Search results for "Measure"
showing 10 items of 4687 documents
On the Porosity of Free Boundaries in Degenerate Variational Inequalities
2000
Abstract In this note we consider a certain degenerate variational problem with constraint identically zero. The exact growth of the solution near the free boundary is established. A consequence of this is that the free boundary is porous and therefore its Hausdorff dimension is less than N and hence it is of Lebesgue measure zero.
The paradox of endogenous poverty line in the poverty indices
2007
february 23-25, 2007; When measuring poverty, the poverty line is considered to be relatively determined as a percentage of the median income or as a percentage of the average income so as to allow international comparisons. The poverty line relative to the median income may be described as endogenous in contrast with the poverty line relative to the average income which may be described as exogenous because it is independent of the normalized distribution of incomes. As the existing literature is focused on the properties of the indices but not on the respective interest of the endogenous and exogenous poverty lines, this paper compares the two definitions of the relative poverty. The Rela…
An Innovative Coupling Solution for Power Line Communication in MV Electrical Networks
2019
One of the main problems in the diffusion of power line communication (PLC) in medium voltage (MV) networks is the need of a dedicated PLC coupler to be installed all over the network. To avoid this problem, the authors have studied, prototyped and patented an innovative PLC coupling solution which uses electrical elements embedded in most of the switchgears already installed in MV networks, i.e. the capacitive dividers of the voltage detecting systems (VDS). The new solution prototype is described in this paper, highlighting the advantages in terms of a significant reduction of both direct costs of equipment and infrastructures and indirect costs of installation and service interruption. T…
Innovative Solutions for the Integration of Renewable Energies on Tunisian and Sicilian Electrical Grids
2022
The rapid spread of distributed generation from renewable energy sources, combined with their unpredictable behavior, requires the continuous monitoring and control by the Distribution System Operator, in order to guarantee the stability and efficiency of the distribution network. Thus, in this paper a new measurement and communication architecture is proposed, which foresees the use of innovative devices and different technology-oriented solutions, even redundant ones, which allows the transition from passive to active electricity distribution network, with minimal structural changes. The architecture has been developed in the framework of the SInERT project (Italy-Tunisia cross-border coo…
An Innovative Power Line Communication solution For Medium Voltage Smart Grids Applications
2018
This paper summarizes the authors research activity concerning the design, modeling and experimental characterization of a new coupling system for medium voltage (MV) narrow band power line communications (NB-PLC). The proposed solution has been patented by authors and it exploits the capacitive divider of voltage detecting systems (VDSs) normally used to reveal the mains voltage presence, thus avoiding the use of dedicated MV couplers. In the following, the modeling of the VDS capacitive divider is presented and the interface card design is described, based on simulation of the whole PLC transmission channel. Laboratory tests are also presented. Finally, the results are shown of an on-fiel…
Harmonic sources detection in power systems via nonactive power measurements according to IEEE Std. 1459-2010: theoretical approach and experimental …
2010
In this paper an enhanced decision-making strategy is presented for the detection of harmonic sources in power systems able to detect also which is the prevailing nature of the disturbance (nonlinearity or unbalance). It makes use of some simple indices, which are evaluated by means of the measurements of some nonactive power quantities, proposed by the authors and derived from the approach of the IEEE Std. 1459-2010. The decision-making rules for the proposed strategy are presented and discussed by means of simulation and experimental tests. The results obtained are presented, showing the effectiveness of the proposed strategy for the detection of the dominant harmonic source upstream or d…
A Line Impedance Calculator Based on a G3 PLC Modem Platform
2022
Power line communication (PLC) is one of the most today used technologies for both automatic meter reading and many other smart grid applications. In this framework, a characterization of the electrical network in the PLC frequency range is needed in terms of impedance measurement and received signal level. This can allow choosing the most suitable and less noisy frequency ranges for PLC transmission. Usually, these characterization measurements are performed with dedicated instrumentation and in the absence of mains voltage. This article wants to propose an alternative solution, which allows these kinds of measurements to be performed using electronic boards currently used as on-field appl…
Uncertainty evaluation in load flow analysis: real MV distribution networks case studies
2018
This work investigates the measurement uncertainty impact on load flow analysis in medium voltage (MV) distribution networks. The considered algorithm is a simplified load flow algorithm (LFA), developed by authors, which is based on the load power measurements at each secondary substation and one voltage measurement at the slack bus (i.e. the voltage at the MV bus bars of the primary substation). In the viewpoint of a real implementation, to reduce monitoring system costs, the LFA makes use of low voltage (LV) load power measurements for all the substations except those of MV users, where MV transducers are usually already installed. The uncertainties on LFA input quantities (load powers a…
THE ADMINISTRATIVE JUSTICE IN SPAIN: CURRENT SITUATION AND CHALLENGES
2016
Since the Spanish Constitution of 1978 there has been a full and effective administrative justice. The citizens have the possibility to request a judicial review of decisions taken by the public Administrations, while being either the owners of a subjective right or of a legitimate interest. The interim judicial protection is not limited to the suppression of the act or general provision and the Courts are invested with direct powers to enforce their sentences. However, different problematic issues about the inactivity of the public Administrations and the enforcement of sentences are the new challenges to ensure the administrative justice. To this it must be added that there are problems r…
L'"ETERNO RITORNO": VACILLA L'AUTONOMA VALUTAZIONE IN SEDE CAUTELARE
2019
By law no. 47/2015, the legislator has stated that the assessment on conditions of applicability of precautionary measures has to be autonomous, also excluding a power of integration by the judicial review Tribunal. However, some judgments regarding cumulative judicial orders reveal a “return to the past”. This latter requires a clear position by the Supreme Court aimed at reaffirming constitutional values underlying the autonomous assessment