Single phase 1-kVA amorphous core transformer: design, experimentaltests, and performance after annealing

The design and experimental implementation of a single-phase power transformer operating at 1 kVA, 110/220 V, and 60 Hz, with an amorphous alloy core are described. The prototype core material is annealed in an argon atmosphere, under a DC magnetic field applied along the ribbon length. The experimental results are presented to compare the amorphous core transformer performance with another transformer with the same rated power, but with a silicon steel core     

Formal specification of beliefs in multi-agent systems

The goal of this paper is to present a logical framework for the formalization of agents' mutual beliefs in a Multi Agent system. The approach is based on a combination of extensional specifications of beliefs and context-based (finite) presentation of the specifications by employing a particular class of Multi Context systems. The extensional specification provides a set-theoretic characterization of beliefs in terms of sets closed under certain conditions. Its finite presentation is provided by using as constructors inference rules inside a Multi Context system. The resulting framework allows for capturing many relevant cases of real (not omniscient) agents, which are very common in Multi Agent scenarios embedded in real world environments. In order to substantiate this claim, two Multi Agent scenarios are formally specified in detail in the specification framework. ©1999 John Wiley & Sons, Inc.     

Effect of extraction systems on the phenolic composition of virgin olive oils

The effect of extraction systems on the phenolic composition of virgin olive oils obtained from two different Italian cultivars (Coratina and Oliarola) was determined. The oils extracted using two-phase centrifugation showed in all cases higher phenolic concentration in comparison to oils obtained from three-phase centrifugation. In particular, the highest differences were observed for aglykone derivatives of oleuropein (3,4-DHPEA-EDA and 3,4-DHPEA-EA) that are the most concentrated antioxidant phenolic compounds of virgin olive oil. These results were confirmed by the autoxidation stability of the oils examined.     

In situ optical control and stabilization of the curing process of holographic gratings with a nematic film-polymer-slice sequence structure

We report on the realization of what we believe to be a new holographic setup for the fabrication of polymer liquid-crystal polymer-slice diffraction gratings, which utilizes an optical-feedback-driven nanopositioning technique. We have increased the stability of the interference pattern by means of a simple piezomirror used in a feedback configuration to keep constant the phase of the interferometer. The feedback system is driven by a proportional, integral, derivative control software, and the stability degree is controlled by the reference signal coming from a standard test grating. A preliminary experimental characterization indicates that good control and stabilization of parasitic fluctuations of the interference pattern are obtained.     

Hashin–Shtrikman Based FE Analysis of the Elastic Behaviour of Finite Random Composite Bodies

This paper demonstrates the effect of non-local interactions in an edge-cracked body made of composite material, in the case that the scale of the body is not large in comparison with the scale of the microstructure, as can occur, for example, in laboratory testing of concrete specimens. Not only are there significant boundary layers in the vicinity of all of the specimen boundaries, but the small size of the body permits their interaction, to alter the value of the mean field globally relative to the value that would be predicted by the use of “ordinary” homogenization, under conditions of “displacement control”. Such an effect would be present even for an uncracked body but the presence of the crack induces strong gradients in the mean field which significantly enhance this effect. The mean strain component tends to become concentrated around the line ahead of the crack in comparison with the prediction of homogenization; there is, in addition, an enhancement of the stress and strain concentrations in the harder phase. The method of analysis is a finite-element implementation of a variational formulation related to the Hashin–Shtrikman variational principle, developed in the context of non-local effective response by the present authors. The present calculations are considered to be more accurate than some previously reported (Luciano and Willis, Journal of the Mechanics and Physics of Solids 53, 1505–1522, 2005) and the conclusions differ correspondingly.     

Studies on FRP-concrete interface with hardening and softening bond-slip law

This latest experimental study proposes a theory that the bond-slip law for a FRP-concrete interface contains linear hardening and exponential softening. On the basis of this law, the paper studies the mechanic behavior and debonding process of a FRP-concrete interface. Firstly, through nonlinear fracture mechanics, the analytical solutions of the interface shear stress, the axial normal stress of FRP and the load–displacement relationship at the loaded end with the single shear test model of FRP-concrete are acquired. The shear stress propagation as well as the debonding process of the whole interface for different bond lengths could be predicted. Secondly, a simplified interface bond-slip law is used by changing the exponential softening law into a linear softening law. In addition, the analytical solutions for the simplified interface bond-slip law could also be obtained. Finally, based on the analytical solutions of the two bond-slip laws, the influences of the FRP bond length and stiffness on load–displacement curve and the ultimate load, as well as stiffness on effective bond length were discussed, with the similarities and differences between the two bond-slip laws also being studied.     

Turing's three philosophical lessons and the philosophy of information

In this article, I outline the three main philosophical lessons that we may learn from Turing's work, and how they lead to a new philosophy of information. After a brief introduction, I discuss his work on the method of levels of abstraction (LoA), and his insistence that questions could be meaningfully asked only by specifying the correct LoA. I then look at his second lesson, about the sort of philosophical questions that seem to be most pressing today. Finally, I focus on the third lesson, concerning the new philosophical anthropology that owes so much to Turing's work. I then show how the lessons are learned by the philosophy of information. In the conclusion, I draw a general synthesis of the points made, in view of the development of the philosophy of information itself as a continuation of Turing's work.     

Antimicrobial packaging based on ɛ‐polylysine bioactive film for the control of mycotoxigenic fungi in vitro and in bread

?‐Poly‐l‐ lysine (?‐PL) is a cationic peptide with a broad‐spectrum antimicrobial activity. This study investigates the use of ?‐PL as natural antimicrobial to inhibit fungal growth and to reduce aflatoxins (AFs) production. Antifungal activity of starch biofilms with different concentrations of ?‐Poly‐l‐ lysine (?‐PL) was determined in solid medium against Aspergillus parasiticus (AFs producer) and Penicillium expansum. Then, biofilms were tested as antimicrobial devices for the preservation of bread loaf inoculated with A. parasiticus CECT 2681 and P. expansum CECT 2278. Shelf life and AFs content were examined. Biofilms with concentrations of ?‐PL less than 1.6 mg/cm² showed no fungal growth inhibition in solid medium, while the antifungal activity of the films with greater than 1.6 mg/cm² of ?‐PL was dose dependent. The shelf life of bread inoculated with A. parasiticus was increased by 1 day with the use of films containing 1.6–6.5 mg ?‐PL/cm², while shelf life of bread tainted with P. expansum was increased by 3 day with 6.5 mg ?‐PL/cm². AFs production was greatly inhibited by ?‐PL biofilms (93–100%). Thus, ?‐PL biofilms could be potentially used as antimicrobial device during bread storage as a natural alternative to the synthetic preservatives.

Practical applications

?‐Polylysin is a natural substance from microbial metabolism. Polylysine has a function to prevent a microbe from proliferating by ionic adsorption in the microbe. ?‐polylysine has a wide antibacterial spectrum and has an obvious lethal effect on Gram‐positive and Gram‐negative bacteria, yeast, mold, viruses, etc. It has a good antibacterial effect on the Gram‐negative bacteria E. coli and Salmonellae, which are difficult to control with other natural preservatives. ?‐Polylysine has already been used generally as a food additive in Japan, Korea and other part of world. In the United States, FDA has recognized the polylysine as a GRAS material. Considered the positive results obtained in the study, this compound could be used for the production of antimicrobial biofilms, applied as separator slices in the loaf bread production, to prevent the growth of the mycotoxigenic fungi A. parasiticus and P. expansum, contributing to reduce the use of the synthetically preservatives in bakery industry and also of the negative impact that these compounds could generate on the health of the end users.