Search results for "S transform"
showing 10 items of 43 documents
Fractional wavelet transform
1997
The wavelet transform, which has had a growing importance in signal and image processing, has been generalized by association with both the wavelet transform and the fractional Fourier transform. Possible implementations of the new transformation are in image compression, image transmission, transient signal processing, etc. Computer simulations demonstrate the abilities of the novel transform. Optical implementation of this transform is briefly discussed.
Improved fast Gauss transform for meshfree electromagnetic transients simulations
2019
Abstract In this paper improved fast summations are introduced to enhance a meshfree solver for the evolution of the electromagnetic fields over time. The original method discretizes the time-domain Maxwell’s curl equations via Smoothed Particle Hydrodynamics requiring many summations on the first derivatives of the kernel function and field vectors at each time step. The improved fast Gauss transform is properly adopted picking up the computational cost and the memory requirement at an acceptable level preserving the accuracy of the computation. Numerical simulations in two-dimensional domains are discussed giving evidence of improvements in the computation compared to the standard formula…
ACCOUNTING AS A 21ST CENTURY BUSINESS VALUE DRIVER
2017
Companies have focused for decades on maximizing the value creation process of direct productive business activities. The information revolution has left its mark and has started an irreversible transformation of classical business processes and activities. In the new 21st century information and data driven society, commodity is value and knowledge, making Porters value chain concept an important key factor for successful and innovative businesses. Business value creation was during the industrial revolution a topic strictly liked to direct productive activities. The increased and transformed business environment required innovative and sustainable competitive advantages for business organ…
Broken rotor bars detection via Park's vector approach based on ANFIS
2014
Many attempts have been made on fault diagnosis of induction motors based on frequency and time domain analysis of stator current. In this paper, first the Park's vector transformation and frequency analysis for fault detection of induction motors are introduced. Then a smart approach using Adaptive Neuro Fuzzy Inference System (ANFIS) is proposed. This approach uses the time domain features derived from the Park's vector transformation of stator current. By the proposed method, a partial break including 5 mm crack on a bar, one broken bar and two broken bars using experimental data are investigated. It will be shown that features derived from Park's vector compared to features obtained fro…
Exact simulation of first exit times for one-dimensional diffusion processes
2019
International audience; The simulation of exit times for diffusion processes is a challenging task since it concerns many applications in different fields like mathematical finance, neuroscience, reliability horizontal ellipsis The usual procedure is to use discretization schemes which unfortunately introduce some error in the target distribution. Our aim is to present a new algorithm which simulates exactly the exit time for one-dimensional diffusions. This acceptance-rejection algorithm requires to simulate exactly the exit time of the Brownian motion on one side and the Brownian position at a given time, constrained not to have exit before, on the other side. Crucial tools in this study …
La semilla sembrada: el potencial transformador de la justicia transicional y la restitución de tierras a mujeres en Colombia
2015
Esta tesis pone de relevancia la oportunidad que presentan las políticas de justicia transicional, en países que sufren o han sufrido violaciones sistemáticas de derechos humanos, para mostrar mediante sus mecanismos de Verdad, Justicia y Reparación, las causas estructurales de la violencia y sentar las bases para transformarlas. Así, el fin de esta investigación es clarificar si la justicia transicional debe y puede contribuir a generar condiciones de justicia social para los grupos sociales históricamente discriminados que han sido, por ello, víctimas de un conflicto armado generando así Garantías de No Repetición de la violencia. El estudio se contextualiza en el proceso de construcción …
Business models and opportunity creation: How IT entrepreneurs create and develop business models under uncertainty
2015
How can entrepreneurs develop business models for markets in which the technology is constantly changing-or create business models for markets that do not exist? These are fundamental questions for information technology IT entrepreneurs, and for information systems IS scholars who seek to develop a theoretical understanding of business models. The case study presented in this paper addressed these questions, demonstrating how a small software firm developed its business model over a 15-year period in cloud gaming markets. Based on the empirical findings, a preliminary theoretical model is presented. The aim of the model is to increase scholarly understanding of how business models are crea…
Shape memory NiTi thin films deposited at low temperature
1999
Abstract NiTi shape memory alloy (SMA) thin films have the potential to become high performance actuators for micro-electromechanical systems. Low temperature crystallized NiTi films would ensure a good compatibility with microelectronic processes and polymers. To avoid the drawbacks induced by annealing, we have tried to obtain low temperature crystallized RF sputtered NiTi films by optimising deposition parameters. We have found that NiTi films containing an excess of Ti (∼52%) were crystallized when deposited on Si(100) substrates heated up to only 473 K. NiTi/Si(n) Schottky diodes I–V characteristics showed a temperature dependence indicating structural transition in the NiTi electrode.…
Friction Stir Processing of NiTi Shape Memory Alloy: Microstructural Characterization
2010
Shape Memory Alloys (SMA) are metal materials that, after being strained, come back to their original shape at a designated temperature. Welding NiTi alloys is not simple because when the material is melted, due to the high reactivity of the alloy elements, the typical shape memory properties may disappear. The solid state welding process, such as friction stir welding, is thus attractive for SMA joining and it exhibits potentials for achieving welded joints affected by microstructural changes that preserve the shape memory properties. The present study investigates the feasibility of friction stir welding process to join NiTi shape memory alloys; in order to analyse the welding process, it…
Structural and Magnetic Properties of Epitaxial Ni<sub>2</sub>MnGa Thin Films
2009
We report on the preparation and investigation of epitaxial thin films of the magnetic shape memory alloy Ni2MnGa. For samples close to the stoichiometric composition we find that the phase transformation temperature is affected by the crystallographic orientation. Changes in the crystal structure due to the transformation are observed using temperature-dependent X-ray diffraction. Films with higher manganese content are in the martensitic state at room temperature. Those samples on Al2O3(11-20) reveal the 7-layered orthorhombic structure that allows strains up to 10 %. To avoid blocking of magnetostrictive effects by the substrate, free-standing films are prepared using water-soluble NaCl(…