• Journal of Advanced Marine Engineering and Technology
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• v.29 no.8
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• pp.849-854
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• 2005

The laminar flame concept in turbulent reacting flow is considered applicable to many practical combustion systems For turbulent premixed combustion under widely used flamelet concept, the flame surface is described as an infinitely thin propagating surface that such a Propagating front can be represented as a level contour of a continuous function G. In this study, for the Purpose of validating the LES of G-equation combustion model. LES of turbulent Premixed combustion with dynamic SGS model of G-equation in turbulent channel flow are carried out A constant density assumption is used. The Predicted flame propagating speed is goof agreement with the DNS result of G. Bruneaux et al.

• Journal of Microbiology and Biotechnology
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• v.11 no.2
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• pp.229-233
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• 2001

Trichoderma reesei Rut C-30 produced high levels of ${\beta}$-glucosidase, endo-${\beta}$-glucosidase, endo-${\beta}$-1,4-glucanase, and exo-${\beta}$-1,4-glucanase. In pilot-scale production (50-1 fermentor), productivity and yield of CMCase (carborymethyl cellulose) and FPase (filter paper activity) were 273 U/ml and 35 U/ml, and 162 FPU/l.h and 437 FPU/g, respectively. The fed-batch techniques were used to improve enzyme activities with constant cell concentration. The acidity was an important parameter and controlled at pH 3.9 and 5.0 by automatic addition of ammonium hydroxide. Cellulase powder was prepared by ammonium sulfate precipitation and its CMCase and FPase activities were 3,631 U/g and 407 U/g, respectively.

• KIEAE Journal
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• v.3 no.1
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• pp.21-29
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• 2003

Scale model measurements should be conducted under an actual sky or in a simulated sky where conditions can be held constant. A number of successful attempts have been made to develop artificial sky domes with man-made sun emulators. With reference to formerly-developed examples, sky simulator facility has recently been activated in oder to provide desirable sky conditions for teaching and studies. The structure is a 6m-diameter dome and promises to set various condition for energy related and lighting research activities. The sky dome is also equipped a heliodon, the tilt table, to facilitate additive direct sun impact under clear skies. Shading studies, using scale models with the heliodon, reveal how a building's design blocks or permits light's passage to the interior; solar access studies, and tests of the reflection and transmittance characteristics of new daylighting technologies. The design and construction specification and the initial operating experience with a building configuration are reported.

• Journal of the Korean Data and Information Science Society
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• v.26 no.3
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• pp.739-748
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• 2015

This paper deals with the problem of testing about the equality of the scale parameters in several inverse Gaussian distributions. We propose default Bayesian testing procedures for the equality of the shape parameters under the reference priors. The reference prior is usually improper which yields a calibration problem that makes the Bayes factor to be defined up to a multiplicative constant. Therefore we propose the default Bayesian testing procedures based on the fractional Bayes factor and the intrinsic Bayes factors under the reference priors. Simulation study and an example are provided.

• Advances in Computational Design
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• v.5 no.4
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• pp.349-362
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• 2020

Dynamic characteristics of a scale-dependent porous metal foam cylindrical shell under a traveling load have been explored within this article based on a numerical approach. Within the material texture of the metal foams, uniform and non-uniform porosities may be dispersed. Based upon differential quadrature method (DQM) and Laplace transforms, the equations of motion for a shear deformable scale-dependent shell may be solved numerically. Scale-dependent shell modeling has been provided based upon strain gradient elasticity. Solving the equations will give the shell deflection as a function of load speed. Also, it is reported that shell deflection relies on the porosity dispersion and strain gradient influences.

• Journal of the Korean Data and Information Science Society
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• v.26 no.6
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• pp.1501-1511
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• 2015

This paper deals with the problem of testing on the equality of the scale parameters in the log-logistic distributions. We propose default Bayesian testing procedures for the scale parameters under the reference priors. The reference prior is usually improper which yields a calibration problem that makes the Bayes factor to be defined up to a multiplicative constant. Therefore, we propose the default Bayesian testing procedures based on the fractional Bayes factor and the intrinsic Bayes factor under the reference priors. To justify proposed procedures, a simulation study is provided and also, an example is given.

• Journal of the Korean Society for Library and Information Science
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• v.32 no.2
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• pp.143-167
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• 1998

This study is to evaluate whether economies of scale exist in four categories of university libraries in the Korea. Regression analysis is used to fit a log-log equation to the total budget-output (total circulation, interlibrary lending and borrowing, reference transactions, hours opened, volumes added, automation and information indicator) for all the types of libraries. In results of the analysis, returns to scale are almost constant in the national and public libraries and larger libraries. But there is presence of economics of scale in private libraries and all of the libraries. Except for hours opened, economies of scale decrease more rapidly.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.32 no.4
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• pp.411-420
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• 1996

The structure of the scale formed on the surface of Fe - Cr - X alloys exposed to 1143K high sulfidation($Ps_2$ = 1.11$\times$$10^-7$ atm, $Po_2$ = 3.11$\times$$10^-20$ atm) or sulfidation/oxidation(($Ps_2$= 1.06$\times$$10^-7$ atm, ($Po_2$ = 3.11$\times$$10^-18$ atm) environment has been observed and analysed using XRD, SEM/EDS. To investigate the possibility of protective film formed on the surface of the alloys, Aluminium, Nickel were selected as alloying elements. Thermodynamic phase stability diagram was used to predict the reaction path of scale formed on Fe - Cr - X alloys. Parabolic rate constant($K_p$) value with 6wt% Al in Fe - 25Cr alloy decreased significantly compared with the Fe - 25Cr alloy without 6wt% Al. Since thin layer of defect free sulfide film, (Al, Cr)Sx, was formed at the alloy/scale interface. Fe - rich sulfide scale at outer layer and Cr - rich sulfide scale containing porosity at inner layer of Fe - 25Cr alloy have been observed. The reaction path for these scales could be predicted by the thermodynamic stability diagram.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.31 no.2
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• pp.94-103
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• 2008

This study measured technology transfer efficiency for public institutes. The study made use of DEA being one of the non-parametric linear programming to evaluate technology transfer efficiency for public institutes and to measure technology efficiency, pure technical efficiency and scale efficiency. The measurement of the technology transfer efficiency for public institutes was as follows: The cause of the technology transfer inefficiency was affected by pure technical inefficiency more than by scale inefficiency. Public institutes' RTS(Return To Scale) value varied depending upon the features of the organizations than the features of the regions. Public research institutes' RTS value is more effective than universities' RTS value. We compared the RTS group with the RTS of Projected DMU groups. The RTS group had constant returns to scale effect while the RTS of the Projected DMU had increasing returns to scale effect. The technology transfer efficiency of public institutes varied depending upon the features of the organizations and regions : The technology transfer efficiency of public institutes were as follows : public research institutes at the metropolitan area, public research institutes at the local areas, universities at the metropolitan area and universities at the local areas. In other words, the technology transfer efficiency was affected by organizational characteristics more than by regional characteristics at the place where public institutes were located.

• Journal of Semiconductor Engineering
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• v.1 no.1
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• pp.57-63
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• 2020

Complementary metal-oxide-semiconductor (CMOS) technology is now facing a power scaling limit to increase integration density. Since 1970s, multi-valued logic (MVL) has been considered as promising alternative to resolve power scaling challenge for increasing information density up to peta-scale level by reducing the system complexity. Over the past several decades, however, a power-scalable and mass-producible MVL technology has been absent so that MVL circuit and system implementation have been delayed. Recently, compact MVL device researches incorporating multiple-switching characteristics in a single device such as 2D heterojunction-based negative-differential resistance (NDR)/transconductance (NDT) devices and quantum-dot/superlattices-based constant intermediate current have been actively performed. Meanwhile, wafer-scale, energy-efficient and variation-tolerant ternary-CMOS (T-CMOS) technology has been demonstrated through commercial foundry. In this review paper, an overview for MVL development history including recent studies will be presented. Then, the status and its future research direction of MVL technology will be discussed focusing on the T-CMOS technology for peta-scale information processing in semiconductor chip.