Geometry Of Numbers
Mostrando 1-12 de 27 artigos, teses e dissertações.
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1. A New Miniaturized Low-Profile and Stable Dual-Band FSS with 2.5D Structure for ISM Bands
Abstract Based on 2.5-Dimensional (2.5D) frequency selective surface (FSS) structures, a new miniaturized frequency selective surface structure is proposed in this work to operate as a bandreject filter in the 2.4 GHz (2400 to 2483.5 MHz) and 5 GHz (5150 to 5350 MHz and 5470 to 5725 MHz) ISM (Industrial, Scientific, and Medical) bands. The FSS has the metall
Journal of Microwaves, Optoelectronics and Electromagnetic Applications. Publicado em: 2022
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2. Investigation of a NACA0012 Finite Wing Aerodynamics at Low Reynold’s Numbers and 0º to 90º Angle of Attack
ABSTRACT: The aerodynamic characteristics of a NACA0012 wing geometry at low Reynold’s numbers and angle of attack ranging from 0º to 90º are investigated using numerical simulations and the results are validated by wind tunnel experiments. Further experiments are conducted at low Reynold’s numbers of 1 × 105, 2 × 105 and 3 × 105. Findings of the st
J. Aerosp. Technol. Manag.. Publicado em: 28/03/2019
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3. Investigation of the Energy Absorption Characteristics of Metallic Tubes with Curvy Stiffeners under Dynamic Axial Crushing
Abstract Thin walled multi-cell columns are highly efficient energy absorbers under axial compressions. Multi-cell features are usually obtained by placing stiffeners or ribs to get the required geometry features in the columns. In this study, the curved stiffeners with varying numbers in different configurations are used to support the circular single and b
Lat. Am. j. solids struct.. Publicado em: 2017-08
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4. Investigation of the Energy Absorption Characteristics of Metallic Tubes with Curvy Stiffeners under Dynamic Axial Crushing
Abstract Thin walled multi-cell columns are highly efficient energy absorbers under axial compressions. Multi-cell features are usually obtained by placing stiffeners or ribs to get the required geometry features in the columns. In this study, the curved stiffeners with varying numbers in different configurations are used to support the circular single and b
Lat. Am. j. solids struct.. Publicado em: 2017-08
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5. Finite volume simulation of 2-D steady square lid driven cavity flow at high reynolds numbers
In this work, computer simulation results of steady incompressible flow in a 2-D square lid-driven cavity up to Reynolds number (Re) 65000 are presented and compared with those of earlier studies. The governing flow equations are solved by using the finite volume approach. Quadratic upstream interpolation for convective kinematics (QUICK) is used for the app
Braz. J. Chem. Eng.. Publicado em: 2013-12
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6. Aplicabilidade e validação do Geant4 para fótons e elétrons em radioterapia / GEANT4 applicability and validation to Photons and Electrons in Radiotherapy
Due to the increasing use of ionizing radiation in medical applications, in recent decades, the simulation codes for radiation interacting with matter, based on Monte Carlo Method, have been constantly adapted to applications in medical physics. TheMonte Carlo method is a statisticalmethod of numerical simulation of problems using essentially a sequence of r
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 14/06/2011
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7. Síntese, Caracterização Estrutural e Propriedades Luminescentes de Complexos de Lantanídeos (III) com Hidrazonas e Semicarbazonas derivadas da 2,6-Diformilpiridina e com Triazenos 1-óxidos. / Synthesis, Structural Characterization and Luminescent Properties of Complexes of Lanthanides (III) with Hydrazones and Semicarbazones derived from 2,6-diformylpyridine and Triazenes 1-oxides.
Lanthanide complexes with ligands containing oxygen and nitrogen as donor atoms have been investigated in this study aiming to explore the coordinative behavior of metals with high coordination numbers, as well as a study of luminescence properties of new complexes. The chosen ligands were hydrazones and semicarbazones derived from 2,6-diformylpyridine and t
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 201103
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8. The density of lattice sphere packings / A densidade de empacotamentos esfericos em reticulados
This dissertation addresses the lattice theory with focus on packing density, which has many applications and allows to establish interesting connections between topics of linear algebra, calculus of several variables and discrete geometry. The first chapter is an introduction to the main concepts and properties of lattices. In the second chapter we discuss
Publicado em: 2009
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9. Otimização das formas de cascos de deslocamento em relação a sua resistência ao avanço. / Displacement hull optimization regarding to ship wave resistance.
Due to an increasing necessity of building new vessels, whether by new orders or fleet renewal, the development of computational programs that could allow optimization of hull shapes is always helpful, saving project time and ensuring better performance at sea. Thus, the development of a synthesis procedure that allows obtaining shapes with better performanc
Publicado em: 2008
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10. Comportamento do hidrociclone filtrante frente às modificações no diâmetro de underflow e no tubo de vortex finder
Filtering hydrocyclones are similar equipaments to the conventional hydrocyclone except by the fact they have filtering conical region. In this way, during the operation of this equipament, besides the feed streams, the underflow and the overflow, observed commonly, the porous conical region produces liquid by the filtration process. The filtration in the co
Publicado em: 2008
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11. Análise numérica do escoamento em uma sala retangular ventilada por um jato horizontal de parede
The present work investigates the three-dimensional turbulent airflow in a room ventilated by a horizontal wall jet. The geometry of Nielsen s experiment (Nielsen et al., 1978), for which experimental and numerical results for some turbulence models are available in the current literature, has been adopted in this work. This experiment consists of a rectangu
Publicado em: 2007
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12. Síntese e Análise Estrutural de Complexos de Urânio(VI) com Hidrazonas, Semicarbazonas e Ligantes Relacionados. / Synthesis and Structural Analysis of Uranium(VI) Complexes with Hydrazones, Semicabazones and Related Ligands.
Uranyl complexes with ligands with oxygen and nitrogen donors have been extensively reviewed and they have aroused interest on account of their high stability, usefulness in selective chemical separations and their formation in higher coordination numbers, but quite a few complexes of hydrazone and semicarbazone ligands have been reported. This fact was the
Publicado em: 2006