• Title/Summary/Keyword: Break-In

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A Computer Simulation Study of an Automated Storage and Retrieval System (자동창고 시스템의 컴퓨터 시뮬레이션 연구)

  • Kim, Kwang-Soo;Choi, Young-Hwan
    • IE interfaces
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    • v.3 no.2
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    • pp.39-51
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    • 1990
  • One of the most important and powerful tools available for design and/or study of the operation of complex systems and processes is simulation. Since automated material handling systems like AS/RS are often quite complex, a network-based simulation model is developed to analyze an automobile part supplier's automated storage and retrieval system(AS/RS). The network simulation model is implemented in the SLAM Ⅱ on a VAX 8800 computer. Performance of the AS/RS was tested for 3 dispatching rules, 3 work load levels, 2 storage policies, 3 levels of stacker crane break-down, and 2 conveyor system layouts. Results indicate that the AS/RS performance is primarily affected by the dispatching rule and work load level.

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MOMENT-OF-FLUID METHOD FOR FREE SURFACE FLOW SIMULATION USING UNSTRUCTURED MESHES (비정렬 격자상에서 Moment-of-Fluid 방법을 이용한 자유표면유동계산)

  • Ahn, H.T.
    • 한국전산유체공학회:학술대회논문집
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    • 2011.05a
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    • pp.65-67
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    • 2011
  • The moment-of-fluid (MOF) method is a new volume-tracking method that accurately treats evolving material interfaces. The MOF method uses moment data, namely the material volume fraction, as well as the centroid, for a more accurate representation of the material configuration, interfaces and concomitant volume advection. In this paper, unstructured mesh extension of the MOF method is to be presented. The MOF method is coupled with a stabilized finite element incompressible Navier-Stokes solver for two materials. The effectiveness of the MOF method is demonstrated with a free-surface dam-break problem.

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A numerical study on the optimum size for the orifice located on the steam generator cassette of integral reactor (일체형원자로 증기발생기 카세트 하단에 설치된 오리피스의 최적설계 연구)

  • Kang Hyung Seok;Yoon Juhyeon;Kim Hwan Yeol;Cho Bong Hyun;Lee Doo Jeong
    • 한국전산유체공학회:학술대회논문집
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    • 1998.05a
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    • pp.75-81
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    • 1998
  • A new advanced integral reactor of 330 MWt capacity named SMART(System-integrated Modular Advanced ReacTor) is currently under development at KAERI(Korea Atomic Energy Research Institute). One of the major design features of the integral reactor is locating the steam generators(SG) inside reactor vessel and eliminating the possibility of LB LOCA(large Break Loss of Coolant Accident). Orifices are fitted at the low part of steam generator cassette to stabilize and balance coolant flow distribution in the MCP (Main Circulation Pump) pressure header. A sensitivity analysis is conducted to determine the optimum orifice size using computer code 'CFX'.

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New Functional Conductive Polymer Composites Containing Nickel Coated Carbon Black Reinforced Phenolic Resin

  • Farid El-Tantawy;Nadia Abdel Aal;Yong Kiel Sung
    • Macromolecular Research
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    • v.13 no.3
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    • pp.194-205
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    • 2005
  • The network structure of Ni-coated carbon black (NCB) composites filled with phenolic resin was investigated by means of using scanning electron microscopy, viscosity, interfacial tension, shrinkability, Flory-Huggins interaction parameters, and swelling index. The electrical properties of the composites have been characterized by measurement of the specific conductivity as a function of temperature. Additionally, the variation of conductivity with temperature for the composites has been reported and analyzed in terms of the dilution volume fraction, relative volume expansion, and barrier heights energy. The thermal stability of phenolic-NCB composites has been also studied by means of the voltage cycle processes. The experimental data of EMI wave shielding were analyzed and compared with theoretical calculations. The mechanical properties such as tensile strength, tensile modulus, hardness and elongation at break (EB) of NCB-phenolic resin composites were also investigated.

EFFECTS OF THE CULTURE FILTRATE OF PSEUDOMONAS SOLANACEARUM ON THE CALLUS AND CUTTING OF TOBACCO PLANT (담배 Callus 및 삽수에 대한 세균성마름병균 (Pseudomonas solanacearum) 배양여액의 처리효과)

  • Yi, Y.K.;Lee, J.Y.;Kim, J.H.
    • Journal of the Korean Society of Tobacco Science
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    • v.7 no.1
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    • pp.3-6
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    • 1985
  • The typical dark brown stripe symptom of bacterial wilt disease was observed in the cuttings of tobacco stem treated with the culture filtrate of virulent Pseudomonas solanaceamm. And the tobacco callus create.4 with that culture filtrate showed deterioration of the callus 2 days after the treatment. On the contrary, the cuttings and the callus treated with the culture filtrate of the avirulent bacteria expressed no typical symptom and vigorous growth respectively. Therefore it was suggested that certain toxin which might be produced by the virulent bacteria could break down tobacco cells.

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Discrimination of Acoustic Emission Signals using Pattern Recognition Analysis (형상인식법을 이용한 음향방출신호의 분류)

  • Joo, Y.S.;Jung, H.K.;Sim, C.M.;Lim, H.T.
    • Journal of the Korean Society for Nondestructive Testing
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    • v.10 no.2
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    • pp.23-31
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    • 1990
  • Acoustic Emission(AE) signals obtained during fracture toughness test and fatigue test for nuclear pressure vessel material(SA 508 cl.3) and artificial AE signals from pencil break and ultrasonic pulser were classified using pattern recognition methods. Three different classifiers ; namely Minimum Distance Classifier, Linear Discriminant Classifier and Maximum Likelihood Classifier were used for pattern recognition. In this study, the performance of each classifier was compared. The discrimination of AE signals from cracking and crack surface rubbing was possible and the analysis for crack propagation was applicable by pattern recognition methods.

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Structure-property relationship of melt intercalated maleated polyethylene nanocomposites

  • Reddy, M.M.;Gupta, Rahul K.;Bhattacharya, S.N.;Parthasarathy, R.
    • Korea-Australia Rheology Journal
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    • v.19 no.3
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    • pp.133-139
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    • 2007
  • Low density polyethylene nanocomposites were prepared by melt intercalating maleic anhydride grafted polyethylene and montmorillonite clay. It has been found that maleic anhydride has promoted strong interactions between polyethylene and montmorillonite, leading to the homogeneous dispersion of clay layers. Rheological experiments revealed that prepared nanocomposites exhibited shear thinning behaviour. Polyethylene nanocomposites exhibited an increase in steady shear viscosities compared to virgin polyethylene owing to strong polymer clay interactions. The tensile strength of nanocomposites was improved but elongation at break decreased considerably. Also, barrier properties improved significantly with montmorillonite content.

Comparison of the Spatial Variability of C- and L-Band Remotely Sensed Soil Moisture (원격측정 토양수분자료, (C-band 측정치 vs. L-band 측정치)의 공간변화도 비교)

  • Kim, Gwangseob;Lim, TaeKyung
    • Proceedings of the Korea Water Resources Association Conference
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    • 2004.05b
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    • pp.705-708
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    • 2004
  • The spatial variability of the L- and C- band large scale remotely sensed soil moisture data, obtained during tire Southern Great Plain 1999 (SGP'99), was characterized. The results demonstrate that soil moisture data using L-band show the break in statistical symmetry (multiscaling behavior) with the variation of scale of observation, which is similar to that of the soil property such as sand content. Also, soil moisture data using C-band show single scaling behavior with the variation of scale of observation, which Is similar to that of the vegetation condition.

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A Study on the Flame Propagating Speed Measurement-For the Laminar Flame- (火焰傳播速度測定에 關한 硏究 -層流火焰에 關하여-)

  • 조경국;정인석;허원욱
    • Journal of the korean Society of Automotive Engineers
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    • v.1 no.1
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    • pp.28-41
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    • 1979
  • Propane-Air premixed combustible gas was ignited by the conventional current break system inside the open combustion chamber under the atmospheric pressure and the room temperature to measure the flame propagating speed and the burning speed, also to elucidate the history of the propagating flame behavior and wall effects to flame shape by using Ion Gap Method and High Speed Schlieren Photography. The results obtained show that the maximum flame propagating speed and maximum burning speed are approximately 292 cm/sec and 36 cm/sec at the mixture ratio 4.6%, respectively. The cellular flame structures can be observable in the rich mixture region, moreover, the cellular structures become finer, with increasing the mixture strength.

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Next-Generation Personal Authentication Scheme Based on EEG Signal and Deep Learning

  • Yang, Gi-Chul
    • Journal of Information Processing Systems
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    • v.16 no.5
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    • pp.1034-1047
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    • 2020
  • The personal authentication technique is an essential tool in this complex and modern digital information society. Traditionally, the most general mechanism of personal authentication was using alphanumeric passwords. However, passwords that are hard to guess or to break, are often hard to remember. There are demands for a technology capable of replacing the text-based password system. Graphical passwords can be an alternative, but it is vulnerable to shoulder-surfing attacks. This paper looks through a number of recently developed graphical password systems and introduces a personal authentication system using a machine learning technique with electroencephalography (EEG) signals as a new type of personal authentication system which is easier for a person to use and more difficult for others to steal than other preexisting authentication systems.