• Journal of the Korean Recycled Construction Resources Institute
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• v.1 no.1
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• pp.49-57
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• 2013

Recently, recycling of industrial by-products and CO2 reduction have been important issues in the world. In this reason, applications and reuse of Fly ash as a binder for concrete, which is generated in thermoelectric power plant, have been one of the effective recycle methods. In order for Fly ash to be applied to concrete, Korean Standard(KS) has selected and managed quality such as $SiO_2$, fineness, specific gravity, ignition loss and activity index. However, there is a limits for activity index, whose test period required is at least 28 days or 91 days. Activity index is the critical indication standard to determine mechanical strength of concrete that contained Fly ash. To complement the disadvantage of test method, this research provided "API test method", which quickly measure Pozzolanic reaction of Fly ash can be considered as a alternative of activity index. Then, the adaptable API test method need to be investigated through comparative analysis with the test result of API, activity index and K-value. The test method can make evaluation of Fly ash quality faster and more accurate. As a result, most Fly ash produced in Korea has not been satisfied in the KS quality standard except water content and specific gravity, and especially fluidized bed boiler ash has its characteristics. Also, API, activity index and K-value have superior interrelationship. The interrelationship between API and activity index and K-value gets increased as the material age gets higher, so API test can be considered as very useful test method for Pozzolanic reaction evaluation of Fly ash.

• Journal of Distribution Science
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• v.20 no.9
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• pp.73-81
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• 2022

Purpose: This study aimed to examine whether key audit matters (KAMs) readability influences investor reaction. Research design, data, and methodology: The signaling theory was applied to explain the behavior of investors when they receive useful information for their decisions. Data were collected from 1,866 firm-year observations from Thai listed companies in both the Stock Exchange of Thailand (SET) and the Market for Alternative Investment (MAI) for the fiscal years of 2016-2019. The study was based on secondary data, which were collected from the SET Market Analysis and Reporting Tool (SETSMART) database and the Stock Exchange of Thailand's website (www.set.or.th). A statistical regression method was used with panel data analysis to evaluate possible associations between KAMs readability and investor reaction. The study relied on popular readability measures (Fog Index). Moreover, investor reaction was measured by absolute cumulative abnormal return and abnormal trading volume. Results: It was found that the KAMs readability has positive significance on both absolute cumulative abnormal return and abnormal trading volume. Conclusion: This study showed a significant contribution to the implication of KAMs in an emerging economy. The results reveal that more readable KAMs disclosure distributed new insights and useful information to investors and led to reducing the information gap between auditors and investors.

• Journal of applied mathematics & informatics
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• v.15 no.1_2
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• pp.1-28
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• 2004

We first apply a first order splitting to a semilinear reaction-diffusion equation and then discretize the resulting system by an $H^1$-Galerkin mixed finite element method in space. This semidiscrete method yields a system of differential algebraic equations (DAEs) of index one. A priori error estimates for semidiscrete scheme are derived for both differ-ential as well as algebraic components. For fully discretization, an implicit Runge-Kutta (IRK) methods is applied to the temporal direction and the error estimates are discussed for both components. Finally, we conclude the paper with a numerical example.

• Journal of Korean society of Dental Hygiene
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• v.15 no.6
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• pp.1063-1071
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• 2015

Objectives: The purpose of the study is to investigate the quantitative detection of periodontal pathogens before and after scaling by real-time polymerase chain reaction. Methods: Participants were voluntarily recruited at D university, and saliva samples were extracted before and after scaling. Multiple real-time polymerase chain reactions were used to analyze characteristics and the amount of nine kinds of periodontal pathogens; Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Tannerella forsythia, Treponema denticola, Prevotella intermedia, Fusobacterium nucleatum, Parvimonas micra, Campylobacter rectus, and Eikenella corrodens. Results: After scaling, most periodontal pathogens except Eikenella corrodens were significantly decreased in all subjects(p<0.05). In addition, the percentage of microorganisms associated with disease, the microorganism risk index of periodontitis and the prevalence of red complex, orange complex, and Aggregatibacter actinomycetemcomitans was also significantly reduced after scaling(p<0.05). Conclusions: Scaling decreased in the amount of major periodontal pathogens and periodontitis prevalence rate.

• Structural Engineering and Mechanics
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• v.16 no.4
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• pp.441-468
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• 2003

This paper investigates the structural behavior of modular falsework system under sequential pattern loads. Based on the studies of 25 construction sites, the pattern load sequence modeling is defined as models R (rectangle), L and U. The study focuses on the system critical loads, regions of largest reaction forces, discrepancy between the pattern load and the uniform load, and the warning-system plan. The analysis results show that the critical loads of modular falsework systems with sequential pattern loads are very close to those with the uniform load used in design. The regions of largest reaction forces are smaller than those calculated by the uniform load. However, the regions of largest reaction forces of three models under sequential pattern loads can be considered as the crucial positions of warning-system based on the measured index of loading. The positions of the sensors for the warning-system for these three different models are not identical.

• Journal of the Korean Society for Precision Engineering
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• v.22 no.5 s.170
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• pp.197-204
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• 2005

In this study, ground reaction force(GRF), absolute symmetry index(ASI) and coefficient of variation(CV) of fixed, single-axis and multi-axis prosthetic ankle assemblies were investigated to show the biomechanical evaluation for above knee amputees. In the experiments, 37 normal male volunteers, two male and two female AK amputees were tested with fixed, single-axis and multi-axis prosthetic ankle assembly. A gait analysis was carried out to derive the ratio of GRF to weight as the percentage of total stance phase for ten points. The results showed that fixed-axis ankle was superior to the other two ankle assemblies for the characteristic of forwarding and breaking forces. Multi-axis ankle was relatively superior to the other two ankle assemblies for gait balancing and movement of the center for mass. single-axis ankle was relatively superior to the other two ankle assemblies for CV and ASI of GRF.

• Journal of Korean Medicine Rehabilitation
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• v.21 no.4
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• pp.157-165
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• 2011

Objectives: The aim of this study is to establish the association of GNB3 with obesity-index, blood pressure, glucose and lipid level. Methods: A total of 209 Korean obese subjects participated in the study. Body weight, body mass index(BMI), waist circumference, body fat, body fat mass, resting metabolic rate, blood pressure, total cholesterol, high density lipoprotein, triglyceride and fasting blood sugar test were measured by using standardized protocols. The GNB3 was genotyped by using polymerase chain reaction with restriction fragment length polymorphism. Results: The frequency of CC, CT, TT genotype were, respectively, 18,2%, 56.9%, 24,9%, and the frequency of T allele was 53.3% in Korean obese population. There were no association of GNB3 with obesity index, blood pressure, glucose and lipid level in Korean obese population. Conclusions: Obese Korea population have a higher frequency of T alle than general Korean population. There are no association of GNB3 with obesity index, blood pressure, glucose and lipid level in Korean obese population.

• Journal of the Chungcheong Mathematical Society
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• v.10 no.1
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• pp.87-95
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• 1997

In general, the positive solution to biological reaction-diffusion equations is not unique. In this paper, we state the sufficient and necessary conditions of the existence of positive solutions, and give and the proof for the uniqueness of positive solutions for a certain elliptic interacting system.

• Journal of Food Hygiene and Safety
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• v.5 no.1
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• pp.41-48
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• 1990

Propyl gallate used as an antioxidant was examined for its effects on murine immune system. As immunotoxicology assay parameters, we adopted circulating leukocytes and immunoorgan weights for pathotoxicology, delayed hypersensitivity and colloidal carbon clearance for cell mediated immuntity. Propyl gallate's effects were observed as follows; 1) Propyl gallate decreased circulating leukocyte counts, dose dependently. 2) Propyl gallate decreased delayed hypersensitivity reaction. 3) Phagocytic index were similar in the test and control groups.

• Journal of Sensor Science and Technology
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• v.20 no.2
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• pp.107-113
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• 2011

LSPR(Localized Surface Plasmon Resonance) sensor measures the refractive index change on the sensor surface. The detection of biological reaction with the unknown refractive index needs to be converted into the signal sensitivity for the refractive index change for comparison with other measurements. To find the signal sensitivity, the three steps of signal processing are proposed, which are signal modeling, signal calibration and signal normalization of LSPR sensor. The detected signal of biotin-streptavidin interaction has been converted into unit of [RU](Resonance Unit) using the proposed method. The converted signal directly can be compared with the other sensors including commercialized one.