• Investigative Magnetic Resonance Imaging
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• v.16 no.1
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• pp.31-39
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• 2012

Purpose : To determine the optimal combination of commercially available superparamagnetic iron oxide (SPIO) nanoparticles with transfection agents (TA). Materials and Methods: Protamine sulfate (Pro) and poly-L-lysin (PLL) were incubated with ferumoxide and ferucarbotran in human mesenchymal stem cells at various concentrations, and cellular viability were evaluated. Cellular iron uptake was qualitatively and quantitatively evaluated. Cell visibility was assessed via MR imaging and the T2-relaxation time was calculated. Results: The cellular viabilities with ferucarbotran were more significantly decreased than those with ferumoxide (p < 0.05). Iron uptake with ferumoxide was significantly higher than that for those with with ferucarbotran. The T2-relaxation time was observed to be shorter with ferumoxide in comparison to those with ferucarbotran (p < 0.05). Ferumoxide at a concentration of 25 ${\mu}g$/ml in combination with either Pro or PLL at a concentration of 3.0 ${\mu}g$/ml did not adversely impact cell viability, maximized iron uptake, and exhibited a lower T2-relaxation time in comparison to other combinations. Conclusion: Stem cells with ferumoxide exhibited a higher cellular viability and iron uptake in comparison to ferucarbotran-treated stem cells. A 25 ${\mu}g$/ml of ferumoxide with a 3.0 ${\mu}g$/ml of TA is sufficient to label mesenchymal stem cells.

• Korean Journal of Construction Engineering and Management
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• v.13 no.4
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• pp.100-109
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• 2012

Large road construction projects are typically partitioned into sections that are then contracted individually to contractors. Each section requires using similar heavy equipment including excavators, dump trucks and pavers, which constitute the highest cost. Normally the equipment is not shared between them, as each contractor wishes to have their equipment readily available. However, such practices result in very low utilization of these equipment. The goal of this research is to develop a programmatic resource sharing system in which contractors can share equipment depending on the changing needs of a multi-sectioned road project. This paper introduces the results of a survey performed to investigate how contractors currently manage the supply and demand of equipment and the equipment that are practical for sharing across a project. More importantly, the paper describes a set of metrics (DPR, nDPR, SDI) needed to quantify the amount of supply/demand variance occurring in each section. The metrics were used on an actual road construction project, and the results show that each section suffers from an imbalance between its monthly planned and actual utilization of equipment. The results also indicate that the sharing of the equipment can lead to potentially large savings as equipment requirements can be met within a project as to short leasing from outside vendors.

• Journal of the Korea Concrete Institute
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• v.24 no.4
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• pp.399-406
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• 2012

Beam-column joints are generally recognized as the critical regions in the moment resisting reinforced concrete (RC) frames subjected to both lateral and vertical loads. As a result of severe lateral load such as seismic loading, the joint region is subjected to horizontal and vertical shear forces whose magnitudes are many times higher than in column and adjacent beam. Consequently, much larger bond and shear stresses are required to sustain these magnified forces. The critical deterioration of potential shear strength in the joint area should not occur until ductile capacity of adjacent beams reach the design demand. In this study, a method was provided to predict the deformability of reinforced concrete beam-column joints failing in shear after the plastic hinges developed at both ends of the adjacent beams. In order to verify the deformability estimated by the proposed method, an experimental study consisting of three joint specimens with varying tensile reinforcement ratios was carried out. The result between the observed and predicted behavior of the joints showed reasonably good agreement.

• Journal of Elementary Mathematics Education in Korea
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• v.16 no.3
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• pp.389-401
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• 2012

The focus of the present study is on examining a research trend of teachers' professional development in mathematics. In do this, this study investigated the meaning and standards of professional development about mathematics, examining the characteristics of successful mathematics education professional programs, and looking for the processes of teachers' professionalization about mathematics. The findings of this study point out as follows: Teachers' professional development about mathematics implies the improvement of the quality of mathematics instruction following improving the quality of mathematics learning through well-structured mathematics teacher education programs. To do this, teachers need to have shared vision about how to teach mathematics, to have profound knowledge related to the mathematics subject, and to actively participate in teachers' professional development programs in mathematics. The results suggest the common characteristics of successful programs of mathematics teachers' professional development. The results of this study suggest that teachers need to have passion and efforts to improve teachers' professionalization about mathematics, and research on teacher professional development should be based on understanding about teachers. Also, more teacher-researchers to connect educational theories with educational practices are recommended, and a model for teachers' professional development program of mathematics appropriate to the context of Korea needs to be developed.

• Information Systems Review
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• v.17 no.2
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• pp.219-238
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• 2015

As Internet and IT have been developed, people have been exposed to large amounts of information. So, many online information providers recommend relevant information to users to relieve an information overload. However, information recommendation which is based on the taste and preference of a user can lead to a problem of unbalanced information consumption. Prior research about online information has not investigated the side-effect of a recommendation function. This research suggests IT solutions for alleviating unbalanced information consumption behavior. Based on adaptation level theory and expectancy theory, we proposed self-reference point diagnosticity interface and social-reference point diagnosticity interface to help people to consume information following their own information consuming goal. We hypothesized positive impacts of these two interfaces on the self-awareness about information consuming pattern. And we predicted that self-awareness has a positive impact on the motivation and actual behavior to conform the ideal information consuming pattern which the user sets. Laboratory experiment was executed as a research method. As a result, the self-reference diagnosticity interface leaded to higher self-awareness and mitigated the unbalanced information consumption. But, the social-reference diagnosticity interface and the motivation to improve the information consuming behavior had no significant results. Academic and practical implications are discussed.

• Culinary science and hospitality research
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• v.21 no.6
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• pp.206-217
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• 2015

This study sought to determine the physicochemical and sensory qualities of yogurt dressing prepared with different levels Aronia juice(0, 10, 20, 30, and 40%). As the amount of added Aronia juice increased, malic acid, acetic acid, and citric acid contents increased, although tartaric acid and lactic acid contents decreased. The viscosity of the control group(4,296.67 cP) was higher than those of the other groups(1,466.67~3,496.67 cP). The pH of the yogurt dressing containing 10% Aronia juice(3.83) was higher than those of the other groups(3.59~3.74). The sweetness of the yogurt dressing containing 10% Aronia juice($5.17^{\circ}Brix$) was higher than the other groups($2.47{\sim}3.47^{\circ}Brix$). Lightness decreased significantly, whereas a value and b value increased significantly with added levels of Aronia juice. DPPH radical scavenging activity of the control group was 7.42%, whereas those of the yogurt dressing samples with Aronia juice ranged from 26.30-69.86%. The sensory property results showed that the 20% Aronia juice added yogurt dressing group had the highest value in terms of color, thickness, taste, mouth feel, and overall acceptability. Overall, the results of this study indicates that the yogurt dressing containing 20% Aronia juice was the most preferred among the groups.

• Culinary science and hospitality research
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• v.20 no.2
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• pp.214-231
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• 2014

This study was intended to investigate the alcohol drinking characteristics, Makgeolli drinking behavior, and perception of Makgeolli focusing on the Chinese students studying in Korea. 550 copies of self-administrated questionnaire for a survey were distributed from May 2nd to June 30th, 2012, and then 461 copies were adopted for the analyses. The drinking frequency and drinking amount at a time increased as the length of stay in Korea and monthly pocket money increased, and Makgeolli was second preferred, following beer. 97.5% of the students experienced drinking Makgeolli, the drinking rate and drinking amount of Makgeolli increased with the length of stay in Korea, and they mostly drank at restaurants and bars. Common motivations for drinking Makgeolli were taste and atmosphere while drinking it, and bad taste and headache were the most common reasons for disliking Makgeolli. The awareness of commercial Makgeolli types was low, and for the price and health promoting effects of Makgeolli, 92.4% and 85.8% of the students replied positively, respectively. These results suggest that the development of high quality Makgeolli adapted to the tastes of Chinese and relieving hangover, and advertising the health benefits would promote Makgeolli consumption in Chinese market.

• The Journal of the Acoustical Society of Korea
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• v.35 no.3
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• pp.223-233
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• 2016

Design of a vegetation type sound barrier was presented as a noise barrier on the boundary of neighborhood facilities including schools, and apartments. The suggested noise barrier is made of unit blocks that are to be formed by stacking over the wall structure containing the plant and soils in the blocks. The advantage of the vegetation noise barrier is to acquire not only sound absorptive effects of plants and soils, but also sound diffusive effect caused by the irregular surface of the barrier which could eventually mitigate the noise. First, the optimum size of the units to obtain the highest noise reduction was investigated using 1/10 scaled model experiment, and sound attenuation experiments were carried out using a 1/2 mock-up model which is 2 m high and 5 m long. Total 1,137 unit blocks were made of synthetic woods with the size of $10{\times}10{\times}9cm$. These unit blocks were installed on the both side of the 1/2 mock-up steel framed noise barrier. As a result, it was revealed that the block typed vegetation noise barrier has 7 dB higher insertion loss in comparison with the general plane noise barrier. Also, it was found that the appropriate size of unit blocks is $20{\times}20cm$ which has large effect of sound insertion loss.

• Korean Journal of Food Science and Technology
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• v.48 no.3
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• pp.256-261
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• 2016

This study investigated the changes in functional components of barley powder produced from different grain varieties (Dahan, Hinchalssalbori, Heukgwang, Huknuri and Boseokchal) and varying milling degrees (27, 23, 19, and 15%). Total polyphenol contents increased with a decrease in the milling degree, with content ranges of 0.97-1.40, 1.19-1.66, 1.22-1.77, 1.30-1.93, and 1.46-2.12 mg/g, respectively. Total flavonoids content also increased with a decrease in the milling degree. The total polyphenol and flavonoids contents were the highest in barley powder from Huknuri and Boseokchal grains. Total dietary fiber, arabinoxylan, and GABA contents increased with a decrease in the milling degree. As the milling degrees decreased, ${\beta}$-glucan contents, which was the highest in Hinchalssalbori and Boseokchal, decreased with ranges of 4.98-7.29, 5.26-7.03, 4.84-7.17, 4.84-700, and 4.66-6.33 mg/100 g, respectively. These results provide useful data for selection of an appropriate variety and milling degree to achieve a high quality in barley processing.

• Journal of Mushroom
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• v.14 no.2
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• pp.64-69
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• 2016

Pleurotus eryngii is one of the most widely cultivated and important edible mushrooms. However, the shelf life of the fruiting body is short, which. To solve this problem, a new cultivar, DanBi 5Ho, of Pleurotus eryngii was developed by mono-mono crossing between monokaryotic strains derived from KNR2598 and KNR2610. The optimum temperature formycelial growth was 25 and that forfruiting body development was 15-16. The quality did not change after a period of 40.0 d at 4. This result was significantly different compared to that ofthe control strain Knneuari 2 Ho. Analysis of genetic characteristics of the new hybrid strain DanBi 5Ho revealeda different profile thanthat of the parental and control strains when random amplification of polymorphic DNA (RAPD) primers we used. The results obtained from this study show that DanBi 5Ho is a new hybrid strain, characterized by improved storability after harvesting.