@conference {OA5058, title = {Towards an energy model for supporting real time building energy management}, booktitle = {2012 IEEE 16th International Conference on Intelligent Engineering Systems (INES)}, year = {2012}, note = {n/a}, pages = {203{\textendash}208}, abstract = {

Building energy management may simultaneously integrate multiple energy areas and sources of information. The coordination of synergies allow better-informed decisions, such as performing forecasts and adjustments of energy production and storage, while adapting electrical loads to off-peak times, when energy rates are lower. This work targets the improvement and optimization of energy management operations in buildings and large complexes, by introducing a conceptual model for supporting real-time advanced reasoning and inference towards efficient energy management.

}, url = {http://oa.uninova.pt/5058/}, author = {Oliveira-Lima, Jose A. and Jo{\~a}o F. Martins and Lima, Celson and Delgado-Gomes, Vasco and Jo{\~a}o Pina and Grzegorz Benysek} } @article {OA4734, title = {Experimental Characterization of a Conventional (Aluminum) and of a Superconducting (YBCO) Axial Flux Disc Motor}, journal = {IEEE Transactions on Applied Superconductivity}, year = {2011}, note = {n/a}, month = {January}, abstract = {

An equivalent model and electromechanical characteristics for the disk motor was obtained based on the Steinmetz parameters. This paper describes a series of tests conducted on an axial flux motor, equipped with an aluminum rotor disc and an YBCO high temperature superconducting rotor disc, at liquid nitrogen temperature (77 K). The rotating magnetic field was produced by a four-pole, three-phase stator winding, at 50 Hz. At asynchronous permanent regime, Steinmetz-type models are able to describe both motors{\textquoteright} behavior. From the performed tests, the parameters of both motors{\textquoteright} models were deduced. A variable load was used to obtain both motor{\textquoteright}s characteristics (conventional and superconducting). Experimental obtained characteristics of both motors are compared with the ones predicted from parameters{\textquoteright} calculation. The HTS motor provides high efficiency then the conventional ones.

}, url = {http://oa.uninova.pt/4734/}, author = {D In{\'a}cio and Jo{\~a}o Pina and Go{\cn}alo Luis and J. F. Martins and Ventim-Neves, M. and Alfredo Alvarez} } @article {OA5068, title = {Experimental Characterization of a Conventional (Aluminum) and of a Superconducting (YBCO) Axial Flux Disc Motor}, journal = {IEEE Transactions on Applied Superconductivity}, volume = {21}, number = {3}, year = {2011}, note = {n/a}, pages = {1146{\textendash}1150}, abstract = {

An equivalent model and electromechanical characteristics for the disk motor was obtained based on the Steinmetz parameters. This paper describes a series of tests conducted on an axial flux motor, equipped with an aluminum rotor disc and an YBCO high temperature superconducting rotor disc, at liquid nitrogen temperature (77 K). The rotating magnetic field was produced by a four-pole, three-phase stator winding, at 50 Hz. At asynchronous permanent regime, Steinmetz-type models are able to describe both motors{\textquoteright} behavior. From the performed tests, the parameters of both motors{\textquoteright} models were deduced. A variable load was used to obtain both motor{\textquoteright}s characteristics (conventional and superconducting). Experimental obtained characteristics of both motors are compared with the ones predicted from parameters{\textquoteright} calculation. The HTS motor provides high efficiency then the conventional ones.

}, url = {http://oa.uninova.pt/5068/}, author = {David In{\'a}cio and Jo{\~a}o Pina and Go{\cn}alo Luis and Jo{\~a}o F. Martins and M{\'a}rio Neves and Alfredo Alvarez} } @article {OA2534, title = {Research and Development of Alternative Concepts in HTS Machines}, journal = {IEEE Transactions on Applied Superconductivity}, volume = {21}, number = {3}, year = {2010}, note = {n/a}, month = {December}, pages = {1141{\textendash}1145}, publisher = {IEEE}, abstract = {

High temperature superconducting (HTS) machines are recognized to offer several advantageous features when comparing to conventional ones. Amongst these, highlights the decrease in weight and volume of the machines, due to increased current density in conductors or the absence of iron slots{\textquoteright} teeth; or the decrease in AC losses and consequent higher efficiency of the machines, even accounting for cryogenics. These concepts have been already demonstrated and some machines have even achieved commercial stage. In this paper, several alternative approaches are applied to electrical motors employing HTS materials. The first one is an all superconducting linear motor, where copper conductors and permanent magnets are replaced by Bi-2223 windings and trapped flux magnets, taking advantage of stable levitation due to flux pinning, higher current densities and higher excitation field. The second is an induction disk motor with Bi-2223 armature, where iron, ironless and hybrid approaches are compared. Finally, an innovative command strategy, consisting of an electronically variable pole pairs{\textquoteright} number approach, is applied to a superconducting hysteresis disk motor. All these concepts are being investigated and simulation and experimental results are presented.

}, url = {http://oa.uninova.pt/2534/}, author = {Jo{\~a}o Pina and David In{\'a}cio and Gon{\c c}alo Luis and Jos{\'e} M. Ceballos and Pedro Pereira and Martins, Jo{\~a}o and Ventim-Neves, M. and Alfredo Alvarez and A. Le{\~a}o Rodrigues} } @unpublished {OA2137, title = {Electrifica{\c c}{\~a}o de servi{\c c}os prim{\'a}rios em povoados remotos africanos recorrendo a sistemas solares fotovoltaicos (PV)}, year = {2009}, note = {n/a}, month = {July}, publisher = {FCT-UNL}, abstract = {

A presente disserta{\c c}{\~a}o surge pelo interesse em estudar a adequa{\c c}{\~a}o do uso de sistemas solares fotovoltaicos na electrifica{\c c}{\~a}o de servi{\c c}os prim{\'a}rios em povoados remotos nos pa{\'\i}ses Africanos mais carenciados. A abordagem te{\'o}rica tem como objectivo principal reflectir sobre a import{\^a}ncia destas aplica{\c c}{\~o}es intervindo naquelas que s{\~a}o consideradas as maiores dificuldades dos pa{\'\i}ses subdesenvolvidos, ou seja, saneamento b{\'a}sico, servi{\c c}os de sa{\'u}de e meios de comunica{\c c}{\~a}o adequados. Nesse contexto estuda-se a viabilidade de alimentar com energia el{\'e}ctrica produzida localmente unidades sanit{\'a}rias na prov{\'\i}ncia de Sofala (Mo{\c c}ambique). O trabalho exigiu por isso um estudo de caso baseado numa dessas unidades. Mediante a an{\'a}lise das amostras recolhidas para esta investiga{\c c}{\~a}o elaborou-se atrav{\'e}s de ferramentas inform{\'a}ticas um dimensionamento e uma modela{\c c}{\~a}o adequadas ao sistema fotovoltaico a ser implementado. Os resultados obtidos de acordo com os requisitos da unidade sanit{\'a}ria permitiram dimensionar os elementos do sistema bem como, simular hora a hora o seu funcionamento di{\'a}rio ao longo do ano. Uma vez provada a sua viabilidade incluiuse ainda neste trabalho um anteprojecto da instala{\c c}{\~a}o.

}, url = {http://oa.uninova.pt/2137/}, author = {Ricardo Leote}, editor = {M{\'a}rio Neves and Jo{\~a}o Pina} } @article {OA1882, title = {A glass furnace operation system using fuzzy modelling and genetic algorithms for performance optimisation}, journal = {Engineering Applications of Artificial Intelligence}, volume = {16}, number = {7-8}, year = {2003}, note = {n/a}, pages = {681{\textendash}690}, abstract = {

An architecture for the operation of a recuperative-type glass furnace is introduced in this paper. It is based on a hierarchical scheme, with two main parts: process optimisation and process modelling. Process optimisation is carried out by an expert controller, and uses genetic algorithms to solve a multiobjective optimisation problem. Process modelling is performed by a learning system, based on a fuzzy learning-by-examples algorithm. Results of real and simulated experiments with the glass manufacturing process are presented.

}, url = {http://oa.uninova.pt/1882/}, author = {J. Pina and PU Lima} } @unpublished {OA511, title = {Opera{\c c}{\~a}o e Controlo de um Forno de Vidro}, year = {2002}, note = {n/a}, publisher = {IST - Instituto Superior T{\'e}cnico}, abstract = {n/a}, url = {http://oa.uninova.pt/511/}, author = {Jo{\~a}o Pina}, editor = {Pedro Lima} }