Search results for "grid"
showing 10 items of 792 documents
Detection and classification of microcalcifications clusters in digitized mammograms
2005
In the present paper we discuss a new approach for the detection of microcalcification clusters, based on neural networks and developed as part of the MAGIC-5 project, an INFN-funded program which aims at the development and implementation of CAD algorithms in a GRID-based distributed environment. The proposed approach has as its roots the desire to maximize the rejection of background during the analytical pre-processing stage, in order to train and test the neural network with as clean as possible a sample and therefore maximize its performance. The algorithm is composed of three modules: the image pre-processing, the feature extraction component and the Backpropagation Neural Network mod…
Adaptive mesh refinement techniques for high-order shock capturing schemes for multi-dimensional hydrodynamic simulations
2006
The numerical simulation of physical phenomena represented by non-linear hyperbolic systems of conservation laws presents specific difficulties mainly due to the presence of discontinuities in the solution. State of the art methods for the solution of such equations involve high resolution shock capturing schemes, which are able to produce sharp profiles at the discontinuities and high accuracy in smooth regions, together with some kind of grid adaption, which reduces the computational cost by using finer grids near the discontinuities and coarser grids in smooth regions. The combination of both techniques presents intrinsic numerical and programming difficulties. In this work we present a …
A Game Theory Approach and Tariff Strategy for Demand Side Management
2018
Demand side management in smart grid environment with smart meters, renewable energy sources, different kind of consumers etc. is a complex problem. To optimize the problem game theory methodology is used. Game theory approach provide win-win situation between consumers and utilities. Objective of the paper is to find the Nash equilibrium between consumer and utility when utility is supplied through green energy sources. Mathematical modeling of consumption and utilization derived a Nash equilibrium point where consumer and utility both get maximum payoffs. Results shows that energy consumption cost is reduce by applying game theory approach.
The Southern African Power Pool: An Electrifying Project with Untapped Potential
2017
This chapter turns to infrastructure and gives an outstanding analysis of regional electricity cooperation in the SADC within the framework of the Southern African Power Pool (SAPP). The author illustrates the regional power imbalances in terms of national electricity generation and consumption which fuel the SADC countries’ demand for a regional electricity market and an interconnected regional power grid. It becomes clear that the SAPP’s institutional design is strongly influenced by South Africa as the hub of the existing power network and largest electricity producer. Influence by external actors is supportive of regional electricity cooperation since the EU provides funding for the SAP…
Novel Energy Modelling and Forecasting Tools for Smart Energy Networks
2015
A novel Energy Modelling and Forecasting Tool (EMFT) has been adopted for use in the VIM SEN (Virtual Microgrids for Smart Energy Networks) project and this paper gives an insight of the techniques used to provide vital support to the energy market, in particular to energy aggregators. A brief description of one of the test sites where data has been collected for validation of the EMFT will be outlined and some examples shown. The information and predictions will then be used by a decision support system to dynamically adjust energy delivery and consumption, by giving advice to users and operators on actions they can take to obtain a better match between energy supply and demand that increa…
Effects of the Italian financial crisis on the photovoltaic dissemination in a southern city
2013
Abstract The aim of this paper is to estimate how the profitability of grid-connected PV (photovoltaic) systems may vary month by month due to the changes in all parameters involved in the economic evaluation (discount rate, PV electricity selling price, inflation rate, price of PV devices etc.). The effects of these variations were investigated for a district of a city in the South Italy (Palermo). The results of the analysis provided the trend of the actual coverage of the district power demand from June 2010 to August 2012. In particular the load match index, which considers the daily energy demand covered by PV systems, ranged from almost 30% to less than 12%, which is less than the val…
Packing a trunk - Now with a twist!
2005
In an industry project with a German car manufacturer we are faced with the challenge of placing a maximum number of uniform rigid rectangular boxes in the interior of a car trunk. The problem is of practical importance due to a European industry norm which requires car manufacturers to state the trunk volume according to this measure. No really satisfactory automated solution for this problem has been known in the past. In spite of its NP hardness, combinatorial optimization techniques, which consider only grid-aligned placements, produce solutions which are very close to the one achievable by a human expert in several hours of tedious work. The remaining gap is mostly due to the constrain…
Optimal Placements of SVC Devices in Low Voltage Grids with High Penetration of PV Systems
2018
With the increase of load demand and distributed photovoltaic (PV) systems on the electric grid, maintaining the required voltage tolerance at the point delivery (customer homes/businesses) is becoming more challenging for electric power utilities. In a residential neighborhood, the peak load typically occurs in the early evening hours while maximum PV generation occurs during mid day. As a result, the lowest voltage operating points occur in the evening hours; whereas the highest voltage operating point occur during the day, when the PV systems are injecting more power than what is locally consumed. Static VAR Compensators (SVCs) can be used to mitigate voltage violations and smooth out th…
A Virtual Tool for Load Flow Analysis in a Micro-Grid
2020
This paper proposes a virtual tool for load flow analysis in energy distribution systems of micro-grids. The solution is based on a low-cost measurement architecture, which entails low-voltage power measurements in each secondary substation and a voltage measurement at the beginning of the medium voltage (MV) feeder. The proposed virtual tool periodically queries these instruments to acquire the measurements. Then, it implements a backward&ndash
CZT-Based Harmonic Analysis in Smart Grid Using Low-Cost Electronic Measurement Boards
2023
This paper validates the use of a harmonic analysis algorithm on a microcontroller to perform measurements of non-stationary signals in the context of smart grids. The increasing presence of electronic devices such as inverters of distributed generators (DG), power converters of charging stations for electric vehicles, etc. can drain non-stationary currents during their operation. A classical fast Fourier transform (FFT) algorithm may not have sufficient spectral resolution for the evaluation of harmonics and inter-harmonics. Thus, in this paper, the implementation of a chirp-Z transform (CZT) algorithm is suggested, which has a spectral resolution independent from the observation window. T…