In order to reduce danger and cost in physical chemical process training and testing, this paper proposed a chemical process simulation system based on distributed virtual reality technology. According to characters o...
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Multi-crystalline silicon ingots produced using directional solidification systems (DSS) represent the best way to obtain high quality crystalline silicon at low prices and with high throughputs. The DSS technology is...
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ISBN:
(纸本)9781424499663
Multi-crystalline silicon ingots produced using directional solidification systems (DSS) represent the best way to obtain high quality crystalline silicon at low prices and with high throughputs. The DSS technology is widespread among PV silicon ingot producers and hundreds of furnaces are manufactured worldwide every year. The present challenge for crystal growers is to increase the maximum ingot mass in order to benefit from scale economy profits and to reduce energy consumption. This reason has pushed some companies to develop new DSS furnaces able to grow ingots up to 650 kg. As a matter of fact, the increase in size defines new challenges in design and process optimization due of the intensification of radial thermal instabilities and consequently of buoyancy driven flows in the melt [1]. These phenomena are related to heat and mass transfer during the solidification process and are important to control both the liquid/solid interface shape and the impurities distribution in the crystal [2,3,4,5,6]. The main features and the characteristic design of the hot-zone in the iDSS (induction-DSS) furnace are taken into account, especially in comparison with the standard DSSs ones. The reduction in thickness of the insulation boards and the smaller size of the hot-zone itself, together with the selective lateral induction coil system, all lead to an optimal control of the thermal instabilities into the silicon melt, increasing the ingot quality. In fact, the lateral induction coil system equipped with independent turns connections can be used to force selectively - at different vertical positions - the most suitable thermal condition. In this way one is able to compensate the radiative thermal losses and create a "virtual" adiabatic wall, producing a perfectly planar solidification front or modeling the radial thermal gradient in order to obtain the desired solidification front shapes. The results from a set of electro-magnetic, thermal and fluid-dynamic simulation are
The terrorist attacks of September 11, 2001 crystallized public awareness and concern over issues of aviation security. As the nation has brought greater levels of inspection and other security measures to bear on pas...
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ISBN:
(纸本)9781424474004
The terrorist attacks of September 11, 2001 crystallized public awareness and concern over issues of aviation security. As the nation has brought greater levels of inspection and other security measures to bear on passengers and baggage, concerns have mounted that air cargo will become vulnerable to delivering explosive threats to aircraft. In the "9/11" bill, Congress mandated TSA to screen 50% of air cargo on passenger-carrying aircraft by February 2009 and 100% by August 2010. Therefore, TSA will eliminate all exemptions to screening cargo, resulting in an increased amount of cargo subject to mandatory screening. Oak Ridge National Laboratory's (ORNL's) Enterprise modeling and Analysis (EMA) tool is being used to help TSA meet its air cargo screening mandates. ORNL is developing defensible cost estimates for implementing optimal screening systems at the top ten passenger airports and top five all-cargo airports. EMA is used to determine optimal screening strategies (maximum affinity, minimum cost) and to estimate life-cycle costs. This paper details the EMA framework and its integrated optimization-and lifecycle-based modeling approach. The EMA system balances security system effectiveness and costs driven by local air cargo mix, priority, volume, and packaging and consolidation configurations and infrastructure, operations, and business constraints.
Oceaneering has developed highly reliable contact physics simulation systems in support of the ultra-deepwater oil and gas industry. This paper provides an overview of how simulation is used offshore, explains Oceanee...
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In this paper, a new data-driven model predictive control (MPC) is considered based on bilinear subspace identification. The system's nonlinear behavior is described with a bilinear subspace predictor structure in...
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The paper presents the dynamic modeling and coordinated control strategy for an integrated micro grid scheme using Photo Voltaic PV, Fuel Cell FC, and backup Diesel generation with additional battery backup system. Th...
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Complex manufacture collaborative design process is a dynamic process with uncertainty, which is a process with multi-task executing in a parallel manner. It has obviously time constraint, which has been few studied u...
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ISBN:
(纸本)9780878492329
Complex manufacture collaborative design process is a dynamic process with uncertainty, which is a process with multi-task executing in a parallel manner. It has obviously time constraint, which has been few studied up to now. Temporary inference and simulation problem for complex manufacture design process are mainly studied in this paper. Firstly, a Petri net model for collaborative design process is proposed based on time Petri net theory and four temporary inference algorithms of ordering, paralleling, selecting and circling structures in collaborative design process. Secondly, the authors design and develop a visually modeling and simulating circumstance for collaborative design process temporary inference based on time Petri net. Temporary inference for the whole collaborative design process and optimization to design task can be implemented by this simulation software. Finally, collaborative design process for driver of chain-transportation-driven equipment is undertaken to shown the efficiency of the proposed method. Research in this paper affords a determinant principle for time arrangement of collaborative design task and it also affords schema scheduling.
A reliable algorithm for computationally efficient simulation-driven design optimization of microwave structures is introduced. Our approach exploits manifold mapping (MM), a response correction technique that aligns ...
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A reliable algorithm for computationally efficient simulation-driven design optimization of microwave structures is introduced. Our approach exploits manifold mapping (MM), a response correction technique that aligns the coarse model (computationally cheap representation of the structure under consideration) with the accurate but CPU-intensive (fine) model of the optimized device. MM model does not use any extractable parameters which makes it easy to implement. Efficiency and excellent convergence properties of the proposed algorithm is demonstrated through the design of several microstrip filters.
simulation-driven design of a 2.45 GHz quasi-Yagi antenna is presented that exploits a coarse-discretization antenna model and surrogate-based optimization algorithm. The design objectives include maximum directivity ...
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simulation-driven design of a 2.45 GHz quasi-Yagi antenna is presented that exploits a coarse-discretization antenna model and surrogate-based optimization algorithm. The design objectives include maximum directivity of the principal polarization, input impedance, side lobe level, front-to-back ratio, and direction of maximal radiation. The computation cost of the design process is low because most of the operations are performed on the coarse-discretization model, whereas the high-fidelity simulation is only used for setting up and updating the surrogate model, as well as for design verification.
The proceedings contain 450 papers. The topics discussed include: a 0.8-1.5 GHz multi-standard WCDMA receiver with an inter-stage tunable notch filter;a BPSK/QPSK receiver architecture suitable for low-cost ultra-high...
ISBN:
(纸本)9782874870163
The proceedings contain 450 papers. The topics discussed include: a 0.8-1.5 GHz multi-standard WCDMA receiver with an inter-stage tunable notch filter;a BPSK/QPSK receiver architecture suitable for low-cost ultra-high rate 60 GHz wireless communications;complex 2D discontinuities analysis using hybrid finite element method and a modified multimodal variational formulation-application to filter design;wideband TLM modeling of microwave structures with anisotropic and dispersive media;a SPDT switch in a standard 45 nm CMOS process for 94 GHz applications;reliable simulation-driven microwave design optimization using manifold mapping;a miniaturized L-band 4-bit differential VGA using resistance-selectable bridged-T attenuators for a fine tuning of gain;a super-compact dual-band Wilkinson power divider composed of multi-layered CRLH transmission lines;and a triple-band SiGe HBT differential VCO using a reconfigurable multi-band resonator.
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