• Proceedings of the Korean Fiber Society Conference
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• 1991.06b
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• pp.18-18
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• 1991

• Journal of Life Science
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• v.28 no.12
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• pp.1516-1522
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• 2018

Atherosclerosis is an obstructive vessel disease mainly caused by chronic arterial inflammation to which the proliferation and migration of vascular smooth muscle cells (VSMCs) is the main pathological response. In the present study, the primary responsible inflammatory cytokine and its signaling pathway was investigated. The proliferation and migration of VSMCs was significantly enhanced by the prostaglandin $F_{2{\alpha}}$ ($PGF_{2{\alpha}}$), while neither was affected by tumor necrosis factor ${\alpha}$. Prostacyclin $I_2$ was seen to enhance the proliferation of VSMCs while simultaneously suppressing their migration. Both prostaglandin $D_2$ and prostaglandin $E_2$ significantly enhanced the migration of VSMCs, however, proliferation was not affected by either of them. The proliferation and migration of VSMCs stimulated by $PGF_{2{\alpha}}$ progressed in a dose-dependent manner; the $EC_{50}$ value of both proliferation and migration was $0.1{\mu}M$. VSMCs highly expressed the phospholipase isoform $C-{\beta}3$ ($PLC-{\beta}3$) while others such as $PLC-{\beta}1$, $PLC-{\beta}2$, and $PLC-{\beta}4$ were not expressed. Inhibition of the PLCs by U73122 completely blocked the $PGF_{2{\alpha}}$-induced migration of VSMCs, and, in addition, silencing $PLC-{\beta}3$ significantly diminished the $PGF_{2{\alpha}}$-induced proliferation and migration of VSMCs. Given these results, we suggest that $PGF_{2{\alpha}}$ plays a crucial role in the proliferation and migration of VSMCs, and activation of $PLC-{\beta}3$ could be involved in their $PGF_{2{\alpha}}$-dependent migration.

• Journal of Engineering Education Research
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• v.12 no.2
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• pp.89-95
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• 2009

This thesis investigated way of employment, education course of a training school of Programmable Logic Controller a Field. I inquired into a demand of an engineer and a necessary level of professional education. As a result, I have a purpose in what offer the information that cared for a beginning to work elevation and education training and boat development of a student more than. Faced a human power demand in an education demand and a field rehearsal student demand and analyzed it. The sample extraction used industrial classification, work of scale, Assignment sample extraction way (quota sampling). All data called at a silver phone and the investigated, The data parser analyzed the statistics that used Microsoft Excel.

• Proceedings of the KIEE Conference
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• 1999.07g
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• pp.3067-3069
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• 1999

In this paper, A bit processor for controlling sequence logic was implemented, using a FPGA. This processor consists of program memory interface. I/O interface, parts for instruction fetch and decode, registers, ALU, program counter and etc. This FPGA is able to execute sequence instruction during program fetch cycle, because of divided bus system, program bus and data bus. Also this bit processor has instructions set that 16bit or 32bit fixed width, so instruction decoding time and data memory interface time was reduced. This FPGA was synthesized by pASIC 2 SpDE and Synplify-Lite synthesis tool of Quick Logic company. The final simulation for worst cases was successfully performed under a Verilog HDL simulation environment. And the FPGA programmed for an 84 pin PLCC package. Finally, the benchmark was performed to prove that Our FPGA has better performance than DSP(TMS320C32-40MHz) for the sequence logic control of PLC.

• Proceedings of the KIEE Conference
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• 2004.07d
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• pp.2257-2259
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• 2004

Water Treatment Operation System is applied in most water treatment plants with DCS(Distributed Control System) or PLC(Programmable Logic Controller) system. But it has a lot of problems in viewpoint of cost and expansibilities. Therefore, we rose demand about a system that it was easier, convenient and a few costs. So, It was appeared at a Fieldbus as an alternative about this. It is used in ail industrial fields, but because of the economic reality that we can't removes the existing system, and cannot introduce new technology. Because it is actual to be hard to find an actual implementation reward and way of domestic fieldbus technology, we cannot be acknowledged with reliability in the industrial spot. Therefore, We is going to look into a fieldbus application reward in this paper. That is, We recognize structure and a kind of a fieldbus in a Chapter 2. And we is going to look into difference between a PLC method and fieldbus methods in a Chapter 3. Also, We are going to compare the system that used PLC with the system that used fieldbus (LonWorks). And the objects are JinAn and Wonju where a field bus was applied to.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.17 no.2
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• pp.90-96
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• 2008

A pneumatic system was proposed to evaluate displacement accuracy of the pneumatic actuator without external load and to analyze capability of integration of the proposed valve system. The proposed pneumatic system consisted of a combination of pneumatic valves, two proximity sensors, and a programmable logic controller(PLC). The position controller is based on the PLC controller connected with the proximity sensors. Displacement accuracy of the pneumatic cylinder stroke was tested by varying air pressures of the supply and discharge-side and strokes of the pneumatic cylinder. The displacement accuracy of the pneumatic cylinder stroke increased as the supply and discharge side of air pressure increased at the stroke length of 133mm. Also the displacement accuracy increased as the stroke length increased with a fixed supply and discharge side of air pressure of the pneumatic cylinder as 3.5 and $4.5kg/cm^2$, respectively. The most accurate displacement of the pneumatic cylinder(i.e., standard deviation of 0.01 mm) was obtained at the supply and discharge side of air pressure of 4.0 and $5.0kg/cm^2$, respectively, and strokes of 170 and 190 mm among arbitrarily selected supply and discharge side air pressures and strokes.

• International Journal of Oral Biology
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• v.34 no.4
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• pp.215-222
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• 2009

Medial vestibular nucleus (MVN) neurons are involved in the reflex control of the head and eyes, and in the recovery of vestibular function after the formation of peripheral vestibular lesions. In our present study, whole cell patch clamp recordings were carried out on MVN neurons in brainstem slices from neonatal rats to investigate the actions of a group I metabotropic glutamate receptor (mGluR) agonist upon synaptic transmission and ionic currents. Application of the mGluR I agonist (S)-3,5- dihydroxyphenylglycine (DHPG) increased the frequency of miniature inhibitory postsynaptic currents (mIPSCs) but had no effect upon amplitude distributions. To then identify which of mGluR subtypes is responsible for the actions of DHPG in the MVN, we employed two novel subtype selective antagonists. (S)-(+)-$\alpha$-amino-a-methylbenzeneacetic acid (LY367385) is a potent competitive antagonist that is selective for mGluR1, whereas 2-methyl-6-(phenylethynyl)-pyridine (MPEP) is a potent noncompetitive antagonist of mGluR5. Both LY367385 and MPEP antagonized the DHPG-induced increase of mIPSCs, with the former being more potent. DHPG was also found to induce an inward current, which can be enhanced under depolarized conditions. This DHPG-induced current was reduced by both LY367385 and MPEP. The DHPG-induced inward current was also suppressed by the PLC blocker U-73122, the $IP_3$ receptor antagonist 2-APB, and following the depletion of the intracellular $Ca^{2+}$ pool by thapsigargin. These data suggest that the DHPG-induced inward current may be mainly regulated by the intracellular $Ca^{2+}$ store via the PLC-$IP_3$ pathway. In conclusion, mGluR I, via pre- and postsynaptic actions, may modulate the excitability of the MVN neurons.

• Molecules and Cells
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• v.38 no.7
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• pp.616-623
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• 2015

P2 receptors are membrane-bound receptors for extracellular nucleotides such as ATP and UTP. P2 receptors have been classified as ligand-gated ion channels or P2X receptors and G protein-coupled P2Y receptors. Recently, purinergic signaling has begun to attract attention as a potential therapeutic target for a variety of diseases especially associated with gastroenterology. This study determined the ATP and UTP-induced receptor signaling mechanism in feline esophageal contraction. Contraction of dispersed feline esophageal smooth muscle cells was measured by scanning micrometry. Phosphorylation of $MLC_{20}$ was determined by western blot analysis. ATP and UTP elicited maximum esophageal contraction at 30 s and $10{\mu}M$ concentration. Contraction of dispersed cells treated with $10{\mu}M$ ATP was inhibited by nifedipine. However, contraction induced by $0.1{\mu}M$ ATP, $0.1{\mu}M$ UTP and $10{\mu}M$ UTP was decreased by U73122, chelerythrine, ML-9, PTX and $GDP{\beta}S$. Contraction induced by $0.1{\mu}M$ ATP and UTP was inhibited by $G{\alpha}i_3$ or $G{\alpha}q$ antibodies and by $PLC{\beta}_1$ or $PLC{\beta}_3$ antibodies. Phosphorylated $MLC_{20}$ was increased by ATP and UTP treatment. In conclusion, esophageal contraction induced by ATP and UTP was preferentially mediated by P2Y receptors coupled to $G{\alpha}i_3$ and $G{\alpha}q$ proteins, which activate $PLC{\beta}_1$ and $PLC{\beta}_3$. Subsequently, increased intracellular $Ca^{2+}$ and activated PKC triggered stimulation of MLC kinase and inhibition of MLC phosphatase. Finally, increased $pMLC_{20}$ generated esophageal contraction.

• Nuclear Engineering and Technology
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• v.51 no.7
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• pp.1791-1798
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• 2019

Instrumentation and Control (I&C) systems of nuclear power plants (NPPs) have been continuously digitalized. These systems have a critical role in the operation of nuclear facilities by functioning as the brain of NPPs. In recent years, as cyber security threats to NPP systems have increased, regulatory and policy-related organizations around the world, including the International Atomic Energy Agency (IAEA), Nuclear Regulatory Commission (NRC) and Korea Institute of Nuclear Nonproliferation and Control (KINAC), have emphasized the importance of nuclear cyber security by publishing cyber security guidelines and recommending cyber security requirements for NPP facilities. As described in NRC Regulatory Guide (Reg) 5.71 and KINAC RS015, challenge response authentication should be applied to the critical digital I&C system of NPPs to satisfy the cyber security requirements. There have been no cases in which the most robust response authentication technology like challenge response has been developed and applied to nuclear I&C systems. This paper presents a challenge response authentication mechanism for a Programmable Logic Controller (PLC) system used as a control system in the safety system of the Advanced Power Reactor (APR) 1400 NPP.

• Nuclear Engineering and Technology
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• v.56 no.5
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• pp.1863-1873
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• 2024

In the Korean domestic nuclear industry, to analyze the reliability of instrumentation and control (I&C) systems, the failure rates of the electronic components constituting the I&C systems are predicted based on the MIL-HDBK-217F standard titled 'Reliability Prediction of Electronic Equipment'. Based on these predicted failure rates, the mean time to failure of the I&C systems is calculated to determine the replacement period of the I&C systems. However, this conventional approach to the prediction of electronic component failure rates assumes that factors affecting the failure rates such as ambient temperature and operating voltage are static constants. In this regard, the objective of this study is to propose a prediction method for the remaining useful life (RUL) of electronic components considering mean time to failure calculations reflecting dynamic environments, such as changes in ambient temperature and operating voltage. Results of this study show that the RUL of electronic components can be estimated depending on time-varying temperature and electrical stress, implying that the RUL of electronic components can be predicted under dynamic stress conditions.