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A
Cardoso, T., P. Pereira, V. Fernaao Pires, and J. F. Martins, "Android-based m-learning remote system for mobile power quality assessment in large buildings with renewable energies", Power Engineering, Energy and Electrical Drives (POWERENG), 2015 IEEE 5th International Conference on, Riga, Latvia, pp. 431-434, May, 2015. Abstract

Power Quality is a generic term focusing on several issues, going from reliability to the quality of service provided by the energy supplier. It addresses limiting aspects such as harmonic distortion, flicker, sags, swells and transients... It is important for the students to understand the differences between the large amounts of events that fit into poor power quality category. Moreover it is important for them to analyze real time non-laboratory events. To provide this experience to the students this paper presents a remote m-learning experimental system where several types of poor power quality events can be tested. The developed system is based on a power quality analysis distributed network and can be remotely accessed from a remote computer or smart phones.

Mar, A., F. Monteiro, P. Pereira, and J. Martins, "An Application to Improve Smart Heritage City Experience", Advances in Digital Cultural Heritage, Cham, Springer International Publishing, pp. 89–103, 2018. Abstract

Nowadays technologies relate to so many aspects in our daily life that makes society eager for more and more ways of using it. To keep up with this new technological world, all economic sectors, from industry to services, are trying to adapt their products into this new reality. Presently, cultural heritage is already a field where the application of technology allows a static site to be converted into an intelligent environment, with detailed information about a specific monument or historical place, becoming more interesting, not only for local habitants, but also for tourists. This paper describes an application that allows tourists, managers and historical sites' habitants to experience a completely new way of discovering those places, offering a visit with detailed real-time information taking into account their personal interests. Tourists will have at their disposal a full set of optimized routes, combining their interests with their visiting time.

E
Jorge, A., J. Guerreiro, P. Pereira, J. Martins, and L. Gomes, "Energy Consumption Monitoring System for Large Complexes", Doctoral Conference on Computing, Electrical and Industrial Systems, DoCEIS 2010, vol. 314, Costa de Caparica - Portugal, Springer Boston, pp. 419-426, 2010. Abstract

This paper describes the development of an open source system for monitoring and data acquisition of several energy analyzers. The developed system is based on a computer with Internet/Intranet connection by means of RS485 using Modbus RTU as communication protocol. The monitoring/metering system was developed for large building complexes and was validated in the Faculdade de Ciências e Tecnologia University campus. The system considers two distinct applications. The first one allows the user to verify, in real time, the energy consumption of any department in the complex, produce load diagrams, tables and print, email or save all available data. The second application keeps records of active/reactive energy consumption in order to verify the existence of some anomalous situation, and also monthly charge energy consumption to each corresponding department.

I
Paiva, L., P. Pereira, B. Almeida, P. Maló, J. Hyvärinen, K. Klobut, V. Dimitriou, and T. Hassan, "Interoperability: A Data Conversion Framework to Support Energy Simulation", Sustainable Places 2017, vol. 1, no. 7, 2017. Abstract

In this paper an interoperability solution is proposed, aiming to go from (building) construction models to energy simulation. Moreover, the energy simulation results will feed the KPI’s analysis of a designed building. The proposed solution will be used to translate different data formats allowing the communication between different systems in an automated environment. The solution presented in this paper exploits the concept of Plug’n’Interoperate (PnI), that is supported by the principle of self-configuration as to automate, as much as possible, the configuration and participation of systems into a shared interoperability environment. In order to validate this approach two different scenarios were taken into account, translating from a CAD (Computer- Aided Design) model data format to an energy simulation data format.

N
Martins, J. F., P. Pereira, A. J. Pires, and V. F. Pires, "A new teaching tool to enhance power quality assessment", Industrial Electronics Society, IECON 2015 - 41st Annual Conference of the IEEE, Yokohama, Japan, IEEE-IES, pp. 004158-004162, 9-12 Nov., 2015. Abstract

The study and assessment of Power Quality issues is nowadays a very important subject, particularly regarding Cyber-physical and Industrial Agents based systems, which are extremely sensitive to Power Quality disturbances. Giving students or engineers practical experience in this field requires a large investment from teaching institutions. This paper presents a laboratory device that emulates Power Quality disturbances in order to provide the required experimental expertize in the subject. It addresses limiting aspects such as harmonic distortion, flicker, sags, swells and transients. The developed system presents a good opportunity for technicians, even without deep knowledge on the field of power quality, to learn basic principles and be able to identify Power Quality events. Since the system is based on real data, represents a valuable approach giving trainees practical knowledge on the field.

P
Cardoso, T., P. Pereira, V. Fernao Pires, and J. F. Martins, "Power quality and long life education", Industrial Electronics (ISIE), 2014 IEEE 23rd International Symposium on, Istanbul - Turkey, pp. 2224 - 2228, 2014/06. Abstract

This paper presents a remote laboratory linked with mobile devices for real data analysis on the field of power quality. A global system was developed from the power quality analyzer into the human machine interface devoted to the m-learning system. This m-learning system is intended to be used in a long life learning perspective. The developed remote laboratory is a good opportunity for people, even without deep knowledge on the field, to learn power quality principles in an applied way. Since the system is based on real data, is a good approach to give trainees practical knowledge on the field.

R
Pina, J. M., D. Inacio, G. Luis, J. M. Ceballos, P. Pereira, J. Martins, M. Ventim-Neves, A. Alvarez, and A. L. Rodrigues, "Research and Development of Alternative Concepts in HTS Machines", Applied Superconductivity, IEEE Transactions on, vol. 21, no. 3, pp. 1141 -1145, june, 2011. 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' 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' number approach, is applied to a superconducting hysteresis disk motor. All these concepts are being investigated and simulation and experimental results are presented.

Marouani, H., A. Sallem, M. Chaoui, P. Pereira, and N. Masmoudi, "A Robustness Study of Metaheuristics to the Optimal Design of RF Integrated Inductors", 2018 15th International Multi-Conference on Systems, Signals Devices (SSD), pp. 1459-1464, March, 2018. Abstract

In this paper, three metaheuristics are investigated to optimize RF Integrated Inductors; namely Differential Evolution (DE) from the field of evolutionary computation, Gravitational Search Algorithm (GSA) based on the law of gravity and mass interactions and Particle Swarm Optimization (PSO) inspired by swarm behaviors in nature. A particular interest is given to the optimization of RF Integrated Inductors. Performances in terms of optimum quality and computing time of the metaheuristics are checked via three test functions and one application that consist of optimizing performances of characterize integrated inductors based on the double$π$-model.

S
Amorim, M., A. Mar, F. Monteiro, S. Sylaiou, P. Pereira, and J. Martins, "Smart Tourism Routes Based on Real Time Data and Evolutionary Algorithms", Digital Heritage. Progress in Cultural Heritage: Documentation, Preservation, and Protection, Cham, Springer International Publishing, pp. 417–426, 2018. Abstract

Tourism is an industry that has been growing rapidly in the last few years and it is expected that it will continue to grow. Due to the evolution of technology, mobile applications are being increasingly used in all kinds of industries, being one of them tourism. Presently there are already a few mobile applications used to increase the experience of the user when visiting a place, but these mobile applications lack some important features. This paper describes the development of a mobile application with integrated routing algorithms used to increase the experience of the tourists when visiting the city of Avila, Spain. The tourist will have at their disposal real time information about all the monuments available for visit, a full set of predefined circuits with different visit times and degrees of difficulty and also the possibility to create an optimized or personalized circuit combining the user preferences such as visiting time and number of monuments to visit.

Ramos, N. R., P. Pereira, and J. F. Martins, "Smart-meter in power quality", 2017 International Young Engineers Forum (YEF-ECE), pp. 42-46, 5 May, 2017. Abstract

In this paper, an innovative approach for monitoring home electric power quality indicators is presented. Using an electric power analysis device (for this work purpose it will be a smart-meter) and a personal computer it is proved that it is possible to monitor and register electric power quality anomalies, such as long interruptions, voltage dips/swells and frequency oscillations. Through an application developed in Java, a user can view real-time electric parameters, check for electric power quality anomalies and assess load diagram of previous days. Experimental results regarding the application performance are also presented with the respective conclusions.

Inacio, D., J. Murta Pina, P. Pereira, A. Pronto, M. Ventim Neves, and A. Alvarez, "Study of an axial flux disc motor with superconductor rotor", Compatibility and Power Electronics (CPE), 2015 9th International Conference on, Costa de Caparica, Portugal , pp. 488-493, June, 2015. Abstract

The integration of high temperature superconductors (HTS) in electrical machines potentially allows reduction in devices dimensions or performance improvement for the same active volume, when compared with their conventional ones. The use of polycrystalline HTS samples allows big bulk samples. An axial disc motor with HTS material or conventional aluminium in the rotor and conventional armature has been designed and developed. This paper describes simulations and laboratory experiments performed at liquid nitrogen temperature (77 K) in order to analyze the motor's behaviour and its electromechanical characteristics and to define an electric equivalent circuit that allows describing its operation. In order to evaluate the superconducting quality of the bulks and flux pinning phenomena, Hall probe mapping system was performed in order to define the field profiles at 77 K for different polar configurations. The analysis of the obtained results allows confirm the flux pinning phenomena, being the entire rotor magnetized and conclude that the motor with the HTS rotor behaves as a conventional hysteresis motor even though with a different nature, while the motor with aluminium rotor behaves as a conventional induction motor. In asynchronous regime, the HTS motor exhibits a constant torque, higher than the conventional aluminium one. For both cases, the developed torque is proportional to the poles pairs.

Pereira, P., and J. Martins, "Sustainable Heritage Management Towards Mass Tourism Impact: the HERIT-DATA project", 9th International Conference on Intelligent Systems IS’18, Madeira - PT, IEEE, 25-27 Sep., 2018. Abstract

Although tourism is a major engine of economic growth, it also creates a burden hard to manage, and has a great impact on the conservation of the heritage. The HERIT-DATA project aims to reduce the impact of human activities, related to tourism, on cultural heritage, with a special focus on two kind of cultural destinations that can benefit from and be affected by mass tourism: Old towns and places of specific cultural heritage or archaeological interest for visitors, including UNESCO World Heritage Sites. In that framework, HERIT-DATA plans to develop of a sustainable and responsible tourism management towards cultural heritage in MED regions, in particular by taking advantage of technology and innovation in management tools (Smart Cities), as well as other policy and social measures.

Francisco, R., P. Pereira, and J. Martins, "Sustainable Housing Techno-Economic Feasibility Application", Doctoral Conference on Computing, Electrical and Industrial Systems, DoCEIS 2011, vol. 349, Costa de Caparica - Portugal, Springer Boston, pp. 445-454, 2011. Abstract

The high prices currently achieved in the acquisition of non-renewable energy for electricity production and the low levels of energy efficiency in the housing sector are the national situation, which leads the Portuguese government to encourage the acquisition, the installation and the use of technologies which exploit indigenous and renewable energy. This study presents an application that was developed in order to help the citizen in his decision to invest in renewable technologies in their homes. The application is able to elaborate an economic analysis based on the selected type of renewable technology, providing the user with the knowledge of benefits and the annual costs involved in the system that he selected. This tool aims at facilitating the interaction of any user with such technologies and it can be used as a helpful tool to support the decision of investment in such systems.

T
Noack, F., P. Katranuschkov, R. Scherer, V. Dimitriou, S. K. Firth, T. M. Hassan, N. Ramos, P. Pereira, P. Maló, and T. Fernando, "Technical challenges and approaches to transfer building information models to building energy", Proceedings of ECPPM 2016: CRC Press, pp. 355-362, 2016/08/15. Abstract

The complex data exchange between architectural design and building energy simulation constitutes the main challenge in the use of energy performance analyses in the early design stage. The enhancement of BIM model data with additional specific energy-related information and the subsequent mapping to the input of an energy analysis or simulation tool is yet an open issue. This paper examines three approaches for the data transfer from 3D CAD applications to building performance simulations using BIM as central data repository and points out their current and envisaged use in practice. The first approach addresses design scenarios. It focuses on the supporting tools needed to achieve interoperability given a 74 wide-spread commercial BIM model (Autodesk Revit) and a dedicated pre-processing tool (DesignBuilder) for EnergyPlus. The second approach is similar but addresses retrofitting scenarios. In both workflows gbXML is used as the transformation format. In the third approach a standard BIM model, IFC is used as basis for the transfer process for any relevant lifecycle phase.

Delgado-Gomes, V., J. A. Oliveira-Lima, J. F. Martins, C. Lima, and P. Pereira, "Towards to a Web Service alert software system for standard electrical protective devices", Intelligent Engineering Systems (INES), 2012 IEEE 16th International Conference on, Lisbon, Portugal, pp. 197 -201, june, 2012. Abstract

Electrical Protective Devices are key elements in the electrical network. Their purpose is to perform fault detection in electric power systems, by analysing power system voltages and currents. In order to achieve a more centralized control, protective devices can be connected using Web Services through a Service-Oriented Architecture (SOA) approach. This work targets planning and specification of a mapping between Abstract Communication Service Interface (ACSI) Reporting and Device Profile for Web Services (DPWS) Eventing to achieve a better protective electrical devices control, obtaining an event based alert software system, replacing conventional polling-based systems.

V
Murta-Pina, J., P. Pereira, J. M. Ceballos, A. Alvarez, N. Amaro, A. Pronto, J. Silva, and P. Arsenio, "Validation and Application of Sand Pile Modeling of Multiseeded HTS Bulk Superconductors", Applied Superconductivity, IEEE Transactions on, vol. 25, no. 3, pp. 1-5, June, 2015. AbstractWebsite

Sand pile and Bean models have already been applied to describe single grain HTS bulks. An extension to that approach was used to model multiseed bulks, needed for several practical applications as electric motors or flywheels with superconducting bearings. The use of genetic algorithms was then proposed to determine intra- and intergrain current densities, and application to two and three seeds samples using trapped flux experimental measurements was exemplified. However, this model assumed some simplifications, as equal properties in grain boundaries between neighboring grains. In this paper an extension to this methodology is proposed and evaluated by analyzing measurements performed in plans at different distances from surfaces of samples with three seeds. Discussion of its influence on a practical application is also explored.

W
Afonso, M., P. Pereira, and J. Martins, "Weather Monitoring System for Renewable Energy Power Production Correlation", Doctoral Conference on Computing, Electrical and Industrial Systems, DoCEIS 2011, vol. 349, Costa de Caparica - Portugal, Springer Boston, pp. 481-490, 2011. Abstract

This work describes the development of a system designed for renewable power generation integration. It continuously acquires wind, solar and temperature data, which is automatically correlated with energy parameters, obtained from renewable energy systems. The developed system was installed in an urban building equipped with photovoltaic cells and wind renewable generation. To validate the developed application, it was analyzed data of a wind generator and a set of photovoltaic panels, installed near to the weather station. The developed application allows, in addition to the acquisition of weather and energy data, their continuous monitoring and correlation through a graphical user interface, providing a friendly interactivity with the user.