Image denoising with multi-layer perceptrons, part 1: comparison with existing algorithms and with bounds

Image denoising can be described as the problem of mapping from a noisy image to a noise-free image. The best currently available denoising methods approximate this mapping with cleverly engineered algorithms. In this work we attempt to learn this mapping directly with plain multi layer perceptrons (MLP) applied to image patches. We will show that by training on large image databases we are able to outperform the current state-of-the-art image denoising methods. In addition, our method achieves results that are superior to one type of theoretical bound and goes a large way toward closing the gap with a second type of theoretical bound. Our approach is easily adapted to less extensively studied types of noise, such as mixed Poisson-Gaussian noise, JPEG artifacts, salt-and-pepper noise and noise resembling stripes, for which we achieve excellent results as well. We will show that combining a block-matching procedure with MLPs can further improve the results on certain images. In a second paper, we detail the training trade-offs and the inner mechanisms of our MLPs

Money stock control and its implications for monetary policy

Monetary policy ; Money supply

Are Your Explanations Reliable? Investigating the Stability of LIME in Explaining Text Classifiers by Marrying XAI and Adversarial Attack

LIME has emerged as one of the most commonly referenced tools in explainable AI (XAI) frameworks that is integrated into critical machine learning applications--e.g., healthcare and finance. However, its stability remains little explored, especially in the context of text data, due to the unique text-space constraints. To address these challenges, in this paper, we first evaluate the inherent instability of LIME on text data to establish a baseline, and then propose a novel algorithm XAIFooler to perturb text inputs and manipulate explanations that casts investigation on the stability of LIME as a text perturbation optimization problem. XAIFooler conforms to the constraints to preserve text semantics and original prediction with small perturbations, and introduces Rank-biased Overlap (RBO) as a key part to guide the optimization of XAIFooler that satisfies all the requirements for explanation similarity measure. Extensive experiments on real-world text datasets demonstrate that XAIFooler significantly outperforms all baselines by large margins in its ability to manipulate LIME's explanations with high semantic preservability.Comment: 14 pages, 6 figures. Replacement by the updated version to be published in EMNLP 202

Pseudo-Critical Temperature and Thermal Equation of State from Nf = 2 Twisted Mass Lattice QCD

We report about the current status of our ongoing study of the chiral limit of two-flavor QCD at finite temperature with twisted mass quarks. We estimate the pseudo-critical temperature Tc for three values of the pion mass in the range of mPS ~ 300 and 500 MeV and discuss different chiral scenarios. Furthermore, we present first preliminary results for the trace anomaly, pressure and energy density. We have studied several discretizations of Euclidean time up to Nt = 12 in order to assess the continuum limit of the trace anomaly. From its interpolation we evaluate the pressure and energy density employing the integral method. Here, we have focussed on two pion masses with mPS ~ 400 and 700 MeV

Baseline and triangulation geometry in a standard plenoptic camera

In this paper, we demonstrate light field triangulation to determine depth distances and baselines in a plenoptic camera. The advancement of micro lenses and image sensors enabled plenoptic cameras to capture a scene from different viewpoints with sufficient spatial resolution. While object distances can be inferred from disparities in a stereo viewpoint pair using triangulation, this concept remains ambiguous when applied in case of plenoptic cameras. We present a geometrical light field model allowing the triangulation to be applied to a plenoptic camera in order to predict object distances or to specify baselines as desired. It is shown that distance estimates from our novel method match those of real objects placed in front of the camera. Additional benchmark tests with an optical design software further validate the model’s accuracy with deviations of less than 0:33 % for several main lens types and focus settings. A variety of applications in the automotive and robotics field can benefit from this estimation model

The thermal QCD transition with two flavours of twisted mass fermions

We investigate the thermal QCD transition with two flavors of maximally twisted mass fermions for a set of pion masses, 300 MeV \textless $m_\pi$ \textless 500 MeV, and lattice spacings $a$ \textless 0.09 fm. We determine the pseudo-critical temperatures and discuss their extrapolation to the chiral limit using scaling forms for different universality classes, as well as the scaling form for the magnetic equation of state. For all pion masses considered we find resonable consistency with O(4) scaling plus leading corrections. However, a true distinction between the O(4) scenario and a first order scenario in the chiral limit requires lighter pions than are currently in use in simulations of Wilson fermions.Comment: 11 pages, 11 figure

Nighttime resident supervision and education: results of a national survey of internal medicine residency program directors

Over the past several years, the Accreditation Council for Graduate Medical Education (ACGME) has issued new restrictions on resident duty hours while calling for increased supervision to ensure patient safety. To meet these requirements, some hospitals have hired overnight in-house hospitalist physicians, also called nocturnists, while others have continued a traditional model wherein a resident in-house can access a supervisor at home by phone as needed. This study examines the current state of internal medicine resident supervision and teaching at night.Christopher Bruti (Rush University Medical Center), Mathhew Tuck (Veterans Affairs Medical Center), Rebecca Harrison (Oregon Health and Science University School of Medicine), Dustin Smith (Atlanta VA Medical Center), Michael Kisielewski (Alliance for Academic Internal Medicine), Jillian S. Catalanotti (The George Washington University School of Medicine and Health Sciences), Alfred Burger (Icahn School of Medicine)Includes bibliographical reference