• Journal of the Korean Society of Food Science and Nutrition
• /
• v.41 no.2
• /
• pp.182-191
• /
• 2012

Black rice bran powder has potential medical uses and functionality. In this study, we assessed the antioxidant activity and quality characteristics of cookies containing various concentrations (0, 1, 3, 5, 7, and 9%) of black rice bran powder. To analyze quality characteristics, proximate composition, fatty acid composition, amino acid composition, bulk density and pH of the dough, spread factor, loss rate, leavening rate, color, texture profile analysis, and sensory evaluations were measured. Black rice bran cookies (7%) contained more crude protein ($10.67{\pm}0.33$%) compared to control ($5.84{\pm}0.06$%). The total unsaturated fatty acid contents of the control and 7% black rice bran cookies were 30.44 and 30.81%, respectively. The amino acid content of 7% black rice bran cookie was higher than that of control. Bulk density of the dough, moisture, spread factor, total polyphenol content, and DPPH free radical scavenging activity of the cookies significantly increased with increasing content of black rice bran powder, whereas pH of the dough, loss rate, leavening rate, and L values of the cookies decreased. Additionally, consumer acceptability scores for the 7% black rice bran cookie group ranked significantly higher than those of the other groups in terms of appearance, taste, flavor, texture, and overall preference. Taken together, the results of this study suggest that black rice bran powder is an effective ingredient for increasing the consumer acceptability and functionality of cookies.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.20 no.1
• /
• pp.31-34
• /
• 2007

In this study, in order to develop multilayer ceramics vibrator for ultrasonic nozzle, PMN-PNN-PZT ceramics were fabricated using $Li_{2}CO_{3}-Na_{2}_CO_{3}$ as sintering aids and their piezoelectric and dielectric characteristics were investigated according to the amount of PbO. With increasing PbO contents, secondary phases were increased and phase structure was changed from tetragonal structure to rhombohedral structure and also electromechanical coupling factor was linearly decreased. At the composition ceramics with the sintering temperature of $870^{\circ}C$ and 1 mol% excess PbO, density, electromechanical coupling factor, dielectric constant, piezoelectric d constant and mechanical quality factor showed the optimum value of $7.879\;g/cm^{3}$, 0.55, 1149, 328 pC/N, 1224, respectively for multilayer ceramics vibrator application for ultrasonic nozzle.

• The Transactions of the Korean Institute of Electrical Engineers C
• /
• v.49 no.3
• /
• pp.155-160
• /
• 2000

The piezoelectric properties and the doping effect for$0.95Pb(Zr_xTi_{1-x})O_3+0.05Pb(Mn1/3Nb2/3)O_3$ compositions were studied. Also, the heat generation and the change of electromechanical characteristics, the important problem in practical usage, were investigated under high electric field driving. As a experiment results under low electric field, the values of kp and $\varepsilon33T$ were maximized, but Qm was minimized(Kp=0.57, Qm=1550) in the composition of x=0.51. In order to increase the values of Qm $Nb_2O_5$ was used as a dopant. As the result of that, the grain size was suppressed and the uniformity of grain was improved. Also, the values of kp decreased, and the values of Qm increased with doping concentration of $Nb_2O_5$. As a experiment results under high electric field driving, when vibration velocity was lower than 0.6[m/s], the temperature increase was $20[^{\circ}C]$, and the change ratio of mechanical quality factor was less than 10[%]. So, its electromechanical characteristics was very stable. Conclusively, piezoelectric ceramic composition investigated at this paper is suitable for application to high power piezoelectric devices.

• Proceedings of the KWS Conference
• /
• 2002.10a
• /
• pp.551-554
• /
• 2002

As a general rule, the brazing process between cemented carbides and steel used by Silver (Ag) type brazing filler. The composition of Ag type filler were used Ag-Cu-Zn-Cd type filler mainly. But, the demand of Cadmium (Cd)-free in Ag type filler was raised recently. The reason why Cd-free in Ag brazing filler were occupied to vaporize as a CdO$_2$ when brazing process, because of Cd element was almost low boiling point of all Ag type filler elements. And, CdO$_2$ was a very harmful element for the human body. This experiment was developed Cd-freeing on Ag type filler that was used Indium (In) instead of Cd element. In this experiment, there were changed from 0 to 5% In addition in Ag brazing filler and investigated to most effective percentage of Indium. As a result, the change of In addition instead of Cd, there was a very useful element and obtained same property only 3% In added specimens compared to Cd 19% added specimens. These specimens were obtained same or more deflective strength. In this case, there were obtained 70 MPa over strength and wide brazing temperature range 650-800 C. A factor of deflective strength were influenced by composition and the shape of $\beta$ phase and between $\beta$ phase and cemented carbides interface. Indium element presented as $\alpha$ phase and non-effective factor directly, but it's occupied to solid solution hardening as a phase. $\beta$ phase were composed 84-94% Cu-Ni-Zn elements mainly. Especially, the presence of Ni element in interface was a very important factor. Influence of condensed Ni element in interface layer was increased the ductility and strength of brazing layer. Therefore, these 3% In added Ag type filler were caused to obtain a high brazing strength.

• Bulletin of the Korean Chemical Society
• /
• v.24 no.3
• /
• pp.363-368
• /
• 2003

The major ionic components of precipitation collected at the 1100 Site of Mt. Halla and Jeju city have been determined. The reliability of the analytical data was verified by the comparison of ion balances, electric conductivities and acid fractions; all of their correlation coefficients were above 0.94. Ionic strengths lower than $10^{-4}$ M were found in 53% of the 1100 Site samples and 28% of the Jeju city samples. Compared with other inland areas, the wet deposition of $Na^+,\;Cl^-\;and\;Mg^{2+}$ was relatively larger, but that of $NH_4^+,\;nss-SO_4^{2-}$(non-sea salt sulfate) and $NO_3^-$ was lower. Especially the wet deposition increase of $Ca^{2+}$ in the spring season supports the possibility of the Asian Dust effect. The acidification of precipitation was caused mostly by $SO_4^{2-}\;and\;NO_3^-$ in the Jeju area, and the organic acids have contributed only about 7% to the acidity. The neutralization factors by NH₃were 0.47 and 0.48, and that of CaCO₃was 0.31 and 0.25 at the 1100 Site and Jeju city, respectively. Investigation into major influencing sources on precipitation components by factor analysis showed that the precipitation at the 1100 Site had been influenced mostly by an anthropogenic source, followed by soil and seawater sources. The precipitation at Jeju city was mainly influenced by oceanic sources, followed by anthropogenic and soil sources.

• Journal of Korean Society of Water and Wastewater
• /
• v.36 no.5
• /
• pp.261-273
• /
• 2022

In this study, we collect water control valves that have had accidents due to existing cracks, etc. are collected, and propose investigation items for strengthening the valve structural safety evaluation through a series of analyzes from valve specifications to physicochemical properties are proposed. The results of this study are as follows. First, there was a large variation in the thickness of the body or flange of the valves to be investigated, which is considered to be very important factor, because it may affect the safety of the valve body against internal pressure and the flange connected with the bolt nut. Second, 60% of the valves under investigation had many voids in the valve body and flange, etc. and the decrease in thickness due to corrosion was relatively large on the inner surface in contact with water rather than the outer surface. It is judged that the investigation of depth included voids is very important factor. Third, all valves to be investigated are made of gray cast iron foam, and therefore it is judged that there is no major problem in chemical composition. It is judged that the chemical composition should be investigated. Fourth, as a physical investigation item, the analysis of metal morphology structure seems to be a very important factor for nodular cast iron from rather than a gray cast iron foam water valve with a flake structure. As it was found to be 46.7~68.8% of the standard recommended by KS, it could have a direct effect on damage such as cracks, and therefore it is judged that the evaluation of tensile strength is very important in evaluating the safety of the valve.

• Proceedings of the KIEE Conference
• /
• 1999.07d
• /
• pp.1723-1725
• /
• 1999

This paper is the study for piezoelectric properties of PMN-PT-PZ composition for high power piezoelectric device. It needs the properties such as high mechanical quality factor(Qm), high electromechanical coupling coefficient(kp) and high dielectric strain constant$(d_31)$, and the stable electromechanical properties under high vibration level. For acquiring this results, the value of x is changed in 0.1Pb$(Mn_{1/3}Nb_{2/3})O_3$+(0.9-x)$PbZrO_3+xPbTiO_3$ composition to find MPB(morphotropic phase boundary), and the piezoelectric constants is measured by resonance-antiresonance frequency method, based on IRE Standard. Also, it is measured as a function of the amount of additive, $Nb_2O_5$. When the composition is applied to high power device, the electromechanical properties is measured by laser vibrometer to confirm the reliablity under high vibration level. From these results, PMN-PT-PZ composition is shown excellent properties and capacity of application to high power device.

• Asian-Australasian Journal of Animal Sciences
• /
• v.22 no.10
• /
• pp.1414-1419
• /
• 2009

The study was conducted to evaluate the effects of trivalent chromium from different sources on growth, carcass composition, and serum parameters in finishing pigs. Ninety-six crossbred pigs with an initial average body weight of 65.57${\pm}$1.05 kg were blocked by body weight and randomly assigned to four treatments with three replicates. Pigs were offered one of four diets including a control diet or the control diet supplemented with 200 ${\mu}g/kg$ chromium from either chromium chloride ($CrCl_{3}$), chromium picolinate (CrPic) or chromium nanocomposite (CrNano) for 40 days. After completion of the feeding trial, eight pigs from each treatment were selected to collect blood samples, and slaughtered to measure carcass composition. The results showed that supplemental chromium had no significant effect on growth performance, while CrNano increased carcass lean proportion and loin Longissimus muscle area (p<0.05), and decreased carcass fat proportion and 10th rib backfat depth (p<0.05). CrPic supplementation also resulted in lower fat proportion and larger Longissimus muscle area (p<0.05). The addition of Cr from CrNano or CrPic decreased serum glucose (p<0.05) and increased concentrations of total protein and free fat acid in serum (p<0.05). Serum urea nitrogen, triglyceride and cholesterol were decreased (p<0.05), and serum high density lipoprotein and lipase activity were increased (p<0.05) with the supplementation of CrNano. Serum insulin was decreased (p<0.05) by supplemental Cr from CrNano or CrPic, and serum insulin-like growth factor I was increased significantly in the CrNano treated group. These results suggest that chromium nanocomposite has higher efficacy on carcass composition in pigs compared to the traditional chromium sources.

• Journal of the Korean Institute of Educational Facilities
• /
• v.18 no.6
• /
• pp.33-43
• /
• 2011

The Korean academics of classical learning, Seowon which from the middle of Joseon Dynasty was complexly reflected in "the illustration of Taiji(太極圖說)" Five-Elements school(陰陽五行說), "Zhou Yi(周易)" and a theory on spherical heaven and square ground(天圓地方) which based on orientalism. Also the theory of Xiangshu Xue(象數學) was a significant factor to decide the size(number of facade module) of Seowon architecture. So, in this study, how the oriental thought was adopted and reflected in existing 21 Seowon in South Korea. The size of Seowon architecture was adopted a theory of combination with heaven, earth and human(天地人三合論) that based on the theory of Xiangshu Xue on "the illustration of Taiji" and "Zhou Yi". "Zhou Yi" was the central thought of Confucian culture in Joseon Dynasty, with which Seowon space was divided into two, ancestral rites space and lecture space. It coincides with balance of yin(陰) and yang(陽), Five-Elements(五行) and four seasons(四季節). In lecture space, lecture hall is relevant with the water(水) and winter, and front tower structure or outer three-door is the fire(火) and summer. Also, central garden means the soil(土) and center. Thus, the size and spatial composition was planned with the philosophy, "the illustration of Taiji", Five-Elements school and a theory on spherical heaven and square ground. Yin and yang has an idea of the heaven and earth, and Five-Elements has an idea of direction and season with which spatial composition of Seowon could be set. And the numeral meaning on the theory of Xiangshu Xue established an ideal background for spatial composition of Seowon architecture.

• Korean Journal of Community Nutrition
• /
• v.7 no.1
• /
• pp.102-110
• /
• 2002

Cigarette smoking has long been recognized as a major risk factor in the development of coronary heart disease. Several investigators have reported the strong association between smoking and high serum cholesterol, triglyceride concentration, SFA and low HDL cholesterol, PUFA and $\omega$6 concentrations. Therefore, this study was done to investigate the effect of smoking on the serum lipid profile and fatty acid composition of college women. Sixty-one non-smokers and twenty-seven smokers were selected from college women students in the Seoul area. Their lipid intake, serum lipid concentration and fatty acid composition were examined. There were no differences in the general characteristics and anthropometric indices between the smokers and non-smokers. However, alcohol consumption was significantly higher in smokers than non-smokers (p<0.001). The daily caloric intake of smokers and non-smokers were 1875.84 kcal and 1915.53 kacl, respectively. On the other hand, the mean daily intake of lipids and cholesterol were significantly lower in smokers (p<0.05). In smokers, the mean concentrations of serum total cholesterol, LDL-cholesterol and the LDL-C/HDL-C ratio were higher, and the compositions of EPA and DHA were lowe than in non-smokers. There was a negative correlation between the serum triglyceride and PUFA levels in the two groups. Also, serum HDL-C correlated negatively with MUFA in smokers and non-smokers (p<0.01). These results suggest that smoking cause inadequate changes in serum lipid profile and serum fatty acid composition, thereby increasing the tendency for coronary heart disease.