• Proceedings of the Korea Concrete Institute Conference
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• 2006.05b
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• pp.41-44
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• 2006

Recently, single shell lining method of construction is studied by economical method of construction to make use of high-performance shotcrete of permanent shotcrete lining concept in the UStA, Europe, Japan etc. High-performance shotcrete use is essential as permanent support that single shell lining method of construction has two functions of lining and support to shotcrete. In this research, optimum accelerator amount was decided after setting time test using alkai-free and cement mineral accelerator. Also replacement ratio of silica fume and fly-ash was determined.

• International Journal of Aeronautical and Space Sciences
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• v.18 no.3
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• pp.588-600
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• 2017

We develop a wireless, contact free power transfer mechanism that is safer than the direct metallic contact and robust to imperfect alignment on landing at the base station. A magnetic field is created using inductors on both the transmitting and receiving sides. We use the inductive wireless recharging to increase autonomy and decrease the sensor interference by reducing the inductor loop size. By locating four independent small receiver loops and corresponding four circuits around the quadrotor UAV, we can increase safety from circuit malfunctions in comparison to the use of just one loop. On the base station, four folding robotic bars are used to realign the receiver loops over the transmitter loops. After adequate recharging as measured by battery voltages or power consumption at the bae station, the UAV sends a signal to the base station to open the robotic bars and takes off once freed from the robotic bars.

• Journal of Animal Reproduction and Biotechnology
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• v.34 no.4
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• pp.305-310
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• 2019

Embryos produced with serum show the alterations in their ultrastructure, impaired compaction, abnormal blastulation, aberrant mRNA expression profiles and large calf syndrome with greater incidences of stillbirths and deaths after birth. The aim of the present study was to describe in vitro embryo production by analyzing embryo production, fetal production and pregnancy rate in free-serum medium. The OPU-IVP data used in this study from 2016. Approximately, sixteen cows (Hanwoo), which belonged to the Institute of Gyeongsang National University, were used. Two experimental group is used in this study. Serum groups were conducted in March to July and free-serum group was conducted in September to December. The recovered cumulus-oocyte complexes were morphologically classified to four grades based on the compaction of cumulus cells layers and homogeneity of the cytoplasm. The number of oocyte was significantly greater in serum groups than that in free-serum groups (29.61 ± 0.63 vs. 15.6 ± 0.62; p < 0.05). Between serum and free-serum groups indicate that average of 1st and 2nd grade oocytes were no difference (2.38 ± 1.67 vs. 2.38 ± 1.48; p > 0.05), but number of 3rd and 4th grade oocytes were greater in serum groups than that in free-serum groups (7.31 ± 7.64 vs. 5.60 ± 6.29; p < 0.05). Embryo cleaved competence was higher in rate in free-serum groups than that in serum groups (62.1% vs. 58.3; p < 0.05). However, blastocyst developmental rate was no difference between serum and free-serum groups (33.1% vs. 43.5%; p < 0.05). 986 recipients were used for embryo transfer. Pregnancy rate was indicated that between serum and free-serum group was no difference (54.6% vs. 56.3%; p < 0.05). In conclusion, we developed the free-serum system for production of in vitro bovine embryos in order to meet the developmental and qualitative requirements for large scale commercial use.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.30 no.1
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• pp.7-17
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• 1998

With the advent of CLSM in the end of 1980s, it has been applied to the field of pulp and paper science in various ways. This study showed the potentials of CLSM In analyzing a change of pulp fiber and paper properties before and after mechanical treatment. In particular, a quantification of internal fibrillation has been done using cross-sectional images of fibers and image analysis technique, then evaluated the effects of fiber wall delamination on fiber and paper properties. It showed that the delaminated fibers were closely associated to development of the interfiber bonding in a fiber network. The CLSM made it possible to investigate a density profile along the sheet thickness, which was created by some papermaking processes like pressing, drying and calendering. Through the attempt to observe the forming procedure of a fiber network during handsheet making, the CLSM images showed that the pressing stage was considered greatly to contribute to generation of interfiber bonding with removing a free water and partly a bound water between fibers. In addition, the CLSM could be used to illustrate not only a surface profile of paper showing the extent of smoothness or roughness, but also a density profile in a B-direction of the network. Finally it became evident that the CLSM could be used as an excellent tool to predict development in fiber and paper properties before and after mechanical treatment during papermaking processes.

• Journal of Microbiology and Biotechnology
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• v.19 no.6
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• pp.604-609
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• 2009

To investigate the potential use of microbial heme as an iron source, recombinant Escherichia coli coexpressing ALA synthase (HemA) as well as the NADP-dependent malic enzyme (MaeB) and dicarboxylic acid transporter (DctA) were cultured. The typical red pigment extracted from the recombinant E. coli after 38 h showed highest absorbance at 407 nm, and the amount of iron in 38.4 mg of microbial heme extract derived from 6-1 fermentation broth was 4.1 mg. To determine the commercial potential of the recombinant E.coli-synthesized iron-associated heme as an iron source, mice were fed the iron-free provender with the microbial heme extract. The average body weight reduction of mice fed non-iron provender was 2.3%, whereas no detectable weight loss was evident in mice fed microbial heme addition after 15 days. The heme content of the blood from microbial heme fed mice was 4.2 mg/ml whereas that of controls was 2.4 mg/ml, which implies that the microbial heme could be available for use as an animal iron source.

• Proceedings of the SCSK Conference
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• 2003.09b
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• pp.524-526
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• 2003

Lipsticks are cosmetics which do not contain water and are usually preserved with parabens. When submitted to the Challenge Test, theses products did not reach the CTFA criteria, which means that microbiological contamination could occur before the end of its shelf life. The aim of this study was to evaluate the contamination level of 130 lipsticks after its use. Microorganisms were isolated from 14,6 % of the samples. However, only in two samples (1,5%) the contamination level exceeded the 100 CFU/g level, which means that, although the preservative system was not efficient to eliminate bacteria, the lack of free water was enough to prevent the microbial development. Total bacteria and fungi were determined by conventional methodology, according to CTFA Microbiological Guidelines. The microbes were then isolated and characterized as normal skin flora microorganisms. This suggest that products were contaminated by the constant application of lipsticks by consumers. This could lead to cross contamination when the same product is shared by several people. Extra care should be taken into account when this type of products are available to be tested by several consumers in demonstration displays.

• Food Science of Animal Resources
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• v.43 no.5
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• pp.889-900
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• 2023

In this study, concentration levels of beet powder (BP) and caramel color (CC) were optimized to simulate beef color in meat analogs before and after cooking. The central composite design of response surface methodology (RSM) was used to set the levels of BP and CC, and the CIE L^*, CIE a^*, and CIE b^* were selected as the responses for RSM. After optimization, myoglobin-free beef patties were prepared with three optimized levels of BP and CC. When raw, all the patties had the same color as natural beef; however, CIE L^*, CIE a^*, and CIE b^* were statistically different from those of beef after cooking (p<0.05). Moreover, the use of BP and CC induced "browning" after the cooking process, with no excessive yellow color. Therefore, based on the overall desirability in the color optimization using RSM, the combination of BP (1.32%) and CC (1.08%) with the highest overall desirability can be used to simulate the color change of beef in meat analogs.

• Journal of Family Resource Management and Policy Review
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• v.4 no.2
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• pp.57-73
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• 2000

The Purpose of this study is to scrutinize the time structure and time use pattern of North Korean and to identify the differences of time use patterns between South and North Korean Societies. To carry out this Purpose in-depth interviews with ten people who escaped from North Korea after 1990 and empirical survey with 158 subjects were conducted. The findings are as follows. The characteristics of time life of North Korean are uniform time use pattern in tightly scheduled daily life and shortage of disposable time and constraint of free time due to job related labor, extra job activities including learning, meeting and evaluation, and labor mobilization. Women are faced with heavy burden of doing job and housework in the continuing patriarchal way of thinking and in the circumstances of poor housing environment. In North, Leisure time is constraint and leisure facilities are poor and the concept of leisure is totally different as that of South. North Korean think leisure as connecting with work and education and as public sphere, not private sphere. I this context leisure is considered as means for the strengthening of the communist society. Differences in the perception of time life through defectors are as follows. In South, there are plenty of leisure time and man can control his own time. Man spend his free time for various activities, especially for cultural activities such as sports, recreation, eating out with families and spend time till late in the outdoors. This study revealed differences in many aspects of time life between South and North Korean societies. These results will provide useful informations for the overcome of differences of cultural life of South and North Korean societies and accomplishment of the real integration of two societies.

• Journal of Fisheries and Marine Sciences Education
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• v.27 no.6
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• pp.1556-1568
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• 2015

The objectives of this study were to inquiry of application types and use methodology of EBS-CSAT prep books of vocation education division in specialized vocational high schools. Research participants are 8 specialized vocational high school teachers in Seoul and Gyeonggi, and subjects are basic industry and basic drawing. The teachers had using EBS-CSAT prep books in class or after-school. The results are as follows: The teachers used items explanation of after-school rather than regular classes using EBS-CSAT prep books of vocation education division in specialized vocational high schools. Online lectures were used for self-directed learning of specialized vocational high school students rather than regular classes. Students and teachers of specialized vocational high school needed EBS-CSAT prep books of vocation education division by free gift instead of EBS-CSAT prep books of Korea language, english, math.

• Journal of Energy Engineering
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• v.21 no.4
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• pp.378-384
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• 2012

Higher compression ratio is required in diesel engine to ignite the fuel that leads to better efficiency. For complete combustion inside the cylinder it is important to ensure the clean air flow with free of debris and as cool as possible. In this manner, modification of intake valve arrangements is taken in to consideration importantly. In this paper, the intake valve arrangements are modified with newly designed valve mixer. It causes swirl flow of air through the intake port that mixing with the fuel followed by complete combustion. The use of valve mixer reduces the carbon sediment formation on valve fillet and its face area as the carbon particles gradually take place on it after certain running period. It therefore, helps to increase the valve lifetime. And at the same time it reduces the exhaust elements i.e. soot from the automobiles to a significant level.