• Transactions on Electrical and Electronic Materials
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• v.17 no.2
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• pp.98-103
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• 2016

The surface morphology of the front transparent conductive oxide (TCO) films plays a vital role in amorphous silicon thin film solar cells (a-Si TFSCs) due to their high transparency, conductivity and excellent light scattering properties. Recently, plasma textured glass surface morphologies received much attention for light trapping in a-Si TFSCs. We report various plasma textured glass surface morphologies for the high efficiency of a-Si TFSCs. Plasma textured glass surface morphologies showed high rms roughness, haze ratio with micro- and nano size surface features and are proposed for future high efficiency of a-Si TFSCs.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2012.10a
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• pp.1023-1025
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• 2012

Solar energy is rapidly gaining notoriety as an important means of expanding renewable energy resources. As such, it is vital that those in engineering fields understand the technologies associated with this area. My project will include the design and construction of a microcontroller-based solar panel tracking system. Solar tracking allows more energy to be produced because the solar array is able to remain aligned to the sun. This system builds upon topics learned in this course. Performance and usefulness of a solar tracking device that was designed and produced in this study was confirmed through experiments.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2017.05a
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• pp.126-126
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• 2017

Using first principles calculations we unveil fundamental mechanism of hydrolysis reactions of two hazardous chemicals $PCl_3$ and $POCl_3$ with molecular water clusters nearby. It is found that the water molecules play a key role as a catalyst significantly lowing the activation barriers by transferring its protons to the reaction intermediates. Interestingly, torsional angles of molecular complexes at transition states are identified as a vital descriptor on the reaction rate. Analysis of charge distribution over the complexes further reinforces the finding with atomic level correlation between the torsional angle and variation of the orbital hybridization state of P in the complex. Electronic charge separation (or polarization) enhances thermodynamic stability of the activated complex at transition state and reduces the activation energy through hydrogen bonding network with water molecules nearby. Calculated potential energy surfaces (PES) for the hydrolysis reactions of $PCl_3$ and $POCl_3$ depict their two contrastingly different profiles of double- and triple-deep wells, respectively. It is ascribed to the unique double-bonding O=P in the $POCl_3$. Our results on the activation free energy show well agreements with previous experimental data within $7kcalmol^{-1}$ deviation.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.2
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• pp.271-280
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• 2020

The study aims to provide some evidence of the effects of CSR practices on financial-based brand equity in Malaysia. Nowadays, many companies have embraced corporate social responsibility (CSR) practices because CSR is a vital component of the current competitive and complex business arena. It contributes greatly to social, environmental, and economic condition. With CSR practices, companies are able to achieve many benefits and there is evidence that CSR practices predict higher brand equity. However, little evidence has been produced concerning the effects of CSR practices on financial aspects of brand equity in developing countries such as Malaysia. Therefore, this paper aims to investigate the effects of CSR practices on financial based brand equity among Malaysia Top 100 brand. A CSR checklist instrument was used in the current study to examine the extent of CSR practiced. The results indicated that PLCs that were actively involved in CSR practices such as environmental, community, workplace and marketplace, found that this involvement enhanced their brand equity. The findings provide useful support and evidence for the management of PLCs in Malaysia, as well as companies in other developing countries, to engage more in CSR practices as a core element of their strategic and brand management.

• Journal of Magnetics
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• v.16 no.3
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• pp.246-252
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• 2011

A high-voltage power supply has been built for activation of the brain via stimulation using a Full Wave Cockroft-Walton Circuit (FWCW). A resonant half-bridge inverter was applied (with half plus/half minus DC voltage) through a bidirectional power transistor to a magnetic stimulation device with the capability of producing a variety of pulse forms. The energy obtained from the previous stage runs the transformer and FW-CW, and the current pulse coming from the pulse-forming circuit is transmitted to a stimulation coil device. In addition, the residual energy in each circuit will again generate stimulation pulses through the transformer. In particular, the bidirectional device modifies the control mode of the stimulation coil to which the current that exceeds the rated current is applied, consequently controlling the output voltage as a constant current mode. Since a serial resonant half-bridge has less switching loss and is able to reduce parasitic capacitance, a device, which can simultaneously change the charging voltage of the energy-storage condenser and the pulse repetition rate, could be implemented. Image processing of the brain activity was implemented using a graphical user interface (GUI) through a data mining technique (data mining) after measuring the vital signs separated from the frequencies of EEG and ECG spectra obtained from the pulse stimulation using a 90S8535 chip (AMTEL Corporation).

• Journal of Integrative Natural Science
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• v.9 no.3
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• pp.166-170
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• 2016

Collagen plays a vital role in the maintenance of structure and function of a human body. It has been widely applied in various fields including biomedical, cosmeceutical, food, pharmaceutical and tissue engineering. In the present study, the docking behaviour of type I collagen with 15 different ligands namely hydroxymethylfurfural, methylglyoxal, methylsyringate, O-methoxyacetophenone, 3-phenyllactic acid, 4-hydroxybenzoic acid, kojic acid, lumichrome, galangin, artoindonesianin F, caffeic acid, 4-coumaric acid, origanol A, thymoquinone and quercetin was evaluated along with their putative binding sites using Discovery Studio Version 3.1. Docking studies and binding free energy calculations revealed that origanol A has maximum interaction energy (-40.48 kcal/mol) and quercetin with the least interaction energy (-15.44 kcal/mol) as compared to the other investigated ligands. Three ligands which are galangin, methylsyringate and origanol A were shown to interact with Asp21 amino acid residue of chain B (type I collagen). Therefore, it is strongly suggested that the outcomes from the present study might provide new insight in understanding these 15 ligands as potential type I collagen modulators for the prevention of collagen associate disorders.

• Nuclear Engineering and Technology
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• v.53 no.10
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• pp.3359-3366
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• 2021

An engineered barrier system (EBS) for the deep geological disposal of high-level radioactive waste (HLW) is composed of a disposal canister, buffer material, gap-filling material, and backfill material. As the buffer fills the empty space between the disposal canisters and the near-field rock mass, heat energy from the canisters is released to the surrounding buffer material. It is vital that this heat energy is rapidly dissipated to the near-field rock mass, and thus the thermal conductivity of the buffer is a key parameter to consider when evaluating the safety of the overall disposal system. Therefore, to take into consideration the sizeable amount of heat being released from such canisters, this study investigated the thermal conductivity of Korean compacted bentonites and its variation within a temperature range of 25 ℃ to 80-90 ℃. As a result, thermal conductivity increased by 5-20% as the temperature increased. Furthermore, temperature had a greater effect under higher degrees of saturation and a lower impact under higher dry densities. This study also conducted a regression analysis with 147 sets of data to estimate the thermal conductivity of the compacted bentonite considering the initial dry density, water content, and variations in temperature. Furthermore, the Kriging method was adopted to establish an uncertainty metamodel of thermal conductivity to verify the regression model. The R² value of the regression model was 0.925, and the regression model and metamodel showed similar results.

• Geomechanics and Engineering
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• v.18 no.1
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• pp.97-109
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• 2019

Physical conditions play vital role on the mechanical properties of frozen soil, especially for the temperature and moisture content of frozen soil. Subsequently, they influence the subsidence and stress law of permafrost layer. Taking Jiangcang No. 1 Coal Mine as engineering background, combined with laboratory experiment, field measurements and empirical formula to obtain the mechanical parameters of frozen soil, the thick plate mechanical model of permafrost was established to evaluate the safety of permafrost roof. At the same time, $FLAC^{3D}$ was used to study the influence of temperature and moisture content on the deformation and stress law of frozen soil layer. The results show that the failure tensile stress of frozen soil is larger than the maximum tensile stress of permafrost roof occurring in the process of mining. It indicates that the permafrost roof cannot collapse under the conditions of moisture content in the range from 20% to 27% as well as temperature in the range from $-35^{\circ}C$ to $-15^{\circ}C$. Moreover, the maximum subsidence of the upper and lower boundary of the overlying permafrost layer decreases with the increase of moisture content in the range of 15% to 27% or the decrease of temperature in the range of $-35^{\circ}C$ to $-15^{\circ}C$ if the temperature or moisture content keeps consistent with $-25^{\circ}C$ or 20%, respectively.

• Membrane Journal
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• v.30 no.6
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• pp.359-372
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• 2020

Compared to other oil/water separation methods, oil/water separation membranes have low energy costs and higher performance levels. Superhydrophilicity and underwater superoleophobicity are factors that are most vital in developing effective oil/water separation membrane. In addition, antifouling property and biodegradability are also factors that have to be considered in developing the membranes. In this review, studies which have enhanced the oil/water separation efficiency by modifying the chemistry and morphology of the surface of the membrane are discussed.

• Steel and Composite Structures
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• v.38 no.5
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• pp.583-597
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• 2021

This article develops a nonclassical model to analyze bending response of squared perforated microbeams considering the coupled effect of microstructure and surface stress under different loading and boundary conditions, those are not be studied before. The corresponding material and geometrical characteristics of regularly squared perforated beams relative to fully filled beam are obtained analytically. The modified couple stress and the modified Gurtin-Murdoch surface elasticity models are adopted to incorporate the microstructure as well as the surface energy effects. The differential equations of equilibrium including the Poisson's effect are derived based on minimum potential energy. Exact closed form solution is obtained for bending behavior of the proposed model considering the classical and nonclassical boundary conditions for both uniformly distributed and concentrated loads. The proposed model is verified with results available in the literature. Influences of the microstructure length scale parameter, surface energy, beam thickness, boundary and loading conditions on the bending behavior of perforated microbeams are investigated. It is observed that microstructure and surface parameters are vital in investigation of the bending behavior of perforated microbeams. The obtained results are supportive for the design, analysis and manufacturing of perforated nanobeams that commonly used in nanoactuators, nanoswitches, MEMS and NEMS systems.