• Journal of the Korean Ceramic Society
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• v.46 no.5
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• pp.493-496
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• 2009

Phase stabilized leucite, which has high coefficient of thermal expansion, was synthesized, and its thermal expansion behavior was investigated. The homogeneous leucite phase was synthesized by solid state reaction from the mixture of $K_2CO_3-Al_2O_3-SiO_2$. and its stabilization from tetragonal to cubic phase was attempted by adding $Cs_2CO_3$ into starting materials. And fine powder with an average particle size of a few hundreds ${\mu}m$ were fabricated by planetary milling. During milling, amorphization of leucite was observed and recrystallized after heat treatment. The thermal expansion behavior of tetragonal and cubic leucite has measured and discussed. The average coefficient of thermal expansion of tetragonal and cubic phase leucite from room temperature to $750^{\circ}C$ was $21.4{\times}10^{-6}/^{\circ}C$ and $14.5{\times}10^{-6}/^{\circ}C$, respectively.

• Asian Journal of Innovation and Policy
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• v.12 no.1
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• pp.054-074
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• 2023

With the advent of the '4th Industrial Revolution', digitalization using AI (Artificial Intelligence), big data, IoT (Internet of Things), cloud computing and mobile is accelerating across all industries and global companies have fundamentally reorganized customer experiences, business models, and operations centering on digital transformation. Business innovation drives productivity improvement, process simplification, price, competitiveness and sustainable expansion. Whether digital transformation will be necessary for the current industrial environment is no longer important, and how quickly companies achieve digitalization has emerged as the utmost crucial element in industrial continuity. As non-face-to-face and remote technologies have begun in earnest, and accelerated in the pharmaceutical industry. They are looking for ways to provide value, generate profits, improve efficiency, and sustain the future. Compared to other industries, the pharmaceutical-related sectors have shown high interest in digital transformation especially to reduce costs and meet the challenge of delivering products during the pandemic environment.

• Proceedings of the KWS Conference
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• 1999.10a
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• pp.310-313
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• 1999

This paper represents to develop a computer software system which is capable to analyze the phase transformation of high strength steel(BV-AH32) and to predict heat transfer, residual stress due to phase transformation during Gas Metal Arc(GMA) welding. The developed model was taken into account temperature dependent of young's modules, coefficient of thermal expansion and yield stress as well as the double ellipsoidal heat distribution by the moving arc. The results showed that the longitudinal and transverse residual stresses calculated by the coupled analysis of heat transfer, residual stress and phase transformation are in good agreement with the experimental data. In addition, the temperature distribution as well as longitudinal and transverse residual stresses of weldment were determined at the 1-pass and 2-pass of welding.

• Journal of the Korean Ceramic Society
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• v.28 no.7
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• pp.549-555
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• 1991

Mullite-zirconia (0∼4 mol% yttria) composites were obtained by In-situ sintering of zircon and alumina mixture, and their mechanical properties were studied in conjuction with microstructure observation. Martensitic transformation temperature (Ms) of zirconia dispersed in the mullite matrix decreased with Y2O3 contents and was about 600$^{\circ}C$ for ZrO2 containing 4 mol% Y2O3. On cooling of this composites, tetragonal to monoclinic phase transformation induced microcracks at the grain boundary of mullite matrix. The microcracks seemed to absorb the fracture energy in stress field during mechanical tests. Therefore, toughening mechanisms of this composite were considered to nucleation and extension of microcrack, and crack deflection mechanism due to the difference of thermal expansion coefficient between matrix and dispersed phase.

• Proceedings of the KWS Conference
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• 2005.11a
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• pp.26-28
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• 2005

The purpose of this study is to evaluate the behavior of the welding distortion of the 9% Ni steel weldment involving the martensitic phase transformation. In order to do it, an uncoupled thermal-mechanical finite element (FE) model was developed to evaluate the effect of the phase transformation on the distortion for the weldment. High speed quenching dilatometer tests were employed to define the variations of the coefficient of thermal expansion (CTE) with the fraction of the martensitic phase transformation, which strongly depends on the cooling speed after welding. Comprehensive experiments for the welding distortion of the weldment with reference to welding heat input were employed to verify the FE model.

• Journal of the Korean Mathematical Society
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• v.49 no.4
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• pp.867-879
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• 2012

For ${\beta}$ > 1, let $T_{\beta}$ : [0, 1] ${\rightarrow}$ [0, 1) be the ${\beta}$-transformation. We consider an invariant $T_{\beta}$-orbit closure contained in a closed interval with diameter 1/${\beta}$, then define a function ${\Xi}({\alpha},{\beta})$ by the supremum such $T_{\beta}$-orbit with frequency ${\alpha}$ in base ${\beta}$, i.e., the maximum value in $T_{\beta}$-orbit closure. This paper effectively determines the maximal domain of ${\Xi}$, and explicitly specifies all possible minimal intervals containing $T_{\beta}$-orbits.

• Korean Journal of Computational Design and Engineering
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• v.5 no.3
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• pp.276-284
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• 2000

Usual practice of the transformation of a B-spline curve into a set of piecewise polynomial curves in a power form is done by either a knot refinement followed by basis conversions or applying a Taylor expansion on the B-spline curve for each knot span. Presented in this paper is a new algorithm, called a direct expansion algorithm, for the problem. The algorithm first locates the coefficients of all the linear terms that make up the basis functions in a knot span, and then the algorithm directly obtains the power form representation of basis functions by expanding the summation of products of appropriate linear terms. Then, a polynomial segment of a knot span can be easily obtained by the summation of products of the basis functions within the knot span with corresponding control points. Repeating this operation for each knot span, all of the polynomials of the B-spline curve can be transformed into a power form. The algorithm has been applied to both static and dynamic curves. It turns out that the proposed algorithm outperforms the existing algorithms for the conversion for both types of curves. Especially, the proposed algorithm shows significantly fast performance for the dynamic curves.

• Fashion & Textile Research Journal
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• v.13 no.1
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• pp.7-16
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• 2011

Maximalism is the code which has a power to interpret a fashion phenomenon expressed complexly and variously in the multicultural society. In the 21st century, maximalism which reappeared is not the expression by a method only. It is presenting the experimental design for the new pursuit through the mixture such as expansion, splendor, variety, decoration, distortion of configuration or transformation, and composition. Therefore, this study aims at analyzing expression of fashion design by four types(expansion, decoration, mixture, non-structure) materializing a feature of maximalism expressed in the domestic and foreign collection works from 2005 to 2010. The research results are as follows. 1. Expansion: It was showed artificial, formative, unique, and odd teatures through the expansion of the upper half of the body, the lower half of the body, and both of them. 2. Decoration: It was showed the actual decoration considering functionality and practicality and the decoration emphasizing and unique character and featuring domination and emphasis. 3. Mixture: It was showed through the mixture of the contrary textiles or the different sex image. 4. Non-structure: It showed the non-structure of the avant-garde trend and non-structure through decoration, detail, adjustment direction of a dress.

• Journal of Semiconductor Engineering
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• v.2 no.3
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• pp.136-141
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• 2021

This paper analyzes the tree expansion for multiple-input multiple-output (MIMO) detection in the viewpoint of hardware implementation. The tree expansion is to calculate path metrics of child nodes performed in every visit to a node while traversing the detection tree. Accordingly, the tree-expansion unit (TEU), which is responsible for such a task, has been an essential component in a MIMO detector. Despite the paramount importance, the analyses on the TEUs in the literature are not thorough enough. Accordingly, we further investigate the hardware complexity of the TEUs to suggest a guideline for selection. In this paper, we focus on a pair of major ways to implement the TEU: 1) a full parallel realization; 2) a transformation of the formulae followed by common subexpression elimination (CSE). For a logical comparison, the numbers of multipliers and adders are first enumerated. To evaluate them in a more practical manner, the TEUs are implemented in a 65-nm CMOS process, and their propagation delays, gate counts, and power consumptions were measured explicitly. Considering the target specification of a MIMO system and the implementation results comprehensively, one can choose which architecture to adopt in realizing a detector.

• Architectural research
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• v.25 no.2
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• pp.29-40
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• 2023

The purpose of this study is to analyze the conflicts caused by the spatial expansion in two types of urban heritage in Seoul. To explain the national and professional orientation found in each spatial transformation, the study brought the concept of 'historic state' and 'epitome,' thereby examining the operating system of the conflicts. Field observations and stakeholder interviews were performed based on literature and historical research. The study results are as follows. ①In the case of Gwanghwamun and Donuimun, the spatial expansion is to find the historic state of the sites. Gwanghwamun with high national status and substance, conflicts show a pattern that spreads to memory conflicts. Donuimun is relatively unknown and has no substance so that a flexible method of digital restoration was applied. ② In the case of Ikseon-dong and Bukchon hanok, they show heterogeneous spatial expansion. The conflicts in relation to this is caused by the epitome of hanok. In Ikseon-dong, illegal installation of structures(non-epitome) is prevalent, while in Bukchon, there was a process of transferring the new basement(non-epitome) as part of the hanok. ③Conflicts in Gwanghwamun can be coordinated by referring to the digital restoration of Donuimun, and conflicts in Ikseon-dong can be resolved by taking Bukchon as a precedent.