• Asian Pacific Journal of Cancer Prevention
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• v.15 no.6
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• pp.2619-2623
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• 2014

Aim: To investigate signaling pathways for reversal of EGF-mediated multi-drug resistance (MDR) in hepatocellular carcinoma (HCC) models. Materials and Methods: HCC MDR cell strain HepG2/adriamycin (ADM) and SMMC7721/ADM models were established using a method of exposure to medium with ADM between low and high concentration with gradually increasing concentration. Drug sensitivity and reversal of multi-drug resistance by EGF were determined and the cell cycle distribution and apoptosis were analyzed by flow cytometry. Phosphorylation of ERK1, ERK2, ERK5 and expression of Bim were detected by Western blotting. Results: The results showed that HepG2/ADM and SMMC7721/ADM cells were resistant not only to ADM, but also to multiple anticancer drugs. When used alone, EGF had no anti-tumor activity in HepG2/ADM and SMMC7721/ADM cells in vitro, while it increased the cytotoxicity of ADM. EGF induced cell apoptosis and G0/G1 phase cell cycle arrest in HepG2/ADM And SMMC7721/ADM cells, while enhancing activity of p-ERKs and up-regulated expression of BimEL. Conclusions: EGF might enhance the chemosensitivity of HepG2/ADM and SMMC7721/ADM cells via up-regulating p-ERKs and BimEL protein.

• Nuclear Engineering and Technology
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• v.55 no.6
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• pp.2230-2245
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• 2023

KANT (KAIST Advanced Nuclear Tachygraphy) is a PWR core simulator recently developed at Korea Advance Institute of Science and Technology, which solves three-dimensional steady-state and transient multigroup neutron diffusion equations under Cartesian geometries alongside the incorporation of thermal-hydraulics feedback effect for multi-physics calculation. It utilizes the standard Nodal Expansion Method (NEM) accelerated with various Coarse Mesh Finite Difference (CMFD) methods for neutronics calculation. For thermal-hydraulics (TH) calculation, a single-phase flow model and a one-dimensional cylindrical fuel rod heat conduction model are employed. The time-dependent neutronics and TH calculations are numerically solved through an implicit Euler scheme, where a detailed coupling strategy is presented in this paper alongside a description of nodal equivalence, macroscopic depletion, and pin power reconstruction. For validation of the steady, transient, and depletion calculation with pin power reconstruction capacity of KANT, solutions for various benchmark problems are presented. The IAEA 3-D PWR and 4-group KOEBERG problems were considered for the steady-state reactor benchmark problem. For transient calculations, LMW (Lagenbuch, Maurer and Werner) LWR and NEACRP 3-D PWR benchmarks were solved, where the latter problem includes thermal-hydraulics feedback. For macroscopic depletion with pin power reconstruction, a small PWR problem modified with KAIST benchmark model was solved. For validation of the multi-physics analysis capability of KANT concerning large-sized PWRs, the BEAVRS Cycle1 benchmark has been considered. It was found that KANT solutions are accurate and consistent compared to other published works.

• Journal of the Korean housing association
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• v.20 no.4
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• pp.79-88
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• 2009

A planned access method on constantly-changing-community unit plan changes and develops based on the periodical situation and also plan theory. In this research, it is to present the link between the theory of complex city change and the plan factor of it, and to show how Korean residential complex plan has changed as time passed and how new concept of city plan came up and by applying new methods how can this affect our real world and the past plan. In the phase of analysis, it analyzed the flow of 'community unit plan' and its theory and investigated the factor of compositional space and built a analysis frame. The factors of community unit plan are space structure, size and shape of block, population, distribution of facilities and movement system. It chose the place that can represent the flow of community unit plan trand and that indicates the obvious development leading to Jamsil (1975), Gwa Chun (1980), Mok Dong (1983), Sang Ge (1985), Ilsan (1989), Dong tan (2001) and Eun Jung (2003) total of 7 places. And to compare a similar size of the city, it selected a small community unit. Based on the result of theoretical study and prior research, it can be said that the space composition style has change from a whole complete complex area to a linked-cross over community unit and the access of urban level was on set. Also, a pedestrian walking area was secured and the dense of building structure and pleasant environment wanting need was in balance. For facility plans, the usage of facility and functional change brought change of type, size and disposition. The walking area for pedestrian became a huge matter. Therefore, market, education, public facilities and green system collaborated to co-build a whole community unit and activated the walking environment. Also, public transportation, environment friendly city organization was built.

• Journal of the Korean Society of Marine Environment & Safety
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• v.22 no.6
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• pp.750-757
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• 2016

This study presents the wave run-up height around single and multiple surface-piercing cylinders according to wave period and steepness. In order to simulate 3D incompressible viscous two-phase turbulent flow, the present study employed a volume of fluid (VOF) method with realizable $k-{\varepsilon}$ turbulence model based on commercial Computational Fluid Dynamics (CFD) software, "STAR-CCM". The wave periods at model scale were 1.269s and 1.692s for a single cylinder and 1.716s for multiple cylinders. In each case, wave steepness of has 1/30 and 1/16 were used, respectively. Consequently, the results for wave run-up height with regard to wave steepness and period were compared with those of relevant previous experimental studies. The numerical simulation results showed a good qualitative agreement with experiments.

• Journal of computational fluids engineering
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• v.21 no.3
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• pp.15-23
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• 2016

In the present study, two phase flows around a projectile vertically launched from an underwater platform have been numerically investigated by using a three dimensional multi-phase RANS flow solver based on pseudo-compressibility and a homogeneous mixture model on unstructured meshes. The relative motion between the platform and projectile was described by six degrees of freedom equations of motion with Euler angles and a chimera technique. The propulsive power of the projectile was modeled as the fluid force acting on the lower surface of the body by the compressed air emitted from the underwater platform. Various flow conditions were considered to analyze the fluid-dynamics motion parameters of the projectile. The water level of platform and the current speed around the projectile were the main parametric variables. The numerical calculations were conducted up to 0.75sec in physical time scale. The dynamics tendency of the projectile was almost identical with respect to the water level variation due to the constant buoyancy term. The moving speed of the projectile along the vertical axis inside the platform decreased when the current speed increased. This is because the inflow from outside of the platform impeded development of the compressed air emitted from the floor surface of the launch platform. As a result, the fluid force acting on the lower surface of the projectile decreased, and injection time of the projectile from the platform was delayed.

• 한국전산유체공학회:학술대회논문집
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• 2010.05a
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• pp.479-486
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• 2010

Using the numerical code for the interior ballistics, the performance of the interior ballistics with the characteristics according to the position of the solid propellant in chamber has been investigated. In existing research, propellants have been evenly distributed in the chamber. In this study, however, several cases of the existence of empty space in the chamber at which the propellants are not evenly distributed are considered. The 7-perforated propellant configuration has been used in this research. The results have shown the change of performance of the interior ballistics according to solid propellant positions in the chamber.

• Journal of computational fluids engineering
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• v.15 no.4
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• pp.17-24
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• 2010

Using the numerical code for the interior ballistics, the performance of the interior ballistics with the characteristics according to the position of the solid propellant in chamber has been investigated. In existing research, propellants have been evenly distributed in the chamber. In this study, however, several cases of the existence of empty space in the chamber at which the propellants are not evenly distributed are considered. The 7-perforated propellant configuration has been used in this research. The results have shown the change of performance of the interior ballistics according to solid propellant positions in the chamber.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.48 no.7
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• pp.839-846
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• 1999

This paper presents an efficient algorithm for determining the location, size and number of capacitors in unbalanced radial distribution system. The objective function formulated consists of two terms: cost for energy loss and cost related to capacitor purchase and capacitor installation. The cost function associated with capacitor placement is considered as step function due to banks of standard discrete capacities. Genetic algorithms(GA) are used to obtain the population is derived. The strings in each population consist of the bus number index and size of capacitors to be installed. In order to determine the number of capacitor placement, the length mutation operator is used. Its efficiency is proved through the application in unbalanced radial distribution systems made of 10 buses with 9 distribution lines and 25 buses with 24 distribution lines.

• KIEE International Transactions on Electrophysics and Applications
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• v.5C no.5
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• pp.204-210
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• 2005

Alternating current (AC) losses of two Bi-2223 ([Bi, Pb]: Sr: Ca: Cu: O = 2:2:2:3) tapes [(Tape I, un-twist-pitch) and the other with a twist-pitch of 10 mm (Tape II)] were measured and compared. These samples, produced by the powder-in-(Ag) tube (PIT) method, are multi-filamentary. Also, it's produced by non-twist and different twist pitch (8, 10, 13, 30, 50 and 70 mm). The critical current measurement was carried out under the environment in liquid Nitrogen and in zero-field by 4-probe method. Susceptibility measurements were conducted while cooling in a magnetic field. Flux loss measurements were conducted as a function of ramping rate, frequency and field direction. The AC flux loss increases as the twist-pitch of the tapes decreased, in agreement with the Norris Equation. Neutron-diffraction measurements have been carried out investigate the crystal structure, magnetic structures, and magnetic phase transitions in Bi-2223([Bi, Pb]:Sr:Ca:Cu:O)

• The KSFM Journal of Fluid Machinery
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• v.7 no.6 s.27
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• pp.55-61
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• 2004

A numerical procedure for optimizing the shape of three-dimensional sedimentation tank is presented to maximize its sedimentation efficiency. The response surface based optimization is used as an optimization technique with Reynolds-averaged Navier-Stokes analysis for multi-phase flow. Standard $k-{\epsilon}$ model is used as a turbulence closure. Three design variables such as, tank height to center feed wall diameter ratio, blockage ratio of center feed wall and angle of distributor are chosen as design variables. Sedimentation efficiency is defined as an objective function. Full-factorial method is used to determine the training points as a means of design of experiment. Sensitivity of each design variable on the objective function has been evaluated. And, optimal values of the design variables have been obtained.