Search results for "PLE"

showing 10 items of 22773 documents

Spin-lattice relaxation of deuterated methyl groups: Implications of the pauli principle

1999

The high-field spin-lattice relaxation of deuterated methyl groups undergoing rotational tunneling is investigated theoretically. It is found that for systems showing a tunneling frequency comparable to accessible Larmor frequencies the relaxation to equilibrium of the Zeeman energy does not follow a simple exponential time dependence even in powdered samples due to a finite coupling to the relaxation of the tunneling system. This finding contrasts to the high-temperature behavior of reorienting methyl groups which undergo simple exponential relaxation. The nonexponentiality has its origin in the statistical coupling of the three deuteron spins due to the Pauli principle.

symbols.namesakePauli exclusion principleDeuteriumCondensed matter physicsSolid-state physicsSpinsChemistrysymbolsSpin–lattice relaxationRelaxation (physics)Zeeman energyAtomic and Molecular Physics and OpticsQuantum tunnellingApplied Magnetic Resonance
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A Place for Life

2010

The belief in the existence of extraterrestrial civilizations starts from the so-called principle of mediocrity. This principle postulates that Earth is a normal planet that rotates around a normal star, which in turn is located in a normal galaxy. That is to say, there is nothing so special in our world as to make it unique. This is a logical conclusion, toward which we are guided by the successive “Copernican turns” that science has suffered throughout its long history, and which has ­removed us from the central position we once believed to occupy in the universe.

symbols.namesakePlanetNothingMediocrity principleExtraterrestrial lifePhilosophysymbolsCopernican principleLogical consequenceExoplanetEpistemology
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New Types of Jacobian-Free Approximate Riemann Solvers for Hyperbolic Systems

2017

We present recent advances in PVM (Polynomial Viscosity Matrix) methods based on internal approximations to the absolute value function. These solvers only require a bound on the maximum wave speed, so no spectral decomposition is needed. Moreover, they can be written in Jacobian-free form, in which only evaluations of the physical flux are used. This is particularly interesting when considering systems with complex Jacobians, as the relativistic magnetohydrodynamics (RMHD) equations. The proposed solvers have also been extended to the case of approximate DOT (Dumbser-Osher-Toro) methods, which can be regarded as simple and efficient approximations to the classical Osher-Solomon method. Som…

symbols.namesakePolynomialRiemann hypothesisMatrix (mathematics)Riemann problemSimple (abstract algebra)Jacobian matrix and determinantsymbolsApplied mathematicsRiemann solverMathematicsMatrix decomposition
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Partial *-Algebras of Operators in a PIP-Space

2009

The family of operators on a pip-space V is endowed with two, possibly different, partial multiplications, where partial means that the multiplication is not defined for any pair A,B of elements of Op(V) but only for certain couples. The two multiplications, to be called strong and weak, give rise to two different structures that coincide in certain situations. In this chapter we will discuss first the structure of Op(V) as partial *-algebra in the sense of [AIT02] and then the possibility of representing an abstract partial *-algebra into Op(V).

symbols.namesakePure mathematicsComplete latticeHilbert spacesymbolsStructure (category theory)MultiplicationAlgebra over a fieldSpace (mathematics)Dual pairMathematics
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COMPLEX CONVEXITY AND VECTOR-VALUED LITTLEWOOD–PALEY INEQUALITIES

2003

Let 2 p 0s uch thatfHp(X) (� f(0)� p + λ (1 −| z| 2 ) p−1 � f � (z)� p dA(z)) 1/p ,f or all f ∈ H p (X). Applications to embeddings between vector-valued BMOA spaces defined via Poisson integral or Carleson measures are provided.

symbols.namesakePure mathematicsComplex convexityLittlewood paleyGeneral MathematicsMathematical analysisPoisson kernelsymbolsMathematicsBulletin of the London Mathematical Society
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Carleson's counterexample and a scale of Lorentz-BMO spaces on the bitorus

2005

We introduce a full scale of Lorentz-BMO spaces BMO L p,q on the bidisk, and show that these spaces do not coincide for different values ofp andq. Our main tool is a detailed analysis of Carleson's construction in [C].

symbols.namesakeScale (ratio)General MathematicsLorentz transformationMathematical analysisFull scalesymbolsMathematicsCounterexample
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Stochastic linearization for the response of MDOF systems subjected to external and parametric Gaussian excitations

1991

The stochastic linearization approach is examined for the most general case of non zero-mean response of non-linear MDOF systems subjected to parametric and external Gaussian white excitations. It is shown that, for these systems too, stochastic linearization and Gaussian closure are two equivalent approaches if the former is applied to the coefficients of the Ito differential rule. Moreover, an extension of the Atalik-Utku approach to non zero-mean response systems allows to obtain simple formulations for the linearized drift coefficients. Some applications show the good accuracy of the method.

symbols.namesakeSimple (abstract algebra)Control theoryLinearizationGaussiansymbolsClosure (topology)Applied mathematicsRandom vibrationDifferential (infinitesimal)Parametric statisticsMathematics
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Computing Difficulties for Deriving Poverty Indices from Some Functional Forms of Lorenz Curves

2014

We examine three families of classical one-parameter functional forms for estimating a Lorenz curve: the power form (Pareto, elementary form), the exponential form (Gupta, elementary form) and fractional form (Rohde). For the first time, we systematically study these functions not for their ability to be estimated but on the point of view of the possibility of deriving poverty indices, which implies first determining the headcount ratio (i.e., the percentage of poor). We show that computing difficulties have been largely underestimated. Two forms, the most simple ones, pose no problem: the elementary power and exponential forms. However, the Pareto functional form poses problem with a restr…

symbols.namesakeSimple (abstract algebra)Lambert W functionLine (geometry)symbolsPareto principleApplied mathematicsLorenz curveMathematical economicsLeast squaresDomain (mathematical analysis)Exponential functionMathematicsSSRN Electronic Journal
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Self-Defence Against Non-State Actors: Impulses from the Max Planck Trialogues on the Law of Peace and War

2017

The legality of self-defence against non-state actors is currently one of the most contested issues of the jus contra bellum. How should we interpret state practice – has it already given rise, in law, to a broader concept of self-defence, or is the traditional state centred view still good law? Under which specific requirements should self-defence against non-state actors, if at all, be regarded as lawful and how can an abuse of an extended right to self-defence be prevented? The “Impulses from the Max Planck Trialogues on the Law of Peace and War” consist of short essays dealing with these questions. The essays are grouped in four categories: 1) restrictivist positions upholding a state-c…

symbols.namesakeState (polity)media_common.quotation_subjectLawPolitical sciencesymbolsPrinciple of legalityPlanckSelf defenseExpansivemedia_commonSSRN Electronic Journal
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Sympathetic nervous system synchrony between participants of couple therapy

2017

Synchrony, or the moment-by-moment coordination between people in social situations, has been connected with increased liking and rapport. However, this type of synchrony is an underexplored area with regard to autonomic nervous system activity. The purpose of this research was to study physiological synchrony between participants in couple therapy by focusing on the sympathetic nervous system (SNS), which reflects arousal and emotional reactions. The data comprised 12 couple therapy cases (24 clients, 10 therapists) participating in the Relational Mind in Events of Change in Multiactor Therapeutic Dialogues (2013-2016) research project. Electrodermal activity (EDA) and heart rate were reco…

sympathetic nervous systemconcordancesykevuorovaikutussynkroniacouple therapytherapeutic alliancetherapy outcomeautonomic nervous systemtuloksellisuusphysiological synchronyelectrodermal activitycoherencehoitosuhdeautonominen hermostoelektrofysiologiapariterapiainterpersonal physiologylinkagefysiologiset vaikutukset
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