• Proceedings of the KIEE Conference
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• 1987.11a
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• pp.33-36
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• 1987

Is this study it is proposed a method which is able to compute preciously using time-difference method to the air-gap magnetic field in electric machines take into account of eddy current induced. The air-gap magnetic field has slot harmonics which are due to the structure of machines and the shape of slot harmonics varies with the related positions of slots when the rotor moves. Accordingly, considering the influence of slot-harmonics, we coupled macro-air-gap element with first-order triangular elements in domain and used direct-convergence method for magnetic saturation.

• Korean Institute of Interior Design Journal
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• v.22 no.6
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• pp.3-10
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• 2013

This study intends to clarify the key elements of designing low energy residential building construction by planning out residential construction in nature oriented designing method utilizing nearby environment and nature oriented energy from designing stage instead of construction of low energy residential building. Development of building technology is proportional to the development of technology that lasts already. However, what is no less important than the advancement of technology, it is the study of fundamental phenomena energy use in response to climate, reduction, such as recycling. It is possible in such a purpose, it is assumed that there is a need to study elements implementation plan in accordance with the climatic characteristics of the study. Method for controlling the condition solar radiation, sunshine, depending on the characteristics of the weather, by utilizing the convection phenomenon of nature, to maintain the air comfort in the interior space is the essence of eco-friendly construction and passive Property This is an important architectural elements to be aim. For through the analysis of this case, corresponding to the phenomenon of the features of the macro climate and micro climate due to climate change, a combination building blocks of classification placement of each, shape, structure, elevation, space, of the material appeared in various it was possible to know the construction characteristics were. As shown in each case, construction method to address climate change has been found to apply to a comprehensive analysis climatic characteristics of each region, in response to this, the construction of element each corresponding.

• Korean Journal of Materials Research
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• v.25 no.8
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• pp.370-375
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• 2015

In this study, to confirm the effect of alloying elements on the phase transformation and conditions of the friction stir process, we processed two materials, SS400 and SM45C steels, by a friction stir process (FSP) under various conditions. We analyzed the mechanical properties and microstructure of the friction stir processed zone of SS400 and SM45C steels processed under 400RPM - 100mm/min conditions. We detected no macro (tunnel defect) or micro (void, micro crack) defects in the specimens. The grain refinement in the specimens occurred by dynamic recrystallization and stirring. The microstructure at the friction stir processed zone of the SS400 specimen consisted of an ${\alpha}$-phase. On the other hand, the microstructure at the friction stir processed zone of the SM45 specimen consisted of an ${\alpha}$-phase, $Fe_3C$ and martensite due to a high cooling rate and high carbon content. Furthermore, the hardness and impact absorption energy of the friction stir processed zone were higher than those of base metals. The hardness and impact absorption energy of FSPed SM45C were higher than that of FSPed SS400. Our results confirmed the effect of alloying elements on the phase transformation and mechanical properties of the friction stir processed zone.

• Computers and Concrete
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• v.24 no.3
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• pp.207-222
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• 2019

This paper has presented an effective and accurate meso-scale finite element model for simulating the fracture process of concrete under compression-shear loading. In the proposed model, concrete is parted into four important phases: aggregates, cement matrix, interfacial transition zone (ITZ), and the initial defects. Aggregate particles were modelled as randomly distributed polygons with a varying size according to the sieve curve developed by Fuller and Thompson. With regard to initial defects, only voids are considered. Cohesive elements with zero thickness are inserted into the initial mesh of cement matrix and along the interface between aggregate and cement matrix to simulate the cracking process of concrete. The constitutive model provided by ABAQUS is modified based on Wang's experiment and used to describe the failure behaviour of cohesive elements. User defined programs for aggregate delivery, cohesive element insertion and modified facture constitutive model are developed based on Python language, and embedded into the commercial FEM package ABAQUS. The effectiveness and accuracy of the proposed model are firstly identified by comparing the numerical results with the experimental ones, and then it is used to investigate the effect of meso-structure on the macro behavior of concrete. The shear strength of concrete under different pressures is also involved in this study, which could provide a reference for the macroscopic simulation of concrete component under shear force.

• International Journal of Computer Science & Network Security
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• v.22 no.2
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• pp.318-326
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• 2022

Marketing stress testing is a new method of identifying the company's strengths and weaknesses in a turbulent environment. Technically, this is a complex procedure, so it involves artificial intelligence and machine learning. The main problem is currently the development of methodological approaches to the development of the company's digital model, which will provide a framework for machine learning. The aim of the study was to identify and develop an author's approach to the parameterization of the company's business processes for machine learning-based marketing stress testing. This aim provided the company's activities to be considered as a set of elements (business processes, products) and factors that affect them (marketing environment). The article proposes an author's approach to the parameterization of the company's business processes for machine learning-based marketing stress testing. The proposed approach includes four main elements that are subject to parameterization: elements of the company's internal environment, factors of the marketing environment, the company' core competency and factors impacting the company. Matrices for evaluating the results of the work of expert groups to determine the degree of influence of the marketing environment factors were developed. It is proposed to distinguish between mega-level, macro-level, meso-level and micro-level factors depending on the degree of impact on the company. The methodological limitation of the study is that it involves the modelling method as the only one possible at this stage of the study. The implementation limitation is that the proposed approach can only be used if the company plans to use machine learning for marketing stress testing.

• Journal of Korea Foundry Society
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• v.37 no.5
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• pp.148-156
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• 2017

The effects of minor additives on the casting properties of AC4A aluminum alloys were investigated. Measurements of the cooling curve and microstructure observations were conducted to analyze the effects of Ti-B and Sr minor elements during the solidification process. A fine grain size and an increase in the crystallization temperature for the ${\alpha}-Al$ solution were evident after the addition of 0.1wt% Al-5%Ti-1%B additive. The modification effect of the eutectic $Mg_2Si$ phase with the addition of 0.05% Al-10%Sr additive was prominent. A fine eutectic $Mg_2Si$ phase and a decrease in the growth temperature of the eutectic $Mg_2Si$ phase were evident. Fluidity, shrinkage and solidification-cracking tests were conducted to evaluate the castability of the alloy. The combined addition of Al-5%Ti-1%B and Al-10%Sr additives showed the maximum filling length owing to the effect of the fine ${\alpha}-Al$ grains. The macro-shrinkage ratio increased, while the micro-shrinkage ratio decreased with the combined addition of Al-5%Ti-1%B and Al-10%Sr additives. The macro-shrinkage ratio was nearly identical, while the micro-shrinkage ratio increased with the addition of the Al-10%Sr additive. The tendency of the occurrence of solidification cracking decreased owing to the effect of the fine ${\alpha}-Al$ grains and the modification of the $Mg_2Si$ phase with the combined addition of Al-5%Ti-1%B and Al-10%Sr additives.

• Communications of Mathematical Education
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• v.23 no.3
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• pp.849-862
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• 2009

The goal of this study is to present essential methods of minimalizing Korean populism in our society through the investigation of relations between populism and mathematical education which people don't easily recognize. We made a thorough analysis on the populism-generating elements and then presented mathematical methods which could convert micro-way of thinking into macro-one. We believe that an explicit investigation of the relations between Korean populism and mathematical education and the ensuing appropriate role-setting of mathematical education would help secure an essential solution for minimalizing populism in our society.

• Journal of Digital Convergence
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• v.17 no.9
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• pp.337-342
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• 2019

This study is a study on the factors of preference for mobile game characters whose intellectual property rights (IP) influence is great. There have been many cases in which user-side research has been conducted on the character's preference factors. However, it is largely macro-divided. Detailed analytical studies are needed because details are overlooked. By classifying the elements of the character, the five-point scale of the recorder also obtains the data through the survey. Detailed factors were analyzed according to the results. Prior studies and results were compared and factors consistent with prior studies were analyzed. Because this study analyzed detailed factors, unlike previous studies of macro view. It is expected to help develop characters in the future.

• Composites Research
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• v.34 no.1
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• pp.70-75
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• 2021

This paper presents a novel algorithm to reconstruct meso-scale representative volume elements (RVE), referring to experimentally observed features of Sheet Molding Compound (SMC) composites. Predicting anisotropic mechanical properties of SMC composites is challenging in the multiscale virtual test using finite element (FE) models. To this end, an SMC RVE modeler consisting of a series of image processing techniques, the novel reconstruction algorithm, and a FE mesh generator for the SMC composites are developed. First, micro-CT image processing is conducted to estimate probabilistic distributions of two critical features, such as fiber chip orientation and distribution that are highly related to mechanical performance. Second, a reconstruction algorithm for 3D fiber chip packing is developed in consideration of the overlapping effect between fiber chips. Third, the macro-scale behavior of the SMC is predicted by the multiscale analysis.

• Korean Journal of School Psychology
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• v.17 no.1
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• pp.125-144
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• 2020

Only a few studies have investigated the influence of career calling on career adaptability and the mechanisms behind this relationship, so this investigated how the search for and presence of meaning, the two elements of meaning in life, affect this relationship. 247 Participants completed a survey on career calling, career adaptability, the search for meaning and the presence of meaning. Correlational analysis was conducted to examine the relationships between the research variables. A serial multiple mdediating effects test was conducted to test the proposed mediating effects. Finally, a bootstrapping procedure was used with SPSS Macro to test the significance of the indirect effects. The results were as follows: First, career calling was positively related with career adaptability. Second, the search for and presence of meaning both partially mediated the relationship between career calling and career adaptability. This result implies that the search for meaning alone can lead to positive outcomes, such as increasing career adaptability, a result not found in previous studies. Third, the relationship between career calling and career adaptability was sequentially mediated by the search for meaning and the presence of meaning. This paper ends with a discussion of implications of this study's results in clinical practice and this study's limitations.