• Proceedings of the Plant Resources Society of Korea Conference
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• 한국자원식물학회 2000년도 춘계임시총회 및 학술발표대회
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• pp.23-25
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• 2000

• Proceedings of the Korea Water Resources Association Conference
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• 한국수자원학회 2005년도 학술발표회(1)
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• pp.530-531
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• 2005

• Proceedings of the Korean Institute of Resources Recycling Conference
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• 한국자원리싸이클링학회 2005년도 춘계임시총회 및 제25회 학술발표대회
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• pp.109-112
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• 2005

The electrical pulse separation of concrete samples for the recycling purpose has been investigated by the electrical disintegration method using the discharged high voltageimpulse. First, when the consumed energy increased in electrical crushing, fracture section area increased clearly. This result suggests that crushing energy was consumed efficiently. Secondly, when conventional crushing after electrical disintegration is compared with only conventional crushing, gravels are more stable after electrical crushing. Thus, electrical crushing makes it easy to recover gravels from wasted concrete. In the next year, more efficient recovery of gravel for wasted concrete by electrical disintegration will be investigated. Thus, actual wasted concrete crushing by electrical separation and combination of conventional crushing will be carried out.

• Asian-Australasian Journal of Animal Sciences
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• 제24권9호
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• pp.1256-1267
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• 2011

Two experiments were conducted to determine the effects of dietary lysine and energy level on performance and apparent total tract digestibility (ATTD) of nutrients in weanling pigs. In Exp. 1, a total of 288 weaned pigs (initial BW $5.77{\pm}0.85\;kg$) were randomly allotted to 4 treatments (4 replicates per treatment with 18 pigs in each replicate). Experimental diets were fed in the 3 phases: phase I (d 0 to 7), phase II (d 8 to 14) and phase III (d 15 to 28). Isocalorific diets (3,450 kcal/kg) with incremental lysine levels (Phase I: 1.51, 1.61, 1.71 and 1.81; Phase II: 1.35, 1.46, 1.56 and 1.66; Phase III: 1.18, 1.28, 1.39 and 1.49% lysine respectively for T1, T2, T3 and T4) were used as treatments. An increase in the dietary lysine levels linearly improved (p<0.05) the ADG and G:F during phases I, II and III as well as overall study period. The ATTD of DM (d 7 and 28) and CP (d 7, 14 and 28) were linearly improved (p<0.05) with increasing dietary lysine levels. ATTD of ash, Ca and P were not affected by dietary lysine level. In Exp. 2, 64 weanling pigs (initial BW $4.79{\pm}0.79\;kg$) were randomly allotted to 4 treatments (4 replicates per treatment with 4 pigs in each replicate) in a $2{\times}2$ factorial arrangement on the basis of BW. Effects of two levels of energy (high, 3,450 or low, 3,350 kcal/kg) and lysine (high or low; 1.70 or 1.50, 1.55 or 1.35 and 1.40 or 1.20% in phase I, II and III diets, respectively) on performance and ATTD of nutrients were investigated. High energy and lysine diets improved ADG (p<0.05) in pigs during phase I, II and III and overall period (p<0.001), while G:F increased (p<0.05) during phase I and overall period. Pigs fed high lysine diets consumed more (p<0.05) feed during phase III and overall period. Additionally, pigs fed high energy diets had greater (p<0.05) ATTD of GE (d 7 and 14), CP (d 7 and 28) and DM (d 28); whereas, pigs fed high lysine diets had greater (p<0.05) ATTD of GE and CP during d 7, 14 and 28. ATTD of ash, Ca and P remained unaffected (p>0.05) by dietary energy and lysine level. However, there was no energy${\times}$lysine interaction for any of the measured variables. Results obtained in present study suggested that high energy and lysine level improve the growth performance and ATTD of nutrients in weanling pigs.

• Journal of Korean Society of Rural Planning
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• 제14권2호
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• pp.25-32
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• 2008

Wind energy, which is one of renewable energy, would be useful resources that can be applied to making energy recycling villages without using fossil fuels. This study analyzed energy potential on wind power considering weather condition in three rural villages and compared with energy consumption surveyed. A wind turbine system in the 5kW class can generate 26.1%, 73.9% and 39.5% of the yearly mean consumption of electric power per house in Makhyun, Boojang and Soso respectively. A 750kW wind turbine system can generate 1.7%, 30.3% and 22.1% of the total amount of electric power consumption in three study villages respectively. Wind power energy density was too low in Makhyun and Soso, so it is determined that the application of wind turbine system is almost impossible. Wind energy potential was generally low in Boojang either, but it is evaluated that there is a little possibility of wind power generation relatively. For practical application of renewable energy to rural green-village planning, assessment of energy potential for the local area should be preceded.

• KEPCO Journal on Electric Power and Energy
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• 제4권1호
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• pp.1-7
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• 2018

Objective signs are everywhere that the stationary energy storage market is growing up quickly. The use of distributed resources such as solar photovoltaics and electric vehicles are expanding at a rapid pace, creating technical challenges for the distribution system that will require energy storage and a new generation of software to address. This paper is intended for distribution utility managers and executives and makes the following points: ${\bullet}$ Utility-integrated (as opposed to merely grid-connected) energy storage projects represent a distinct, new wave of industry growth that is just getting underway and is required to manage distributed energy resources moving forward. ${\bullet}$ Utilities and the energy storage industry have important roles to lower risk in adopting this technology - thereby enabling this wave of growth. ${\circ}$ The industry must focus on engineering energy storage for adoption at scale - including the creation and support of software open standards -both to drive down costs and to limit technology and supplier risk for utilities. ${\circ}$ Utilities need to take a program-based, rather than a project- based, approach to this resource to best balance cost and risk as they procure and implement energy storage. By working together to drive down costs and manage risk, utilities and their suppliers can lay the energy storage foundation for a new, more digital distributed electricity system.

• Resources Recycling
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• 제8권3호
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• pp.9-17
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• 1999

The study investrgated the properti es of lh$\xi$ dust~ from felToalloy manufacture, The chemical composition, composItron material, particle size and shapes of the bulk dust, sized dust and magnetically separated dust were llivestigated. As the result, we s suppose that the dust from HLgh Carbon Fenomauganesc Manufacturing Process is not sufficient as soource material of Mn because of the low Mn conteut (13.5%) aud complicated composition material The dust from Bag Filter of AOD Process is m mainly made up of $0.2~2\mu\textrm{m}$ $Mn_3O_4$ (Hausmatmite) particle in spherical shape and the Mn content is 63.1%. The dust from Cooler of AOD Process is mainly made up of coarse $Ca(OH)_2$ Mn, $Fe_yO_2$ $SiO_2$ and fine $Mn_3O_1$.

• Geophysics and Geophysical Exploration
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• 제22권3호
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• pp.132-148
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• 2019

Recently, safety and environmental concerns have become major social issues. Especially, a special underground-safety law has been made and enacted to prevent ground subsidence around construction sites. For environmental problems, several researches have started or will start on characterization of contaminated sites, in-situ environmental remediation in subsurface, and monitoring of remediation results. As a part of the researches, geophysical surveys, which have been mainly applied to explore mineral resources, geological features or ground, are used to characterize not only contaminated areas but also fluid flow paths in subsurface environments. As a basic study for the application of geophysical surveys to detect contamination in subsurface, this paper analyzes previous researches to understand changes in geophysical properties of contaminated zones by various contaminants such as leachate, heavy metals, and non-adequate phase liquid (NAPL). Furthermore, this paper briefly introduces how geophysical surveys like direct-current electrical resistivity, induced polarization and ground penetration radar surveys can be applied to detect each contamination, before analyzing case studies of the applications in contaminated areas by NAPL, leachate, heavy metal or nitrogen oxides.

• Geophysics and Geophysical Exploration
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• 제26권4호
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• pp.229-237
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• 2023

The use of artificial sources such as explosives and mechanical vibrations for seismic exploration in urban areas poses challenges, as the vibrations and noise generated can lead to complaints. As an alternative to artificial sources, the surface waves generated by traffic noise can be used to investigate the subsurface properties of urban areas. However, traffic noise takes the form of plane waves moving continuously at a constant speed. To apply existing surface wave processing/inversion techniques to traffic noise, the recorded data need to be transformed into a virtual shot gather format using seismic interferometry. In this study, various seismic interferometry methods were applied to traffic noise data, and the optimal method was derived by comparing the results in the Radon and F-K domains. Additionally, the data acquired using various receiver arrays were processed using seismic interferometry, and the results were compared and analyzed to determine the most optimal receiver array direction for exploration.

• New & Renewable Energy
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• 제19권4호
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• pp.27-34
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• 2023

In this study, microalgal oil was extracted from Nannochloropsis oceanica cultured in an open raceway pond and converted into biodiesel using a solid acid catalyst. Microalgal oil was extracted from two types of microalgae with and without nitrogen starvation using the KOH-solvent extraction method and the fatty acid content and oil extraction yield from each microalgae were compared. The fatty acid content of N. oceanica was 184.8 mg/g cell under basic conditions, and the oil content increased to 340.1 mg/g under nitrogen starvation conditions. Oil extraction yields were 90.8 and 95.4% in the first extraction, and increased to 97.5 and 98.8% after the second extraction. Microalgal oil extracted by KOH-solvent extraction was yellow in color and had reduced viscosity due to chlorophyll removal. In biodiesel conversion using the catalyst SO₄^2-/HZSM-5, solvent-extracted oil showed a FAME content of 4.8%, while KOH-solvent-extracted oil showed a FAME content of 90.4%. Solid acid catalyst application has been made easier by removal of chlorophyll from microalgal oil. The FAME content increased to 96.6% upon distillation, and the oxidation stability increased to 11.07 h with addition of rapeseed biodiesel and 1,000 ppm butylated hydroxyanisole.