• Journal of Life Science
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• v.13 no.4
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• pp.535-540
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• 2003

The antagonistic microorganisms against Streptococcus sanguis, S. salivarius and S. mutans causing the dental caries of oral diseases were isolated from Korean traditional soy sauce. Twenty five strains were isolated by pairing culture, paper disc culture and dual culture methods. The isolate NG 06 strain was observed with various cultural and physiological test, and $Biolog^{(R)}$ Bacterial Identification System. The strain was identified as Bacillus racemilacticus. The isolate NG 16 strain was confirmed to Gram-positive, rods, endospore production, utilization of melibiose, casein hydrolysis and starch hydrolysis. Also the second strain NG 16 was identified as $\beta$. amyloliquefaciens.

• Journal of the Korean Recycled Construction Resources Institute
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• v.9 no.3
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• pp.367-374
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• 2021

In this study, the applicability of mechanochemical process for the manufacture of self-healing admixtures and the effect of mechanochemical process on the self-healing performance were evaluated. The self-healing admixtures were adopted as a highly reactive materials(expansive agent, swelling material and crystal growth agent) for mechanochemical processes. The self-healing admixtures for the mechanochemical process application were evaluated by X-Ray Diffraction and Fourier Transform Infrared Spectroscopy analysis, water permeability performance was used to evaluate self-healing performance of mortar. As a result of the evaluation, the self-healing performance of the WM(With-Mortar)3 sample to which mechanochemical process increased by 4.1% compared to the WM1 sample that was not treated, and the average healing index was 94.3%.

• Journal of the Korean Recycled Construction Resources Institute
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• v.9 no.2
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• pp.143-151
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• 2021

Flexural test of reinforced concrete beam with corroded reinforcement were performed to measure the deflection, curvature and cracking moment for various bar diameter and amounts of corrosion. The amounts of corrosion are varied from 0% to 10% by weight and the bar diameters are chosen as 10mm, 13mm, and 19mm. The changes in reinforcement diameter do not affect the flexural behaviors significantly according to this experiment. If the amounts of corrosion is greater than 2%, the deflection and curvature of the beam increased and the cracking moment decreased. It means that the lower amounts of corrosion does not result structural damage in flexural member significantly as in direct tensile test. A modification factor considering an effect of amounts of corrosion is proposed based on the experiment, which can be used to determine the deflection of reinforced concrete beam with corroded reinforcement.

• Journal of the Korea Institute of Building Construction
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• v.18 no.6
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• pp.533-541
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• 2018

Chloride attack, one of the major deterioration phenomena in RC(Reinforced Concrete) structure, causes corrosion of reinforcement, and this leads degradation of serviceability and structural problems. The application of silicate based impregnant to concrete surface are known for excellent constructability and cost-benefit for the maintenance of RC structure. In the work, the compressive strength and resistance of chloride diffusion for concrete were evaluated after improving property of concrete surface through two types of silicate based impregnant. Furthermore, based on the previous research and the result from the work, service life analysis was performed. After impregnating of silicate, strength and resistance of chloride diffusion were remarkably improved, and the service life increase to 159% for silicate A impregnation and 304% for silicate B impregnation, respectively.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.29 no.12
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• pp.953-962
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• 2018

Recently, the Ministry of Internal Affairs and Communications of Japan has reported on a plan for the "effective use of radio waves" to be promoted in the 2020s. This includes promotion of the effective use of public frequencies, reviews of frequency allocation and transition systems, and spectrum usage fee system. Based on the proposals in this study, concrete systems for revising related laws, such as the Radio Law, will be designed and implemented. In addition, the government will jointly conduct research and development as well as verification tests in cooperation with industry, academia, and government. A plan to improve the system for the effective use of radio waves will then be devised. This study examines the policy directions of the frequency utilization system that Japan plans to use for radio waves in the 2020s. The policy directions are analyzed selectively while considering the radio waves utilization system in Korea, and implications for domestic applications are derived. Based on the research from this study, analyzing the radio policies of advanced countries, including those of England and the United States, and utilizing them to establish an effective use plan of radio waves in Korea are deemed necessary.

• Journal of the Korean Recycled Construction Resources Institute
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• v.8 no.4
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• pp.395-403
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• 2020

CaO-based by-product, which consist of CaO, SO3, Al2O3 and so on, has being used to raw materials of CaO compound. When It was applied to recycling water of remicon, concrete performance can be enhanced because hydration reaction of powder material is accelerated. In this study, activated-sludge, which was putted desulfurization gypsum of CaO-based in recycling water, was manufactured to verify effect of them, and then they was investigated by characteristics of redy-mixde concrete. As a result of concrete tests, it was confirmed that there is no problem of strength or drying shrinkage while ensuring workability. Therefore, the possibility of specific application using activated sludge was confirmed.

• KIPS Transactions on Computer and Communication Systems
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• v.10 no.12
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• pp.329-342
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• 2021

The pharmaceutical industry is experiencing a productivity crisis with a low probability of success despite a long period of time and enormous cost. As a strategy to solve the productivity crisis, the use cases of Artificial Intelligence(AI) and Bigdata are increasing worldwide and tangible results are coming out. However, domestic pharmaceutical companies are taking a wait-and-see attitude to adopt AI platform for drug research. This study proposed a research model that combines the Value-based Adoption Model and the Innovation Resistance Model to empirically study the effect of value perception and resistance factors on adopting AI Platform. As a result of empirical verification, usefulness, knowledge richness, complexity, and algorithmic opacity were found to have a significant effect on perceived values. And, usefulness, knowledge richness, algorithmic opacity, trialability, technology support infrastructure were found to have a significant effect on the innovation resistance.

• PNF and Movement
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• v.20 no.2
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• pp.203-214
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• 2022

Purpose: We investigated the effects of multimodal vs. stabilization exercises on chronic low back pain. Methods: Study participants were randomly assigned to a multimodal exercise (n = 20) or a stabilization exercise group (n = 20). Participants in the multimodal exercise group performed stabilization, stretching, and endurance exercises, whereas those in the stabilization exercise group performed only stabilization exercises. Participants in both groups performed the exercises for 1 hour thrice a week for 5 weeks. The following outcomes were evaluated: pain intensity (numeric rating scale), disability (the Oswestry Disability Index [ODI] and the Roland-Morris Disability Questionnaire [RMDQ]), pain-induced fear (the Fear of Daily Activities Questionnaire [FDAQ], the Fear-Avoidance Belief Questionnaire [FABQ], and the Tampa scale for kinesiophobia-11 [TSK-11]). Outcome measures were evaluated at baseline and after intervention. Results: Significant post-intervention improvement was observed in pain intensity and the RMDQ and FDAQ scores in both groups (p < 0.01). The post-intervention ODI, FABQ, and TSK-11 scores were improved in the multimodal exercise group (p < 0.01). Additionally, significant differences were observed in pain intensity, as well as in the ODI, FDAQ, and FABQ scores in the multimodal exercise group compared with these findings in the stabilization exercise group (p < 0.01). Conclusion: The multimodal and stabilization exercise programs reduced pain intensity, disability, and pain-induced fear. Compared with stabilization exercises, multimodal exercises more effectively reduced pain intensity, disability, and pain-induced fear. This study highlights that musculoskeletal rehabilitation for people with chronic low back pain should include a multimodal exercise program.

• The Journal of the Convergence on Culture Technology
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• v.9 no.4
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• pp.1-11
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• 2023

The purpose of this study is to develop a discussion-centered teaching and learning model for nurturing creative and convergence talents. Regarding the research method, a draft model on discussion-centered teaching and learning was devised, and the model was completed through expert validation. The final draft was revised and supplemented by verifying how valid the model was when applied in class by using the derived final draft. Compared with the draft on discussion-centered teaching and learning model, the final model focused on text-reading emphasis, methods of questioning, and question generation strategies, excluding jigsaw discussions. The discussion-centered teaching and learning model developed in this study is expected to help instructors foster creative and convergence talents. Three suggestions have been provided to effectively apply this model to the field. First, an attitude of listening and respect is required during a discussion. Second, a plan should be considered on how to induce active participation of learners participating in the discussion. Third, the importance of managing discussion time was emphasized.

• Journal of the Korean Recycled Construction Resources Institute
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• v.11 no.3
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• pp.218-225
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• 2023

In this study, we examine the feasibility of using chlorine in clinker as an early-strength cement by the effect of accelerating the cement hydration reaction of chlorine. Clinker with a chlorine content of 200-1,000 ppm was prepared using actual cement kilns, and 46 cement samples were prepared by adding gypsum and admixtures(GGBFs and limestone). We measured consistency, setting, 1-28 days compressive strength and analyzed them statistically. Test results indicated that an increase of the chlorine content resulted in shortening of initial and final setting time and the improvement of 1 day compressive strength. But the 28 days compressive strength was decreased. Specifically, when the chlorine content was increased from 230 to 965 ppm, the 1 day compressive strength increased up to 4.6 MPa, improvement effect was superior to that of increasing Blaine in the range of 3,400-3,970 cm²/g.