1,979 research outputs found

    Service delivery process improvement using decision support systems in two manufacturing companies

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    Abstract The Product-Service Systems (PSS) offering is spreading on the market. Companies are becoming aware that selling bundles of products and services can create additional value for them and for the customers. Despite this, the provision of additional services not natively designed to improve products usage is not trivial. In fact, not only services must be correctly customized on the customers' necessities but also the way they are provided must be redesigned. An effective service delivery process is fundamental if companies want to create additional value from their service portfolio. The way they manage the phases leading to the service provision influences the way and the time required to deliver them. This work compares the service delivery process of two manufacturing companies headquartered in different parts of the world and selling products for the B2B market. The analyses performed on the service delivery processes highlighted how, despite the technological complexity the products, the management of the service delivery process is not automated, but it is still managed by humans without any Decision Support System (DSS) by the companies' service departments. For this reason, authors proposed improvements for the two service delivery processes through the introduction of DSS able to handle part of the process and, in turn, smooth them, shortening the time required to deliver services to customers and, so, increasing their satisfaction

    On the natural stabilization of convection dominated problems using high order Bubnov–Galerkin finite elements

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    In the case of dominating convection, standard Bubnov–Galerkin finite elements are known to deliver oscillating discrete solutions for the convection–diffusion equation. This paper demonstrates that increasing the polynomial degree (p-extension) limits these artificial numerical oscillations. This is contrary to a widespread notion that an increase of the polynomial degree destabilizes the discrete solution. This treatise also provides explicit expressions as to which polynomial degree is sufficiently high to obtain stable solutions for a given Péclet number at the nodes of a mesh

    Culture of skeletal myoblasts from human donors aged over 40 years: dynamics of cell growth and expression of differentiation markers

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    BACKGROUND: Local myogenesis, neoangiogenesis and homing of progenitor cells from the bone marrow appear to contribute to repair of the infarcted myocardium. Implantation into heart tissues of autologous skeletal myoblasts has been associated with improved contractile function in animal models and in humans with acute myocardial ischemia. Since heart infarction is most prevalent in individuals of over 40 years of age, we tested whether culture methods available in our laboratory were adequate to obtain sufficient numbers of differentiated skeletal myoblasts from muscle biopsy specimens obtained from patients aged 41 to 91. METHODS AND RESULTS: No matter of donor age, differentiated skeletal muscle cells could be produced in vitro in amounts adequate for cellular therapy (≥300 millions). Using desmin as a cytoplasmic marker, about 50% cultured cells were differentiated along myogenic lineages and expressed proteins proper of skeletal muscle (myosin type I and II, actin, actinin, spectrin and dystrophin). Cytogenetic alterations were not detected in cultured muscle cells that had undergone at least 10 population doublings. Molecular methods employed for the screening of persistent viral infections evidenced that HCV failed to replicate in muscle cells cultured from one patient with chronic HCV infection. CONCLUSION: The proposed culture methods appear to hold promise for aged patients not only in the field of cardiovascular medicine, but also in the urologic and orthopedic fields

    Quasiparticle energies for large molecules: a tight-binding GW approach

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    We present a tight-binding based GW approach for the calculation of quasiparticle energy levels in confined systems such as molecules. Key quantities in the GW formalism like the microscopic dielectric function or the screened Coulomb interaction are expressed in a minimal basis of spherically averaged atomic orbitals. All necessary integrals are either precalculated or approximated without resorting to empirical data. The method is validated against first principles results for benzene and anthracene, where good agreement is found for levels close to the frontier orbitals. Further, the size dependence of the quasiparticle gap is studied for conformers of the polyacenes (C4n+2H2n+4C_{4n+2}H_{2n+4}) up to n = 30.Comment: 10 pages, 5 eps figures submitted to Phys. Rev.

    Spin-orbit coupling in a half-filled t2gt_{2g} shell: the case of 5d35d^3 K2_2ReCl6_6

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    The half-filled t2gt_{2g} shell of the t2g3t_{2g}^3 configuration usually, in LS coupling, hosts a S = 3/2 ground state with quenched orbital moment. This state is not Jahn-Teller active. Sufficiently large spin-orbit coupling ζ\zeta has been predicted to change this picture by mixing in orbital moment, giving rise to a sizable Jahn-Teller distortion. In 5d35d^3 K2_2ReCl6_6 we study the electronic excitations using resonant inelastic x-ray scattering (RIXS) and optical spectroscopy. We observe on-site intra-t2gt_{2g} excitations below 2 eV and corresponding overtones with two intra-t2gt_{2g} excitations on adjacent sites, the Mott gap at 2.7 eV, t2gt_{2g}-to-ege_g excitations above 3 eV, and charge-transfer excitations at still higher energy. The intra-t2gt_{2g} excitation energies are a sensitive measure of ζ\zeta and Hund's coupling JHJ_H. The sizable value of ζ\zeta \approx 0.29 eV places K2_2ReCl6_6 into the intermediate coupling regime, but ζ/JH0.6\zeta/J_H \approx 0.6 is not sufficiently large to drive a pronounced Jahn-Teller effect. We discuss the ground state wavefunction in a Kanamori picture and find that the S = 3/2 multiplet still carries about 97 % of the weight. However, the finite admixture of orbital moment allows for subtle effects. We discuss small temperature-induced changes of the optical data and find evidence for a lowering of the ground state by about 3 meV below the structural phase transitions.Comment: 16 pages, 14 figure

    Electronic excitations in 5d45d^4 J=0 Os4+^{4+} halides studied by RIXS and optical spectroscopy

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    We demonstrate that the cubic antifluorite-type halides K2_2OsCl6_6, K2_2OsBr6_6, and Rb2_2OsBr6_6 are excellent realizations of non-magnetic J=0 compounds. The magnetic susceptibility shows the corresponding Van-Vleck type behavior and no sign of defects. We investigate the electronic excitations with two complementary techniques, resonant inelastic x-ray scattering (RIXS) and optical spectroscopy. This powerful combination allows us to thoroughly study, e.g., on-site intra-t2gt_{2g} excitations and t2gt_{2g}-to-ege_g excitations as well as inter-site excitations across the Mott gap and an exciton below the gap. In this way, we determine the electronic parameters with high accuracy, altogether yielding a comprehensive picture. In K2_2OsCl6_6, we find the spin-orbit coupling constant ζ\zeta=0.34 eV, Hund's coupling JHJ_H=0.43 eV, the onset of excitations across the Mott gap at Δ\Delta=2.2 eV, the cubic crystal-field splitting 10Dq=3.3 eV, and the charge-transfer energy ΔCT\Delta_{CT}=4.6 eV. With JH/ζJ_H/\zeta=1.3, K2_2OsCl6_6 is in the intermediate-coupling regime. In a t2gt_{2g}-only Kanamori picture, the above values correspond to ζeff\zeta^{eff}=0.41 eV and JHeffJ_H^{eff}=0.28 eV, which is very close to results reported for related 5d45d^4 iridates. In the tetragonal phase at 5 K, the non-cubic crystal field causes a peak splitting of the J=1 state as small as 4 meV. Compared to K2_2OsCl6_6, the bromides K2_2OsBr6_6 and Rb2_2OsBr6_6 show about 12-14 % smaller values of 10Dq and ΔCT\Delta_{CT}, while the spin-orbit-entangled intra-t2gt_{2g} excitations below 2 eV and hence ζ\zeta and JHJ_H are reduced by less than 4 %. Furthermore, the Mott gap in K2_2OsBr6_6 is reduced to about 1.8 eV.Comment: 14 pages, 14 figure

    How can ski resorts get smart? Transdisciplinary approaches to sustainable winter tourism in the European Alps

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    Climate change and the call for reduction of greenhouse gas emissions, the efficient use of (renewable) energy, and more resilient winter tourism regions, forces ski resorts across the European Alps to look for \u201csmart\u201d approaches to transition towards a sustainable, low-carbon economy. Drawing on the smart-city concept and considering the different historical developments of Alpine resorts, the Smart Altitude Decision-Making Toolkit was developed using a combination of an energy audit tool, a WebGIS, and collaborative and innovative living labs installed in Les Orres (France), Madonna di Campiglio (Italy), Krvavec (Slovenia), and Verbier (Switzerland). This step-by-step Decision-Making Toolkit enables ski resorts to get feedback on their energy demand, an overview of the locally available sources of renewable energy, and insights regarding their potential for improving their energy efficiency by low-carbon interventions. The Decision-Making Toolkit is suitable for knowledge transfer between stakeholders within living labs and moreover provides the flexibility for tailor-made low-carbon strategies adapting to the unique assets and situatedness of ski resorts

    NUTRITIONAL ACCUMULATION FOR SALAD AND ITALIAN TOMATOES GROWN IN A PROTECTED ENVIRONMENT

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    ABSTRACT Tomato cultivation in a protected environment is an important tool for increasing yield, quality, and regularity of production. However, nutrient imbalance in this production system can lead to short-and long-term losses. This study aimed to characterize plant growth and nutrient accumulation and export of two tomato hybrids of the Salad (‘Stella TY’) and Italian (‘HS 1188’) groups in a protected environment and determine the accumulated thermal sum. The treatments consisted of evaluation times. Dry mass and nutrient accumulation could be determined by a sigmoidal non-linear model for both hybrids grown in the protected environment. The cumulative nutrient order was K > Ca > N > S > Mg > P > Mn > Zn > Fe > Cu > B for ‘Stella TY’ and K > N > Ca > S > P > Mg > Mn > Fe > Zn > Cu > B for ‘HS1188’, with yields of 105.7 and 103.4 t ha−1, respectively. The accumulated thermal sum was 1851.7 degree days at 126 days after transplanting (DAT)
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