• Transactions of the Korean Society of Automotive Engineers
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• v.5 no.1
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• pp.87-100
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• 1997

The ability of turbulence model to accurately describe the complex characteristics of the flow field and the fuel spray is of great importance in the optimum design of diesel engine. The numerical simulations of the flow field and the spray characteristics within the combustion chamber of direct injection model entgine are performed to examine the applicability of turbulence model. The turbulence models used are the RNG $\varepsilon$ model and the modified $\varepsilon$ model which included the compressibility effect due to the compression/expansion of the charges. In this study, the predicted results in the quiescent condition of direct injection model engine show reasonable trends comparing with the experimental data of spray characteristics, i. e., spray tip penetration, spray tip velocity. The results of eddy viscosity obtained using the $\varepsilon$ model in the spray region is significantly larger than that obtained using the RNG $\varepsilon$ model. The application of the RNG model seems to have some potential for the simulations of the spray characteristics, e. g., spray tip penetration, spray tip velocity, droplets distribution over the $\varepsilon$ model.

• Journal of Electrical Engineering and information Science
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• v.2 no.5
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• pp.17-26
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• 1997

Interconnect characterization on a wafer level was performed. Test patterns for single, two-coupled, and triple-coupled lines ere designed by using 0.5$\mu\textrm{m}$ CMOS process. Then interconnect capacitances and resistances were experimentally extracted by using tow port network measurements, Particularly to eliminate parasitic effects, the Y-parameter de-embedding was performed with specially designed de-embedding patterns. Also, for the purpose of comparisons, capacitance matrices were calculated by using the existing CAD model and field-solver-based commercial simulator, METAL and MEDICI. This work experimentally verifies that existing CAD models or parameter extraction may have large deviation from real values. The signal transient simulation with the experimental data and other methodologies such as field-solver-based simulation and existing model was performed. as expected, the significantly affect on the signal delay and crosstalk. The signal delay due to interconnects dominates the sub-micron-based a gate delay (e.g., inverter). Particularly, coupling capacitance deviation is so large (about more than 45% in the worst case) that signal integrity cannot e guaranteed with the existing methodologies. The characterization methodologies of this paper can be very usefully employed for the signal integrity verification or he electrical design rule establishments of IC interconnects in the industry.

• International Journal of Ocean System Engineering
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• v.3 no.2
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• pp.68-76
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• 2013

In this study, a 3D numerical model was used to predict nonlinear wave forces on a cylindrical pile installed in a shallow water region. The model was based on solving the viscous and incompressible Navier-Stokes equations for a two-phase flow (water and air) model and the volume of fluid method for treating the free surface of water. A new application was developed based on the cut-cell method to allow easy installation of complicated obstacles (e.g., bottom geometry and cylindrical pile) in a computational domain. Free-surface elevation, water particle velocities, and inline wave forces were calculated, and the results show good agreement with experimental data obtained by the Danish Hydraulic Institute. The simulation results revealed that the proposed model can, without the use of empirical formulas (i.e., Morison equation) and additional wave analysis models, reliably predict non-linear wave forces on an offshore wind turbine foundation installed in a shallow water region.

• Computers and Concrete
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• v.20 no.6
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• pp.645-654
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• 2017

Continuing from previous studies of sustainable concrete containing environmentally friendly materials and existing modeling approach to predicting concrete properties, this study developed an estimation methodology to predicting the strength of sustainable concrete using an advanced case-based reasoning approach. It was conducted in two steps: (i) establishment of a case database and (ii) development of an advanced case-based reasoning model. Through the experimental studies, a total of 144 observations for concrete compressive strength and tensile strength were established to develop the estimation model. As a result, the prediction accuracy of the A-CBR model (i.e., 95.214% for compressive strength and 92.448% for tensile strength) performed superior to other conventional methodologies (e.g., basic case-based reasoning and artificial neural network models). The developed methodology provides an alternative approach in predicting concrete properties and could be further extended to the future research area in durability of sustainable concrete.

• International Journal of Advanced Culture Technology
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• v.10 no.3
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• pp.127-145
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• 2022

Vaccine diplomacy is a manifestation of competition for political influence among great powers amidst the Covid-19 pandemic's blatant illustration of ineluctable interdependency across the global community. The reinforcement of trends bolstering global polity construction intensify concomitantly with nationalist populist value and attitude expressions increasing political polarization. The interdependency graphically illustrated in the Cold War-era's mutual assured destruction incentivized competition into indirect competitive intervention in the internal politics of third actors. Indirect international influence contestations included extended, de facto challenge competitions to generate soft power on behalf of the victor, e.g., the space race. The Covid-19 pandemic has intensified this competition to offer alternative development models while intense domestic political polarization undermines the mobilizational capacities for achieving sustainable development. In contrast to multinational and multiethnic states, nation states have an inherent mobilizational advantage because of the enhanced control capabilities available to the authorities without emphasizing coercion. Control through Gramscian hegemonic mechanisms is more readily feasible in nation states through the greater feasibility of commodification of social relations by states authorities regulating and channeling social competition to encourage social mobility and creativity. The regulation of the so-called private sector serves to manage and contain social competition while channeling it to develop the institutional capacities for control and allocation of developing societal human resources. It enhances developed state control mechanisms and international influence capacities. The appeal of offers of aid and assistance to the so-called developing world becomes ever more urgent amidst Anthropocene crises including its most recent, current Covid-19 pandemic disaster.

• IMMUNE NETWORK
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• v.20 no.4
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• pp.29.1-29.20
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• 2020

The development of refractory tumor cells limits therapeutic efficacy in cancer by activating mechanisms that promote cellular proliferation, migration, invasion, metastasis, and survival. Benzimidazole anthelmintics have broad-spectrum action to remove parasites both in human and veterinary medicine. In addition to being antiparasitic agents, benzimidazole anthelmintics are known to exert anticancer activities, such as the disruption of microtubule polymerization, the induction of apoptosis, cell cycle (G2/M) arrest, anti-angiogenesis, and blockage of glucose transport. These antitumorigenic effects even extend to cancer cells resistant to approved therapies and when in combination with conventional therapeutics, enhance anticancer efficacy and hold promise as adjuvants. Above all, these anthelmintics may offer a broad, safe spectrum to treat cancer, as demonstrated by their long history of use as antiparasitic agents. The present review summarizes central literature regarding the anticancer effects of benzimidazole anthelmintics, including albendazole, parbendazole, fenbendazole, mebendazole, oxibendazole, oxfendazole, ricobendazole, and flubendazole in cancer cell lines, animal tumor models, and clinical trials. This review provides valuable information on how to improve the quality of life in patients with cancers by increasing the treatment options and decreasing side effects from conventional therapy.

• Korean Journal of Food Science and Technology
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• v.22 no.5
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• pp.575-581
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• 1990

The existence of the equivalent point for a thermal processing system was demonstrated using arbitrarily chosen ideal direct heating curves. i.e. isothermal heating curves at $120^{\circ}C$ for 10min and at $135^{\circ}C$ for 10sec. Under these conditions, G-values and F-values were calculated at various values of Ea- and z-values by applying the Arrhenius and the Bigelow models respectively. The equivalent time and equivalent temperature were determined by both line intersection and linear regression methods. The equivalent points estimated by both the line intersection and the linear regression methods were consistent and their values were the same as the heating time and temperature of the ideal direct heating curves.

• Food Science of Animal Resources
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• v.41 no.2
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• pp.288-299
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• 2021

Biofilm formation of Geobacillus thermodenitrificans, Geobacillus thermoglucosidans and Anoxybacillus flavithermus in milk on stainless steel were monitored at 55℃, 60℃, and 65℃ for various incubation times. Although species of Geobacillus showed a rapid response and produced biofilm within 4 h on stainless steel, a delay (lag time) was observed for Anoxybacillus. A hyperbolic equation and a hyperbolic equation with lag could be used to describe the biofilm formation of Geobacillus and Anoxybacillus, respectively. The highest biofilm formation amount was obtained at 60℃ for both Geobacillus and Anoxybacillus. However, the biofilm formation rates indicated that the lowest rates of formation were obtained at 60℃ for Geobacillus. Moreover, biofilm formation rates of G. thermodenitrificans (1.2-1.6 Log10CFU/mL∙h) were higher than G. thermoglucosidans (0.4-0.7 Log10CFU/mL∙h). Although A. flavithermus had the highest formation rate values (2.7-3.6 Log10CFU/mL∙h), this was attained after the lag period (4 or 5 h). This study revealed that modeling could be used to describe the biofilm formation of thermophilic bacilli in milk.

• Journal of the Korean Society for Heat Treatment
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• v.36 no.6
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• pp.396-401
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• 2023

Aus-tempering heat treatment is suitable for thin and small-sized in precision parts. However, the heat treatment process relies on the experience and skill of the operator, making it challenging to produce precision parts due to the cold forging process. The aims of this study is to explore suitable machine learning models using data from the aus-tempering heat treatment process and analyze the factors that significantly impact the mechanic properties (e.g. hardness). As a result, the study analyzed, from a machine learning perspective, how hardness prediction varies based on the quenching temperature, carbon (C), and copper (Cu) contents.

• Journal of Life Science
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• v.25 no.9
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• pp.1014-1020
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• 2015

This study suggests that fermented rice bran extract contains natural antioxidants. The contents of bioactive materials (e.g., polyphenolic compounds and flavonoids), antioxidative properties (DPPH (α,α'- diphenyl-β-picrylhydrazyl) free radical scavenging activity, Fe reducing, Cu reducing power, peroxidation of linoleic acid and rat hepatocyte microsome) were tested by in vitro experimental models using fermented rice bran (FRB) extract. The concentrations of phenolic compound and flavonoid were 19.92 mg/g and 11.56 mg/g, respectively. In oxidation in vitro models using DPPH free radical scavenging activity, (free radical scavenging activity 69.8%) Fe reducing power and Cu reducing power (effect of dose-dependent manner), Fe²⁺/ascorbate induced linolenic acid peroxidation by ferric thiocyanate and thiobarbituric acid (TBA) methods (inhibition activity 81%), and autooxidation of rat hepatic microsomes membrane (lipid peroxidation inhibition activity 38%), antioxidative activities were stronger in FRB extract than FRS (Fermented Rice and Soybean, positive control) extract and, these effects were dose-dependent manner. From these results, FRB extract was shown to have the most potent antioxidative properties and contain the highest amounts of antioxidative compounds such as phenolic compounds and flavonoids. Overall, these results may provide the basic data to understand the antioxidative properties of fermented rice bran for development of functional foods.