93,311 research outputs found
Benford's Law and articles of scientific journals: comparison of JCR(A (R)) and Scopus data
Benford's Law is a logarithmic probability distribution function used to predict the distribution of the first significant digits in numerical data. This paper presents the results of a study of the distribution of the first significant digits of the number of articles published of journals indexed in the JCR(A (R)) Sciences and Social Sciences Editions from 2007 to 2011. the data of these journals were also analyzed by the country of origin and the journal's category. Results considering the number of articles published informed by Scopus are also presented. Comparing the results we observe that there is a significant difference in the data informed in the two databases.Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)INPE, Natl Inst Space Res, BR-12227010 Sao Jose Dos Campos, SP, BrazilUniversidade Federal de São Paulo, UNIFESP, BR-12231280 Sao Jose Dos Campos, SP, BrazilITA, Aeronaut Inst Technol, BR-12228900 Sao Jose Dos Campos, SP, BrazilUniversidade Federal de São Paulo, UNIFESP, BR-12231280 Sao Jose Dos Campos, SP, BrazilWeb of Scienc
Deep Inelastic Scattering in Holographic AdS/QCD Models
We review the description of deep inelastic scattering using some AdS/QCD
phenomenological models.Comment: Talk presented by NRFB at Light Cone 2009: Relativistic Hadronic and
Particle Physics, 8-13 Jul 2009, Sao Jose dos Campos, Brazi
The ITASAT CubeSat Development and Design
Because they are inexpensive platforms for satellites, CubeSats have become a low-cost way for universities and even developing countries to have access to space technology. This paper presents the ITASAT design, particularly the Attitude Determination and Control Subsystem, the Onboard Software, and the Assembly, Integration and Testing program. The ITASAT is a 6U CubeSat nano-satellite in development at the Instituto Tecnologico de Aeronautica, in Sao Jose dos Campos, Brazil. The platform and its subsystems will be provided by industry while the payloads are being designed and developed by the principal investigators. The ITASAT Attitude Determination and Control Subsystem will rely on a 3-axis magnetometer, 6 analog cosine sun sensors, 3-axis MEMS gyroscopes, 3 magnetic torque coils, and 3 reaction wheels. The Attitude Determination and Control Subsystem operating modes, control laws, and embedded software are under the responsibility of the Instituto Tecnologico de Aeronautica. A Kalman filter shall be employed to estimate the quaternion attitude and gyroscope biases from sensor measurements. The Attitude Determination and Control Subsystem operating modes are the nominal mode, with geocentric pointing attitude control and the stabilization mode, in which only the satellite angular velocity is controlled. The nominal mode will be split into 2 sub-modes: reaction wheel control plus magnetic wheel desaturation and 3-axis magnetic attitude control. Simulation results have shown that the attitude can be controlled with 1-degree accuracy in nominal mode with the reaction wheels, but these errors grow as much as 20 degrees or higher with the 3-axis magnetic control.Inst Nacl Pesquisas Espaciais Engn, Sao Jose Dos Campos, SP, BrazilTecnol Espaciais Div Mecan Espacial Control, Sao Jose Dos Campos, SP, BrazilInst Tecnol Aeronaut, Dept Ciencia & Tecnol Aeroespacial, Div Engn Aeronaut, Praca Marechal Eduardo Gomes 50 Vila Acacias, BR-12230901 Sao Jose Dos Campos, SP, BrazilUniv Fed Sao Paulo, Inst Ciencia & Tecnol, Dept Ciencia Computacao, Sao Jose Dos Campos, SP, BrazilUniv Fed Sao Paulo, Inst Ciencia & Tecnol, Dept Engn Computacao, Sao Jose Dos Campos, SP, BrazilInst Tecnol Aeronaut, Dept Ciencia & Tecnol Aeroespacial, Div Engn Eletr & Computacao, Sao Jose Dos Campos, SP, BrazilUniv Fed Sao Paulo, Inst Ciencia & Tecnol, Dept Engn Computacao, Sao Jose Dos Campos, SP, BrazilWeb of Scienc
New Identities from a Combinatorial Approach to Generalized Fibonacci and Generalized Lucas Numbers
We present here some new identities for generalizations of Fibonacci and Lucas numbers by combinatorially interpreting these numbers in terms of numbers of certain tilings of a 1 x m board. As a consequence, some new interesting identities involving the ordinaries Fibonacci and Lucas numbers are derived.CNPqFed Univ Sao Paulo UNIFESP, Dept Sci & Technol, BR-12247014 Sao Jose Dos Campos, SP, BrazilFed Univ Sao Paulo UNIFESP, Dept Sci & Technol, BR-12247014 Sao Jose Dos Campos, SP, BrazilWeb of Scienc
Tests of Universality of Baryon Form Factors in Holographic QCD
We describe a new exact relation for large QCD for the long-distance
behavior of baryon form factors in the chiral limit, satisfied by all 4D
semi-classical chiral soliton models. We use this relation to test the
consistency of the structure of two different holographic models of baryons.Comment: 4 pages. Talk presented by MN at Light Cone 2009: Relativistic
Hadronic and Particle Physics, 8-13 Jul 2009, Sao Jose dos Campos, Brazi
Characterization of SiC Thin Films Deposited by HiPIMS
In this work thin films of silicon carbide (SiC) were deposited on silicon wafers by High Power Impulse Magnetron Sputtering (HiPIMS) technique varying the average power of the discharge on a stoichiometric SiC target. X-ray diffraction, Raman spectroscopy, scanning electron microscopy and profilometry were used to analyze the films. It was observed that high values of the average electric power favors the formation of C-C bonds, while low values of the power promote the formation of Si-C bonds. At high power, we have also observed higher deposition rates, but the samples present surface imperfections, causing increase in the roughness and decrease in the film uniformity.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Inst Tecnol Aeronaut ITA, Ctr Tecn Aeroespacial CTA, BR-12228900 Sao Jose Dos Campos, SP, BrazilUniv Vale Paraiba, UNIVAP, BR-12244390 Sao Jose Dos Campos, SP, BrazilUniversidade Federal de São Paulo, UNIFESP, BR-12231280 Sao Jose Dos Campos, SP, BrazilUniversidade Federal de São Paulo, UNIFESP, BR-12231280 Sao Jose Dos Campos, SP, BrazilWeb of Scienc
Electromagnetic fluxes, monopoles, and the order of the 4d compact U(1) phase transition
We consider the 4d compact U(1) gauge theory with extended action
S=-beta sum_P cos theta_P -gamma sum_P cos 2 theta_P
We give a full characterization of the phase diagram of this model using the
notion of flux. The relation with the usual monopole picture is discussed. In
analogy with the XY model we consider the helicity modulus \cite{Jose:1977gm}
for this theory, and show that it is an order parameter. Analyzing the
finite-size effects of the helicity modulus we conclude that the transition is
first-order. The value of this order parameter is related to the renormalized
coupling beta_R. We measure beta^c_R at the transition point and give a
counterexample to its conjectured universal value \cite{Cardy:jg}.Comment: 39 pages and 25 figures. The determination of the renormalized
coupling has been improved. To appear in Nuclear Physics
Mesonic Spectrum from a Dynamical Gravity/Gauge model
Within a formulation of a Dynamical AdS/QCD model we calculate the spectrum
of light flavored mesons. The background fields of the model correspond to an
IR deformed Anti de Sitter metric coupled to a dilaton field. Confinement comes
as a consequence of the dilaton dynamics coupled to gravity. Additionally to
the Regge-like spectrum of light- scalar, vector and higher spin mesons, we
obtain the decay width of scalar mesons into two pions.Comment: Talk given at Light Cone 2009: Relativistic Hadronic and Particle
Physics (LC 2009), Sao Jose dos Campos, Brazil, 8-13 Jul 2009
Searching Less Perturbed Circular Orbits for a Spacecraft Travelling around Europa
Space missions to visit the natural satellite of Jupiter, Europa, constitute an important topic in space activities today, because missions to this moon are under study now. Several considerations have to be made for these missions. the present paper searches for less perturbed circular orbits around Europa. This search is made based on the total effects of the perturbing forces over the time, evaluated by the integral of those forces over the time. This value depends on the dynamical model and on the orbit of the spacecraft. the perturbing forces considered are the third-body perturbation that comes from Jupiter and the J(2), J(3,) and C-22 terms of the gravitational potential of Europa. Several numerical studies are performed and the results show the locations of the less perturbed orbits. Using those results, it is possible to find near-circular frozen orbits with smaller amplitudes of variations of the orbital elements.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Universidade Federal de São Paulo UNIFESP, Inst Ciencia & Tecnol, BR-12231280 Sao Jose Dos Campos, SP, BrazilInst Nacl Pesquisas Espaciais, BR-12243750 Sao Jose Dos Campos, SP, BrazilUniversidade Federal de São Paulo UNIFESP, Inst Ciencia & Tecnol, BR-12231280 Sao Jose Dos Campos, SP, BrazilCNPq: 303070/2011-0CNPq: 473387/2012-3CNPq: 304700/2009-6FAPESP: 2011/05671-5FAPESP: 2011/09310-7FAPESP: 2011/08171-3FAPESP: 2012/21023-6Web of Scienc
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