• 천문학회보
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• 제41권1호
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• pp.72.1-72.1
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• 2016

Current and planned large-volume surveys such as the Sloan Digital Sky Survey extended Baryon Oscillation Spectroscopic Survey (SDSS IV-eBOSS) or the Dark Energy Spectroscopic Instrument (DESI) will use Luminous Red Galaxies (LRGs) and Emission Line Galaxies (ELGs) to map the cosmic web up to z~1.7, and will allow one to accurately constrain cosmological models and obtain crucial information on the nature of dark energy and the expansion history of the Universe in novel epochs - particularly by measuring the Baryon Acoustic Oscillation (BAO) feature with improved accuracy. To this end, we present here a study of the spatial distribution and clustering of a sample of LRGs and ELGs obtained from a sub-volume of the MultiDark simulation complemented by different semi-analytic prescriptions, and investigate how these two different populations trace the cosmic web at different redshift intervals - along with their synergy. This is the first step towards the interpretation of upcoming ELG and LRG data.

• 오토저널
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• 제5권4호
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• pp.47-61
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• 1983

In this paper the simulation of a thermodynamic power cycle for a 4-stroke, single-cylinder, spark-ignition engine was studied. In this simulation the cylinder volume was restricted to two zones, a burnt and an unburnt zone, and the convective heat transfer from cylinder contents to surroundings was considered. The chemical species in burnt gas considered was 12 species including H$_{2}$O, H$_{2}$, OH, H, N$_{2}$, NO, N, CO$_{2}$, CO, $O_{2}$, O and Ar. Using this model, computer program for compression, ignition and expansion processes was composed and pressure, temperature and composition of cylinder gas at each crank angle were computed. The composition of CO$_{2}$, CO, $O_{2}$ in the burnt gas when exhaust valve opens, the maximum temperature, the maximum flame speed and the combustion duration were also computed as a function of equivalence ratio. The relation between burnt mass fraction and burnt volume fraction was also computed.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2005년도 추계학술대회논문집
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• pp.475-478
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• 2005

Calculation of wear depth with regard to the wear topology is peformed numerically Four typical wear topology, that is round, crescent, flat, and diamond types are adopted to represent the configuration of wear volume. Diamond and flat types are the most severe topology for wear depth history, whereas round and crescent types have small increasing rate of wear depth to the wear volume. Based on this study we can guess that the most severe wear phenomena happens to be upper side of U-tubes in the KSNP SG, because flat or diamond wear will be generated by the wearing motion between tubes and diagonal, vertical, horizontal strips. The misalignment of tube at the stage of manufacturing or distortion of upper structure due to the thermal expansion or vibration of upper structure such as diagonal, vertical, and horizontal strips will be one of the main causes of flat or diamond wear.

• 천문학회보
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• 제44권1호
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• pp.57.1-57.1
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• 2019

In support of current and upcoming large-volume cosmological surveys such as the SDSS-IV eBOSS, LSST, and DESI, we present an extensive suite of high-resolution cosmological hydrodynamical simulations spanning a large range of cosmological and astrophysical parameters. We follow the evolution of gas, dark matter, neutrinos, and dark radiation, and consider several combinations of box sizes and number of particles - enhancing the resolution up to $3{\times}33283=110$ billion particles in a (100 h-1 Mpc)3 box size. We also provide 100,000 skewers for a variety of redshift slices and combination of cosmological and astrophysical parameters, useful for interpreting upcoming high-quality $Lyman-{\alpha}$ forest data. These novel simulations represent an improvement over our previous runs, and can be useful for a broader variety of cosmological and astrophysical applications, ranging from the three-dimensional modeling of the $Lyman-{\alpha}$ forest to cross-correlations between different probes, for studying the expansion history of the Universe including massive neutrinos, and for particle-physics related topics.

• 한국가시화정보학회지
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• 제18권3호
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• pp.35-41
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• 2020

We conduct numerical simulations of the interaction of a deformable structure with two-phase compressible flow. The finite volume method (FVM) is used to simulate fluid phenomena including a shock wave, a gas bubble, and the deformation of free surface. The deformation of a floating structure is computed with the finite element method (FEM). The compressible two-phase volume of fluid (VOF) method is used for the generation and development of a cavitation bubble, and the immersed boundary method (IBM) is used to impose the effect of the structure on the fluid domain. The result of the simulation shows the generation of a shock wave, and the expansion of the bubble. Also, the deformation of the structure due to the hydrodynamic loading by the explosion is identified.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 1999년도 학술대회논문집-국제 전기방전 및 플라즈마 심포지엄 Proceedings of 1999 KIIEE Annual Conference-International Symposium of Electrical Discharge and Plasma
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• pp.29-39
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• 1999

Both conventional and PI3 implanters require dense sources for high productivity rate, and small sheath expansion in PI3 besides. The problem of the creation of large volume uniform plasma in PI3 facilities replaces that of beam forming in accelerators. Some aspects of ion extraction in both cases and Langmuir probe plasma diagnostics with be discussed. Plasma parameters of large volume multicusp dc hot cathode and inductively coupled RF plasma sources obtained with Langmuir probe and ion mass analyzer with be presented. Design features and performances of high current Freeman and ECR ion sources will be described.

• 한국복합재료학회:학술대회논문집
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• 한국복합재료학회 2003년도 추계학술발표대회 논문집
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• pp.217-220
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• 2003

The effective thermoelastic properties of porous metals are discussed herein after each material forming process such as hot pressing or extrusion. The voids in metal matrix are assumed to be initially spherical in shape and to be distributed randomly. Once the porous material deforms plastically due to each material forming process, the voids change their shape from a sphere to an ellipsoid and align in one direction. Since the voids are compressible in nature, the void volume fraction is assumed to be decreasing during each material forming process.

• 한국농촌생활과학회지
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• 제7권1호
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• pp.31-37
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• 1996

This experiment was carried out in order to investigate milling methods of rice flours on characteristics of rice-cinnamon cakes. The expansion ratio and cake volume of hydrated rice flour was the better than the non-hydrated rice flours. The rice-cinnamon cake of the hydrated riceflour was generally alike in texture and taste to the cake of wheat flour as the result of Instron and sensory evaluation. The rice - cinnamon cake of the non - hydrated rice flour was generally lower in aircell and texture to the cake of the hydrated rile flour.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.I
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• pp.217-220
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• 2005

To find the optimal expansion of the color gamut of a display, we investigated various 4-primary display systems based on DLP. Via comparing the volume of the color gamut in a 3-D uniform color space CIELUV, the best 4-primary system on the premise of keeping the existing three primaries is brought forward.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제52권8호
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• pp.342-347
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• 2003

The suspension insulators are subjected to harsh environment in service for a long time. Long term reliability of the insulators is required for both mechanical and electrical performances. We studied an analysing method to find out a deformation of brittle porcelain with a thermal expansion of simulation analysis and experimental results show that cement volume growths affect severely to b mechanical failure ageing.