551 research outputs found
Design of low-torque-ripple synchronous reluctance motors
No full textA design approach oriented to minimization of torque-ripple is presented, for synchronous reluctance motors of the transverse-laminated type. First, the possible types of rotors are classified and the more suited rotor structure is evidenced, to be matched to a given stator. Then, the inner rotor design is described, pointing-out the low-ripple measures. Last, experimental results are given, from three different rotors: they confirm the validity of the proposed approach
Corporate Philanthropy in Top Romanian Companies
No full textThis paper aims to provide an insight on the CSR activities developed by top Romanian companies and to analyze whether some economic indexes as number of employees and turnover have a considerable impact on the decision of companies to involve in social responsible activities. The approach is based on a cross-analysis of the statistical weight of donations for eight top company donors in 2007 in Romania. By reviewing the results of the research, the author considers the opportunity to develop a case for CSR, even in its basic form: philanthropy, as a premise for long run social performance.corporate philanthropy, corporate social responsibility, microeconomic indexes, stakeholders.
La caratterizzazione di malte storiche e da restauro provenienti dalla terracotta invetriata policroma "Madonna con il Bambino". Risultati preliminari.
No full textShape change and shape coexistence in134Pr
No full textThe band structure of doubly odd nucleus134Pr has been studied by means of the reaction119Sn(19F,4n) at 87 MeV bombarding energy. Rotational bands built on pgrh11/2otimesvh11/2 and pgrh7/2otimesvh11/2 configurations has been observed. A band consisting of quadrupole transitions, probably involving the vi13/2[600]1/2+ orbital was also weakly populated
Continuum γ rays feeding normal and superdeformed states in Gd nuclei
No full textThe feeding mechanism of the superdeformed bands in 147Gd and 148Gd has been studied via the 124Sn + 29Si reaction at a beam energy of 157 MeV. Using the BGO inner ball of the GASP array, high-energy γ rays have been detected in coincidence with discrete transitions deexciting normal-deformed (ND) and superdeformed (SD) states in the final product nuclei. The slope of the measured high-energy γ-ray spectra depends strongly on the number of emitted neutrons and is somewhat lower for spectra in coincidence with SD bands than for those in coincidence with ND structures. Both observations are qualitatively reproduced by statistical model Monte Carlo calculations, which point out the importance of angular momentum effects in the emission of energetic γ rays. The present data exclude the enhanced population of SD bands when fed through high-energy E1 transitions
Mitigation of Lightning-Induced Overvoltages in Medium Voltage Distribution Lines by Means of Periodical Grounding of Shielding Wires and of Surge Arresters: Modeling and Experimental Validation
No full textIn this paper, we investigate the effect of periodically-grounded shielding wires and surge arresters on the attenuation of lightning-induced voltages. We discuss the adequacy of the commonly made simplification of assuming the shielding wire at ground potential, instead of being treated as one of the conductors of the multiconductor system. We also compare then the mitigation effect of shielding wires with that achievable by the insertion of surge arresters along the line. The computation results are first validated by means of calculations obtained by other authors referring to a simple line configuration, and then by means of experimental results obtained using a reduced-scale line model illuminated by a nuclear electromagnetic pulse (NEMP) simulator. One of the main conclusions is that the effectiveness of shielding wires and surge arresters depends mostly on the spacing between two adjacent grounding points or surge arresters
Switch from short-axis to intermediate-axis rotation in Nd-138
No full textIt is pointed out that the triaxial bands in 138-140Nd and in the Lu/Er nuclei can be understood from the same shell structure effects. Two of the bands in 138Nd, interpreted as signature partners, exhibit a crossing at high spins with a signature splitting which is strongly reduced above the crossing. This behavior is unique among the yrast and close-to-yrast configurations, revealing the mechanism which induces a change of the rotation axis from short to intermediate in the triaxially deformed nucleus. © 2013 American Physical Society
Multiple-highly deformed bands in the nucleus 134Nd
No full textA high statistics experiment has been performed at the GASP detector array employing the 110Pd + 28Si reaction at 130 MeV to populate 134Nd. Our findings do not confirm earlier data on the highly-deformed band of this nucleus. On the other hand, two new rotational sequences have been identified which show the characteristics of the intruder bands in the A = 130 mass region. This is one of the first results indicating the presence of excited highly-deformed bands in nuclei of this region. The behaviour of the dynamical moment of inertia of one of the bands is quite different from that of the highly-deformed bands previously known
Decay out of the highly deformed bands in the odd Nd isotopes: The Nd137 nucleus
No full textThe decay of the highly deformed (HD) band in the nucleus 137Nd has been studied with the GASP array using the reactions 110Pd+30Si and 123Sb+19F. Four decay paths linking the HD band to the normal-deformed states have been established, which fix Iπ=29/2+ for the lowest state of the HD band lying at Ex=4885 keV. The sudden disappearance, at the low spin side, of the HD bands in the 133,135,137Nd isotopes can be explained by total Routhian surface calculations through a change of the nuclear shape which is microscopically related to the transfer of the valence neutron from a N=6 to a N=4 Nilsson orbital
Spectroscopy in the second well of the 148GD nucleus: two quasi-particle and collective excitations
No full textinfo:eu-repo/semantics/publishe
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