Search results for "Simulation"

showing 10 items of 5095 documents

Un outil pour les politiques scolaires: "Prospective scolaire"

2012

Today, territorial, demographic evolutions can be quick, which encourages towns to reconsider the geography of public services. This is notably the case of General Councils that handle the localisation of public middle schools and establish school sectors. Carrying out these tasks requires taking into account several parameters: demographic dynamics, urban projects, social diversity within schools, and transportation conditions. The tool 'Prospective Scolaire' integrates these multiple data in order to help communities carry out their tasks.

Aide à la décisionProspectiveScolaire[SHS.GEO] Humanities and Social Sciences/GeographyOutilMathematical geography. Cartography[SHS.GEO]Humanities and Social Sciences/GeographyGA1-1776Simulation[ SHS.GEO ] Humanities and Social Sciences/Geography
researchProduct

Effects of Air Tightness Tests on Steel Thin-Wall Box Structures with Circular and Rectangular Cross Sections

2019

In this paper, the effects of air tightness tests on steel box structures with rectangular or circular cross sections typical of port cranes (legs, arms, and crosspieces) are analyzed. Legs and arms are generally made with elements with profiles having a square or rectangular cross section, while the diagonal struts are made with profiles having circular cross sections. To verify the air tightness of these elements, a necessary requirement to protect them from corrosion if they are not protected with other protection techniques, air tightness tests are performed. These tests, in the framework of durability tests, must be carried out while maintaining the structure elasticity well below the …

Air tightnessMaterials sciencebusiness.industrytechnology industry and agriculturePort (circuit theory)Building and ConstructionStructural engineeringNumerical simulationChoice of test pressurebody regionsSettore ICAR/09 - Tecnica Delle CostruzioniBox profiles with rectangular or circular sectionArts and Humanities (miscellaneous)Thin wallSeal testbusinessCivil and Structural Engineering
researchProduct

Aspen Plus process-simulation model: Producing biogas from VOC emissions in an anaerobic bioscrubber

2018

A process-simulation model for a novel process consisted of an anaerobic bioscrubber was developed in Aspen Plus®. A novel approach was performed to implement the anaerobic reactor in the simulation, enabling it to be connected to the scrubber. The model was calibrated and validated using data from an industrial prototype that converted air emissions polluted with volatile organic compounds with an average daily concentration of 1129 mgC Nm−3 into bioenergy for more than one year. The scrubber, which showed a removal efficiency within 83-93%, was successfully predicted with an average absolute relative error of 5.2 ± 0.08% using an average height-to-theoretical-plate value of 1.05 ± 0.08 m …

Aire DepuracióEnvironmental Engineering020209 energyScrubber02 engineering and technology010501 environmental sciencesManagement Monitoring Policy and Law01 natural sciencesBioreactorsBiogasBioenergy0202 electrical engineering electronic engineering information engineeringBioreactorGas Aparells i instrumentsAnaerobiosisProcess simulationWaste Management and Disposal0105 earth and related environmental sciencesVolatile Organic CompoundsChemical oxygen demandGeneral MedicinePulp and paper industryBiofuelBiofuelsEnvironmental scienceMethaneAnaerobic exerciseJournal of Environmental Management
researchProduct

An algebraic multigrid based shifted-Laplacian preconditioner for the Helmholtz equation

2007

A preconditioner defined by an algebraic multigrid cycle for a damped Helmholtz operator is proposed for the Helmholtz equation. This approach is well suited for acoustic scattering problems in complicated computational domains and with varying material properties. The spectral properties of the preconditioned systems and the convergence of the GMRES method are studied with linear, quadratic, and cubic finite element discretizations. Numerical experiments are performed with two-dimensional problems describing acoustic scattering in a cross-section of a car cabin and in a layered medium. Asymptotically the number of iterations grows linearly with respect to the frequency while for lower freq…

Algebraic multigrid methodPhysics and Astronomy (miscellaneous)Helmholtz equationGMRESMathematics::Numerical Analysissymbols.namesakeMultigrid methodQuadratic equationHelmholtz equationäärellisten elementtien menetelmäMathematicsNumerical AnalysisPreconditionerApplied MathematicspohjustinMathematical analysisAlgebrallinen multigrid-menetelmäHelmholzin yhtälöComputer Science::Numerical AnalysisGeneralized minimal residual methodFinite element methodComputer Science ApplicationselementtimenetelmäComputational MathematicsModeling and SimulationHelmholtz free energysymbolsPreconditionerLaplace operatorJournal of Computational Physics
researchProduct

A damping preconditioner for time-harmonic wave equations in fluid and elastic material

2009

A physical damping is considered as a preconditioning technique for acoustic and elastic wave scattering. The earlier preconditioners for the Helmholtz equation are generalized for elastic materials and three-dimensional domains. An algebraic multigrid method is used in approximating the inverse of damped operators. Several numerical experiments demonstrate the behavior of the method in complicated two-dimensional and three-dimensional domains. peerReviewed

Algebraic multigrid methodPhysics and Astronomy (miscellaneous)Helmholtz equationGMRESNavier equationMathematics::Numerical AnalysisMultigrid methodHelmholtz equationäärellisten elementtien menetelmäMathematicsElastic scatteringNumerical AnalysisNavierin yhtälöPreconditionerApplied MathematicsMathematical analysispohjustinAcoustic waveWave equationAlgebrallinen multigrid-menetelmäHelmholzin yhtälöGeneralized minimal residual methodComputer Science::Numerical AnalysisFinite element methodComputer Science ApplicationselementtimenetelmäComputational MathematicsClassical mechanicsModeling and SimulationPreconditioner
researchProduct

An improved algorithm for thermal dynamic simulation of walls using Z-transform coefficients

2003

The Transfer Function Method (TFM), recommended by American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE), is one of the most modern tools available to solve heat transfer problems in building envelopes and environments. TFM utilises Z-transform to solve the equations system that describes the heat transfer in a multi-layered wall. Due to an analogy with an electric circuit, it is possible to write the equations system in a matrix suitable to be solved by computer. Authors carried out an analysis on an historical building placed in the south of Italy to test the reliability and the quality of the thermal dynamic simulation using TFM. The analysis is performed usi…

AlgorithmProblem solvingSettore ING-IND/11 - Fisica Tecnica AmbientaleMathematical operatorTransfer functionsBuildingMathematical transformationComputer simulationMatrix algebra
researchProduct

Waveguiding properties of a photonic crystal fiber with a solid core surrounded by four large air holes

2009

The polarization-dependent guiding properties of a hexagonal-lattice photonic crystal fiber with a solid-core surrounded by four large air holes are investigated. The appearance of a polarization dependent cutoff frequency, together with several parameters as the birefringence, the modal effective area, the group velocity dispersion and the polarization dependent loss are analyzed. A collection of fibers with different structural parameters were fabricated and characterized. An effective anti-guide structure from at least 450 nm to 1750 nm, a polarizing fiber with a polarization dependent loss of 16 dB/m at 1550 nm, and an endlessly singlemode polarization-maintaining fiber with group biref…

All-silica fiberMaterials scienceOptical fiberPhysics::OpticsPolarization-maintaining optical fiberSensitivity and SpecificityGraded-index fiberlaw.inventionDouble-clad fiberOpticslawScattering RadiationDispersion-shifted fiberComputer SimulationOptical FibersPhotonsbusiness.industryReproducibility of ResultsEquipment DesignMicrostructured optical fiberModels TheoreticalÒpticaAtomic and Molecular Physics and OpticsEquipment Failure AnalysisComputer-Aided DesignOptoelectronicsCristallsCrystallizationbusinessPhotonic-crystal fiber
researchProduct

GRASP with exterior path-relinking and restricted local search for the multidimensional two-way number partitioning problem

2017

In this work, we tackle multidimensional two-way number partitioning (MDTWNP) problem by combining GRASP with Exterior Path Relinking. In the last few years, the combination of GRASP with path relinking (PR) has emerged as a highly effective tool for finding high-quality solutions for several difficult problems in reasonable computational time. However, in most of the cases, this hybridisation is limited to the variant known as interior PR. Here, we couple GRASP with the "exterior form" of path relinking and perform extensive experimentation to evaluate this variant. In addition, we enhance our GRASP with PR method with a novel local search method specially designed for the MDTWNP problem. …

Alternative methodsMathematical optimization021103 operations researchGeneral Computer Sciencebusiness.industryGRASP0211 other engineering and technologies02 engineering and technologyManagement Science and Operations ResearchModeling and SimulationPath (graph theory)0202 electrical engineering electronic engineering information engineeringLocal search procedure020201 artificial intelligence & image processingLocal search (optimization)businessDescent (mathematics)MathematicsComputers & Operations Research
researchProduct

Identification of a new series of amides as non-covalent proteasome inhibitors

2014

Proteasome inhibition has emerged as an important therapeutic strategy for the treatment of multiple myeloma (MM) and some forms of lymphoma, with potential application in other types of cancers. 20S proteasome consists of three different catalytic activities known as chymotrypsin-like (ChT-L), trypsin-like (T-L), and, post-glutamyl peptide hydrolyzing (PGPH) or caspase-like (C-L), which are located respectively on the β5, β2, and β1 subunits of each heptameric β rings. Currently a wide number of covalent proteasome inhibitors are reported in literature; however, the less widely investigated non-covalent inhibitors might be a promising alternative to employ in therapy, because of the lack o…

AmideMagnetic Resonance SpectroscopyStereochemistryProtein subunitPeptideMolecular Docking SimulationDrug DiscoverymedicineHumansProteasome inhibitorDocking studiesMultiple myelomaPharmacologychemistry.chemical_classificationOrganic ChemistryGeneral Medicinemedicine.diseaseAmidesYeastMolecular Docking SimulationchemistryProteasomeBiochemistryNon-covalent inhibitorDocking (molecular)Covalent bondProteasome Inhibitors
researchProduct

Synthesis and biological activities of a new class of heat shock protein 90 inhibitors, designed by energy-based pharmacophore virtual screening

2013

The design through energy-based pharmacophore virtual screening has led to aminocyanopyridine derivatives as efficacious new inhibitors of Hsp90. The synthesized compounds showed a good affinity for the Hsp90 ATP binding site in the competitive binding assay. Moreover, they showed an excellent antiproliferative activity against a large number of human tumor cell lines. Further biological studies on the derivative with the higher EC50 confirmed its specific influence on the cellular pathways involving Hsp90.

AminopyridinesInhibitory Concentration 50Structure-Activity RelationshipUser-Computer InterfaceHeat shock proteinCell Line TumorSettore BIO/10 - BiochimicaDrug DiscoveryHumansHSP90 Heat-Shock ProteinsBinding siteVirtual screeningheat shock protein 90 inhibitors energy-based pharmacophore virtual screening cell cycle antiproliferative activitybiologyChemistryHsp90Combinatorial chemistrySettore CHIM/08 - Chimica FarmaceuticaHuman tumorMolecular Docking SimulationCell cultureDrug DesignEnergy basedbiology.proteinMolecular MedicinePharmacophoreDrug Screening Assays Antitumor
researchProduct