• Structural Engineering and Mechanics
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• v.78 no.3
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• pp.231-253
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• 2021

Pure bending loading conditions are not frequently occurred in practical engineering, but the flexural researches are important since it's the basis of mechanical property researches under complex loading. Hence, the objective of this paper is to investigate the flexural behavior of concrete-filled rectangular steel tube (CFRT) through combined experimental and numerical studies. Flexural tests were conducted to investigate the mechanical performance of CFRT under bending. The load vs. deflection curves during the loading process was analyzed in detail. All the specimens behaved in a very ductile manner. Besides, based on the experimental result, the composite action between the steel tube and core concrete was studies and examined. Furthermore, the feasibility and accuracy of the numerical method was verified by comparing the computed results with experimental observations. The full curves analysis on the moment vs. curvature curves was further conducted, where the development of the stress and strain redistribution in the steel tube and core concrete was clarified comprehensively. It should be noted that there existed bond slip between the core concrete and steel tube during the loading process. And then, an extensive parametric study, including the steel strength, concrete strength, steel ratio and aspect ratio, was performed. Finally, design formula to calculate the ultimate moment and flexural stiffness of CFRTs were presented. The predicted results showed satisfactory agreement with the experimental and FE results. Additionally, the difference between the experimental/FE and predicted results using the related design codes were illustrated.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.41 no.2
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• pp.93-100
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• 2021

The objective of this research is to evaluate of fire damage for steel-concrete composite bridge superstructure and PSC bridge superstructure under highway bridge exposed to fire loading. To enhance the accuracy and efficiency of the numerical analysis, the proposed heat flow fire analysis method is implemented in ANSYS. The proposed heat flow analysis method is applied to fire damage analysis and performance evaluation for Buchen and Yangsan highway bridge. The result of analysis, temperature of concrete slab and lower flange of steel-concrete composite bridge superstructure are exceed the critical temperature. Also, temperature of slab, lower and upper flange, web of PSC bridge superstructure are exceed the critical temperature. However, the major component, tendon, did not exceed the critical temperature.

• Genomics & Informatics
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• v.19 no.1
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• pp.11.1-11.8
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• 2021

For the novel coronavirus disease 2019 (COVID-19), predictive modeling, in the literature, uses broadly susceptible exposed infected recoverd (SEIR)/SIR, agent-based, curve-fitting models. Governments and legislative bodies rely on insights from prediction models to suggest new policies and to assess the effectiveness of enforced policies. Therefore, access to accurate outbreak prediction models is essential to obtain insights into the likely spread and consequences of infectious diseases. The objective of this study is to predict the future COVID-19 situation of Korea. Here, we employed 5 models for this analysis; SEIR, local linear regression (LLR), negative binomial (NB) regression, segment Poisson, deep-learning based long short-term memory models (LSTM) and tree based gradient boosting machine (GBM). After prediction, model performance comparison was evelauated using relative mean squared errors (RMSE) for two sets of train (January 20, 2020-December 31, 2020 and January 20, 2020-January 31, 2021) and testing data (January 1, 2021-February 28, 2021 and February 1, 2021-February 28, 2021) . Except for segmented Poisson model, the other models predicted a decline in the daily confirmed cases in the country for the coming future. RMSE values' comparison showed that LLR, GBM, SEIR, NB, and LSTM respectively, performed well in the forecasting of the pandemic situation of the country. A good understanding of the epidemic dynamics would greatly enhance the control and prevention of COVID-19 and other infectious diseases. Therefore, with increasing daily confirmed cases since this year, these results could help in the pandemic response by informing decisions about planning, resource allocation, and decision concerning social distancing policies.

• Annals of Rehabilitation Medicine
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• v.42 no.6
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• pp.777-787
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• 2018

Objective To examine the long-term effects of the low-frequency repetitive transcranial magnetic stimulation (LF-rTMS) combined with task-specific training on paretic hand function following subacute stroke. Methods Sixteen participants were randomly selected and grouped into two: the experimental group (real LF-rTMS) and the control group (sham LF-rTMS). All the 16 participants were then taken through a 1-hour task-specific training of the paretic hand. The corticospinal excitability (motor evoke potential [MEP] amplitude) of the non-lesioned hemisphere, and the paretic hand performance (Wolf Motor Function Test total movement time [WMFT-TMT]) were evaluated at baseline, after the LF-rTMS, immediately after task-specific training, 1 and 2 weeks after the training. Results Groups comparisons showed a significant difference in the MEP after LF-rTMS and after the training. Compared to the baseline, the MEP of the experimental group significantly decreased after LF-rTMS and after the training and that effect was maintained for 2 weeks. Group comparisons showed significant difference in WMFT-TMT after the training. Only in the experimental group, the WMFT-TMT of the can lifting item significantly reduced compared to the baseline and the effect was sustained for 2 weeks. Conclusion The results of this study established that the improvement in paretic hand after task-specific training was enhanced by LF-rTMS and it persisted for at least 2 weeks.

• Korean Journal of Breeding Science
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• v.41 no.4
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• pp.391-396
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• 2009

Perilla frutescens, which belonging to the Labiatae family, is widely cultivated oil crop and have been used traditional herbal medicine in East Asia such as Korea, China, and Japan. Especially, the leaves and the seeds of this species are important in Korean traditional cooking, as one of the popular garnish and food colorants. Numerous studies have revealed that the beneficial health effects of perilla are due to its several phytochemicals contents, such as rosmarinic acid, caffeic acid, luteolin, and apigenin. For this reason, increasing the content of phytochemicals in perilla hasbecome a major breeding objective. The genetic diversity of the rosmarinic acid, caffeic acid, luteolin, and apigenin content in perilla seed is poorly documented. We analyzed the rosmarinic acid, caffeic acid, luteolin, and apigenin content of 203 accessions of perilla germplasm by high performance liquid chromatography (HPLC). The rosmarinic acid and luteolin contents ofgermplasms were ranged from $15.7{\mu}g/g$ to $2717.1{\mu}g/g$ and from $1.6{\mu}g/g$ to $582.4{\mu}g/g$ respectively.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.42 no.1
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• pp.143-150
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• 2019

We focus on the weapon target assignment and fire scheduling problem (WTAFSP) with the objective of minimizing the makespan, i.e., the latest completion time of a given set of firing operations. In this study, we assume that there are m available weapons to fire at n targets (> m). The artillery attack operation consists of two steps of sequential procedure : assignment of weapons to the targets; and scheduling firing operations against the targets that are assigned to each weapon. This problem is a combination of weapon target assignment problem (WTAP) and fire scheduling problem (FSP). To solve this problem, we define the problem with a mixed integer programming model. Then, we develop exact algorithms based on a dynamic programming technique. Also, we suggest how to find lower bounds and upper bounds to a given problem. To evaluate the performance of developed exact algorithms, computational experiments are performed on randomly generated problems. From the results, we can see suggested exact algorithm solves problems of a medium size within a reasonable amount of computation time. Also, the results show that the computation time required for suggested exact algorithm can be seen to increase rapidly as the problem size grows. We report the result with analysis and give directions for future research for this study. This study is meaningful in that it suggests an exact algorithm for a more realistic problem than existing researches. Also, this study can provide a basis for developing algorithms that can solve larger size problems.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.1
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• pp.137-143
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• 2019

Objective: The aim of this study was to compare male and female geese of two contrasting genotypes in terms of fatty acid composition, indexes related to human health, lipid metabolism and oxidative stability of the meat. Methods: The experiment was carried out on total of 120 geese of two different genotypes; the native breed Czech goose (CG) and commercial hybrid Novohradska goose (NG). One-d-old goslings were divided into 4 groups according to genotype and sex, and 8 birds from each group were slaughtered at 8 weeks of age. Results: The effects of the interactions between genotype and sex were observed on growth performance and carcass traits. Final body weight (p<0.001), daily weight gain (p<0.001), daily feed intake (p<0.001), slaughter weight (p<0.001), and cold carcass weight (p<0.001) were highest in NG males and lowest in CG females. The meat fatty acid composition results showed effects of both genotype and sex on the total n-6 and the total polyunsaturated fatty acid (PUFA) content, as well as the PUFA n-6/PUFA n-3 ratio. Regarding genotype, the total n-6, the total PUFA content and the PUFA n-6/PUFA n-3 ratio were higher in CG, and higher values were found in females. In terms of the lipid metabolism, ${\Delta}^5-{\Delta}^6$ desaturase (p = 0.006) was higher in males. The meat oxidative stability results revealed an interaction between genotype, sex and storage time (p<0.001). The highest (13.85 mg/kg) malondialdehyde content was measured in the meat of CG females after 5 days of storage and was presumably related to a higher PUFA content. Conclusion: NG had a relatively higher growth rate and meat oxidative stability, whereas the advantage of CG meat is its favourable fatty acid profile characterized by a higher PUFA content.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.13 no.7
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• pp.3412-3432
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• 2019

Recent advances in radio frequency (RF) power transfer provide a promising technology to power sensor nodes. Adoption of mobile chargers to replenish the nodes' energy has recently attracted a lot of attention and the mobility assisted energy replenishment provides predictable and sustained power service. In this paper, we study the joint optimization of mobile charging and data gathering in sensor networks. A wireless multi-functional vehicle (WMV) is employed and periodically moves along specified trajectories, charge the sensors and gather the sensed data via one-hop communication. The objective of this paper is to maximize the uplink throughput by optimally allocating the time for the downlink wireless energy transfer by the WMV and the uplink transmissions of different sensors. We consider two scenarios where the WMV moves in a straight line and around a circle. By time discretization, the optimization problem is formulated as a 0-1 programming problem. We obtain the upper and lower bounds of the problem by converting the original 0-1 programming problem into a linear programming problem and then obtain the optimal solution by using branch and bound algorithm. We further prove that the network throughput is independent of the WMV's velocity under certain conditions. Performance of our proposed algorithm is evaluated through extensive simulations. The results validate the correctness of our proposed theorems and demonstrate that our algorithm outperforms two baseline algorithms in achieved throughput under different settings.

• The Journal of the Korea Contents Association
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• v.19 no.7
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• pp.526-537
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• 2019

This study researched the effect of application systems for media industry by using machine learning method focusing on industrial organization theory. First, for applying the system successfully, formation of sympathy about needs is required. The introduction of machine learning can bring change in each stage of value chain especially, decision making process of investment and production process. In investment side, objective performance prediction data can enhance efficiency, and content diversity can decrease with concentrated investment phenomenon to secured content by the system. In production side, if the system support to make creators decrease simple repeat works, production efficiency will increase.

• Tuberculosis and Respiratory Diseases
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• v.82 no.3
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• pp.211-216
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• 2019

Background: Docetaxel is one of the standard treatments for advanced non-small cell lung cancer. Docetaxel is usually administered in a 3-week schedule, but there is significant toxicity. In this phase II clinical study, we investigated the efficacy and safety of a 4-weekly schedule of docetaxel monotherapy, as first-line chemotherapy for advanced squamous cell carcinoma in elderly lung cancer patients. Methods: Patients with stage IIIB/ IV lung squamous-cell carcinoma age 70 or older, that had not undergone cytotoxic chemotherapy were enrolled. Patients received docetaxel $25mg/m^2$ on days 1, 8, and 15, every 4 weeks. Primary endpoint was the objective response rate (ORR). Secondary endpoints were progression-free survival (PFS), overall survival (OS), and toxicity profiles. Results: A total of 19 patients were enrolled. Among 19 patients, 17 were for evaluated efficacy and safety. In the intent-to-treat population, ORR and disease control rate (DCR) were 11.8% and 47.1%, respectively. In the response evaluable population, ORR was 16.7% and DCR was 66.7%. Median PFS and OS were 3.1 months and 3.3 months, respectively. There were three adverse grade 3/4 events. Grade 1 neutropenia was reported in one patient. Conclusion: Our data failed to demonstrate efficacy of a 4-weekly docetaxel regimen, in elderly patients with a poor performance status. However, incidence of side effects, including neutropenia, was lower than with a 3-week docetaxel regimen, as previously reported.