• Korean Chemical Engineering Research
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• v.52 no.4
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• pp.425-429
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• 2014

Until a recent day, degradation of PEMFC MEA(membrane and electrode assembly) has been studied, separated with membrane degradation and electrode degradation, respectively. But membrane and electrode were degraded coincidentally at real PEMFC operation condition. During simultaneous degradation, there was interaction between membrane degradation and electrode degradation. Hydrogen permeability was used often to measure degradation of electrolyte membrane in PEMFC. In case of hydrogen permeability measured by LSV(Linear Sweep Voltammetry) method, the degradation of electrode decrease the value of hydrogen crossover current due to LSV methode's dependence on electrode active area. In this study hydrogen permeability was measured by gas chromatograph(GC) when membrane and electrode degraded at the same time. It was showed that degradation of electrode did not affect the hydrogen permeability measured by GC because of GC methode's independence on electrode active area.

• Korean Chemical Engineering Research
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• v.52 no.2
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• pp.175-181
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• 2014

Microbial fuel cells (MFC) were operated with livestock wastes and PEMFC (Proton Exchange Membrane Fuel Cells) MEA (Membrane and Electrode Assembly). OCV of MFC with mixtures of microbial was higher than that of MFC with single microbial. MFC using pig wastes showed highest OCV (540 mV) among cow waste, chicken waste and duck waste. And the power density of MFC using pig waste was $963mW/m^2$. Contamination of MEA with $Na^{2+}$, $Ca^{2+}$, $K^+$ ion and impurities was the one cause for low performance of MFC during operation.

• Korean Chemical Engineering Research
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• v.54 no.4
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• pp.453-458
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• 2016

Microbial fuel cells (MFC) were operated with pig wastes and PEMFC (Proton Exchange Membrane Fuel Cells) MEA (Membrane and Electrode Assembly). Performance of hydrocarbon membrane was compared with that of perfluoro membrane at MFC condition. Sulfonated-Poly(Arylene Ether Sulfone) was used as hydrocarbon membrane and Gore membrane was used as perfluoro membrane. OCV of sPAES MEA was 50mV higher than that of Gore MEA and power density of sPAES MEA was similar that of Gore MEA. Reinforcement of sPAES membrane stabilized the performance of MEA in MFC. The highest performance was obtained at temperature of $45^{\circ}C$ and with culture solution circulation rate of 50 ml/min. The highest power density was $1,100mW/m^2$ at optimum condition in MFC using pig waste.

• Journal of the Korean Geographical Society
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• v.48 no.5
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• pp.750-767
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• 2013

The purpose of this study is to consider debates the reorganization of administrative districts and to investigate the role of maps in this debate during the early stage of French Revolution. For this, firstly, we examined the argument of reformers who attempted to change the administration system of the Old Regime. We found that physiocrats proposed map use for their attempt to reform this system. Secondly, we considered the debate on the theme of the new division of the kingdom on the basis of speeches or interventions delivered to the National Assembly. Robert de Hesseln's map, itself influenced by the geometric spirit shown by the map of Cassini, played an crucial role in the utopian ideas of revolutionaries who would divide France in administrative units of equal size geometric grid. Thirdly, the deputies decided the number and boundary of department on the basis of Hennequin's map. The final cut which resulted in very tense negotiations with local leaders was irregular polygons modeled on patterns of economic relations, and elements of relief and historical tradition. Fourthly, new administrative divisions are plotted on the map of Cassini and presented to the National Assembly. And it was declared as a new administrative division of France.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.20 no.5
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• pp.103-110
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• 2021

The mounting performance of the GFRP(Glass fiber Reinforced Plastic) beam and the mechanical mounting of the steel bracket was studied to be mounted as a GFRP impact beam on the side door of the passenger car. Moreover, an open-hole tensile test was performed to evaluate breakage tendency based on GFRP stacking conditions. Furthermore, the tightening strength of rivets and bolts was compared using the single lap-shear tension test for the GFRP stacking pattern. Additionally, the GFRP beam and bracket mounting features were designed; moreover, the prototype and bracket were assembled. Additionally, the bracket mounting bending test and the door assembly static bending test were performed to verify the stability of the bracket mounting. In the bracket fastening bending test, no breakage occurred in the connection part between the GFRP beam and the bracket, and it showed 67% (24.4 kN) improved performance compared to steel. In the static bending test of the door assembly, the initial average reaction force increased by 25% compared to the steel, and the performance of all FMVSS-214 regulations was satisfied. The replacement of GFRP impact beams resulted in a 30% weight reduction

• Proceedings of the Korean Biophysical Society Conference
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• 2002.06b
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• pp.28-28
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• 2002

Peptidoglycan is an extensively cross-linked polymer essential for the integrity of the bacterial cell wall. Many antibiotics act by disruption of its biosynthesis and assembly, several are targeted against the cytoplasmic enzymes that synthesize the key intermediate UDP-N-acetylmuramyl pentapeptide. One such drug is fosfomycin, which inactivates the first enzymes in this pathway, UDP-N-acetylglucosamine enopyruvyl transferase (murZ).(omitted)

• Proceedings of the Korean Biophysical Society Conference
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• 1999.06a
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• pp.42-42
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• 1999

Metastability in the native form of proteins has been recognized as a mechanism of biological regulation. The strained native structure of serpins (serine proteinase inhibitors) is a typical example. The native strain of serpins is considered to be crucial to their physiological functions, such as plasma proteinase inhibition, hormone delivery, Alzheimer filament assembly, and extracellular matrix remodeling.(omitted)

• Journal of the Korean Professional Engineers Association
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• v.44 no.6
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• pp.29-34
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• 2011

Korea has been officially classified as a non Annex-I country under the Kyoto Protocol, however, international community is used to considering it as if it were an Annex-I country. Korea has been under great pressure from the international community, especially from the EU and the US, to get included as an Annex-I country or to accept a legally-binding emissions reduction target like other developed nations. Korean Government declared its national target of emissions reduction in 2020 before the Copenhagen meeting, and also pronounced "Low-Carbon Green-Growth" as a new national paradigm to drive the entire nation toward a low carbon society and develop a new growth momentum. The 'green Act', which was passed by the National Assembly in 2009, is a comprehensive and fundamental law providing legal grounds to all of the national policies and measures that are needed to transform the nation into a low-carbon society. Korean government announced to begin Carbon Emissions Trading from 2015, instead of the originally scheduled year of 2013, considering global trends and industrial competitiveness in a flexible manner. The Carbon Emission Trading would reduce carbon emissions by 30 percent from the expected 2020 level, or 4 percent below its emissions in 2005.

• Korean Journal of Animal Reproduction
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• v.24 no.2
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• pp.143-154
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• 2000

Most eggs initiated the fertilization processes but arrested at specific stages. The stages included failure of the oocyte to exit from the meiotic metaphase-II with or without sperm penetration, failure of appropriate sperm aster formation, inability to form proper male and female pronuclei, failure of suitable pronuclear apposition, and failure to form proper number of either male or female pronuclei. Various images of defective microtubule organization and chromatin configuration during IVF and ICSI procedures were observed. We discussed the data with previous research results during normal fertilization in humans and other mammals. In conclusion, various aberrant patterns in microtubule assembly and chromatin configuration, which were assessed in the present study, could be used as criteria to improve assisted reproductive technology in clinics. However, further cellular and molecular characterization is needed to clarify these aberrant patterns of cytoskeletal assembly.

• Korean journal of communication and information
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• v.81
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• pp.189-224
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• 2017

The case of 'Paik Jong-moon's Taped Conversation,' has presented "an important and serious challenge to the freedom of the press and democracy" in South Korea. Nevertheless, this case has not been reported by the mainstream news media. It has also been forgotten without a proper fact-finding or investigation by regulatory agencies, like The Foundation for Broadcast Culture, The Korea Communications Commission, or The National Assembly. This study aims to examine why the above has happened through in-depth interviews of reporters and TV producers, senior journalists, former and incumbent commissioners of the broadcasting regulatory agencies, and experts of the industry, as well as literature research. Here, I present three answers. First, I found two reasons the mainstream press has ignored this incident. 1) It serves for political interests instead of reporting truth. 2) Public broadcasters' watchdog role has been neutralized. Second, regulatory agencies like The Foundation for Broadcast Culture, The Korea Communications Commission and The National Assembly are ruled by political tribalism. The ruling party's members of the National Assembly and these agencies were reluctant to investigate allegations surrounding Paik Jong-moon, such as illegal dismissals, illegal intervention in programming or production, illegal recruitment and illegal business deals. That's because they considered CEO Paik an ally. Using their majority power, they have rejected the request from opposition-affiliated commissioners or from opposition lawmakers to investigate the allegations. Third, there were no alternative forces within the public broadcasters to unveil the truth. In conclusion, the legal and institutional shake-up of corporate governance is urgently needed for public broadcasters and broadcasting regulatory agencies.