• Proceedings of the Korean Magnestics Society Conference
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• 2008.12a
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• pp.287.1-287.1
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• 2008

• Journal of Korean Vacuum Science & Technology
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• v.4 no.1
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• pp.33-37
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• 2000

Properties of electrical discharge in flames and influence of plasma electrons on gas neutrals are investigated by making use of the ionization cross section of air. Frames have three distinctive features. They are hot, emit light and are weakly ionized. We investigate influence of these three characteristics of flames on the electrical breakdown. It is found that the breakdown electric field in flames is inversely proportional to the flame temperature T$\_$g/, thereby easily generating plasmas in flames. A swarm of low-energy electrons in flames would allow a significant population of electronically excited states of flame molecules to be formed. Therefore, the analysis shows that the electronic excitation of flame molecules may also considerably reduce the breakdown field. Plasma electrons generate atomic oxygen by the electron attachment of oxygen molecules in high-pressure flames. These oxygen atoms are the most reactive radicals in flames for material oxidation.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2005.11b
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• pp.114-117
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• 2005

In the reactive concentric resonator, perforated inner tubes are widely used for various purposes related to noise reduction, flow guiding, and structural aspects. Perforation distribution patterns influence both the acoustic performance and mechanical performance. In this study, the influence of distribution patterns on acoustic performance are explained by adopting the concept of extended inlet/outlet length. Predicted transmission with varying extended inlet/outlet length is compared with prediction by varying distribution patterns. The transmission loss difference due to perforation distribution patterns can be explained by changing the extended inlet/outlet length of the uniformly perforated resonator.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09b
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• pp.727-728
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• 2006

The present work studies the influence of high-energy milling (HEM) and sintering cycle of Ti and Al powders on the obtainment of TiAl. This study shows that HEM modifies the diffusion processes during the sintering stage. The samples were obtained by cold uniaxial and isostatic pressing, pre-sintered at different temperatures, and heated up to the sintering temperature. This study also shows the effect of powder additions processed by HEM on the sintering behavior of elemental Ti and Al powders.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• v.11 no.3
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• pp.7-20
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• 2007

We examined the steady state solution for a strongly exothermic mixtures in some class A geometries subjected to different boundary conditions under Arrhenius, Bimolecular and Sensitised reactions. The solution of the governing nonlinear reaction diffusion equation was obtained using the variational method formulation executed in Mathematica package. The paper elucidates the influence of geometry, boundary conditions and types of reaction on the thermal ignition of the reactive mixture. Apart from validating known results in literature, the solution gave further insight into the influence of material properties and conditions on the occurrence of thermal ignition.

• Journal of the Korean Society of Clothing and Textiles
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• v.38 no.4
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• pp.455-466
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• 2014

This study examines the effectiveness of CSR through the expectancy disconfirmation theory. The change of CSR belief after a corporate social irresponsibility (CSIR) crisis was investigated in terms of activity timing (proactive activities before CSIR crisis/reactive activities after CSIR crisis). Study 1 explores the influence of CSR belief perceptions formed through usual CSR activities on CSR belief decline after a CSIR crisis and the moderating effect of CSR activity types. Higher CSR belief perceptions are formed through usual CSR activities that result in a large CSR belief decline. The moderating effect of CSR activity types on CSR belief decline is found. Volunteer activity has the strongest depending effect on CSIR crisis. Study 2 explores the influence of CSR belief perceptions formed through CSIR crisis on a CSR belief incline after CSR activities and the moderating effect of CSR activity types. The lower CSR belief perception after CSIR crisis results in a high CSR belief incline after CSR activities. The moderating effect of CSR activity types on CSR belief incline is found. Cause-related marketing has the strongest overcoming effect on a CSIR crisis.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.66 no.4
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• pp.151-157
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• 2017

In this paper, it is the result of analysis of the stability by power system analysis about the influence on the power system when the southwest - offshore wind power demonstration complex is constructed to 60MW and it is linked with the onshore power system. Considering the position of the wind turbine actually installed and the length of the cooperating line, we modeled the wind generators, offshore substation and the turbine step-up transformer. Changes of voltage when internal and external faults occurred is analyzed and the reactive power demand according to the amount of electricity generation is derived. And also phase angle stability and frequency is observed through a transient analysis. This paper clarify that there is no problem in the system when only offshore wind power is linked with the grid and try to present the reactive power amount necessary for maintaining the voltage of the point of cooperation appropriately.

• Journal of Microbiology and Biotechnology
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• v.23 no.10
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• pp.1386-1394
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• 2013

In our previous study, the 25-mer antimicrobial peptide pleurocidin (Ple) had been thought to induce apoptosis in Candida albicans. This study demonstrated that reactive oxygen species (ROS) production was a major cause of Ple-induced apoptosis. Four truncated analogs were synthesized to understand the functional roles in the N- and C-terminal regions of Ple on the apoptosis. Ple, Ple (4-25), Ple (1-22), and Ple (1-19) produced ROS, including hydroxyl radicals, on the order of [Ple > Ple (1-22) > Ple (4-25) > Ple (1-19)], whereas Ple (7-25) did not induce any ROS production. The results suggested that the N-terminal deletion affected the ROS-inducing activities much more than that of the C-terminal deletion, and net hydrophobicity [Ple > Ple (1-22) > Ple (4-25) > Ple (1-19) > Ple (7-25)] was related to ROS generation rather than other primary factors like net charge. Hence, we focused on the N-terminal-truncated peptides, Ple (4-25) and Ple (7-25), and examined other apoptotic features, including mitochondrial membrane depolarization, caspase activation, phosphatidylserine externalization, and DNA and nuclear fragmentation. The results also confirmed the disappearance of apoptotic activity of Ple (7-25) by the truncation of the N-terminal region (1-6) and the specific activity patterns between Ple and analogs. In conclusion, the N-terminal region of Ple played an important role in apoptosis.

• Proceedings of the KWS Conference
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• 2002.10a
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• pp.545-550
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• 2002

In order to ensure the signal could be transported cocrrectly, the microwave devices made of Aluminmn alloys must be assembled and brazed flaw-freely. In this paper, a new approach of using contact reactive brazing (CRB) process to realize the compact brazing of Aluminum alloys was put forward. The reason for this is that CRB, which realizes bonding depending on the liquid alloy produced by metallurgy reaction between the materials to be joined, overcomes the limitation of traditional brazing that the macroscopically disorganized filling flow of liquid filler metal would result in defects in brazed seam. Joint ofLF21 (AA3003) with the compactness of over 95% was brazed by the method of CRB using Si powder as an interlayer. At last, the influence of the physical parameter related to the Si powder interlayer on the compactness of the joints was investigated in detail.

• Korean Chemical Engineering Research
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• v.44 no.5
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• pp.483-488
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• 2006

Etching process of PMMA (Polymethyl Methacrylate) on glass surface was investigated by dry etching technique using remote plasma. To determine the etching characteristics, the remote plasma etching was conducted for various process parameters such as plasma power, reaction gas and distance from plasma generation. As the distance from the plasma generation was increased, the etch rate of PMMA was linearly decreased by radical density in plasma. PMMA has removed by reactive radicals in the plasma. The etch rate increased with plasma power because of more reactive radicals. The etch rate and surface roughness of PMMA increased with $O_2$ concentration in the etchant.