• The Korean Journal of Nuclear Medicine Technology
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• v.12 no.1
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• pp.27-32
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• 2008

Purpose: The evaluation of SUV (Standardized Uptake Values) for quantitative analysis in PET exam is the most significant. In PET exam, we make attenuation correction images by using $^{68}Ge$, $^{137}Cs$ or CT data. At this time, a distorted attenuation map affects quantitative analysis. After the exam using barium-sulfate and high density of barium contrast make attenuation map distorted. And then it brings bed influences on SUV. The aim of this study is to verify the relationship between high density barium-sulfate and SUV in PET exam. Materials and Methods By using $^{18}F$-FDG, we made barium-sulfate powder, density of 0, 1.5, 3, 5, 10 and 15% respectively and acquired PET and PET/CT images per each density. And we examined SUV variations from PET and PET/CT images according to differences of barium's density. Moreover, we finally calculated SUV causing variations in HU (Hounsfield Units) values to justify whether the differences of barium density bring any changes in PET/CT exam. Results: From PET images acquired from transmission scan with $^{68}Ge$, we got SUV figures from 6.46 to 6.8 in barium density between 0 to 15 percent. On the other hand, In PET images acquired from Tx scan that using CT, SUV was 6.77 to 23.73, derived from the same barium density. And CT HU values range from 29 to 2004. Conclusion: PET images from Tx data using $^{68}Ge$ weren't affected by barium density and had no differences in SUV. But in the PET/CT images using CT Tx data, there's considerable variations in HU and SUV values according to a difference of barium density in HU values. To perform a precise examination, barium sulfate should be removed from a human body before performing a PET exam.

• Journal of the Korean Society of Safety
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• v.31 no.5
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• pp.1-6
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• 2016

The performance of a set of low-cost optical components used for measuring the optical density of PM particles was evaluated in the present study. To this end, the set of low-cost optical components was replaced with that of general optical components used to measure the PM optical density under identical experimental conditions. The optical densities measured from the set of general optical components were then compared to those obtained from the set of low-cost optical components. While the optical density is measured, another key parameter, the dimensionless extinction constant of PM particles (which is needed to optically measure the PM concentration) was also determined in the present study. The experimental results indicate that the optical density and PM concentration measurements performed by low-cost optical components are feasible, producing trackable variations in the OD and concentrations compared to values obtained from the set of general optical components.

• The Korean Journal of Food And Nutrition
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• v.27 no.4
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• pp.732-741
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• 2014

Korean foods have the strengths to addresssome of the health problems of modern man. To assess the properties of Korean noodles, daily value %, DVS, DDS and energy density were compared between many kinds of noodles from around the world. Using a variety of reference materials, a nutritional database of noodles was built for this study. For carbohydrate, lipid, vitamin A, vitamin K, vitamin C, niacin, zinc, and copper, the daily values % of western noodles were significantly higher. Also, the serving size of Korean noodles was significantly small. Comparing the average energy density of the noodles, they showed $1.87{\pm}0.93kcal/g$ (Korean noodles), $2.42{\pm}1.08kcal/g$ (western noodles) and $1.84{\pm}0.84kcal/g$ (other noodles). The dietary fiber, polyphenols, and flavonoids content of the noodles showed no significant difference. Neither DVS nor DDS showed a statistically significant difference. In the Korean noodles, the GMDFV pattern showed a diverse choice of food groups. Korean noodles show a lower energy density, and the small serving size to have favorable for the prevention of obesity. Thus, Korean noodles are an excellent choice in terms of diversity and energy density.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.8
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• pp.1126-1130
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• 2003

The conditions of measurement for the determination of bulk density were evaluated to assess the bulkiness of 8 kinds of forage. The bulkiness of the forages was determined with 4 different sizes of forage samples with 7 different pressure application under air-dry and wet conditions. The dry bulk density (DBD) curvilinearly regressed with the pressure applied. The particle size of the samples and kinds of forage used in the present study did not affect changes in values of DBD determined under pressures over $20g/cm^2$ up to $200g/cm^2$. The values of the wet bulk density (WBD) increased as an increment of particle size, but were not always regressed on the particle size of the 8 kinds of forage. The DBD determined on 8 mm particles showed a higher correlation coefficient with neutral detergent fiber (NDF) contents. The DBD may be a useful tool for the assessment of NDF in forage, when it is determined under condition of a pressure of $100g/cm^2$ or over with a particle size of 8 mm. The WBD may not be utilized for the direct measurement of the physical characteristics of forage, but may be required a thorough consideration on water solubility of forages. Further studies are needed to clarify the DBD contribution to the prediction of forage intake by ruminants.

• Bulletin of the Korean Chemical Society
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• v.24 no.12
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• pp.1742-1750
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• 2003

In order to characterize the hydrophobic parameters of N-acetyl amino acid amides in 1-octanol/water, a theoretical calculation was carried out using a solvation free energy density model. The hydrophobicity parameters of the molecules are obtained with the consideration of the solvation free energy over the solvent volume surrounding the solute, using a grid model. Our method can account for the solvent accessible surface area of the molecules according to conformational variations. Through a comparison of the hydrophobicity of our calculation and that of other experimental/theoretical works, the solvation free energy density model is proven to be a useful tool for the evaluation of the hydrophobicity of amino acids and peptides. In order to evaluate the solvation free energy density model as a method of calculating the activity of drugs using the hydrophobicity of its building blocks, the contracture of Bradykinin potentiating pentapeptide was also predicted from the hydrophobicity of each residue. The solvation free energy density model can be used to employ descriptors for the prediction of peptide activities in drug discovery, as well as to calculate the hydrophobicity of amino acids.

• Journal of the Korean Society of Food Culture
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• v.11 no.1
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• pp.53-59
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• 1996

This study was conducted to standardize the cooking methods of Omija-Pyuns and to investigate the effect of different starch densities (6% 7%, 8%, 9%) on the texture and taste of Omija-Pyuns. The results of these studies were as follows: 1) It was better for Omija to soak for 18 hours. The most favorite Mungbean starch density of 7% of Omija-Pyuns has the degree of lightness of 18.90, the degree of redness of 19.18, and the degree of yellowness of 3.98. 2) The Brix of syrup used for Omija-Pyuns was 49.4%. 3) As a result of the measurement of texture through Instron, if Mungbean starch density is increased, its hardness also increase. Each of the Omija-Pyuns (6%, 7%, 8%, 9%, in density) has showed its effection (p<0.05). 4) The result of the sensory evaluation showed that the Omija-Pyuns produced with Mungbean starch density of 7% was most preferred in appearance and overall taste, but it did not show the statistical effection (p<0.05) from the Omija-Pyuns produced with Mungbean starch density of 8%. The flavour was highest in Omija-Pyuns of 6%, and as the density was increased, the flavour decreased.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2003.10a
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• pp.63-66
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• 2003

The effect of punching density and material composition on the tensile properties and optimum condition of manufacturing of carbon needle punched perform was studies. The interlaminar tensile strength were increased but the intralaminar tensile strength were decreased with increasing punching density. In the case of the performs composed of continuous oxi-PAN fabrics, there was a considerable improvement of the interlaminar and intralaminar tensile strength.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2010.11a
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• pp.1027-1028
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• 2010

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2007.11a
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• pp.197-198
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• 2007

• Proceedings of the Korean Geotechical Society Conference
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• 1996.10a
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• pp.227-236
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• 1996