• Journal of the Korean Society of Radiology
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• v.13 no.5
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• pp.675-681
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• 2019

The purpose of this study was to investigate the effect of increasing the amount of 3D volume imaging on the hand, knee, and foot human phantom in CT, After analyzing the data, three - dimensional volumetric images were implemented using MMWP program to evaluate reproducibility. First, the data amount of three human phantoms according to each increment was analyzed. Secondly, the reproducibility evaluation and the measured length were compared. As a result of analyzing the amount of image data for each phantom according to the increment, it was confirmed that the amount of data is reduced to about 1/10 when the increment is set to 1.0 mm as compared with the case where the increment is set to 0.1 mm. In the evaluation of the feasibility, gap was generated from 0.7mm for hand phantom, 0.6mm for knee phantom and foot phantom, and it was confirmed that even when the actual phantom and actual length were compared, the length was much different and the implementation was lowered. As the increment is closer to 1.0mm, the number of images is small and the 3D implementation time is small. Therefore, it is best to determine the increase before the gap of the image is generated and to apply the Increment for preoperative diagnosis. We hope that this study will be an indicator of the accurate increment setting when implementing 3D image through VRT Rendering after CT scan.

• Nuclear Engineering and Technology
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• v.27 no.3
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• pp.344-357
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• 1995

The gap conductance between the fuel and the sheath depends strongly on the gap width and has a significant influence on the amount of initial stored energy. The modified Ross and Stoute gap conductance model in ELESTRES is based on a simplified thermal deformation model for steady-state fuel temperature calculations. A review on a series of experiments reveals that fuel pellets crack relocate, and are eccentrically positioned within the sheath rather than solid concentric cylinders. In this paper, the hue recently-proposed gap conductance models (offset gap model and relocated gap model) are described and are applied to calculate the fuel-sheath gap conductances under experimental conditions and normal operating conditions in CANDU reactors. The good agreement between the experimentally-inferred and calculated gap conductance values demonstrates that the modified Ross and Stoute model was implemented correctly in ELESTRES. The predictions of the modified Ross and Stoute model provide conservative values for gap heat transfer and fuel surface temperature compared to the offset gap and relocated gap models for a limiting power envelope.

• Proceedings of the KWS Conference
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• v.43
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• pp.76-78
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• 2004

The phenomenon of weld shrinkage mainly occurs owing to residual stress by heating, which largely effects on welding quality, Actually as the shrinkage rate depends on the weld deposit amount, so it is desired that the sectional area of weld joint shall be reduced. In this respect the Electron beam welding has more profitable position compare to Narrow-gap TIG welding which is even superior to other arc welding processes. In case of thick austenitic stainless steel the shrinkage rate of Electron beam welding has about $10\%$ of Narrow-gap TIG welding's, which means that residual stress is a lot less than that of Narrow-gap TIG welding. And heat input and welded section area also indicate large difference between two processes.

• Journal of Veterinary Science
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• v.25 no.2
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• pp.26.1-26.6
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• 2024

Bone loss from the kerf of the sawblade may influence the final outcomes when employing three-dimensional-printed surgical guides. However, no studies have systematically addressed saw blade-induced bone loss. This study aims to quantify bone loss and propose a reduction guide to minimize the fracture gap. The postoperative gap tended to decrease as the amount of gap compensation increased. Osteotomy gaps can be attributed to the thickness of the saw blade, and the proposed methodology addresses this surgical error. Surgeons can proactively plan and design reduction guides with applied compensation using the method described in this study.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2003.05a
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• pp.164-167
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• 2003

Profile ring rolling process is simulated by using the general purpose commercial finite element analysis software MSC.Superform Because the deforming region is restricted to the vicinity of the roll gap, only a ring segment spanning the roll gap is analysed in order to save computation time and cost. A profile ring with an external round groove is chosen as an example to be analysed. The rolls with and without groove were analysed to compare the amount of side spread. It is found that the grooves in the rolls reduce the amount of side spread.

• Transactions of Materials Processing
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• v.12 no.7
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• pp.631-639
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• 2003

Ring rolling process is simulated by using the general-purpose commercial finite element analysis software, MSC.Superform. Because the deforming region is restricted to the vicinity of the roll gap, only a ring segment spanning the roll gap is analyzed in order to save computation time and cost. First, a plain ring rolling of rectangular cross-section is simulated. Comparisons between computation and experiment show good agreement in the cross-sectional configuration of the deformed ring. Then, a profile ring with an external round groove is analyzed. The rolls with and without groove have been analyzed to compare the amount of side spread. It is found that the grooves in the rolls are effective in reducing the amount of side spread.

• Journal of the Korean Society of Clothing and Textiles
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• v.29 no.11
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• pp.1399-1409
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• 2005

The purpose of this study was to analyze the shape of gathered skirts using a three-dimensional measurement system. And in this experiment, I try to accumulate three-dimensional data of wearing model and to figure out analyzing method made by shape of clothes. The experimental design consists of two factorial designs. I set up three different kinds of fabrics, ratio of gathers. Therefore nine samples were made. The instrument and tools for three-dimensional measurement was whole body 3D scanner. Analysis program used in experiment is RapidForm 2004 PP1 and Pattern Design 2000. Data analysis utilizes SPSS WIN 10.0 Package. T-test to effect an inspection of evidence, there was difference about measurement times. One-way ANOVA to analysis effect of gather made by gathering conditions. The following results were obtained; 1. As a result of inspecting an error several times using a three-dimension measurement system, convinced data was obtained. 2. At front, distribution of gap amount was larger than back. And as ratio of gathers increased, distribution of gap amount showed regularly. 3. After analyzing horizontal sectional figure of skirts, as a height of skirt changed from waist to the bottom of skirts, the results showed as follows. While section width, section thickness, node width, node depth increased, node count decreased. 4. With the horizontal section levels of gather skirt, the silhouette on middle hip section was similar with the silhouette of body line. And as ratio of gathers around hip section increased, nodes showed regularly. At the bottom of skirts showed different nodes by different gathering condition.

• Journal of the Korea institute for structural maintenance and inspection
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• v.25 no.6
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• pp.199-208
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• 2021

The extrudability of 3D printed concrete and its member strength can be highly influenced by water cement ratio (W/C) and printing time gap (PTG). In this study, mold cast specimens and 3D printed specimens were fabricated with variables of W/C ratio and PTG, and their shear bond strength and interlayer surface moisture content were measured and analyzed. The test results showed that the shear bond strength is greatly influenced by the amount of interlayer surface moisture. It is thus recommended that proper amount of interlayer surface moisture with respect to PTG needs to be maintained to have a required interlayer shear bond strength. In addition, further research is required to estimate the effect of many environmental factors that can influence the interlayer surface moisture content.

• Restorative Dentistry and Endodontics
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• v.20 no.2
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• pp.432-461
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• 1995

The basic principles in the design of Class II amalgam cavity preparations have been modified but not changed in essence over the last 90 years. The early essential principle was "extension for prevention". Most of the modifications have served to reduce the extent of preparation and, thus, increase the conservation of sound tooth structure. A more recent concept relating to conservative Class II cavity preparations involves elimination of occlusal preparation if no carious lesion exists in this area. To evaluate the ideal ClassII cavity preparation design, if carious lesion exists only in the interproximal area, three cavity design conditions were studied: Rodda's conventional cavity, simple proximal box cavity and proximal box cavity with retention grooves. In this study, MO amalgam cavity was prepared on maxillary first premolar. Three dimensional finite element models were made by serial photographic method. Linear, eight and six-nodal, isoparametric brick elements were used for the three dimensional finite element model. The periodontal ligament and alveolar bone surrounding the tooth were excluded in these models. Three types model(B option, Gap option and R option model) were developed. B option model was assumed perfect bonding between the restoration and cavty wall. Gap option model(Gap distance: $2{\mu}m$) was assumed the possibility of play at the interface simulated the lack of real bonding between the amalgam and cavity wall (enamel and dentin). R option model was assumed non-connection between the restoration and cavty wall. A load of 500N was applied vertically at the first node from the lingual slope of the buccal cusp tip. This study analysed the displacement, 1 and 2 direction normal stress and strain with FEM software ABAQUS Version 5.2 and hardware IRIS 4D/310 VGX Work-station. The results were as followed. 1. Rodda's cavity form model showed greater amount of displacement with other two models. 2. The stress and strain were increased on the distal marginal ridge and buccopulpal line angle in Rodda's cavity form model. 3. The stress and strain were increased on the central groove and a part of distal marginal ridge in simple proximal box model and proximal box model with retention grooves. 4. With Gap option, Rodda's cavity form model showed the greatest amount of the stress on distal marginal ridge followed by proximal box model with retention grooves and simple proximal box model in descending order. 5. With Gap option, simple proximal box model showed greater amount of stress on the central groove with proximal box model with retention grooves. 6. Retention grooves in the proximal box played the role of supporting the restorations opposing to loads.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.37 no.3
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• pp.292-296
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• 2024

In this study, Iron (III) oxide-hydroxide (δ-FeOOH) was successfully synthesized using hydrogen peroxide (H₂O₂) as an oxidizing agent. The synthesis of δ-FeOOH was carried out by controlling the amount of H₂O₂, and pure δ-FeOOH was successfully synthesized in ranges from 0.2 mL to 0.6 mL of H₂O₂. The size of the synthesized δ-FeOOH particles was compared by controlling the amount of oxidant H₂O₂. The average particle size of the synthesized pure δ-FeOOH particles increased from 875.1 nm to 897.2 nm as the amount of H₂O₂ was increased. The optical properties of δ-FeOOH synthesized under these specific conditions were investigated. All δ-FeOOH showed a similar trend of increasing and decreasing light absorption from 800 nm to 400 nm, although there was a slight difference in the amount of light absorption, with the largest amount of light absorption at 410 nm. The band gap energy of δ-FeOOH through the Tauc plot method was about 2.1~2.2 eV when H₂O₂ was 0.2~1.4mL. With a sufficient small particle size, simple control of that particle size, and a small band gap energy enough to absorb light in the visible spectrum, δ-FeOOH could be useful in a variety of applications, including photoelectrochemistry and battery electrodes.