The Experts below are selected from a list of 495087 Experts worldwide ranked by ideXlab platform
Ignacio E. Grossmann - One of the best experts on this subject based on the ideXlab platform.
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successive lp approximation for nonconvex blending in milp scheduling optimization using factors for qualities in the process industry
2018Co-Authors: Jeffrey D Kelly, Brenno C Menezes, Ignacio E. GrossmannAbstract:We develop a linear programming (LP) approach for nonlinear (NLP) blending of streams to approximate nonconvex Quality constraints by considering property variables as constants, parameters, or coefficients of qualities that we call factors. In a blend shop, these intensive properties of streams can be extended by multiplying the Material flow carrying out these amounts of qualities. Our proposition augments eQuality balance constraints as essentially cuts of Quality Material flow for each property specification in a mixing point between feed sources and product sinks. In the LP factor formulation, the product blend Quality is replaced by its property specification and variables of slacks and/or surpluses are included to close the balance; these are called factor flows and are well known in industry as product giveaways. Examples highlight the usefulness of factors in successive substitution by correcting nonlinear blending deltas in mixed-integer linear models (MILP) and to control product Quality giveaw...
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Successive LP Approximation for Nonconvex Blending in MILP Scheduling Optimization Using Factors for Qualities in the Process Industry
2018Co-Authors: Jeffrey D. Kelly, Brenno C Menezes, Ignacio E. GrossmannAbstract:We develop a linear programming (LP) approach for nonlinear (NLP) blending of streams to approximate nonconvex Quality constraints by considering property variables as constants, parameters, or coefficients of qualities that we call factors. In a blend shop, these intensive properties of streams can be extended by multiplying the Material flow carrying out these amounts of qualities. Our proposition augments eQuality balance constraints as essentially cuts of Quality Material flow for each property specification in a mixing point between feed sources and product sinks. In the LP factor formulation, the product blend Quality is replaced by its property specification and variables of slacks and/or surpluses are included to close the balance; these are called factor flows and are well known in industry as product giveaways. Examples highlight the usefulness of factors in successive substitution by correcting nonlinear blending deltas in mixed-integer linear models (MILP) and to control product Quality giveaways or premium specifications in blend shops
Christophe Ballif - One of the best experts on this subject based on the ideXlab platform.
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high efficiency microcrystalline silicon single junction solar cells
2013Co-Authors: Simon Hanni, Gregory Bugnon, Gaetano Parascandolo, Mathieu Boccard, Jordi Escarre, Matthieu Despeisse, F Meillaud, Christophe BallifAbstract:This short communication highlights our latest results towards high-efficiency microcrystalline silicon single-junction solar cells. By combining adequate cell design with high-Quality Material, a new world record efficiency was achieved for single-junction microcrystalline silicon solar cell, with a conversion efficiency of 10.69%, independently confirmed at ISE CalLab PV Cells. Such significant conversion efficiency could be achieved with only 1.8 µm of Si.
R Caballero - One of the best experts on this subject based on the ideXlab platform.
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investigation of cu in ga se2 thin film formation during the multi stage co evaporation process
2013Co-Authors: R Caballero, C A Kaufmann, Varvara Efimova, Thorsten Rissom, Volker Hoffmann, H W SchockAbstract:In order to transfer the potential for the high efficiencies seen for Cu(In,Ga)Se2 (CIGSe) thin films from co-evaporation processes to cheaper large-scale deposition techniques, a more intricate understanding of the CIGSe growth process for high-Quality Material is required. Hence, the growth mechanism for chalcopyrite-type thin films when varying the Cu content during a multi-stage deposition process is studied. Break-off experiments help to understand the intermediate growth stages of the thin-film formation. The film structure and morphology are studied by X-ray diffraction and scanning electron microscopy. The different phases at the film surface are identified by Raman spectroscopy. Depth-resolved compositional analysis is carried out via glow discharge optical emission spectrometry. The experimental results imply an affinity of Na for Material phases with a Cu-poor composition, affirming a possible interaction of sodium with Cu vacancies mainly via In(Ga)Cu antisite defects. An efficiency of 12.7% for vacancy compound-based devices is obtained. Copyright © 2011 John Wiley & Sons, Ltd.
Wmm Erwin Kessels - One of the best experts on this subject based on the ideXlab platform.
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local deposition of high purity pt nanostructures by combining electron beam induced deposition and atomic layer deposition
2010Co-Authors: Adriaan J. M. Mackus, Jjl Hans Mulders, Van De Mcm Richard Sanden, Wmm Erwin KesselsAbstract:An approach for direct-write fabrication of high-purity platinum nanostructures has been developed by combining nanoscale lateral patterning by electron beam induced deposition (EBID) with area-selective deposition of high Quality Material by atomic layer deposition (ALD). Because virtually pure, polycrystalline Pt nanostructures are obtained, the method extends the application possibilities of EBID, whereas compared to other area-selective ALD approaches, a much higher resolution is attainable; potentially down to sub-10 nm lateral dimensions.
Adriaan J. M. Mackus - One of the best experts on this subject based on the ideXlab platform.
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Nanopatterning by direct-write atomic layer deposition
2012Co-Authors: Adriaan J. M. Mackus, Saf Bas Dielissen, Jjl Hans Mulders, Wilhelmus M. M. KesselsAbstract:A novel direct-write approach is presented, which relies on area-selective atomic layer deposition on seed layer patterns deposited by electron beam induced deposition. The method enables the nanopatterning of high-Quality Material with a lateral resolution of only ∼10 nm. Direct-write ALD is a viable alternative to lithography-based patterning with a better compatibility with sensitive nanoMaterials.
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local deposition of high purity pt nanostructures by combining electron beam induced deposition and atomic layer deposition
2010Co-Authors: Adriaan J. M. Mackus, Jjl Hans Mulders, Van De Mcm Richard Sanden, Wmm Erwin KesselsAbstract:An approach for direct-write fabrication of high-purity platinum nanostructures has been developed by combining nanoscale lateral patterning by electron beam induced deposition (EBID) with area-selective deposition of high Quality Material by atomic layer deposition (ALD). Because virtually pure, polycrystalline Pt nanostructures are obtained, the method extends the application possibilities of EBID, whereas compared to other area-selective ALD approaches, a much higher resolution is attainable; potentially down to sub-10 nm lateral dimensions.
