• Structural Engineering and Mechanics
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• 제86권1호
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• pp.93-107
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• 2023

In this paper, a density based topology optimization is proposed for generating of supports required in additive manufacturing to maintain the overhanging regions of main structures during layer by layer fabrication process. For this purpose, isogeometric analysis method is employed to model geometry and structural analysis of main and support structures. In order to model the problem two cases are investigated. In the first case, design domain of supports can easily be separated from the main structure by using distinct isogeometric patches. The second case happens when the main structure itself is optimized by using topology optimization and the supports should be designed in the voids of optimum layout. In this case, in order to avoid boundary identification and re-meshing process for separating design domain of supports from main structure, a parameterization technique is proposed to identify the design domain of supports. To achieve this, two density functions are defined over the entire domain to describe the main structure and supporting areas. On the other hand, since supports are under gravity loads while main structure and its stiffness is not completed during manufacturing process, in the proposed method, stiffness of the main structure is considered to be trivial and the gravity loads are also naturally applied to design support structures. By doing so, the results show reasonable supports are created to protect, continuously, overhanging surfaces of the main structure. Several examples are presented to demonstrate the efficiency of the proposed method and compare the results with literature.

• 농촌지도와개발
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• 제26권3호
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• pp.127-141
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• 2019

Self-esteem and social supports are important variable influencing adjustment to college life. This study aims to identify the factors influencing adjustment to college life. Data were collected from 265 usable questionnaires among college students in Pyeongtek University. Results of a factor analysis yielded three dimensions of self-esteem which were talent/attitude and capacity/pride. And results of factor analysis also yielded three dimensions of social supports which were family, friends, and professor supports. Hierarchical regression analysis revealed that capacity/pride and all of social support factors affected significantly for adjustment to college life. And female and aptitude for students' major had a positive affect on adjustment to college life. It was suggested that self-esteem, social supports, and aptitude for students' major should be considered in college management policy.

• 농촌지도와개발
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• 제28권4호
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• pp.175-190
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• 2021

Self-efficacy and social supports are important variable influencing adjustment to college life. This study aims to identify the factors influencing adjustment to college life. Data were collected from 265 usable questionnaires among college students in Pyeongtek University. Results of a factor analysis yielded three dimensions of self-efficacy which were ability to start promotion/ social ability/ ability to carry out activities/ability to overcome hate experiences/ social sustainability. And results of factor analysis also yielded three dimensions of social supports which were family, friends, and professor supports. Hierarchical regression analysis revealed that social ability/ ability to carry out activities/ability to overcome hate experiences and all of social support factors affected significantly for adjustment to college life. And female and attitude for students' major had a positive affect on adjustment to college life. Results suggested that self-efficacy, social supports, and aptitude for students' major should be considered in college management policy.

• 가족자원경영과 정책
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• 제9권2호
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• pp.1-21
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• 2005

The purpose of this study was to analyze the effect of the influencing factors on the economic and educational supports selection of small self-employed business. A sample of 321 was selected from self-employed workers living in Daegu. For data analysis, logistic regression was used. The major findings were as follows: 1 The determinants of the economic supports selection in self-employed business were father's working experiences in self-employed business, taking employees or not in business, having housing ownership or not, and as well as the amount of starting capital. 2. The determinants of the educational supports selection in self-employed business were self-employer's working experience as self-employed before or not, and empowerment with self-employed work.

• 대한수학회논문집
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• 제18권2호
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• pp.385-392
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• 2003

The sum Of L - R fuzzy numbers With Unbounded Supports based on Archimedean continuous f-norm T is considered. Results are more simple than those of the case for bounded supports.

• 한국분말재료학회지
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• 제24권2호
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• pp.96-101
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• 2017

Well-dispersed platinum catalysts on ruthenium oxide nanofiber supports are fabricated using electrospinning, post-calcination, and reduction methods. To obtain the well-dispersed platinum catalysts, the surface of the nanofiber supports is modified using post-calcination. The structures, morphologies, crystal structures, chemical bonding energies, and electrochemical performance of the catalysts are investigated. The optimized catalysts show well-dispersed platinum nanoparticles (1-2 nm) on the nanofiber supports as well as a uniform network structure. In particular, the well-dispersed platinum catalysts on the ruthenium oxide nanofiber supports display excellent catalytic activity for oxygen reduction reactions with a half-wave potential ($E_{1/2}$) of 0.57 V and outstanding long-term stability after 2000 cycles, resulting in a lower $E_{1/2}$ potential degradation of 19 mV. The enhanced electrochemical performance for oxygen reduction reactions results from the well-dispersed platinum catalysts and unique nanofiber supports.

• 한국지구물리탐사학회:학술대회논문집
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• 한국지구물리탐사학회 2003년도 Proceedings of the international symposium on the fusion technology
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• pp.103-108
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• 2003

In the construction of mountain tunnels, reaction forces of the legs of steel arch supports against the ground are often expected to support the ground being excavated. In these cases, a stress concentration occurs in the ground directly under the support legs. If the bearing capacity of the ground is insufficient or displacement is not effectively constrained, the local failure of the ground under the support legs or settlement of the tunnel supports due to large deformation could result. It is therefore necessary to reinforce the support legs to reduce settlement. As a means of reducing settlement, wing-ribbed steel arch supports are well used. In this study, with the aim of finding a way to quickly reduce the settlement of steel arch support legs, effectiveness of a new type of wing ribs to reinforce steel arch supports was investigated through laboratory testing.

• 보건교육건강증진학회지
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• 제24권4호
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• pp.161-179
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• 2007

To commonly apply the ${\ulcorner}$Measurement parameter for housewives for rearing-related supports of a husband${\lrcorner}$ in Korea and Japan, the current study conducted to confirm the relationship between recognition of a housewife for rearing-related supports of a husband and mental health after reviewing the appropriateness of the parameter. For the statistical analysis, 829 married Korean women in D city and 1,302 Japanese women in S city having children before entering a school were subjected for the study. For reviewing the appropriateness of the parameter, the simultaneous factor analysis that adopted the structural equation modeling was used. As the result of the analysis, 10 categories of factor structural model comprising the ${\ulcorner}$Recognition of a housewife for rearing-related supports of a husband${\lrcorner}$ resulted with the secondary model which sets of ${\ulcorner}$Recognition for emotional support${\lrcorner}$, ${\ulcorner}$Recognition for instrumental support${\lrcorner}$ and ${\ulcorner}$Recognition for information support${\lrcorner}$ as the primary factor and ${\ulcorner}$Recognition of a housewife for rearing-related supports of a husband${\lrcorner}$ as the secondary factor, and the model was found to be appropriate for the data in Korea and Japan. The result is considered to prove the constructs validity of ${\ulcorner}$Recognition of a housewife for rearing-related supports of a husband${\lrcorner}$ parameter. In addition, the relationship between ${\ulcorner}$Recognition of a housewife for rearing-related supports of a husband${\lrcorner}$ and mental health(GHQ) was reviewed by using multiple indicator model, and found the similarity of Korean and Japanese data. The scores measured by using the above parameter resulted to show high relationship with educational level of housewife, family configuration, and number of children.

• 한국안전학회지
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• 제30권5호
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• pp.37-43
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• 2015

This study examined the effects of the minimum horizontal load on the structural behaviors and safety of system supports. The minimum horizontal load was frequently ignored in the design of system supports even though the level of that load was specified in the code and guide in Korea such as 'Standard Specification in Temporary Construction' and 'Guide to Installation of Shores for a Concrete Bridge'. To examine the effects of considering the minimum horizontal load, the finite element analysis were performed for various system supports. By varying installing parameters of system supports such as the vertical member spacing, the installation height, and the thickness of slab, the maximum combined stress ratios were estimated to investigate the structural safety of system supports. The results showed similar axial stress in vertical members but an increase in bending stress with a consideration of the horizontal load. The combines stress ratios are remarkably increased due to the consideration of the horizontal load. Consequently, the system supports, which were initially estimated to be safe when only the vertical loads were considered, were changed to be unsafe in most cases by the effects of the both the vertical and horizontal stresses. Therefore, the minimum horizontal load following the code and the guide is an essential load that could control the structural safety of system supports.

• 공학교육연구
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• 제16권6호
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• pp.29-37
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• 2013

The necessity of convergence education is more emphasized based on the education policy for fostering creative men of talent. Inside universities, however, programs for training talented individuals are still at primary stage. Universities understanding the importance of convergence education and thus founding some major fields of convergence studies have experienced hosts of troubles. The paper discusses the necessary plans of supports from the government and the university to activate the convergence education in accord with the social demands. Twenty-eight professors in engineering colleges participated in the survey for reviewing the required factors for the convergence education. In addition, structured interviews were carried out with three specialists working in industry and academic area of convergence technology. The study could suggest the following activation plans based on the government supports: (1) establishing a support center of convergence education, (2) founding a major field of convergence, (3) developing curriculums and curriculum subjects, and (4) hosting related conferences and forums. Also, the study could suggest the following activation plans based on the university supports: (1) developing special programs on convergence education in accord with the industrial demands, (2) revising regulations and administrative systems more flexible for the convergence education, and (3) providing incentives to the participants in the convergence education.