• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.120-120
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• 2006

In our study grazing incidence X-ray scattering (GIXS) measurements with synchrotron radiation sources were conducted statically and in-situ for a series of nanoscale thin films prepared from nanoporous dielectrics, block copolymers, brush polymers, and molecular assemblies. All GIXS measurements were performed at the Pohang Accelerator Laboratory. The measured scattering data were analyzed in detail by using newly developed GIXS scattering theory. All GIXS results will be discussed in details with considering the materials chemistry and nanostructure formation process parameters.

• Journal of Powder Materials
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• v.20 no.5
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• pp.332-337
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• 2013

Recently, self-propagating high-temperature synthesis (SHS), related to metallic and ceramic powder interactions, has attracted huge interest from more and more researchers, because it can provide an attractive, energy-efficient approach to the synthesis of simple and complex materials. The adiabatic temperature $T_{ad}$ and apparent activation energy analysis of different thermit systems plays an important role in thermodynamic studies on combustion synthesis. After establishing and verifying a mathematic calculation program for predicting adiabatic temperatures, based on the thermodynamic theory of combustion synthesis systems, the adiabatic temperatures of the NiO/Al aluminothermic system during self-propagating high-temperature synthesis were investigated. The effect of a diluting agent additive fraction on combustion velocity was studied. According to the simulation and experimental results, the apparent activation energy was estimated using the Arrhenius diagram of $ln(v/T_{ad}){\sim}/T_{ad}$ based on the combustion equation given by Merzhanov et al. When the temperature exceeds the boiling point of aluminum (2,790 K), the apparent activation energy of the NiO/Al aluminothermic system is $64{\pm}14$ kJ/mol. In contrast, below 2,790 K, the apparent activation energy is $189{\pm}15$ kJ/mol. The process of combustion contributed to the mass-transference of aluminum reactant of the burning compacts. The reliability of the simulation results was experimentally verified.

• Cartoon and Animation Studies
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• s.49
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• pp.203-220
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• 2017

In the field of visual arts, the introduction of synthesis allowed us to express various expressions that were outside the constraints of time and space. Digital synthesis is constrained by realistic representation due to technical limitations. However, it is no exaggeration to say that after digital synthesis has been fully established, at least the limits of image representation through synthesis have almost disappeared. The existing research papers on composing are either technical studies on the production techniques, or the synthesis was mainly focused on the change of the space-time concept and meaning of the visual arts. I felt the need for research on. In addition, I felt the need to look back on the changes in my view of art. Therefore, in this paper, rather than dealing with the conceptual theory of the technical part or spatio-temporal extension, it is necessary to classify it as natural, heterogeneous, heterogeneous and natural according to the traits revealed in the artistic expression of art, And diversity.

• Composites Research
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• v.19 no.2
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• pp.28-34
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• 2006

[ $Cu-TiB_2$ ] metal matrix composites with various weight fractions of $TiB_2$ were fabricated by combination of manufacturing process, SPS (self-propagating high-temperature synthesis) and SPS (spark plasma sintering). The feasibility of $Cu-TiB_2$ composites for welding electrodes and sliding contact material was investigated through experiments on the tensile properties, hardness and wear resistance. To obtain desired properties of composites, composites are designed according to reinforcement's shape, size and volume fraction. Thus proper modeling is essential to predict the effective material properties. The elastic moduli of composites obtained by FEM and tensile test were compared with effective properties from the original Eshelby model, Eshelby model with Mori-Tanaka theory and rule-of-mixture. FEM result showed almost the same value as the experimental modulus and it was found that Eshelby model with Mori-Tanaka theory predicted effective modulus the best among the models.

• Advances in nano research
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• v.9 no.3
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• pp.193-210
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• 2020

In this research, beside presenting real images of produced Functionally Graded Carbon Nanotube-Reinforced Composites (FG-CNTRCs) and a brief review of the synthesis method of FG-CNTRCs, static and buckling analysis of FG-CNTRC with piezoelectric layers are investigated. It is assumed that the material properties of FG-CNTRC are varied through the thickness direction using four different distributions of Carbon Nanotubes (CNTs). To capture the size effects, nonlocal elasticity theory proposed by A.C. Eringen is also adopted in our model. One of the topics in our paper is using a higher order theory with eight different displacement fields and comparing their results with each other. To solve the governing equations, an analytical method is used to find the deflections and critical buckling loads of FG-CNTRCs. To show the accuracy of present methodology, our results are compared with the results of simply supported rectangular nano plates available in the literature. In this research, the effects of aspect ratio, piezoelectric layer and nonlocal parameter are also studied. It is hoped that this work leads to more accurate models on FG-CNTRC.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.433-437
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• 2003

Quantitative Feedback Theory (QFT) is one of effective methods of robust controller design. In QFT design we can considers the phase information of the perturbed plant so it is less conservative than $H_{\infty}$ and ${\mu}$-synthesis methods and as be shown, it is more transparent than the sensitivity reduction methods mentioned . In this paper we want to overcome the major drawback of QFT method which is lack of an automatic method for loop-shaping step of the method so we focus on the following problem: Given a nominal plant and QFT bounds, synthesize a controller that achieves closed-loop stability and satisfies the QFT boundaries. The usual approach to this problem involves loop-shaping in the frequency domain by manipulating the poles and zeros of the nominal loop transfer function. This process now aided by recently developed computer aided design tools proceeds by trial and error and its success often depends heavily on the experience of the loop-shaper. Thus for the novice and First time QFT user, there is a genuine need for an automatic loop-shaping tool to generate a first-cut solution. Clearly such an automatic process must involve some sort of optimization, and while recent results on convex optimization have found fruitful applications in other areas of control theory we have tried to use LMI theory for automating the loop-shaping step of QFT design.

• Speech Sciences
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• v.3
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• pp.83-92
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• 1998

Vowels are classified by vocal tract shapes. These shapes form constriction points along the tract, which have an influence on such vocal tract resonance as $F_l,\;F_2,\;F_3$, and so on. This study reviews the perturbation theory of the tract and determines the corresponding formant frequencies from modified vocal tracts using vocal tract area function. Then, formant variation is observed from the theory. Finally, each set of $F_l,\;F_2,\;and\;F_3$ frequency is input to a speech synthesis software to make a vowel sound. Auditory impression of each sound without any modification of its vocal tract shape is almost the same as the corresponding phonetic symbol. Formant frequencies of $F_l,\;F_2,\;F_3$ vary according to the perturbation theory. Generally, constriction along the node causes formant values to decrease while constriction along the anti-node cause it to increase. Vocal tracts modified by more than $3\;cm^2$ change vowel qualities of /a/ and /i/ into those of f /v/ and /$\varepsilon$/, respectively. This study will be helpful in simulating sounds from modified vocal tracts before any operation. Further studies are desirable to compare vocal tract shapes of various languages and their sounds together.

• International Journal of Contents
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• v.12 no.2
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• pp.49-57
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• 2016

This paper aims to explore instructional design of a cyber classroom for secondary students' basic English language competence. A paucity of support for low or under achieving students' English learning exists particularly at the secondary level. In order to bridge the gap, there has been demand for online educational resources considered to be an effective tool in improving students' self-directed learning and motivation. This study employs a comprehensive approach to instructional design for the asynchronous cyber classroom with the underlying premise that different learning theories can be applied in a complementary manner to serve different pedagogical purposes best. Gagné's conditions of learning theory, Bruner's constructivist theory, Carroll's minimalist theory, and Vygotsky's social cognitive development theory serve as the basis for designing instruction and selecting appropriate media. The ADDIE model is used to develop online teaching and learning materials. Twenty-five key grammatical features were selected through the analysis of the national curriculum of English, being grouped into five units. Each feature is covered in one cyber asynchronous class. An Integration Class is given at the end of every five classes for synthesis, where students can practice grammatical features in a communicative context. Related theories, pedagogical practices, and practical web-design strategies for cyber Basic English classes are discussed with suggestions for research, practice and policy to support self-directed learning through a cyber class.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.44 no.1
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• pp.57-69
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• 2016

There are three kinds of algorithms(2-ARE, mu-synthesis, LMI) for controller design using closed-loop shaping method. This paper provides the summary of background theory of three algorithms and $H_{\infty}$ controller design results for spacecraft attitude control using the three controller design tools of Matlab$^{TM}$ Toolbox for comparison. As a result, it reveals that LMI design method is more reliable as well as easier than others for spacecraft attitude control design. Comparison results are as follow: 2-ARE method and LMI method provide almost same results in robust stability, robust performance and control authority level. But 2-ARE method is more sensitive than LMI method with respect to proper design of weighting functions: 2-ARE method is more difficult than LMI method in weighting function design. The design result of mu-synthesis method shows worse performance and requires bigger control authority than others.

• Korean Institute of Interior Design Journal
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• v.21 no.4
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• pp.57-67
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• 2012

The goal of this research is to study the spatial and temporal disjunctive composition of the movie 'Kill Bill part 1/2' and to lay a foundation for the future exploration of the topological relationship between contemporary architecture and cinema based upon the spatial and temporal multiplicity. Since the birth of cinema in early 20 century, architecture and cinema have a dynamic interdisciplinary relationship as Soviet director and theorist Sergei Eisenstein has called the Acropolis of Athens as 'one of the most ancient films' based upon its cinematic spatial sequence, and contemporary architect and theorist Bernard Tschumi has adopted cinematic montage technique to create his own disjunctive event-structure. As french philosopher Gilles Deleuze has traced the cinematic version of his 'disjunctive synthesis' from Eisentein's 'dialectic montage', Deleuzian 'disjunctive synthesis' can be discovered not only from the work and theory of Bernard Tschumi and Rem Koolhaas, but also from the 'Kill Bill's disjunctive composition where the heterogeneous spatial images and temporal images are under continuous interaction to create rhizomatic relationship between the cinema and viewers.