Browsing Simulation of Wave Propagation by Title
Now showing items 120 of 205

1.5D BASED INVERSION OF LOGGINGWHILEDRILLING RESISTIVITY MEASUREMENTS IN 3D FORMATIONS
(201706)This manuscript describes an extension of a computer method developed for the fast inversion of loggingwhiledrilling (LWD) resistivity measurements Pardo and TorresVerdín (2015); Bakr et al. (2016). The method enables ... 
1D Painless Multilevel Automatic GoalOriented h and p Adaptive Strategies Using a PseudoDual Operator
(20220101)The main idea of our GoalOriented Adaptive (GOA) strategy is based on performing global and uniform h or prefinements (for h and padaptivity, respectively) followed by a coarsening step, where some basis functions are ... 
2.5D Deep Learning Inversion of LWD and DeepSensing em Measurements Across Formations with Dipping Faults
(20220101)Deep learning (DL) inversion of induction logging measurements is used in well geosteering for realtime imaging of the distribution of subsurface electrical conductivity. We develop a DL inversion workflow to solve 2.5D ... 
3D hpAdaptive Finite Element Simulations of Bend, Step, and MagicT Electromagnetic Waveguide Structures
(201403)Metallic rectangular waveguides are often the preferred choice on telecommunication systems and medical equipment working on the upper microwave and millimeter wave frequency bands due to the simplicity of its geometry, ... 
5axis doubleflank CNC machining of spiral bevel gears via customshaped milling tools  Part I: modeling and simulation
(20191120)A new category of 5axis flank computer numerically controlled (CNC) machining, called \emph{doubleflank}, is presented. Instead of using a predefined set of milling tools, we use the shape of the milling tool as a free ... 
5axis doubleflank CNC machining of spiral bevel gears via customshaped tools – Part II: physical validations and experiments
(202110)Recently, a new methodology for 5axis flank computer numerically controlled (CNC) machining, called doubleflank machining, has been introduced (see “5axis doubleflank CNC machining of spiral bevel gears via customshaped ... 
Accessibility for LineCutting in Freeform Surfaces
(20190426)Manufacturing techniques such as hotwire cutting, wireEDM, wiresaw cutting, and flank CNC machining all belong to a class of processes called linecutting where the cutting tool moves tangentially along the reference ... 
Adaptive Solution of a SingularlyPerturbed ConvectionDiffusion Problem Using a Stabilized Mixed Finite Element Method
(20190105)We explore the applicability of a new adaptive stabilized dualmixedfinite element method to a singularlyperturbed convectiondiffusion equation withmixed boundary conditions. We establish the rate of convergence when the ... 
Adjointbased formulation for computing derivatives with respect to bed boundary positions in resistivity geophysics
(201902)In inverse geophysical resistivity problems, it is common to optimize for specific resistivity values and bed boundary positions, as needed, for example, in geosteering applications. When using gradientbased inversion ... 
An AgentOriented Hierarchic Strategy for Solving Inverse Problems
(20151231)The paper discusses the complex, agentoriented hierarchic memetic strategy (HMS) dedicated to solving inverse parametric problems. The strategy goes beyond the idea of twophase global optimization algorithms. The global ... 
Algebraic equations for constant width curves and Zindler curves
(202203)An explicit method to compute algebraic equations of curves of constant width and Zindler curves generated by a family of middle hedgehogs is given thanks to a property of Chebyshev polynomials. This extends the methodology ... 
An Algorithm based on continuation techniques for minimization problems with highly non linear equality constraints
(2021)We present an algorithm based on continuation techniques that can be applied to solve numerically minimization problems with equality constraints. We focus on problems with a great number of local minima which are hard to ... 
Analysis of extreme wave events on the southern coast of Brazil
(20141231)Using the wave model SWAN (simulating waves nearshore), high waves on the southwestern Atlantic generated by extratropical cyclones are simulated from 2000 to 2010, and their impact on the Rio Grande do Sul (RS) coast is ... 
Approximations for traveltime, slope, curvature, and geometrical spreading of elastic waves in layered transversely isotropic media
(202110)Each seismic body wave, including quasi compressional, shear, and converted wave modes, carries useful subsurface information. For processing, imaging, amplitude analysis, and forward modeling of each wave mode, we need ... 
Arithmetic method of doubleinjectionelectrode model for resistivity measurement through metal casing
(20101231)Throughcasing resistivity (TCR) measurement instruments such as Cased Hole Formation Resistivity are extensively used for the dynamic monitoring of oil reservoirs during the production phase in oil wells to evaluate the ... 
Asymptotic Models for the Electric Potential across a Highly Conductive Casing
(201807)We analyze a configuration that involves a steelcased borehole, where the casing that covers the borehole is considered as a highly conductive thin layer. We develop an asymptotic method for deriving reduced problems ... 
Automatic fitting of conical envelopes to freeform surfaces for flank CNC machining
(201710)We propose a new algorithm to detect patches of freeform surfaces that can be well approximated by envelopes of a rotational cone under a rigid body motion. These conical envelopes are a preferable choice from the ... 
Automatic RedChannel underwater image restoration
(20151231)Underwater images typically exhibit color distortion and low contrast as a result of the exponential decay that light suffers as it travels. Moreover, colors associated to different wavelengths have different attenuation ... 
Bearing assessment tool for longitudinal bridge performance
(202009)This work provides an unsupervised learning approach based on a singlevalued performance indicator to monitor the global behavior of critical components in a viaduct, such as bearings. We propose an outlier detection ... 
A blackbox optimization of volumetric heating rate for reducing the wetness of the steam flow through turbine blades
(202101)This paper proposes to use a blackbox optimization to obtain the optimal volumetric heating required to reduce the wetness at the last stages of steam turbines. For this purpose, a global multiobjective optimization is ...