2019 International Conference on Electromagnetics in Advanced Applications (ICEAA), 2019
Despite its several qualities, the Poggio-Miller-Chang-Harrington-Wu-Tsai (PMCHWT) formulation fo... more Despite its several qualities, the Poggio-Miller-Chang-Harrington-Wu-Tsai (PMCHWT) formulation for simulating scattering by dielectric media suffers from numerical instabilities and severe ill-conditioning at low frequencies. While this drawback has been the object of numerous solution attempts in the standard low-frequency breakdown regime for scattering problems, the eddy-current regime requires a specific treatment. In this contribution, we present an extension of the recently introduced quasi-Helmholtz projectors based preconditioning of the PMCHWT to obtain an equation stable at low frequencies and specifically in three regimes relevant for eddy currents analyses: (i) when the frequency decreases with a constant conductivity, (ii) when the conductivity increases at fixed frequency and (iii) when the frequency decreases while keeping the product of the frequency and the conductivity constant. Being based on quasi-Helmholtz projectors our new strategy does not further degrade the conditioning of the original equation and is compatible with existing fast solvers. The resulting full-wave formulation is capable of smoothly transitioning from simulations at high frequencies to the different low-frequency regimes which encompass, in particular, eddy currents applications. Numerical results demonstrate the validity of our approach in all the regimes with a special emphasis given to eddy currents.
Two templates files in Excel and two examples in .html files. You need to DOWNLOAD the html files... more Two templates files in Excel and two examples in .html files. You need to DOWNLOAD the html files and use a browser to see them<br>
Ever been attacked by malicious code leaving unknown files all over your computer? Trying to figu... more Ever been attacked by malicious code leaving unknown files all over your computer? Trying to figure out if a file is encrypted or just compressed? Is the file really something else? Is there hidden data? Are you short on time! This talk leads you through file identification and analysis using some custom FREE tools that apply statistics and visualization to answer these questions and more. You can often identify files by their statistical picture and I am going to show you how. We can find some hidden data (steganalysis), easily determine if an executable file is packed or obfuscated, find appended data, figure out if the file is really what it purports to be and even aid in reversing XOR encryption. The final proof of concept program allows you to statistically identify (i.e. no magic numbers or header information used) some file types autonomously for an entire hard drive. The Windows-based tools (mostly math so adaptable to Linux) and source code are free! John Ortiz is currently...
INCLUDES AN IMPLANT occlusive an elongate member having an end, a proximal portion to that end an... more INCLUDES AN IMPLANT occlusive an elongate member having an end, a proximal portion to that end and a distal portion to that. NEXT PART IS ENOUGH THAT MAY flexible to fold in on itself and maintain that configuration without additional support. At least a portion of the distal part is preformed to have a first configuration When in a first state and a second configuration when in a second state. The second configuration of the distal portion has a flow resistance substantially greater than the proximal portion. WHEN IN THE REGION TO DOWNLOAD BE OCCLUDED, THE NEXT PART IS REQUIRED TO BE INTRODUCED IN A MASS around at least part of the secondary structure of the distal portion. CONFORMS AS MASS, FITS IN WALL frictionally vascularization SURROUNDING AND ANCHOR IMPLANT TO THE SAME.
SDAR is an analytical package designed for both plotting and facilitate the analysis of Stratigra... more SDAR is an analytical package designed for both plotting and facilitate the analysis of Stratigraphic Data. SDAR uses simple stratigraphic data and takes advantage of the flexible plotting tools available in R to produce detailed stratigraphic columns (SCs). SDAR is used to generate accurate and complete SC plot including multiple features (e.g., lithology, grain size, sedimentary structures, bioturbation, fossil content, color). The development of this package was supported by Carlos Jaramillo, Center for Tropical Paleoecology and Archaeology at Smithsonian Tropical Research Institute.
2019 International Conference on Electromagnetics in Advanced Applications (ICEAA), 2019
Despite its several qualities, the Poggio-Miller-Chang-Harrington-Wu-Tsai (PMCHWT) formulation fo... more Despite its several qualities, the Poggio-Miller-Chang-Harrington-Wu-Tsai (PMCHWT) formulation for simulating scattering by dielectric media suffers from numerical instabilities and severe ill-conditioning at low frequencies. While this drawback has been the object of numerous solution attempts in the standard low-frequency breakdown regime for scattering problems, the eddy-current regime requires a specific treatment. In this contribution, we present an extension of the recently introduced quasi-Helmholtz projectors based preconditioning of the PMCHWT to obtain an equation stable at low frequencies and specifically in three regimes relevant for eddy currents analyses: (i) when the frequency decreases with a constant conductivity, (ii) when the conductivity increases at fixed frequency and (iii) when the frequency decreases while keeping the product of the frequency and the conductivity constant. Being based on quasi-Helmholtz projectors our new strategy does not further degrade the conditioning of the original equation and is compatible with existing fast solvers. The resulting full-wave formulation is capable of smoothly transitioning from simulations at high frequencies to the different low-frequency regimes which encompass, in particular, eddy currents applications. Numerical results demonstrate the validity of our approach in all the regimes with a special emphasis given to eddy currents.
Two templates files in Excel and two examples in .html files. You need to DOWNLOAD the html files... more Two templates files in Excel and two examples in .html files. You need to DOWNLOAD the html files and use a browser to see them<br>
Ever been attacked by malicious code leaving unknown files all over your computer? Trying to figu... more Ever been attacked by malicious code leaving unknown files all over your computer? Trying to figure out if a file is encrypted or just compressed? Is the file really something else? Is there hidden data? Are you short on time! This talk leads you through file identification and analysis using some custom FREE tools that apply statistics and visualization to answer these questions and more. You can often identify files by their statistical picture and I am going to show you how. We can find some hidden data (steganalysis), easily determine if an executable file is packed or obfuscated, find appended data, figure out if the file is really what it purports to be and even aid in reversing XOR encryption. The final proof of concept program allows you to statistically identify (i.e. no magic numbers or header information used) some file types autonomously for an entire hard drive. The Windows-based tools (mostly math so adaptable to Linux) and source code are free! John Ortiz is currently...
INCLUDES AN IMPLANT occlusive an elongate member having an end, a proximal portion to that end an... more INCLUDES AN IMPLANT occlusive an elongate member having an end, a proximal portion to that end and a distal portion to that. NEXT PART IS ENOUGH THAT MAY flexible to fold in on itself and maintain that configuration without additional support. At least a portion of the distal part is preformed to have a first configuration When in a first state and a second configuration when in a second state. The second configuration of the distal portion has a flow resistance substantially greater than the proximal portion. WHEN IN THE REGION TO DOWNLOAD BE OCCLUDED, THE NEXT PART IS REQUIRED TO BE INTRODUCED IN A MASS around at least part of the secondary structure of the distal portion. CONFORMS AS MASS, FITS IN WALL frictionally vascularization SURROUNDING AND ANCHOR IMPLANT TO THE SAME.
SDAR is an analytical package designed for both plotting and facilitate the analysis of Stratigra... more SDAR is an analytical package designed for both plotting and facilitate the analysis of Stratigraphic Data. SDAR uses simple stratigraphic data and takes advantage of the flexible plotting tools available in R to produce detailed stratigraphic columns (SCs). SDAR is used to generate accurate and complete SC plot including multiple features (e.g., lithology, grain size, sedimentary structures, bioturbation, fossil content, color). The development of this package was supported by Carlos Jaramillo, Center for Tropical Paleoecology and Archaeology at Smithsonian Tropical Research Institute.
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