• Title/Summary/Keyword: MCB

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Solubilization Isotherms of Chlorobenzene in ionic Surfactant Solutions

  • Baek, Ki-Tae;Yang, Ji-Won
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 2003.04a
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    • pp.201-204
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    • 2003
  • Solubilization isotherms of 1-chlorobenzene (MCB) and 1, 2-dichlorobenzene (DCB) were investigated in ionic surfactant solutions such as sodium dodecyl sulfate (SDS), cetylpyridinium chloride (CPC), and dedecyltrimethylammonium chloride (DMAC). The solubilization extent of DCB was much higher than that of MCB because of the main driving force of solubilization Is hydrophobic interactions between chlorobenzenes and hydrophobic interior of ionic micelles and DCB is more hydrophobic than MCB. CPC showed highest solubilization capacity because of longest hydrophobic tails. Simultaneous solubilization of MCB and DCB decreased slightly the extent solubilization of both MCB and DCB because the solubilization locus in the micelles is same.

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Apolar growth of Neurospora crassa leads to increased secretion of extracellular proteins

  • Lee, In-Hyung;Rodney G. Walline;Michael Plamann
    • Proceedings of the Korean Society for Applied Microbiology Conference
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    • 2000.04a
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    • pp.78-89
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    • 2000
  • Protein secretion in filamentous fungi has been shown to be restricted to actively growing hyphal tips. To determine whether an increase in the amount of growing surface area of a fungus can lead to an increase in the amount of protein secretion, we examined secretion in a temperature-sensitive Neurospora crassa mcb mutant that shows a loss of growth polarity when incubated at restrictive-temperature. Incubation of the mcb mutant at restrictive-temperature results in a three- to five-fold increase in the level of extracellular protein and a 20- fold increase in carboxymethyl cellulase activity relative to a wild-type strain. A mutation in the cr-l gene has been shown previously to suppress the apolar growth phenotype of the mcb mutant, and we find that the level of extracellular protein produced by a mcb; cr-l double mutant was reduced to that of the wild-type control. Immunolocalization of a secreted endoglucanase revealed that proteins are secreted mainly at hyphal tips in hyphae exhibiting polar growth and over the entire surface area of bulbous regions of hyphae that are produced following a shift of the mcb mutant to restrictive-temperature. These results support the hypothesis that secretion of extracellular protein by a filamentous fungus can be significantly increased by mutations that alter growth polarity.

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Seismic Qualification of the Main Control Board for Nuclear Power Plant (원자력발전소용 주 제어반의 내진 검증)

  • 변훈석;이준근
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.12 no.11
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    • pp.856-863
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    • 2002
  • Seismic qualification of the main control board(MCB) for the nuclear power plant Ulchin 5 and 6 has been performed with the guideline of ASME Section III and IEEE 344 code. As the size and weight of the MCB are too large and heavy to excite using the excitation table, finite element analysis is used in order to investigate the dynamic behaviors and structural integrity of the MCB. As the fundamental frequencies of the equipment are found to be less than 33 Hz, which is the upper frequency limit for the dynamic analysis, response spectrum analysis using ANSYS is performed in order to combine the modal stresses within the frequency limit. In order to confirm the electrical stability of the major components of the MCB. modal analysis theory has been adopted to derive the required response spectra at the component locations. As the all combined stresses obtained from the above procedures are less than the allowable stresses and no mechanical or electrical failures are found from the seismic testing, the authors can confirm the safety of the nuclear equipment MCB under the given seismic loading conditions.

Study of MCB Operation of Urban train in AC/DC Dead-section (도시철도차량 교직 사구간 MCB 투입 현상 분석)

  • Baik, Kwang-Sun;Kim, Myung-Young;Kim, Jin-Whan
    • Proceedings of the KIEE Conference
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    • 2003.07b
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    • pp.1279-1281
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    • 2003
  • 도시철도차량의 AC/DC 절연구간 통과 방법에 대한 사례를 조사하고 과천선 전동차의 절연구간 구간 통과시 관련 장치의 동작시간을 분석하며 MCB(Main Curcuit Breaker)가 동작할 수 있도록 할 수 있는 다양한 원인에 대한 검토와 측정 결과를 통하여 정확한 원인을 분석한다.

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Study on the Controlled Gel Formation and Photochromic Properties of a New Cholesterol-bridge-naphthopyran Dyad

  • Sun, Lin;Wang, Guang;Liu, Longbo;Wang, Ai Xia
    • Bulletin of the Korean Chemical Society
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    • v.35 no.5
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    • pp.1343-1348
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    • 2014
  • A cholesterol-bridge-naphthopyran dyad (NP-MCB) was designed and synthesized. NP-MCB can readily self-assemble into gels under ultrasound-radiation in several organic solvents and the formed gels easily transfer to solution by heat. This reversible process can be repeated many times. Scanning Electron Microscopy results showed that the morphologies of all formed xerogels in different solvents have fibrillar microstructure. The gels formation was due to energy and pressure afforded by the ultrasonic process, resulting in formation of molecular hydrogen bonding and molecular aggregation. NP-MCB displayed the normal photochromism both in solution and gel states. The kinetic results confirm that the colored merocyanine in gels show a slower fading speed than that in solution due to the compact aggregation of NP-MCB molecules in gels. The xerogel film formed in polar gelling solvent had large surface wettability than that in nonpolar gelling solvent.

Development of Multi-Sensor Convergence Monitoring and Diagnosis Device based on Edge AI for the Modular Main Circuit Breaker of Korean High-Speed Rolling Stock

  • Byeong Ju, Yun;Jhong Il, Kim;Jae Young, Yoon;Jeong Jin, Kang;You Sik, Hong
    • International Journal of Advanced Culture Technology
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    • v.10 no.4
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    • pp.569-575
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    • 2022
  • This is a research thesis on the development of a monitoring and diagnosis device that prevents the risk of an accident through monitoring and diagnosis of a modular Main Circuit Breaker (MCB) using Vacuum Interrupter (VI) for Korean high-speed rolling stock. In this paper, a comprehensive MCB monitoring and diagnosis was performed by converging vacuum level diagnosis of interrupter, operating coil monitoring of MCB and environmental temperature/humidity monitoring of modular box. In addition, to develop an algorithm that is expected to have a similar data processing before the actual field test of the MCB monitoring and diagnosis device in 2023, the cluster analysis and factor analysis were performed using the WEKA data mining technique on the big data of Korean railroad transformer, which was previously researched by Tae Hee Evolution with KORAIL.

Research for Mobile Cloud Broker (모바일 클라우드 브로커 연구)

  • Kim, Heejae;Youn, Chan-Hyun
    • Proceedings of the Korea Information Processing Society Conference
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    • 2012.04a
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    • pp.250-252
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    • 2012
  • 모바일 클라우드란 컴퓨팅을 모바일 기기의 영역 까지 확장시킨 것으로 모바일 기기의 특수성을 고려하여 클라우드 서비스를 제공하는 서비스를 말한다. 본 연구에서 제안하는 모바일 클라우드 브로커(Mobile Cloud Broker, MCB)는 클라우드 서비스를 모바일 환경에서 이용할 수 있도록 여러가지 기능들을 제공해준다. 따라서 본 연구에서는 MCB가 지녀야 하는 요구사항과 구조를 다룬다.

A Development of Intelligent Controller for Phase Control in Main Circuit Breaker (주회로차단기 투입전원 위상제어를 위한 지능형 제어기 개발)

  • Oh, Yong-Kuk;Kim, Jae-Won;Ryu, Joon-Hyoung
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.18 no.11
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    • pp.755-761
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    • 2017
  • In railways powered by AC power, the main circuit breaker (MCB) is used for supplying the electric power to the catenary of the vehicle. Generally, the main circuit breaker is located between the pantograph and the main transformer, and the phase of the power applied to the vehicle changes according to the operation timing of the main circuit breaker. The operation of the main circuit breaker should be actively controlled according to the phase of the power source, since the phase of the power causes unintended transient states in the vehicle's electrical system in the form of an inrush current and surge voltage. However, the MCB has a delay time when it operates which is not constant. Therefore, an intelligent controller is needed to predict the operation delay time and control the opening and closing of the MCB.

Habitability evaluation considering various input parameters for main control benchboard fire in the main control room

  • Byeongjun Kim ;Jaiho Lee ;Seyoung Kim;Weon Gyu Shin
    • Nuclear Engineering and Technology
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    • v.54 no.11
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    • pp.4195-4208
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    • 2022
  • In this study, operator habitability was numerically evaluated in the event of a fire at the main control bench board (MCB) in a reference main control room (MCR). It was investigated if evacuation variables including hot gas layer temperature (HGLT), heat flux (HF), and optical density (OD) at 1.8 m from the MCR floor exceed the reference evacuation criteria provided in NUREG/CR-6850. For a fire model validation, the simulation results of the reference MCR were compared with existing experimental results on the same reference MCR. In the simulation, various input parameters were applied to the MCB panel fire scenario: MCR height, peak heat release rate (HRR) of a panel, number of panels where fire propagation occurs, fire propagation time, door open/close conditions, and mechanical ventilation operation. A specialized-average HRR (SAHRR) concept was newly devised to comprehensively investigate how the various input parameters affect the operator's habitability. Peak values of the evacuation variables normalized by evacuation criteria of NUREG/CR-6850 were well-correlated as the power function of the SAHRR for the various input parameters. In addition, the evacuation time map was newly utilized to investigate how the evacuation time for different SAHRR was affected by changing the various input parameters. In the previous studies, it was found that the OD is the most dominant variable to determine the MCR evacuation time. In this study, however, the evacuation time map showed that the HF is the most dominant factor at the condition of without-mechanical ventilation for the MCR with a partially-open false ceiling, but the OD is the most dominant factor for all the other conditions. Therefore, the method using the SAHRR and the evacuation time map was very useful to effectively and comprehensively evaluate the operator habitability for the various input parameters in the event of MCB fires for the reference MCR.

A Basic Study on Establishment of the Ecological Landscape Planning Model (경관생태계획 모형설정을 위한 기초적 연구)

  • Ra, Jung-hwa;Cho, Hyun-Ju;Lee, Hyun-Taek
    • Journal of the Korean Institute of Landscape Architecture
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    • v.36 no.4
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    • pp.48-64
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    • 2008
  • The aim of this research is to set a systemic Ecological Landscape Planning Model to cope with the destroyed landscape problems which was caused by massive development project and thoughtless development in country areas. The summary of research result are as follows. As a result of analysis on domestic and international literature, there are 60 planning index items which are nature conservation area, landscape conservation area, and build and manage wetland biotope and so on. total number of planning index is 34 after finalizing the physical index items. As a result of on-spot research, all 34 planning index after literature analysis is existing. Also, there are 38 finally-selected index which includes 4 added planning index in the process of research like natural vegetation in frequently-used spot. As a result of importance analysis on detailed planning index, most are above 5 points, which is relatively high. As a result of factor analysis on patterning for the detailed planning index, it was classified with seven elements. The first Ecological Landscape Planning model was set with integrated analysis on result of pattering for the detailed planning index and importance of detailed planning index. Based on first model, to make more systematic landscape, the analysis of MCB was conducted. As a result of MCB analysis according to planning index, it is confirmed that each planning index shows maximum. As a result of importance analysis on the 9 plans keynote, the average importance point was 4.62 for conservation area and 4.54 for enrichment area respectively. By integrating the result of importance analysis on basic aims of the first model, MCB analysis and plans, we set the second Ecological Landscape Planning model. In vertical transition, for example, 'conservation area' showed the importance point above 5.2 for all planning index except setting recreational space. Also, the analysis on parallel structure showed that relation between 'additional improvement, management, and connection' and other planning index is above 5.3 and importance on correlation with 'the part which should be protected from nature and landscape' marked 6.07 which is the highest.