• Bulletin of the Korean Chemical Society
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• v.34 no.12
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• pp.3727-3732
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• 2013

The interaction between metalloporphyrins and diazine tautomers was investigated using quantum chemistry method. The results showed that the metal atom in the metalloporphyrin was not coplanar with porphin ring, and zinc porphyrin has the most extent of its non-coplanar nature. The most stable complex in nine complexes was iron porphyrin. NBO analysis indicated that the interaction between the lone pair of electrons on the nitrogen atom and the unoccupied lone pair orbital of metal contributes significantly to the stability of the complexes. Through the conceptual DFT parameter and Fukui dual descriptor, the thermodynamic stability and reactivity of complexes were analyzed. The density difference function (DDF) analyzes were performed to explore the rearrangement of electronic density after the coordination interaction. NICS calculation indicated that metalloporphyrin aromaticity was reduced after the coordination interaction, and aromaticity of diazine tautomer was increased along direction vector of the coordination interaction force.

• Journal of Korean Biological Nursing Science
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• v.4 no.2
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• pp.41-49
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• 2002

Aim To evaluate blood pressure, blood glucose and serum lipid level in obese and nonobese type 2 diabetic patients. Methods 206 obese(76 male, 130 female) and 442 nonobese(208 male, 234 female) type 2 diabetic patients underwent fasting blood glucose, 2-hour postprandial blood glucose, $HbA_1c$ total cholesterol, triglyceride, high density lipoprotein, microalbuminuria, blood urea nitrogen, creatinine and C-peptide were measured. Diabetes was diagnosed according to the American Diabetes Association(ADA)criteria. Obesity was defined as body mass index(BMI, kilograms per meters squared)${\geq}25$. Results In male, systolic blood pressure, triglycerides, microalbuminuria and C-peptide were significant higher in obese than nonobese patients. Fasting blood glucose were significantly lower in obese than nonobese patients. Diastolic blood pressure, 2-hour postprandial blood glucose, $HbA_1c$, total cholesterol, high density lipoprotein, blood urea nitrogen, and creatinine were no difference between 2 groups. In female, triglycerides and C-peptide were significant higher in obese than nonobese patients, Blood pressure, fasting blood glucose, 2-hour postprandial blood glucose, $HbA_1c$, total cholesterol, high density lipoprotein, microalbuminuria, blood urea nitrogen, and creatinine were no difference between 2 groups. Conclusion Our present study supports that increased triglycerides play a major role in increasing the risk of coronary heart disease(CHD) in obese women type 2 diabetic patients.

• Journal of computational fluids engineering
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• v.12 no.2
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• pp.53-62
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• 2007

A high resolution numerical method aimed at solving cavitating flow is proposed and applied to gas-liquid two-phase shock tube problem. The present method employs a finite-difference 4th-order Runge-Kutta method and Roe's flux difference splitting approximation with the MUSCL TVD scheme. By applying the homogeneous equilibrium cavitation model, the present density-based numerical method permits simple treatment of the whole gas-liquid two-phase flow field, including wave propagation and large density changes. The speed of sound for gas-liquid two-phase media is derived on the basis of thermodynamic relations and compared with that by eigenvalues. By this method, a Riemann problem for Euler equations of one dimensional shock tube was computed. Numerical results such as detailed observations of shock and expansion wave propagations through the gas-liquid two-phase media at isothermal condition and some data related to computational efficiency are made. Comparisons of predicted results and exact solutions are provided and discussed.

• Advances in concrete construction
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• v.10 no.5
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• pp.431-441
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• 2020

For the purpose of improving the properties of UHPC as well as the economic efficiency in production of the material, Availability of river sands as fine aggregate instead of micro silica sand were investigated. Four different sizes of river sands were considered. Using river sand instead of micro silica sand increased the flowability, and decreased the yield stress and plastic viscosity in rheological properties, and the effect was higher with larger particle size of river sand. It was demonstrated by analyses based on the packing density. In the results of compressive strength and elastic modulus, even though river sand was not as good as micro silica sand, it could provide high strength of over 170 MPa and elastic modulus greater than 40 GPa. The difference in compressive strength depending on the size of river sand was explained with the concept of maximum paste thickness based on the packing density of aggregate. The flexural performance with river sand also presented relatively lower resistance than micro silica sand, and the reduction was greater with larger particle size of river sand. The flexural performance was proven to be also influenced by the difference in the fiber orientation distribution due to the size of river sand.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.39 no.4
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• pp.353-358
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• 1994

Grain yields of errect-leaved corn hybrids were reported to be increased as planting density(PD) increased compared to those of horizontal leaf type hybrids. This trial was conducted to investigate the difference between errect and horizontal-leaved hybrids in response to different PD. Grain yields of both type hybrids were decreased at the highest PD, however, that of horizontal-leaved hybrid, Ga209 ${\times}$ Ki14A, was decreased more than errect-leaved hybrids which indicated varietal difference in response to PD. Responses to PD for days to tasseling, plant height, ear height, and leaf angle were not significant, also, PD ${\times}$ hybrid interactions were not observed. Yield components were decreased as PD increased and there were no PD ${\times}$ hybrid interactions for these characters. Leaf angle was negatively correlated with grain yield and yield components except for kernel weight.

• 한국전산유체공학회:학술대회논문집
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• 2008.03b
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• pp.2-5
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• 2008

This study describes the numerical simulation of three-dimensional droplet formation and the following motion in a cross-junction microchannel by using the Lattice Boltzmann Method (LBM). Our aim is to develop the three-dimensional binary fluids model, consisting of two sets of distribution functions to represent the total fluid density and the density difference, which introduces the repulsive interaction consistent with a free-energy function between two fluids. We validated the LBM code with the velocity profile in a 3-dimensional rectangular channel. Then, we applied our code to the numerical simulation of a binary fluid flow in a cross-junction channel focusing on the investigation of the droplet formulation. Due to the pressure and interfacial-tension effect, one component of the fluids which is injected from one inlet is cut off into many droplets periodically by the other component which is injected from the other inlets. We considered the effect of the boundary conditions for density difference (order parameter) on the wetting of the droplet to the side walls.

• Journal of the Korean Institute of Intelligent Systems
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• v.19 no.3
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• pp.311-316
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• 2009

This paper presents the motion estimation algorithm on real-time for mobile surveillance robot using particle filter. the particle filter that based on the monte carlo's sampling method, use bayesian conditional probability model which having prior distribution probability and posterior distribution probability. However, the initial probability density was set to define randomly in the most of particle filter. In this paper, we find first the initial probability density using Sum of Absolute Difference(SAD). and we applied it in the partical filter. In result, more robust real-time estimation and tracking system on the randomly moving object was realized in the mobile surveillance robot environments.

• Nuclear Engineering and Technology
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• v.40 no.6
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• pp.477-488
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• 2008

The objective of the paper is to analyze the thermally induced density wave oscillations in water cooled boiling water reactors. A transient thermal hydraulic model is developed with a characteristics-based implicit finite-difference scheme to solve the nonlinear mass, momentum and energy conservation equations in a time-domain. A two-phase flow was simulated with a one-dimensional homogeneous equilibrium model. The model treats the boundary conditions naturally and takes into account the compressibility effect of the two-phase flow. The axial variation of the heat flux profile can also be handled with the model. Unlike the method of characteristics analysis, the present numerical model is computationally inexpensive in terms of time and works in a Eulerian coordinate system without the loss of accuracy. The model was validated against available benchmarks. The model was extended for the purpose of studying the flow-induced density wave oscillations in forced circulation and natural circulation boiling water reactors. Various parametric studies were undertaken to evaluate the model's performance under different operating conditions. Marginal stability boundaries were drawn for type-I and type-II instabilities in a dimensionless parameter space. The significance of adiabatic riser sections in different boiling reactors was analyzed in detail. The effect of the axial heat flux profile was also investigated for different boiling reactors.

• The Bulletin of The Korean Astronomical Society
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• v.41 no.1
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• pp.68.3-68.3
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• 2016

We analyze the dependence of environment of warped galaxies by using the local background density, Tidal Index and projected distance as measures of the environment. we use galaxies with redshift less than z=0.025 from the Sloan Digital Sky Survey (SDSS) DR7. We selected 345 edge-on galaxies using color images provided by the SDSS DR7 and checked it using isophotal maps. This sample contains 136 warped galaxies, 209 non-warped galaxies. Among warped galaxies, there are 18 strongly warped galaxies which have warp angles larger than 7.5o. We calculated the fractional distributions of galaxies as a function of environmental parameters. All of these parameters show little difference between warped galaxies and non-warped galaxies if we include weakly warped galaxies. However, there is a clear difference in the fractional distributions between the strongly warped galaxies and non-warped galaxies. The fraction of warped galaxies increases with decreasing distance to the nearest neighbor galaxy but It increases with increasing background density and Tidal Index. However, the relationships between warp angles and the three environmental parameters are not strong. The effect of Tidal Index is well distinguished in small, bright galaxies whereas the effects of the background density and the distance to the nearest neighbor galaxy are more pronounced in large, bright galaxies.

• Korean Journal of Food Science and Technology
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• v.20 no.2
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• pp.252-255
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• 1988

The molding characteristics, hardness and overall quality of the Korean style disposible food tray made from the low and medium density polystyene sheets were investigated and the results were obtained as follows. The volume difference of 8 sectional trays was 56.4% between the two materials, and that of 5 sectional trays was 41.8%. The more the sectional number of the tray, the larger the volume difference. Medium density polystylene tray had the better solid characteristics and overall acceptance than the low density polystlene tray.