1 MB - http://www.iaea.org/inis/collection/NCLCollectionStore/_Public/44/096/44096828.pdf - Text Version by Esmail, S.F.H. (Nuclear Research Center, Egyptian Atomic Energy Authority, Cairo (Egypt)); Zagazig University , Department of Mathematics (Egypt) Read MoreCollapse

[en]

The mathematical formulation of numerous physical problems a results in differential
equations actually partial or ordinary differential equations.In our study we are
interested in solutions of partial differential equations.The aim of this work is
to calculate the concentrations of the pollution, by solving the atmospheric diffusion
equation(ADE) using different mathematical methods of solution. It is difficult to
solve the general form of ADE analytically, so we use some assumptions to get its
solution.The solutions of it depend on the eddy diffusivity profiles(k) and the wind
speed u. We use some physical assumptions to simplify its formula and solve it. In
the present work, we solve the ADE analytically in three dimensions using Green's
function method, Laplace transform method, normal mode method and these separation
of variables method. Also, we use ADM as a numerical method. Finally, comparisons
are made with the results predicted by the previous methods and the observed data.$$$$

http://dx.doi.org/10.1070/SM2014v205n10ABEH004425by Osipenko, K Yu (Moscow State Aviation Technological University, Moscow (Russian Federation)) Read MoreCollapse

[en]

The paper looks at problems concerning the recovery of operators from noisy information
in non-Euclidean metrics. A number of general theorems are proved and applied
to recovery problems for functions and their derivatives from the noisy Fourier transform.
In some cases, a family of optimal methods is found, from which the methods requiring
the least amount of original information are singled out. Bibliography: 25 titles$$$$

141 KB - http://www.iaea.org/inis/collection/NCLCollectionStore/_Public/43/106/43106915.pdf - Text Version by International Atomic Energy Agency, International Nuclear Data Committee, Vienna (Austria) Read MoreCollapse

[en]

Reports are on: - Measurement of Cross-Sections for Neutron Induced Reactions at 14
MeV. - Level Schemes and Gamma Ray Angular Distribution Measurements in ^{28}Si,
^{46}Ti, and ^{53}Mn. - A Study of Neutron-Induced Reaction ''1''2C
(n.n')3α at E_{n} =17.4 MeV. - A Study on Nuclear Evaporation in Nuclear Emulsion
Exposed to 3.0 GeV/c Mesons. - Spectroscopy of ^{64}Cu using the (^{3}He,p)
Reaction at 18 MeV.$$$$

We present an evolutionary computational approach for the solution of nonlinear ordinary
differential equations (NLODEs). The mathematical modeling is performed by a feed-forward
artificial neural network that defines an unsupervised error. The training of these
networks is achieved by a hybrid intelligent algorithm, a combination of global search
with genetic algorithm and local search by pattern search technique. The applicability
of this approach ranges from single order NLODEs, to systems of coupled differential
equations. We illustrate the method by solving a variety of model problems and present
comparisons with solutions obtained by exact methods and classical numerical methods.
The solution is provided on a continuous finite time interval unlike the other numerical
techniques with comparable accuracy. With the advent of neuroprocessors and digital
signal processors the method becomes particularly interesting due to the expected
essential gains in the execution speed. (authors)$$$$

http://dx.doi.org/10.1070/SM2014v205n02ABEH004373by Nikolaenko, S S (M. V. Lomonosov Moscow State University, Faculty of Mechanics and Mathematics,
Moscow (Russian Federation)) Read MoreCollapse

[en]

The paper is concerned with the topological analysis of the Chaplygin integrable case
in the dynamics of a rigid body in a fluid. A full list of the topological
types of Chaplygin systems in their dependence on the energy level is compiled on
the basis of the Fomenko-Zieschang theory. An effective description of the topology
of the Liouville foliation in terms of natural coordinate variables is also presented,
which opens a direct way to calculating topological invariants. It turns out
that on all nonsingular energy levels Chaplygin systems are Liouville equivalent to
the well-known Euler case in the dynamics of a rigid body with fixed point. Bibliography:
23 titles$$$$

11 MB - http://www.iaea.org/inis/collection/NCLCollectionStore/_Public/46/034/46034786.pdf - Text Version by Brisbois, Jacques; Commissariat a l'Energie Atomique - CEA, Centre d'Etudes Nucleaires de Fontenay-aux-Roses,
Direction des Piles Atomiques, Departement des Etudes de Piles, Service d'Etudes de
Protections de Piles (France) Read MoreCollapse

[en]

Protection issues are problems related to the presence of neutron and gamma radiations:
biological dose, material heating, Wigner effect, gas ionization. The objective is
then to determine the biological doses which are predictable in some reactor areas,
and to assess the effects of irradiation on materials during the reactor lifetime.
For these purposes, problems of particle propagation are addressed, and the effects
of radiations related to one phenomenon or another are studied with respect to radiation
energy. The author first describes methods used to compute general propagation. These
are mainly codes using Monte Carlo or multi-group scattering methods. These methods
are experimentally controlled on a sub-critical graphite-natural uranium set. In a
second part, the author presents the different radiation sources which are to be taken
into account in calculations. Then he indicates the nuclear constants to be used in
the different codes, as well as the response functions to be used to calculate a specific
phenomenon (steel, graphite Wigner effect, so on) from the particle spectrum. In the
fourth part, the author describes the different methods which can be used to solve
problems which are specific to graphite reactors. In the last part, obtained calculated
results are compared with experimental measurements performed on power reactors$$$$

[fr]

Il convient avant
tout de definir ce que l'on entend par problemes de protection. Nous appelerons problemes
de protection, les problemes lies a la presence de neutrons et de gamma, tels que
dose biologique, echauffement des materiaux, effet Wigner, ionisation des gaz. Le
but principal des etudes est de determiner les doses biologiques previsibles en certains
points du reacteur, en marche ou a l'arret, ce qui peut conduire d'ailleurs a proposer
des modifications des structures permettant d'atteindre les conditions de dose recherchees.
Mais c'est aussi de fournir aux technologues les renseignements necessaires pour qu'ils
puissent evaluer les effets des rayonnements sur les materiaux pendant la duree de
vie du reacteur. Pour atteindre ce but, on est amene d'une part a traiter des problemes
de propagation de particules et d'autre part a etudier les effets des rayonnements
relatifs a tel ou tel phenomene, en fonction de leur energie. Le premier chapitre
est consacre a la description de methodes de calcul de propagation a caractere general.
Ce sont essentiellement des codes de calcul sur IBM 360 utilisant des methodes de
Monte Carlo ou de diffusion multigroupes. Ces methodes ont ete verifiees experimentalement
sur le dispositif NAIADE II, qui est un ensemble sous-critique graphite-uranium naturel.
Nous presentons au 2e chapitre les sources de rayonnement a prendre en compte dans
les calculs. Au chapitre 3, nous donnons les constantes nucleaires a utiliser dans
les differents codes, ainsi que les fonctions de reponse a utiliser pour calculer
un phenomene particulier (effet Wigner graphite, acier...) a partir du spectre de
particules. Dans le chapitre 4, nous decrivons les differentes methodes qui peuvent
etre utilisees pour resoudre les problemes specifiques des piles a graphite. Enfin
au chapitre 5, nous comparons les resultats obtenus par ces methodes aux mesures effectuees
sur les reacteurs de puissance. (auteur)

300 KB - http://www.iaea.org/inis/collection/NCLCollectionStore/_Public/47/006/47006391.pdf - Text Version by Nicolau, Andressa dos Santos; Schirru, Roberto (Coordenacao dos Programas de Pos-Graduacao em Engenharia (COPPE/UFRJ), Rio de Janeiro,
RJ (Brazil). Programa de Engenharia Nuclear), E-mail: andressa@lmp.ufrj.br; Associacao Brasileira de Energia Nuclear (ABEN), Rio de Janeiro, RJ (Brazil) Read MoreCollapse

[en]

Recently quantum-inspired version of the Particle Swarm Optimization (PSO) algorithm,
Quantum Particle Swarm Optimization (QPSO) was proposed. The QPSO algorithm permits
all particles to have a quantum behavior, where some sort of 'quantum motion'
is imposed in the search process. When the QPSO is tested against a set of benchmarking
functions, it showed superior performances as compared to classical PSO. The QPSO
outperforms the classical one most of the time in convergence speed and achieves better
levels for the fitness functions. The great advantage of QPSO algorithm is that it
uses only one parameter control. The critical step or QPSO algorithm is the choice
of suitable attractive potential field that can guarantee bound states for the particles
moving in the quantum environment. In this article, one version of QPSO algorithm
was tested with two types of potential well: delta-potential well harmonic oscillator.
The main goal of this study is to show with of the potential field is the most suitable
for use in QPSO in a solution of the Nuclear Reactor Reload Optimization Problem,
especially in the cycle 7 of a Brazilian Nuclear Power Plant. All result were compared
with the performance of its classical counterpart of the literature and shows that
QPSO algorithm are well situated among the best alternatives for dealing with hard
optimization problems, such as NRROP. (author)$$$$

The ray-tracing code Zgoubi has been used in a number of projects, in the frame of
high energy and nuclear physics R and D, since it was last documented in review articles.
Its library of optical elements and its accelerator simulation tools have been further
developed in these contexts. Its use covers design studies regarding large colliders
such as LHC and RHIC, synchrotron radiation, short lived beams, acceleration of polarized
lepton and hadron beams. This report gives an overview of the present state of the
code and of its evolution, illustrated with examples aimed at highlighting its capabilities$$$$

http://dx.doi.org/10.1070/RM2013v068n04ABEH004850by Deza, M (Ecole Normale Superieure, Paris (France)); Dutour Sikirić, M (Rudjer Boškovic Institute, Zagreb (Croatia)); Shtogrin, M I (P.G.Demidov Yaroslavl State University (Russian Federation)) Read MoreCollapse

[en]

A geometric fullerene, or simply a fullerene, is the surface of a simple closed convex
3-dimensional polyhedron with only 5- and 6-gonal faces. Fullerenes are
geometric models for chemical fullerenes, which form an important class of organic
molecules. These molecules have been studied intensively in chemistry, physics, crystallography,
and so on, and their study has led to the appearance of a vast literature on fullerenes
in mathematical chemistry and combinatorial and applied geometry. In particular, several
generalizations of the notion of a fullerene have been given, aiming at various
applications. Here a new generalization of this notion is proposed: an n-disk-fullerene.
It is obtained from the surface of a closed convex 3-dimensional polyhedron which
has one n-gonal face and all other faces 5- and 6-gonal, by removing the n-gonal face.
Only 5- and 6-disk-fullerenes correspond to geometric fullerenes. The notion
of a geometric fullerene is therefore generalized from spheres to compact simply
connected two-dimensional manifolds with boundary. A two-dimensional surface is said
to be unshrinkable if it does not contain belts, that is, simple cycles consisting
of 6-gons each of which has two neighbours adjacent at a pair of opposite edges.
Shrinkability of fullerenes and n-disk-fullerenes is investigated. Bibliography: 87
titles$$$$

242 KB - http://www.iaea.org/inis/collection/NCLCollectionStore/_Public/45/091/45091439.pdf - Text Version by Piovezan, Pamela; Carluccio, Thiago (Centro Tecnologico da Marinha (CTMSP), Sao Paulo, SP (Brazil). Dept. de Neutronica
e Blindagem); Abe, Alfredo; Santos, Adimir dos (Instituto de Pesquisas Energeticas
e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)), E-mail: pamela.piovezan@ctmsp.mar.mil.br, E-mail: thiago.carluccio@ctmsp.mar.mil,
E-mail: alfredo@ctmsp.mar.mil.br, E-mail: asantos@ipen.br; Associacao Brasileira de Energia Nuclear (ABEN), Rio de Janeiro, RJ (Brazil) Read MoreCollapse

[en]

A new component named heavy reflector that did not exist in actual nuclear power plants
was introduced recently by the EPR reactor. The component was designed to partially
reflect neutrons inside the core to increase fuel efficiency and protect the vessel
during its 60-year operational life. Recently, an experiment was designed and performed
to address the real neutron reflector contribution due to the stainless steel in the
IPEN/MB-01 research reactor. The experiment consisted of several plates of stainless
steel which were conveniently positioned at water reflector region of the reactor
core. The main experimental results were the critical control bank positions and reactivity
as a function of the number of stainless steel plates. The main outcome of the experimental
results showed a quite clear effect on neutron absorption and neutron reflection due
to the stainless steel plates. The objective of this preliminary work is to address
theoretically this experiment using the diffusion theory code CITATION, besides existing
evaluation using Monte Carlo (MCNP and Tripoli) and transport (TORT) codes, in order
to verify the performance of diffusion theory for the reflector region. (author)$$$$