• Journal of the Korea Concrete Institute
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• v.21 no.6
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• pp.681-688
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• 2009

The railroad bridges have been usually experienced by vibration and impact in service state. With this reason, it is important that the effective strengthening capacity should be considered to resist the kind of service loading. In this study, NSM strengthening technique is recommended for the concrete railroad bridge because of its better effective resistance for dynamic loading condition and strengthening cost than the conventional externally bonded strengthening using fiber sheet. However, to widely apply NSM method for the concrete railroad bridge, it needs that the strengthening ratio has to be reasonably evaluated with geometrical and material uncertainties, especially for the concrete bridge under long-term service state without the apparent design history and detail information such as concrete compressive strength, reinforcing ratio, railroad characteristics. The purpose of this study is to propose the critical strengthening ratio of CFRP plate for the targeted concrete railroad bridge with uncertainties of deterioration of the structures. To do this, Monte Carlo Simulation (MCS) for geometrical and material uncertainties have been applied so that this approach may bring the reasonable strengthening ratio of CFRP plate considering probabilistic uncertainties for the targeted concrete railroad bridge. Finally, the critical strengthening ratio of NSM strengthened by CFRP plate is calculated by using the limit state function based on the target reliability index of 3.5.

• Journal of the Korea Concrete Institute
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• v.29 no.3
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• pp.259-266
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• 2017

The purpose of this study was to contribute to the field application cost effectively and reasonably by developing the functional piles that reinforces shear force. CFP pile (Concrete Filled Pretensioned Spun High Strength Concrete Pile with Ring type Composite shear connectors) developed in this study increases the shear stress by placing composite shear connector and filling the concrete into hollow part of the pile. By placing the reinforcement (H13-8ea) and the reinforcement (H19-8ea) into hollow section inside of PHC piles, it also improves the shear strength due to increasing steel ratio. It reinforces shear strength effectively by dowel force that is generated by putting reinforcement (H13-8) into the holes of composite shear connectors for the composite behavior of filled concrete and PHC pile. The study was reviewed and compared the calculated result of the shear strength by limit state design method highway bridge design standards (2012) and experiment result of the shear strength by KS F 4306. We can design the shear strength reasonably as the safety ratio of 2.20, 2.15, 2.05 is shown comparing to design shear strength, according to design shear strength on each cross sections and the experiment results of the CFP pile.

• Korean Journal of Childcare and Education
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• v.12 no.1
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• pp.57-81
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• 2016

The purpose of this study was to find out the feature of children's play according to a player number restriction rule in the free choice activities. And it is expected that the result of this study will contribute to improving the management of free choice activities. The participants of this study were a homeroom teacher, professor as a co-researcher and 25 4-year-old children of a private kindergarten. The data were collected by observation, children interview and reflective journal of the teacher from July to October in 2014. The results indicated that the children were stressed out with using name cards for presenting center selection, showed overcompetitive behaviors, and frequently violated the rules. The researchers found that the restriction rule had some dysfunctions, which were interferences of moral development, social-emotional development, self-regulation development, preventing safety-accident and free choice behavior. The researcher as a teacher abandoned the player number restriction rule, and observed the children's play. As a result, children's self-regulation abilities on physical space, play and conflicts improved and the teacher changed her strategy when managing free choice activities. Based on the results, the needs of various restriction rules and appropriate methods for applying the rules in free choice activities were further discussed.

• Journal of the Korea Concrete Institute
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• v.27 no.3
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• pp.253-263
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• 2015

Ultra-high strength concrete which have 100 MPa compressive strength or higher can be developed applying RPC(Reactive Powder Concrete). Preventing brittle failure under compression and tension, ultra-high strength concrete usually use the steel fibers as reinforcements. For the effective use of steel fiber reinforced ultra-high strength concrete, estimation of tensile strength is very important. However, there are insufficient research results are available with no relation between them. Therefore, in this study, correlation between compressive strength and tensile strength of ultra-high strength concrete was investigated by test and statistical analysis. According to test results, increasing tendency of tensile strength was also shown in the range of ultra-high strength. Evaluation of test results of this study and collected test results were carried out. Using 284 splitting test specimens and 265 flexural test specimens, equations suggested by previous researchers cannot be applied to ultra-high strength concrete. Therefore, using database and test results, regression analysis was carried out and we suggested new equation for splitting and flexural tensile strength of steel fiber reinforced ultra-high strength concrete.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.2 no.1 s.2
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• pp.41-52
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• 2003

The purpose of this study was to test the effects of the pedestrian green signal adjustment on clearance of the turning vehicles impeding the through traffic flow at the signalized intersections, and thereby, suggest some operational criteria for adjustment of the pedestrian green signal. In order to test such effects, the pedestrian green time was adjusted so that it could started a few seconds later than the vehicle green time during peak hours, and thereby, the turning vehicle volume not cleared at the intersection was measured by extending the time gap by 2 seconds. (In general, the pedestrian green signal turns on at the same time as the vehicle green signal.) The results of this test can be summed up as follows; first, the longer the time gap was, the turning vehicle volume not cleared from the intersection decreased more. Second, in case there existed a storage space between intersection and crosswalk the effect of the turning vehicles on the through traffic flows was minimal. Third, at the pelican, the effect of the turning vehicles on the through traffic flow was minimal due to the structure of the intersection and the phase sequence. In conclusion, it was found that the adjustment of pedestrian green signal had the effect of enhancing the intersection operation. When adjusting the pedestrian green signal, it was deemed necessary to thoroughly survey the geometric structure of the intersection and collect the data on the turning traffic volume and thereby, apply the results of analysis flexibly to each intersection.

• Culinary science and hospitality research
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• v.20 no.6
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• pp.56-68
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• 2014

Yam Yackwa (YP) was made by addition of yam power (15%) into flour. Depending on extension of storage time, lightness and redness of YP were increased. Yellowness of YP was decreasing until 3 days and increased from 9 days of storage. However, the yellowness of Yackwa without Yam powder (Non-YP) was increasing until 3 days and decreased from 6 days of storage. Hardness, gumminess, and chewiness of YP were improved compared to Non-YP. It means that the addition of yam power makes Yackwa soft. Oil absorption of Non-YP was low. Acid value and peroxide value of YP were 1.57 and 19.04, respectively. Moisture contents, crude ash, crude fat, crude protein, and carbohydrate of YP were $2.55{\pm}0.08%$, $0.71{\pm}0.01%$, $6.11{\pm}0.06%$, $15.97{\pm}1.40%$, and $64.66{\pm}0.09%$, respectively.

• Journal of Plant Biotechnology
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• v.45 no.3
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• pp.155-170
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• 2018

In this paper, mechanisms of gene editing technologies including ZFN, TALENS and CRISPR were briefly discussed with mutual advantages and disadvantages. Classification criteria of gene edited, site-directed mutagenesis (SDN) crops for regulatory purpose were also discussed. The number of studies using CRISPR technology was high and studies conducted on Arabidopsis thaliana and rice were highest, followed by tobacco, tomato, wheat, and corn. It has been applied to a variety of plants such as other grain crops, flower crops, vegetable crops, and fruit trees. The number of studies focused on practical application or commercialization in the future were also increasing yearly, and the scope of studies also expanded to include research on metabolic engineering for mass production of useful proteins or substances, development of disease resistant crops against viruses, bacteria, and fungi, abiotic environmental stressresistant crops, and increased yields. In addition to this, it was revealed that application range is becoming more diversified, including the development of parthenocarpic tomatoes, hybrid rice lines using male sterility and increased shattering resistance Brassica napus. It was also revealed that the number of CRISPR gene edited crops permitted by the USDA(APHIS) increases yearly, to be released in the international seed market soon.

• Journal of Korea Society of Industrial Information Systems
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• v.17 no.1
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• pp.47-62
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• 2012

To propagate clinical disease management service, there should be built a ecosystem where service developers, service providers, device suppliers closely cooperate for u-Health platform. However, most u-Health platform is difficult to build an effective ecosystem due to the lack of secure and effective PHR(Personal Health Record) management, the lack of personalized and intelligent service, difficulties of N-screen service. To solve these problems we suggest the CDMP(Chronic Disease Management Platform) architecture. The CDMP is a software platform that provides the core functions to develop the chronic disease management services and performs a hub function for the link and integration rbetween various services and systems. CDMP is SOA based platform that enables a provision of reusability, expansibility and it provides open API where everybody can share information, contents and services easily. CDMP supports the multi platform system foN-screen service and the self management functions via SNS. In this paper, we design and implement the CDMP including PHR service based on hybrid data model for privacy preservation. Experiment results prove the effectiveness of hybrid model-based PHR service.

• Korean Security Journal
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• no.11
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• pp.227-243
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• 2006

In modern society, private securities have developed their capabilities continuously. However, despite the fact that not only security industries have been considerably expanded in quantity, but also plenty of scholars published diverse papers relating to security problems, qualitative growths of private securities have not accomplished fully. Especially, securing the President would not be guaranteed only by PSS(Presidential Security Service). In order to secure the President successfully, it is necessary for all the social parts to strive to protect the President. In this respect, improving private securities, including academic fields, might be critical so as to succeed in securing the President. Without the supports from private securities, there might be lots of security problems in national context. Therefore, this study proposes several policy suggestions for the cooperation among PSS, private security industries and academic fields: (1) Providing a lot of practical knowledge from PSS to college students, (2) Personnel exchange between academic parts and PSS to promote the efficiency of securing the President, (3) Furnishing diverse information and knowledge about security to private securities, (4) Formulating security-searching standards, (5) Expanding educational institutions under PSS.

• Food Science of Animal Resources
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• v.29 no.1
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• pp.34-39
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• 2009

The objective of this study was investigated to apply the fucoidan and laminarin extract from low-grade Undaria pinnatifida to real food product, a pork patty. Pork patties added with fucoidan and laminarin showed lower lipid oxidation and the inhibition against lipid oxidation was shown to be dependent on the irradiation doses. The Hunter color values of pork patty added with fucoidan increased significantly with an increase of irradiation dose. The hardness profiles of the patties with fucoidan and laminarin was decreased, but the amount of water in the patties was increased. Also, the combination of gamma irradiation and addition of fucoidan and laminarin was shown to be effective for the microbiological control. These results suggested that gamma irradiation and fucoidan and laminarin treatment showed the positive effect on microbial stability and quality of the pork patty.