677 research outputs found
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.
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. © 1998 IEEE
A simple current regulator for flux-weakened operation of high performance synchronous reluctance drives
No full textHigh anisotropy synchronous reluctance machines are becoming a practical and cheap choice for high performance drives, but simple control solutions are still investigated because of control sensitivity to anisotropy ratio. Torque sensitivity is discussed with respect to model errors due to iron loss and saturation. A control strategy is derived, based on simple three-phase current regulation with feed-forward emf compensation. The lack of control at voltage saturation, usually related to this choice, is reinvestigated by means of stability analysis, defining the inverter's model up to six-step operation. A novel voltage phase-leading method is then proposed and analysed. Analytical design relationships are derived and implemented in a prototype drive adopting a high anisotropy motor. Experimental results verify analytically predicted flux-weakened performances, up to quasi-six-step operation. Interesting drive behaviour is also shown in the constant-torque speed range
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
Step-wise occupation of the νi13/2 intruder orbital in the doubly-odd nucleus 132Pr
No full textFive rotational bands involving intruder and/or extruder orbitals have been observed in the doubly-odd nucleus 132Pr. One of them is observed for the first time. The properties of the new band are similar to those of the excited highly deformed band of 134Nd, which has a configuration involving one i13/2 neutron at low frequency that is crossed at high frequency by a configuration with two i13/2 neutrons. This behavior indicates that the stepwise occupation of νi13/2 intruder orbitals is an efficient mechanism for building high angular momentum in the light A∼130 nuclei
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