• Korea-Australia Rheology Journal
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• v.16 no.4
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• pp.183-191
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• 2004

High Deborah or Weissenberg number problems in viscoelastic flow modeling have been known formidably difficult even in the inertialess limit. There exists almost no result that shows satisfactory accuracy and proper mesh convergence at the same time. However recently, quite a breakthrough seems to have been made in this field of computational rheology. So called matrix-logarithm (here we name it tensor-logarithm) formulation of the viscoelastic constitutive equations originally written in terms of the conformation tensor has been suggested by Fattal and Kupferman (2004) and its finite element implementation has been first presented by Hulsen (2004). Both the works have reported almost unbounded convergence limit in solving two benchmark problems. This new formulation incorporates proper polynomial interpolations of the log­arithm for the variables that exhibit steep exponential dependence near stagnation points, and it also strictly preserves the positive definiteness of the conformation tensor. In this study, we present an alternative pro­cedure for deriving the tensor-logarithmic representation of the differential constitutive equations and pro­vide a numerical example with the Leonov model in 4:1 planar contraction flows. Dramatic improvement of the computational algorithm with stable convergence has been demonstrated and it seems that there exists appropriate mesh convergence even though this conclusion requires further study. It is thought that this new formalism will work only for a few differential constitutive equations proven globally stable. Thus the math­ematical stability criteria perhaps play an important role on the choice and development of the suitable con­stitutive equations. In this respect, the Leonov viscoelastic model is quite feasible and becomes more essential since it has been proven globally stable and it offers the simplest form in the tensor-logarithmic formulation.

• Bulletin of the Korean Chemical Society
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• v.32 no.7
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• pp.2358-2368
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• 2011

Density functional theory (DFT) and time-dependent density functional theory (TDDFT) calculations, employing the B3LYP method and the LANL2DZ, 6-31G$^*$(LANL2DZ for Tc), 6-31G$^*$(cc-pVDZ-pp for Tc) and DGDZVP basis sets, have been performed to investigate the electronic structures and absorption spectra of the technetium-99m-labeled methylenediphosphonate ($^{99m}Tc$-MDP) complex of the simplest diphosphonate ligand. The bonding situations and natural bond orbital compositions were studied by the Mulliken population analysis (MPA) and natural bond orbital (NBO) analysis. The results indicate that the ${\sigma}$ and ${\pi}$ contributions to the Tc-O bonds are strongly polarized towards the oxygen atoms and the ionic contribution to the Tc-O bonding is larger than the covalent contribution. The electronic transitions investigated by TDDFT calculations and molecular orbital analyses show that the origin of all absorption bands is ascribed to the ligand-to-metal charge transfer (LMCT) character. The solvent effect on the electronic structures and absorption spectra has also been studied by performing DFT and TDDFT calculations at the B3LYP/6-31G$^*$(cc-pVDZ-pp for Tc) level with the integral equation formalism polarized continuum model (IEFPCM) in different media. It is found that the absorption spectra display blue shift in different extents with the increase of solvent polarity.

• Journal of Korean Society of Transportation
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• v.28 no.4
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• pp.19-30
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• 2010

It has become important to have some proper guidelines of how to provide public transport information services in response to the rapid IT developments and the wide spread of public information services. The current study takes a contextual approach to the analysis of public transportation information use under a dynamic decision situation, complementing the conventional cross-sectional approaches. Using the CHAID of decision tree induction based on decision table formalism applied to the survey data of activity travel and information use, the study found that the information type and medium choices are strongly affected by the decision contexts in addition to the individuals' socio-demographic characteristics. The results suggest an important implication to the market segmentation of information services for public transportation.

• Journal of Korea Multimedia Society
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• v.6 no.6
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• pp.1088-1099
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• 2003

The syntax-directed translation using semantic actions is frequently used in construction of compiler for text programming languages. it is very useful for the language designers to develop compiler back-end using a syntax structure of a source programming language. Due to the lack of the integrated representation method for a parse tree node and modeling method of syntax structures, it is very hard to construct compiler using syntax-directed translation in visual languages. In this Paper, we propose a visual language compiler generation method for constructing a visual languages compiler automatically, using syntax-directed translation. Our method uses the Picture Layout Grammar as a underlying grammar formalism. This grammar allows our approach to generate parser efficiently u sing And-Or-Waiting Graph and encapsulating syntax definition as one unit. Unlike other systems, we suggest separating the specification and the generation of semantic actions. Because of this, it provides a very efficient method for modification.

• Journal of the Korean Society of Costume
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• v.50 no.3
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• pp.13-30
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• 2000

The purpose of this study was to analyzed the types of Deformation dipicted on the late 1990s western costumes. The late 20th century cultural experience or lifestyle is interpreted with 'popular culture' ,popular culture is described as cultural phenomenon in postmodern condition. Contemporary popular culture may no longer be strictly 'working-class' as the idealistic purists of political formalism would like to , but does emerge from subordinate cultures, from the inventive edges of the consensus, and from the previously ignored and suppressed. It gestured through a widening democratization of styles, sounds and images, to an important remarking , to new possibilities , new perpectives, new projects. The growing importance of popular culture as a source for change of expression in the art, expecially new desire and will of artists has been caused lots of ' Deformation' in their works. Deformation, doesn't mean to represent object faithfully as it were seen through the artist's eyes. In a sense it implies that artists deform it with conscious or unconscious form. So in this study , the phenomenon of the postmodern western costumes is to describe ' formative language' called 'Deformation.' and it is classified three types, that is, 'Deformation of human-body image.' , Deformation of silhouette.' 'Deformation of detail.'. First , Deformation of human-body image is represented by deconstructive , subversive image in western costumes, a lot of costumes types of deconstruction have been shown by fashion designers are emphasized empathy with Deformation of human-body image. Second, Deformation of silhouette is also represented subversion of traditional manner and ultiity, underwear and outwear structure and ugly image. parody image of postumodernism , and so on. Above all, the late 1990s western costumes with Deformation of silhouette was an infinitely larger and more complex world than it appeared from outside and has expressed as a rejection against the values which traditional aesthetic concept had pursued, And parody through the change of internal meaning is to bring about parodox, irony, contempt, satire , unexpectedness by applying the original to inapproporate subject through its substition, inversion. Third, Deformation of detail is represented overdecoration, exaggerative distortion of for , overlapping and fetish image, parody image, kitsch image, and so on , Once fetish achieve a certain' style factor' among trendsettler, they are picked up by internationally famous fashion designers, The characteristics of kitsch are overdecoration , unfitness , imitation , used western costumes.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.425.1-425.1
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• 2014

Thermal transport in nanomaterials is not only scientifically interesting but also technological important for various future electronic, bio, and energy device applications. Among the various computation approaches to investigate lattice thermal transport phenomena in nanoscale, the atomistic nonequilibrium Green's function approach based on first-principles density functional theory calculations appeared as a promising method given the continued miniaturization of devices and the difficulty of developing classical force constants for novel nanoscale interfaces. Among the nanometerials, carbon atomic chains, namely the cumulene (all-doulble bonds, ${\cdots}C=C=C=C{\cdots}$) and polyyne (alternation of single and triple bonds, ${\cdots}C{\equiv}C-C{\equiv}C{\cdots}$) can be considered as the extream cases of interconnction materials for nanodevices. After the discovery and realization of carbon atomic chains, their electronic transport properties have been widely studied. For the thermal transport properties, however, there have been few literatures for this simple linear chain system. In this work, we first report on the development of a non-equilibrium Green's function theory-based computational tool for atomistic thermal transport calculations of nanojunctions. Using the developed tool, we investigated phonon dispersion and transmission properties of polyethylene (${\cdots}CH2-CH2-CH2-CH2{\cdots}$) and polyene (${\cdots}CH-CH-CH-CH{\cdots}$) structures as well as the cumulene and polyyne. The resulting phonon dispersion from polyethylene and polyene showed agreement with previous results. Compared to the cumulene, the gap was found near the ${\Gamma}$ point of the phonon dispersion of polyyne as the prediction of Peierls distortion, and this feature was reflected in the phonon transmission of polyyne. We also investigated the range of interatomic force interactions with increase in the size of the simulation system to check the convergence criteria. Compared to polyethylene and polyene, polyyne and cumulene showed spatially long-ranged force interactions. This is reflected on the differences in phonon transport caused by the delicate differences in electronic structure.

• Journal of KIISE:Software and Applications
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• v.35 no.1
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• pp.12-21
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• 2008

As the usage of computer systems is increasing in our lives, the reliability and safely of these systems need to be thoroughly checked through the verification techniques. As a basic formalism for several modeling methods, the finite state machine (FSM) is widely used in specification and verification of system models. And there is a technique for ing internal events of FSM in order to effectively analyze the system. However, this technique does not handle the state explosion problem since it can be applied after completely generating all the state space of the system. In this research, we provide a new approach for efficiently representing concurrent properties of FSM, the slice model and provide an efficient transition reduction method based on the slice model. Our approach is effective in time and space perspective since it is peformed by partially generating the needed system states while the existing abstraction technique can be applied to all the system states.

• Korean Journal of Logic
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• v.17 no.1
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• pp.33-70
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• 2014

We still do not know against what histocial/philosophical background and motivation was Tarski's definition of logical consequence introduced, even if it has had such a strong influence. In view of the centrality of the notion of logical consequence in logic and philosophy of logic, it is rather shocking. There must be various intertwined reasons to blame for this uncomfortable situation. There has been remarkable progress achieved recently on the history of analytic philosophy and modern logic. In view of the recent developments of the controversies involved, however, we will have to wait years to resolve all this uneasiness. In this gloomy situation, Douglas Patterson's recent study of Tarski's philosophy of language and logic seems to have the potential to turn out to be a ground breaking achievement. [Patterson (2012)] This article aims at reporting the state-of-the-art in this problem area, and fathoming the future directions of research by examining critically some unclear components of Patterson's study.

• The Journal of the Korea Contents Association
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• v.13 no.10
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• pp.151-159
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• 2013

Formalism narrative theory adopts the dualism of Fabula, story material and Sujet, story substance. The recent theories of storytelling convert the dualism into story and storytelling. This essay delves into the mechanism of contemporary storytelling by comparatively analyzing the storytelling of two films, A Korean film, Family Ties and A Hollywood film, Little Miss Sunshine, which are considered to represent contemporary storytelling. While the latter builds its structure through desire usually shown in the classical Hollywood films, the former has the structure which has nothing to do with causality by displaying fragmented stories. And the latter has typical characters, while the former shows totally different reality, using the obscure characters. In conclusion, Little Miss Sunshine has a storytelling which puts audience feeling in tune by controlling it, and Family Ties has one which delivers director's intention.

• Nuclear Engineering and Technology
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• v.23 no.4
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• pp.426-437
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• 1991

The $He^{++}$ beam transport system of the SNU 1.5-MV Tandem Van de Graaff accelerator is analysed by ion optical approach. The program OPTRANS is developed to determine the optimum operating conditions of each ion optical component and to simulate ion beam transport. First order matrix formalism is used and the space charge effect is neglected. Optimum operating conditions for the transport of 0.5~3.0 MeV $He^{++}$ beam are determined by the use of the program OPTRANS. Initial ion beam omittance is assumed to be 0.5$\times$80.0 mm.mrad from the structure of the extraction electrode and the experiment of ion beam extraction. ion beam transport characteristics of each ion optical component according to the variation of the operating conditions are investigated, and operating conditions to minimize the beam size at each slit, stripping foil, and target are calculated. Optimum operating conditions obtained from the experiment of ion beam transport show a discrepancy of less than 15% compared with the calculated ones. From the simulation and experiment of ion beam trans-port, the validity of the calculated optimum operating conditions and the usefulness of the program OPTRANS are verified.