• Nuclear Engineering and Technology
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• v.52 no.11
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• pp.2581-2584
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• 2020

Boron has been considered to play a nutritionally important role in humans and animals, but its biochemical functions are not clearly understood. Though there are signs that boron affects the mineral and hormone metabolisms, there is no comprehensive epidemiological evidence establishing a relationship between a boron intake and osteoporosis due to the excretion of calcium in the bones. In this study, we investigated the influence of boron intake on the calcium excretion of old female mice in the menopause. The concentrations of calcium in backbone, thigh bone, blood, kidney, liver, and spleen were investigated by using instrumental neutron activation analysis.

• Transactions of the Korean hydrogen and new energy society
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• v.34 no.6
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• pp.581-586
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• 2023

As the development of alternative energy is required due to the depletion of fossil fuels, interest in the use of hydrogen energy is increasing. Hydrogen is a promising clean energy source with high energy density and can lead to the application of environmentally friendly technologies. However, due to difficulties in production, storage, and transportation that prevent the application of hydrogen-based eco-friendly technology, research on reforming reactions using dimethyl ether (DME) is being conducted. Unlike other hydrocarbons, DME is attracting attention as a hydrogen carrier because it has excellent storage stability and transportability, and there is no C-C bond in the molecule. The reaction between DME and steam is one of the reforming processes with the highest hydrogen yield in theory at a temperature lower than that of other hydrocarbons. In this study, a hydrogen reforming device using DME was developed and a catalyst prepared by supporting Cu in alumina was put into a reactor to find optimal hydrogen production conditions for supplying hydrogen to fuel cells while changing reaction temperature (300-500℃), pressure (5-10 bar), and steam/carbon ratio (3:1 to 5:1).

• Solar Energy
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• v.9 no.1
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• pp.36-42
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• 1989

Following the oil crisis in 1979, there have been surge of movements by the government in Korea to conserve petroleum-based energy in every sector of society. One of these movements was the application of passive solar technologies into the construction of school buildings. Various passive designs are developed paying special regard to architectural and climatic factors. This paper is related to the application of the passive solar technology to elementary school buildings. It is proposed to place the hallway on the south side of the building to improve the thermal performance as well as indoor lighting effects. The cases have been compared with those of the existing school buildings where substantial improvements are noted. Finally, standard drawings are prepared in detail to promote the application of this passive solar technology in practical school building.

• Nuclear Engineering and Technology
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• v.45 no.4
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• pp.565-572
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• 2013

The fabrication methods and requirements of the fiber, interphase, and matrix of nuclear grade $SiC_f/SiC$ composites are briefly reviewed. A CVI-processed $SiC_f/SiC$ composite with a PyC or $(PyC-SiC)_n$ interphase utilizing Hi-Nicalon Type S or Tyranno SA3 fiber is currently the best combination in terms of the irradiation performance. We also describe important material issues for the application of SiC composites to LWR fuel cladding. The kinetics of the SiC corrosion under LWR conditions needs to be clarified to confirm the possibility of a burn-up extension and the cost-benefit effect of the SiC composite cladding. In addition, the development of end-plug joining technology and fission products retention capability of the ceramic composite tube would be key challenges for the successful application of SiC composite cladding.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.26 no.1
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• pp.26-31
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• 2014

This study looks into changing building energy use by application of phase change material (PCM). PCM does not need extra energy for operation and is used for reducing building energy use and, CO2 output by displaying semi-permanent effects after installation. It also is able to avoid the maximum electric power time-zone by inducing a time lag phenomenon of cooling and heating loads with high thermal capacity using latent heat. To verify the efficiency of blinds and PCM, tests about the PCM operation mechanism using air conditioning machinery and nocturnal panel cooling were done. In the test results of the case using PCM installation, a $45^{\circ}$ blind angle with machinery air conditioning and nocturnal panel cooling at the same time shows a 22 percent energy saving effect against general space. The test results of each case were compared and analyzed based on the blind and window opening settings. Finally, the energy reduction of existing buildings using PCM application was reviewed based on the final measurement results.

• Nuclear Engineering and Technology
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• v.54 no.12
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• pp.4393-4411
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• 2022

In recent years, beryllium oxide has been widely utilized in multiple compact nuclear reactors as the neutron moderator, the neutron reflector or the matrix material with dispersed nuclear fuels due to its prominent properties. In the past 70 years, beryllium oxide has been studied extensively, but rarely been systematically organized. This article provides a systematic review of the application history, thermal properties, mechanical properties, corrosion behavior and fabrication methods of beryllium oxide. Data from previous literature are extracted and sorted out, and all of these original data are attached as the supplementary material, so that subsequent researchers can utilize this paper as a database for beryllium oxide research in reactor design or simulation analysis, etc. In addition, this review article also attempts to point out the insufficiency of research on beryllium oxide, and the possible key research areas about beryllium oxide in the future.

• Journal of the Korean Solar Energy Society
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• v.28 no.6
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• pp.15-23
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• 2008

The article deals with system technology of a new solar heating system which systematically combines exiting solar collector technology, auxiliary electrical water heating, floor heating system and well insulated construction method and its application of this system to apartment house heating system in the cold region, and also analyzed performance of the new system in terms of technical and economic feasibility. Results shows that energy efficiency approaches up to 50% of the energy consumption of local construction from 1980 to 1981. The implementation of "DQ technology" to floor heating system achieved from 79% to 85% of the energy-saving benefits comparing to other housing units which were supplied by the local district heating plant.

• Journal of the Korean Society of Mineral and Energy Resources Engineers
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• v.56 no.3
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• pp.260-269
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• 2019

The application of 3D printing technology in seismic physical modeling was investigated and the related domestic research was conducted. First, seven types of additive manufacturing methods were evaluated. In this report, to confirm the application of 3D printing technology, related studies in domestic and international journals of geophysics were searched and a comprehensive analysis was conducted according to year and the additive manufacturing type. The analysis showed that studies on 3D printing technology have been dominantly conducted since the 2010s, which corresponds to the time when 3D printers were commercialized. Moreover, 87% of the studies used the material extrusion additive manufacturing method, and the research was conducted in specific universities. This research can be used as basic data for application of 3D printing technology in geophysics.

• New & Renewable Energy
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• v.9 no.2
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• pp.40-50
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• 2013

Government spending on research and development increased continuously is much more important to decision-making methodology for rational investment. Rely on a group of minority experts in the application of a general methodology, a tipping effect occur in specific technology field or difficult balanced procedure and objective control to maintain. This paper presents a qualitative-quantitative methodology to avoid such risks by utilizing Technology-Tree pertaining to energy R&D planning of the government Energy Technology Development program. Especially Energy Technology Development program "energy storage system" is applied to the analysis of Technology-Tree, mapping and analysis of existing government-supported projects during the recent 5 years, is derived essential missing elements of the technology value chain. This study suggests that significant evidence is utilized for improving efficiency of government R&D budget considering the importance of technology, domestic research-based and so forth, could be used to implement the R&D project planning.

• Hwankyungkyoyuk
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• v.10 no.2
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• pp.325-338
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• 1997

Review of the global change in various energy usages and resulting environmental impacts were made in terms of population increase, economic development and energy consumption. Greater use of fossil fuels in past couple of centuries give rise to acid rain and gradual climate changes mainly due to Green House inducing gases emissions from fossil fuel combustion. In view of the forthcoming Kyoto conference in December, various alternative options were assessed. To cope with rapidly developing robust Korean economy, the alternative energy options for the sustainable development in 21st Century would be the wider use of Nuclear Energy in parallel with constrained use of fossil fuel and renewable energy development. However there are many hurdles to overcome. One of the most important element is to improve public acceptability of those alternatives. Since public acceptance depend heavily upon individual perception on specific energy technology applications, the basic energy technologies education from primary up to high school education and the related curriculum organization is important. The suggested improvement in education for Nuclear Energy Application was made on the basis of advanced industrial countries with substantial Nuclear Energy Application programs.