Search results for "Computation"

showing 10 items of 7362 documents

1H and 13C shielding measurements in comparison with DFT calculations performed for two 2-(acetyloamino)-N,N-dimethyl-3-phenylacrylamide isomers

2015

Abstract We present measurements of 1H and 13C shielding for (2E)- and (2Z)-2-(acetyloamino)-N,N-dimethyl-3-phenylacrylamide isomers in solutions. Practically the same values of the shielding were obtained using internal and external referencing. For the interpretation, we explore DFT calculations of shieldings performed at the rovibrationally averaged geometries. The comparison of the experimental and theoretical results is verified both for the shielding and chemical shift. It appears that some inaccuracies in the calculations of the chemical shift can be reduced due to the error compensation while subtracting the reference shielding. As shown the measurement of magnetic shielding can be …

Theoretical physicsMaterials scienceElectromagnetic shieldingGeneral Physics and AstronomyPhysical and Theoretical ChemistryComputational physicsInterpretation (model theory)Compensation (engineering)Chemical Physics Letters
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New QM/MM implementation of the DFTB3 method in the gromacs package.

2015

The approximate density-functional tight-binding theory method DFTB3 has been implemented in the quantum mechanics/molecular mechanics (QM/MM) framework of the Gromacs molecular simulation package. We show that the efficient smooth particle–mesh Ewald implementation of Gromacs extends to the calculation of QM/MM electrostatic interactions. Further, we make use of the various free-energy functionalities provided by Gromacs and the PLUMED plugin. We exploit the versatility and performance of the current framework in three typical applications of QM/MM methods to solve biophysical problems: (i) ultrafast proton transfer in malonaldehyde, (ii) conformation of the alanine dipeptide, and (iii) el…

Theory methodComputer scienceMolecular simulationGeneral ChemistryExtended samplingFree energy simulationMolecular dynamicsDensity-functional tight-bindingComputational scienceQM/MMComputational MathematicsMolecular dynamicsQuantum TheoryThermodynamicsComputer Simulationta116Quantum mechanics/molecular mechanicsSoftwareProtein BindingJournal of computational chemistry
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Oxygen isotope composition of North American bobcat (Lynx rufus) and puma (Puma concolor) bone phosphate: implications for provenance and climate rec…

2015

Feline carnivores are threatened by illegal wildlife trade. Tracing the provenance of unknown felid tissues via stable isotope analysis could provide important information in wildlife crime investigations. The oxygen isotope composition of mammalian skeletal phosphate (δ18Op) is widely applied to trace the origin of animal remains and to reconstruct migratory patterns in palaeontological, archaeological, ecological and wildlife forensic applications. Teeth and bones of terrestrial mammals form at constant body temperature in isotope equilibrium with body water, which is predominantly controlled by ingested meteoric water (δ18Ow) that varies systematically with latitude, altitude and climate…

TheoryofComputation_ANALYSISOFALGORITHMSANDPROBLEMCOMPLEXITY
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Descriptional and Computational Complexity of the Circuit Representation of Finite Automata

2018

In this paper we continue to investigate the complexity of the circuit representation of DFA—BC-complexity. We compare it with nondeterministic state complexity, obtain upper and lower bounds which differ only by a factor of 4 for a Binary input alphabet. Also we prove that many simple operations (determining if a state is reachable or if an automaton is minimal) are PSPACE-complete for DFA given in circuit representation.

TheoryofComputation_COMPUTATIONBYABSTRACTDEVICESFinite-state machineTheoretical computer scienceComputational complexity theoryComputer science020208 electrical & electronic engineering020206 networking & telecommunications02 engineering and technologyUpper and lower boundsAutomatonNondeterministic algorithmTheoryofComputation_MATHEMATICALLOGICANDFORMALLANGUAGESSimple (abstract algebra)0202 electrical engineering electronic engineering information engineeringState (computer science)Representation (mathematics)Computer Science::Formal Languages and Automata Theory
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An Approximate Determinization Algorithm for Weighted Finite-State Automata

2001

Nondeterministic weighted finite-state automata are a key abstraction in automatic speech recognition systems. The efficiency of automatic speech recognition depends directly on the sizes of these automata and the degree of nondeterminism present, so recent research has studied ways to determinize and minimize them, using analogues of classical automata determinization and minimization. Although, as we describe here, determinization can in the worst case cause poly-exponential blowup in the number of states of a weighted finite-state automaton, in practice it is remarkably successful. In extensive experiments in automatic speech recognition systems, deterministic weighted finite-state autom…

TheoryofComputation_COMPUTATIONBYABSTRACTDEVICESFinite-state machineTheoretical computer scienceGeneral Computer ScienceComputer scienceApplied MathematicsComputer Science ApplicationsAutomatonNondeterministic algorithmNondeterministic finite automaton with ε-movesComputer Science::SoundDeterministic automatonTheory of computationStandard testMinificationAlgorithmComputer Science::Formal Languages and Automata TheoryAlgorithmica
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Supplementary tables from Antibiotics accelerate growth at the expense of immunity

2021

This file contains the enrichment, annotation, a list of pathogenic bacteria, the primer sequences, and life-history data

TheoryofComputation_COMPUTATIONBYABSTRACTDEVICESGeneralLiterature_REFERENCE(e.g.dictionariesencyclopediasglossaries)
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Quantum versus Probabilistic One-Way Finite Automata with Counter

2001

The paper adds the one-counter one-way finite automaton [6] to the list of classical computing devices having quantum counterparts more powerful in some cases. Specifically, two languages are considered, the first is not recognizable by deterministic one-counter one-way finite automata, the second is not recognizable with bounded error by probabilistic one-counter one-way finite automata, but each recognizable with bounded error by a quantum one-counter one-way finite automaton. This result contrasts the case of one-way finite automata without counter, where it is known [5] that the quantum device is actually less powerful than its classical counterpart.

TheoryofComputation_COMPUTATIONBYABSTRACTDEVICESNested wordComputer scienceTimed automatonBüchi automatonω-automatonNondeterministic finite automaton with ε-movesTuring machinesymbols.namesakeDFA minimizationDeterministic automatonContinuous spatial automatonQuantum finite automataDeterministic system (philosophy)Two-way deterministic finite automatonNondeterministic finite automatonDiscrete mathematicsFinite-state machineQuantum dot cellular automatonNonlinear Sciences::Cellular Automata and Lattice GasesMobile automatonTheoryofComputation_MATHEMATICALLOGICANDFORMALLANGUAGESDeterministic finite automatonProbabilistic automatonsymbolsAutomata theoryComputer Science::Formal Languages and Automata TheoryQuantum cellular automaton
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Multiple Usage of Random Bits in Finite Automata

2012

Finite automata with random bits written on a separate 2-way readable tape can recognize languages not recognizable by probabilistic finite automata. This shows that repeated reading of random bits by finite automata can have big advantages over one-time reading of random bits.

TheoryofComputation_COMPUTATIONBYABSTRACTDEVICESNested wordFinite-state machineTheoretical computer scienceKolmogorov complexityComputer scienceω-automatonNonlinear Sciences::Cellular Automata and Lattice GasesBit fieldTuring machinesymbols.namesakeTheoryofComputation_MATHEMATICALLOGICANDFORMALLANGUAGESsymbolsQuantum finite automataAutomata theoryArithmeticComputer Science::DatabasesComputer Science::Formal Languages and Automata Theory
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Tally languages accepted by Monte Carlo pushdown automata

1997

Rather often difficult (and sometimes even undecidable) problems become easily decidable for tally languages, i.e. for languages in a single-letter alphabet. For instance, the class of languages recognizable by 1-way nondeterministic pushdown automata equals the class of the context-free languages, but the class of the tally languages recognizable by 1-way nondeterministic pushdown automata, contains only regular languages [LP81]. We prove that languages over one-letter alphabet accepted by randomized one-way 1-tape Monte Carlo pushdown automata are regular. However Monte Carlo pushdown automata can be much more concise than deterministic 1-way finite state automata.

TheoryofComputation_COMPUTATIONBYABSTRACTDEVICESNested wordTheoretical computer scienceComputational complexity theoryComputer scienceDeterministic pushdown automatonTuring machinesymbols.namesakeRegular languageComputer Science::Logic in Computer ScienceQuantum finite automataNondeterministic finite automatonDiscrete mathematicsFinite-state machineDeterministic context-free languageComputabilityDeterministic context-free grammarContext-free languagePushdown automatonAbstract family of languagesComputer Science::Computation and Language (Computational Linguistics and Natural Language and Speech Processing)Cone (formal languages)Embedded pushdown automatonUndecidable problemNondeterministic algorithmTheoryofComputation_MATHEMATICALLOGICANDFORMALLANGUAGESDeterministic finite automatonsymbolsComputer Science::Programming LanguagesAlphabetComputer Science::Formal Languages and Automata Theory
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Local automata and completion

1993

The problem of completing a finite automata preserving its properties is here investigated in the case of deterministic local automata. We show a decision procedure and give an algorithm which complete a deterministic local automaton (if the completion exists) with another one, having the same number of states.

TheoryofComputation_COMPUTATIONBYABSTRACTDEVICESNested wordTheoretical computer scienceComputer scienceTimed automatonω-automatonNonlinear Sciences::Cellular Automata and Lattice GasesTheoryofComputation_MATHEMATICALLOGICANDFORMALLANGUAGESDeterministic finite automatonDFA minimizationAutomata theoryQuantum finite automataNondeterministic finite automatonComputer Science::Formal Languages and Automata Theory
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