• Journal of the Korean institute of surface engineering
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• v.36 no.3
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• pp.234-241
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• 2003

SiC nanorod was synthesized directly on Si substrate using hexamethyldisilabutane and Fe catalyst with (111) direction. Fe acted a liquid catalyst at growth condition. Grown SiC nanorod has about 30nm diameter and $5{\mu}m$ length. SiC nanorod growth was divided by trro regions with diameter distribution. This diameter distribution were occurred by surface deposition at as - grown nanorod's surface by limitation of growth rate. At higher temperature, these division not occurred. Growth temperature and flow rates affected diameter and morphology of nanorods. With increasing flow rate of source gas, nanorod's diameter increased because of deactivation effect. Case of the increasing temperature, growth rate increased so deactivation did not occurred.

• Journal of Technologic Dentistry
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• v.28 no.2
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• pp.347-353
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• 2006

The Purpose of this study was to compare the distribution of implant fixtures according to length and diameter between screw-retained and cement-retained implant-supported fixed prosthesis and to asses whether prosthesis retained types affected the selection of size of implant fixtures. This study presents a follow-up 2,416 implant-supported fixed type prosthesis that have been screw retained or cemented retained for about 10 years in 14 dental clinics. Included in the study were 458 men and 397 women and implant fixtures used in this study were screw retained type 1,057 and 1,359 of cemented retained type. The statistical results among the diameter types of fixture by prosthesis retained type was no significant difference noted (P= 0.809) and there was significant differences was enough to among the lengths of fixture by prosthesis retained type (P= 0.020). However there were no significant difference among the fixture diameter types and length by prosthesis retained type (P= 0.486). So there was not affected to prostheis fixation mechanism for the size of implant fixtures.

• Journal of Chest Surgery
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• v.32 no.5
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• pp.442-447
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• 1999

Introduction: Understanding the normal distribution of the tracheal diameter and crross- sectional area is one of the key elements in the management of various tracheal pathologies or tracheal reconstruction for the patients in growing age. However, data for Korean standard has been lacking. This study was designed to analyze retrospectively the distribution of tracheal diameter and cross-sectional area in young Koreans, which can afford fundamental data for the management of tracheal diseases. Material and Method: Of the patients who underwent computerized tomogram of the chest between May 1996 and August 1998, one hundred six young patients(age range: 0-20 years) were included. Patients with any conditions which might affect the tracheal cross-sectional area or diameter, such as tracheal disease, previous operation, mediastinal tumor, or obstructive lung disease were excluded from the study. Gender distribution was 69 males and 37 females. Tracheal diameters, anterior-posterior and transverse, were measured at the level of the thoracic inlet(level I) and the aortic arch(level II). Types of the trachea were divided into round, oval, or horseshoe shaped on cross-sectional view, and the dimension was calculated by using the equation of A=1/4$\pi$ab(A; area, $\pi$; 3.14, a; anterior-posterior diameter, b; transverse diameter). We analyzed the distribution of the diameter at each level and compared the cross-sectional area with respect to age and gender. A p-value lower than 0.05 wa considered significant. Result: The trachea of patients less than 5 years old were round in shape at both of level I and II, and no differences in cross-sectional area was observed between the levels(p=NS). As the age increased, the trachea become oval in shape at level I while it remained round in shape at level II(p=0.020). The tracheal diameter and cross-sectional area increased as the age increased with a linear correlation(r>0.9). In patients less than 5 years of age, female patients showed larger cross-sectional area than male patients (p=0.020), and it was reversed in patients older than 15 years of age(p=0.002). Conclusion: From the above results, we suggest chest computerized tomogram as a safe and reliable tool in measuring the tracheal diameter and cross-sectional area. We also provide the data as a standard for distribution of the tracheal diameter and cross-sectional area in young Korean population.

• Journal of radiological science and technology
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• v.21 no.2
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• pp.43-46
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• 1998

When a patient was irradiated with prosthetic hip, the dose distribution was changed according to inhomogeneous materials. The density, effective atomic number, and the composition of material had influence on absorbed dose distribution. In this study, the influence of inhomogeneous material(Ti) was measured using a polyethylene phantom, which consisted of various diameter of titanium, with film dosimetry. As a result, the backward dose showed 29.5% increas by backscattering, the forward dose showed 28% decreas by absorption, and the side dose showed 7% increas by scattering, when 25 mm diameter Ti was used. In addition forward dose was in inverse proportion to the thickness of prosthetic material. When the prosthetic hip of patient is in an irradiated field, we must carefully study the absorbed dose distribution.

• Journal of Korean Society for Atmospheric Environment
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• v.4 no.2
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• pp.28-37
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• 1988

Light scattering coefficient of visible light by atmospheric aerosol over the size range 0.01-10$\mu$m is determined from scattering efficiency and aerosol size distribution. Aerosol number distribution as a function of particle diameter dN/dlog D decreases rapidly as increasing particle size. Distribution of scattering coefficient d$\sigma_s/dlog$ D is mostly accumulated in diameter 0.1-2.0 $\mu$m showing its maximum in the vicinity of 0.6$\mu$m. This means that the visible light in the atmosphere is mainly scattered by these particles. Diurnal variation of scattering coefficient $\sigma_s$ appears its maximum in the morning, while minimum in the afternoon which agrees with the aerosol number distribution in the size range 0.1-2.0 $\mu$m.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.31 no.2
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• pp.116-126
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• 2009

The use of short implants has been accepted risky from biomechanical point of view. However, short implants appear to be a long term viable solution according to recent clinical reports. The purpose of this study was to investigate the effect of different diameter and length of implant size to the different type of bone on the load distribution pattern. Stress analysis was performed using 3-dimensional finite element analysis(3D-FEA). A three-dimensional linear elastic model was generated. All implants modeled were of the various diameter(${\phi}4.0$, 4.5, 5.0 and 6.0 mm) and varied in length, at 7.0, 8.5 and 10.0 mm. Each implant was modeled with a titanium abutment screw and abutment. The implants were seated in a supporting D2 and D4 bone structure consisting of cortical and cancellous bone. An amount of 100 N occlusal load of vertical and $30^{\circ}$ angle to axis of implant and to buccolingual plane were applied. As a result, the maximum equivalent stress of D2 and D4 bones has been concentrated upper region of cortical bone. As the width of implant is increased, the equivalent stress is decreased in cancellous bone and stress was more homogeneously distributed along the implants in all types of bone. The short implant of diameter 5.0mm, 6.0mm showed effective stress distribution in D2 and D4 bone. The oblique force of 100N generated more concentrated stress on the D2 cortical bone. Within the limitations of this study, the use of short implant may offer a predictable treatment method in the vertically restricted sites.

• Environmental Analysis Health and Toxicology
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• v.25 no.3
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• pp.215-222
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• 2010

The market size of engineered nanoparticles is rapidly increasing due to the fast application of nanotechnologies into different industries and consumer products. The development of new technology and materials has improved human's quality of life, but it also entails the possibility of exposure to new materials. In this study, we compared the distribution in the body by the inflow of silver nanoparticles having another diameter and shape at 1 h or 24 h after injection via the tail vein. And, we compared the cell composition and cytokine concentration in BAL fluid, and histopathological changes. As results, discharge of silver nanoparticles having small diameter and sphere shape was more rapid than that of big diameter or plate shape. It is estimated that the toxicity in liver and lung was proportional to accumulation level. The persistence of inflammation was also longer in mice treated with plate shape. Consequently, we suggest that the first choice of silver nanoparticles having small diameter and sphere shape in applying is desirable.

• Korean Journal of Plant Resources
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• v.12 no.4
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• pp.297-302
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• 1999

This study was carried out to find morphological characters of flower and its distribution in mixed population of Paeonia lactiflora Pallas. In distribution of flowering periods, early, medium, and late matured type were 18%, 56%, and 26%, respectively. Flowering duration was less than eight days in 9% of flowers. In next 9 to 11 days, 12 to 14 days and more than 15 days showed, 50%, 37% and 4% respectively. For flower sizes, small size below 9cm diameter were 11%, medium size between 9 to 13cm diameter and large size above 13cm diameter were 65% and 24%, respectively. Among six kinds of flower colors - red, red pink, pink, light pink, pale yellow and white, pink color flowers was dominant, showed 56%. In flower types, single flower was 76%, and anemone, crown, bomb and japanese types were also present. Flower stem diameter were positively correlated with flowering duration, flower size and number of stamens, and negatively correlated with number of stamens and pistils, number of pistils and petals.

• Journal of Advanced Information Technology and Convergence
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• v.10 no.1
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• pp.25-36
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• 2020

Motivation: Fibers as the extracellular filamentous structures determine the shape of the cytoskeletal structures. Their characterization and reconstruction from a 3D cellular image represent very useful quantitative information at the cellular level. In this paper, we presented a novel automatic method to extract fiber diameter distribution through a pipeline to reconstruct fibers from 3D fluorescence confocal images. The pipeline is composed of four steps: segmentation, skeletonization, template fitting and fiber tracking. Segmentation of fiber is achieved by defining an energy based on tensor voting framework. After skeletonizing segmented fibers, we fit a template for each seed point. Then, the fiber tracking step reconstructs fibers by finding the best match of the next fiber segment from the previous template. Thus, we define a fiber as a set of templates, based on which we calculate a diameter distribution of fibers.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.14 no.1
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• pp.2-8
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• 2006

Numerical analysis of the flow field in the reactive medium of End-Burring combustor is studied in order to investigate the combustion characteristics of hybrid combustion. The main part of this study is focused on the port diameter effects of oxidizer injector on the temperature distribution within the reactive field. It is found that the case having the largest port diameter(25 mm) delivers the optimum conditions for the design of End-Burring combustor where the predicted temperature field showed the most acceptable distribution.