• Proceedings of the Korean Society of Precision Engineering Conference
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• 1997.10a
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• pp.572-575
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• 1997

The embedded atom method based on density functional theory was developed as a new means for calculating ground state properties of realistic metal system by Murray S. Daw, Stephen M. Foiles and Michael I. Baskes. In the paper, we had corrected constitutive formulae and parameters on the nickel for the purpose of doing Embedded Atom Method analysis. And then we have computed the properties of the nickel on the fundamental scale of the atomic structure. In result, simulated ground state properties, such as the lattice constant, elastics constants and sublimation energy, show good agreement with Daw's simulation data and with experimental data.

• Journal of the Korean Applied Science and Technology
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• v.26 no.3
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• pp.306-316
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• 2009

In this study, block copolymer of polystyrene and polyethylene glycol methyl ether methacrylate(PEGMA) by ATRP(atom transfer radical polymerization) method was synthesized. 4 arm-molecule which contained halogen atom was synthesized for an initiator. With 4 arm-molecule monodispered polystyrene were synthesized by ATRP method. The molecular change of synthesized monodispersed polystyrene with respect to time was investigated and living polymer characteristic was confirmed. Block copolymer of polystyrene and polyethylene glycol methyl ether methacrylate(PEGMA) was synthesized by ATRP with macroinitiator which was synthesized from the monodispersed polystyrene(Mn=12000). The molecular weight of obtained PS-b-PEGMA was 22,000.

• Applied Microscopy
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• v.46 no.3
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• pp.127-133
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• 2016

Atom probe tomography is a time-of-flight mass spectrometry-based microanalysis technique based on the field evaporation of surface atoms of a tip-shaped specimen under an extremely high surface electric field. It enables three-dimensional characterization for deeper understanding of chemical nature in conductive materials at nanometer/atomic level, because of its high depth and spatial resolutions and ppm-level sensitivity. Indeed, the technique has been widely used to investigate the elemental partitioning in the complex microstructures, the segregation of solute atoms to the boundaries, interfaces, and dislocations as well as following of the evolution of precipitation staring from the early stage of cluster formation to the final stage of the equilibrium precipitates. The current review article aims at giving a comment to first atom probe users regarding the limitation of the techniques, providing a brief perspective on how we correctly interprets atom probe data for targeted applications.

• Proceedings of the Optical Society of Korea Conference
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• 2004.02a
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• pp.50-51
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• 2004

• Proceedings of the Optical Society of Korea Conference
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• 2004.02a
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• pp.52-53
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• 2004

• Proceedings of the Optical Society of Korea Conference
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• 2001.02a
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• pp.250-251
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• 2001

There is a considerable interest in the generation of a cold atomic beam having a narrow velocity spread that can be used in various experiments in physics such as ultrahigh resolution atomic and molecular spectroscopy, atom optics, atom interferometry, study of solid surfaces, and low energy collision experiments. The invention of the techniques of laser cooling has stimulated developments in the production of cold and bright atomic beams. (omitted)

• Bulletin of the Korean Chemical Society
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• v.10 no.2
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• pp.161-167
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• 1989

The results of ab initio(MP2/6-31G) molecular orbital calculations of the dipole moment derivatives and gas phase IR intensities in chloromethanes are reported. The theoretical polar tensors are analyzed into the net charge, charge-flux, and overlap contributions. The charge-flux contribution was found to be dominant in the Cl atom polar tensor, while the net charge effect was the most prominent contribution for the H atom polar tensor. The Cl atom polar tensor appeared, in a good approximation, to be transferable among various chloro molecules. On the other hand, for the prediction of IR spectra of complex hydrocarbons containing chlorine atoms, some empirical adjustment of the H-atom polar tensor seemed to be made depending on the number of Cl atoms bound to the certain carbon atom.

• Bulletin of the Korean Chemical Society
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• v.33 no.6
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• pp.1867-1872
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• 2012

The 5-parameter Morse potential (5-MP) method for the interaction between O atom and Cr surfaces is constructed in the present work. The adsorption of O on Cr (100), (110), (111), and (211) surfaces are studied with 5-MP in detail. The fourfold hollow site of the Cr (100) surface is favored for O atom. On Cr (110), quasithreefold site is favored with the parallel frequencies (the frequencies of O atom paralleling the metal surface) of 342 and 538 $cm^{-1}$, and perpendicular frequency (the frequency of O atom perpendicular to the metal surface) at 526 $cm^{-1}$. On Cr (111), the most favored mode for O atom is found to be the quasi-threefold site with the perpendicular frequency at 553 $cm^{-1}$ and the parallel frequencies at 253 and 399 $cm^{-1}$. According to our calculation results, we speculate the most preferred mode for O adsorption on Cr (211) surface is the quasithreefold site with the perpendicular frequency at 583 $cm^{-1}$ and the parallel frequencies at 449 and 185 $cm^{-1}$.

• International Journal of Advanced Culture Technology
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• v.8 no.4
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• pp.294-298
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• 2020

We was constructed of the spread movement with tremor layer point by the tractile-dot structure that was analyzed the squirm quake forms of the perception movement on the atom liquid. Algorithm of squirm quake forms was used to move the spread tremor on the atom state. To detect the tiny signal, we compared the association average value of the squirm quake form on the atom state. Their subject were issued the valuation standard and perception movement for basic atom condition by the spread tremor. We take to detect the tiny scores of average during perception movement side from the spread tremor that magnetic condition get to a variation of the Ma-αAVG and Ma-αMAX-MIN with 6.25±0.35 units, that electric condition get to a variation for the El-αAVG and El-αMAX-MIN with 5.68±0.42 units. The spread tremor was to investigate the capacity of the tremor form, to uptake a spread data of spread tremor level on the CCPL that was denoted the calm-classification form by the spread perception level system. As the squirm quake forms was demanded by the spread tremor signal, max-average values of perception movement were checked the spread position for association average data. We make mention of squirm quake forms for a signal association and a quake data signal of relation system.

• Journal of the Korean Chemical Society
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• v.51 no.5
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• pp.423-432
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• 2007

In this study we investigated the types of inscriptions representing the concept of atom and molecule in the 9th grade science textbooks developed under the 7th National Curriculum, and analyzed the processes of interpreting those inscriptions on the view of semiotics. The concept of atom and molecule was represented in various ways such as circular diagram, matters of everyday life, ball-and-stick, and STM graphic, etc. We identified two kinds of inscriptions on the basis of the possibilities of handling models: the inscriptions that represent concept of atom and molecule by image; the inscriptions that represent concept of atom and molecule by using specific matters. We analyzed the processes of interpreting inscriptions systematically with a semiotic model that includes ‘structuring processes' and ‘translating processes'. The interpretation of inscriptions representing concept of atom and molecule was a complex process requiring many steps of interpreting works. Educational implications of these findings are discussed.