• Design & Manufacturing
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• v.16 no.2
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• pp.39-45
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• 2022

Sheet Metal Forming by Press Forming Process takes a lot of time and cost from mold design to manufacturing. Therefore, all of die-makers are continuously conducting research to reduce the number of mold processes or the size of blanks to reduce costs. In the case of Forming complex shapes such as automobile component, wrinkles and cracks occur, so draw beads are used. Draw beads play an important role in suppressing the inflow of materials and minimizing the size of blanks. Factors that affect material flow include draw bead, blank holding pressure, lubricant, and surface roughness of punch and die. Most of the factors affect friction. In this study, after classifying circular beads and rectangular beads in cylindrical drawing molds using the AutoForm analysis program, the factors affecting the material inflow were considered.

• Proceedings of the KWS Conference
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• 1997.10a
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• pp.210-215
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• 1997

• Microbiology and Biotechnology Letters
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• v.18 no.4
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• pp.352-359
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• 1990

The synergistic effect of glucoamylase and a -amylase on the hydrolysis of raw corn starch in an agitated bead reaction system was studied by investigating the changes of sugar profiles, the granular structure, particle size distribution, and X-ray diffraction pattern of residual raw corn starch. The enzymatic hydrolysis of raw corn starch was greatly enhanced by synergistic effect of glucoamylase and $\alpha$ -amylase. Even though the sugar profiles were mainly determined by the mixing ratio of glucoamylase and $\alpha$-amylase; raw starch was mainly converted to glucose directly without accumulation of any significant amount of oligosaccharides. The cavity formation and fragmentation phenomena of raw corn starch granule subjected to enzyme reaction were analyzed by means of SEM and the particle size distribution. The X-ray diffraction pattern of raw starch was not changed at the initial stage of reaction but slightly changed at the late stage of hydrolysis, which may be caused by the preferential degradation of amorphous region by enzymatic reaction, not by the destruction of microcrystalline structure of raw corn starch.

• Applied Chemistry for Engineering
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• v.18 no.4
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• pp.386-390
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• 2007

In this study, polyurethane prepolymers were synthesized from polycaprolactonediol (PCDs. M.W. 530, 830, 1000, 1250, and 2000) and polycaprolactonetriol (PCTs. M.W. 300 and 900), and hexamethylenediisocyanate (HMDI). Polyurethane beads was prepared from the different prepolymers by a two-step suspension polymerization. The particle size of polyurethane beads was investigated by particle size analyzer. The beads were $10{\sim}30{\mu}m$ in size. The structure of beads was confirmed by FT-IR spectrometer. Their thermal properties were analyzed by TGA. Glass transition temperatures ($T_g$) of the beads were in the range of $-23{\sim}-53^{\circ}C$ and decreased with the increase of the PCD molecular weight. In order to prevention the cohesion of beads, the beads were coated with tetraethoxysilane (TEOS).

• The Korean Journal of Food And Nutrition
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• v.15 no.2
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• pp.89-96
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• 2002

The adsorption characteristics of sodium chloride into Ca-alginate beads have been investigated and the result were as follows: Sodium chloride uptake by Ca-alginate beads increased with time. The highest uptake volume of sodium chloride was 4.2g after 10 minutes. The uptake volume by Fe, Ca, Ba, and Sr-alginate beads was 5.6g, 4.2g, 4.2g and 4.0g, respectively but in case of Fe-alginate beads, the induced hydrogel beads were very fragile and the strength of Fe-alginate beads were weaker than Ca- and Ba-alginate beads. Mg-alginate bead was not formed and Ca-, Ba- and Sr-alginate beads had a similar uptake volume about 4.2g, respectively. The uptake volume of sodium chloride by CaCl$_2$concentration(0.1M. 0.2M and 1M), curing solution, was 4.8, 4.2g and 4.1g, respectively. The uptake volume by sodium alginate concentration(0.6%, 1% and 2%) was 2.8g, 4.0g, and 4.4g, respectively and Ca-alginate bead size was not effected in uptake sodium chloride. The uptake rate on initial sodium chloride concentration(4%, 8%, 12% and 16%) was 30%, 28%, 27% and 25%, respectively. The uptake rate on basic pH(10.0) was higher than when compared to other neutral pH(6.8) and acidic pH(4.0). The initial uptake velocity of sodium chloride from immobilization beads with salt resistant bacteria was lower than that of non-immobilization beads. The uptake rate of sodium chloride was decreased according to elongation of curing time. Reusability of Ca-alginate beads was possible but according to reutilization, the salt uptake volume of beads was also decreased. The uptake volume of sodium chloride from Doengjang by Ca-alginate beads on time course(3, 6, 12, and 24 hour) was revealed 5g, 6g, 7g and 7g, respectively.

• Membrane Journal
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• v.28 no.1
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• pp.62-66
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• 2018

In this study the cleaning spherical beads with same density as water were fabricated. Bead moving velocity was measured with respect to the aeration rate and bead concentration in water reservoir. The permeation experiments for FR (filtration and relaxation) and SFCO (sinusoidal filtration continuous operation) modes were simultaneously carried out under the condition of 1 to 3% cleaning spherical bead concentration, 20 LMH and 500 mL/min aeration rate in the MLSS 8,000 mg/L activated sludge solution. The used membrane was the $90cm^2$ effective area and $0.4{\mu}m$ nominal pore size flat membrane. The TMP (transmembrane pressure) decreased as the bead concentration increased, and was shown most effective in FR mode with 2% bead concentration.

• Journal of Pharmaceutical Investigation
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• v.41 no.1
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• pp.51-57
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• 2011

The objective of this study was to enhance the utilitization of Ibuprofen (IBU) by introducing the fast-disintegrating tablet (FDT) form. Presently, IBU is being widely used as a tablet or syrup form. But in contrast to these two formulations, IBU as FDT is not only convenient but also increases the control over the time release of the drug, noted by using Alginate beads. This study was carried out with Sodium Alginate and IBU at the ratios of 1:0, 1:0.5, 1:1, and 1:2 in order to produce a series of beads with different ratios. During the drying process of the beads, talc was added in beads to compare the effects with and without the talc. The final product was scanned with SEM imaging to determine the difference in the surface of the beads. The parameters assessed were the diameter, content assay, dissolution test and effectiveness of time-release. Direct compression method was used to prepare FDT containing IBU bead. The properties of FDT, such as hardness, disintegration time, were investigated. The dissolution profiles of FDT were tested using KP dissolution apparatus 1 (basket method). The results suggest addition of talc and drying the beads made the surface smooth and less vulnerable to clutter into chunks. The size of beads was less than 300 ${\mu}m$ which did not create a sandy feeling in the mouth. Thus, the beads formulation model made the sustained release of the drug possible, the hardness of FDT (1.25~1.50 $Kg/cm^2$) was acceptable and all the values of dissolving period were less than 30 seconds. The dissolution profile of FDT was same as that of IBU bead. The efficient dissolution profile and low price of IBU bead containing Sodium Alginate, the FDT formulation prepared from IBU bead can save the expenses and can improve the convenience of application of this drug.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.16 no.5
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• pp.999-1008
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• 2012

Unlike the existing CMOS chip, ISB (Intelligent Silicon Bead) is new concept biochip equipped with optical communication and memory function. It uses the light for power of SoC CMOS and interface with external devices therefore it is possible to miniaturize a chip size and lower the cost. This paper introduces an input protocol and a design of the low power and the low area to transfer the power and the signal through a single optical signal applied from external reader device to bead chip at the same time. It is also verified through simulation and measurement. In addition, low-power PROM is designed for recording and storing ID of a chip and it is successful in obtaining the value of output according to the optical input. Through this study, a new type biochip development can be expected by solving high cost and a limit of miniaturizing a chip area problem of an existing RFID.

• Journal of the East Asian Society of Dietary Life
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• v.22 no.1
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• pp.88-94
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• 2012

Histamine is a kind of primary biogenic amine arising from the decarboxylation of the amino acid L-histidine. The toxicology of histamine and its occurrence and formation in foods are especially emphasized in fermented foods. In this study, the biosensor for detection of histamine with functionalized multi-walled carbon nanotubes (MWCNT) was developed. We also searched for an appropriate insoluble substrate to immobilize the enzyme. The developed biosensor showed a detection limit of $0.1{\mu}M$ hydrogen peroxide. The enzyme reactor was prepared with diamine oxidase immobilized on insoluble carriers including CNBr-activated sepharose 4B, calcium alginate, and controlled pore size glass beads. The coupling efficiency of CNBr-activated sepharose 4B, calcium alginate, and controlled pore size glass beads were 48.5%, 40.3%, and 51.0%, respectively. In addition, the response currents on histamine with each immobilized enzyme reactor prepared with CNBr-activated sepharose 4B, calcium alginate, and controlled pore size glass beads were 120 nA, 110 nA, and 140 nA at $100{\mu}M$ of histamine concentration, respectively. Therefore, it is suggested that controlled pore size glass beads are the best carriers for immobilizing diamine oxidase to detect histamine in this biosensor.

• Economic and Environmental Geology
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• v.46 no.3
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• pp.215-220
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• 2013

We estimated the hydraulic conductivity of the sediments using constant-head permeability tests and electrical resistivity measurements with Jumoonjin standard sand of a uniform size and glass beads of different grain sizes. In this study, we determined the variations of the porosity, the hydraulic conductivity, and the resistivity in case 1 (changing the packing of the Jumoonjin standard sand) and in case 2 (varying the size of the glass beads). The results of case 1 showed that the hydraulic conductivity decreased with an increase in the electrical resistivity. This occurred because the sand grain while packing became rhombohedral with the a decrease of both the pore size and porosity. The results of the case 2 showed that the hydraulic conductivity increased due to the increase in the pore size as caused by the increased glass bead size. In addition, the porosity decreased and the electrical resistivity increased. Therefore, the relationship between the hydraulic conductivity and the electrical resistivity is negatively proportional as regards the grain packing with a change from cubic to rhombohedral whereas this relationship is positively proportional to the increase in the grain size.