• Journal of Hydrogen and New Energy
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• v.31 no.5
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• pp.453-458
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• 2020

In this study, ethylene-propylene-diene monomer (EPDM) rubbers reinforced with various particle size of carbon black were prepared and tested. We followed recently published CSA/ANSI CHMC2 standard "the test methods for evaluating material compatibility in compressed hydrogen applications-polyemr". Measurement of change in hardness, tensile strength and volume were performed after exposure to maximum operating pressure, 87.5 MPa, for 168 hours (1 week). Once EPDM was exposed to high-pressure hydrogen, the samples experience volume increase and degradation of the physical properties. Also, after the dissolved hydrogen was fully eliminated from the specimens, the hardness and the tensile properties were not recovered. The rubber reinforced with smaller sizes of carbon black particles showed less volume expansion and decrease of physical properties. As a result, smaller particle size of carbon black filler led to more resistance to high-pressure hydrogen.

• Journal of the Korean Wood Science and Technology
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• v.44 no.4
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• pp.477-493
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• 2016

A single process using hot water (0% green liquor) and green liquor (GL) was investigated for pre-pulping extraction on two types of raw material. The GL was applied at different alkali charges of 0-5% on a dry wood weight basis. The extractions were performed at an H-factor 900 at $180^{\circ}C$. The 0% and 3% GL extraction detected acetic acid (AA) at 10.02 and $9.94g/{\ell}$, extracts derived from hardwood, 2.46 and $3.76g/{\ell}$, extracts derived from softwood, respectively. The single liquid-liquid extraction (LLE) was studied using tri-n-alkylphosphine oxide (TAPO). Response surface methodology (RSM) was employed as an efficient approach for predictive model building and optimization of AA recovery conditions. The extraction of AA was evaluated with a three-level factorial design. Three independent variables, pH (0.5-3.5), temperature ($25-65^{\circ}C$), and residence time (24-48 min) were investigated. Applying the RSM models obtained, the optimal conditions selected of extracts derived from hard- and softwood with a 3% GL were approximately pH 1.4, $26.6^{\circ}C$, 43.8 min and approximately pH 0.7, $25.2^{\circ}C$, 24.6 min, respectively. The predicted and experimental values of AA recovery yield were similar whilst sugar retention was 100%.

• Journal of Hydrogen and New Energy
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• v.22 no.6
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• pp.925-933
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• 2011

The traditional feedstock for dimethyl ether (DME) has been natural gas obtained by pipeline from a nearby natural gas or oil field. This report focuses on other feedstock: Coal bed methane (CBM). The resource availability and suitability of CBM for DME manufacturing have been investigated. CBM in a short time has become an important industry, providing an abundant clean-burning fuel and also suggesting as a feedstock for gas industry. The use of CBM will have very little impact on the KOGAS' DME process design and economics up to 50 vol% of $CO_2$ in the CBM source. Many of the CBM sources in Asia are high in $CO_2$, but pose no difficulties for the KOGAS' DME plant. Since tri-reformer requires substantial $CO_2$ in its feed, no $CO_2$ removal from the CBM feed is needed. The $CO_2$ in the CBM means that less $CO_2$ needs to be recycled from the downstream in the process.

• Journal of Hydrogen and New Energy
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• v.27 no.6
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• pp.621-627
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• 2016

Low-priced hydrogen is required in petrochemical industry for producing low-sulfur oil, and upgrading low-grade crude oil since environmental regulations have been reinforced. Steel industry can produce hydrogen from by-product gases such as Blast Furnace Gas (BFG), Coke Oven Gas (COG), and Linze Donawitz Gas (LDG) with water gas shift (WGS) reaction by catalysis. In this study, we optimized conditions for WGS reaction with commercial catalysts by BFG and LDG. In particular, the influence on activity of gas-hourly-space-velocity, and $H_2O/CO$ ratios at different temperatures were investigated. As a result, 99.9%, and 97% CO conversion were showed with BFG, and LDG respectively under $350^{\circ}C$ High Temperature Shift (HTS), $200^{\circ}C$ Low Temperature Shift (LTS), 3.0 of $H_2O/CO$, and $1500h^{-1}$ of GHSV. Furthermore, 99.9% CO conversion lasted for 250 hours with BFG as feed gas.

• Journal of the Korean Society of Safety
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• v.23 no.6
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• pp.57-61
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• 2008

In order to maintain the continual safety management in a company, it needs to evaluate and monitor its implementation of safety management. Because the number of major-accidents is not an effective method of indicating company's safety performance, various efforts to develop more reasonable indicators have been made in world wide. After Korean government has legally required the PSM report, PSM compliance audit has been developed and made by the authorities concerned since 2005. However, this audit consists of complicate procedures difficult to utilize as companies' own audit program and corresponds to only a conformity check that confirms whether the PSM be operated and maintained properly. So a new index by which to measure easily the level of safety performance and self-monitor the implementation of safety management is needed. We have studied a new method that may quantitatively evaluate the performance of safety management by investigating application cases in foreign countries and doing the domestic survey of lots of companies subject to PSM regulation in Korea. This study proposes three of safety performance indices(SPI) together with the several prerequisite preconditions and the timing for application of each index. Although the first draft of SPI needs further legal support, it might help to evaluate every company's safety level. The second draft of SPI is a voluntarily evaluating method based on web-site online program. The last draft of SPI consists of a series of simple questions about 12 elements of PSM. Also each of 3 indices has differences in evaluation methodology and application area and, therefore, they may be used concurrently.

• Journal of the Korea Computer Industry Society
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• v.8 no.4
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• pp.237-244
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• 2007

In this paper we investigate the benefits of a data aggregation to prolong the lifetime of wireless sensor networks. To reduce the overload of messages from source node to sink node, data aggregation technique is generally used at intermediate node in path. The DD-G(Directed Diffusion-Greedy) can diminish the consumption of node energy by establishing energy effective single path from source to destination. In this case, the nodes near sink node have some problems, i) overly concentration of energy consumption, ii) increase of message delay time. To solve these problems, we propose a new data aggregation method which consider distribution of network overload, especially at the nodes close to sink node. The result shows that it can save energy and network delay time.

• Journal of Digital Convergence
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• v.10 no.11
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• pp.127-136
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• 2012

In this research, customized management performance index for small and medium enterprises in solar energy area was developed. To acquire management performance index, first Delphi technique is applied and secondly, AHP(Analytic Hierarchy Process) used to give weight to each main index and then final management performance index was achieved. By developing management performance index, top management could manage their company more efficiently.

• Fashion & Textile Research Journal
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• v.8 no.1
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• pp.134-138
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• 2006

The washing efficiency of two types of washing machine- drum(drum washing) and drum using steam jet system(steam drum washing) was studied. The purpose of this paper is to clarify the performance of new steam drum washing. The relationship between washing temperature and washing efficiency(reflectance(%)) by soil removal, and that between washing temperature and electric energy consumption, Fabric damage evaluated by Danish wear method, Fabric shrinkage(%) during laundering were investigated, and compared with those in drum washing machine. Washing efficiency of steam drum washing according to washing temperature is better than that of drum washing. Electric energy consumption and fabric damage in steam drum washing are lower than those of drum washing. Fabric damage increased as washing temperature increased. Shrinkage of fabrics in steam drum washing and drum washing are about same. Therefore, we assumed that in the case of steam drum washing using steam jet system, washing efficiency remarkably increased, and fabric damage decreased, even with a lot of saving in given electric energy and water used.

• Journal of the Korean Professional Engineers Association
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• v.44 no.6
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• pp.40-44
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• 2011

Nuclear energy in Korea began in 1958, when the Korea's atomic energy act was formulated and the relevant organizations were founded. Since then, notwithstanding the two catastrophe like TMI and Chernobyl accident, Korea made a wise decision to expand the peaceful uses of the nuclear energy as well as to localize the essential nuclear design technology of fuel and nuclear steam supply system. This decision resulted in the success of export of nuclear power plants as well as research reactor in 2010s. The Korea's nuclear policy, which well utilized 'international crisis in nuclear business' as 'opportunity of Korea to get. nuclear technology', is believed nice policy as a role model of nuclear new-comer countries. Based upon the success story of localization of nuclear technology, Korea had an eye for a niche market, which was a basis of development of SMART, Korea-made integral PWR. The operation of a SMART plant can sufficiently provide not only electricity but also fresh water for 100,000 residents. Last two years, Korea's nuclear industry team led by the Korea Atomic Energy Research Institute completed the standard design of SMART and applied to the Korea's regulatory body for standard design approval. Now the Korea's licensing authority is reviewing the design with the relevant documents, and the design team is doing its best to realize its hope to get the approval by the end of this year. From next year, the SMART business including construction and export will be explored by the KEPCO consortium.

• Nuclear Engineering and Technology
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• v.56 no.3
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• pp.966-972
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• 2024

Idaho National Laboratory (INL) announced at COP27 it would reach net zero greenhouse gas (GHG) emissions by 2031. As a Nuclear, Energy and Environment, and National Homeland Security laboratory, the predominant solution to closing the clean energy gap will include nuclear as a safe, clean, reliable and affordable electricity source with the additional benefit of producing heat and hydrogen to fuel INL's large transportation fleet. INL's collaboration first vs. competition is essential to the program's success. The focused actions in INL's Nuclear Roadmap include: Infrastructure, Licensing/Regulatory, Financial, Time to Market, Fuel Cycle and Public Confidence/Communications. The roadmap also includes nuclear technology innovations and creative partnerships with utility providers, regulators, businesses, community members, and Indigenous Peoples to accelerate deployment of advanced reactors. Through development of the Net-Zero Nuclear Roadmap, INL will offer a model to provide safe and secure energy for the nation and the world by: (1) establishing the necessary infrastructure on its 890-square mile site to support demonstration, (2) showing proven pathways through the licensing and regulation process, (3) partnering with utilities to ensure commercial application, and (4) collaborating with industry to site new technologies.