Constraints on the CKM Matrix

We update the analyses of the Cabibbo-Kobayashi-Maskawa matrix, both within the Standard Model and for arbitrary New Physics contributions to the mixing amplitudes, using new inputs from the Winter 2006 conferences.Comment: Invited talk given at the FPCP 2006 conference (April 9-12), Vancouver, Canada. 10 pages, 8 figures. Legend of NP plots correcte

Status of the CKM Matrix and a simple New Physics scenario

Proceedings of the Second Workshop on Theory, Phenomenology and Experiments in Heavy Flavour Physics, June 16-18 2008, Capri (Italy)International audienceWe present a short status of the CKM matrix in the Standard Model as well as possible New Physics contributions to BBbar mixing

French Translation and Validation of Three Scales Evaluating Stigma in Mental Health

Objective: The concept of stigma refers to problems of knowledge (ignorance), attitudes (prejudice) and behavior (discrimination). Stigma may hinder access to care, housing and work. In the context of implementation of programs such as “housing first” or “individual placement and support” in French speaking regions, validated instruments measuring stigma are necessary. “Attitudes to Mental Illness 2011” is a questionnaire that includes three scales measuring stigma through these three dimensions. This study aimed to translate, adapt and validate these three scales in French. Methods: The “Attitudes to Mental Illness 2011” questionnaire was translated into French and back-translated into English by an expert. Two hundred and sixty-eight nursing students completed the questionnaire. Content validity, face validity, internal validity and convergent validity were assessed. Long-term reliability was also estimated over a three-month period. Results: Experts and participants found that the questionnaire’s content validity and face validity were appropriate. The internal validities of the three scales were also considered adequate. Convergent validity indicated that the scales did indeed measure what they were supposed to. Long-term stability estimates were moderate; this pattern of results suggested that the construct targeted by the three scales is adequately measured but does not necessarily represent stable and enduring traits. Conclusions: Because of their good psychometric properties, these three scales can be used in French, either separately, to measure one specific dimension of stigma, or together, to assess stigma in its three dimensions. This would seem of paramount importance in evaluating campaigns against stigma since it allows measures to be adapted according to campaign goals and the target population

BATUD: Blind Atmospheric TUrbulence Deconvolution

A new blind image deconvolution technique is developed for atmospheric turbulence deblurring. The originality of the proposed approach relies on an actual physical model, known as the Fried kernel, that quantifies the impact of the atmospheric turbulence on the optical resolution of images. While the original expression of the Fried kernel can seem cumbersome at first sight, we show that it can be reparameterized in a much simpler form. This simple expression allows us to efficiently embed this kernel in the proposed Blind Atmospheric TUrbulence Deconvolution (BATUD) algorithm. BATUD is an iterative algorithm that alternately performs deconvolution and estimates the Fried kernel by jointly relying on a Gaussian Mixture Model prior of natural image patches and controlling for the square Euclidean norm of the Fried kernel. Numerical experiments show that our proposed blind deconvolution algorithm behaves well in different simulated turbulence scenarios, as well as on real images. Not only BATUD outperforms state-of-the-art approaches used in atmospheric turbulence deconvolution in terms of image quality metrics, but is also faster

The Generalized Graetz Problem in Finite Domains

We consider the generalized Graetz problem associated with stationary convection-diffusion inside a domain having any regular three-dimensional translationally invariant section and finite or semi-infinite extent. Our framework encompasses any previous “extended” and “conjugated” Graetz generalizations and provides theoretical bases for computing the orthogonal set of generalized two-dimensional Graetz modes. The theoretical framework includes both heterogeneous and possibly anisotropic diffusion tensors. In the case of semi-infinite domains, the existence of a bounded solution is shown from the analysis of two-dimensional operator eigenvectors which form a basis of L2 . In the case of finite domains a similar basis can be exhibited, and the mode’s amplitudes can be obtained from the inversion of newly defined finite domain operator. Our analysis includes both the theoretical and practical issues associated with this finite domain operator inversion as well as its interpretation as a multireflection image method. Error estimates are provided when numerically truncating the spectrum to a finite number of modes. Numerical examples are validated for reference configurations and provided in nontrivial cases. Our methodology shows how to map the solution of stationary convection-diffusion problems in finite three-dimensional domains into a two-dimensional operator spectrum, which leads to a drastic reduction in computational cost

Gain and phase calibration of sensor arrays from ambient noise by cross-spectral measurements fitting

We address the problem of blind gain and phase calibration of a sensor array from ambient noise. The key motivation is to ease the calibration process by avoiding a complex procedure setup. We show that computing the sample covariance matrix in a diffuse field is sufficient to recover the complex gains. To do so, we formulate a non-convex least-square problem based on sample and model covariances. We propose to obtain a solution by low-rank matrix approximation, and two efficient proximal algorithms are derived accordingly. The first one solves the problem modified with a convex relaxation to guarantee that the solution is a global minimizer, and the second one directly solves the initial non-convex problem. We investigate the efficiency of the proposed algorithms by both numerical and experimental results according to different sensing configurations. These show that efficient calibration highly depends on how the measurements are correlated. That is, estimation is achieved more accurately when the field is spatially over-sampled.Comment: submitted to the Journal of the Acoustical Society of Americ

Centrifugal casting of glass plates: a finite-element analysis of process parameter influence

For the first time, glass centrifugal casting is analyzed by finite-element viscoplastic models. First of all, the sensitivity of the process parameters is analyzed on the radius lengthening of a glass gob during casting using central processing unit time-saving models. The suitability of glass for centrifuging is evaluated, taking its temperature, viscosity, mould rotation speed and time dependency, casting time and initial gob shape into account. A refined finite-element analysis of an NBS-710 plate production is then achieved. The results are used in decision-aid process design curves which allow the manufacturer to efficiently adjust process parameters with regard to the desired final shape

Corrosion Protection of Magnesium Alloys: From Chromium VI Process to Alternative Coatings Technologies

Magnesium and its alloys present several advantages such as a high strength/weight ratio and a low density. These properties allow them to be used for many aeronautical applications but they are very sensitive to corrosion. In order to solve this problem, chromium VI conversion coatings (CCC) are deposited on the surface before a protective top coat application. This process is now limited by several environmental laws due to the high toxicity of hexavalent chromium. However the chemical mechanisms of CCC deposition will be detailed in this chapter in order to understand the chemical properties of this coating. Pre-treatment steps allow cleaning and preparing the surface for improving the coating deposition. A final layer of chromium (III) oxide and magnesium hydroxide composes the coating allowing the protective properties. Orthorhombic potassium chromate clusters trapped on the coating surface give self-healing property to the coating. Alternative conversion coatings are based onto solutions containing chromium (III), permanganate, phosphates, Rare Earth Elements (REEs) or vanadium. The second part of this chapter will detail the deposition and the protection mechanisms of these promising processes of CrVI substitution. Among them, permanganate/phosphate-based coating presents a better corrosion resistance than CCC and REEs have very efficient self-healing properties