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Nomenclatura Unesco > (22) Física > (2203) Electrónica > (2203.02) Elementos de circuitos

Categorías relacionadas:
(3307.03) Diseño de circuitos

Mostrando recursos 1 - 20 de 467

1. Protección de circuitos para aplicaciones espaciales contra los efectos de rayos cósmicos - Cabañas García, Carlos; Rodríguez Carmona, Jaime
Los dispositivos implementados con tecnologías de última generación son cada vez más vulnerables a alteraciones en su comportamiento debido a la radiación cósmica. El objetivo de este trabajo es controlar esa posible vulnerabilidad. Esto sucede fundamentalmente en circuitos embarcados en aviones, satélites o cohetes. Nuestro trabajo consiste en adaptar una herramienta de inyección de errores que sólo funcionaba para tecnologías basadas en FPGA para que pueda ser usada sobre ASIC (Application-Specific Integrated Circuit). Esta herramienta llamada Nessy fue desarrollada por otros compañeros en esta facultad en proyectos de SSII durante los cursos académicos 2009/2010 y 2010/2011. Para ello se ha...

2. Evaluación de la resistencia a la corrosión de recubrimientos obtenidos por pulverización de un blanco de cromo mediante técnicas electroquímicas - Sandoval-Amador, Anderson Andrés; Peña Ballesteros, Dario Yesid; Piratoba Morales, Ulises
Se evaluó la resistencia a la corrosión de recubrimientos obtenidos por pulverización de un blanco de cromo sobre sustratos de acero AISI H13, mediante el análisis de espectroscopia de impedancia electroquímica (EIS) y curvas de polarización Tafel en una solución de NaCl al 3% en peso. Se encontró que estos recubrimientos presentan una velocidad de corrosión menor a la del sustrato, y que los datos de EIS se ajustan a un circuito eléctrico equivalente que contiene dos elementos de fase constante circuito típico para la interpretación del comportamiento de un electrodo metálico sobre el que ha sido depositado un recubrimiento...

3. METHODOLOGICAL CONSIDERATIONS OF DRIVE SYSTEM SIMULATION, WHEN COUPLING FINITE ELEMENT MACHINE MODELS WITH THE CIRCUIT SIMULATOR MODELS OF CONVERTERS. - Áron Szûcs
The paper discusses the issues with- and provides an overview of- the available methods for drive system simulation when the electrical machine is modeled by the finite element method (FEM) and the converter with the control is modeled by a circuit simulator. The main emphasis is placed on the necessity and accuracy of the simulation of the interaction between the subsystems: the electrical machine, the power electronics and the control logic.

4. Switch Using Radio Frequency Identification - Fink, Patrick W.; Lin, Gregory Y.; Kennedy, Timothy F.; Ngo, Phong H.
Disclosed is an apparatus for use as a switch. In one embodiment, the switch comprises at least one RFID tag, each RFID tag comprising an antenna element and an RFID integrated circuit, at least one source element, and at least one lever arm. Each lever arm is connected to one of the RFID tags, and each lever arm is capable of two positions. One of the positions places the lever arm and the RFID tag connected thereto into alignment with the source element. Other embodiments are also described.

5. DESIGN OF 11.8 MHZ BUNCHER FOR ISAC AT TRIUMF - A. K. Mitra; R. L. Poirier; R. E. Laxdal
The high energy beam transport (HEBT) line for the ISAC radioactive beam facility at TRIUMF requires an 11.8 MHz buncher. The main requirements of the buncher are to operate in cw mode with a velocity acceptance of 2.2 % and an effective voltage of 100 kV, which for a three gap buncher gives a drift tube voltage of 30 kV. A lumped element circuit is more suitable than a distributed rf structure for this low frequency of operation. The resonant frequency of 11.8 MHz is obtained by an inductive coil in parallel with the capacitance of the drift tube. The...

6. MODELING OF AN INDUCTIVE ADDER KICKER PULSER FOR DARHT-II * - L. Wang; G. J. Caporaso; E. G. Cook
An all solid-state kicker pulser for a high current induction accelerator (the Dual-Axis Radiographic Hydrodynamic Test facility DARHT-2) has been designed and fabricated. This kicker pulser uses multiple solid state modulators stacked in an inductive-adder configuration. Each modulator is comprised of multiple metal-oxidesemiconductor field-effect transistors (MOSFETs) which quickly switch the energy storage capacitors across a magnetic induction core. Metglas is used as the core material to minimize loss. Voltage from each modulator is inductively added by a voltage summing stalk and delivered to a 50 ohm output cable. A lumped element circuit model of the inductive adder has been developed...

7. A Tutorial on Transmission Line Transformers by - Chris Trask Nzwy
The concept of transmission line transformers (TLTs) has been a distinct element of RF circuit design at least since 1944 when Guanella disclosed an impedance transformer

8. Superconducting Qubits: A Short Review - M. H. Devoret; A. Wallraff; J. M. Martinis
Superconducting qubits are solid state electrical circuits fabricated using techniques borrowed from conventional integrated circuits. They are based on the Josephson tunnel junction, the only non-dissipative, strongly non-linear circuit element available at low temperature. In contrast to microscopic entities such as spins or atoms, they tend to be well coupled to other circuits, which make them appealling from the point of view of readout and gate implementation. Very recently, new designs of superconducting qubits based on multi-junction circuits have solved the problem of isolation from unwanted extrinsic electromagnetic perturbations. We discuss in this review how qubit decoherence is affected by...

9. Broadband, Efficient, Electrically Small Metamaterial-Inspired Antennas Facilitated by Active Near-Field Resonant Parasitic Elements - Peng Jin; Student Member; Richard W. Ziolkowski
Abstract—The possibility of using an active internal matching element in several types of metamaterial-inspired, electrically small antennas (ESAs) to overcome their inherent narrow bandwidths is demonstrated. Beginning with the Z antenna, which is frequency tunable through its internal lumped element inductor, a circuit model is developed to determine an internal matching network, i.e., a frequency dependent inductor, which leads to the desired enhanced bandwidth performance. An analytical relation between the resonant frequency and the inductor value is determined via curve fitting of the associated HFSS simulation results. With this inductance-frequency relation defining the inductor values, a broad bandwidth, electrically small...

10. $rec.titulo - R Esearch A Rticles
of postsynaptic receptors, as a form of synaptic plasticity, to be a key element in associative memory formation. Circuit mechanisms of memory. By using molecular tagging techniques, we estimate that about a third of lateral amygdala neurons undergo plasticity during the formation of a memory driven by a single conditioning block. Because not all synapses on a plastic neuron undergo modification, one neuron may potentially participate in many memories, which allows combinatorial storage of a large number of memories (48–50). Perturbing plasticity in a small fraction of lateral amygdala neurons appears to be sufficient to reduce

11. Deslocalización electrónica en cadenas metálicas lineales unidas por sistemas π-conjugados - Río, M. Pilar del; Revuelta, M. A.; López, Ana M.; Ciriano, Miguel A.; Tejel, Cristina
La posibilidad de utilizar moléculas individuales como dispositivos electrónicos autónomos ha supuesto, en los últimos años, un amplio desarrollo de nuevas líneas de investigación. La electrónica molecular plantea el diseño de circuitos en los que algunos de sus elementos constituyentes serían los denominados “cables moleculares”. Dicho término se utiliza para describir moléculas discretas capaces de conectar dos especies de manera que pueda producirse un transporte de carga a través de la molécula.Cadenas metálicas lineales de iridio, comúnmente conocidas como azules de iridio, son candidatas perfectas para dicho fin, ya que permiten la deslocalización electrónica a través de los átomos metálicosque...

12. Structure Optimization of a Grain Impact Piezoelectric Sensor and Its Application for Monitoring Separation Losses on Tangential-Axial Combine Harvesters - Liang, Zhenwei; Li, Yaoming; Zhao, Zhan; Xu, Lizhang
Grain separation losses is a key parameter to weigh the performance of combine harvesters, and also a dominant factor for automatically adjusting their major working parameters. The traditional separation losses monitoring method mainly rely on manual efforts, which require a high labor intensity. With recent advancements in sensor technology, electronics and computational processing power, this paper presents an indirect method for monitoring grain separation losses in tangential-axial combine harvesters in real-time. Firstly, we developed a mathematical monitoring model based on detailed comparative data analysis of different feeding quantities. Then, we developed a grain impact piezoelectric sensor utilizing a YT-5 piezoelectric...

13. Análisis de los Circuitos Biosaludables para la Tercera Edad en la provincia de Málaga (España) (Analysis of the Public Geriatric Parks for Elderly People in Málaga (Spain)) - Hernández Aparicio, Elías; Fernández Rodríguez, Emilio; Merino Marbán, Rafael; Chinchilla Minguet, José Luis
El número de parques geriátricos o Circuitos Biosaludables que podemos encontrar en nuestras ciudades o municipios se ha incrementado desde la instalación del primero en 2005. Éstos han sido diseñados para cubrir unas determinadas necesidades y poder retrasar la aparición de los efectos del envejecimiento. El presente trabajo estudia las características y elementos de los Circuitos Biosaludables encontrados en los municipios de la provincia de Málaga. Para ello se ha pasado un cuestionario a los distintos ayuntamientos de las localidades que recogen aspectos sobre su uso, mantenimiento, elección y usuarios a los que está destinado. Además, para analizar su seguridad...

14. 3-Dimensional Finite Element Modeling of Integrated Circuit Capacitances - N. P. Van Der Meijs; A.J. van Genderen
INTRODUCTION With the decrease of feature sizes and the increase of chip dimensions in integrated circuit (IC) technology, the influence of interconnect capacitances on circuit performance is becoming more prominent. Therefore, the need for accurate prediction of interconnect capacitances --- to verify correct functionality of the chip before circuit fabrication, --- increases. At the same time, however, this problem becomes more difficult because lateral dimensions decrease more rapidly than vertical dimensions. As a result, traditional heuristic approaches to estimate the capacitances become inaccurate. Instead, rigorous mathematical techniques are required to model and determine interconnection capacitances. Possible techniques for this include...

15. Two-Frequency C–V Correction Using Five-Element Circuit Model for High-k Gate Dielectric and Ultrathin Oxide - Y. T. Hou; Y. Jin; H. J. Tao; S. C. Chen; M. S. Liang
Abstract—A new circuit model of five elements has been pro-posed for the two-frequency capacitance–voltage (C–V) correc-tion of high-k gate dielectric and ultrathin oxide. This five-element circuit model considered the static and dynamic dielectric losses in a lossy MOS capacitor, the parasitic well/substrate resistance, and the series inductance in the cables and probing system. Each of the circuit elements could be easily extracted from the two-frequency C–V and static current–voltage (I–V) measurements if some criteria are well satisfied. In addition, this model can also be transformed into another two four-element circuit models to sim-plify the analysis and calculations, depending on the...

16. Coupled Electromagnetic-Circuit Simulation of Arbitrarily-Shaped Conducting Structures using Triangular Meshes - Vikram J; Yong Wang; Dipanjan Gope; Richard Shi
The Partial-Element-Equivalent-Circuit (PEEC) approach is an effective method to convert three-dimensional on-chip multi-conductor structures to circuit-level descriptions. In this paper, a triangular-mesh-based PEEC approach is described, wherein the surfaces of arbitrarily-shaped conducting structures are represented by triangular mesh tesselations. A coupled EM-circuit formulation is obtained through the separation of the scalar, vector, and ohmic potential interactions between pairs of triangular edges-based basis functions. The overall approach can be interpreted as a SPICE-free, surface-only version of PEEC method and is especially useful for on-chip signal integrity analysis of systems-on-chip layout where components with irregular shapes are common.

17. [pt] INDUTOR NA HORIZONTAL - ANA MARIA BELTRAN PAVANI
[pt] A imagem contém um indutor desenhado na horizontal.

18. [pt] CAPACITOR NA HORIZONTAL - ANA MARIA BELTRAN PAVANI
[pt] A imagem contém um capacitor desenhado na horizontal.

19. [pt] RESISTOR NA HORIZONTAL - ANA MARIA BELTRAN PAVANI
[pt] A imagem contém um resistor desenhado na horizontal.

20. A Parallel Band-Matrix Solver for a Circuit Simulation Problem - Luís Miguel Silveira; Lu'is Miguel Silveira
This report sumarizes and evaluates an implementation of a general band-matrix solver algorithm on a massively parallel multiprocessor, the "Connection Machine". The band algorithm is used in a nonlinear relaxation-based circuit simulator for solving the system of equations associated with the node voltages, at each Newton iteration at each time step. Acknowledgments This report is part of the requisites for course 18.435/6.848, taught by Prof. F. Thomson Leighton at the Massachusetts Institute of Technology in the Fall Term of 1988. I thank Andrew Lumsdaine who wrote the original sequential version of the simulator and did most of the circuit element...

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