• Elastomers and Composites
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• v.39 no.2
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• pp.131-141
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• 2004

The recycling of waste XLPE(crosslinked polyethylene), which is a major source of scraps from high voltage power transmission cables, has been discussed. The waste XLPE scraps were ground into fine powder with various sizes from less than $100{\mu}m$ up to about $1000{\mu}m$ using two types of tailor-made pulverizers. The compounds were prepared in a modular intermeshing co-rotating twin screw extruder at various conditions such as different compositions, types and powder sizes of waste XLPE, screw configurations and various polymer matrices (LDPE, HDPE, PP, PS). The mechanical and rheological properties and the fracture surface or the compounds were investigated. It was found that an improved impact strength was obtained from the compound with white XLPE powder pulverized from the scraps without outer/inner semi-conductive layers. Generally, the impact strength increases with the content of XLPE but decreases with the size of XLPE. Especially for LDPE, the extrusion was possible up to 80 wt% loading of XLPE. Also, the impact strength increases with the number of kneading disc blocks in the given screw configurations. The melt viscosity of the compounds increases with increasing XLPE loading. However, the higher shear thinning behavior of the compounds at common shear rates implies proper processibility of the compounds. In addition, the impact strength for other polymer matrices used increases with XLPE and it is noticeable that the impact strength of PS/XLPE (80/20 wt%) compound was improved twice that of pure PS.

• Elastomers and Composites
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• v.44 no.3
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• pp.282-289
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• 2009

The pressure-sensitive adhesive(PSA) tapes are widely used as floor-sealing material in Korean constructive industry. However, the general PSA tapes can not seal the apertures completely. This is one of main reasons to cause imperfect finishing. In order to solve the problems, the asphalts were modified by FKM powder and SBS in this study. The physical properties of modified asphalts were examined by measuring the softening point, viscosity, tensile strength and adhesion strength of FKM and SBS modified asphalt. The softening point of SBS modified asphalt was increased greatly due to the formation of network structure in asphalt. Also, the change of adhesion strength of SBS modified asphalt with temperature was not so great comparing to those of pure asphalt and FKM modified asphalt. The best results of pressure-sensitive adhesion could be obtained by the SBS(linear) modified asphalt containing 6 wt.% of linear type SBS.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.30 no.3 s.47
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• pp.369-375
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• 2004

In this study, liquid crystalline (LC) is formed using Gemini surfactant (GS) type and moisturizing effect in vivo is measured. $3.0\;wt\%$ of sodium dicocoyl ethylene diamine (PEG)-15 sulfate (SCD-PEG-15S) is used as GS and $4.0\;wt\%$ of hydrogenated dimer acid esters (HDAE) as booster. For stabilizers, $2.0\;wt\%$ of behenyl alcohol (BA) and $1.0\;wt\%$ of Iyso-lecithin (LyL) are utilized. It is stabilized in pH from 4.0 to 10.5 and the best condition is in pH 6.5. The value of viscosity is $8,000\pm500$ cP. The most excellent particles are formed within the range of 4.0 to 15.5 um. Formed LC is observed around LC particles using polarization microscope. It is also observed that lamellar gel network structure is formed around LC particles. Moisturizing effect is improved by $13.6\%$ (P<0.05) compared to control when measured 30 min later after coating samples. After 1 h, moisturizing effect is improved by 1$12.6\%$ (P<0.05) than control while showing $28.3\%$ (P<0.05) of improvement after 4 h. These results may be caused from that manufactured LC forms lamellar structure so that it has better water-holding ability and absorbance of oil increases. This formula could be utilized by delivery system (DS) on skin so that this technology can be applied for manufactuing pharmaceuticals and cosmetics.

• Food Science and Preservation
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• v.9 no.4
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• pp.418-424
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• 2002

This study was undertaken to develop the optimum baking formular and process in making the improved soy-wheat composite breads furtified with soy flour, which has been known for a source of biologically active phytochemicals and for more vegetable proteins as well. The effects of the addition of soy flour on a rheological properties of dough, on the sensory characteristics of breads, and on the possibilities of commercialization of these functional breads were investigated. As the added amount of soy flour increased, water absorption, development time and the weakness value of dough were increased, but dough stability were decreased in the farinograph. In the extensograph, the more soy flour was added, the less the extensibility and the resistance to extention were shown. As the amount of soy flour increased, gelatinazation point was increased in the amylograph, but the maxium viscosity was decreased. As the added amount of soy flour was increased, b value(yellowness) was obviously increased, L value(lightness) was slightly decreased. However, a value(redness) was not nearly changed in the color of cut loaves. In sensory evaluation, the more soy flour was added, the less the external, the internal characteristics and the eating qualities were shown. Accorting to the addition of soy flour, the toughness and the brittleness tended to be increased proportionally. The dough of 10% soy-wheat composite flour(SF10) was the most favorable on the baking performance.

• Food Science and Preservation
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• v.19 no.3
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• pp.344-353
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• 2012

This study was carried out to investigate the rheological properties of dough and the quality characteristics of breads with Saesalbori (non-waxy barley) and Saechalbori (waxy barley) flours added at concentrations of 10, 20, and 30% to wheat flour. The maximum viscosity increased in the Saesalbori flour mixtures and decreased in the Saechalbori flour mixtures. The dough stability of the 10% barley flour mixtures was equal to that of the control while that of the 30% barley flour mixtures decreased more. The extensibility of the dough decreased with the increasing level of barley flour in all the blends, but the resistance of the dough increased. As the ratio of barley flour increased, the loaf volume of the breads significantly decreased, but the bread weight increased. The 10% Saesalbori flour mixtures increased the hardness of the breads but did not cause any significant change in the other TPA parameters while the 10% Saechalbori flour mixtures did not cause any change in all the TPA parameters. The sensory evaluation results showed that the 10% barley flour mixtures had no significantly different overall acceptance from the control, and that the 20% substitution still resulted in acceptable sensory qualities. The results of the study also showed that the bread-making properties of Saesalbori were improved by germination, but those of Saechalbori declined.

• Food Science and Preservation
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• v.21 no.4
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• pp.491-499
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• 2014

Changes in various physicochemical and sensory characteristics of Samgyetang retorted at the $F_0$ values of 4.0 (F4), 7.0 (F7), and 10.0 (F10) were investigated during storage at $25^{\circ}C$ for 12 months. The pH level tended to decrease in all the treatments with the increase of the storage time, but no significant difference in the extent of the decrease was observed among the treatments. The values of volatile basic nitrogen, thiobarbituric reactive substances, and carbonyl contents increased rapidly over the storage period in the order of F4 > F7 > F10. The viscosity decreased most sharply between month 0 and month 2, after which the rate of increase declined. The oxygen concentration in the headspace of the retort pouch of the Samgyetang was higher for the samples retorted at higher $F_0$ values. In the sensory tests, the scores of the samples retorted at higher $F_0$ values tended to be lower, but all the characteristics of the samples, except for the texture of the T10 samples, were evaluated with scores higher than 5.0, the limit of marketability, over the storage time. In conclusion, the quality of the Samgyetang samples treated at higher $F_0$ values deteriorated more noticeably during storage.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.4 no.4
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• pp.208-218
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• 1992

Analytic solutions for the gradient of surface elevation and vertical profiles of velocity driven by the wind stress in the one-dimensional rectangular basin were obtained under the assumption of steady-state. The approach treats the bottom frictional stress $\tau$$_{b}$ as known and includes vertically varying eddy viscosity $textsc{k}$$_{M}$, which is constant, linear and quadratic of water depth. When the $\tau$$_{b}$ is param-terized with surface stress, depth averaged velocity and bottom velocity, the result shows the relation of the no-slip bottom velocity condition and the bottom frictional stress $\tau$$_{b}$. The results of a mode splitted, (x-$\sigma$) coordinate, numerical model were compared with the derived analytic solutions. The comparison was made for the case such that $textsc{k}$$_{M}$ is the constant, linear and quadratic function of water depth. In the case of constant $textsc{k}$$_{M}$, the gradient of surface elevation and vertical profiles of velocity are discussed for a uniform depth, a mild slope and a relatively steep slope. When $textsc{k}$$_{M}$ is a linear and quadratic function of water depth, the vertical structures of velocities are discussed for various $\tau$$_{b}$. The result of the comparison shows that the vertical structure of velocities depends not only on the value of $textsc{k}$$_{M}$ but also on the profile of $textsc{k}$$_{M}$ and bottom stress $\tau$$_{b}$. Model results were in a good agreement with the analytic solutions considered in this study.his study.y.his study.

• Korean Journal of Agricultural Science
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• v.22 no.1
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• pp.103-109
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• 1995

The model foods were prepared by simulating mositure, protein and starch, and they were heated for 30 mins, at $80^{\circ}C$ and then cooled at $25^{\circ}C$ in water bath. Their rheological properties were investigated by the use of Brookfield wide-gap rotational viscometer at $30{\sim}60^{\circ}C$, and the rotation speed ranged from 0.6 to 6 rpm and solid content ranged from 8% to 11%, the results obtained were as follows. 1. All the model foods ($P_1S_3$, $P_2S_2$, $P_1S_1$, $P_2S_1$, $P_3S_1$, $P_4S_0$) exhibited pseudoplastic behaviors with yeild stress and were thixotropic foods which showed time - dependent structural decays, but the starch food of 8 ~ 11 % solid content did not show the flow behavior. 2. The correlation between the rheological parameters and the protein content of model foods in various moisture content did not appeared a constant relationship. 3. The change of shear stress against shear rate in high starch foods was larger than that in high protein foods and the structure at initial shear time was decayed with a quatic equation according to the Tiu's Model and structural decay was in parallel with the increase of shear rate. 4. The temperature dependency of the apparent viscosity of $P_1S_2$, and $P_2S_1$ was fully expressed by Arrhenius equation and activation energies of their food were 2.35 and $1.34Kcal/g{\cdot}mol$, respectively.

• Culinary science and hospitality research
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• v.16 no.4
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• pp.247-259
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• 2010

In order to apply oriental medicine materials, which are applicable to the LOHAS concept demanded recently in society, to sauces, this study added different amounts of Omija, which has been proved to have various efficacies, effects and functions, to Bulgogi sauce with soy sauce as its main ingredient and analyzed the functionality of the prepared sauce through physical and sensory tests. General component analysis showed that, with increase in the Omija content, water content, crude ash and crude protein decreased, and crude fat was not detected As to color, L-value gradually increased with Omija content increased, and a-value indicating redness also increased as Omija extract added increased The higher the Omija content was, the lower pH and salinity were and the higher viscosity was. In the quantitative descriptive analysis of Omija Bulgogi sauce, with increase in the Omija content, color, flavor, taste and aftertaste grew stronger, and in the results of palatability test, the sauce containing Omija 5% was preferred most in all the evaluated items. In the quantitative descriptive analysis of Omija Bulgogi, with increase in the amount of Onija extract added, the strength of color, the flavor of sauce, and the taste of Omija grew stronger and the unpleasant smell, saltiness, sweetness and unpleasant taste grew weaker. Summing up the result of this study, when we tested five specimens of different Omija contents including a control, the specimen of 5% content was preferred most This result suggests that other kinds of fruit juice may be usable in soy sauce Bulgogi sauce and continuous efforts should be made to develop new types of Bulgogi sauce.

• Culinary science and hospitality research
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• v.19 no.5
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• pp.23-35
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• 2013

This study aimed to determine the physicochemical and sensory qualities of yogurt dressing prepared with Bokbunja juice(0, 10, 20, 30 and 40%). As the amount of added Bokbunja juice increased, contents of organic acids(citric acid, tartaric acid, malic acid, succinic acid and acetic acid) increased. The viscosity of the control group(8306.67 cP) was higher than those of the others(1633.33~6913.33 cP). The pH of the control group(3.96) was higher than those of the others(3.90~3.85). The sweetness of the control group(14.43) was lower than 10% Bokbunja juice added group(14.93). Color L decreased significantly, whereas a value and b value increased significantly with more Bokbunja juice added. DPPH radical scavenging activity of the control group was 5.84%, whereas those of yogurt dressing samples with Bokbunja juice ranged from 39.72~88.17%. The sensory property results showed that yogurt dressing with 30% Bokbunja juice added group had the highest value in terms of color, flavor, taste, mouth feel, and overall acceptability. Overall, the result of this study indicates that the yogurt dressing containing 30% of Bokbunja juice was most preferred among the groups.