2,346 research outputs found

    Coupling production networks and regional assets in manufacturing clusters

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    Paradoxically, the ongoing process of globalisation goes hand in hand with a surge of interest in the ‘local’ sources of firm competitiveness. In this paper, we develop a frame of analysis that helps to understand ‘coupling’ of production networks and regional development. Our aim is to reflect on the ‘spatiality’ of different types of networks, and to study the dynamic coupling process between these networks and regional assets. We apply the framework to two case studies – shipbuilding in Turku and machine building in Porto. Our analysis points towards the relevance of regional assets facilitating this coupling process and in strengthening regions as magnets for global production networks, reinforcing the long term sustainability of different types of clusters

    Monte Carlo study of the critical temperature for the planar rotator model with nonmagnetic impurities

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    We performed Monte Carlo simulations to calculate the Berezinskii-Kosterlitz-Thouless (BKT) temperature TBKTT_{BKT} for the two-dimensional planar rotator model in the presence of nonmagnetic impurity concentration (ρ)(\rho). As expected, our calculation shows that the BKT temperature decreases as the spin vacancies increase. There is a critical dilution ρc0.3\rho_c \approx 0.3 at which TBKT=0T_{BKT} =0. The effective interaction between a vortex-antivortex pair and a static nonmagnetic impurity is studied analytically. A simple phenomenological argument based on the pair-impurity interaction is proposed to justify the simulations.Comment: 5 pages, 5 figures, Revetex fil

    VirtualECare: group support in collaborative networks organizations for digital homecare

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    Collaborative Work plays an important role in today’s organizations and normally in areas where decisions must be made. However, any decision that involves a collective or group of decision makers is, by itself, complex but is becoming normal in recent years. In this work we present the VirtualECare project (Figure 10), intelligent multi‐agent system able to monitor, interact and serve its customers, which are, normally, in need of care services. In the last years there has been a substantially increase in the number of people needed of intensive care, especially among the elderly, a phenomenon that is related to population ageing. However, this is not exclusive of the elderly, as diseases as obesity, diabetes, and blood pressure have been increasing among young adults. As a new reality, it has to be dealt by the health sector, and particularly by the public one. Thus, the importance of finding new and cost effective ways for health care delivery are of particular importance, especially when one want them not to be removed from their “habitat”. Following this line of thinking, the VirtualECare project will be presented, like similar ones that preceded it. Recently we have assisted to a growing interest in combining the advances in information society ‐ computing, telecommunications and presentation – in order to create Group Decision Support Systems (GDSS). Indeed, the new economy, along with increased competition in today’s complex business environments, takes the companies to seek complementarities in order to increase competitiveness and reduce risks. Under these scenarios, planning takes a major role in a company life. However, effective planning depends on the generation and analysis of ideas (innovative or not) and, as a result, the idea generation and management processes are crucial. Our objective is to apply the above presented GDSS to a new area. We believe that the use of GDSS in the healthcare arena will allow professionals to achieve better results in the analysis of one’s Electronically Clinical Profile (ECP). This achievement is vital, regarding the explosion of knowledge and skills, together with the need to use limited resources and get better results

    Analysis of pancreas histological images for glucose intolerance identificationusing ImageJ-preliminary results

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    The observation in microscopy of histological sections allows us to evaluate structural differences, in pancreatic cells, between rats with normal glucose tolerance and with glucose intolerance (pre-diabetic) situation. Nevertheless, this pre-diabetic condition implies subtle changes in islets of Langerhans structure. This and the normal variability among sampled cells makes difficult the task of identifying glucose intolerance (pre-diabetic situation) with a low level of error. This paper presents preliminary results in the processing of histological pancreas images with the goal of identifying pre-diabetic situation in Wistar rats. The immediate goal of this work is to evaluate the performance of a classifier based in a morphometric measurement of the histological images and to assess the potential for image based automatic processing and classification. A set of 90 images, were used (58 from rats with normal glucose tolerance, and 32 from pre-diabetic ones). These images were segmented manually using ImageJ. This segmentation and area measurements have been speedup by the application of ImageJ macros which were defined for this purpose. The ratio, between the area of -cells and the islets of Langerhans , was used has the indicator of the prediabetic situation. Considering this feature, a receiver operating characteristic analysis has been performed. True positive rate, vs. false positive rate shows the predicted performance of a binary classifier as its discrimination threshold is varied

    On the characterisation of a Bragg spectrometer with X-rays from an ECR source

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    Narrow X-ray lines from helium-like argon emitted from a dedicated ECR source have been used to determine the response function of a Bragg crystal spectrometer equipped with large area spherically bent silicon (111) or quartz (101ˉ\bar{1}) crystals. The measured spectra are compared with simulated ones created by a ray-tracing code based on the expected theoretical crystal's rocking curve and the geometry of the experimental set-up.Comment: Version acceptee (NIM

    Identificação de polimorfismos de nucleotideos unicos em montagem de Ests de três espécies de café

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    The sequencing of the ESTS of three coffee species transcriptome, Coffea arabica, Coffea canephora and Coffea racemosa, opened many possibilities for studying different characteristics between these species. Fenotipical characteristics of agronomic interest can be molecularly studied through the transcript analysis of these three species and also through the mapping of a set of target genes for genetic improvement programs. In this work, a clustering for similarity of ESTs of the three species was carried, aiming a study of single nucleotide polymorphisms (SNPs). Using parameters of similarity (>95%) and overlapping (>100 bp) 15,885 contigs have been constructed, which contain a frequency of 0,47 SNPs for 100 bp. The results were stored for consults and future studies of variability in individuals of each species and between these three species. (Résumé d'auteur

    Discriminating among Earth composition models using geo-antineutrinos

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    It has been estimated that the entire Earth generates heat corresponding to about 40 TW (equivalent to 10,000 nuclear power plants) which is considered to originate mainly from the radioactive decay of elements like U, Th and K, deposited in the crust and mantle of the Earth. Radioactivity of these elements produce not only heat but also antineutrinos (called geo-antineutrinos) which can be observed by terrestrial detectors. We investigate the possibility of discriminating among Earth composition models predicting different total radiogenic heat generation, by observing such geo-antineutrinos at Kamioka and Gran Sasso, assuming KamLAND and Borexino (type) detectors, respectively, at these places. By simulating the future geo-antineutrino data as well as reactor antineutrino background contributions, we try to establish to which extent we can discriminate among Earth composition models for given exposures (in units of kt\cdot yr) at these two sites on our planet. We use also information on neutrino mixing parameters coming from solar neutrino data as well as KamLAND reactor antineutrino data, in order to estimate the number of geo-antineutrino induced events.Comment: 24 pages, 10 figures, final version to appear in JHE

    De Sitter and Schwarzschild-De Sitter According to Schwarzschild and De Sitter

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    When de Sitter first introduced his celebrated spacetime, he claimed, following Schwarzschild, that its spatial sections have the topology of the real projective space RP^3 (that is, the topology of the group manifold SO(3)) rather than, as is almost universally assumed today, that of the sphere S^3. (In modern language, Schwarzschild was disturbed by the non-local correlations enforced by S^3 geometry.) Thus, what we today call "de Sitter space" would not have been accepted as such by de Sitter. There is no real basis within classical cosmology for preferring S^3 to RP^3, but the general feeling appears to be that the distinction is in any case of little importance. We wish to argue that, in the light of current concerns about the nature of de Sitter space, this is a mistake. In particular, we argue that the difference between "dS(S^3)" and "dS(RP^3)" may be very important in attacking the problem of understanding horizon entropies. In the approach to de Sitter entropy via Schwarzschild-de Sitter spacetime, we find that the apparently trivial difference between RP^3 and S^3 actually leads to very different perspectives on this major question of quantum cosmology.Comment: 26 pages, 8 figures, typos fixed, references added, equation numbers finally fixed, JHEP versio

    Asymmetries between the production of D+ and D- mesons from 500 GeV/c pi- nucleon interactions as a function of xF and pt**2

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    We present asymmetries between the production of D+ and D- mesons in Fermilab experiment E791 as a function of xF and pt**2. The data used here consist of 74,000 fully-reconstructed charmed mesons produced by a 500 GeV/c pi- beam on C and Pt foils. The measurements are compared to results of models which predict differences between the production of heavy-quark mesons that have a light quark in common with the beam (leading particles) and those that do not (non-leading particles). While the default models do not agree with our data, we can reach agreement with one of them, PYTHIA, by making a limited number of changes to parameters used

    Mass Splitting and Production of Σc0\Sigma_c^0 and Σc++\Sigma_c^{++} Measured in 500GeV500 {GeV} π\pi^- -N Interactions

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    From a sample of 2722±782722 \pm 78 Λc+\Lambda_c^+ decaying to the pKπ+pK^-\pi^+ final state, we have observed, in the hadroproduction experiment E791 at Fermilab, 143±20143 \pm 20 Σc0\Sigma_c^0 and 122±18122 \pm 18 Σc++\Sigma_c^{++} through their decays to Λc+π±\Lambda_c^+ \pi^{\pm}. The mass difference M(Σc0)M(Λc+M(\Sigma_c^0) - M(\Lambda_c^+) is measured to be (167.38±0.29±0.15)MeV(167.38\pm 0.29\pm 0.15) {MeV}; for M(Σc++)M(Λc+)M(\Sigma_c^{++}) - M(\Lambda_c^+), we find (167.76±0.29±0.15)MeV(167.76\pm 0.29\pm0.15) {MeV}. The rate of Λc+\Lambda_c^+ production from decays of the Σc\Sigma_c triplet is (22\pm 2\pm 3) {%} of the total Λc+\Lambda_c^+ production assuming equal rate of production from all three, as measured for Σc0\Sigma_c^0 and Σc++\Sigma_c^{++}. We do not observe a statistically significant Σc\Sigma_c baryon-antibaryon production asymmetry. The xFx_F and pt2p_t^2 spectra of Λc+\Lambda_c^+ from Σc\Sigma_c decays are observed to be similar to those for all Λc+\Lambda_c^+'s produced.Comment: 15 pages, uuencoded postscript 3 figures uuencoded, tar-compressed fil
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