• Journal of the Korean Society of Manufacturing Process Engineers
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• v.10 no.6
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• pp.140-145
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• 2011

An anisotropic beam model is proposed by employing an asymptotic expansion method for thermo-mechanical multiphysics environment. An asymptotic method based on virtual work is introduced first, and then the variables of mechanical displacement and temperature rise are asymptotically expanded by taking advantage of geometrical slenderness of elastic bodies. Subsequently substituting these expansions into the virtual work principle allows us to asymptotically expand the virtual work. This will yield a set of recursive virtual works from which two-dimensional microscopic and one-dimensional macroscopic equations are systematically derived at each order. In this way, homogenized stiffnesses and thermomechanical coupling coefficients are derived. To demonstrate the validity and efficiency of the proposed approach, composite beams are taken as a test-bed example. The results obtained herein are compared to those of three-dimensional finite element analysis.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.60 no.3
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• pp.486-491
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• 2011

Since Korea has high accident rate for the electrical shock than other advanced countries, it causes very serious problems. In this paper, a new classification method for analyzing electricity accidents is proposed, which is based on the microscopic view while existing methods have been based at the macroscopic view point. Electrical accidents cases can be mainly divided by three cases, which are from live works, incompleteness of the grounding system and imperfectness of the safety education and public relations. New data format of electrical shocks are proposed in the environment of smart grids.

• Applied Microscopy
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• v.46 no.4
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• pp.171-175
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• 2016

A distinctive neuronal network in the brain is believed to make us unique individuals. Electron microscopy is a valuable tool for examining ultrastructural characteristics of neurons, synapses, and subcellular organelles. A recent technological breakthrough in volume electron microscopy allows large-scale circuit reconstruction of the nervous system with unprecedented detail. Serial-section electron microscopy-previously the domain of specialists-became automated with the advent of innovative systems such as the focused ion beam and serial block-face scanning electron microscopes and the automated tape-collecting ultramicrotome. Further advances in microscopic design and instrumentation are also available, which allow the reconstruction of unprecedentedly large volumes of brain tissue at high speed. The recent introduction of correlative light and electron microscopy will help to identify specific neural circuits associated with behavioral characteristics and revolutionize our understanding of how the brain works.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.02a
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• pp.404-404
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• 2010

Despite much works have been done on the geometric structures of ripples, defects and edge atoms in a graphene device, there has been no report showing the direct correlation between the structures and the transport property. Unlike scanning tunneling microscopy or other electron microscopes, Scanning Gate Microscope (SGM) is a unique microscopic tool with which the local electronic structure and the transport property of a device can be measured simultaneously. We have performed a transport measurement in nanometer scale using a scanning gate microscope (SGM). We have found the nanoscopic pictures of electron and hole puddles and the role of graphene- device edges in the transport measurements. These experimental findings were successfully explained with a theoretical model.

• Transactions of the Korean Society of Mechanical Engineers
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• v.15 no.1
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• pp.107-119
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• 1991

This dissertation analyzes the running mechanism of flexible and thin tape above rotating head through the experiment. The scope of study is confined to measure the vertical deformation of running tape under hydrodynamic pressure invoking phenomena of elasto-hydrodynamic lubrication between the protruded bump on a rotating cylinder ad the running tape. Experimental system is devised to measure the vertical deflection of the running tape by opto-electronical displacement gauge, which enables to detect microscopic surface deflection of high frequency. Thorough the tests of small specimens of groove and bump, the accuracy and reliability of this experimental method is confirmed and achieved an accuracy within 5%(2.mu.m) error for the microscopic deflection with high frequency. In experimental works, the effects of bump size on flying characteristics of the tape were evaluated and examined. For the vertical deformation of the running tape. the numerical results and its trend agree qualitatively with the experimental ones.

• Journal of the Korean Ceramic Society
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• v.43 no.2 s.285
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• pp.69-73
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• 2006

A full retention of the tetragonal phase with coarse grains $(50\~60\;{\mu}m)$ was possible with the specimen $ZrO_2-1.9\;mol\%\;Y_2O_3$. In these coarse grains, $\{101\}_t$ annealing twins were frequently observed, although they do not exist in the usual fine grained specimens. The morphology and growth rate of the isothermally formed individual products are studied at an optical microscopic level. The habit planes of both products are also identified by performing two-surface trace analysis on the grains whose orientations are determined by the Electron Back Scattering Pattern (EBSP) method. The morphologies of isothermal martensite were well-defined thin plates and lenticular types. The growth rate in their longitudinal directions was quite slow and temperature-dependent. A two-surface trace analysis, incorporated with the EBSP method, identified the habit planes near $\{013\}_c$, in agreement with previous reports obtained from TEM works.

• Journal of ILASS-Korea
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• v.11 no.4
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• pp.212-219
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• 2006

The initial film flow development of the high-pressure swirl spray was investigated at different injector operating conditions to analyze film flow development and to provide the input data for the modeling works. This result can be also useful to verify the previously simulated results. The initial flow conditions such as liquid film thickness, flow angle and flow divergence are obtained by visualizing the inside and near the nozzle flow with a microscopic imaging system. The visualized images are quantified using an image processing tool. From the information of liquid film thickness and flow angle, the initial axial and tangential velocity and the swirl number of the swirl spray are successfully determined at various operating conditions. The experimental results showed that the initial liquid film thickness, flow angle and flow divergence are remained constant when the injection pressure is increased. However, initial film conditions are severely changed when the fuel temperature is increased. The swirl number remained constant when the injection pressure is increased while it showed increased value at high fuel temperature condition.

• Cartoon and Animation Studies
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• s.37
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• pp.267-286
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• 2014

Yeon Sang-Ho's Animation occupies an exceptional place in Korean Animation, being categorized as the kind of realism representing the pitiable actuality rather than the liberal and creative imagination. His animation appreciated as 'stories much more real than the reality' mainly depicts the world of 'the others' who resides on the periphery of the society in a rough and straightforward way. Yeon Sang-Ho's Animation represents the emotions and desire of characters as well as the heartless real world refusing the fantasy, through which it reflects the portraits of people living in post-capitalistic era seen from the microscopic view. This article investigates the textual characteristics, defining his animation as the Brutal history of 'The Others'. Two conditions which constitute the actual world in his works are the absurd social system and the characters who are afflicted with the trauma, belonging to the lower classes. Therefore, the landscape of real life which contains vicious victim, corrupted monster and being as 'homo sacer' looks like a painting of hell. Yeon Sang-Ho's Animation summons the shadow of ourselves which has been negated or neglected through the figure of 'the others' produced in post-capitalistic era and exposes our bare face and the uncomfortable truth by displaying the affected area of out society plainly. Furthermore, his works demonstrate the possibility of Korean animation as a representational language of facing the reality and searching for the truth.

• Development and Reproduction
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• v.18 no.2
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• pp.107-115
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• 2014

Cardiovascular system is the primary organ to develop and reach a functional state, which underscores the essential role of the vasculature in the developing embryo. The vasculature is a highly specialized organ that functions in a number of key physiological works including the carrying of oxygen and nutrients to tissues. It is closely involved in the formation of heart, and hence it is essential for survival during the hatching period. The expression of genes involved during vascular development in the olive flounder (Paralichthys olivaceus) in the days after hatching is not fully understood. Therefore, we examined the expression patterns of genes activated during the development of flounder. Microscopic observations showed that formation of blood vessels is related to the expression of the vimentin gene. Also, the temporal expression patterns of this vimentin-like gene in the developmental stages and in the normal tissues of olive flounder. The purpose of this study was to examine the expression patterns of vimentin in normal tissues of the olive flounder and during the development of the vascular system in newly hatched olive flounders and HIF-1 plays a vital role in the formation of blood vessels during development. Vimentin expression was strong at the beginning of the development of blood vessels, and was present throughout all developmental stages. Our findings have important implications with respect to the roles of vimentin and HIF-1 in the development and evolution of the first blood vessels in olive flounder. Further studies are required to elucidate the vimentin-mediated hypoxic response signal transduction and to decipher the functional role of vimentin in developmental stages.

• Applied Microscopy
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• v.40 no.1
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• pp.47-51
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• 2010

The capability of real-time observation in TEM is quite useful to study dynamic phenomena of materials in a certain variable ambience. In performing the experiment, the choice of video recording program is an important factor to obtain high quality of movie streaming. Window Movie Maker (WMM) is generally recommended as a default video recording program if one uses "DV Capture" function in DigitalMicrograph$^{TM}$ (DM) software. However, the image quality does not often satisfy the condition for high-resolution microscopic analysis since the severe information loss in the final result occurs during the conversion process. As a good candidate to overcome this problem, Virtual-Dub is highly recommended since the information loss can be minimized through the streaming process. In this report, we demonstrated how useful VirtualDub works in a high-resolution movie recording. Quantitative comparison of the information quality between the images recorded by each software, WMM and VirtualDub, was carried out based on histogram analysis. As a result, the image recorded by VirtualDub was improved ~13% in brightness and ~122% in contrast compared with the image obtained by WMM at the same imaging condition. Remarkably, the gray gradation (meaning an amount of information) becomes wider up to ~115% than that of the WMM result.