Search results for " Linear"

showing 10 items of 643 documents

Probabilistic response of linear structures equipped with nonlinear dampers devices (PIS method)

2008

Passive control introducing energy absorbing devices into the structure has received considerable attention in recent years. Unfortunately the constitutive law of viscous fluid dampers is highly nonlinear, and even supposing that the structure behaves linearly, the whole system has inherent nonlinear properties. Usually the analysis is performed by a stochastic linearization technique (SLT) determining a linear system equivalent to the nonlinear one, in a statistical sense. In this paper the effect of the non-Gaussianity of the response due to the inherent nonlinearity of the damper device will be studied in detail via the Path Integral Solution (PIS) method. A systematic study is conducted…

Short-time Gaussian approximationStochastic linearization techniqueViscous damperNonlinear systemSettore ICAR/08 - Scienza Delle CostruzioniPath integral solution
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Supramolecular polymerization of electronically complementary linear motifs: anti-cooperativity by attenuated growth†

2021

Anti-cooperative supramolecular polymerization by attenuated growth exhibited by self-assembling units of two electron-donor benzo[1,2-b:4,5-b′]dithiophene (BDT) derivatives (compounds 1a and 1b) and the electron-acceptor 4,4-difluoro-4-bora-3a,4a-diaza-s-indacene (BODIPY) (compound 2) is reported. Despite the apparent cooperative mechanism of 1 and 2, AFM imaging and SAXS measurements reveal the formation of small aggregates that suggest the operation of an anti-cooperative mechanism strongly conditioned by an attenuated growth. In this mechanism, the formation of the nuclei is favoured over the subsequent addition of monomeric units to the aggregate, which finally results in short aggrega…

Small-angle X-ray scatteringAtomic force microscopySupramolecular chemistryCooperativityGeneral Chemistrymacromolecular substanceschemistry.chemical_compoundCrystallographyChemistryMonomerchemistryPolymerizationShort linear motifBODIPYChemical Science
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Influence of environmental factors on the spatial distribution and diversity of forest soil in Latvia

2012

This study was carried out to determine the spatial relationships between environmental factors (Quaternary deposits, topographical situation, land cover, forest site types, tree species, soil texture) and soil groups, and their prefix qualifiers (according to the international Food and Agricultural Organization soil classification system World Reference Base for Soil Resources [FAO WRB]). The results show that it is possible to establish relationships between the distribution of environmental factors and soil groups by applying the generalized linear models in data statistical analysis, using the R 2.11.1 software for processing data from 113 sampling plots throughout the forest terri…

Soil mapRegosolforest typeSoil textureEcologylcsh:QE1-996.5Soil classificationLand coverlcsh:GeologyGeographySoil seriesgeneralized linear models.Unified Soil Classification SystemWorld Reference Base for Soil ResourcesGeneral Earth and Planetary SciencesPhysical geographyQuaternary depositsFAO WRB classificationWater Science and TechnologyEstonian Journal of Earth Sciences
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Multiple linear regression analysis of RF values of chlorinated catechols and guaiacols

1981

The multiple linear regression analysis of the RF values of chlorinated catechols and guaiacols has been carried out. The resolved terms, in the regression equation have been used to explain the relative mobility of chlorinated compounds to the reference compound (catechol or guaiacol). The best correlations have been observed for solvent systems which give the greatest standard deviations and relative differences between the RF values. A good correlation between the standard deviation of the RF values and the term which represents the effect of the chlorine atom ortho to the hydroxyl group(s) have also been observed.

Solvent systemCatecholOrganic ChemistryClinical BiochemistryChlorine atomAnalytical chemistryRegression analysisBiochemistryStandard deviationAnalytical Chemistrychemistry.chemical_compoundchemistrypolycyclic compoundsMultiple linear regression analysisGuaiacolChromatographia
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D-stability for discrete-time t-s fuzzy descriptor systems with multiple delays

2014

In this work, the D-stability problem is considered for a class of discrete-time Takagi-Sugeno (T-S) fuzzy descriptor systems with multiple state delays. In terms of linear matrix inequality, sufficient conditions are proposed to ensure that all poles of the descriptor T-S fuzzy system are located within a disk contained in the unit circle. Moreover, a sufficient condition is presented such that the singular system is regular, causal and D-stable in spite of multiple state delays. Finally, an example is given to show the effectiveness and advantages of the proposed techniques Refereed/Peer-reviewed

Stability of linear systemsDescriptor systemsFuzzy systemsFuzzy control systemstability of linear systemsFuzzy logicDelay systems; Fuzzy systems; Stability of linear systems; Electrical and Electronic EngineeringDiscrete time and continuous timeControl theoryfuzzy systemsFuzzy numberFuzzy associative matrixElectrical and Electronic EngineeringAlgorithmdealy systemsD stabilityDelay systemsMathematics2014 American Control Conference
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Noise-enhanced stability of periodically driven metastable states

2000

We study the effect of noise-enhanced stability of periodically driven metastable states in a system described by piecewise linear potential. We find that the growing of the average escape time with the intensity of the noise is depending on the initial condition of the system. We analytically obtain the condition for the noise enhanced stability effect and verify it by numerical simulations.

Statistical Mechanics (cond-mat.stat-mech)FOS: Physical sciencesMechanicsDisordered Systems and Neural Networks (cond-mat.dis-nn)Condensed Matter - Disordered Systems and Neural NetworksStability (probability)Piecewise linear functionControl theoryMetastabilityInitial value problemNoise (radio)Intensity (heat transfer)Condensed Matter - Statistical MechanicsMathematics
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Interval estimation for the breakpoint in segmented regression: a smoothed score-based approach

2017

Summary This paper is concerned with interval estimation for the breakpoint parameter in segmented regression. We present score-type confidence intervals derived from the score statistic itself and from the recently proposed gradient statistic. Due to lack of regularity conditions of the score, non-smoothness and non-monotonicity, naive application of the score-based statistics is unfeasible and we propose to exploit the smoothed score obtained via induced smoothing. We compare our proposals with the traditional methods based on the Wald and the likelihood ratio statistics via simulations and an analysis of a real dataset: results show that the smoothed score-like statistics perform in prac…

Statistics and Probability010504 meteorology & atmospheric sciencesInterval estimationBreakpointinduced smoothingScore01 natural sciencesConfidence intervalchangepoint010104 statistics & probabilitypiecewise linear relationshipconfidence intervalscore inferenceStatistics0101 mathematicsStatistics Probability and UncertaintySegmented regressionSettore SECS-S/01 - StatisticaStatisticSmoothing0105 earth and related environmental sciencesMathematicsAustralian & New Zealand Journal of Statistics
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The geography of Spanish bank branches

2014

This article analyzes the determinants of bank branch location in Spain taking the role of geography explicitly into account. After a long period of intense territorial expansion, especially by savings banks, many of these firms are now involved in merger processes triggered off by the financial crisis, most of which entail the closing of many branches. However, given the contributions of this type of banks to limit financial exclusion, this process might exacerbate the consequences of the crisis for some disadvantaged social groups. Related problems such as new banking regulation initiatives (Basel III), or the current excess capacity in the sector add further relevance to this problem. We…

Statistics and ProbabilityActuarial sciencemunicipalityFinancial economicsProcess (engineering)bankBayesian statisticsbranchR1Basel IIIGeneralized linear mixed modelDisadvantagedSocial groupFinancial crisisRelevance (law)Capacity utilizationG21Statistics Probability and UncertaintyC11Journal of Applied Statistics
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A Bayesian analysis of classical hypothesis testing

1980

The procedure of maximizing the missing information is applied to derive reference posterior probabilities for null hypotheses. The results shed further light on Lindley’s paradox and suggest that a Bayesian interpretation of classical hypothesis testing is possible by providing a one-to-one approximate relationship between significance levels and posterior probabilities.

Statistics and ProbabilityBayes factorBayesian inferenceStatistics::ComputationBayesian statisticsStatisticsEconometricsBayesian experimental designStatistics::MethodologyStatistics Probability and UncertaintyBayesian linear regressionLindley's paradoxBayesian averageMathematicsStatistical hypothesis testingTrabajos de Estadistica Y de Investigacion Operativa
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What Bayesians Expect of Each Other

1991

Abstract Our goal is to study general properties of one Bayesian's subjective beliefs about the behavior of another Bayesian's subjective beliefs. We consider two Bayesians, A and B, who have different subjective distributions for a parameter θ, and study Bayesian A's expectation of Bayesian B's posterior distribution for θ given some data Y. We show that when θ can take only two values, Bayesian A always expects Bayesian B's posterior distribution to lie between the prior distributions of A and B. Conditions are given under which a similar result holds for an arbitrary real-valued parameter θ. For a vector parameter θ we present useful expressions for the mean vector and covariance matrix …

Statistics and ProbabilityBayesian probabilityPosterior probabilityBayesian inferenceStatistics::ComputationBayesian statisticsStatisticsBayesian experimental designBayesian hierarchical modelingApplied mathematicsStatistics Probability and UncertaintyBayesian linear regressionBayesian averageMathematicsJournal of the American Statistical Association
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