Search results for " Operator"
showing 10 items of 931 documents
Il Management in sala operatoria: l'esperienza dell'A.O.U.P. "Paolo Giaccone" -palermo
2006
Continuous spectrum for a two phase eigenvalue problem with an indefinite and unbounded potential
2020
Abstract We consider a two phase eigenvalue problem driven by the ( p , q ) -Laplacian plus an indefinite and unbounded potential, and Robin boundary condition. Using a modification of the Nehari manifold method, we show that there exists a nontrivial open interval I ⊆ R such that every λ ∈ I is an eigenvalue with positive eigenfunctions. When we impose additional regularity conditions on the potential function and the boundary coefficient, we show that we have smooth eigenfunctions.
Il maschile e il femminile. Una riflessione sulla radice di senso dell'identità di genere
2014
Il tema del maschile e del femminile e il senso della loro reciprocità è percepito come problematico in una cultura come quella attuale, segnata da una propensione all’indifferenziazione sessuale. La questione, per l’elaborazione di un’antropologia pedagogica della sponsalità e della paternità/maternità, è nodale. Il saggio propone una riflessione di stile fenomenologico, volta a ritrovare la radice di senso delle categorie di maschilità e di femminilità, ritrovandole nell’aspetto per cui esso si mostrano costitutive dell’esistenza personale. Tale senso originario resta sempre presente in ogni ricerca e in ogni momento della costruzione della propria singolare identità di genere.
Influence of greenhouse different coverings on chemical and physical risk factors
2005
Crop production in greenhouses needs the use of chemicals and requires high levels of temperature and relative humidity to assure the increasing of crop production. This can cause risks for the health of the operators, especially if they are not equipped with protection devices. The risks may also vary with the type and/or size and/or shape of the protected structures. In order to determine the influence of different coverings on type and amount of risks, chemical and physical risk factors were measured inside greenhouses with different cladding materials (glass panels and plastic films) after crop management. In these two different greenhouses typologies, that were similar for location and…
Toward a formalization of a two traders market with information exchange
2014
This paper shows that Hamiltonians and operators can also be put to good use even in contexts which are not purely physics based. Consider the world of finance. The work presented here {models a two traders system with information exchange with the help of four fundamental operators: cash and share operators; a portfolio operator and an operator reflecting the loss of information. An information Hamiltonian is considered and an additional Hamiltonian is presented which reflects the dynamics of selling/buying shares between traders. An important result of the paper is that when the information Hamiltonian is zero, portfolio operators commute with the Hamiltonian and this suggests that the dy…
Stability Analysis and Stabilization of T-S Fuzzy Delta Operator Systems with Time-Varying Delay via an Input-Output Approach
2013
Published version of an article in the journal: Mathematical Problems in Engineering. Also available from the publisher at: http://dx.doi.org/10.1155/2013/913234 Open Access The stability analysis and stabilization of Takagi-Sugeno (T-S) fuzzy delta operator systems with time-varying delay are investigated via an input-output approach. A model transformation method is employed to approximate the time-varying delay. The original system is transformed into a feedback interconnection form which has a forward subsystem with constant delays and a feedback one with uncertainties. By applying the scaled small gain (SSG) theorem to deal with this new system, and based on a Lyapunov Krasovskii funct…
Mapping properties of weakly singular periodic volume potentials in Roumieu classes
2020
The analysis of the dependence of integral operators on perturbations plays an important role in the study of inverse problems and of perturbed boundary value problems. In this paper, we focus on the mapping properties of the volume potentials with weakly singular periodic kernels. Our main result is to prove that the map which takes a density function and a periodic kernel to a (suitable restriction of the) volume potential is bilinear and continuous with values in a Roumieu class of analytic functions. This result extends to the periodic case of some previous results obtained by the authors for nonperiodic potentials, and it is motivated by the study of perturbation problems for the solut…
Evaluation of Internet channels and their impacts on Irish mobile operators' business models
2013
Ademowo, Adewale Adebayo Evaluation of Internet Channels and their impacts on Irish Mobile Operators' Business Models Jyväskylä: University of Jyväskylä, 2013, 108 p. Mobile Technology and Business (Major in Information Systems Science), Master's Thesis Supervisor: Luoma, Eetu This study finds the impacts of the Internet channels on mobile operators’ business models with Ireland as a case. It reflects on the business model concepts, business models of mobile telecom industry and specifically Irish mobile operators; and evaluates and highlights the impacts of the internet channels used by the operators. This study uses exploratory case study as a methodology and qualitative method as an appr…
Variations on Weyl's theorem
2006
AbstractIn this note we study the property (w), a variant of Weyl's theorem introduced by Rakočević, by means of the localized single-valued extension property (SVEP). We establish for a bounded linear operator defined on a Banach space several sufficient and necessary conditions for which property (w) holds. We also relate this property with Weyl's theorem and with another variant of it, a-Weyl's theorem. We show that Weyl's theorem, a-Weyl's theorem and property (w) for T (respectively T*) coincide whenever T* (respectively T) satisfies SVEP. As a consequence of these results, we obtain that several classes of commonly considered operators have property (w).
The Hermitian part of a Rickart involution ring, I
2014
Rickart *-rings may be considered as a certain abstraction of the rings B(H) of bounded linear operators of a Hilbert space H. In 2006, S. Gudder introduced and studied a certain ordering (called the logical order) of self-adjoint Hilbert space operators; the set S(H) of these operators, which is a partial ring, may be called the Hermitian part of B(H). The new order has been further investigated also by other authors. In this first part of the paper, an abstract analogue of the logical order is studied on certain partial rings that approximate the Hermitian part of general *-rings; the special case of Rickart *-rings is postponed to the next part.