Adaptive Diagnosis for Fault Tolerant Data Fusion Based on α-Rényi Divergence Strategy for Vehicle Localization

When applying a diagnostic technique to complex systems, whose dynamics, constraints, and environment evolve over time, being able to re-evaluate the residuals that are capable of detecting defaults and proposing the most appropriate ones can quickly prove to make sense. For this purpose, the concept of adaptive diagnosis is introduced. In this work, the contributions of information theory are investigated in order to propose a Fault-Tolerant multi-sensor data fusion framework. This work is part of studies proposing an architecture combining a stochastic filter for state estimation with a diagnostic layer with the aim of proposing a safe and accurate state estimation from potentially inconsistent or erroneous sensors measurements. From the design of the residuals, using α-Rényi Divergence (α-RD), to the optimization of the decision threshold, through the establishment of a function that is dedicated to the choice of α at each moment, we detail each step of the proposed automated decision-support framework. We also dwell on: (1) the consequences of the degree of freedom provided by this α parameter and on (2) the application-dictated policy to design the α tuning function playing on the overall performance of the system (detection rate, false alarms, and missed detection rates). Finally, we present a real application case on which this framework has been tested. The problem of multi-sensor localization, integrating sensors whose operating range is variable according to the environment crossed, is a case study to illustrate the contributions of such an approach and show the performance.     

Structure,dielectric and optical properties of p-type (PVA/CuI) nanocomposite polymer electrolyte for photovoltaic cells

A novel PVA/CuI nanocomposite polymer electrolyte layer synthesized via the reduction of CuCl₂ by NaI in an aqueous PVA solution. The as-prepared films were characterized by X-ray diffraction, scanning electron microscope, as well as impedance spectroscopy. The obtained results indicated the formation of hexagonal CuI nano particles of ≈55 nm sizes embedded in the PVA matrix. In addition, the study of dielectric parameters and conductivity of PVA/CuI nanocomposite in wide range of temperature and frequency are given and discussed. The frequency dependence of ac-conductivity suggests power law with an exponent 0.026 < s < 0.73 which predicts hopping of charge carriers. The bulk conductivity showed activation with temperature, significant values of activation energy are deduced and discussed. An average value of the energy gap width, 2.05 eV obtained using optical absorption in UV–visible spectra for PVA/CuI nanocomposite polymer electrolyte.     

On the specific heat jump at Tc of the V3Si crystals

Parameters deduced from new specific heat measurements on transforming V₃Si single crystals are compared with those previously given for non transforming samples within the microscopic electronic model of Labbé-Friedel. As a result, a new approach to the martensitic transition is suggested to explain the discrepancy relative to the above parameter which differentiates the two classes of V₃Si samples.     

Sunscreens Containing Cyclodextrin Inclusion Complexes for Enhanced Efficiency: A Strategy for Skin Cancer Prevention

Unprotected exposure of skin to solar ultraviolet radiation (UVR) may damage the DNA of skin cells and can lead to skin cancer. Sunscreens are topical formulations used to protect skin against UVR. The active ingredients of sunscreens are UV filters that absorb, scatter, and/or reflect UVR. Preventing the formation of free radicals and repairing DNA damages, natural antioxidants are also added to sunscreens as a second fold of protection against UVR. Antioxidants can help stabilise these formulations during the manufacturing process and upon application on skin. However, UV filters and antioxidants are both susceptible to degradation upon exposure to sunlight and oxygen. Additionally, due to their poor water solubility, natural antioxidants are challenging to formulate and exhibit limited penetration and bioavailability in the site of action (i.e., deeper skin layers). Cyclodextrins (CDs) are cyclic oligosaccharides that are capable of forming inclusion complexes with poorly soluble drugs, such as antioxidants. In this review, we discuss the use of CDs inclusion complexes to enhance the aqueous solubility of antioxidants and chemical UV filters and provide a protective shield against degradative factors. The role of CDs in providing a controlled drug release profile from sunscreens is also discussed. Finally, incorporating CDs inclusion complexes into sunscreens has the potential to increase their efficiency and hence improve their skin cancer prevention.     

Radiation Dosimetry of some New Dyes Containing 2-Thiohydantoin Nucleus

A number of 5-arylazo-2-thiohydantoins (Ia … e) were prepared. The structure of the prepared materials is established by means of correct analytical data, infrared and electronic absorption spectra. Then the materials were subjected to an absorbed energetic γ-ray dose (5.0 × 10⁷ rd). The infrared and electronic absorption spectra of each material were measured after γ-irradiation. Upon γ-irradiation a considerable change occurs. Furthermore a sequence for the relative stability of the different dyes against γ-irradiation was established.

Eine Anzahl von 5-arylazo-2-thiohydanloine (la … e) wurde synthetisiert und ihre Struktur neben der analytischen Zusammensetzung durch Infrarot- und Elektronenabsorptionsspektren gesichert. Diese Substanzen wurden einer energiereichen γ-Strahlung (5 · 10⁷ rad) unlerworfen und die IR- und UV/VIS-Speklren nach der γ-Bestrahlung wieder aufgenommen. Bei einigen Substanzen wurden bemerkenswerte Veränderungen beobachtet, andere zeigten gegenüber der γ-Strahlung eine relative Stabililät.     

The superconducting transition and the behavior of the ac susceptibility

The ac susceptibility behavior of superconductors close to the superconducting transition temperature is explained on the basis of the BCS theory. Previous approaches to this problem were based on the average conductivity model, the London and the two-fluid models. It is shown that they are not able to explain the observed χPrime;-peak at T_c and are basically, not adequate for the treatment of such a problem.