• Proceedings of the KIEE Conference
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• 2005.05a
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• pp.134-136
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• 2005

This paper deals with the standard logic symbols with which the engineer will design the control strategy and loop for the utility boiler of the next generation thermal power plant For this purpose, we review the existing international standards for logic symbols. which include ISO, ANSI, and older SAMA. From this review, it is possible to design the standard logic symbol that will be used in the following design phase. The designed standard logic symbols are supposed to provide the logic design with independence from the specific hardware that will be employed in the phase of construction.

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.188-188
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• 2006

We demonstrate two very simple and fast routes to fabricating ordered micro/nanopatterns of polymers over large areas on various substrates using controlled dewetting. The first method is based on utilizing microimprinting to induce the local thickness variation of an initially inverted bilayer which allows the controlled dewetting and partial layer inversion upon subsequent thermal annealing. In the second method, the self assembly of block copolymer was controlled on a chemically micropatterned surface produced by microcontact printing, being combined with its solvent vapor treatment. The kinetically driven, non-lithographical nanopattern structures were easily fabricated over large area by these approaches.

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.269-269
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• 2006

The molecular structure of poly(2,6-dimethyl-4,4' -phenylene oxide)-g-poly (styrenesulfonic acid) (PPO-g-PSSA) graft copolymer was designed, and synthesized via living radical polymerization. Obtained graft copolymers were transformed into proton exchange membranes for direct methanol fuel cell (DMFC) application. The performance of the membranes was measured in terms of water uptake, proton conductivity, methanol permeability, and thermal stability. Very low methanol permeability and good proton conductivity were observed by adjusting grafting frequency and PSSA block content.

• Proceedings of the Korea Concrete Institute Conference
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• 1995.10a
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• pp.329-333
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• 1995

The usual methods for the temperature control of mass-concrete structures include the use of low-heat cement, pre-cooling, or pipe-cooling. In order to control the heat of hydration of mass-concrete structures such as massive pier or anchor block, and mat foundation, the pipe cooling method is widely acceptable for pratical use. In this paper, method of analysis using the Finite Element Method was applied to analyze the heat exchange on the field of three dimensional thermal conduction. The result of analysis Well agreed with experimentally measurement data by "KUMATANI". The method of this analysis will be used widely to control the heat of hydration by the pipe cooling in mass-concrete.-concrete.

• Transactions of the Korean hydrogen and new energy society
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• v.28 no.3
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• pp.246-251
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• 2017

To fabricate a hydrocarbon polymer electrolyte composite membrane incorporated with Pt nanoparticle, the polymer electrolyte membrane made of a sulfonated-fluorinated hydrophilic-hydrophobic block copolymer (SFBC) and sulfonated poly (ether ether ketone) (SPEEK) blend in the wight ratio of 1 : 1 was synthesized, and a simple drying process was used in order to incorporate Pt nanoparticle into the SFBC/SPEEK film by reducing platinum (II) bis (acetylacetonate), Pt $(acac)_2$. The distribution of the Pt nanoparticles was observed by transmission electron microscopy (TEM), and mechanical and thermal properties were tested by universal testing machine (UTM) and thermogravimetry analyzer (TGA). Cation conductivity, ion exchange capacity (IEC) and I-V characteristics were estimated.

• Journal of computational fluids engineering
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• v.18 no.3
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• pp.87-93
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• 2013

A computational study has been performed to examine the effects of catalytic walls on the stagnation region heat transfer. The boundary conditions for none, finite, and fully catalytic walls have been incorporated into a multi-block compressible Navier-Stokes solver. In the present study, both chemical and thermal non-equilibrium effects were included. The flows over a blunt body model were simulated by varying surface catalytic recombination rates. A full range of catalycities was explored in the context of a constant wall temperature assumption. Detailed information on species concentrations, temperature, and surface heat flux are presented. Comparison with available flight data of surface heat flux is also made.

• Journal of Welding and Joining
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• v.31 no.3
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• pp.54-59
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• 2013

Several methodologies analyzing welding distortions of large shell structures like ship blocks have been developed and utilized in shipyards for a long times ago. In general, one of objects of thermal distortion analysis is to find welding sequence making least-deformation without any suppliance, and it can be solved easily and rapidly by EP strain-boundary method. But after assembly construction, there are usually more than 10 weldments in each process, and the number of sequence will follow the Factorial calculation. In this research, a method has been suggested to decide the best welding sequence by minimum analysis. Using this method, welding deformation could be reduced just analyzing some cases as many as the number of weldments. Experiments and Analysis of all cases were also done, and their best results are good agreements with predictation by suggested methodology.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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• pp.6-6
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• 2011

Graphene, a monlayer of carbon atoms arrange to form a 2-dimensional honeycomb lattice, exhibits enormous fascinating properties, such as a linear energy dispersion relation, a wide-range optical absorption, high thermal conductivity, and mechanical flexibility [1]. Because the unique material properties of graphene allow it to be a promising building block for the next generation electronic and optoelectronic devices, sometimes graphene-based devices have refereed to be a strong candidate to overcome the intrinsic limitations of conventional semiconductor-based technology [2,3]. However, there are several fundamental or technological hurdles to be overcome in real applications of graphene in electronics and optoelectronics. In this tutorial we will present a short introduction to the basic materials properties and recent progress in applications of graphene and discuss future outlook of graphene-based electronic and optoelectronic devices.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2011.11a
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• pp.48-51
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• 2011

본 논문은 나사조임 단자대 내에 접속되는 전선의 접촉불량에 따른 발열특성을 분석하고자 단자대 접속개소의 조임토크를 KS C 2625에서 규정한 정상조임토크와 인위적인 불량조임토크를 변수로 설정하여 조임토크의 크기별로 동일한 부하를 인가한 후, 열화상카메라를 이용하여 접속불량에 따른 발열특성을 비교 분석하였다.

• Proceedings of the Membrane Society of Korea Conference
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• 2004.05b
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• pp.57-60
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• 2004

Polymer electrolyte membranes have been studied widely in chloro-alkali electrolysis, cationic exchange resins, and fuel cell applications. Especially, sulfonated polyimide membranes have been suggested as a potential polymer electrolyte in PEMFC due to their excellent thermal stability and high proton conductivity.(omitted)