• Journal of Science Education
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• v.40 no.1
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• pp.72-89
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• 2016

The purpose of this study is to investigate current trends of research in STEAM education through the analysis of published articles in Korea on STEAM education between 2011~2014. By looking into the research trend, this study check out research's achievements for four years and suggest guiding light to determine the direction of the research of STEAM education. The number of papers of STEAM education had continuously increased from 2011 to 2014 but the increase in research tended to stall by 2014. In 2014 the research for kindergartens started to increase and research for slow learning students and special students was done. With regard to the number of studies published relating to the curriculum, many studies centered in the study of the actual and science curriculum which took a large portion since the adoption. In the kindergarten and university level, the study based on art showed the highest while in elementary, middle and high school level, the actual and science curriculum took a major portion in its studies. The general academic associations continue to expand their research area with regard to STEAM education while the academic related associations show a 16% decline in its number of studies published when comparing 2014 to 2013. A higher proportion of qualitative research methods such as case studies are needed to be addressed in the future while more research should be done on education policies for the establishment of a system to share the program that contains the distribution of the education programs and its utilization. In addition, a long-term research should be conducted to verify the effectiveness of the education of teachers for teaching candidates and school teachers.

• Applied Biological Chemistry
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• v.37 no.1
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• pp.30-36
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• 1994

The essential oil of Schizandrae Fructus was extracted by simultanous distillation-extraction and steam distillation and analyzed by GC and GC-MS. The oil content of Schizandrae Frutus was 0.64% when extracted by steam distillation and 0.88% in case of simultanous distillation extraction and sensory analysis of the oil indicated woody, camphorous, spicy and sour characteristic notes. The experimental results confirmed the presence 47 volatile components, the major components were ${\gamma}-terpinene$, p-cymene, ${\alpha}-ylangne$ and ${\beta}-elemene$. The oil was fractioned into ten fractions and 4 fraction of them have a good aroma character. The application of the oil showed the utilization possibility as flavoring materials for Korea tea.

• Journal of Mechanical Science and Technology
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• v.19 no.11
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• pp.2007-2015
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• 2005

A large-scale analysis to evaluate complex material and structural behaviors is one of interesting topic in diverse engineering and scientific fields. Also, the utilization of massively parallel processors has been a recent trend of high performance computing. The objective of this paper is to introduce a parallel process system which consists of general purpose finite element analysis solver as well as parallelized PC cluster. The later was constructed using eight processing elements and the former was developed adopting both hierarchical domain decomposition method and balancing domain decomposition method. Then, to verify the efficiency of the established system, it was applied for structural analysis of steam generator in nuclear power plant. Since the prototypal evaluation results agreed well to the corresponding reference solutions it is believed that, after reinforcement of PC cluster by increasing number of processing elements, the promising parallel process system can be utilized as a useful tool for advanced structural integrity evaluation.

• Proceedings of the SAREK Conference
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• 2009.06a
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• pp.39-44
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• 2009

Geothermal energy is the heat contained in the earth and its internal fluids. Geothermal energy is stored as sensible or latent heat. Supplied by both internal and external sources, it represents a vast supply which is only started to be tapped for generation of electric power. In general, this is natural dry or wet medium to high enthalpy steam at temperatures above $150^{\circ}C$. For some time, binary systems employing substances with a lower boiling point than water in a secondary circuit have been used to generate vapor for driving turbines at a lower temperature level. The utilization of binary plants and the possibility of production from enhanced geothermal systems can expand its availability on a worldwide basis. The geothermal electricity installed capacity is approaching the 10,000GW threshold. Geothermal energy is not present everywhere, but its baseload capability is a very important factor for its success.

• Journal of the Korea Institute of Building Construction
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• v.5 no.2 s.16
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• pp.89-95
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• 2005

Various tests are performed with the recycled concrete including compressive strength, flexural strength, splitting tensile strength, bonding strength and chloride ion penetration test. The basic data obtained from the presented test could be accumulated for the purpose of utilization in concrete structure. Most of the strength tests show that strength decrease a little extent with increasing substitution ratio of recycled coarse aggregate except splitting tensile test for the concrete with $100\%$ recycled fine aggregate. But in case of the $50\%$ substitution of recycled coarse aggregate, compressive strength, flexural strength and bonding strength are almost equal to the normal concrete. Chloride ion penetration test shows that the penetration amounts of chloride ion becomes more in proportion to the substitution ratio of recycled aggregate. But most of the results show that the permeability of recycled concrete is proper to use. The results of present study nay imply that the use of recycled aggregate for steam curing concrete is possible but the substitution ratio of recycled aggregate should be determined through further studies.

• Journal of Hydrogen and New Energy
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• v.26 no.2
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• pp.156-163
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• 2015

The fuel cells have been investigated in the applications of marine as the high efficient and eco-friendly power generating systems. In this study, modeling of IR Type molten carbonate fuel cell (Internal Reforming Type molten carbonate fuel cell) has been developed to analyze the feasibility of thermal energy utilization. The model is developed under Aspen plus and used for the study of system performances over regarding fuel types. The simulation results show that the efficiency of MCFC system based on NG fuel is the highest. Also, it is also verified that the steam reforming is suitable as pre-reforming for diesel fuel.

• Food Science and Preservation
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• v.4 no.1
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• pp.61-68
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• 1997

To enhance the utilization of garlic shoots as food material, the nutritional and volatile flavor com pounds were investigated for garlic shoots, both cold and warm region type garlic shoots. Proximate composition of cold and warm region type was as follows, respectively; crude protein 2%, crude lipid 0.4%, crude ash 1.1% and 1.5%, crude fiber 1.3% and 1.5%. The major fatty acids of 2 varieties of garlic shoots were linoleic, palmitic and linolenic acid, and their desaturation ratio of them was comparatively high, showing 73.7 and 66.8%, respectively. Free sugars were composed of glucose, sucrose, fructose, arabinose and sorbitol. In the total amino acid analysis, the major amino acids were glutamic acid and aspartic acid. The volatile flavor compounds of fresh garlic shoots extracted by hexane and Likens-Nikerson steam distillation apparatus were identified to be methyl-2-propenyl disulfide, diallyl disufide, propenyl propyl disulfide, di-2-propyl-trisulfide, 2-vinyl-1,3-dithiane, and 2-vinyl-4H-1,3-dithiin. Hexane was more effective than steam distillation for extraction of volatile components of garlic shoots.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.35 no.6
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• pp.641-648
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• 2011

Off-gases emitted from the anode of a molten carbonate fuel cell (MCFC) at high temperatures for power generation are used as fuel in catalytic combustion. The heat generated in the catalytic combustor is utilized as the heat for the endothermic reaction required for steam reforming. Among the various operational conditions of the integrated reactor, we varied the inlet gas compositions of the catalytic combustor according to fuel utilization in the MCFC and the ratio of steam to carbon in the reformer. Subsequently, the thermal behaviors and reaction characteristics of the integrated reactor were investigated experimentally. The fundamental data from this experimental study will be useful for the design and fabrication of a more practical integrated reactor in the future.

• Journal of Hydrogen and New Energy
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• v.30 no.4
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• pp.303-311
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• 2019

Reversible solid oxide fuel cell (RSOFC) has become a prospective device for energy storage and hydrogen production. Many studies have been conducted around the world focusing on system efficiency improvement and realization. The system should have not only high efficiency but also a certain level of simplicity for stable operation. External waste steam utilization was proved to remarkably increase the efficiency at solid oxide electrolysis system. In this study, RSOFC system coupled with waste steam was proposed and optimized in term of simplicity and efficiency. Ejector for fuel recirculation is selected due to its simple design and high stability. Three system configurations using ejector for fuel recirculation were investigated for performance of design condition. In parametric study, the system efficiencies at different current density were analyzed. The system configurations were simulated using validated lumped model in EBSILON(R) program. The system components, balance of plants, were designed to work in both electrolysis and fuel cell modes, and their off-design characteristics were taken into account. The base case calculation shows that, the system with suction pump results in slightly lower efficiency but stack can be operated more stable with same inlet pressure of fuel and air electrode.

• Korean Journal of Organic Agriculture
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• v.10 no.1
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• pp.35-47
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• 2002

In swine production, efficiency of utilization of nutrients is imperative. By embracing advances in processing techniques(i.e., fine grinding, pelleting, steam flaking, roasting, extrusion and expanding) nutrient utilization of feeds turfs have greatly improved. Grinding is by far the most commonly used process with reduction of particle size, Expander, like extruders, are high-temperature and pressure-short-term processor. The purpose of using an expander is to improve pellet quality. Also, expanding of dietary ingredients indicates improvements in growth performance and nutrient digestibility. Because feed cost are easily the greatest economic input into swine production, maximizing nutrient utilization is an area that will continue to receive much attention. Therefore, much attention will continue to be placed on feed processing techniques that will give consistent improvements in animal performance and nutrient digestibility.