• The Korean Journal of Nuclear Medicine
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• 제17권1호
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• pp.55-62
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• 1983

In 16 volunteers without clinical or laboratory evidence of liver disease, liver volume was determined using single-photon emission computed tomography(ECT). This technique provided excellent object contrast between the liver and its surroundings and permitted calculation of liver volume without geometric assumptions about the liver's configuration. Reproducibility of results was satisfactory, with a root-me an-square error of less than 2% between duplicate measurements in 16 individuals. The volume measurements were validated by the use of phantoms.

• Journal of Internet Computing and Services
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• 제20권6호
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• pp.47-54
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• 2019

Social dredging of various river facilities, such as dams and agricultural reservoirs currently being constructed, should be done to ensure stable reservoirs. However, it is difficult to find a system that tells the exact amount of water in real-time in a reservoir or dam. These measurements require an automated system to collect and analyze highly accurate data in real time. In this study, we propose a method to measure the amount of water and soil of reservoir in real time through multi-division volume calculation using a drone, and this method can detect sediment conditions in real time and determine the exact timing and scale of dredging.

• The Journal of Advanced Prosthodontics
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• 제12권4호
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• pp.204-209
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• 2020

PURPOSE. Prevention of xerostomia and stress is important to prolong healthy life expectancy and improve the quality of life. We aimed to investigate the effects of tongue rotation exercise for increasing salivary secretions and stabilizing salivary stress hormone levels. MATERIALS AND METHODS. Twenty four participants without subjective oral dryness were enrolled. The exercises comprised tongue rotation exercise and empty chewing. The salivary stress hormone level was measured using a Salivary Amylase Monitor. Unstimulated whole saliva volume and salivary amylase activity were measured before tongue rotation exercise or empty chewing and subsequently 5, 10, and 15 minutes after these exercises. Differences in the rates of change of unstimulated whole saliva volume and salivary amylase activity were analyzed by repeated measure analysis of variance. RESULTS. Statistically significant differences among the rates of change were not observed after empty chewing for unstimulated whole saliva volume and salivary amylase activity at the four measurement times. However, the rate of change of unstimulated whole saliva volume and salivary amylase activity were statistically significantly different among the four time points: before the tongue rotation exercise and 5, 10, and 15 minutes post-exercise (P<.05 and P<.01, respectively). CONCLUSION. Tongue rotation is effective in increasing saliva secretion, reducing stress, improving oral function, and extending healthy life expectancy.

• Proceedings of the SAREK Conference
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• 대한설비공학회 2007년도 동계학술발표대회 논문집
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• pp.652-657
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• 2007

This paper is an interim report on the investigation of thermodynamic properties of $CO_2$/oil mixture refrigerant. First, liquid density of POE (poly-ol ester) and PAG (poly alkylene glycol) were measured and expressed as a function of temperature. Then, a solubility equation was developed which enables us to calculate the weight fraction of $CO_2$ for the mixture in a liquid state. An experimental apparatus with a cell was constructed to measure P-$\upsilon$-T-$\chi$ data for $CO_2$/oil mixture. The volume of the cell was determined using a certain formula considering change in volume as a function of temperature and pressure. Then, experimental data were obtained over the temperatures $40^{\circ}C$, $50^{\circ}C$, $60^{\circ}C$, $70^{\circ}C$ and $80^{\circ}C$ with various mole fractions. Finally, assuming a primitive model of ideal gas, the volume of $CO_2$/oil mixture was predicted with a relatively larger error of 5.05% for $CO_2$/PAG and 8.81% for $CO_2$/POE. The volume of $CO_2$/oil mixtures would be better predicted using an appropriate equation of state, of which results will be reported soon.

• Proceedings of the KIEE Conference
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• 대한전기학회 1987년도 전기.전자공학 학술대회 논문집(I)
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• pp.311-315
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• 1987

In this paper an efficient algorithm to estimate the volume and surface area and the reconstruction algorithm for 3-dimensional graphics are presented. The graph theory is used to estimate the optimal quantitative factors. To improve the computing efficiency, the algorithm to get proper contour points is performed by applying several tolerances. The search and the given arc cost is limited according to the change of curvature of the cross-sectional contour. For mathematical model, these algorithms for volume estimation based on polyhedral approximation are applied to the selected optimal surface. The results show that the values of the volume and surface area for tolerances 1.0005, 1.001 and 1.002 approximate to values for tolerances 1.000 resulting in small errors. The reconstructed three-dimensional images are sparse and consist of larger triangular tiles between two cross sections as tolerance is increasing.

• Korean Journal of Soil Science and Fertilizer
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• 제48권5호
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• pp.505-508
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• 2015

Soil bulk density is a key parameter for soil physical property. Much root placed in rhizosphere soil lump, especially in grassland and orchard, makes it difficult to measure soil bulk density. This experiment was carried out to countermeasure the above drawbacks. Volume check apparatus using water-filling method was made of acryl for higher accuracy in bulk density measurement. 10 types of land cover, including bare, tall fescue, rye, and soybean, were used for determining the relationships between root and bulk density. In this study, higher root volume resulted in higher differences in bulk density between in-situ core soil and root-ridded core soil, which indicated the volume check apparatus through water-filling could be useful for increasing the accuracy of bulk density of soils with much root.

• Journal of the Korean Society of Manufacturing Process Engineers
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• 제21권9호
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• pp.85-91
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• 2022

The demand for electric vehicles has increased because of environmental regulations. The lithium-ion battery, the most widely used type of battery in electric vehicles, is composed of a cathode, an anode, and an electrolyte. It is manufactured according to the pole plate, assembly, and formation processes. To improve battery performance and increase manufacturing efficiency, the manufacturing process must be optimized. To do so, simulation can be used to reduce wasted resources and time, and a finite-element method can be utilized. For high simulation quality, it is essential to reflect the material properties of the electrode by considering the pores. However, the material properties of electrodes are difficult to derive through measurement. In this study, the representative volume element method, which is a homogenization method, was applied to estimate the representative material properties of the electrode considering the pores. The representative volume element method assumes that the strain energy before and after the conversion into a representative volume is conserved. The method can be converted into one representative property, even when nonhomogeneous materials are mixed in a unit volume. In this study, the material properties of the electrode considering the pores were derived. The results should be helpful in optimizing the electrode manufacturing process and related element technologies.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 한국정보통신학회 2014년도 추계학술대회
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• pp.981-984
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• 2014

Volumetric measurement of hippocampus using IBASPM, the 20's normal adults 10 people's brain images were acquired in order to assess the changes according to the type of the Atlas. Images was obtained using MPRAGE of a 3-D gradient echo pulse sequence on Head matrix coil of 1.5T MRI system. The results of Paired t-test using obtained volume of hippocampus depending on the type of the Atlas, Atlas69-Altas84, Atlas69-Atlas116(p=0.729, 0.729) in the left hippocampus and Atlas69-Atlas84, Atlas69-Atlas116(p=0.219, 0.219) in right hippocampal formation were no significant differences but in the area except this, there was significant difference(p=0.000). The volume of the hippocampus using Atlas84 and Atlas116, represented the same value and there was no significant difference. In the image analysis using the overlay of atlas image and original image, Atlas71 could be found that the area of hippocampus did mismatch. In the case of atlas used in this study, because it has been developed by the westerners, there are differences between brain of asian. It would be needed to development of new Atlas for high accuracy measurement of the volume of hippocampus.

• Journal of the Korean Society of Clothing and Textiles
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• 제34권3호
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• pp.385-392
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• 2010

The breast types of middle-aged women of 80A (formerly 80B) size were classified through a 3D scanned nude body. Thirty seven measurements including the radius of curvature, surface area, volume, surface length, and breast displacements were used as input variables. We extracted five main factors through the factor analysis of the measurements and classified 36 subjects into 3 clusters through the cluster analysis. As a result of the factor analysis, the size of the breast, breast sag, the curvature of the inner and the outer breast curve, the width of the breast, and the nipple direction were found as the main factors. For the results of the classification of breast types, Cluster 1 was characterized by narrow breast width and unsymmetrical under the breast curve, whereas Cluster 2 was a wide and sagged shape. Cluster 3 was classified into big breast volume and symmetrical under-breast curve. The results are useful to the product development of high quality brassieres which reflect the 3D characteristics of breast types of middle-aged women.

• Transactions of the Korean Society of Mechanical Engineers B
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• 제29권9호
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• pp.1065-1073
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• 2005

The thermal conductivity of water- and ethylene glycol-based nanofluids containing alumina $(Al_2O_3)$, zinc oxide (ZnO) and titanium dioxide $(TiO_2)$ nanoparticles is measured by varying the particle diameter and volume fraction. The transient hot-wire method using an anodized tantalum wire for electrical insulation is employed for the measurement. The experimental results show that nanofluids have substantially higher thermal conductivities than those of the base fluid and the ratio of thermal conductivity enhancement increases linearly with the volume fraction. It has been found that the ratio of thermal conductivity enhancement increases with decreasing particle size but no empirical or theoretical correlation can explain the particle-size dependence of the thermal conductivity. This work provides, for the first time to our knowledge, a set of consistent experimental data over a wide range of nanofluid conditions and can therefore serve as a basis for developing theoretical models to predict thermal conduction phenomena in nanofluids.