• Composites Research
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• v.28 no.4
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• pp.204-211
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• 2015

This paper presents a theory related to a two-dimensional linear cross-sectional analysis, recovery relationship and a one-dimensional nonlinear beam analysis for composite wing structure with initial twist. Using VABS including a related theory, the design process of the composite rotor blade has been described. Cross-sectional analysis was performed at cutting point including all the details of geometry and material. Stiffness matrix and mass matrix were linked to each section to make 1D beam model. The 3D strain distributions within the structure were recovered based on the global behavior of the 1D beam analysis and visualize numerical results.

• Computational Structural Engineering
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• v.10 no.1
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• pp.185-191
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• 1997

Beam - and arch-like structures are two-dimensional bodies characterized by the fact of small thickness compared to the length of structures. Owing to this geometric feature, linear displacement approximations through the thickness such as Kirchhoff and Reissner-Mindlin theories which are more accessible one dimensional problems have been used. However, for accurate analysis of the behavior in the regions where the state of stresses is complex, two-dimensional linear elasicity or relatively high order of thickness polynomials is required. This paper analyses accuracy according to the order of thickness polynomials and introduces a technique for model combination for which several different polynomial orders are mixed in a single structure.

• Journal of Digital Contents Society
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• v.10 no.2
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• pp.367-373
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• 2009

Computer programming education helps students understand abstract concepts better and solve given problems independently. Many previous studies on programming education have focused on procedural programming languages such as BASIC and C, but studies on objected-oriented program ming language like JAVA is rare. This paper examines how an architectural neural, objected-oriented JAVA programming study system can improve logical thinking ability and encourage self-led study and stimulate interests in computers among elementary school students. The system has been developed and is suitable for distributed Internet environment. The experiment results demonstrated that the objected-oriented programming education enhances logical thinking ability, exerts a positive impact on student achievement in math and science, and stimulate interests in computers.

• Journal of The Korean Society of Agricultural Engineers
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• v.65 no.3
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• pp.1-13
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• 2023

Local governments play a critical role in achieving carbon neutrality and reducing national carbon emissions. To manage carbon emissions effectively, it is essential for local governments to analyze regional carbon emissions. In this study, we developed a model for estimating carbon emissions based on land use and analyzed regional characteristics of carbon emissions to suggest policies for achieving carbon neutrality at the regional level. Our model for calculating carbon emissions is based on an analysis of the activities that contribute to carbon emissions for each land use, and we established the spatial scope of carbon emission calculation. We applied this model to the cities and counties in Gyeongsangnam province, calculating carbon emissions from settlement and agricultural production activities and comparing regional characteristics of carbon emissions. Our analysis showed that areas with larger populations generally produced higher emissions in all categories, but we observed different results in terms of unit emissions, emissions divided by area, population, and household. Based on these findings, we propose policies such as increasing the generation of new and renewable energy using public institutions, promoting the conversion to cleaner cooking and heating energy sources, and encouraging the adoption of eco-friendly automobiles on roads. We believe that our analysis of the spatial and regional characteristics of carbon emissions can help local governments establish effective policies for reducing carbon emissions in their regions.

• Composites Research
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• v.22 no.5
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• pp.24-29
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• 2009

In this paper, a post-tensioned reinforced concrete slab was analyzed by the specially orthotropic laminates theory. Both the geometrical and material property of the cross section of the slab was considered symmetrically with respect to the neutral surface so that the bending extension coupling stiffness, $B_{ij}=0$, and $D_{16}=D_{26}=0$. Reinforced concrete slab behave as specially orthotropic plates. In general, the analytical solution for such complex systems is very difficult to obtain. Thus, finite difference method was used for analysis of the problem. In this paper, the finite difference method and the beam theory were used for analysis. The result of beam analysis was modified to obtain the solution of the plate analysis.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2021.11a
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• pp.27-28
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• 2021

The search for new corrosion inhibitors for different corrosive mediums is a never-ending task. In the present work, the corrosion inhibition behavior and adsorption mechanism of two novel synthetic thiazolidinedione derivatives noted MTZD and ATZD in 3.5 wt.% NaCl solution on copper were investigated. Electrochemical, scanning electron microscope (SEM), atomic force microscopy (AFM) techniques were used along with first-principles DFT calculations. At maximum inhibitor concentration i.e., 300 ppm corrosion inhibition efficiency reached maximum up to 90% and 96% for MTZD and ATZD, respectively, and thereby followed the order of ATZD > MTZD. The inhibition efficiency increased up to 24 h of immersion, and then decreased after 48h immersion. The potentiodynamic curves suggested that the inhibition action of tested compounds is a mixed type of inhibitor. The first-principles DFT calculations suggested that compounds under investigation formed covalent bonds with Cu(111) surface via reactive sites. SEM and AFM results confirmed the formation of protective barrier that prevent corrosion attack.

• Journal of the Korea institute for structural maintenance and inspection
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• v.11 no.3
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• pp.143-150
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• 2007

Six full scale column specimens have been tested under the constant axial and cyclic lateral load. An equivalent stress block parameter was used to estimate flexural capacity of columns confined by carbon sheet tube. Through the non-linear regression analysis, behaviors of CFCST(Concrete Filled Carbon Sheet Tube) columns under the cyclic lateral load were estimated and compared with test results.

• Land and Housing Review
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• v.15 no.3
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• pp.189-198
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• 2024

This study analyzes the thermal performance of insulating concrete based on material combinations aimed at carbon reduction. The study compares the thermal and structural properties of insulating concrete enhanced with perlite and EPS (Expanded Polystyrene) beads to conventional concrete, with a focus on the impact of insulation properties on thermal conductivity. The results indicate that the content of EPS beads is critical to the insulating performance, and increased moisture absorption significantly reduces the energy efficiency of the insulating concrete. These findings provide valuable insights for the design and application of insulating concrete to enhance energy efficiency and reduce carbon emissions. This study offers guidance for further developing insulating concrete as a carbon-reducing building material.

• Cartoon and Animation Studies
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• s.50
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• pp.1-22
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• 2018

This study investigated realism sceneries shown in animation movies of auteurism. Although animation has properties of mechanical images arranged by short cuts, it essentially starts with the images dealing with space art based on the consciousness of an author. In this aspect, sceneries of animation movies can be the most proper subject for study from the viewpoint of image. Generally, sceneries of animation movies maintain the neutral position as a stage setting for story. However, as for auteurism animation, the sceneries have subjective meaning as major media to express the work or the vision and value of the author on the world. The representative animation movies that reflect the role and meaning of realism sceneries among auteurism animations are and . The former shows Korean sceneries and the latter presents local sceneries of Japan quite well. Reviewing the characteristics of sceneries shown in two movies, the sceneries of are the discovery of internal consciousness of the author that signifies pure innocence of childhood into the voice of nature through the style of the author. Meanwhile, sceneries of adopted nature landscape surrealistically based on the internal consciousness of the author and described the forest as the absolute utopia of the author. As such, the sceneries shown in two movies were utilized as the "framework of thought" of the authors that intensify the viewpoint of the movies on the world through empirical interpretation and detailed description of neutral landscape based on internal consciousness of the authors.

• Korean journal of communication and information
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• v.38
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• pp.183-210
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• 2007

The study tried to explore ordinary people's press fairness concept being neglected by the mainstream of fairness research thus far. With empirical standpoint, this study first investigated (un)fairness concept held by general audience, and then compared it with existing ones long suggested by experts such as scholars and media workers. Also, the study examined audience's concept construct in terms of its characteristics and implications. A systematic sample of 300 adults in Seoul was interviewed and their answers (instances of press unfairness) were analyzed and categorized. The most serious problem in fairness, they pointed, was that the press's not neutral. Also, truth and balance were importantly raised as a press problem with regard to fairness. The result showed press ethics and commercial morals could be a significant element for people's view on press fairness. These elements are new to the literature and heuristic regarding how to approach toward fairness issue in our society. The study also discusses the implications of other findings.