• Proceedings of the Korean Institute of Building Construction Conference
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• 2016.05a
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• pp.253-254
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• 2016

In the trend of building enlargement, high-rise and irregular shaped building, domestic application of BIM in construction phase is increasing in recent years. BIM that is based on a three-dimensional, requires a specific building expression. Model expression level required for each phase such as design, construction, and maintenance of the construction project can be different. BIM model to apply in practice is difficult because it is not clear to set up the criteria for the expression level of construction BIM model. And it has a limit that is lower productivity in construction project. Therefore, this study considers the way of the improvement and analyzes the application for representation level of construction BIM model through the survey. By analyzing of the survey results, this study will be to present a basis for an appropriate expression level setting of construction BIM model.

• Korean Journal of Veterinary Research
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• v.40 no.2
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• pp.333-337
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• 2000

This experiment was done to observe the pathological findings of lymphocystis naturally occurred in the cultured flounders in the southern sea of Korea. Anatomical sign of lymphocystis was characterized by the presence of wart-like nodules on the fins, body surface and mouth. Dense clustering of hypertrophic cells originated from fibroblasts was observed in the lesions. Infected hypertrophic cells had a thick hyaline capsule, large vesiculated nucleus with irregular rims and large nucleolus, and large ribbon-shaped basophilic inclusions at the peripheral zone of the cytoplasm. Hexagonal virus particles with the two layers of capsid were scattered throughout the cytoplasm and were absent from the inclusions.

• Korean Journal of Ichthyology
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• v.20 no.1
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• pp.70-73
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• 2008

Eight specimens (330.2~431.3 mm TL) of the family Zoarcidae were collected from the costal waters of the Byeonsanbando, Yellow Sea, Korea. They were identified as a Zoarces elongatus Kner based on the following characters: a dorsal fin with 14~16 notch-shaped spinous rays, irregular 13~16 dark spots in a row along the median body and 126~132 vertebrae. We proposed a new Korean name, 'Mu-jeom-deung-ga-si-chi', for the species.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.14 no.6
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• pp.68-73
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• 2005

Tire manufactures have dealt with noise problem by varying the pitch of the tread. The various formulas for the variations are generally determined differently, however. Often these variations are based on a combination of trial and error, intuition, and economics. Some manufactures have models and analogs to test tread patterns and their variations. These efforts, however practical, do not determine the best variation beforehand or guarantee the best results. For this reason it was felt that a general mathematical approach fur determining the best variation was needed. Moreover, the method should be completely general, easy to use, and sufficiently accurate. This paper discusses a mathematical method called Mechanical Frequency Modulation(MFM) which meets the above requirements. Thus, MFM pertains to computing an irregular time sequence of events so that the resulting excitation spectrum is shaped to a preferred form. The first part of this paper treats the theoretical basis for computing an optimum variation ; the second part discusses experimental results and simulation program which corroborate the theory.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1990.04a
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• pp.65-69
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• 1990

The elastic analysis of floor slabs using the p-version of finite element method encounters stress singularities at certain types of reentrant corners, openings and cut-outs. Results obtained using the computer code based on C$\^$o/-hierarchic plate element formulated by Reissner-Mindlin theory are compared with theoretical predictions and with computational results reported in the literature. The convergence rate of h-, p- and hp-version can be estimated on the basis of the energy norm in global sense. If accuracy in terns of the number of degrees-of-freedom is used as a criterion, the solutions presented here are the most efficient that have been published up to date. Examples are the rhombic plate with the obtuse angle of 150o and the square plate with cut-outs.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2010.04a
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• pp.384-387
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• 2010

비정형 초고층 구조시스템 통합설계 플랫폼은 비정형 초고층건물의 구조시스템 설계를 지원하는 여러프로그램들을 통합적으로 활용하여 구조설계자들이 협업을 수행하는 체계이다. 이 체계의 핵심적인 사항은 각 프로그램들이 필요한 자료들을 신속하고 정확하게 교환하는 것이다. 표준자료모델은 여러 프로그램들의 자료교환을 목적으로 적절한 범위 내에서 필요한 자료들을 취합하여 체계화한 것이다. 하지만 표준자료모델은 각 프로그램에서 요구되는 모든 자료들을 취합하고 그 목적에 부합되도록 체계화시킬 수 없어 문제가 발생한다. 이에 본 연구에서는 비정형 초고층건물 구조시스템 통합설계 플랫폼의 각 프로그램들이 표준 자료모델을 이용하여 자료를 교환하는 방법을 검토하고 비교하고자 한다.

• Journal of the Korean institute of surface engineering
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• v.26 no.5
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• pp.225-234
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• 1993

Titanium nitride coatings were deposited onto SUS304 stainless steel substrates pretreated by mechanical scrubbing, chemical etching at 50% HCl solution and Ar ion etching. Adhesion strength were measured by scratch tester and confirmed by SEM with EDS. Adhesion strength of Ar ion etched substrate was 10 to 15 times higher than that of mechanical scrubbed or chemical etched substrate. Ar ion etching brought about an uniform and fine spherical shaped surface, while chemical etching gave rise to a rough and irregular surface on SEM micrograph. It was suggested that higher adhesion strength might be caused by anchoring effect of Ar ion etched surface prior to TiN deposition.

• Journal of Advanced Marine Engineering and Technology
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• v.23 no.2
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• pp.176-183
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• 1999

This paper is aimed to investigate behaviour of vortex in 2-D step cavity with high Reynolds numbers$(3.2{\times}10^{3},\;10^{4},\;3{\times}10^{4},\;5{\times}10^{4}\;and\;7{\times}10^{4})$. The SOLA algorithm which is MAC type was adopted to solution method computing the flow field on irregular grid. In case of $Re=7{\times}10^{4}$ flow behavior is steady bu periodic unsteady sinusoidal fluctuation of local velocity and kinetic energy is found for $Re=10^{4}$ Continuous movements of small eddies in the secondary flow regions are discov-ered for $3{\times}10^{4}$ Generation of eddies and their active migrating behavior are detected over $Re=5{\times}10^{4}$ resulting in complete unsteady and non-linear flow characteristics Furthermore a typhoon-like vortex(TLV) appears intermittently and rotates along the separation regions and boundary layers.

• Korean Journal of Metals and Materials
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• v.46 no.8
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• pp.506-515
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• 2008

Recently, it is exceedingly required to produce metal powders with tailored shape and phase altogether in order to fabricate high performance functional parts such as magnetic core or electro-magnetic noise suppressor for high frequency usage. Therefore, the collision phenomena of in-flight droplets against chamber wall or neighboring in-flight droplets each other is investigated by a computational method in order to get useful information about how to design the atomizing system and how to tailor process parameters not to make irregular-shaped powders during gas atomization process. As a results, smaller powders, lower melt temperature are known to be favorable for droplets not to collide against chamber wall. In additions, powders of narrower size distribution range, lower droplet generation rate, lower melt temperature, lower gas velocity are desirable to prevent droplet-collisions against neighboring in-flight droplets.

• Korean Journal of Metals and Materials
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• v.47 no.3
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• pp.182-187
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• 2009

The molten salt electrolysis is applied to reduce titanium dioxide to titanium metal using calcium chloride as an electrolyte and the reaction mechanism of the reduction process is examined by analyzing the reaction products. The process conditions to obtain titanium metal for $900^{\circ}C$ correspond to 2.9~3.2 V and 24 hours. The reaction products for 2.9 V at $900^{\circ}C$ include irregular-shaped titanium oxides such as $Ti_4O_7$, $Ti_3O_5$ and $Ti_2O_3$ and polyhedral $CaTiO_3$. Using these microstructure analysis, the sequential reaction mechanism for the electrochemical reduction of titanium dioxide to titanium is proposed.