• Polymer(Korea)
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• v.24 no.6
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• pp.869-876
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• 2000

In order to improve the cell-compatability of poly(L-lactide-co-glycolide) (75 : 25 by mole ratio of lactide to glycolide, PLGA) surfaces, the physicochemical treatments have been demonstrated. Chemical treatments were 70% perchloric acid. 50% sulfuric acid and 0.5 N sodium hydroxide solution and physical methods were corona and plasma treatment. The water contact angle of surface treated PLGA decreased from 73$^{\circ}$ to 50~60$^{\circ}$, i.e., increased hydrophilicity, due to the introduction of oxygen-containing functional group onto PLGA backbone by the measurement of an electron spectroscopy for chemical analysis. It could be observed that the adhesion and growth of fibroblast cell on physicochemically treated PLGA surfaces, especially perchloric acid treated PLGA surface, were more active than on the controt. In conclusion, it seems that surface wettability as hydrophilicity of PLGA plays an important role in cell adhesion, spreading and growth.

• Korean Chemical Engineering Research
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• v.45 no.5
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• pp.493-499
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• 2007

Polymeric hydrogel particles were fabricated to demonstrate the scale-up possibilities with the Particle Replication In Non-wetting Templates (PRINT) process. A permanently etched, specifically designed master was made on a silicon wafer using conventional photolithography, then reactive ion etching. The master and substrate were used repeatedly to make a large number of identical elastomeric perfluoropolyethers (PFPE) replica molds. The PFPE replica molds were used to fabricate and harvest individual, monodisperse micron-sized particles using the PRINT process. A water-soluble polymer adhesive was used as a sacrificial layer for harvesting particles. Particles were composed of biodegradable poly (ethylene glycol) diacrylate (PEG-diA), and aminoethylacrylate (AEM) and 2-acryloxyethyltrimethyl ammonium chloride (AETMAC) were added to them for improving the uptake of the cells. This study suggested PRINT used to produce the uniformed and shape specific biodegradable polymer is the effective technique for the non viral vector for the drug and the gene delivery.

• Journal of the East Asian Society of Dietary Life
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• v.13 no.2
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• pp.130-135
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• 2003

The Characteristics of dough and the quality of baguette with 1~5% pigmented rice(PR) were investigated. The pH of dough with PR were lower(pH 4.93~5.06) than that of the control(pH 5.13). The viscosity of dough with PR(498~575 BU) measured by the amylograph were lower than that of the control(600 BU). The volume of the baguette with PR(1~3%) was higher than that of the control. Color $L^{*}$ value of baguette crumb with PR decreased from 60.65 to 50.44~60.36 and color $a^{*}$ value increased from -2.13 to 0.28~3.30 as the concentration of PR increased. The hardness of the baguette decreased from 375.51$\times$10$^4$dyne/c $m^2$to 273.95~256.83$\times$10$^4$dyne/c $m^2$as the concentration of PR increased. The overall acceptability score of baguette was the highest with 3% PR.R.R.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.7
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• pp.908-911
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• 2006

Fish paste containing Styela clava (Korean name: miduduk) was prepared for the supplementary value of the product, and it was evaluated for the color, textural properities, and sensory attributes. Increasing the amount of S. clava in the fish paste tended to increase the lightness (L), the redness (a), and the yellowness (b) in Hunter color values. All test samples with 3 mm thickness had good flexibility and did not break even after 4 times folds. Fish paste containing 20% S. clava showed the highest values in strength, hardness, and adhesiveness. In overall acceptance of sensory evaluation, fish paste containing 5% S. clava did not show any difference in comparison with non added control. These results suggest that S. clava can be applied to fish paste products to improve the quality and functionality.

• Journal of the Korean Society of Food Culture
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• v.22 no.3
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• pp.330-335
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• 2007

This study was conducted to investigate the mechanical and sensory characteristics of aloe Suffitteok prepared with the different ratio of aloe sap for 4 days. Moisture content of Sulgitteok without aloe vera sap was 33.79%, and that of Sulgitteok prepared with 12% aloe vera sap decreased. As the storage time of Sulgitteok increased, moisture content reduced. The cohesiveness, springiness, adhesiveness, gumminess and chewiness of Sulgitteok decreased as aloe vera sap increased. The L values of aloe Sulgitteok significantly decreased with increasing aloe vera sap. The a value of Sulgitteok without aioe vera sap was -0.56, but showed negative value as aloe vela sap increased. The more aloe sap added, the higher b values rose. The overall acceptability of color, flavor, taste, softness and moistness in sensory evaluation showed that Sulgitteok prepared with 9% aloe vera sap had the highest score.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.35 no.3
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• pp.599-606
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• 2015

Damage of landslide due to earthquake covers a considerable part of total damage due to earthquake. Landslide due to earthquake affects direct damage of human lives and structures, and social system can be paralyzed by losing functions of roads, basic industries, and so on. Therefore, systematic and specialized research examining the factors affecting the slope stability by earthquakes should be needed. However, method of evaluation of slope stability problems due to earthquake contains somewhat uncertainty since many soil properties are predicted or assumed. In this study, influences of change of soil properties such as degree of saturation and cohesion value are analyzed in factor of safety and displacement using seismic landslide hazard maps based on GIS. As the degree of saturation increases or cohesion decreases, it is found that seismic landslide hazard area marked with factors of safety or displacements tends to increase. Therefore, to draw more exact landslide hazard map during earthquake, it is necessary to obtain accurate soil property information preferentially from site investigation data in the field.

• Korean journal of applied entomology
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• v.54 no.4
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• pp.289-294
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• 2015

Striped flea beetle, Phyllotreta striolata (SFB) and turnip sawfly, Athalia rosae ruficornis (TSF) are two economically important sporadic pests in radish fields on Jeju island. The response of adult SFB and TSF to a mixture of aggregation pheromone, (+)-(6R,7S)-himachala-9,11-diene and host plant volatile, allyl isothiocyanate (HAI), as well as to yellow and blue sticky traps was examined in radish fields. Adult SFB was more attracted to the sticky trap with HAI, regardless of the color of the sticky trap; however, adult TSF was more attracted on the yellow sticky trap than blue, and no effect of HAI was observed. The adult SFB and TSF can be effectively monitored using yellow sticky traps placed 10 cm above the plant canopy. SFB and TSF had 3 and 5 peak times in a year, respectively. The first peak occurred in the middle of March for SFB and mid-late of April for TSF. We expect that the results of the present study can facilitate minimizing the damage caused by the two important pests in commercial radish fields.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.41 no.2
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• pp.26-33
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• 2009

A new testing method to evaluate the deposition potential of white pitch was developed. The new method involves depositing the potential white pitch particles on the air bubble covered plastic film in the pitch deposit tester (PDT) developed by KRICT and analysing the deposited area of white pitch using an image analyzer. In addition, the effect of two important factors (pH and calcium hardness) on white pitch deposition potential was elucidated. When pH of the coated broke stock was increased from neutral to alkali or the calcium hardness of the stock was decreased, the pitch deposit area was decreased, implying that these two factors have to be controlled during the evaluation of pitch deposition potential. It was found that hydrophobicity of the surface of latex binding films repulped is a key factor influencing white pitch deposition.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.44 no.6
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• pp.43-49
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• 2012

In this work, the non-ionic polyethylene oxide(PEO)/phenolic formaldehyde resin(PFR) retention system, which was less affected by furnish charge, was analyzed for possibility and effectiveness when using recycled stock. When the micropolymer was added at the PEO/PFR retention system and the PAM/bentonite retention system, performance of retention and drainage was improved. When the cationic micropolymer was added on the PEO/PFR retention system, the highest retention was achieved. The Polyacrylamide(PAM)/bentonite system induced flocculation of white pitch by electrostatic flocculation. On the other hand, the non-ionic PEO/PFR retention system induced less flocculation of white pitch than the PAM/bentonite retention system.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2003.10a
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• pp.250-253
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• 2003

This paper concerns about an experimental investigation about steering performance of tracked vehicle on extremely soft soil based on DOE(Design Of Experiment) using L8 orthogonal Array. A tracked vehicle model with principal dimensions of $0.9m{\times}0.8m{\times}0.4m$ and weight 167kg was constructed with a pair of driving chain links driven by two AC-servo motors. The tracks are configured with detachable grousers, the span of which can be varied. Deep seabed was simulated by means of bentonite-water mixture in a soil bin of $6.0m{\times}3.7m{\times}0.7m$. Turning radii of vehicle and torques of motors were measured with respect to experimental variables; steering ratio, driving speed, grouser chevron angle, grouser span, grouser height. The effects of experiment variables on steering performance are evaluated.