• Proceedings of the KSME Conference
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• 2003.11a
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• pp.610-615
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• 2003

This experiment has been carried out to find the structure of turbulent boundary layer with instantaneous velocity fields obtained in stream-wall-normal planes using a stereo-PIV (Particle Image Velocimetry) method. And it has been measured perpendicular plane and horizontal plane with hairpin vortex structure by Reynolds number change and made third dimension shape for section of horizontal plane through stereo-PIV. In the outer layer hairpin vortices occur in streamwise-aligned packets that propagate with small velocity dispersion. A streaky structure is composed of counter-rotating vortex. According as y+ increases, streaky structure's interval space decrease, and it shows that hairpin shape of prior research is vertified. The objective of the present research is to gain a better understanding of coherent structures in the outer of wall turbulence by experimentally examining coherent structures.

• Proceedings of the IEEK Conference
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• 2002.07c
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• pp.1851-1854
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• 2002

The Internet with conventional routing scheme cannot meet user demands driven from drastic growth in the Internet user and various service and traffic type. MPLS(Multi Protocol Label Switching) was introduced to the Internet fur solution to resolve this problem. MPLS is a paradigm to integrate higher layer’s software routing functions including layer-3 routing with layer-2 switching. But, the exponential growth of Internet traffic brings out of label space. One scalable solution to cope with this problem is to introduce flow merge technique, i. e. a group of flows is forwarded using the same label. Specially, IETF(Internet Engineering Task Force) recommends that ATM based MPLS system may include VC merge function, so it is scalable to increase of internet traffic. We implemented the MPLS LER system that includes the look-up and forwarding function in incoming path and VC merging function and limited traffic management function in outgoing path. This paper describes the implementation of the LER’s outgoing parts.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2004.11a
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• pp.924-927
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• 2004

Measurements of fluctuating wall pressures were made with a linear array of 16 piezo-electric transducers beneath a fully-developed turbulent boundary layer. The piezoelectric bimorph actuator applied in this experiment has bonding structures of each polarity to make out-of-plane displacements rather than in-plane ones by using piezoelectric effect To specify the boundary layer characteristics at the location where the actuation was applied, the wall friction coefficients and $Re_\theta$ were measured by using the CPM method. The actuating frequency for the bimorph film was determined according to the priori bursting frequency from boundary layer parameters. The reduction of convecting energies in wave-number space was clearly observed at the specified actuating frequencies.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.34 no.12
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• pp.9-17
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• 2006

An experimental study was carried out to examine the behavior of the unsteady boundary layer. An NACA 0012 airfoil with aspect ratio of 2.7 was set vertically in a test section, which is sinusoidally pitched about the quarter chord. The oscillating amplitude is from -6$^{\circ}$ to +6$^{\circ}$ and the mean angle of attack is 0$^{\circ}$. Surface mounted probes (Glue-on probes) were employed to measure the surface flow of the boundary layer. Measurements were made at free-stream velocities of 1.98, 2.83, and 4.03m/s, and the corresponding Reynolds numbers based on the chord length were 2.3$\times$104, 3.3$\times$104 and 4.8$\times$104, respectively. The reduced frequency is fixed as 0.1 in all cases. The results show that the surface position of minimum shear stress and of boundary layer break-down can be discerned in the Reynolds number between 2.3$\times$104 and 3.3$\times$104.

• Advances in Computational Design
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• v.7 no.1
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• pp.57-68
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• 2022

A simulation study of the distribution of magnetic flux induced by a U-shaped electromagnet into a two-layer massive object with variations in the depth and properties of the surface layer has been carried out. It has been established that the hardened surface layer "pushes" the magnetic flux into the bulk of the magnetized object and the magnetic flux penetration depth monotonically increases with increasing thickness of the hardened layer. A change in the thickness and magnetic properties of the surface layer leads to a redistribution of magnetic fluxes passing between the poles of the electromagnet along with the layer and the bulk of the steel object. In this case, the change in the layer thickness significantly affects the magnitude of the tangential component of the field on the surface of the object in the interpolar space, and the change in the properties of the layer affects the magnitude of the magnetic flux in the magnetic "transducer-object" circuit. This difference in magnetic parameters can be used for selective testing of the surface hardening quality. It has been shown that the hardened layer pushes the magnetic flux into the depth of the magnetized object. The nominal depth of penetration of the flow monotonically increases with an increase in the thickness of the hardened layer.

• Journal of the Korean Society of Safety
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• v.13 no.1
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• pp.70-76
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• 1998

The smoke filling process for the atrium space containing a fire source is simulated using two types of deterministic fire models : Zone model and Field model. The zone model used is the CFAST(version 1.6) model developed at the Building and Fire Research Laboratories, NIST in the USA. The field model is a self-developed fire field model based on Computational Fluid Dynamics(CFD) theories. This article is focused on finding out the smoke movement and temperature distribution in atrium space which is cubic in shape. A computational procedure for predicting velocity and temperature distribution in fire-induced flow is based on the solution, in finite volume method and non-staggered grid system, of 3-dimensional equations for the conservation of mass, momentum, energy, species and so forth. The fire model i. e. Zone model and Field model predicted similar results for the clear height and the smoke layer temperature.

• Journal of Multimedia Information System
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• v.9 no.2
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• pp.93-102
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• 2022

Dependency parsing is a decision problem of the syntactic relation between words in a sentence. Recently, deep learning models are used for dependency parsing based on the word representations in a continuous vector space. However, it causes a mislabeled tagging problem for the proper nouns that rarely appear in the training corpus because it is difficult to express out-of-vocabulary (OOV) words in a continuous vector space. To solve the OOV problem in dependency parsing, we explored the proper noun embedding method according to the embedding unit. Before representing words in a continuous vector space, we replace the proper nouns with a special token and train them for the contextual features by using the multi-layer bidirectional LSTM. Two models of the syllable-based and morpheme-based unit are proposed for proper noun embedding and the performance of the dependency parsing is more improved in the ensemble model than each syllable and morpheme embedding model. The experimental results showed that our ensemble model improved 1.69%p in UAS and 2.17%p in LAS than the same arc-eager approach-based Malt parser.

• International Journal of Advanced Culture Technology
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• v.6 no.2
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• pp.100-106
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• 2018

Sometimes, literary therapy is to create an abscission layer at the mind and remove the signifier of love, by the abscission layer. The purpose of this study is to reveal the mechanism of literary therapy by mutation in human-created sentences and to activate literary therapy. In Gosijo, the abscission layer of Seo Gyeongdok's mind is present in the layer of the "falling leaf" of the his Sijo's last sentence, and the abscission layer of Hwang Jin-yi's mind exists in the layer of the "falling leaf" of the her Sijo's last sentence. The "falling leaf" created by the abscission layer of Seo Gyeongdok's sentence acts as an action potential to the nervous system of Hwang Jin-yi. In Hwang Jin-yi's Sijo, the abscission layer is also activated, forming a "leaf". Hwang Jin-yi's Sijo constructs a new sensory layer that is extended and mutated more than the meaning of space between lines of Seo Gyeongdok's Sijo. In her Sijo, Hwang Jin-yi twists and twists Seo Gyeongdok's sentences to squeeze the sound. She accepts the Seo Gyeongdok's sentences and twists in the first sentence and twists out of the second sentence once more to produce the mutation in the last sentence. As a result of her sentence twist, Seo Kyung-duk's visual sense of "falling leaf" is mutated into a "falling leaf's sound" of auditory sense. This mutation process works as a healing mechanism in the human body. If this study will continue in the future, it will be possible to activate literary therapy by Sijo.

• Journal of Korean Society of Steel Construction
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• v.28 no.6
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• pp.395-402
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• 2016

Space frame structures considering the components such as forms, layers, grids, etc. are possible to form a large space without interior columns. Here, steels having the yield strengths of 210 MPa to 450 MPa are generally used. The high strength steel (i.e., yield strength of 690 MPa) having suitable weldability, aseismicity and economics have been recently developed. In this paper, the high strength steel is applied to the space frame structures in order to analytically find out their transient responses considering the material and geometric nonlinearities. For various circular dome types of space frame structures, the modal analysis and nonlinear transient analysis are carried out using nonlinear three dimensional finite element analysis.

• Korean Institute of Interior Design Journal
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• v.21 no.4
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• pp.138-145
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• 2012

The epidermal color is one of factors the space for ages. Instead of the epidermal color expression, it made with material and decoration under structure for make shade of meaning before have the new media. But now a days, the epidermal color of the fashion store is getting free owe to the development of color harmony, has a great notion that gets out of the subordinate from color, and it is a emphasized factor with expression and self-control. The epidermal color of the fashion store makes an effort to accept the development and changing of new media. It should show that there role and function is changing constantly according to a new technology, and it gave a motivation for reanalysis about existence and expression of the epidermal color. The purpose of this research is that look around the feature of the epidermal color system, elements, and principle. Then contemporary fashion store is expressive characteristics of epidermal color. Using epidermal color is not common, we can find lots of the case with surface color, layer color, interface color, though. The paper reflects on the meaning and concept of fashion store which enables the application of expressive characteristics on space through advanced technology. Meanwhile, the features of epidermal color such as immateriality of process and communication can be inferred from case analysis.