• Journal of The Korean Society of Grassland and Forage Science
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• v.30 no.2
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• pp.135-142
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• 2010

This study was carried out to establish the optimum pre-wilting time for the high-quality silage production of whole crop oat. Plants were harvested for three time at intervals of 10 days after heading (DAH) and silage production was conducted after the pre-wilting treatment of 0, 4, 8 and 32 hours, respectively. Results showed to attain a proper moisture content for profitable silage production, which was an optimal content for making silage, by pre-wilting oat for 4 hours after harvest at either 20 days after heading or harvesting 30 DAH(days after heading). As the feed value of silage, the processing of proper moisture contents showed that crude protein contents were high and the entire feed value showed higher than others. High content of lactic acid and the low content of acetic and butyric acid showed on 60~65% the moisture conditions of silage. There was desired that whole crop oat was pre-wilting on 4 hours and harvested at about 20~30 DAH and after that, even if harvesting at once, it was judged that it could produce good quality silage.

• Journal of Life Science
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• v.17 no.8 s.88
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• pp.1053-1062
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• 2007

In the present work, we show that tamoxifen(Tam)-induced cytotoxicity is due to the mitochondrial-dependent pathway triggered by the intracellular $Ca^{2+}$ increase in MCF-7 human breast cancer cells. Tam induced the intracellular $Ca^{2+}$ increase. According to the experimental results with $Ca^{2+}$ channel blockers, Tam-induced $Ca^{2+}$ uptake seemed to depend on the voltage-sensitive $Ca^{2+}$ channel at the early stage, but at later stages the intracellular $Ca^{2+}$ increases are more likely due partly to the release of stored $Ca^{2+}$ and partly to the capacitative $Ca^{2+}$ or other entry pathways. Tam-induced $Ca^{2+}$ increase led to the release of cytochrome c from mitochondria into the cytosol and the change of mitochondrial membrane potential. In MCF-7 cells, caspase-7 plays a key role in the downstream of apoptosis because caspase-3 is absent. In the cells treated with Tam, caspase-7 cleavage was increased almost two-fold. There was no marked alteration in the level of anti-apoptotic Bcl-2 protein; however, the cells showed increased expression of pro-apoptotic Bax protein more than two-fold in response to Tam. These results imply that the apoptotic signaling pathway activated by Tam is likely to be mediated via the mitochondrial-dependent pathway.

• Korean Journal of Construction Engineering and Management
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• v.16 no.3
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• pp.101-112
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• 2015

In the 1950s, the concept of configuration management (CM) was started by the US Department of Defense (DOD). Later, it has begun to be applied in aerospace, software, engineering, construction, and nuclear power industry. However, configuration management (CM) in the Korean nuclear industry was firstly utilized in 2006 only for selected parts of facilities, while the US nuclear industry has applied CM for the facilities' entire systems since 1990s. Furthermore, configuration management (CM) is in its conceptual stage in the Korean nuclear industry because of ambiguous CM concepts, lacks of CM professional manpower, non-computerization, and inadequacy of CM procedures and processes. In order to address this issues, seven industries (including defense, aerospace, software, engineering, architecture, civil engineering, nuclear power) that utilize the concept of configuration management (CM) were compared and analyzed based on the CM purpose, technique, and life-cycle perspectives. By an extensive literature review and expert interviews, this paper developed a framework of configuration management (CM) for the nuclear industry. And also, a list of functions based on life-cycle stages and CM techniques are developed for clarifying CM framework in order to promote practical applications.

• Korean Journal of Food Science and Technology
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• v.33 no.1
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• pp.78-83
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• 2001

To use the by-products of whelk processing, whelk internal organ with the addition of bromelain were used to make jeotgal, Korean traditional salted and fermented seafood sauce. The products were prepared at different salt concentrations of 10, 15 and 20% with various bromelain contents 0, 0.01, 0.1 and 0.5%. The samples were stored at $10^{\circ}C$ and the chemical and microbiological analyses were evaluated for four weeks. The initial pH (near 6.1) in all conditions decreased in the beginning stage of aging, then gradually increased until three weeks and finally decreased to $5.6{\sim}6.0$. The sample with lower salt concentration showed less pH change For two weeks. The samples treated with higher bromelain in 10% and 15% salt concentration showed higher pH values after 4 weeks compared to the nontreated control. Amino nitrogen in the samples increased at lower salt concentration and at higher bromelain content. The amino nitrogen showed maximum value, 780 mg%, at 10% salt and 0.5% bromelain treatment. Total nitrogen contents increased with aging periods, especially increased rapidly in high concentrations of bromelain treated samples at early stages of aging. The higher salt concentrations in the product decreased the total microbial number and lactic acid bacterial number.

• Journal of the Korean GEO-environmental Society
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• v.21 no.7
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• pp.17-26
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• 2020

The soft ground in the southwest coastal area composed of marine clay is greatly influenced by sediment composition, particle size distribution, particle shape, adsorption ions and pore water characteristics, tide and temperature. In addition, the geotechnical properties are very complex due to stress history, change in pore water, dissolution process and gas formation. In this study, the physical and mechanical properties of the soft ground were evaluated through field tests and laboratory tests to investigate the strength increase characteristics according to consolidation on the soft ground in the southwest coast. In addition, in order to understand the consolidation behavior of soft ground such as subsidence, pore water pressure, horizontal displacement of soil by embankment load, measuring instruments such as pore water pressuremeter, settlement gauge, inclinometer and differential settlement gauge was installed, and a piezocon penetration test was carried out step by step to confirm the increase in shear strength of the ground. Through this, it was confirmed that the shear strength of the ground is increased according to the stages of filling. In addition, by evaluating the properties of consolidation behavior, strength increase and consolidation prediction by empirical methods and theories were compared to analyze the characteristics of strength increase rate and consolidation behavior in consideration of regional characteristics.

• Journal of Bio-Environment Control
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• v.32 no.1
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• pp.1-7
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• 2023

Understanding the light environment in greenhouse cultivation and the light utilization characteristics of crops is important in the study of photosynthesis and transpiration. Also, as the plant grows, the form of light utilization changes. Therefore, this study aims to develop a light extinction coefficient model reflecting the plant growth. To measure the extinction coefficient, five pyranometers were installed vertically according to the height of the plant, and the light intensity by height was collected every second during the entire growing season. According to each growth stage in the early, middle, and late stages, the difference between the top and bottom light intensity tended to increase to 69%, 72%, and 81%. When leaf area index and plant height increased, the extinction coefficient decreased, and it showed an exponential decay relationship. Three-dimensional model reflecting the two growth indexes, the paraboloid had the lowest RMSE of 1.340 and the highest regression constant of 0.968. Through this study, it was possible to predict the more precise light extinction coefficient during the growing period of plants. Furthermore, it is judged that this can be utilized for predicting and analyzing photosynthesis and transpiration according to the plant height.

• Journal of Mushroom
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• v.21 no.3
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• pp.118-125
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• 2023

We conducted an on-site application study at the livestock cooperative fertilizer plant to compare the composting period, temperature change, moisture content, and chemical properties between livestock manure compost using sawdust as a moisture regulator with those using spent oyster mushroom substrate. The composting period, moisture content, and fertilizer composition of compost containing spent oyster mushroom substrate did not differ from that of conventional compost mixed with sawdust after the first and second fermentation and post-maturation stages, it was suitable as a material for manufacturing livestock manure compost. The spent oyster mushroom substrate also lower the production cost of livestock manure compost by replacing the more expensive sawdust. The developed technology is expected to contribute towards the utilization of by-products of the oyster mushroom harvest while simultaneously producing high quality livestock manure compost.

• Education of Primary School Mathematics
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• v.26 no.2
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• pp.115-124
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• 2023

This study aimed to investigate elementary school teachers' interest in mathematics textbooks following the new change in the publication system for elementary mathematics textbooks. To achieve this, an online survey platform was used to conduct a survey of elementary school teachers in teaching grade 3-4 across the country, and the responses of 199 participants were analyzed to determine their interest in mathematics textbooks. The research results showed that elementary school teachers had high levels of interest in mathematics textbooks, particularly in informational and personal interest. Moreover, the stages at which teachers showed the highest level of interest were reinforcement interest and operational interest. Analysis of the differences in interest in mathematics textbooks based on personal variables showed significant differences depending on the teacher's experience in mathematics education training, satisfaction with mathematics textbooks, and whether they majored in mathematics education. Based on these findings, it can be inferred that elementary school teachers have a high level of informational interest in the characteristics, strengths, weaknesses, and materials related to authorized and approved mathematics textbooks, and their high level of personal interest in mathematics textbooks can have a positive effect in line with the goal of the new textbook system. Additionally, since many teachers showed a high level of interest in reinforcement interest, it is necessary to devise various ways to support teachers' creative use and reconstruction of mathematics textbooks.

• Journal of Christian Education in Korea
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• v.73
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• pp.117-137
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• 2023

This is a case study of an extra-curricular program that designed and implemented maker education based on design thinking to foster a Christian worldview. The program was designed at K university in the course of 10 sessions as following stages; tinkering, providing a special lecture for motivation, finding issues, empathizing, making, sharing and reflecting. A total of 15 students in 5 teams participated in the program, progressed through each stage in the process of solving the problems they found around them so that their neighbors and the creative world could become better. As a result of operating this program, the participants became concerned about their neighbors and community and reflected on the change of perspective of the world from a Christian worldview. As a suggestion for follow-up research and projects, to develop a model of maker education based on design thinking for cultivating a Christian view of the world is proposed in order to support to easy design and management of the program even if there is a lack of professional related knowledge and experience. In addition, it is needed to develop a manual and guide book including a facilitator's role and an assessment tool like a rubric that can give feedback on the performance of the program and make improvement.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.12 no.2
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• pp.61-72
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• 2007

The relationship between North Pacific chum salmon (Oncorhynchus keta) population and climate variability was investigated in the North Pacific ecosystem. Time-series for the Aleutian Low Pressure, Southern Oscillation, Arctic Oscillation, and Pacific Decadal Oscillation (PDO) indices dating back to 1950 are compared with the chum salmon catch using a cross-correlation function (CCF) and cumulative sum (CuSum) of anomalies. The results of CCF and CuSum analyses indicated that there was a major change in climate during the mid 1970s, and that the chum salmon population responded to this climate event with a time-lag. The PDO and chum salmon returns showed a highly significant correlation with a time-lag of 3 years, while the AOI with a time-lag of $6{\sim}7$ years. The favorable environments for fry chum salmon might cause better growth in the coastal areas, but higher growth rate during the early stage does not seem to be related to the improved return rate of spawning adults. Rather, growth in the Okhotsk Sea or the Bering Sea during immature stages has a significant correlation with return rate, which implies the size-related mortality process. The development of a local climate index is necessary to elucidate the effect of climate variability on the marine ecosystem around the Korean Peninsula.