Search results for "Operator"
showing 10 items of 1427 documents
Existence results for parametric boundary value problems involving the mean curvature operator
2014
In this note we propose a variational approach to a parametric differential problem where a prescribed mean curvature equation is considered. In particular, without asymptotic assumptions at zero and at infinity on the potential, we obtain an explicit positive interval of parameters for which the problem under examination has at least one nontrivial and nonnegative solution.
Contemporary Ergonomics and Business 2011: Proceedings of the 1st International Scientific-Practical Conference of the Latvian Ergonomics Society (7 …
2011
All published papers are peer-reviewed.
The France’s mobile phone market faced with the entry of the 4th operator, Free
2016
At the end of 2009, the competition authorities have granted a 4th mobile license to Free, French operator already present in the fixed telephony and the Internet. The new operator not having a good coverage, he obtained permission to sign a roaming agreement with the incumbent operator Orange, enabling Free subscribers access to the network in areas not yet covered. Given its dependence on Orange, Free can be seen as a virtual mobile operator. We use a parameter that describes the level of independence of Free and can take three possible values. At first Free is an operator totally dependent on Orange. Then, a part of the traffic of Free passes by its own network. Finally, Free is an indep…
Padziļināts ieskats funkcionalanalīzes kursa dažos jēdzienos un uzdevumos
2021
Darbā aplūkoti atsevišķi funkcionālanalīzes uzdevumi un jēdzieni (skalārais reizinājums un tā īpašības, Košī nevienādība un tās vispārinājumi, operatora norma) ar mērķi kritiski salīdzināt dažādos avotos atrodamo informāciju un sniegt (studentiem) labāku izpratni par apskatāmajiem jēdzieniem un uzdevumiem.
An evolutionary approach to multi-objective scheduling of mixed model assembly lines
1999
In this paper a multi-objective genetic algorithm for the scheduling of a mixed model assembly line is proposed, pursuing the line stop time minimisation together with the component usage smoothing. Specific features of the developed GA are step by step random selection of diversified crossover and mutation operators, population control for the substitution of duplicate chromosomes, and in-process updating of GA control parameters. Three different formulation of the fitness function were been tested with some distinct line configurations.
Influence of Operator's Experience on Root Canal Shaping Ability with a Rotary Nickel-Titanium Single-File Reciprocating Motion System
2013
The aim of this study was to evaluate the influence of the operator's experience on the shaping of double-curvature simulated root canals with a nickel-titanium single-file reciprocating motion system.Sixty double-curvature root canals simulated in methacrylate blocks were prepared by 10 students without any experience in endodontics and by 10 professionals who had studied endodontics at the postgraduate level. The Reciproc-VDW system's R25 file was used in the root canal preparation. The blocks were photographed before and after the instrumentation, and the time of instrumentation was also evaluated. Changes in root canal dimensions were analyzed in 6 positions.Significant differences (P.0…
On Fourier integral operators with Hölder-continuous phase
2018
We study continuity properties in Lebesgue spaces for a class of Fourier integral operators arising in the study of the Boltzmann equation. The phase has a H\"older-type singularity at the origin. We prove boundedness in $L^1$ with a precise loss of decay depending on the H\"older exponent, and we show by counterexamples that a loss occurs even in the case of smooth phases. The results can be seen as a quantitative version of the Beurling-Helson theorem for changes of variables with a H\"older singularity at the origin. The continuity in $L^2$ is studied as well by providing sufficient conditions and relevant counterexamples. The proofs rely on techniques from Time-frequency Analysis.
Compactness of Fourier integral operators on weighted modulation spaces
2019
Using the matrix representation of Fourier integral operators with respect to a Gabor frame, we study their compactness on weighted modulation spaces. As a consequence, we recover and improve some compactness results for pseudodifferential operators.
On global solutions of the Maxwell-Dirac equations
1987
We prove, for the Maxwell-Dirac equations in 1+3 dimensions, that modified wave operators exist on a domain of small entire test functions of exponential type and that the Cauchy problem, inR+×R3, has a unique solution for each initial condition (att=0) which is in the image of the wave operator. The modification of the wave operator, which eliminates infrared divergences, is given by approximate solutions of the Hamilton-Jacobi equation, for a relativistic electron in an electromagnetic potential. The modified wave operator linearizes the Maxwell-Dirac equations to their linear part.
Operator mixing and scaling deviations in asymptotically free field theories
1976
Predictions of asymptotically free field theories for scaling deviations of the structure functions are compared with recent SLAC and Fermilab data on deep-inelastic lepton-hadron scattering. Contributions of nonsinglet as well as singlet Wilson operators are taken into account. The latter contributions are found to be non-negligible; specifically it is observed, in agreement with neutrino data, that about 60% of the proton's momentum is due to gluons. The expected quantitative pattern of scaling violations is given for a large range of ..omega.. and Q/sup 2/. (AIP)