plutonic rocks (mainly granite and diorite), 6% from sedimentary rocks (mainly sandstone), and 3% from metamorphic rocks (mainly marble). Main rock types of the dimension stones are variable with respect to their production locality. In the Jeollanam-do area, most dimension stones are produced from diorite. Marble is mainly produced from the Gangwon-do and Chungcheongbuk-do areas. Black sandstone is exclusively quarried out from the Chungcheongnam-do area. Granite is most abundant dimension stone in Korea. Above 50% of the domestic dimension stones are medium-grained to coarse-grained granitic rocks, but fine-grained granite dimension stones have 10% of distribution. The color of the dimension stone varies with rock types. Most granite dimension stones have dominant colors of whitish gray and gray, which are produced from the Wonju, Gapyeong, Iksan, Namwon and Geochang areas. Pink-colored granites are rarely produced from the Mungyeong area.

• Journal of Home Health Care Nursing
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• v.8 no.2
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• pp.135-147
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• 2001

The aim of this descriptive study was to identify the impact of chronic illness on children and their families. Mothers of 177 children with chronic disease were recruited from aged one to 17 years hospitalizing the pediatric nursing unit at one university hospital. 28 questions. a self-complete maternal questionnaire developed by researchers based on literatures and 'The Impact of Childhood Illness Scale' (Hoare & Russell, 1995) assess four aspects of the child's and family's lifestyle with two dimensions for each question. the frequency of the problem and its importance of concern that it cause. In the data analysis. Pearson correlation coefficients and analysis of variance were used to test any association and a statistical comparisons. between individual variables and the impact on child's and family's lifestyle. The results were as follows: 1) There were the higher mean scores on the importance dimension than on the frequency dimension on total impact on child's and family's lifestyle. On the importance dimension. mothers had much higher levels of concern about impact on child's development and adjustment among subscales. On the frequency dimension, mothers had much higher levels of concern about impact on the family daily living on subscales. 2) The impact on child's and family's lifestyle related on individual variables were: (1) On the importance dimension. there was statistically significant low in the impact on child's development and adjustment among subscales in older parent group compared with it of younger parent group. (2) On the frequency dimension. there were statistically significant high in the impact on child's development and adjustment among subscales in the children with leukemia or cancer compared with it of the other children who had another chronic illnesses. And there were statistically significant high in the impact on child's development and adjustment among subscales in less than high school educated mothers compared with it of mothers who was educated college level. (3) On the frequency dimension. There were statistically significant high in the impact on family's daily living among subscales and total impact on child's and family's lifestyle in female children. (4) There was positive correlation between impact on parents daily living and frequency of child's hospitalization on the frequency dimension. but there was negative correlation between the two variables on the importance dimension. (5) There was positive correlation between impact of chronic illness and its treatment and duration of child's hospitalization on the frequency dimension. In conclusion. these results were reflected by the high level of concerns about impact on child's development and adjustment although mothers had frequently responded about the impact on the family daily living. We suggest consistent intervening program that help the family empowering to make children live with and adjust to their chronic illnesses from the point of diagnosis and after discharge from the hospital. We also suggest these results can be utilized as a useful data in the practice of home health nursing for children who have chronic illnesses and their families.

• The Journal of Korean Academy of Prosthodontics
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• v.50 no.3
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• pp.198-203
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• 2012

Excessive occlusal wear results in unacceptable damage to the occluding surfaces, and can cause pulpal injury, occlusal disharmony, impaired function, and aesthetic deformity. Patients with severely worn dentition need to be classified as several categories relative to the vertical dimension of occlusion (VDO) and the interocclusal distance for the prosthetic space. When treating patients classified as those who have excessive wear without loss of occlusal vertical dimension but with limited space, we could consider treating them at an increased vertical dimension of occlusion. Treatments at an increased vertical dimension of occlusion may provide stability, given that the amount of its increase was minimal, and a perfected occlusion was achieved after enough stabilization period. A 50-year-old male visited the department of Prosthodontics in Yonsei University Dental Hospital with the chief complaint of worn teeth on lower anterior area. Reconstruction at an increased vertical dimension of occlusion was planned. After the compatibility of the new vertical dimension of occlusion had been confirmed under interim fixed restorations, definitive fixed restorations composed of full-contour monolithic zirconia prostheses were placed. This case presents that a satisfactory clinical result was achieved by restoring the worn dentition at an increased vertical dimension of occlusion with an improvement in esthetics and function.

• Journal of the Korean Wood Science and Technology
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• v.38 no.6
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• pp.470-479
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• 2010

In this study, the visual grading based on the visual characteristics and structural timber bending test were conducted for domestic yellow poplar dimension lumber. Structural performance of domestic yellow poplar dimension lumber was conducted through the evaluation of strength and stiffness. Visual grading rule of yellow poplar dimension lumber did not exist in Korea. Visual grading of yellow poplar dimension lumber was performed according to the NSLB (Northern Softwood Lumber Bureau) standard grading rules including several hardwood dimension lumber. The allowable bending stress was calculated from the results of a visual grading. Compared with NDS (National Design Specification), the yellow poplar dimension lumber showed enough strength for structural uses. In addition, the visual grading was performed according to the KFRI (Korea Forest Research Institute) grading rule to calculated allowable bending stress and to evaluated the feasibility. The yellow poplar was classified into the pine groups by the KFRI criteria regulated by specific gravity. Allowable bending stress based on weibull distribution had became highly than KFRI criteria, as No. 1 (10.0 MPa), No. 2 (7.4 MPa) and No. 3 (4.1 MPa). And the availability of yellow poplar dimension lumber for structural uses had been confirmed. The Modulus of Elasticity (MOE) of domestic yellow poplar dimension lumber had not met the NDS and KFRI criteria. However, for the use of domestic yellow poplar, average values of MOE which obtained through this test were suggested as design value for domestic yellow poplar. Design values were supposed No. 1, 2 (9,000 MPa) and No. 3 (8,000 MPa).

• The Journal of the Petrological Society of Korea
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• v.24 no.3
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• pp.273-289
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• 2015

This study used the petrological features and the whole rock susceptibility characteristics suggest ways to determine the domestic dimension stones and Chinese similar dimension stones. In addition, this study compare the intrusive period by measuring the zircon U-Pb age of these stones. Result of comparing the petrological feature, with the exception of Macheon stone and Boryeong stone to show the differences in mineral composition and texture under a microscope, the domestic dimension stones and Chinese similar dimension stones exhibit substantially the same petrological feature. According to the measurement results for the whole rock magnetic susceptibility, Goheong, Iksan, Pocheon stones are the similar as Chinese dimension stones, and other stones are easily distinguished. The zircon U-Pb age results for Geochang, Iksan, and Pocheon stones are equivalent to the Jurassic Daebo granites and G603, G633, G655 are the Cretaceous granites. Therefore, the domestic dimension stones and Chinese similar dimension stones can be clearly determined by the zircon U-Pb age results.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.21 no.1
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• pp.81-87
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• 2003

It is very difficult assignment that grasp three-dimensional real life in Web base network environment. But, the recent simulation tools embody third dimension elements within 2 dimensions screen that is limited through third dimension implementation technology. Many GIS tools are offering excellent functions for third dimension data creation. But, research about design of third dimension GIS that use virtual reality technique in Web environment is status that is unprepared. So, in this research embodied third dimension topography map using virtual reality modelling language to produce active third dimension VR map that can supply visual information for direction, visual point that want in World Wide Web without support of expensive Map exclusive use program. And these 3D Web-Map is thought that possibility is enough as next generation map medium.

• Imaging Science in Dentistry
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• v.35 no.1
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• pp.41-46
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• 2005

Purpose : The purpose of this study was to investigate whether the fractal dimension and radiographic image brightness of periapical radiograph were useful in predicting osteoporosis. Materials and Methods : Ninety-two postmenopausal women were classified as normal, osteopenia and osteoporosis group according to the bone mineral density of lumbar vertebrae and periapical radiographs of both mandibular molar areas were taken. The ROIs of 358 areas were selected at periapical and interdental areas and fractal dimension and radiographic image brightness were measured. Results : The fractal dimension in normal group was significantly higher than that in osteoporosis group at periapical ROI (P < 0.05). The radiographic image brightness in normal group was higher than that in osteopenia and osteoporosis group. There was significant difference not only between normal and osteopenia group (P < 0.05) but also within osteopenia and osteoporosis group (P< 0.01) at periapical ROI. Significant difference was observed not only between normal and osteopenia group but also between normal and osteoporosis group at interdental ROI (P< 0.01). Positive linear relationship was weakly shown at Pearson correlation analysis between fractal dimension and radiographic image brightness. BMD significantly correlated with fractal dimension at periapical ROI (P< 0.01), and BMD and radiographic image brightness significantly correlated at both periapical and interdental ROIs (P< 0.01). Conclusion : This study suggests that the fractal dimension and radiographic image brightness of periapical ROI may predict BMD. (Korean J Oral Maxillofac Radiol 2005: 35 : 41-6)

• The Journal of Korean Academy of Prosthodontics
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• v.56 no.1
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• pp.56-63
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• 2018

Severe dental attrition causes pathological changes of the tooth, collapsed occlusion, and functional and aesthetic complications and can also result in a decrease in occlusal vertical dimension. Before increasing the vertical dimension with full-mouth rehabilitation, it is important to determine the amount of vertical dimension through accurate diagnosis. In this case, a 77 year old elderly male patient on anticoagulant medication with generalized attrition and fracture of teeth was treated with full-mouth rehabilitation in order to recover vertical dimension and aesthetics. Accurate clinical and radiographic examination, diagnostic, wax-up, and occlusal vertical dimension evaluation were step by step performed considering pre-medical history and old age. Patient adaptability was evaluated using an occlusal splint and interim restoration. After 3 months of stabilization with interim restoration, definitive prostheses were fabricated. Satisfactory functional and esthetic outcomes are observed after 6 months of follow up.

• Journal of Science Education
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• v.36 no.2
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• pp.341-353
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• 2012

The purpose of this study is to explore how science teachers' views about physics and biology are different. From a survey of 45 science teachers who majored in physics, this study found that their views about physics were closer to the experts' views than their views about biology. But it seemed that their views about neither physics nor biology were similar to the experts' views. Compared their views about physics with their views about biology in six dimensions, in four dimensions including structure dimension, methodology dimension, validity dimension, and reflective thinking dimension, the scores of the views about physics were higher, in learnability dimension, the scores of the views about biology were higher, and in personal relevance dimension, the scores of the two kinds of views were similar. Specially the their views about physics in learnability dimension were closer to novices'. In addition, science teachers majored in physics seemed to think that compared with biology, physics is coherent, systematic and reasoning, but it is not learnable.