Joao Afonso - Academia.edu (original) (raw)

Papers by Joao Afonso

World Electric Vehicle Journal, 2010

In this work is proposed the design of a system to create and handle an Electric Vehicle (EV) com... more In this work is proposed the design of a system to create and handle an Electric Vehicle (EV) community, based on social networks collaborative approach and a credit mechanism to incentive participation and divide profits. This system is part of a V2G (Vehicle-to-Grid) module that allows EV owners to be aggregated in communities and participate in the electricity market. With this system it is possible for the EV owners to win money while the EVs are parked and plugged, delivering back to the electrical grid part of the energy stored in the batteries, increasing the attractiveness of EVs.

Proceedings of the Second International Conference on e-Business and Telecommunication Networks, 2005

In this work we propose a computer platform that aims to unify the tasks of monitoring, diagnosin... more In this work we propose a computer platform that aims to unify the tasks of monitoring, diagnosing, error detection, alarm management and intrusion detection associated with the administration of a computer network and related critical services. As main objective, we intend to develop a user-intuitive program that does not require specialized computer skills from the operators in order to assume full responsibility for the system. Open-source solutions were used, whenever possible, namely for server operating systems, application development tools, database engine and integrated Web solution. The project started by studying the existing solutions, exploring their strengths and shortcomings and iteratively defining the specific requirements to be implemented. The development phase was conceptually divided in three different levels: the agents and connectors collecting the data from the different areas being monitored; the database engine, cataloguing the information and the Web Interface (Security Portal) that allows the management of all functionalities and guarantees the operationability of the solution. An alarm management tool should also be developed permitting, according to programmed warnings for certain malfunctions, trigger the warning messages through the predefined medium-E-Mail, SMS (short message service) or IM (instant messaging), using a Unified Messaging (UM) solution. According to the defined specifications, the solution to be implemented was designed and a functional analysis was created. Finally the projected solution was implemented and applied to a case studythe Department of Fisheries Inspection from the General-Directorate of Fisheries and Aquiculture. The preliminary results from the reliability and user-friendliness tests were very positive and a decision was made to move into the production phase. The platform was developed in line with current accessibility requirements and can be operated / consulted by users with disabilities.

Modern power converters (power supplies) at CERN use proprietary controls hardware, which is inte... more Modern power converters (power supplies) at CERN use proprietary controls hardware, which is integrated into the wider control system by software device servers developed specifically for the CERN environment, built using CERN libraries and communication protocols. There is a growing need to allow other HEP laboratories to make use of power converters that were originally developed for CERN and, consequently, a desire to allow for their efficient integration into control systems used at those laboratories, which are generally based upon either of the EPICS and Tango frameworks. This paper gives an overview of power converter equipment and software currently being provided to other laboratories through CERN's Knowledge and Technology Transfer program and describes differences identified between CERN's control system model and that of EPICS, which needed to be accounted for. A reference EPICS implementation provided by CERN to other laboratories to facilitate integration of th...

This paper uses typed linear algebra (LA) to represent data and perform analytical querying in a ... more This paper uses typed linear algebra (LA) to represent data and perform analytical querying in a single, unified framework. The typed approach offers strong type checking (as in modern programming languages) and a diagrammatic way of expressing queries (paths in LA diagrams). A kernel of LA operators has been implemented so that paths extracted from LA diagrams can be executed. The approach is validated and evaluated taking TPC-H benchmark queries as reference. The performance of the LA-based approach is compared with popular database competitors (PostgreSQL and MySQL).

Abstract. This paper describes the development of a low-cost digital system used for power qualit... more Abstract. This paper describes the development of a low-cost digital system used for power quality monitoring and power management. The system uses voltage and current Hall sensors, a standard data acquisition board, and has its processing system based in LabVIEW™, running on a regular PC. The system acquires data continuously, and storage in files the events that result from the anomalies detected in the monitored power system. Several parameters related to power quality can be analysed through 6 different applications: “Scope and THD”, “Strip Chart”, “Wave Shape”, “Sags and Swells”, “Classical Values ” and “p-q Theory Values”. The acquired information can be visualized in tables and/or in charts. It is also possible to generate reports in HTML format. In this format, the reports can be sent directly to a printer, can be embedded in other software applications, or can be accessed through the Internet, using a web browser. It is also shown the potential of the developed system, name...

Transactions on Engineering Technologies, 2018

This chapter presents the development and test of an intra-vehicular wireless sensor network (IVW... more This chapter presents the development and test of an intra-vehicular wireless sensor network (IVWSN), based on Bluetooth Low Energy (BLE), designed to present to the driver, in real-time, information collected from multiple sensors distributed inside of the car, using a human-machine interface (HMI) implemented on an Android smartphone. The architecture of the implemented BLE network is composed by the smartphone, which has the role of central station, and two BLE modules (peripheral stations) based on the CC2540 systemon-chip (SoC), which collect relevant sensor information from the battery system and the traction system of a plug-in electric car. Results based on an experimental performance evaluation of the wireless network show that the network is able to satisfy the application requirements, as long as the network parameters are properly configured taking into account the peculiarities of the BLE data transfer modes and the observed limitations of the BLE platform used in the implementation of the IVWSN.

This paper presents an Android-based mobile app designed to provide real time context aware publi... more This paper presents an Android-based mobile app designed to provide real time context aware public transportation information and advice to its users through the combination of the user’s preferences and geographic context with data retrieved from a public transportation information system called XTraN Passenger. Thus, this mobile app contributes to fulfill the necessities of the passengers, and also provides an incentive for people to use the public transportation infrastructure more frequently. The proposed mobile app allows the users to benefit from the access to real time public transportation data in a simple and intuitive way. The validation of the features and operation of the developed app was assessed with results from use cases and real-world experimental tests using public transportation data from a Brazilian bus fleet operator.

Energies, 2021

The decentralization in the electrical power grids has gained increasing importance, especially i... more The decentralization in the electrical power grids has gained increasing importance, especially in the last two decades, since transmission system operators (TSO), distribution system operators (DSO) and consumers are more aware of energy efficiency and energy sustainability issues. Therefore, globally, due to the introduction of energy production technologies near the consumers, in residential and industrial sectors, new scenarios of distributed energy resources (DER) are emerging. In order to guarantee an adequate power management in the electrical power grids, incorporating producers, consumers and producers-consumers (prosumers) together, it is important to adopt intelligent systems and platforms that allow the provision of information on energy consumption and production in real time, as well as for obtaining a fair price for the sale and purchase of energy. In this paper, we analyze the literature to identify the appropriate solutions to implement a decentralized electrical po...

This paper presents the development and test of an intra-vehicular system, based on Bluetooth Low... more This paper presents the development and test of an intra-vehicular system, based on Bluetooth Low Energy (BLE), designed to present to the driver, in real-time, information collected from multiple sensors distributed inside of the car, using an Android smartphone. The architecture of the implemented BLE network is composed by the smartphone, which has the role of central station, and two BLE modules (peripheral stations) based on the CC2540 system-on-chip, which collect relevant sensor information from the battery system and the traction system of an electric car. Results based on an experimental performance evaluation of the wireless network show that the network is able to satisfy the application requirements, as long as the network parameters are properly configured taking into account the peculiarities of the BLE data transfer modes and the limitations of the BLE platform.

IECON 2018 - 44th Annual Conference of the IEEE Industrial Electronics Society, 2018

This paper presents the development and test of an Internet of Things (IoT) system for monitoring... more This paper presents the development and test of an Internet of Things (IoT) system for monitoring and control of electric vehicles. The IoT architecture, which was developed using the Firebase platform, allows the synchronization of the vehicles' data to the online server, as well as the access to the data outside of the vehicle, though the Internet. The smart charging system proposed in this paper allows the control of the electric vehicle's battery charging current in real time, based on the demand at the residence (home current), which is measured using a residential wireless sensor network (WSN). An Android mobile app was developed to access the vehicle's data. This app communicates with the wireless sensor nodes of an intravehicular wireless sensor network (IVWSN), which was developed using the Bluetooth Low Energy (BLE) protocol. A real time notification system was also implemented to alert users about certain events, such as low battery and full battery charge. The main features of the proposed IoT system are validated through experimental results.

Electronics, 2018

This paper describes the development and implementation of an electronic platform for energy mana... more This paper describes the development and implementation of an electronic platform for energy management in public buildings. The developed platform prototype is based on the installation of a network of wireless sensors using the emerging Long Range (LoRa) low power long-range wireless network technology. This network is used to collect sensor data, which is stored online and manipulated to extract knowledge and generate actions toward energy saving solutions. In this process, gamification approaches were used to motivate changes in the users’ behavior towards more sustainable actions in public buildings. These actions and the associated processes can be implemented as public services, and they can be replicated to different public buildings, contributing to a more energy-sustainable world. The developed platform allows the monitoring and management of the heating/cooling, electric power consumption, and lighting levels. In order to validate the proposed electronic platform, sensor ...

IEEE Transactions on Industrial Informatics, 2015

This paper presents the project of a Mobile Cockpit System (MCS) for smartphones, which provides ... more This paper presents the project of a Mobile Cockpit System (MCS) for smartphones, which provides assistance to Electric Bicycle (EB) cyclists in Smart Cities' environment. The presented system introduces a mobile application (MCS App) with the goal to provide useful personalized information to the cyclist related with the EB's use, including EB range prediction considering the intended path, management of the cycling effort performed by the cyclist, handling of the battery charging process and the provisioning of information regarding available public transport. This work also introduces the EB cyclist profile concept, which is based on historical data analysis previously stored in a database and collected from mobile devices sensors. From the tests performed, the results show the importance of route guidance, taking into account the energy savings. The results also show significant changes on range prediction based on user and route taken. It is important to say that the proposed system can be used for all bicycle in general.

There is no doubt that one of the most critical components of the Internet is the DNS-Domain Name... more There is no doubt that one of the most critical components of the Internet is the DNS-Domain Name System. In this paper, we propose a solution to strengthen the security of DNS servers, namely those associated with Top Level Domains (TLD), by using a system that identifies patterns of potentially harmful traffic and isolates it. The proposed solution has been developed and tested at FCCN, the TLD manager for the .PT domain. The system consists of network sensors that monitor the network in real-time and can dynamically detect, prevent, or limit the scope of the attempted intrusions or other types of attacks to the DNS service, thus improving it's global availability.

Electric Vehicles (EV) are being introduced in the market, however the reduced energy storage cap... more Electric Vehicles (EV) are being introduced in the market, however the reduced energy storage capacity of their batteries and the lack of a high density charging infrastructure, limits their autonomy range. In order to overcome this limitation, we propose the development of a new solution for EV drivers that enables to travel longer distances. This is achieved by integrating some components of the cooperative transport infrastructure, as EV battery charging systems and public transports systems, and by increasing the driving autonomy through energy consumption reduction, achieved by driving efficiency increase. The integration with the charging infrastructure allows planning the journey of the driver, considering the position of charging points, and booking a charging point for a specific time period in order to perform the battery charging. Therefore, the distance that the driver can drive comfortably, without fearing running out of battery, is increased. The integration of the EV with public transports systems allows extending the travel distance beyond the EV drive autonomy, given by the storing capacity of vehicle's battery. The supplying of information on availability, schedule and price of public transports allows planning the journey of the driver, using the EV and public transportation in a complementary way, through functions like car parking booking (and charging) and ticket buying.

2003 IEEE International Symposium on Industrial Electronics ( Cat. No.03TH8692), 2003

This paper presents the development of a low-cost digital system useful for power quality monitor... more This paper presents the development of a low-cost digital system useful for power quality monitoring and power management. Voltage and current measurements are made through Hall-effect sensors connected to a standard data acquisition board, and the applications were programmed in LabVIEW™, running on Windows in a regular PC. The system acquires data continuously, and stores in files the events that result from anomalies detected in the monitored power system. Several parameters related to power quality and power management can be analyzed through 6 different applications, named: "Scope and THD", "Strip Chart", "Wave Shape", "Sags and Swells", "Classical Values" and "p-q Theory". The acquired information can be visualized in tables and/or in charts. It is also possible to generate reports in HTML format. These reports can be sent directly to a printer, embedded in other software applications, or accessed through the Internet, using a web browser. The potential of the developed system is shown, namely the advantages of virtual instrumentation, regarding to flexibility, cost and performance, in the scope of power quality monitoring and power management.

International Journal of Distributed Sensor Networks, 2012

The security problems that outbreak network services today are increasing at a dramatic pace espe... more The security problems that outbreak network services today are increasing at a dramatic pace especially with the unceasing improvement of network transmission rates and the sheer amount of data exchanged. This translates not only more incidents but also new types of attacks with network incidents becoming more and more frequent. A significant part of the attacks occurs at Top Level Domains (TLDs) who have the assignment of ensuring the correct functioning of Domain Name System (DNS) zones. The proposed solution has been developed and tested at FCCN (Foundation for National Scientific Computing), the TLD manager for the .PT domain. The system consists of network sensors that monitor the network in real-time and can dynamically detect, prevent, or limit the scope of the attempted intrusions or other types of attacks to the DNS service, thus improving its global availability.

Power Quality Issues, 2013

2011 IEEE 3rd International Conference on Communication Software and Networks, 2011

In this work is proposed the design of a system to create and handle Electric Vehicles (EV) charg... more In this work is proposed the design of a system to create and handle Electric Vehicles (EV) charging procedures, based on intelligent process. Due to the electrical power distribution network limitation and absence of smart meter devices, Electric Vehicles charging should be performed in a balanced way, taking into account past experience (spread in a social network). In order to allow information exchange and to help user mobility, it was also created a mobile application to assist the EV driver on these processes. This proposed Smart Electric Vehicle Charging System uses Vehicle-to-Grid (V2G) technology, in order to connect Electric Vehicles and also renewable energy sources to Smart Grids (SG). This system also explores the new paradigm of Electrical Markets (EM), with deregulation of electricity production and use, in order to obtain the best conditions for commercializing electrical energy.