Search results for " Distortion"

Test of Special Relativity in a Heavy Ion Storage Ring

2008

Applying system dynamics modeling to foster a cause-and-effect perspective in dealing with behavioral distortions associated with a city's performanc…

2015

This paper aims to show how applying system dynamics methodology to performance management can provide a powerful modeling perspective enabling public sector organizations to prevent, detect, and counteract behavioral distortions associated with performance measurement. A dynamic performance management approach is able to support performance management system designers in outlining and implementing a consistent set of measures that can allow public sector decision-makers to pursue sustainable organizational learning and development. This perspective implies a major shift from a static to a dynamic picture of organizational processes and results. It means framing delays between causes and ef…

Distortions of [Sb2Cl10]4– Bioctahedra and Phase Transitions in the Chloroantimonate(III) (C3H5NH3)2[SbCl5]·(C3H5NH3)Cl

2007

Bis(allylammonium)pentachloroantimonate(III) - allylammonium chloride, (C3H5NH3)2[SbCl5] · (C3H5NH3)Cl, belongs to the chloroantimonate(III) organic-inorganic salts family. The DSC studies of this compound showed two anomalies at 181 K and at 223 K. Both are associated with phase transitions, which mainly occur due to ordering-disordering processes of the organic cations. Between 181 and 223 K the structure is incommensurate. The crystal structure was determined at 298 and 86 K. At both temperatures the crystal structure consists of (C3H5NH3)+ cations, anionic distorted [Sb2Cl10]4− units and isolated Cl− ions. In the room-temperature phase two out of three, and in the low-temperature phase …

Crystal polymorphism of (μ4–O)-body centered adamantanoid Cu(II) complexes

2016

Abstract Two novel polymorphs of [Cu4(μ4–O)(μ–Cl)6(DASO)4], (DASO = diallyl sulfoxide; C6H10OS), rhombic (C) and triclinic (D), were obtained and examined by single crystal X-ray diffraction analysis at two temperatures, 295(2) and 100(1) K. This study, in addition to our recent work on the tetragonal (A) and trigonal (B) forms of the title compound, allowed determining the nature of polymorphism and temperature-induced phase transitions. It is stated that both the packing arrangement and the displacive transformation integrate these structures, forming the symmetrically and thermodynamically related series: A,B → C → D. The C3h → C4 distortion of Cu(II) trigonal bipyramidal coordination ge…

Singularities in L^p-quasidisks

2021

We study planar domains with exemplary boundary singularities of the form of cusps. A natural question is how much elastic energy is needed to flatten these cusps; that is, to remove singularities. We give, in a connection of quasidisks, a sharp integrability condition for the distortion function to answer this question. peerReviewed

Characterization of Current Transformers in the Presence of Harmonic Distortion

2008

The CTs performance under distorted conditions are usually characterized by means of the frequency response test. In this paper a new way to characterize CTs, closer to real operative conditions, is proposed. The harmonic phase angle and ratio errors are measured when the CTs are excited with a nonsinusoidal current composed of a fundamental and one harmonic, with adjustable phase shift. The errors measured using the new approach were found larger than the ones obtained with the frequency response. This suggests that frequency response is not a reliable method to evaluate the CT performance under distorted conditions.

Experimental Analysis of Passive Intermodulation at Waveguide Flange Bolted Connections

2007

[EN] In this paper, the generation of passive intermodulation at rectangular waveguide flange bolted connections is investigated. An exhaustive series of tests has been performed in order to provide understanding on the physics lying behind such a phenomenon. In particular, the intermodulation response of the system has been studied as a function of the applied torque to the flange screws. It has been found that, in some situations, the intermodulation response differs from its expected behavior. An interpretation of such discrepancies is given, and practical guidelines for the design of waveguide flanges free of passive intermodulation are provided as well.

Characterization and Error Compensation of a Rogowski Coil in the Presence of Harmonics

2011

This paper reports the results of an experimental study dealing with a commercial Rogowski coil current transducer (RCCT) in the presence of harmonic distortion. The RCCT was observed under two conditions: 1) sinusoidal excitation with frequencies from 50 to 750 Hz and 2) nonsinusoidal excitation using fundamental frequency and one harmonic, with adjustable amplitude and phase shift. The experimental results show only a weak dependence of the harmonic current ratio error and phase displacement on the amplitude and phase shift of the excitation harmonic. The phase displacement is also independent of the conductor position within the Rogowski coil window. An error compensation method, based o…

Performances of a three-phase five-level cascaded H-bridge inverter with phase shifted B-spline based modulation techniques

2017

This paper presents a novel study of the performances of a five-level three-phase Cascaded H-Bridge Multilevel Inverter with Phase Shifted B-Spline based modulation techniques. The study has been focused on the use of B-Spline functions as carrier signals in order to evaluate the performances of the converter in terms of harmonic content on the output voltage. In the first step of this analysis the THD% has been taken into account to compare the voltage waveforms. Interesting results have been found on the fundamental amplitude of the phase and line voltage. Moreover, harmonic spectra has been compared to evaluate the different harmonic distribution in the voltage waveforms. In this work th…

Harmonic reduction in CHB 13-level inverters by PAM fundamental-frequency strategy

2019

In this paper cascaded H-bridges (CHB) 13-level inverters are considered and a particular pulse amplitude modulation (PAM) strategy is introduced to mitigate or eliminate many harmonic components on the output voltage, in order to obtain low Total Harmonic Distortion (THD) factor. This procedure defines different dc voltage sources and sets of six switching angles, depending on an integer parameter $q$ belonging to the close interval $I=[11, 15]$ . The obtained THD doesn't depend on modulation index $m$ . The control of $m$ is made by changing the dc voltage sources that depend linearly on m, while the switching angles remain constant. An investigation about the role of the $q$ parameter on…