• Title, Summary, Keyword: pressure integration

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A Study on the Controller of Integration Smoke Control System (통합 제연시스템의 컨트롤러 개발에 관한 연구)

  • Lee, Dong-Myung
    • Fire Science and Engineering
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    • v.20 no.1
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    • pp.77-82
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    • 2006
  • This study defined engineering mechanism and compensation method to establish reference pressure of smoke control zone with atmospheric pressure that is compensated for temperature. The reliable controller of integration smoke control was developed by establishing the specifications, algorithms and constructing engineering data. The development of controller for integration smoke control can cut down number of processes, manufacturing and installation cost by removing pressure measurement pipe established separately for non smoke control zone, and improve the accuracy of pressure differential by embedding pressure measurement ports for non smoke control zone. More correct and reliable pressure differentials can be obtained by the central control from controller of integration smoke control rather than the existent individual control. This will provide the basics and the flexibility to the integral smoke control system and accordingly improve the performance of disaster prevention.

The Study on the Determination of the Contact Area of the Circular Plate Resting on Elastic Half-space under Axisymmetric Loading (탄성지반 위의 축대칭 하중을 받는 원판의 접촉응력 해석에 관한 연구)

  • 조현영;정진환;김성철
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • pp.87-94
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    • 1997
  • The circular plate resting on Boussinesq's half-space model under axisymmetric loading is studied by a finite element procedure to evaluate the distribution of contact pressure between plate and elastic half-space. The displacement of half-space due to axisymmetric surface loading can be evaluated by double integration of Boussinesq's solution. On that case the analytical integration can be executed for the radial direction but the analytical integration for the circumferential direction is impossible and the numerical integration should be considered. With the radial integration we can get non-dimensional function. Then the numerical integration for the formula is executed for the circumferential direction and the results are approximated 5th order Polynomials by using the least square method. With these 5th order approximate formula, the flexibility matrix of half-space is constructed as the coefficient matrix of nodal contact pressure by the finite element procedures. Iteration procedures are attempted by using this method to determine the separated region.

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Solid Propellants for Propulsion System Including a Yellow Iron Oxide (황색산화철을 포함하는 혼합형 추진제의 특성에 관한 연구)

  • Park, Sungjun;Won, Jongung;Park, Jungho;Park, Euiyong;Choi, Sunghan
    • Journal of the Korean Society of Propulsion Engineers
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    • v.22 no.3
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    • pp.65-71
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    • 2018
  • There is no significant difference in the initial viscosity of a propellant applied with yellow iron oxide and red iron oxide. In addition, the thermal decomposition rate of the material with added yellow iron oxide is faster than that with the addition of red iron oxide. Specifically, it was confirmed that the pressure exponent was 18% lower at high temperature and high pressure with yellow iron oxide than with red iron oxide. The initial viscosity was lowest at 71% of the large particle to small particle ratio.

Misfire Detection of a Gasoline Engine by Analysis of the Variation of Pressure in the Exhaust Manifold (배기관 내 압력 변동 분석에 의한 가솔린 기관의 실화 검출)

  • 심국상;복중혁;김세웅
    • Transactions of the Korean Society of Automotive Engineers
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    • v.7 no.5
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    • pp.1-8
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    • 1999
  • This paper describes the method for detection of the misfired cylinder by analysis of the variation of pressure occurred in exhaust manifold on an MPI gasoline engine. Misfired cylinder(s) cause a loss of power, an increase of fuel consumption and exhaust emission and vibration is caused by unsteady torque. Therefore early detection and correction of misfired cylinder(s) play a very important role in the proper performance and the exhaust emission. The method is a comparison of integration pressure index during the period of a blowdown in the displacement period. Experimental results showed that the method, using the variation of pressure in the exhaust manifold is proven to be effective in the detection of single cylinder or multiple cylinders misfire on the gasoline engine regardless of the engine revolutions. In addition, this method, using the variation of pressure in the exhaust manifold is a very easy and accurate method compared with other methods.

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Development of Digital Vacuum Pressure Sensor Using MEMS Analog Pirani Gauge

  • Cho, Young Seek
    • Journal of information and communication convergence engineering
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    • v.15 no.4
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    • pp.232-236
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    • 2017
  • A digital vacuum pressure sensor is designed, fabricated, and characterized using a packaged MEMS analog Pirani gauge. The packaged MEMS analog Pirani gauge requires a current source to heat up a heater in the Pirani gauge. To investigate the feasibility of digitization for the analog Pirani gauge, its implementation is performed with a zero-temperature coefficient current source and microcontroller that are commercially available. The measurement results using the digital vacuum pressure sensor showed that its operating range is 0.05-760 Torr, which is the same as the measurement results of the packaged MEMS analog pressure sensor. The results confirm that it is feasible to integrate the analog Pirani gauge with a commercially available current source and microcontroller. The successful hybrid integration of the analog Pirani gauge and digital circuits is an encouraging result for monolithic integration with a precision current source and ADCs in the state of CMOS dies.

Design Optimization of an Automotive Injection Molded Part for Minimizing Injection Pressure and Preventing Weldlines (사출압력 최소화와 웰드라인 방지를 위한 자동차용 사출성형 부품의 최적설계)

  • Park, Chang-Hyun;Pyo, Byung-Gi;Choi, Dong-Hoon;Koo, Man-Seo
    • Transactions of the Korean Society of Automotive Engineers
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    • v.19 no.1
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    • pp.66-72
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    • 2011
  • Injection pressure is an important factor in filling procedure for injection molded parts. In addition, weldlines should be avoided to successfully produce injection molded parts. In this study, we optimally obtained injection molding process parameters that minimize injection pressure. Then, we determined the thickness of the part to avoid weldlines. To solve the optimization problem proposed, we employed MAPS-3D (Mold Analysis and Plastics Solution-3 Dimension), a commercial CAE tool for injection molding analysis, and PIAnO (Process Integration, Automation, and Optimization) as a commercial PIDO (Process Integration and Design Optimization) tool. We integrated MAPS-3D into PIAnO, automated the analysis and design procedure, and performed optimization by employing PQRSM (Progressive Quadratic Response Surface Method) equipped in PIAnO. We successfully obtained optimization results, which demonstrates the effectiveness of our design method.

Evaluations on a Pressure-Field Calculation Method using PIV Synthetic Image (가상영상 PIV기반 압력장 계산법 평가)

  • Lee, Chang Je;Cho, Gyong Rae;Kim, Uei Kan;Kim, Dong Hyuk;Doh, Deog Hee
    • Journal of the Korean Society of Visualization
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    • v.14 no.2
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    • pp.46-51
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    • 2016
  • In this study, a Masked Omni-Directional Integration(MODI) method for pressure calculation is proposed using the Particle Image Velocimetry (PIV) data. To obtain the velocity field, the Affine PIV method was adopted. Synthetic images were generated for a solid body rotation. Calculation on the pressure was based on the Navier-Stokes equation. The results obtained by the MODI were compared with those obtained by theoretical pressure and by the Omni-Directional Integration(ODI) method. It was shown that the minimum error by the proposed MODI method was attained when the mask size was 1.

Drivers Influencing Demand Chain Integration Strategy: Analysis of Intelligent Collaboration Cases (수요사슬 통합전략에 영향을 미치는 동인에 관한 연구: 지능형 협업 사례 분석)

  • Kim Yon Tae;Kim Chulsoo
    • Journal of Intelligence and Information Systems
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    • v.10 no.2
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    • pp.189-209
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    • 2004
  • The collaboration between businesses in a demand chain has three layers: Integration, Exchange, and Synchronize. The latter the layer is, the stronger the collaboration gets. This paper investigated drivers influencing intelligent demand chain integration strategy (supply integration, demand integration, demand chain integration) in Korea manufacturing and services. The drivers are classified into two types: rational efficiency driven and bandwagon driven. We find tile differences in the characteristics of drivers affecting the strategies. Besides, this study suggests the better integration strategy for Korea firms. In conclusion it says that demand integration strategy is chosen to improve efficiency, whereas supply integration strategy is influenced by external pressure.

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Gate Locations Optimization of an Automotive Instrument Panel for Minimizing Cavity Pressure (금형 내부 압력 최소화를 위한 자동차 인스트루먼트 패널의 게이트 위치 최적화)

  • Cho, Sung-Bin;Park, Chang-Hyun;Pyo, Byung-Gi;Cho, Dong-Hoon
    • Journal of the Korean Society for Precision Engineering
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    • v.29 no.6
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    • pp.648-653
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    • 2012
  • Cavity pressure, an important factor in injection molding process, should be minimized to enhance injection molding quality. In this study, we decided the locations of valve gates to minimize the maximum cavity pressure. To solve this problem, we integrated MAPS-3D (Mold Analysis and Plastic Solution-3Dimension), a commercial injection molding analysis CAE tool, using the file parsing method of PIAnO (Process Integration, Automation and Optimization) as a commercial process integration and design optimization tool. In order to reduce the computational time for obtaining the optimal design solution, we performed an approximate optimization using a meta-model that replaced expensive computer simulations. To generate the meta-model, computer simulations were performed at the design points selected using the optimal Latin hypercube design as an experimental design. Then, we used micro genetic algorithm equipped in PIAnO to obtain the optimal design solution. Using the proposed design approach, the maximum cavity pressure was reduced by 17.3% compared to the initial one, which clearly showed the validity of the proposed design approach.