Search results for "Hard"

showing 10 items of 2294 documents

Muon identification with the ATLAS Tile Calorimeter Read-Out Driver for Level-2 trigger purposes

2008

The Hadronic Tile Calorimeter (TileCal) at the ATLAS experiment is a detector made out of iron as passive medium and plastic scintillating tiles as active medium. The light produced by the particles is converted to electrical signals which are digitized in the front-end electronics and sent to the back-end system. The main element of the back-end electronics are the VME 9U Read-Out Driver (ROD) boards, responsible of data management, processing and transmission. A total of 32 ROD boards, placed in the data acquisition chain between Level-1 and Level-2 trigger, are needed to read out the whole calorimeter. They are equipped with fixed-point Digital Signal Processors (DSPs) that apply online …

Digital signal processorCalorimeter (particle physics)Physics::Instrumentation and Detectorsbusiness.industryComputer scienceATLAS experimentDetectorData acquisitionTransmission (telecommunications)High Energy Physics::ExperimentElectronicsDetectors and Experimental TechniquesbusinessComputer hardwareDigital signal processing2008 IEEE Nuclear Science Symposium Conference Record
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Portable Video Supercomputing

2004

As inexpensive imaging chips and wireless telecommunications are incorporated into an increasing array, of portable products, the need for high efficiency, high throughput embedded processing will become an important challenge in computer architecture. Videocentric applications, such wireless videoconferencing, real-time video enhancement and analysis, and new, immersive modes of distance education, will exceed the computational capabilities of current microprocessor and digital signal processor (DSP) architectures. A new class of embedded computers, portable video supercomputers, will combine supercomputer performance with the energy efficiency required for deployment in portable systems. …

Digital signal processorComputer scienceData parallelismVideo processingSupercomputerTheoretical Computer ScienceMicroarchitectureMPEG encodinglaw.inventionMicroprocessorComputational Theory and MathematicsComputer architectureHardware and ArchitecturelawSIMDSoftware
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Simulations of non-spherical particles suspended in a shear flow

2000

The lattice-Boltzmann method was used to investigate the effects of the shape and concentration of the particles on the rheological properties of non-Brownian suspensions for non-zero Reynolds numbers. Several case studies were analyzed and the methods used were found to give accurate predictions for these systems. The viscosity of suspensions of both spherical and non-spherical particles was determined as functions of shear rate and concentration of particles. It was shown that, for high shear rates, shear thickening appears. This phenomenon is particularly pronounced for particles of irregular shape.

DilatantMaterials scienceLattice Boltzmann methodsGeneral Physics and AstronomyThermodynamicsReynolds numberMechanicsShear ratePhysics::Fluid DynamicsCondensed Matter::Soft Condensed Mattersymbols.namesakeShear (geology)RheologyHardware and ArchitecturesymbolsShear flowBrownian motion
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Damage and plasticity at the interfaces in composite materials and structures

2009

Abstract The structural behavior at the interface between two surfaces of ductile, brittle or quasi-brittle materials is studied by a new analytical elastoplastic damaging model. The model is developed in the framework of a thermodynamically consistent theory. The Helmholtz free energy is written to predict the materials’ hardening or softening. An isotropic damage is considered and the possible effects of dilatancy are taken into account including non-associative flow rules. The interface laws are presented both in a rate and a discrete incremental form. The analytical formulation is then implemented into a finite element code and two structural members are studied to validate the model. T…

DilatantMaterials sciencebusiness.industryMechanical EngineeringIsotropyComputational MechanicsGeneral Physics and AstronomyStructural engineeringPlasticityStrain hardening exponentFinite element methodComputer Science Applicationssymbols.namesakeBrittlenessinterface damage plasticity coupling biphaseMechanics of MaterialsHelmholtz free energyHardening (metallurgy)symbolsSettore ICAR/08 - Scienza Delle CostruzionibusinessComputer Methods in Applied Mechanics and Engineering
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The β-relaxation amplitudes for a dipolar hard sphere glass

1998

Abstract The β-relaxation amplitudes h m l , l ′ ( q ) for a dipolar hard sphere model are calculated in the diagonalization approximation up to l =1. The relevance to experimental difficulties to detect the characteristic β-relaxation minimum in dielectric loss measurements is discussed. Additionally, the microscopic nature of the β-relaxation of the rotational components is investigated by discussing the amplitudes in real space at different temperatures and densities.

DipoleAmplitudeCondensed matter physicsChemistryRelaxation (NMR)Materials ChemistryCeramics and CompositesDielectric lossHard spheresCondensed Matter PhysicsSpace (mathematics)Electronic Optical and Magnetic MaterialsJournal of Non-Crystalline Solids
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On the hardness of optimization in power-law graphs

2008

Our motivation for this work is the remarkable discovery that many large-scale real-world graphs ranging from Internet and World Wide Web to social and biological networks appear to exhibit a power-law distribution: the number of nodes y"i of a given degree i is proportional to i^-^@b where @b>0 is a constant that depends on the application domain. There is practical evidence that combinatorial optimization in power-law graphs is easier than in general graphs, prompting the basic theoretical question: Is combinatorial optimization in power-law graphs easy? Does the answer depend on the power-law exponent @b? Our main result is the proof that many classical NP-hard graph-theoretic optimizati…

Discrete mathematicsGeneral Computer ScienceVertex coverPower-law graphsGraph construction algorithmsClique (graph theory)Theoretical Computer ScienceCombinatoricsIndifference graphDominating setChordal graphIndependent setNP-hardnessCombinatorial optimizationGraph optimization problemsMaximal independent setMathematicsComputer Science(all)Theoretical Computer Science
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Vector-valued analytic functions of bounded mean oscillation and geometry of Banach spaces

1997

When dealing with vector-valued functions, sometimes is rather difficult to give non trivial examples, meaning examples which do not come from tensoring scalar-valued functions and vectors in the Banach space, belonging to certain classes. This is the situation for vector valued BMO. One of the objectives of this paper is to look for methods to produce such examples. Our main tool will be the vector-valued extension of the following result on multipliers, proved in [MP], which says that the space of multipliers between H and BMOA can be identified with the space of Bloch functions B, i.e. (H, BMOA) = B (see Section 3 for notation), which, in particular gives that g ∗ f ∈ BMOA whenever f ∈ H…

Discrete mathematicsGeneral MathematicsInfinite-dimensional vector functionBanach space46J15Banach manifoldHardy space30G30Bounded mean oscillationBounded operatorsymbols.namesake46B2046E40symbolsInterpolation space46B28Lp spaceMathematics
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Fixed point results for F-contractive mappings of Hardy-Rogers-type

2014

Recently, Wardowski introduced a new concept of contraction and proved a fixed point theorem which generalizes Banach contraction principle. Following this direction of research, in this paper, we will present some fixed point results of Hardy-Rogers-type for self-mappings on complete metric spaces or complete ordered metric spaces. Moreover, an example is given to illustrate the usability of the obtained results.

Discrete mathematicsGeneral MathematicsInjective metric spaceMetric spaces ordered metric spaces fixed points F-contractions of Hardy-Rogers-typeFixed-point theoremFixed pointFixed-point propertyConvex metric spaceUniform continuitySettore MAT/05 - Analisi MatematicaFréchet spaceContraction mappingMathematicsFilomat
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Application of kolmogorov complexity to inductive inference with limited memory

1995

A b s t r a c t . We consider inductive inference with limited memory[l]. We show that there exists a set U of total recursive functions such that U can be learned with linear long-term memory (and no short-term memory); U can be learned with logarithmic long-term memory (and some amount of short-term memory); if U is learned with sublinear long-term memory, then the short-term memory exceeds arbitrary recursive function. Thus an open problem posed by Freivalds, Kinber and Smith[l] is solved. To prove our result, we use Kolmogorov complexity.

Discrete mathematicsHardware_MEMORYSTRUCTURESKolmogorov complexityLogarithmSublinear functionKolmogorov structure functionChain rule for Kolmogorov complexityOpen problemInductive probabilityInductive reasoningMathematics
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Computing the Probability for Data Loss in Two-Dimensional Parity RAIDs

2017

Parity RAIDs are used to protect storage systems against disk failures. The idea is to add redundancy to the system by storing the parity of subsets of disks on extra parity disks. A simple two-dimensional scheme is the one in which the data disks are arranged in a rectangular grid, and every row and column is extended by one disk which stores the parity of it.In this paper we describe several two-dimensional parity RAIDs and analyse, for each of them, the probability for dataloss given that f random disks fail. This probability can be used to determine the overall probability using the model of Hafner and Rao. We reduce subsets of the forest counting problem to the different cases and show…

Discrete mathematicsHardware_MEMORYSTRUCTURESRAIDComputer science020206 networking & telecommunications02 engineering and technologyData lossGridElectronic mail020202 computer hardware & architecturelaw.inventionExact algorithmCounting problemlawData_FILES0202 electrical engineering electronic engineering information engineeringTutte polynomialParity (mathematics)2017 13th European Dependable Computing Conference (EDCC)
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