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Matematică și Fizică Aplicate

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Din 1929

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PARAMETRIC ESTIMATION OF CONDITIONAL COPULAS

person Mariana Craiu
Copulas have evolved into a popular tool for modeling dependence in a large number of statistical models.Generally, a copula establishes a flexible bridge between marginal distributions ,thus allowing various dependent models to be created.Recently ,an extension of the classical copula...

GAMMA-RINGS: SOME INTERPRETATIONS USED IN THE STUDY OF THEIR RADICALS

person Mariana DUMITRU
We study some concepts of gamma-rings and ternary rings, inspired by the study of rectangular matrices over fields. We point out some of their properties which are necessary for defining radicals for such algebraic structures and getting structure theorems. Some connections between maximal...

RANDOM SOLUTIONS OF FUNCTIONAL DIFFERENTIAL INCLUSIONS OF NEUTRAL TYPE

person Carmina GEORGESCU
This paper is devoted to the study of neutral functional differential inclusions defined on a separable Banach space and depending in a measurable way on a random parameter. We first prove an existence result for a class of neutral functional differential inclusions with memory. Then we...

SOME APPLICATIONS OF THE HILBERT TRANSFORM

person ªtefania Constantinescu
In this paper we recall some properties of the Hilbert transform interpreted in terms of the mathematical theory of the random signals. We study the representation of the analitical signals as a generalization of the complex form of the sinusoidal signals, a special part being focused on the...

YETTER-DRINFELD MODULES AND GALOIS EXTENSIONS

person Adriana BALAN
In this paper we define Yetter-Drinfeld modules over a coquasi-bialgebra and prove that the category of Yetter.Drinfeld modules is monoidal, pre.braided and coincides with the left weak center of the comodule category. In particular, given a Galois extension over a coquasi-Hopf algebra, the...

ON EFFICIENCY CONDITIONS FOR NEW CONSTRAINED MINIMUM PROBLEM

person Ariana PITEA
Consider the problem (MP) of minimizing a vector of functionals of curvilinear integrals subject to PDE and/or PDI constraints. In two previous papers [5], [6], we studied efficiency necessary conditions for the problem (MP) and we introduced a new type of duality. The aim of this work is to...

AN ALTERNATIVE AND UNITED PROOF OF A DOUBLE INEQUALITY FOR BOUNDING THE ARITHMETIC-GEOMETRIC MEAN

person Feng Qi, Anthony Sofo
In the paper, we provide an alternative and united proof of a double inequality for bounding the arithmetic-geometric mean. Moreover we prove that the bounding constants of the double inequality are the best possible.

ENTANGLED QUANTUM STATES, QUANTUM TELEPORTATION AND QUANTUM INFORMATION

person Constantin P. Cristescu, Marcel Popescu
The paper presents the essentials concerning the quantum entangled states as a fundamental resource for quantum informatics. The treatment roughly follows the debate of over 70 years generated by the Einstein, Podolsky, Rosen paper formulating what was later called “the EPR paradox”,...

RELATIVISTIC RESULTS OBTAINED BY CLASSICAL ARGUMENTS

person Alexandru LUPAªCU
We present the problem of reflection at a moving surface and show that relativistic results may be deduced from simple non-relativistic computations. The variations of the frequency of the reflected wave and of the reflected angle are studied as functions of the incident angle and of the...

COMPARISON BETWEEN THE CHARACTERISTICS OF DISSOLVED ORGANIC MATTER AND NITRATE CONTENT IN AN URBAN RIVER

person Elfrida M. CARSTEA, Gabriela PAVELESCU, Luminita CRISTESCU, Andy BAKER, Dan SAVASTRU
Aquatic organic matter is constantly changing its characteristics under the interaction with different components which enter the water body through soil leaching, surface runoff or pollution. Complex processes also lead to the formation of nitrate. In order to determine the quantity of nitrate...

HEAVY IONS STRAGGLING IN BIOLOGICAL MATTER

person Ligia STRASSER, Gheorghe CATA-DANIL
In the present work it is performed a systematic study of the lateral and longitudinal stragglings occuring in the slowing down of 12C, 16O and 19F ions in materials of interest for radiotherapy. The incident energy of the ion beams considered in the present work were selected in order to ensure...

THE METROLOGY OF OPTICAL FIBRE LOSSES

person Sorin GHINOIU, Niculae N. PUªCAª
Based on the measurement of the propagation losses, optical insertion and return losses of optical fibers using nondestructive methods several experimental results are presented and analysed from metrology point of view in this paper.\r\nUsing the Optical Transmission Method the attenuation of...

STUDY OF THE SOLIDIFICATION PROCESS FOR METAL FLUIDS IN A DYNAMIC FIELD

person Liviu Andronovici
The this study presents the posibility of new technique applied to fluid metals and their crystalline structure under the effect of the energetic field of the pyramid. \r\nthere are two significant methods used to demonstrate the existence of the pyramid’s energetic field: 1-measurement...

REVERSIBILITY AND IRREVERSIBILITY IN PHYSICAL SYSTEMS

person Mircea STAN
This paper deals with a systematic approach to the study of temporal reversibility and irreversibility in physical systems. Using a simple formalism, several physical quantities and kinetic laws are then checked in some domains (classical and quantum mechanics, electrodynamics, et al.) through...