RFId systems for moveable asset management: an assessment model

Management of moveable assets is a key issue in most industrial manufacturing companies. With the increasing complexity of production systems characterised by numerous and heterogeneous machining centres, it becomes quite hard to carry out an effective and cost-efficient management model of the tools and fixtures needed for ensuring a correct and timely execution of the planned production cycles. A prerequisite for a proper management of moveable assets is the adoption of identification systems to support the traceability and data collection of the most relevant pieces of information along the life cycle of an asset. The aim of this paper was to provide an assessment model for evaluating the benefits and costs related to the adoption of RFId tags as identifications systems for moveable assets, and in particular in managing machinery tools in a production premise. In order to present a practical example of applicability of the model, an industrial application is reported with an in-depth analysis of the potential benefits and issues derived from the implementation of RFId tags.     

The complexity of constructing pseudorandom generators from hard functions

We study the complexity of constructing pseudorandom generators (PRGs) from hard functions, focussing on constant-depth circuits. We show that, starting from a function computable in alternating time O(l) with O(1) alternations that is hard on average (i.e. there is a constant such that every circuit of size fails to compute f on at least a 1/poly(l) fraction of inputs) we can construct a computable by DLOGTIME-uniform constant-depth circuits of size polynomial in n. Such a PRG implies under DLOGTIME-uniformity. On the negative side, we prove that starting from a worst-case hard function (i.e. there is a constant such that every circuit of size fails to compute f on some input) for every positive constant there is no black-box construction of a computable by constant-depth circuits of size polynomial in n. We also study worst-case hardness amplification, which is the related problem of producing an average-case hard function starting from a worst-case hard one. In particular, we deduce that there is no blackbox worst-case hardness amplification within the polynomial time hierarchy. These negative results are obtained by showing that polynomialsize constant-depth circuits cannot compute good extractors and listdecodable codes.     

Generalized matrix method for calculation of internal light energy flux in mixed coherent and incoherent multilayers

A generalized matrix method to treat multilayer systems with mixed coherent and incoherent optical behavior is presented. The method is based on the calculation of the light energy flux inside the multilayer, whose internal light absorption is straightforwardly derived. The Poynting vector is used to derive the light energy flux in the case of a layer with coherent behavior. Multilayer structures with any distribution of layers with coherent or incoherent behavior can be treated, including the case of oblique incidence. Use of the light energy flux instead of the more commonly used light intensity permits the calculation of light absorption with a better accuracy and a much shorter computation time.     

Nanosized Pt-perovskite catalyst for the regeneration of a wall-flow filter for soot removal from diesel exhaust gases

Topics in Catalysis - Perovskite-type catalysts have been investigated for diesel soot combustion: (i) the LaCr0.9O3?δ substoichiometric perovskite, (ii) K–La partially substituted...     

FODMAP modulation as a dietary therapy for IBS: Scientific and market perspective

A diet low in fermentable oligosaccharides, disaccharides, monosaccharides, and polyols (FODMAPs) is a promising therapeutic approach to reduce gastrointestinal symptoms associated with irritable bowel syndrome (IBS). However, a shift toward a more sustainable, healthy diet with higher inclusion of whole-grain cereals (i.e., wheat, rye, barley) and pulses, naturally rich in FODMAPs, poses a severe challenge for susceptible individuals. Dietary restriction of fermentable carbohydrates (commonly called the “low FODMAP diet”) has received significant consideration. Hence, the development of functional low FODMAP products is emerging in food science and the food industry. In this review, we evaluate the most promising yet neglected (bio)-technological strategies adopted for modulating the FODMAP contents in complex food systems and the extent of their uptake in the global food market. We extensively investigated the global low FODMAP market, contrasted with the status quo in food science and discussed the key principles and concomitant challenges of targeted FODMAP reduction strategies. Powerful tools are available which are based either on the use of ingredients where FODMAPs have been physically removed (e.g., by membrane filtration) or biotechnologically reduced during the food processing, mediated by added enzymes, microbial enzymes during a fermentation process, and seed endogenous enzymes. However, <10% of the small market of functional products with a low FODMAP claim (total ∼800 products) used any of the targeted FODMAP reduction techniques. The global market is currently dominated by gluten-free products, which are naturally low in FODMAPs and characterized by inferior sensory attributes.     

Mutations Causing Mild or No Structural Damage in Interfaces of Multimerization of the Fibrinogen γ-Module More Likely Confer Negative Dominant Behaviors

Different pathogenic variants in the same protein or even within the same domain of a protein may differ in their patterns of disease inheritance, with some of the variants behaving as negative dominant and others as autosomal recessive mutations. Here is presented a structural analysis and comparison of the molecular characteristics of the sites in fibrinogen γ-module, a fibrinogen component critical in multimerization processes, targeted by pathogenic variants (HGMD database) and by variants found in the healthy population (gnomAD database). The main result of this study is the identification of the molecular pathogenic mechanisms defining which pattern of disease inheritance is selected by mutations at the crossroad of autosomal recessive and negative dominant modalities. The observations in this analysis also warn about the possibility that several variants reported in the non-pathogenic gnomAD database might indeed be a hidden source of diseases with autosomal recessive inheritance or requiring a combination with other disease-causing mutations. Disease presentation might remain mostly unrevealed simply because the very low variant frequency rarely results in biallelic pathogenic mutations or the coupling with mutations in other genes contributing to the same disease. The results here presented provide hints for a deeper search of pathogenic mechanisms and modalities of disease inheritance for protein mutants participating in multimerization phenomena.     

Deposition Uniformity of Coal Dust on Filters and Its Effect on the Accuracy of FTIR Analyses for Silica

Miners are exposed to silica-bearing dust which can lead to silicosis, a potentially fatal lung disease. Currently, airborne silica is measured by collecting filter samples and sending them to a laboratory for analysis. Since this may take weeks, a field method is needed to inform decisions aimed at reducing exposures. This study investigates a field-portable Fourier transform infrared (FTIR) method for end-of-shift (EOS) measurement of silica on filter samples. Since the method entails localized analyses, spatial uniformity of dust deposition can affect accuracy and repeatability. The study, therefore, assesses the influence of radial deposition uniformity on the accuracy of the method. Using laboratory-generated Minusil and coal dusts and three different types of sampling systems, multiple sets of filter samples were prepared. All samples were collected in pairs to create parallel sets for training and validation. Silica was measured by FTIR at nine locations across the face of each filter and the data analyzed using a multiple regression analysis technique that compared various models for predicting silica mass on the filters using different numbers of “analysis shots.” It was shown that deposition uniformity is independent of particle type (kaolin vs. silica), which suggests the role of aerodynamic separation is negligible. Results also reflected the correlation between the location and number of shots versus the predictive accuracy of the models. The coefficient of variation (CV) for the models when predicting mass of validation samples was 4%–51% depending on the number of points analyzed and the type of sampler used, which affected the uniformity of radial deposition on the filters. It was shown that using a single shot at the center of the filter yielded predictivity adequate for a field method, (93% return, CV approximately 15%) for samples collected with 3-piece cassettes.

Copyright 2013 American Association for Aerosol Research     

Quality,distance and trade: A strategic approach

This paper contributes to the literature on distance and quality by identifying a firm‐based force contributing to explain the observed increase of the quality of shipped goods with the distance of their destination market. This force originates from the influence of distance on firms' strategic behaviour in the presence of consumer heterogeneity, when the quality level of goods is a choice variable for them. Our approach differs from the extant literature because it does not rely on technology or preference/income differentials to identify the determinants and drivers of trade flows. We find that distance has an unambiguously positive effect on the average quality of traded goods. Our results contribute to the analysis of the determinants of firms' trade performance.     

Mechanical Properties of Phosphate Glass Optical Fibers

In this work, step-index 40/125 μm diameter optical fibers produced from two slightly different lithium phosphate glasses were subjected to mechanical characterization. Tensile tests were carried out on fibers with gage length from 10 to 150 mm, allowing for the determination of the failure stress (ranging from ≈200 to 400 MPa) and the elastic modulus (60 GPa). Some tests were also performed with the fiber “immersed” in water; an important subcritical crack growth effect was pointed out, and a fatigue susceptibility parameter (n) equal to 11.4 was determined. The analysis of fracture mirror allows an estimated fracture toughness equal to 0.5 MPa m^0.5.     

A circuit model of an ultra wideband impulse radar system for breath‐activity monitoring

The aim of this work is to present a circuit model to analyze and design ultra wideband (UWB) radars for the remote monitoring of breath activity. The model includes the impulse signal source, the transceiver antenna, the transmission medium, and the human thorax. First of all, the proposed model has been validated by comparing its responses with those achieved both numerically, with a commercial electromagnetic modeling software, and experimentally, by means of a setup based on an indirect time domain reflectometry system. Then, the model has been used for analyzing the feasibility of a UWB radar operating in the 3–6‐GHz range with an effective isotropic radiated power lower than − 41.3 dBm/MHz, i.e. within the limits issued by the United States Federal Communications Commission for unlicensed UWB imaging systems. The model outlined the possibility of the considered UWB radar of monitoring the breath activity of a subject up to distances of about 10 m in open air. Copyright © 2011 John Wiley & Sons, Ltd.