• International Journal of Naval Architecture and Ocean Engineering
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• v.9 no.2
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• pp.185-198
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• 2017

The application of composites as an alternative material for marine steel hatch covers is the subject of this study. Two separate approaches are considered; weight reduction approach and strengthening approach. For both approaches Finite Element Analysis (FEA) was performed using ANSYS software. Critical design parameters of the composite hatch cover and FEA are discussed in details. Regarding the weight reduction approach; steel hatch covers of a bulk carrier were replaced by composite covers and a weight reduction of 44.32% was achieved leading to many benefits including fuel saving, Deadweight Increment and lower center of gravity of the vessel. For the strengthening approach; the foremost hatch cover was strengthened to withstand 150% of the load required by IACS for safer navigation while no change in weight was made between the steel and composite covers. Results show that both approaches are feasible and advantageous.

• Bulletin of the Korean Mathematical Society
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• v.51 no.4
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• pp.1015-1022
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• 2014

This paper continues the investigation of covers of cyclic acts over monoids. Special attention is paid to (P)-covers and strongly flat covers of cyclic acts. In 2008 Mahmoudi and Renshaw posed some open problems and we gave some examples on them in 2012. In this paper, we obtained some further results on these problems and hence gave some deeper answers to them.

• Journal of the Korean Mathematical Society
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• v.49 no.1
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• pp.1-16
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• 2012

In the present paper we describe a class of Gorenstein, finite and at morphism ${\varrho}$: $X{\rightarrow}Y$ of degree 6 of algebraic varieties, called Anglo-American covers. We prove a general Bertini theorem for them and we give some evidence that the cover ${\varrho}$: $A{\rightarrow}\mathbb{P}_k^2$ associated general (1, 3)-polarized abelian surface is Anglo-American.

• Transactions of the Korean Society of Automotive Engineers
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• v.25 no.3
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• pp.267-272
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• 2017

Automotive seat covers with olefin film imported from foreign companies exhibit some problems such as low peeling strength and high burning rate. The traditional manufacturing process requires gas flame or direct heating for the laminating step. This paper introduces an alternative solution that replaces the olefin film and flame lamination method in making automotive seat covers or interior fabrics. We adopt a new manufacturing concept that applies a water-based resin coating to develop a coating system. The coating machine was successfully developed and tested. Results are intended to contribute to improving the quality and productivity of automotive seat cover production.

• Communications of the Korean Mathematical Society
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• v.11 no.2
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• pp.285-294
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• 1996

In this paper, we show relations between injective covers and direct sums, some commutative properties, and composition properties in the injective covers.

• International Journal of Reliability and Applications
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• v.5 no.4
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• pp.147-154
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• 2004

This work developed and algorithm for a set covering model when the reliability of covers is a concern. This model extended the usage of the set covering model.

• Fire Science and Engineering
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• v.20 no.3 s.63
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• pp.35-41
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• 2006

In this study, we presented the problems in the insulation cover of 22.9kV transformer bushing through investigating actual conditions. After thermal stress applied to the insulation cover, deterioration patterns, thermogravimetric and infrared characteristics were analyzed, and the results were applied to the cause analysis of accidents and judgement of safety. The insulation covers are used to protect exposed terminals of transformer, but they had improper size and length. Therefore, they could not show efficient insulation function. In case that thermal stress of $150^{\circ}C$ was applied to the insulation covers, plastic insulation covers(A, B, D, E) damaged severely, whereas rubber insulation cover(C) showed normal shapes. In the result of thermogravimetric analysis, the thermal gravity of plastic covers(A) decreased about 33.3% at $307.8^{\circ}C\;to\;405.9^{\circ}C$. and he thermal gravity of rubber covers (C) decreased about 53.7% at $258.8^{\circ}C\;to\;32.9^{\circ}C$. In the result of FT-IR analysis, plastic covers showed peaks characteristic of $CH_2,\;CH_3$, C=O and C=C bonds, whereas rubber covers showed peaks characteristic of OH, $CH_2,\;CH_3$, C=O, C=N and C=C bonds.

• Archives of design research
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• v.19 no.3 s.65
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• pp.167-182
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• 2006

From 1998 Seoul city is being rebuilt for 'the city which people want to go around on foot'. Many streets only for cars have been transformed for pedestrians. In addition to that streets are built not only just to pass by, but also enjoy themselves, so 8 Streets in Seoul have been redecorated as 'Streets of History and Culture'. These Streets are chosen because they have their own unique history or culture, so they are remodeled with lightings, exhibition pavilions or sign postings etc except manhole covers. Even these 8 streets have manhole covers; they are not particular, just same as like other streets. For most streets manhole cover is an essential component of them, but it is mostly omitted to be designed in particular. For the most time some of the standard manhole covers are installed in a street. Taking a look at manholes in Minneapolis city, they inform visitors what the landmark, landscape, symbol, representative flower or tree of the city is. Sometimes they are designed by famous artists and become art which all pedestrian can enjoy. If manhole covers in 'the streets of history and culture' are designed to represent its history or culture, visitors will get information about there easily and enjoy their design. To foster manhole cover designs, the government office should co-work with professional designers or design societies and encourage people to spend a certain amount of the construction cost to design manhole covers. At school designing manhole cover can be handled in an art class and besides can have a class in the field, streets to observe manhole cover designs. Getting more concern of manhole cover design, competitions and exhibitions are able to be held.

• Bulletin of the Korean Mathematical Society
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• v.54 no.3
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• pp.875-894
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• 2017

Let $[n]=\{1,2,{\ldots},n\}$. A set ${\mathbf{A}}=\{A_1,A_2,{\ldots},A_l\}$ is a minimal cover of [n] if ${\cup}_{1{\leq}i{\leq}l}A_i=[n]$ and $$\bigcup_{{1{\leq}i{\leq}l,}\\{i{\neq}j_0}}A_i{\neq}[n]\text{ for all }j_0{\in}[l]$$. Let ${\mathcal{C}}(n)$ denote the collection of all minimal covers of [n], and write $C_n={\mid}{\mathcal{C}}(n){\mid}$. Let ${\mathbf{A}}{\in}{\mathcal{C}}(n)$. An element $u{\in}[n]$ is critical in ${\mathbf{A}}$ if it appears exactly once in ${\mathbf{A}}$. Two minimal covers ${\mathbf{A}},{\mathbf{B}}{\in}{\mathcal{C}}(n)$ are said to be restricted t-intersecting if they share at least t sets each containing an element which is critical in both ${\mathbf{A}}$ and ${\mathbf{B}}$. A family ${\mathcal{A}}{\subseteq}{\mathcal{C}}(n)$ is said to be restricted t-intersecting if every pair of distinct elements in ${\mathcal{A}}$ are restricted t-intersecting. In this paper, we prove that there exists a constant $n_0=n_0(t)$ depending on t, such that for all $n{\geq}n_0$, if ${\mathcal{A}}{\subseteq}{\mathcal{C}}(n)$ is restricted t-intersecting, then ${\mid}{\mathcal{A}}{\mid}{\leq}{\mathcal{C}}_{n-t}$. Moreover, the bound is attained if and only if ${\mathcal{A}}$ is isomorphic to the family ${\mathcal{D}}_0(t)$ consisting of all minimal covers which contain the singleton parts $\{1\},{\ldots},\{t\}$. A similar result also holds for restricted r-cross intersecting families of minimal covers.

• Journal of the Korea Convergence Society
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• v.12 no.11
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• pp.275-284
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• 2021

This study analyzes the characteristics regarding the image of women in feminist magazine covers. Along with fundamental analysis of the female image that appeared on the covers of feminist magazines and the grammar of visual design by Kress and van Leeuwen, a methodology of socio semiotic research, this study explores the structure and driving principles of symbols that have organized female images. The subject of analysis is set to 200 covers of magazines published from the 1960s to the 2010s. Through analysis, first, female images represented in the covers of feminist magazines showed women of various races, age groups, appearances, and occupations, and the degree od emphasis on the physique was fewer and natural-looking. Second, the study confirms that feminist magazines actively utilize representational and interactive metafunctions to deliver symbolic information such as messages of confidence, strength, and courage. Third, the organized symbols affected the recipient's understanding and interpretation of images. I hope this study helps to contemplate ways to express female images and the dynamic and diverse aspects of women.