When a physical signal is received and used, it is most of the time noisy and not smooth. In order to manipulate it digitally, it is necessary to convert it into a smooth signal, or regularize it. A classical ways to do so is to convolve the signal with a Gaussian of fixed variance, which determines the scale at which the signal can be considered smooth. In many situations, signals are not uniformly noisy, and some parts show important local defects, while the global signal is acceptable.
A compressible Hybrid Lattice Boltzmann Method solver is used to perform a wall-resolved Large eddy simulation of an isothermal axisymmetric jet issuing from a pipe and impinging on a heated flat plate at a Reynolds number of 23 000, a Mach number of 0.1, and an impingement distance of two jet diameters. The jet flow field statistics, Nusselt number profile (including the secondary peak), and shear stress profile were well reproduced.
The interest rate at which US firms borrow funds has two features: (i) it moves in a countercyclical fashion and (ii) it is an inverted leading indicator of real economic activity: low interest rates today forecast future booms in GDP, consumption, investment, and employment.
Belgian and Swiss media regularly interfere during French elections by releasing exit polls before polling stations close. These foreign media profit from a law forbidding the same behavior by their French counterparts to receive large inflows of web visits from France. We exploit the unusual timing and degree of confidence with which exit polls were released in the second round of the 2017 presidential elections to investigate their effect on voter turnout.
Soon after the onset of the COVID-19 pandemic, the French government decided to still hold the first round of the 2020 municipal elections as scheduled on March 15. What was the impact of these elections on the spread of COVID-19 in France? Answering this question leads to intricate econometric issues as omitted variables may drive both epidemiological dynamics and electoral turnout, and as a national lockdown was imposed at almost the same time as the elections.
Corruption is a barrier to entrepreneurship in emerging countries, justifying to investigate its determinants. Using data on 1,250 entrepreneurs across Indonesian regions, We analyze the effects of social capital on individual corruption. 2-levels ordered probit regressions evidence that weak-ties discourage entrepreneurs’ bribing, strong-ties encourage it, whereas this latter effect is moderated by the quality of access to formal credit.
We present an inexact proximal point algorithm using quasi distances to solve a minimization problem in the Euclidean space. This algorithm is motivated by the proximal methods introduced by Attouch et al., section 4, (Math Program Ser A, 137: 91–129, 2013) and Solodov and Svaiter (Set Valued Anal 7:323–345, 1999).
Large-scale analyses to map interactions between financial health at the sectoral level are still scarce. To fill the gap, in this paper, I map a network of predictive relationships across the financial health of several sectors. I provide a new advanced indicator to track propagation of financial distress across industries and countries on a monthly basis. I use defaults on trade credit as a measure of firms' worsening financial conditions in a sector.
This paper deals with the modeling of non-stationary signals, from the point of view of signal synthesis. A class of random, non-stationary signals, generated by synthesis from a random timescale representation, is introduced and studied. Non-stationarity is implemented in the timescale representation through a prior distribution which models the action of time warping on a stationary signal.