• Current Photovoltaic Research
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• v.11 no.4
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• pp.114-117
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• 2023

Transparent Photovoltaic (PV) modules have recently been in the spotlight because they can be applied to buildings and vehicles. However, crystalline silicon (c-Si) solar modules, which account for about 90% of the PV module market, have the disadvantage of applying transparent PV modules due to their unique opacity. Recently, a see-through type PV module using a crystalline silicon solar strap has been developed. However, there is a problem due to a decrease in aesthetics due to the metal ribbon in the center of the see-through type PV module and difficulty bonding the metal ribbon due to the low voltage output of the strap. In this study, to solve this problem, we developed a fabrication process of series connected c-Si solar strap cells using the c-Si solar cells. We succeeded in fabricating a series connected strap with a width of 2-10 mm, and we plan to manufacture an aesthetic see-through type c-Si PV module.

• Polymer Science and Technology
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• v.24 no.5
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• pp.512-516
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• 2013

• Nuclear Engineering and Technology
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• v.44 no.6
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• pp.673-682
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• 2012

Three dimensional atom probe tomography (3D APT) is applied to characterize the dissimilar metal joint which was welded between the Ni-based alloy, Alloy 690 and the low alloy steel, A533 Gr. B, with Alloy 152 filler metal. While there is some difficulty in preparing the specimen for the analysis, the 3D APT has a truly quantitative analytical capability to characterize nanometer scale particles in metallic materials, thus its application to the microstructural analysis in multi-component metallic materials provides critical information on the mechanism of nanoscale microstructural evolution. In this study, the procedure for 3D APT specimen preparation was established, and those for dissimilar metal weld interface were prepared near the fusion boundary by a focused ion beam. The result of the analysis in this study showed the precipitation of chromium carbides near the fusion boundary between A533 Gr. B and Alloy 152.

• Nuclear Engineering and Technology
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• v.44 no.5
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• pp.491-500
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• 2012

The dissimilar metal joints welded between Ni-based alloy, Alloy 690 and low alloy steel, A533 Gr. B with Alloy 152 filler metal were characterized by using optical microscope, scanning electron microscope, transmission electron microscope, secondary ion mass spectrometry and 3-dimensional atom probe tomography. It was found that in the weld root region, the weld was divided into several regions including unmixed zone in Ni-base alloy, fusion boundary, and heat-affected zone in the low alloy steel. The result of nanostructural and nanochemical analyses in this study showed the non-homogeneous distribution of elements with higher Fe but lower Mn, Ni and Cr in A533 Gr. B compared with Alloy 152, and the precipitation of carbides near the fusion boundary.

• Nuclear Engineering and Technology
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• v.44 no.4
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• pp.429-436
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• 2012

Critical heat flux (CHF) is the thermal limit of a phenomenon in which a phase change occurs during heating (such as bubbles forming on a metal surface used to heat water), which suddenly decreases the heat transfer efficiency, thus causing localized overheating of the heating surface. The enhancement of CHF can increase the safety margins and allow operation at higher heat fluxes; thus, it can increase the economy. A very interesting characteristic of nanofluids is their ability to significantly enhance the CHF. Nanofluids are nanotechnology-based colloidal dispersions engineered through the stable suspension of nanoparticles. All experiments were performed in round tubes with an inner diameter of 0.01041 m and a length of 0.5 m under low pressure and low flow (LPLF) conditions at a fixed inlet temperature using water, 0.01 vol.% $Al_2O_3$/water nanofluid, and SiC/water nanofluid. It was found that the CHF of the nanofluids was enhanced and the CHF of the SiC/water nanofluid was more enhanced than that of the $Al_2O_3$/water nanofluid.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.08a
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• pp.229-229
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• 2010

We report a high crystalline nonpolar a-plane (11-20) GaN on r-plane (1-102) sapphire substrates with $+0.15^{\circ}$, $-0.15^{\circ}$, $+0.2^{\circ}$, $-0.2^{\circ}$ and $+0.4^{\circ}$ misoriented by metalorganic chemical-vapor deposition (MOCVD). The multi-quantum wells (MQWs) active region is consists of 5 periods the nonpolar a-plane InGaN/GaN (a-InGaN/GaN) on a high quality a-plane GaN (a-GaN) template grown by using the multibuffer layer technique. The full widths at half maximum (FWHMs) of x-ray rocking curve (XRC) obtained from phiscan of the specimen that was grown up to nonpolar a-plane GaN layers with double crystal x-ray diffraction. The FWHM values of $+0.4^{\circ}$ misoriented sapphire substrate were decreased down to 426 arc sec for $0^{\circ}$ and 531 arc sec for $-90^{\circ}$, respectively. Also, the samples were characterized by photoluminescence (PL).

• Bulletin of the Korean Chemical Society
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• v.34 no.4
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• pp.1296-1299
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• 2013

• Journal of the Architectural Institute of Korea Structure & Construction
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• v.34 no.8
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• pp.13-18
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• 2018

The purpose of this study was to study on the estimation of green remodeling energy reduction tool in building construction. Green Remodeling Decision System that can predict the energy reduction effect in green remodeling is developed as a tool for simple remodeling of green remodeling considering users' convenience, so that it can quickly and comprehensively determine power peak load reduction factor technology. A preliminary simulation result of a short preliminary remodeling evaluation is DB. It will be developed as a tool that can be easily accessed by users such as web and apps.

• Journal of the Korea Institute of Military Science and Technology
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• v.14 no.2
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• pp.246-263
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• 2011

Mankind has just begun to recognize that the most crucial factor to achieve the sustainable society in the future is green technology. Most countries support the development of green technology to prevent catastrophes from global warming, mainly in the areas of reducing carbon dioxide from the atmosphere. However, most products we consume in everyday life are produced through chemical processes, and we often oversee the fact that the huge amount of waste and energy during these chemical processes will seriously influence our goal to achieve our future society sustainable. Thus the technologies to minimize the amount of disposed waste and energy consumption during chemical processes may be more important than to reduce the greenhouse gases. In this regard this review introduces the recent status of green chemistry and future prospects in order to help our chemists and engineers establish research projects based on the green chemistry principles.

• STI Policy Review
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• v.4 no.1
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• pp.135-161
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• 2013

This paper examines Japan's Science and Technology (S&T) Basic Plans in accordance with its S&T Basic Law. The Basic Plans promote two major innovation (Green Innovation and Life Innovation) towards the creation of new markets and jobs, specifically under the Fourth S&T Basic Plan enacted on August 2011. Successful smart community demonstration projects at four urban localities were launched under plans to promote Green Innovation research and development of renewable energy technologies. However, the expectation that renewable energy such as solar or wind power can replace nuclear power is not backed by sufficient evidence. Furthermore, the electricity produced by these sources is expensive and unstable owing to its reliance on weather conditions. The Fukushima nuclear power plant accident on March 2011 has also seriously affected Japan's future energy plans. According to a government estimate, electricity charges would double if nuclear power generation were abandoned, imposing a heavy burden on the Japanese economy. Japan is in need of energy policies designed on the basis of more far-sighted initiatives.