• Resources Recycling
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• v.21 no.2
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• pp.34-40
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• 2012

$Pt_{10}$/C, $Pt_9Mn_1$/C, $Pt_7Mn_3$/C electrocatalysts for Polymer Electrolyte Membrane Fuel Cells(PEMFCs) were synthesized by reduction with HCHO and their activity as a oxygen reduction reaction(ORR) was examined at half cell. The electrochemical oxygen reduction reaction(ORR) was studied by using a glaasy carbon electrode through cyclic voltammetric curves(CV) in a 1 M $H_2SO_4$ solution. The ORR activities of $Pt_9Mn_1$/C were higher than $Pt_{10}$/C, $Pt_7Mn_3$/C. Also potential-current curves of $Pt_9Mn_1$/C at 0.9, 0.8, 0.7, 0.6V for 5minutes respectively were higher than $Pt_{10}$/C, $Pt_7Mn_3$/C. Physical characterization was made by using x-ray diffraction(XRD) and transmission electron microscope(TEM). The TEM images of $Pt_9Mn_1$/C, $Pt_{10}$/C catalysts showed homogenous particle distribution with particle size of about 2.7 nm, 3 nm respectively and then the XRD results showed that the crystalline structure of the synthesized catalysts are seen FCC structure.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.6
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• pp.847-853
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• 2015

The purpose of this study was to compare color, protease, and antioxidant activities of Korean traditional soy sauce fermented for 120 days in Onggis obtained from five regions-Gangjin, Jeju, Ulsan, Yeoju, and Yesan in Korea. The brown color of soy sauce was increased during the fermentation period and was the highest in soy sauce fermented in Yesan. The values of total phenol contents, protease activity, and ferric reducing antioxidant power (FRAP) and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity activities were also increased during the fermentation period of soy sauce. Soy sauce fermented in Gangjin Onggi showed the highest protease activity, total phenol contents, DPPH radical scavenging activity, and FRAP ability. The partial least squares regression analysis indicated that the regional Onggis affect the quality of soy sauce with in terms of color, protease activity, and antioxidant activity.

• Journal of Ocean Engineering and Technology
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• v.27 no.5
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• pp.99-104
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• 2013

Recently, various nanoparticles have been used for filler in polymer matrices. The particles of nano size are whether high or not cross-link density in polymer affects the thermal and mechanical properties of one. The properties change as a result of chemical reactions between the nanoparticles and the surface of the polymer. There are two models for nanocomposites: "repulsive interaction" and "attractive interaction" between the nanoparticles and matrix. In this study, the variation in the curing mechanism was examined when nano-size $TiO_2$ was dispersed into an epoxy (Bisphenol A, YD-128) with different curing agents. The results of this study showed that the exothermic temperature and Tg in the case of the nanoparticles used (Jeffamine) (D-180) at room temperature were reduced by an increase in the $TiO_2$ contents because of the "repulsive interaction" between the nanoparticles and the matrix. The tensile strengths were increased by increasing amounts of $TiO_2$ until 3 wt% because of a dispersion strengthening effect caused by the nanoparticles, because of the repulsive interaction. However, such tensile properties decreased at 5 wt% of $TiO_2$, because the $TiO_2$ was agglomerated in the epoxy. In contrast, in the case of the nanoparticles that used NMA and BDMA, the exothermic temperature and Tg tended to rise with increasing amounts of $TiO_2$ as a result of the "attractive interaction." This was because the same amounts of $TiO_2$ were well dispersed in the epoxy. The tensile strength decreased with an increase in the $TiO_2$ contents. In the general attractive interaction model, however, the cross-link density was higher, and tensile strength tended to increase. Therefore, for the nanoparticles that used NMA, it was difficult to conclude that the result was caused by the "attractive model."

• Journal of Korean Tunnelling and Underground Space Association
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• v.22 no.3
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• pp.277-291
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• 2020

Shield TBM is a tunnelling method that has a wider range of applications in the poor ground condition compared to conventional tunnels (Drill and Blast). Currently, a 13.3 m large-diameter slurry shield TBM is preparing for construction to pass under the Han River. Shield TBM is divided into slurry and EPB shield TBM, and management items during construction are different depending on each characteristic. In this paper, the equipment type, origin, application case and trouble case were analyzed for slurry shield TBM, which is mainly constructed in soft ground. In addition, 2D and 3D model tests were conducted on the condition of soil depth for the possibility of slurry leakage into front of the equipment, with appropriate chamber pressure. Based on this paper, it proposed to provide basic and reference data for proper excavation surface pressure and chamber pressure during construction of slurry shield TBM under soft ground conditions, and proposed measures to minimize stability and environmental decline due to slurry ejection.

• Journal of agriculture & life science
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• v.45 no.6
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• pp.135-140
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• 2011

This study was conducted to determine the effect of grape by-product on milk yield, milk composition and blood metabolites of lactating cows. A total of 8 Holstein dairy cows (average age = 89.9 months, average lactation day = 164.4, Reproduction number = 2.8) were randomly allocated into control (no additives, CON) or grape by-product treatment (add 1 kg of grape by-product per day, GBP) for 3 weeks. The concentrations of fat, protein, lactose and total solid in milk were not affected by grape by-product supplementation. However, milk yield (23.13 vs. 21.16 kg/d) was higher (p<0.05) in GBP than in CON, while SCC was lower (p<0.05). The concentrations of glucose, alanine aminotransferase, total protein and BUN in blood did not differ between treatments. But blood aspartate aminotransferase and total cholesterol concentrations (123.75 vs. 95.34 IU/L, 200.82 vs. 180.63 mg/dl) were higher (p<0.05) in cows fed GBP than CON. As the result, grape by-product, which has a various potential benefits, could be used as a functional diet supplement for lactating dairy cows.

• Korean Journal of Comparative Education
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• v.26 no.4
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• pp.55-80
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• 2016

Kerala, a southern-west state of India, has been vigorously studied due to its unique development status. Indeed, Kerala shows such a high level of social development as Human Development Index indicates, yet it is suffering from the low level of economic. As a result, scholars have examined a broad range of rationales to understand the 'Kerala Development Model' as discussing historical contexts, social welfare policies, land reforms by Communist Party of India, and so on. Among them, scholars agree that education is one of the most critical factors that led to social development of Kerala. Despite the consensus, there has been lack of research that deeply look into how education has been delivered, what impacts it has on people, and why it contributes to social development in Kerala. This research, thus, would discuss the meanings, values and impacts of education with the capability approach that is originally termed by Amartya Sen. The approach criticize the dominant paradigm of 'development' that is materialistic oriented, instead it emphasizes expanding a range of capabilities of people to reach 'development' that people can act upon what they value and cherish. Based on Sen's perspective, we believe that dimensions of education can be re-defined and expanded in a relation to development.

• Elastomers and Composites
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• v.38 no.1
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• pp.57-64
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• 2003

Metal oxide(MgO) was added to FKM rubber in order to develop automotive fuel hose which ran show elastic characteristics under extreme condition. Cure characteristics, physical properties, thermal resistance and fuel resistance of FKM compounded rubber with MgO were investigated. MgO was mixed to FKM rubber materials within the range of $0{\sim}20phr$. From the test results of rheological properties and Mooney viscosity, the $t_{s2}$, $T_{c90}$ values increased as the MgO contents increased in FKM rubber compounding. Hardness and 100% modulus of FKM compounded rubber slightly increased, but tensile strength and elongations at break slightly decreased. From the test results of thermal resistance of rubber specimens at 130, 150, and $170^{\circ}C$ for 70 hrs, the changing rate of physical properties was found to be relatively small. Fuel resistance tests were carried out for fuel A, B, C and D at $40^{\circ}C$ for 70hrs, and the results showed that the changing rate in physical properties was found to increase from Fuel A to D, Furthermore thermal properties of FKM compounded rubber containing MgO were also investigated by using TGA/DSC. The optimum mixing ratio of additive to FKM rubber to get the maximum effect on thermal resistance and fuel resistance, within the range of desirable specification for rubber material, was determined to be 6 phr for MgO.

• The Journal of the Korea institute of electronic communication sciences
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• v.16 no.4
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• pp.591-598
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• 2021

The digital phase-locked loops(DPLL) is a circuit used for phase synchronization and has been generally used in various fields such as communication and circuit fields. State estimators are used to design digital phase-locked loops, and infinite impulse response state estimators such as the well-known Kalman filter have been used. In general, the performance of the infinite impulse response state estimator-based digital phase-locked loop is excellent, but a sudden performance degradation may occur in unexpected situations such as inaccuracy of initial value, model error, and disturbance. In this paper, we propose a minimum variance finite impulse response filter with optimal horizon for designing a new digital phase-locked loop. A numerical method is introduced to obtain the measured value interval length, which is an important parameter of the proposed finite impulse response filter, and to obtain a gain, the covariance matrix of the error is set as a cost function, and a linear matrix inequality is used to minimize it. In order to verify the superiority and robustness of the proposed digital phase-locked loop, a simulation was performed for comparison and analysis with the existing method in a situation where noise information was inaccurate.

• Korean Journal of Breeding Science
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• v.43 no.6
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• pp.587-590
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• 2011

A new sesame variety 'Yunheuk' was developed from Yeongnam Agricultural Research Institute in 2007. A cross was made by 'Yoosung' with weak disease resistance and 'Kunheuk' with high yield capacity & quality, followed by pedigree selection, yield test and regional yield trial (RYT) by the sesame breeding team at the National Institute of Crop Science and Yeongnam Agricultural Research Institute up to 2007. The variety showed higher lodging resistance and more dark seed coloring rather than that of check variety 'Yangheuk'. Average stem length and the number of capsules per plant is 118 cm, 79 cm respectively. Its 1,000 grains weight is about 2.67 g indicating 0.10 g lower than that of 'Yangheuk', and its oil content is about 46.4%. 'Yunheuk' also contains total 2.59 mg/g of such lignans as sesamin and sesamolin. And its dark color density ($L^*$ Value) of seed coat is 22.43 which was about 10% lower than that of check variety. The average yield of 'Yunheuk' was 99.9 kg per 10a at the national-wide regional performance.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.6
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• pp.370-378
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• 2019

The aim of this study was conducted to investigate the awareness and practice of personal hygiene and clinic hygiene of infection among physical therapist and to analyze the factors affecting it to provide basic data for the establishment of nosocomial infection management programs and policies in the physical therapist unit. In this study, 320 physical therapists were collected and analyzed. The study tool used a self-administered questionnaire to investigate general characteristics and awareness and practice of nosocomial infections. Responses were determined as 5-Likert scales and data were analysed using percentage, independent t-test, ANOVA. As a result of this study, 17.8% of infectious disease management departments were not found, and 41.6% of physical therapists were not educated about nosocomial infection. In addition, physical therapists with sufficient protective equipment for treatment were very low at 25.3%. Thus, in order to increase awareness and practice of nosocomial infection in the future, it is necessary to provide enough protective equipment for the treatment within the hospital, and it is considered that the nosocomial infection education of the physical therapist should be carried out regularly in the hospital itself.