Numerical Precision
Mostrando 1-12 de 62 artigos, teses e dissertações.
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1. Practical rules for summing the series of the Tweedie probability density function with high-precision arithmetic
Abstract: For some ranges of its parameters and arguments, the series for Tweedie probability density functions are sometimes exceedingly difficult to sum numerically. Existing numerical implementations utilizing inversion techniques and properties of stable distributions can cope with these problems, but no single one is successful in all cases. In this wor
An. Acad. Bras. Ciênc.. Publicado em: 02/12/2019
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2. Numerical study of upstream disturbances on the performance of electromagnetic and ultrasonic flowmeters
ABSTRACT Electromagnetic and ultrasonic flowmeters are high precision devices that can measure the water flow in pressurized irrigation networks. In these networks, the inadequate installation distance of flow control valves generates upstream disturbances which will increase measurement errors and reduce the accuracy of the equipment. Therefore, estimating
Sci. agric. (Piracicaba, Braz.). Publicado em: 04/11/2019
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3. Rediscutindo Soluções Numéricas de Equações de Onda
Resumo Nesta contribuição, é nosso principal objetivo apresentar um método numérico de solução da equação de onda, seja esta de origem mecânica ou eletromagnética. Baseando-nos nesta solução, podemos avaliar o comportamento destas ondas sob diferentes aspectos e condições, visto que, as ondas eletromagnéticas conseguem se propagar no vácuo,
Rev. Bras. Ensino Fís.. Publicado em: 27/06/2019
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4. GFEM STABILIZATION TECHNIQUES APPLIED TO DYNAMIC ANALYSIS OF NON-UNIFORM SECTION BARS
Abstract The Finite Element Method (FEM), although widely used as an approximate solution method, has some limitations when applied in dynamic analysis. As the loads excite the high frequency and modes, the method may lose precision and accuracy. To improve the representation of these high-frequency modes, we can use the Generalized Finite Element Method (GF
Lat. Am. j. solids struct.. Publicado em: 29/10/2018
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5. Numerical experiments with the Generalized Finite Element Method based on a flat-top Partition of Unity
Abstract The Stable Generalized Finite Element Method (SGFEM) is essentially an improved version of the Generalized Finite Element Method (GFEM). Besides of retaining the good flexibility for constructing local enriched approximations, the SGFEM has the advantage of presenting much better conditioning than that of the conventional GFEM. Actually, bad conditi
Lat. Am. j. solids struct.. Publicado em: 29/10/2018
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6. A computational framework for predicting onset and crack propagation in composite structures via eXtended Finite Element Method (XFEM)
Abstract The eXtended Finite Element Method (XFEM) has been reliably used for analyzing crack growth in 3D structural elements over last years. In fact, many researchers have worked in this field, but it is scarce to find scientific contributions about 3D XFEM models applied to the failure of non-standard composite parts, such as tapered structures and thick
Lat. Am. j. solids struct.. Publicado em: 29/10/2018
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7. A New Approach for Investigation of Mode II Fracture Toughness in Orthotropic Materials
Abstract Estimation of mode II fracture toughness (KIIC) in composite materials is known as a troublous and crucial problem. Dissipated values of KIIC that are reported in different fracture mechanics references is the evidence of the mentioned claim. This problem can signify the necessity of modification on common test methods and fixtures. The present stu
Lat. Am. j. solids struct.. Publicado em: 14/05/2018
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8. Rollover Index for the Diagnosis of Tripped and Untripped Rollovers
Abstract It is necessary to detect danger as soon as possible to avoid rollover of a vehicle in sudden events. Using rollover index in real time can be used for this purpose. The traditional rollover indices currently applying in the vehicles can only detect the untripped rollover due to severe lateral acceleration in vehicles. These indices cannot detect th
Lat. Am. j. solids struct.. Publicado em: 2017
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9. Comparison of Developed Numerical Macro and Micro Masonry Models for Static and Dynamic Analysis of Masonry-infilled Steel Frames
Abstract First, the basic characteristics of macro and micro masonry models in numerical analyses of masonry structures are discussed. Afterwards, developed numerical macro and micro masonry models, intended for the nonlinear static and dynamic analysis of unreinforced and confined masonry walls, as well as of masonry-infilled frames, are briefly presented.
Lat. Am. j. solids struct.. Publicado em: 2016-12
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10. Experimental Magnetometer Calibration for Nanosatellites’ Navigation System
ABSTRACT This article deals with the problem of Earth’s magnetic field sensors calibration in the context of low-cost nanosatellites’ navigation systems. The attitude of space vehicles can be determined from the state estimation using information from three-axis inertial and non-inertial sensors. This study considers a three-axis solid-state magnetometer
J. Aerosp. Technol. Manag.. Publicado em: 2016-03
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11. Relative Motion Guidance, Navigation and Control for Autonomous Orbital Rendezvous
ABSTRACT: In this paper, the dynamics of the relative motion problem in a perturbed orbital environment are exploited based on Gauss' variational equations. The relative coordinate frame (Hill frame) is studied to describe the relative motion. A linear high fidelity model is developed to describe the relative motion. This model takes into account primary gra
J. Aerosp. Technol. Manag.. Publicado em: 2014-09
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12. Implementação de um algoritmo numérico para solução da equação de Christoffel generalizada em acustoelasticidade. / Implementation of a numerical algorithm for solution of the generalized Chistoffel equation in acoustoelasticity.
Extensive studies carried out in the last decades on the propagation of ultrasonic waves in solids led to the development of nondestructive techniques for the assessment of the safety and integrity of industrial structures and components. The interest in the application of ultrasound techniques for stress measurement for example comes from the measurable cha
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 31/08/2012