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Before genotyping microarrays can be used, calling algorithms must first be calibrated with a control set. Calling algorithms that evaluate hybridization intensity data on the basis of individual markers are better able to compensate for sequence specific variations. However, they require that the control set includes samples sufficient to exercise every marker in all of its allelic states. Minimizing...
In recent years, active prosthetic legs have been developed and deployed commercially that help amputees to initiate gait with less effort and more symmetry in the pattern. However, the process of initial set up and tuning is highly time and cost consuming. It requires prosthetic experts to observe the gait and the feedback from amputees to manually tune the parameters subjectively. In this study,...
In this paper, a system based on concepts of MultiAgent Cooperative Systems is designed. It allows synchronizing inverters from two consensus Algorithms. This approach is made to designing smart devices (Smart inverters) through communicating the state among all the inverters by the Multi-Agent network in order to maintain stable frequency, phase, and voltage. The inverter is controlled by a deadbeat...
We present a novel class of ultrathin metasurfaces operating in a nonlinear regime, simultaneously providing generation efficiencies that are many orders of magnitude larger than in other nonlinear setups, and, at the same time, capable of controlling the local phase of the nonlinear signal with high precision and subwavelength resolution. The key to achieving such outstanding performance is combining...
We explore the unusual electromagnetic response of magnetically-biased densely-packed graphene ribbons. Applying an effective medium approach, we show how the presence of a magnetostatic bias induces resonances on all components of the effective conductivity tensor, significantly enriching the features of the supported surface plasmons polaritons (SPPs). Specifically, we demonstrate magnetically-induced...
We explore the electromagnetic response of ultrathin metasurfaces realized by densely-packed arrays of graphene strips. We analyze various topologies of propagation bands supported by this structure, ranging from the canalization regime found at a few terahertz (THz), hyperbolic responses present at a few dozens of THz, and anisotropic elliptic TE and TM regimes that arise at mid-infrared frequencies...
We describe a novel class of ultrathin plasmonic metasurfaces able to provide nonlinear conversion efficiencies many orders of magnitude larger than any other nonlinear flat setup previously reported. This large efficiency is achieved over subwavelength thickness, avoiding the use of cumbersome phase matching techniques. In addition, we show how such metasurfaces can be designed to provide full control...
Nowadays, the solid-sate lighting technology evolution has changed traditional solutions in lighting. High-Brightness Light-Emitting Diodes (HB-LEDs) have become very attractive light sources due to their excellent characteristics: high efficiency, high life-time and low maintenance. It is evident that HB-LED drivers must be durable and efficient to achieve these advantages. Moreover, for replacing...
In this paper the implementation of a low cost Fiber Bragg Grating (FBG) sensor interrogation system is presented. It uses two FBGs for comparison and measures the power between the FBGs signals using an embedded system. The system has been implemented for the 1550 nm band. The performance of the system was tested with a broadband source and doing temperature variations in one of the two FBGs, obtaining...
Active equalizers, with a higher efficiency in comparison to passive ones, have the disadvantage of using a considerable number of components. The wave-trap concept allows the battery cell equalizer to use its switching frequency as the control variable that decides which cell is being charged. Hence, the number of controlled switches is strongly reduced without reducing the performance of the system...
The properties of surface plasmons supported by infinitesimally thin hyperbolic metasurfaces are investigated in detail. Hyperbolic metasurfaces are rigorously modelled using uniaxial conductivity tensors, thus taking into account their combined dielectric/metallic nature. The dispersion relation of the supported modes is analytically derived and asymptotically simplified to closely follow the branches...
The pioneering theoretical and experimental research in terahertz graphene plasmonics developed by Prof. Julien Perruisseau-Carrier and his group is reviewed. From the experimental point of view, Prof. Perruisseau-Carrier determined the reconfigurable EM properties of graphene in different frequency bands and introduced self-biased graphene-based structures with enhanced performance and unprecedented...
A cascode rectifier structure brings the advantage of very low conduction losses due to its low forward voltage drop and dynamic resistance. The main application of this structure is the front-end rectifiers for AC/DC power converters and OR power gates for power converters in parallel connection, where they can achieve an improvement of the overall efficiency thanks to the previous advantage. However,...
Currently acknowledged, as a rapidly emerging technology, High-Brightness Light-Emitting Diodes (HB-LEDs) are considered the true alternative to many mature technologies (i.e., incandescent bulbs, compact fluorescent lamps, etc.) due to their high efficiency, low maintenance and durability. It is evident that the HB-LED driver must be durable and efficient to achieve these advantages. Moreover, in...
Envelope Tracking (ET) and Envelope Elimination and Restoration (EER) are techniques which were designed to increase the efficiency of Radio Frequency Power Amplifiers (RF PA) while maintaining a strong linearity of the system. Both techniques employ a special type of DC/DC converter called Envelope Modulator or Envelope Amplifier which has attracted the interest of Spanish power electronics and communications...
The use of techniques such as envelope tracking (ET) and envelope elimination and restoration (EER) can improve the efficiency of radio frequency power amplifiers (RFPA). In both cases, high-bandwidth DC/DC converters called envelope amplifiers (EA) are used to modulate the supply voltage of the RFPA. This paper addresses the analysis and design of a modified two-phase Buck converter optimized to...
The development of Green's Functions (GF) for structures including graphene layers is a keypoint for the design and analysis of future graphene-based antenna components. Their properties and computational challenges are presented and discussed within this contribution. Additionally, a novel computational technique that offers high evaluation speed and good accuracy for calculating such GFs is proposed...
Achieving soft switching in primary switches and reducing switching losses in the secondary ones make of the Asymmetrical Half Bridge (AHB) a suitable topology for many high-performance applications. Besides, the lack of dead times, except those needed for achieving soft switching, is a very interesting feature for self-driven synchronous rectification. On the other hand, it also has some disadvantages...
The new wide band-gap semiconductor devices provide new properties to be explored. Normally-on Silicon Carbide (SiC) JFET power devices have several advantages, in particular low switching losses, high temperature operation and high reverse voltage capability. Looking for improve the overall efficiency in power converters, new structures based on these power devices might be studied. In this paper,...
We present parallelization of single and two phase flow CFD solvers on a graphics processing unit (GPU) platform. Numerical simulations are done for some standard benchmark test cases for both single and two phase flow solvers. The formulation is based on finite volume method with SMAC algorithm on regular cartesian and collocated grid. Volume of fluid method in used for tracking the interface in...
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