• Kyungpook Mathematical Journal
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• v.61 no.3
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• pp.591-612
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• 2021

In this paper, a uniformly convergent numerical scheme is designed for solving singularly perturbed reaction-diffusion problems. The problem is converted to an equivalent weak form and then a Galerkin finite element method is used on a piecewise uniform Shishkin mesh with linear basis functions. The convergence of the developed scheme is proved and it is shown to be almost fourth order uniformly convergent in the maximum norm. To exhibit the applicability of the scheme, model examples are considered and solved for different values of a singular perturbation parameter ε and mesh elements. The proposed scheme approximates the exact solution very well.

• International journal of advanced smart convergence
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• v.9 no.4
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• pp.101-105
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• 2020

In this study, we are going to discuss the role of sound, which exists as the background of a movie scene, and the relationship between seeing and hearing. In order to analyze the form in which the scene and sound are matched, the visual content of the image must be analyzed first. In this study, we analyzed Stanley Kubrick's film . Generally, there are both visual and auditory features in the scene of the movie. In some cases, the sound is emphasized more than the scene, and the scene is emphasized more than the sound. In particular, the sound in movies enables a wider imagination and a three-dimensional experience. Images and sounds will have different meanings and effects depending on the purpose of use. By analyzing the correlation between visual scene and auditory sound based on the role sound plays in the film in this study, we would like to confirm that sound is one essential element that has the role of equivalent and independent expression, not the role of assisting images.

• Journal of the Korean Society of Industry Convergence
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• v.24 no.4_1
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• pp.411-419
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• 2021

In this study, IGBT_Total_Loss and DIODE_Total_Loss were used to analyze the slope of the junction temperature for each section for temperature and duty variables in order to simply calculate the junction temperature of the power semiconductor (IGBT). As a result of the calculation, IGBT_Max_Junction_Temp and DIODE_Max_Junction_Temp form a proportional relationship with temperature for each duty. This simulation data shows that the power loss of a power semiconductor is calculated in a complex manner according to the current dependence index, voltage dependence index, and temperature coefficient. By applying the slope for each condition and section, the junction temperature of the power semiconductor can be calculated simply.

• 중국학논총
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• no.70
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• pp.19-37
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• 2021

Foreign learners are not focusing on "적" grammar. Therefore, the lack of materials on "적" is the reason that foreign learners use "적" in real life. In particular, when teaching the Chinese-dependent noun "적", there are some problems in making the Chinese equivalent of "적". more accurately understood by Koreans. In addition, when using grammar through analyzing the grammatical conjunction centered on "적" and the corresponding expression of Chinese, the main reason for the error is that there is no common concept and form in the mother tongue, so there is no consciousness. Therefore, it is difficult for learners to learn similar expressions that are not in Chinese or Korean. Therefore, this study aims to improve specific educational programs for Korean learners and Korean Chinese learners in terms of the time system and the corresponding performance of Chinese grammar and Chinese characters based on the previous version of "적".

• Advances in Computational Design
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• v.8 no.1
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• pp.77-96
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• 2023

Calculating size-dependent mechanical properties of the nano-scale materials usually involves cumbersome numerical and theoretical works. In this paper, we aim to present a closed-form relation to calculate the length-dependent Young's modulus of carbon nanotubes (CNTs) based on nonlocal elasticity theory. In this regard, a single wall carbon nanotube (SWCNT) is considered as a rod structure and the governing nonlocal equations are developed under uniaxial tensile load. The equations are solved using analytical methods and strain distribution, total displacement and the size-dependent equivalent Young's modulus are obtained. Further, the results are compared with the molecular dynamics results from the literature. The outcome indicates that the calculated relations are coincident with the molecular dynamics results.

• Journal of Information Processing Systems
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• v.19 no.2
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• pp.164-172
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• 2023

Through theoretical proof and algorithm design, this paper numerically demonstrates that the three sampling methods of DDS are equivalent in amplitude-frequency characteristics. Depending on theoretical analysis, the article obtains the conclusion that 2 points are optimal when sampling at 2, 3, and 4 points. Built on the data results, this paper obtains the fractional form of the amplitude and phase of the DDS sampled signal; in addition, this paper also obtains the design parameters of the DDS post-stage filter. It also gives a control method for the calculation error when addressing this issue.

• The Journal of Economics, Marketing and Management
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• v.6 no.2
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• pp.29-33
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• 2018

Purpose - This study aims to offer the suggestions for the researches and policies that could be used as important data to effectuate future FTA. The objective of this study is to suggest a direction of Korea that can form a new logistics hub in Northeast Asia. Research design, data, and methodology - This study was conducted in parallel with literature review and empirical studies for the analysis. 180 valid samples were collected from Korean consumers', and qualitative analysis was employed on the satisfaction level of imported goods welfare of Korean consumers. Results - It is expected that Korea and China would experience increased opportunity factors in this area with the growth of economic sphere in Northeast Asian. If existing problems are solved by utilizing regional environment efficiently together, the hub function of Northeast Asia logistics will be advanced. Conclusions - Korea is introducing and operating special economic zones that provide the exception and support for foreign investment. Therefore, it is necessary to monitor the prices of imported goods, so that the exporters can adjust the prices and obtain the unjust profit equivalent to the tariff reduction by grasping the overseas market trends of the imported product prices.

• Journal of the Korean Institute of Telematics and Electronics
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• v.5 no.4
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• pp.9-19
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• 1968

In this paper, I introduced the theoretical formulas for calcuating the input impedance of a folded dipole antenna which is held in parallel with the conductive supporter. Through the comparision of the above impedance formulas with the imput impedance formulas of a half wave dipole antenna which is parallel to the conductive supporter, it was found that the former can be made in identically same form as the latter, if some conditions are satisfied. The equivalent conditions mentioned above are derived also and the manufacturing of a vertically polarized omni-drectional antenna is apossible by the use of above equivalent conditions, because a half wave dipole antenna in parallel with a conductive supporter is already illustrated to become an omni-directional vertical polarization antenna. Some experimental data are shown together.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.8
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• pp.4083-4088
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• 2016

Background: Physical inactivity has been identified as the fourth leading risk factor for global mortality and is associated with increased breast cancer diagnosis and recurrence. Purpose: To examine the association between adult lifetime physical activity and breast cancer risk in a case-control analysis. Materials and Methods: This study involved 122 cases of breast cancer and 121 controls in the state of Kelantan in Malaysia. A comprehensive measure of lifetime physical activity was used to assess occupational, household, and recreational/sports activity. For every type of activity, a metabolic equivalent (MET) score was assigned using the compendium of physical activities. MET-hours/week per year for all types of activities at different levels of intensities for different age groups were calculated. Logistic regression analysis was used to estimate odds ratios between various measures of physical activity and breast cancer risk. Conclusions: The mean MET-hours/week per year for all activities were 120.0 and 132.9 of MET-hours/week per year for cases and controls respectively. Household activities accounted for about 70% of the total lifetime physical activities. Only about 2.5% of the total lifetime physical activities were in the form of recreational/sports. This study found no association between lifetime occupational and recreational/sports physical activities with breast cancer risk among Kelantanese women. However, higher intensity lifetime household activities seemed to significantly reduce risk of breast cancer.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.34-34
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• 2017

Various extracts of roots, stems, and leaves of Phalaenopsis Sogo Yukidian 'V3' were evaluated for total phenolics, total flavonoids, and antioxidant capacity. The conjugate form of stem samples contained the highest total phenolics ($5.092{\pm}0.739mg$ gallic acid equivalent per g dry weight） and the highest total flavonoids ($2.218{\pm}0.021mg$ rutin equivalent per g dry weight) was found in the hexane extract of leaves. The ethyl acetate extract of roots showed the maximum antioxidant activity as compared to other extracts. Of which, the $IC_{50}$ value of this sample were 0.070 mg/mL and 0.450 mg/mL in the 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging assay and reducing power, respectively, while the lipid peroxidation inhibition (LPI) value was as 94.2% by ${\beta}$-carotene bleaching method. Five phenolic compounds including caffeic acid, syringic acid, vanillin, ellagic acid, and cinnamic acid were quantified by high-performance liquid chromatography (HPLC). It is suggested that roots of the hybrid Phalaenopsis Sogo Yukidian 'V3' can be explodited as an effective source of antioxidants.