Search results for "CIRCUIT"

An Improved Approach to the Simulation of Single-Line-to-Ground Faults in Transmission Networks

2009

These paper presents a mathematical model for studying the Single-Line-to-Ground fault in transmission networks, giving a personal contribution for a methodical and accurate analysis of complex systems, by providing an evolution of the “circuital method” able to solve the case of a system in which more than one line supply the fault.

Joint User Association and Dynamic Beam Operation for High Latitude Muti-beam LEO Satellites

2021

In Low Earth Orbit (LEO) satellites, which run in polar orbit, the area of overlap among beams becomes wider as the latitude of satellites increases, which leads to intolerable interference and extra energy consumption. To minimize the onboard power with QoS requirements, we propose an energy optimization model with considering power allocation, user association and dynamic beam ON/OFF operation jointly. Moreover, the frequent beam ON/OFF operations lead to the large number of user handovers, so handover cost is also considered in the model. The original problem is decomposed into two levels due to the high coupling of variables and the successive convex approximation is employed. A low com…

Hot Impression Die Forging Process: An Approach to Flash Design for Tool Life Improvement

2005

In impression die forging the role of the flash geometry is fundamental since a proper design of the flash land strongly influences both the complete die filling and the die wear (i.e. the die life and the related costs). In this paper an integrated approach between numerical simulations and statistical tools was developed with the aim to optimize flash thickness in order to reduce die wear and to minimize material wasting. As wear is regarded, an analytical model depending on sliding velocity, temperature, die hardness and contact pressure was utilized during the numerical simulations of the process in order to reach a wear evaluation for different values of the flash design variables. Thu…

uMemristorToolbox: Open source framework to control memristors in Unity for ternary applications

2020

This paper presents uMemristorToolbox, a novel open source framework that reads and writes non-volatile ternary states to memristors. The Unity (C#) framework is a port of the open source Java project Memristor-Discovery and adds a closed-loop ternary memory controller to enable both PC and real-time embedded ternary applications. We validate the closed-loop ternary memory controller in an embedded system case study with 16 M+SDC Tungsten dopant memristors. We measure an average switching speed of 3 Hz, worst case energy usage of 1 μW per switch, 0.03% random write error and no decay in (non-volatile) state retention after 15 minutes. We conclude with observations and open questions when wo…

Pasajes de París / 8: Su herencia

2006

Homodyne Solid-State Biased Coherent Detection of Ultra-Broadband Terahertz Pulses with Static Electric Fields.

2021

We present an innovative implementation of the solid-state-biased coherent detection (SSBCD) technique, which we have recently introduced for the reconstruction of both amplitude and phase of ultra-broadband terahertz pulses. In our previous works, the SSBCD method has been operated via a heterodyne scheme, which involves demanding square-wave voltage amplifiers, phase-locked to the THz pulse train, as well as an electronic circuit for the demodulation of the readout signal. Here, we demonstrate that the SSBCD technique can be operated via a very simple homodyne scheme, exploiting plain static bias voltages. We show that the homodyne SSBCD signal turns into a bipolar transient when the stat…

Optimal estimation of losses at the ultimate quantum limit with non-Gaussian states

2009

We address the estimation of the loss parameter of a bosonic channel probed by arbitrary signals. Unlike the optimal Gaussian probes, which can attain the ultimate bound on precision asymptotically either for very small or very large losses, we prove that Fock states at any fixed photon number saturate the bound unconditionally for any value of the loss. In the relevant regime of low-energy probes, we demonstrate that superpositions of the first low-lying Fock states yield an absolute improvement over any Gaussian probe. Such few-photon states can be recast quite generally as truncations of de-Gaussified photon-subtracted states.

Dynamic Modeling and Driving Cycle Prediction for a Racing Series Hybrid Car

2014

International audience; This paper presents Noao, a plug-in series hybrid racing car equipped with an engine/generator set as range extender. To determine the velocity profile, i.e., performance of the car and its power profile, a dynamic model for this car is developed using pedal position as input. This value is easy to measure, representative for race cycles, and presents a novelty. The model is validated with the results from experiments. An analysis based on the map of Magny-Cours racing circuit and drivers pedal action on certain zones of the circuit is formulated and is used as a prediction tool to determine drivers inputs on other racing circuits and generate driving schedules. The …

On the Energy Efficiency of Dual Prime Mover Pump-Controlled Hydraulic Cylinders

2019

Abstract This paper concerns the energy efficiency of a special class of pump-controlled hydraulic cylinders utilizing two prime movers. The performance of such circuits has been studied previously motivated by their capability of providing an actuator stiffness similar to that of servo valve-controlled systems. This characteristic may improve performance and robustness in applications requiring feedback control. In this paper, the presence of losses similar to that of fluid throttling, in the sense that they occur even in the absence of component inefficiencies, are demonstrated for such circuits and shown to degrade the overall energy efficiency of the system. The conditions under which s…

Neutron-Induced Effects on a Self-Refresh DRAM

2022

International audience; The field of radiation effects in electronics research includes unknowns for every new device, node size, and technical development. In this study, static and dynamic test methods were used to define the response of a self-refresh DRAM under neutron irradiation. The neutron-induced effects were investigated and characterised by event cross sections, soft-error rate, and bitmaps evaluations, leading to an identification of permanent and temporary stuck cells, single-bit upsets, and block errors. Block errors were identified in different patterns with dependency in the addressing order, leading to up to two thousand faulty words per event, representing a real threat fr…