Search results for "AREs"

LPV models: Identification for gain scheduling control

2001

In this paper the use of discrete-time Linear Parameter Varying (LPV) models for the gain scheduling control and identification methods for non-linear or time-varying system is considered. We report an overview on the existing literature on LPV systems for gain scheduling control and identification. Moreover, assuming that inputs, outputs and the scheduling parameters are measured, and a form of the functional dependence of the coefficients on the parameters is known, we show how the identification problem can be reduced to a linear regression so that a Least Mean Square and Recursive Least Square identification algorithm can be reformulated. Our methodology is applied for the identificatio…

A novel implicit correlation for the operative temperature of a PV panel

2012

Abstract The operating temperature of a commercial PV panel strongly affects the electric power output of the devices. The prediction of the operating temperature therefore plays a central role in the economic and energy assessment of PV systems. The authors propose a new implicit correlation that takes into account the standard weather variables but also the regimen of PV panel in terms of the proximity to the maximum power points. Data coming from an experimental setup were processed by using the least squares technique. To validate the reliability of the correlation, a comparison between expected values and data from other common correlations were done. The results show that the regimen …

Least squares and genetic algorithms for parameter identification of induction motors

2001

Abstract This paper deals with off-line parameter identification of induction motors by means of least square (LS) techniques and genetic algorithms (GA), using stator voltages, stator currents and velocity as input–output data. For analytical identification by LS algorithms, filtering of experimental data is performed by means of anticausal filters. Two models useful for identification are derived in which the products of acceleration and rotor fluxes, usually neglected, are taken into account. The GA-based identification method consists of the determination of the best parameters which match input–output behaviour of the motor. Both methods are investigated and compared by means of experi…

Sensorless control of PMSM by a linear neural network: TLS EXIN neuron

2010

Sensorless vector control applied to the Permanent Magnet Synchronous Motors (PMSMs) is a very challenging subject. It permits obtaining high dinamical performance by exploiting increased reliability and also reduced cost. Among the different methodologies proposed in literature, a model based approach has been proposed here. In particular, the space vector equations of the PMSM have been re-elaborated to permit the use of a Least Squares technique. The problem has been then faced-up to with the so-called TLS EXIN neuron, which is a linear neural network able to solve the TLS problem on-line. Simulation tests have been done on both interior mounted and surface mounted machines.

Relationship between employee involvement and lean manufacturing and its effect on performance in a rigid continuous process industry

2015

Relationship between employee involvement and lean manufacturing and its effect on performance in a rigid continuous process industry DOI: 10.1080/00207543.2014.975852 Juan A. Marin-Garciaa* & Tomas Bonaviab Received: 1 Aug 2013 Accepted: 30 Sep 2014 Published online: 04 Nov 2014 This research aims to empirically test the effect of employee involvement on lean manufacturing (LM), and the effect of LM on production outcomes. Employee involvement is operationalised through four related variables: empowerment, training, contingent remuneration and communication. The effects are tested by recording management perceptions in a different industrial sector from those usually studied in previous re…

Ricordo di Enrico Mazzarese Fardella

2018

Una riflessione, con ampi risvolti scientifici, sulla figura e la produzione di Enrico Mazzarese Fardella, Professore di Storia del diritto italiano all'Università di Palermo.

La necrópolis occidental de la Valencia romana

1996

Ubicada en una pequeña elevación del terreno y junto a uno de los principales ejes viarios de la ciudad (calle Cavallers/Quart), prolongación del decumanus maximus, se localiza la necrópolis occidental de Valentia. Cronológicamente abarca desde mediados del siglo I a.C. hasta el siglo III-IV d.C. Hay que destacar que la práctica de la inhumación es anterior a la incineración y casi exclusiva, en contra de la tendencia predominante. Este hecho lo hemos puesto en relación con la raíz centro-itálica de los fundadores de Valentia y el mantenimiento de sus tradiciones de origen.

Los cementerios de época visigoda

1996

The COVID-19 Impact on Bucharest Stock Exchange. The First Six Months

2020

Abstract The first case of coronavirus was registered in Romania on February 26. From this moment, Romania has become “infected”, just like the whole world, and the economy has suffered milder or more severe symptoms, depending on the activity field. Four months have passed since then, during which in Romania, the effects of the health crisis overlapped with a tense political situation, in an unfavorable economic context. Once the COVID-19 hits each country, the economic effects started to become visible in all the world’s financial markets, the financial market being among the first to suffer the impact of the COVID-19 crisis. This paper analyzes how the financial market in Romania was aff…

Board of director attributes: effects on financial performance in SMEs

2021

This paper analyses the relationship between board of director (BoD) attributes and financial performance in small and medium-sized enterprises (SMEs). Although SMEs are the backbone of world economies, most studies on this relationship focused on large companies and did not consider many typical or recommended processes and activities carried out by SME BoDs. We monitored a set of variables related to BoD attributes such as composition, characteristics, structure and processes for 184 Italian SMEs along with their financials over a 4-year period (2014–2017). We controlled for enterprise-specific characteristics such as annual sales growth, assets value, sales turnover, leverage, com pany s…