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Concept

Signal propagation delay

Publications associées (31)

Accretion Disk Size and Updated Time-delay Measurements in the Gravitationally Lensed Quasar SDSS J165043.44+425149.3

Frédéric Courbin, Martin Raoul Robert Millon

We analyze variability in 15-season optical lightcurves from the doubly imaged lensed quasar SDSS J165043.44+425149.3 (SDSS1650), comprising five seasons of monitoring data from the Maidanak Observatory (277 nights in total, including the two seasons of da ...

Iop Publishing Ltd2024

On Speed and Advantage : Results in Information Velocity and Monitoring Problems

Reka Inovan

Information theory has allowed us to determine the fundamental limit of various communication and algorithmic problems, e.g., the channel coding problem, the compression problem, and the hypothesis testing problem. In this work, we revisit the assumptions ...

EPFL2024

A Delay and Power Efficient Voltage Level Shifter with Low Leakage Power

Alexandre Schmid, Mehdi Saberi

This paper presents a new power-efficient and high-speed voltage level shifter. In the proposed structure, the existing contentions at the internal nodes are reduced using auxiliary transistors and feedback networks, leading to a significant reduction in t ...

IEEE2023

Simulating time-varying strong lenses

Georgios Vernardos

We present a self-consistent and versatile forward modelling software package that can produce time series and pixel-level simulations of time-varying strongly lensed systems. The time dimension, which needs to take into account different physical mechanis ...

OXFORD UNIV PRESS2022

The power of adaptivity in source identification with time queries on the path

Patrick Thiran, Gergely Odor

We study the problem of identifying the source of a stochastic diffusion process spreading on a graph based on the arrival times of the diffusion at a few queried nodes. In a graph

G=(V,E)

, an unknown source node

v^* \in V

is drawn uniformly at random, ...

2022

Time-delay estimation in unresolved lensed quasars

Georgios Vernardos

Time-delay cosmography can be used to infer the Hubble parameter H-0 by measuring the relative time delays between multiple images of gravitationally lensed quasars. A few of such systems have already been used to measure H-0: Their time delays were determ ...

OXFORD UNIV PRESS2022

Gravitational causality and the self-stress of photons

Brando Bellazzini

We study causality in gravitational systems beyond the classical limit. Using on-shell methods, we consider the 1-loop corrections from charged particles to the photon energy-momentum tensor - the self-stress - that controls the quantum interaction between ...

Springer Nature2022

TOCOSMO VIII. A key test of systematics in the hierarchical method of time-delay cosmography

Frédéric Courbin

The largest source of systematic errors in the time-delay cosmography method likely arises from the lens model mass distribution, where an inaccurate choice of model could in principle bias the value of H-0. A Bayesian hierarchical framework has been propo ...

EDP SCIENCES S A2022

The Universal Gossip Fighter

Rachid Guerraoui, Anne-Marie Kermarrec, Rafaël Benjamin Pinot, Anastasiia Kucherenko

The notion of adversary is a staple of distributed computing. An adversary typically models “hostile” assumptions about the underlying distributed environment, e.g., a network that can drop messages, an operating system that can delay processes or an attac ...

IEEE2022

Low Noise Clock Generation: Modeling, Analysis and Implementation

Duygu Kostak

The aim of this thesis is to implement, analyze and improve the selected low noise clock generation and distribution techniques for ADC implementations. The thesis is divided into two parts. The first part focuses on the sampling phase generation and distr ...

EPFL2021

A Correlation-Based Electromagnetic Time Reversal Technique to Locate Indoor Transient Radiation Sources

Farhad Rachidi-Haeri, Marcos Rubinstein, Zhaoyang Wang, Qi Li

To overcome the multipath interference in locating transient electromagnetic (EM) radiation sources in an indoor environment, we propose a criterion that calculates the correlation between back-propagated signals from observation points, to be used in EM t ...

Institute of Electrical and Electronics Engineers2021

TDCOSMO II. Six new time delays in lensed quasars from high-cadence monitoring at the MPIA 2.2m telescope

Sun Hee Kim, Frédéric Courbin, Hung-Hsu Chan, Vivien François Bonvin, Martin Raoul Robert Millon, Karina Alexandra Rojas Olate, Eric Gérard Guy Paic, Cameron Alexander Campbell Lemon

We present six new time-delay measurements obtained from Rc-band monitoring data acquired at the Max Planck Institute for Astrophysics (MPIA) 2.2m telescope at La Silla observatory between October 2016 and February 2020. The lensed quasars HE0047 1756, WG0 ...

EDP SCIENCES S A2020

COSMOGRAIL: XIX. Time delays in 18 strongly lensed quasars from 15 years of optical monitoring star

Frédéric Courbin, Georges Meylan, Hung-Hsu Chan, Vivien François Bonvin, Malte Tewes, Martin Raoul Robert Millon, Aymeric Alexandre Galan, Rémy Elie Joseph, Eric Gérard Guy Paic, Cameron Alexander Campbell Lemon, Olga Tihhonova

We present the results of 15 years of monitoring lensed quasars, which was conducted by the COSMOGRAIL programme at the Leonhard Euler 1.2 m Swiss Telescope. The decade-long light curves of 23 lensed systems are presented for the first time. We complement ...

EDP SCIENCES S A2020

The Upper Bound of the Speed of Propagation of Waves along a Transmission Line

Farhad Rachidi-Haeri, Marcos Rubinstein

According to theory, once certain conditions are fulfilled, current and voltage pulses propagate along ideal transmission lines with the speed of light. One can reach such a conclusion only when the conductors are assumed to be perfectly conducting, which ...

2020

Sensitivity to temporal parameters of intraneural tactile sensory feedback

Silvestro Micera, Stanisa Raspopovic, Ivo Strauss, Giacomo Valle, Francesco Maria Petrini, Edoardo D'Anna

Background Recent studies have shown that neural stimulation can be used to provide artificial sensory feedback to amputees eliciting sensations referred on the amputated hand. The temporal properties of the neural stimulation modulate aspects of evoked se ...

BioMed Central2020

Electromagnetic Fields Associated With the M‐Component Mode of Charge Transfer

Marcos Rubinstein, Mohammad Azadifar, Davide Pavanello, Lixia He

In upward flashes, charge transfer to ground largely takes place during the initial continuous current (ICC) and its superimposed pulses (ICC pulses). ICC pulses can be associated with either M-component or leader/return-stroke like modes of charge transfe ...

2019

Two-degrees-of-freedom (PID)-D-2 controller for precise nanopositioning in the presence of hardware-induced constant time delay

Andres San Millan Rodriguez

The fast and accurate tracking of periodic and arbitrary reference trajectories is the principal goal in many nanopositioning applications. Flexure-based piezoelectric stack driven nanopositioners are widely employed in applications where accurate mechanic ...

ELSEVIER SCIENCE INC2019

Modeling and integrated control of macroscopic heterogeneous traffic flow in large scale urban network using coloured Petri net

Nikolaos Geroliminis, Anastasios Kouvelas

The evaluation of perimeter control using Macroscopic Fundamental Diagram (MFD) concept is strongly related with the quality of the corresponding dynamic models. For capturing the real characteristics of traffic dynamics, an enhanced accumulation-based tra ...

2019

COSMOGRAIL XVIII. time delays of the quadruply lensed quasar WFI2033-4723

Sun Hee Kim, Frédéric Courbin, Georges Meylan, Hung-Hsu Chan, Vivien François Bonvin, Malte Tewes, Martin Raoul Robert Millon, Karina Alexandra Rojas Olate

We present new measurements of the time delays of WFI2033-4723. The data sets used in this work include 14 years of data taken at the 1.2 m Leonhard Euler Swiss telescope, 13 years of data from the SMARTS 1.3 m telescope at Las Campanas Observatory and a s ...

2019

Strongly lensed SNe Ia in the era of LSST: observing cadence for lens discoveries and time-delay measurements

Frédéric Courbin, Hung-Hsu Chan, Vivien François Bonvin

The upcoming Large Synoptic Survey Telescope (LSST) will detect many strongly lensed Type Ia supernovae (LSNe Ia) for time-delay cosmography. This will provide an independent and direct way for measuring the Hubble constant H0, which is necessary to addres ...

2019