Search results for "SIMULATION"
showing 10 items of 5095 documents
Polluting loads detection in power systems: a decision-making strategy based on nonactive power measurements
2010
In this paper a novel decision-making strategy is proposed for the detection of polluting loads in three-phase power systems. It makes use of simple indices, which are expressed as a function of some nonactive power quantities, previously proposed by the authors and derived from the approach of the IEEE Std. 1459–2000. The decision-making rules for the proposed strategy are presented and discussed, by means of some simulation tests.
A novel approach based on nonactive powers for the identification of disturbing loads in power systems
2007
In this paper, a new approach is proposed for the detection of harmonic sources in polluted power systems. It is a single- point strategy, based on a comparison among different "nonactive" power quantities proposed in literature that, in the same working conditions, assume different values at the same metering section. Some simulations tests were carried out on a standard IEEE test system proposed by other authors as a benchmark system for the analysis of multipoint measurement techniques for harmonic pollution monitoring. The obtained results show that the proposed single-point approach is in agreement with other strategies already proposed in the literature and can provide useful indicati…
Comparison of Nonactive Powers for the Detection of Dominant Harmonic Sources in Power Systems
2008
This paper deals with an innovative technique for the detection of disturbing loads in distorted power systems. The technique is a single-point strategy based on a comparison among different ldquononactiverdquo power quantities already proposed in the literature, which are measured at the same metering section. In this paper, the effectiveness of the strategy is discussed, which also considered the errors of the measurement transducers; the analysis is supported by simulation tests, which were carried out on both a simple single-phase system and an IEEE standard three-phase test power system. The latter was used by other authors as a benchmark system for the analysis of multipoint measureme…
An enhanced approach based on IEEE 1459 for the detection of disturbing loads in distorted and unbalanced three-phase power systems
2009
This paper presents an enhanced approach for the detection of disturbing loads in distorted and/or unbalanced three-phase power systems in both cases of three and four-wires. It is based on the IEEE Std. 1459-2000 effective apparent power resolution and it requires only the separation of the fundamental components of voltage and current from the remaining harmonic content. In the paper, the formulation of the novel approach is given and some simulation results are presented.
STRUCTURAL ANALYSIS OF A POSTERIOR STABILITY TOTAL KNEE JOINT REPLACEMENT
2011
Aim of this work is to compare two different total knee prostheses that differ in the shape of the Polyethylene (PE) insert, trying to optimize the shape of the best one, in order to reduce the stress peaks. The study procedure has been divided into the following steps. First step has been the three-dimensional shape acquisition of the two prostheses by means of a COMET5 3D scanner. The morphology of two prototypes of the prostheses has been acquired by elaborating multiple Moirè fringe pattern projected on their surfaces. Second step consisted of the manipulation of these data in a CAD module, that is the interpolation of raw data into parametric surfaces, reducing singularities due to the…
Validation of a method to measure total spontaneous physical activity of sedentary and voluntary running mice
2014
Running wheels are commonly used to stimulate physical activity of mice. To control the effects of physical activity on study results, it is important to measure the total activity (all movements) of both sedentary and running wheel stimulated mice.Because there was a lack of a validated system, we built a force-plate based system specifically for this purpose. The validity of the system and its variables (activity index, activity time and distance) were tested in calibration measurements and in situ by measuring the activity of eight mice both with and without running wheels. Four mice served as sedentary controls. Activity index adds changes in vertical reaction forces induced by moving m…
Non associative damage interface model for mixed mode delamination and frictional contact
2019
Abstract The present paper proposes a new interface constitutive model based on the non-associative damage mechanics and frictional plasticity. The model is developed in a thermodynamically consistent framework, with three independent damage variables. The non associative flow rules drive the concurrent evolution of the three damage variables. The interface model provides two independent values for the mode I fracture energy and the mode II fracture energy and it is able to accurately reproduce arbitrary mixed mode fracture conditions. The model can also take into account the presence of frictional effects both at the fully debonded zones and at the partially debonded ones. The experimental…
Noise levels of a track-laying tractor during field operations in the vineyard
2013
Noise in agriculture is one of the risk factors to be taken into account in the assessment of the health and safety of workers; in particular, it is known that the tractor is a source of high noise. The Italian Low Decree 81/2008 defined the requirements for assessing and managing noise risk identifying a number of procedures to be adopted at different noise levels to limit workers exposure. This paper concerns the analysis of the noise risk arising from the use of a tracklaying tractor during field operations carried out in the vineyard. The objective of this study was to evaluate the noise level that comes close to the ear of the operator driving the tractor measuring the values of equiva…
Mapping of penetrometer resistance in relation to tractor traffic using multivariate geostatistics
2007
Abstract The traffic of agricultural machines can cause soil compaction and high variability of soil structure, both along normal lines and along those parallel to the field plane. The aim of this work was to investigate the potential of an electronic penetrometer, a GPS, a GIS and geostatistical techniques for mapping soil compaction. In July 2003 soil cone penetrometer resistance was measured using a semi-automatic electronic penetrometer in a sandy-silt soil (Vertic Xerochrept) of inland Sicily where a three-year rotation wheat ( Triticum durum Desf.)–wheat–tomato ( Solanum lycopersicum L.) was practiced. The measurements were carried out along three parallel 3-m long transects, from the…
The city under electrodes : from the measure to the evaluation of traffic air pollution : towards a multi-agent simulation of urban road traffic
2016
Based on surveys, traffic is constructed from assumptions about the relationship between origins and destinations. In order to rebuild a road traffic wich would be closer to observation and on a wider set of road sections, it appears interesting to use counting data from urban sensors : this is our starting point of view. The insertion of these in-situ dataset in the road traffic measurement provides the opportunity to experience the potential of sensors to estimate Traffic Air Pollution (TAP) levels at the intraurban scale. However, this requires to change the nature of these estimation, here through the construction of a model of multi-agents simulation, in order to extract more informati…