On the particle spectrum and the conformal window

We study the SU(3) gauge theory with twelve flavours of fermions in the fundamental representation as a prototype of non-Abelian gauge theories inside the conformal window. Guided by the pattern of underlying symmetries, chiral and conformal, we analyze the two-point functions theoretically and on the lattice, and determine the finite size scaling and the infinite volume fermion mass dependence of the would-be hadron masses. We show that the spectrum in the Coulomb phase of the system can be described in the context of a universal scaling analysis and we provide the nonperturbative determination of the fermion mass anomalous dimension gamma*=0.235(46) at the infrared fixed point. We comment on the agreement with the four-loop perturbative prediction for this quantity and we provide a unified description of all existing lattice results for the spectrum of this system, them being in the Coulomb phase or the asymptotically free phase. Our results corroborate the view that the fixed point we are studying is not associated to a physical singularity along the bare coupling line and estimates of physical observables can be attempted on either side of the fixed point. Finally, we observe the restoration of the U(1) axial symmetry in the two-point functions.Comment: 40 pages, 22 figure

One,Two,Zero: Scales of Strong Interactions

We discuss our results on QCD with a number of fundamental fermions ranging from zero to sixteen. These theories exhibit a wide array of fascinating phenomena which have been under close scrutiny, especially in recent years, first and foremost is the approach to conformality. To keep this review focused, we have chosen scale generation, or lack thereof as a guiding theme, however the discussion will be set in the general framework of the analysis of the phases and phase transitions of strong interactions at zero and nonzero temperature.Comment: 15 pages, prepared for IJMPA Special Issue 'Recent Nonperturbative Developments in QCD-like Theories

Chiral symmetry restoration in QCD with many flavours

We discuss the phases of QCD in the parameter space spanned by the number of light flavours and the temperature with respect to the realisation of chiral and conformal symmetries. The intriguing interplay of these symmetries is best studied by means of lattice simulations, and some selected results from our recent work are presented here.Comment: 10 pages, proceedings of the 9th International Workshop on Critical Point and Onset of Deconfinement, 17-21 November, 2014, ZiF, Bielefeld, German

Quark matter revisited with non extensive MIT bag model

In this work we revisit the MIT bag model to describe quark matter within both the usual Fermi-Dirac and the Tsallis statistics. We verify the effects of the non-additivity of the latter by analysing two different pictures: the first order phase transition of the QCD phase diagram and stellar matter properties. While, the QCD phase diagram is visually affected by the Tsallis statistics, the resulting effects on quark star macroscopic properties are barely noticed.Comment: 10 pagens, 5 figure

Tilted boxes on inclined planes

We propose the study of a box placed on an inclined plane, with an initial tilt with respect to the plane. This is a paradigmatic example of the role played by friction as a link between translational and rotational motion. This example has two advantages over the usual example of a sphere (or cylinder) rolling down an inclined plane. First, it provides a good model for a much greater variety of "real-life" situations. Second, it exhibits a much richer structure in parameter space, even when the box starts from rest. (C) 2000 American Association of Physics Teachers

Production of thermoplastic matrix towpregs for higly demanding and cost - effective commercial applications

This work reviews the work made in last years to produce thermoplastic matrix towpregs to highly demanding and more cost-effective commercial applications using a powder coating technology developed in Portugal by Minho and Porto Universities. Different thermoplastic matrices and continuous fibre reinforcements were used in the towpregs produced for highly demanding markets (e.g., carbon fibre reinforced Primospire towpreg) and for more commercial applications (e.g., glass fibre reinforced polypropylene and polyvinyl chloride towpregs). The relevant processing parameters, such as, fibre pull-speed and furnace temperature were varied to determine their influence on the polymer mass fraction obtained in the studied raw materials. Several technologies were also developed and used (compression moulding, pultrusion and filament winding) to process composite parts with adequate properties for the envisaged markets at compatible production rates. The obtained results lead us to conclude that the studied thermoplastic matrix towpregs and their processed composite parts have very interesting conditions for being applied both in highly advanced and cost-effective markets.European Space Agency (ESA) e Fundação para a Ciência e a Tecnologia (FCT

Processing thermoplastic matrix towpregs by pultrusion

In this work glass fibre reinforced polypropylene (GF/PP) towpregs, continuously produced at different processing conditions in a dry powder coating equipment, were processed into final composites by using a developed prototype pultrusion equipment. The influence of the fibre pull-speed and furnace temperature used in the dry coating towpregger on the polymer content of final produced towpregs was determined. Optical microscopy and SEM were techniques also used to assess quality of the produced GF/PP towpregs. The GF/PP towpregs were then processed into a composite bar by using a prototype pultrusion machine that will be described and presented in the workshop. Studies were carried out to determine the influence of the pull-speed and temperatures used in the pultrusion heated and cooled dies on the mechanical and other relevant physical properties of final composite profiles. Finally, the final composite profiles processing window and optimisation will be discussed and presented

Production of thermoplastic matrix towpregs for highly demanding and cost-effective commercial applications

This work reviews the work made in last years to produce thermoplastic matrix towpregs to highly demanding and more cost-effective commercial applications using a powder coating technology developed in Portugal by Minho and Porto Universities. Different thermoplastic matrices and continuous fibre reinforcements were used in the towpregs produced for highly demanding markets (e.g., carbon fibre reinforced Primospire towpreg) and for more commercial applications (e.g., glass fibre reinforced polypropylene and polyvinyl chloride towpregs). The relevant processing parameters, such as, fibre pull-speed and furnace temperature were varied to determine their influence on the polymer mass fraction obtained in the studied raw materials. Several technologies were also developed and used (compression moulding, pultrusion and filament winding) to process composite parts with adequate properties for the envisaged markets at compatible production rates. The obtained results lead us to conclude that the studied thermoplastic matrix towpregs and their processed composite parts have very interesting conditions for being applied both in highly advanced and cost-effective markets.The authors acknowledge the European Space Agency (ESA) and the Portuguese Foundation for Science and Technology (FCT) for the financial support given to the work carried on

Knowledge management in a dynamic manufacturing context: a case study

Continuous improvement or just improvement is a necessity for companies in a dynamic environment. To be more competitive companies must adapt to the changing internal and external environment. To adapt implies making decisions and taking actions in an informed way. Assuming that Knowledge is widespread over the company, companies may develop knowledge management systems (KMS) to capture and disseminate knowledge, but there is not a universal set of requirements to do it. This paper shows, through a case study, a methodology to manage knowledge developed by a renowned manufacturer of electronic products. In this company, it is studied the impact of process improvement on management practices and collaborators behavior. The development of a KMS, in a dynamic context, is discussed and assessed through a survey. The features of this system allow us to consider it as a KMS. The KMS leverages the use of collaborative tools and supports the verified performance improvements.This work has been supported by COMPETE: POCI-01-0145-FEDER-007043 and FCT – Fundação para a Ciência e Tecnologia within the Project Scope: UID/CEC/00319/2013

Processing of continuous fibre reinforced thermoplastics

ECCM15 - 15TH EUROPEAN CONFERENCE ON COMPOSITE MATERIALS, Venice, Italy, 24-28 June 2012Towpregs based on different fibres and thermoplastic matrices were processed for highly demanding and more commercial applications by different composite processing technologies. In the technologies used, compression moulding and pultrusion, the final composite pr ocessing parameters were studied in order to obtain composites with adequate properties at industrial compatible production rates. The produced towpregs were tested to verify its polymer content and degree of impregnation. The obtained results have shown t hat the coating line enabled to produce, with efficiency and industrial scale speed rates, thermoplastic matrix towpregs that may be used to manufacture composites for advanced and larger volume commercial markets