• Computers and Concrete
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• v.28 no.6
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• pp.533-547
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• 2021

Calculating the shear capacity of slender reinforced concrete beams without shear reinforcement was the subject of numerous studies, where the eternal problem of developing a single relationship that will be able to predict the expected shear capacity is still present. Using experimental results to extrapolate formulae was so far the main approach for solving this problem, whereas in the last two decades different research studies attempted to use artificial intelligence algorithms and available data sets of experimentally tested beams to develop new models that would demonstrate improved prediction capabilities. Given the limited number of available experimental databases, these studies were numerically restrained, unable to holistically address this problem. In this manuscript, a new approach is proposed where a numerically generated database is used to train machine-learning algorithms and develop an improved model for predicting the shear capacity of slender concrete beams reinforced only with longitudinal rebars. Finally, the proposed predictive model was validated through the use of an available ACI database that was developed by using experimental results on physical reinforced concrete beam specimens without shear and compressive reinforcement. For the first time, a numerically generated database was used to train a model for computing the shear capacity of slender concrete beams without stirrups and was found to have improved predictive abilities compared to the corresponding ACI equations. According to the analysis performed in this research work, it is deemed necessary to further enrich the current numerically generated database with additional data to further improve the dataset used for training and extrapolation. Finally, future research work foresees the study of beams with stirrups and deep beams for the development of improved predictive models.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.31 no.1A
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• pp.25-33
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• 2011

The impact damage behavior of steel-strengthened concrete panels exposed to explosive loading is investigated. Since real explosion experiments require the vast costs to facilities as well as the blast and impact damage mechanisms are too complicated, numerical analysis has lately become a subject of special attention. However, for engineering problems involving blast wave and fragment impact, there is no single numerical method that is appropriate to the various problems. In order to evaluate the retrofit performance of a steel-strengthened concrete panel subject to blast wave and fragment impact loading, an explicit analysis program, AUTODYN is used in this work. The multi-solver coupling methods such as Euler-Lagrange and SPH-Lagrange coupling method in order to improve efficiency and accuracy of numerical analysis is implemented. The simplified and idealized two dimensional and axisymmetric models are used in order to obtain a reasonable computation running time. As a result of the analysis, concrete panels subject to either blast wave or fragment impact loading without the steel plate are shown the scabbing and perforation. The perforation can be prevented by concrete panels reinforced with steel plate. The numerical results show good agreement with the results of the experiments.

• The Journal of Korean Academy of Sensory Integration
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• v.19 no.2
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• pp.26-35
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• 2021

Objective : The purpose of this study is to investigate the effect of Interactive Metronome (IM) training on the reading fluency of an elementary school student. Methods : This study followed the ABA design, a single-case research method, and was conducted on one elementary school student. From October 2019 to December 2019, a three-session baseline phase (A), twelve-session intervention phase (B), and three-session post-baseline phase (A') were conducted. The intervention was IM training, and long-form assessment (LFA) of IM and BASA:R were performed for each session. In addition, BASA:R was conducted three times at baseline and post-baseline. Result : Compared with baseline, there was a significant improvement in reading fluency after the IM training intervention. Conclusions : IM training can be useful for increasing reading fluency. The results of this work demonstrate the efficacy of IM training as a clinical intervention to improve reading fluency in elementary school students.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.5
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• pp.2101-2107
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• 2014

Background: Single nucleotide polymorphisms (SNPs) affecting microRNA (miR) sequences may influence carcinogenesis. Our current study primarily aimed to confirm previously conducted association studies between rs2910164 found on miR-146a, and rs11614913 located on miR-196a2 polymorphisms and cancer phenotypes in the Japanese elderly population. rs2910164 (G/C) and rs11614913 (T/C) polymorphisms were determined by genotyping on the samples collected from 1,351 consecutive autopsy cases registered in the Japanese SNPs for geriatric research (JG-SNP) data base. Cancer samples were systematically reviewed, pathologically verified and assessed with respect to miR-146a and miR-196a2 genotypic variation. The current study covered 726 males and 625 females with a mean age of $80.3{\pm}8.9$ years. The study included 524 subjects without cancer and 827 subjects with at least one type of cancer, such as gastric (n=160), lung (n=148), colorectal (n=116) or others. Males with cancers (n=467) were more numerous than females (n=360). Both rs11614913 (CT: TT adjusted odds ratio (OR) 95% confidence interval (95%CI)=0.98 (0.75-1.28), p=0.873, CC: TT adjusted OR (95%CI)=1.06 (0.76-1.47), p=0.737, CT+CC: TT, adjusted OR (95%CI)=0.99 (0.77-1.29), p=0.990), and rs2910164 (CG: CC adjusted OR (95%CI)=1.12 (0.87-1.44), p=0.383, GG: CC adjusted OR (95%CI)=1.03 (0.71-1.48), p=0.887, CG+GG: CC adjusted OR (95%CI)=1.10 (0.87-1.39), p=0.446) polymorphisms did not show significant association with overall cancer in all subjects. However, "CC" genotype in rs11614913 polymorphism was significantly associated with increased gastric cancer (n=160) in all subjects (CC: CT+TT, adjusted OR (95%CI)=1.50 (1.02-2.22), p=0.040). We found that rs11614913 and rs2910164 do not pose general cancer risk, but rs11614913 may influence gastric cancer in Japanese elderly population. Confirmation of our study results requires further investigations with larger subject populations.

• KEPCO Journal on Electric Power and Energy
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• v.8 no.2
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• pp.159-179
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• 2022

Often a network becomes complex, and multiple entities would get in charge of managing part of the whole network. An example is a utility grid. While the entire grid would go under a single utility company's responsibility, the network is often split into multiple subsections. Subsequently, each subsection would be given as the responsibility area to the corresponding sub-organization in the utility company. The issue of how to make subsystems of adequate size and minimum number of interconnections between subsystems becomes more critical, especially in real-time simulations. Because the computation capability limit of a single computation unit, regardless of whether it is a high-speed conventional CPU core or an FPGA computational engine, it comes with a maximum limit that can be completed within a given amount of execution time. The issue becomes worsened in real time simulation, in which the computation needs to be in precise synchronization with the real-world clock. When the subject of the computation allows for a longer execution time, i.e., a larger time step size, a larger portion of the network can be put on a computation unit. This translates into a larger margin of the difference between the worst and the best. In other words, even though the worst (or the largest) computational burden is orders of magnitude larger than the best (or the smallest) computational burden, all the necessary computation can still be completed within the given amount of time. However, the requirement of real-time makes the margin much smaller. In other words, the difference between the worst and the best should be as small as possible in order to ensure the even distribution of the computational load. Besides, data exchange/communication is essential in parallel computation, affecting the overall performance. However, the exchange of data takes time. Therefore, the corresponding consideration needs to be with the computational load distribution among multiple calculation units. If it turns out in a satisfactory way, such distribution will raise the possibility of completing the necessary computation in a given amount of time, which might come down in the level of microsecond order. This paper presents an effective way to split a given electrical network, according to multiple criteria, for the purpose of distributing the entire computational load into a set of even (or close to even) sized computational loads. Based on the proposed system splitting method, heavy computation burdens of large-scale electrical networks can be distributed to multiple calculation units, such as an RTDS real time simulator, achieving either more efficient usage of the calculation units, a reduction of the necessary size of the simulation time step, or both.

• Journal of IKEEE
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• v.25 no.4
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• pp.679-688
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• 2021

Gait is an evaluation index used in various clinical area including brain nervous system diseases. Signal source localizing and time-frequency analysis are mainly used after extracting independent components for Electroencephalogram data as a method of measuring and analyzing brain activation related to gait. Existing treadmill-based walking EEG analysis performs signal preprocessing, independent component analysis(ICA), and source localizing by merging data after the multiple EEG measurements, and extracts representative component clusters through inter-subject clustering. In this study we propose an analysis method, without merging to single dataset, that performs signal preprocessing, ICA, and source localization on each measurements, and inter-subject clustering is conducted for ICs extracted from all subjects. The effect of data merging on the IC clustering and time-frequency analysis was investigated for the proposed method and two conventional methods. As a result, it was confirmed that a more subdivided gait-related brain signal component was derived from the proposed "non-merging" method (4 clusters) despite the small number of subjects, than conventional method (2 clusters).

• 한국노년학
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• v.40 no.2
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• pp.269-289
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• 2020

The purpose of this study was to analyze the policy and programs of the Seoul50Plus Foundation and to propose policies and programs to promote active aging of middle-aged and elderly people. A single case study was utilized as a research method. The analysis framework of case was approached with four frameworks: the context of policy and program, ideology-goal analysis of policy and program, supplier and customer analysis of policy and program, and process and domain analysis of policy and program. The analysis data included the homepage content of the Seoul50Plus Foundation, related 50+ policy and program data, active aging research papers at home and abroad, and presentation and meeting materials. The results of the research showed that the policy and program background and environment were essential elements for responding to environmental changes in the aging society. In terms of the philosophy-goal, job creation, social participation, and approach to life design were systematically carried out for the ideology of 'creating a new life vision' and promoting active aging. In terms of subject-target, the subject of policy implementation is systematically composed of three stages: 50+ foundation, 50+ campus, and 50+ center. The target was limited to 50+ generations(age 50~64) and had a problem that is limited to applicants. In the process-area analysis, programs such as educational support, work and entrepreneurship support, counseling information, and new-age cultural creation activities were designed to increase added value according to the characteristics of the middle-aged people. In conclusion, the future Seoul50Plus Foundation's policy and lifelong learning programs need to be systematically promoted through cooperation with businesses and universities, expanding the target audience, matching the characteristics of the middle-aged and elderly, and linkage among programs.

• The Korean Journal of Physiology and Pharmacology
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• v.12 no.2
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• pp.83-87
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• 2008

The fyn-related kinase (FRK) belongs to the tyrosine kinase family of protein kinases. Recent studies have shown that Frk affects pancreatic beta cell number during embryogenesis and promotes beta cell cytotoxic signals in response to streptozotocin. To investigate the genetic association between FRK polymorphisms and the risk of obesity in Korean population, single nucleotide polymorphisms (SNPs) in the FRK gene region were selected and analyzed. The body mass index (BMI) was calculated, and biochemical data (systolic blood pressure, diastolic blood pressure, hemoglobin A1C, triglyceride, total cholesterol, high density lipoprotein, and low density lipoprotein) of blood sample from each subject were also measured. One hundred fifty five healthy control and 204 overweight/obesity subjects were recruited. Genotype frequencies of six SNPs [rs6568920 (+8391G>A), rs3756772 (+56780A>G), rs3798234 (+75687C>T), rs9384970 (+68506G>A), rs1933739 (+72978G>A), and rs9400883 (+75809A>G)] in the FRK gene were determined by Affymetrix Targeted Genotyping Chip data. According to the classification of Korean Society for the Study of Obesity, control (BMI 18 to < 23) and overweight/obesity (BMI$\geq$23) subjects were recruited. For the analysis of genetic data, EM algorithm, SNPStats, Haploview, HapAnalyzer, SNPAnalyzer, and Helixtree programs were used. Multiple logistic regression analysis (codominant, dominant, and recessive models) was performed. Age and gender as covariates were adjusted. For biochemical data, Student's t test was used. The mean value of BMI in the control and overweigh/obesity groups was 21.1${\pm}$1.2 (mean${\pm}$SD) and 25.6${\pm}$2.0, respectively. All biochemical data of the overweight/obesity group were statistically significance, compared with the control group. Among six SNPs, two linkage disequilibrium (LD) blocks were discovered. One block consisted of rs1933739 and rs9400883, and the other comprised rs3756772 and rs3798234. One SNP (rs9384970, +68506G>A) showed an association with overweight/obesity in the codominant model (p=0.03). Interestingly, the AA genotype distribution in the overweight/obesity group (n=7, 3.5%) was higher than those in the control group (n=1, 0.6%), which is not found in either Japanese or Chinese subjects. Therefore, the AA genotype of rs9384970 may be a risk factor for development of obesity in Korean population. The results suggest that FRK may be associated with overweight/obesity in Korean population.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.22 no.2
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• pp.295-301
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• 2018

In various disciplines, researchers, not single researchers, tend to cooperate to study the same topic. There are many studies to analyze the collaborative form of various researchers through the social network analysis method, but there are few such studies in the computer field. In this paper, we analyze the characteristics of network and various groups of researchers through the social network analysis technique of the co-authors of the Journal of Korea Institute of Information and Communication Engineering, and analyze the degree centrality, the between centrality and edge weight. As a result of the analysis, many groups were extracted from the co-author's network, but the top 20 groups accounted for more than 50% of the total, also, we could find a pair of researchers who do joint research with a very high frequency. These Co-author networks are expected to be the basis for in-depth research on the subject and direction of research through future researches.

• Korean Journal of Environmental Biology
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• v.23 no.4
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• pp.398-404
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• 2005

Radioprotection is of practical importance for the normal tissues of tumor patients subject to radiotherapy, people with planned or accidental exposure to radiation, and the public and radiation workers. Since oxygen enhances radiation - induced biological damage, antioxidants should be related with the function as a radioprotectors. Ascorbic acid or caffeine is an essential component and antioxidant in the diet of humans and a small range of other mammals. The present study investigates functional radioprotection of caffeine and ascorbic acid against gamma radiation in irradiated C57BL/6N mice. Eight-week-old male C57BL/6N mice were irradiated with 6.5 Gy. A caffeine treated group was administered with $80mg\;kg^{-1}$ body weight by intraperitoneal injection, a single treatment 1 hr before irradiation. Ascorbic acid was administered $330\;mg\;L^{-1}$ in drinking water through all the experimental period. According to time schedules, animals were sacrificed by cervical dislocation. And the samples were collected 2 weeks after whole- body gamma irradiation. The caffeine treated group showed lower decrement of body and organ weights than the other experimental groups. The qualitative analysis of circulating testosterone in serum was performed by means of radioimmunoassay (RIA). The normal level of circulating testosterone was maintained by the treatment of caffeine and ascorbic acid. The change of weight of body and organ and the appearance of seminiferous tubules were improved by an effect of caffeine or ascorbic acid against irradiation. Taken together, caffeine and ascorbic acid protects impairment of spermatogenesis against gamma radiation and may act as a radio-protector.