Search results for "Circuits"
showing 10 items of 358 documents
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…
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…
Social Influence Maximization in Hypergraphs
2021
This work deals with a generalization of the minimum Target Set Selection (TSS) problem, a key algorithmic question in information diffusion research due to its potential commercial value. Firstly proposed by Kempe et al., the TSS problem is based on a linear threshold diffusion model defined on an input graph with node thresholds, quantifying the hardness to influence each node. The goal is to find the smaller set of items that can influence the whole network according to the diffusion model defined. This study generalizes the TSS problem on networks characterized by many-to-many relationships modeled via hypergraphs. Specifically, we introduce a linear threshold diffusion process on such …
Capacity and Energy-Consumption Optimization for the Cluster-Tree Topology in IEEE 802.15.4
2011
International audience; 802.15.4 proposes to use a cluster-tree hierar- chy to organize the transmissions in Wireless Sensor Networks. In this letter, we propose a framework to analyze formally the capacity and the energy consumption of this structure. We derive a Mixed Integer Linear Programming (MILP) formulation to obtain a topology compliant with the standard. This formulation provides the optimal solution for the network capacity: this con- stitutes an upper bound for any distributed algorithms permitting to construct a cluster-tree. This framework can also be used to evaluate the capacity and to compare quantitatively different cluster-tree algorithms.
Model Identification of a Network as Compressing Sensing
2013
In many applications, it is important to derive information about the topology and the internal connections of dynamical systems interacting together. Examples can be found in fields as diverse as Economics, Neuroscience and Biochemistry. The paper deals with the problem of deriving a descriptive model of a network, collecting the node outputs as time series with no use of a priori insight on the topology, and unveiling an unknown structure as the estimate of a "sparse Wiener filter". A geometric interpretation of the problem in a pre-Hilbert space for wide-sense stochastic processes is provided. We cast the problem as the optimization of a cost function where a set of parameters are used t…
Guided Surgery and Immediate Loading
2019
Computer-assisted implant dentistry can contribute for a better treatment planning, for the implementation of the implant placement, for capturing the intraoral situation, for processing data to design temporary and final prostheses, and for the manufacturing of prosthetic components.
Evaluation of an Alternative for Increasing Switch Radix
2011
In large switch-based interconnection networks, increasing the switch radix results in a decrease in the total number of network components. In this paper we evaluate an interesting strategy for building high-radix switches going beyond the integration scale bounds. This approach is independent of the evolution of single-chip switches and will remain valid as integration scale keeps evolving. Simulation results show that with a correct internal switch design, this kind of switches achieves almost the same performance as single-chip switches with the same radix, which would be unfeasible with current integration scale.
Advanced Monitoring Systems Based on Battery-Less Asset Tracking Modules Energized through RF Wireless Power Transfer
2020
Asset tracking involving accurate location and transportation data is highly suited to wireless sensor networks (WSNs) featuring battery-less nodes that can be deployed in virtually any environment and require little or no maintenance. In response to the growing demand for advanced battery-less sensor tag solutions, this article presents a system for identifying and monitoring the speeds of assets in a WSN with battery-less tags that receive all their operating energy through radio frequency (RF) wireless power transfer (WPT) architecture, and a unique measurement approach to generate time-domain speed readouts. The assessment includes performance characteristics and key features of a syste…
La distribution : organisation et stratégie
2020
Croissance rapide de nouvelles formes de vente, stratégies de mutualisation des ressources logistiques, phygitalisation, plateformisation, politique de réenchantement des points de vente... Autant de bouleversements du paysage économique qui font désormais de la distribution une fonction clé de la gestion des entreprises. Comprendre et expliquer à la fois sa dynamique et ses enjeux revêt, à ce titre, une importance majeure. Rédigé par trois spécialistes reconnus du sujet, l'ouvrage se fixe pour objectif d'aborder de façon pédagogique les principales dimensions de la distribution : la relation avec l'acheteur final, la gestion des interfaces entre industriels et distributeurs, et les enjeux …
Progress towards innovative and energy efficient logic circuits
2020
Abstract The integration of superconductive nanowire logic memories and energy efficient computing Josephson logic is explored. Nanowire memories are based on the integration of switchable superconducting nanowires with a suitable magnetic material. These memories exploit the electro-thermal operation of the nanowires to efficiently store and read a magnetic state. In order to achieve proper memory operation a careful design of the nanowire assembly is necessary, as well as a proper choice of the magnetic material to be employed. At present several new superconducting logic families have been proposed, all tending to minimize the effect of losses in the digital Josephson circuits replacing …