• The Korean Journal of Food And Nutrition
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• v.23 no.1
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• pp.8-14
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• 2010

This study was carried out to develop an optimum baking formula and baking process for a new bread raw material with added Cordyceps militaris powder, which has been known to prevent various adult diseases and cancers. The rheological properities of dough made from Cordyceps militaris powder-wheat flour with 0, 1, 2, and 3% Cordyceps militaris powder added-were investigated. A farinogram showed that the water absorption and weakness value of dough increased with added Cordyceps militaris powder, but development time and dough stability were decreased. An extensogram showed that resistance to extension was increased in bread with 1% Cordyceps militaris powder, but decreased in bread with 2% and, 3% powder. Extensibility decreased fermentation progressed. An amylogram showed that gelatinization point was increased but maximum viscosity was decreased with added Cordyceps militaris powder. With increased amounts of powder dough volume during fermentation was reduced. The change in pH values of dough after mixing, fermentation, and proofing decreased with increased amounts of added powder.

• Proceedings of the Korea Concrete Institute Conference
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• 1997.10a
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• pp.369-374
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• 1997

This study is the experimental results on the flowing properties of the super flowing concrete (SFC) using limestone (LS), which is to develop the SFC in level of ordinary strength. And this study is described with respect to basic concept, confined water ratio ($\beta_p$) of binder (cement+limestone) in paste, relationship between volume ratio of water-binder (w/b) and addition ratio of superplasticizer in mortar, flowing velocity and funneling time and compressive strength in concrete to replacement ratio of LS. The results of this study is improved to flowing properties in fleshly concrete with increasing replacement ratio of LS. The optimal mixing condition of the SFC using LS in level of ordinary strength is proved W/C 55%, LS 40% and W/C 60%, LS 50%.

• 한국전산유체공학회:학술대회논문집
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• 2005.04a
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• pp.85-90
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• 2005

The heat transfer enhancement by pulsatile flow in plate heat exchanger has been investigated numerically in the present study. The numerical study was performed ill the range of the Strouhal number from 0.04 to 2 and the Reynolds number from 370 to 730. The results showed that the pulsatile flow produces resonating vortex shedding at the groove sharp edges and a strong transient vortex rotation within the grooved channels. As a result, the mixing between the trapped volume in the grooved cavity and the main stream was enhanced. Good agreements between the predictions and measured data are obtained for the optimum frequency of pulsation and corresponding heat transfer enhancement

• Transactions of the Korean Society of Mechanical Engineers B
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• v.24 no.6
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• pp.777-784
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• 2000

A Navier-Stokes code based on an unstructured finite volume method is used to simulate the MIT flapping foil experiment. A low Reynolds number ${\kappa}-{\varepsilon}$ turbulence model is used to close the Reynolds averaged Navier-Stokes equations. Computations are carried out for the whole experimental domain involving two flapping foils and a downstream hydrofoil. The computational domain is meshed with unstructured quadrilateral elements, partly structured. Numerical solutions show good agreement with experiment. The first harmonics of the velocity in the boundary layer shows local peak value inside the boundary layer and also local minimum near the edge of boundary layer. It is intensified as it develops along the blade surface. This is shown to be caused as the unsteadiness inside the boundary layer is being convected at a speed less than the free stream value. It is also shown that there is negligible mixing of the unsteadiness between the boundary layer and the free stream.

• Journal of computational fluids engineering
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• v.10 no.2
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• pp.21-29
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• 2005

In this paper, we present the theoretical and numerical results of scavenge characteristics in a small subchamber of an HCCI(Homogeneous Charge Compression Ignition) engine. Two theoretical models are proposed in prediction of the scavenge time and the efficiency; one is the non-mixing model in which the input gas(CH4) and the existing gas(air) do not mix at all, and the other is the fully-mixed model in which the two gases are assumed to mix completely before ejection. Focus is also given to the effect on the scavenge performance of the size of the chamber outlet.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2017.05a
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• pp.71-72
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• 2017

The oyster shell is lightweight and exhibits strength characteristics similar to sand. In this study, mortar specimens were fabricated by crushing them and processed to 5mm or less of the fine aggregate standard, and examined the fire resistance of the mortar according to changes in particle size distribution. In this experiment, seven particle size distribution conditions were tested. In addition, the mixing ratio was fixed at 1: 3, and the experiment was conducted in terms of the volume ratio because the densities of sand and oyster shells were different.

• Journal of the Korean Society of Combustion
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• v.14 no.2
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• pp.32-41
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• 2009

The transported probability density function model combined with the consistent finite volume (FV) method has been applied to simulate the turbulent bluff-body reacting flows. To realistically account for the non-isotropic turbulence effects on the turbulent bluff-body reacting flows, the present PDF transport approach is based on the joint velocity- turbulent frequency-composition PDF formulation. The evolution of the fluctuating velocity of a particle is modeled by a simplified Langevin equation and the particle turbulence frequency is represented by the modified Jayesh - Pope model. Effects of molecular diffusion are represented by the interaction by exchange with the mean (IEM) mixing model. To validate this hybrid FV/PDF transport model, the numerical results are compared with experimental data for the turbulent bluff-body reacting flows.

• 한국연소학회:학술대회논문집
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• 2006.04a
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• pp.218-222
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• 2006

Due to the high density and heating value, liquid fuel is attractive for ramjet propulsion system. Liquid fuel requires time to evaporation and mix with incoming air before ignition; insufficient evaporation and mixing result in low combustion efficiency and instability. So the numerical studies are conducted to investigate the spray and combustion characteristics of a liquid-fueled dump type Ramjet combustor. The governing equations are solved by means of a finite-volume using time derivative preconditioning method for chemical reacting flow. The liquid phase is treated by solving Lagrangian equations of motion and transport for the life histories of a statistically significant sample of individual droplets.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2003.04a
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• pp.337-339
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• 2003

The technology removing radionuclides from soil using soil washing was studied. The main radionuclides contaminated in the soil are Cs$^{137}$ and Co$^{60}$ . It is suitable that scrubbing time is 4 hours and a mixing ratio of soil weight and washing solution volume is 1:10. more than two times continuous scrubbing method with 0.5 M oxalic acid was needed to remove Cs$^{137}$ and Co$^{60}$ from soil more than 70%. Radionuclides removal efficiencies of recycling washing solutions recycled with strong acid resins until 5 times are similar to that of 0.5 M oxalic acid.

• Water Engineering Research
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• v.1 no.3
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• pp.171-185
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• 2000

A mathematical model to adequately predict complex mixing characteristics of sorptive polluants in natural streams with pools-and-riffes has been developed. In this model, sorption of pollutants onto the bed sediment as well as mass storage and exchange in the storage zones were incorporated into one-dimensional mass balance equatins. The geometric and hydraulic characteristics of the pool-riffle sequences were properly conceptualized. Simulations with parameters of pool-and-riffle streams better fit the measured data in overall shape and peak concentration than simulations with parameters for uniform channels. The analyses on the characteristics of the storage zone model parameters reveal that a linear relationship between the logrithm of the storage zone volume ratio and a function of the friction factor exists. A linear relatiohship might also be tenatively assumed between the logarithm of the dimensionless mass exchange coefficient and the logarithm of the aspect ratio of the storage zone if some of the high values of the dimensionless mass exchange coefficient collected on the successive bed forms are excluded.