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  • Comparison of Semi-structured Data on MSSQL and PostgreSQL
    Publication . Alves, Leandro; Cardoso, Filipe; Oliveira, Pedro; Rocha, Júlio; Wanzeller, Cristina; Martins, Pedro; Abbasi, Maryam
    The present study intends to compare the performance of two Data Base Management Systems, specifically Microsoft SQL Server and PostgreSQL, focusing on data insertion, queries execution, and indexation. To simulate how Microsoft SQL Server performs with key-value oriented datasets we use a converted TPC-H lineitem table. The data set is explored in two different ways, firsts using the key-value-like format and second in JSON format. The same dataset is applied to PostgreSQL DBMS to analyse performance and compare both database engines. After testing the load process on both databases, performance metrics (execution times) are obtained and compared. Experimental results show that, in general, inserts are approximately twice times faster in Microsoft SQL Server because they are injected as plain text without any type of verification, while in PostgreSQL, loaded data includes a validating process, which delays the loading process. Moreover, we did additional indexation tests, from which we concluded that in general, data loading performance degrades. Regarding query performance in PostgreSQL, we conclude that with indexation, queries become three or four percent faster, and six times faster in Microsoft SQL Server.
  • Local e-gov mobile application(s) review
    Publication . Abbasi, Maryam; Cardoso, Filipe; Holanda, Maria; Almeida, Dany; Silva, José; Martins, Pedro
    This study aims to evaluate the adoption of e-government services in Portuguese municipalities, specifically focusing on the usage of mobile applications. Data was collected from 40 of the most populous municipalities in Portugal and analyzed for usage of e-government services such as incidents, traffic conditions, and population alerts through mobile apps. The study found a mixed correlation between population size and e-government app usage, with lower population municipalities showing lower adoption rates. The results suggest that further efforts are needed to improve accessibility and promote e-government services to increase engagement and usage among the local population. The study provides valuable insights for local government representatives and stakeholders to effectively use and access e-government services for the benefit of all residents. The results emphasize the need for effective outreach and promotion strategies, as well as the importance of user testing and feedback in the development process, to ensure that the applications meet the needs and expectations of users. Furthermore, the study highlights the need for investment in marketing and communication initiatives to increase awareness and adoption of e-government apps among the population. In conclusion, this study contributes to the literature on e-government adoption in Portuguese municipalities and provides a foundation for future research in this area. The findings can inform the development of effective policies and strategies to promote the adoption and usage of e-government services, enhance accessibility and efficiency of local government services, and improve the quality of life for residents.
  • Intelligent Electric Vehicle Charging Controller
    Publication . Cardoso, Filipe; Rosado, J.; Silva, Marco; Teixeira, C. J. Coelho; Agreira, C. I. Faustino; Caldeira, Filipe; Baptista, Pedro; Barreto, Francisco; Pereirinha, Paulo G.
    For domestic consumers, electricity tariffs usually have two components: one is related to the maximum available current/total power (billed in C/day) and the other concerns to the energy consumption (C/kWh). The main switchboard current is usually limited, according to the contracted power level, by way of automatic switches. To avoid main switchboard tripping by current limit violation, Electric Vehicle (EV) owners may decide to increase their contracted power (and the energy bill) or to adopt charging strategies that limit the global consumption (EV plus house needs) to the contracted current/power. In this paper, an Intelligent Electric Vehicle Charging Controller (IEVCC), allowing to use the contracted power to the maximum extent, is presented. A set of user configurable parameters can be used to define the controller behavior, in order to prevent a full switch-off. Two versions are described: a single user version that can be used at private houses and a mesh version that can be used in multi apartment buildings, providing information about consumed energy, time of use, costs and past bills.
  • Internet of Things-based care monitoring for the elderly and those with special needs
    Publication . Godinho, António; Cardoso, Filipe; Coelho, Paulo Jorge; Pires, Ivan Miguel
    As a society, we should provide support and care for individuals who are advanced in age or have special needs. We must offer them the opportunity to lead a safe and comfortable life. Sometimes, addressing simple things can mitigate critical problems. For instance, an improperly functioning heating system can put the users’ lives at risk, and a gas leak can prove fatal if not detected in time. Hence, this study aims to identify solutions that can help prevent accidents in such vulnerable populations. To achieve this, a safety device equipped with essential sensors continuously monitors the living environment of people with special needs. If there are any anomalies, the system will immediately alert the concerned family members and competent security authorities, ensuring a quick and efficient response to potential emergencies. The proposed safety device aims to provide extra protection and peace of mind for special care individuals. By implementing such safety measures, we can make significant strides in promoting the well-being and safety of vulnerable populations.
  • An overview on software testing and auditing
    Publication . Lopes, Catia; Cardoso, Filipe; Abbasi, Maryam; Martins, Pedro; Sá, Filipe
    More and more people are dependent on technology. They increasingly use electronic services for day-to-day routines, and user loyalty to the software is essential, being defined by the excellence of the SW. The fewer flaws it has, the greater the likelihood of being able to retain the user’s loyalty. For this situation to be possible, tests are crucial in the development stage since they have the main purpose of identifying errors. To be possible to have a good quality of software, it is important to realize the importance of carrying out tests, as well as to understand what types of tests exist and realize which ones fit in each situation. In addition, the article addresses the life cycle and levels as sociated with software testing. In terms of test automation, there are some tools for developing this type of test, referencing the Katalon stu- diom robot framework, Protractoe and Watir; each is framed in different practical situations.
  • Performance Evaluation Between HarperDB, Mongo DB and PostgreSQL
    Publication . Figueiredo, Figueiredo; Cardoso, Filipe; Saraiva, Goncalo; Rebelo, João; Rodrigues, Ricardo; Wanzeller, Cristina; Martins, Pedro; Abbasi, Maryam
    Several modern-day problems, like information overload and big data, need to deal with large amounts of data. As such, to meet the application requirements, for instance, performance and consistency, more and more systems are adapting to the specificities. The existing Relational Database Management System (RDBMS)’s the processing of massive data has become an issue because these databases do not deal with a massive amount of data. NoSQL is a database management system that makes processing massive and/or unstructured data easier because it uses key-value to store the data, collections or document stores instead of tables. Many companies today tend to start a project using NoSQL. However, HarperDB aims to produce a relational and nonrelational DBMS, allowing developers to choose between different solutions. This paper aims to show the most relevant differences between HarperDB, MongoDB and PostgreSQL and compare their performances. Preliminary results show that PostgreSQL performs better with structured data, but HarperDB can integrate NoSQL and SQL, which can be a significant advantage to HarperDB compared to the other solutions.
  • Comparison of Image Processing and Classification Methods for a Better Diet Decision-Making
    Publication . Abbasi, Maryam; Cardoso, Filipe; Martins, Pedro
    This paper aims to explore the use of different deep learning techniques, specifically convolutional neural networks (CNNs), for dietary assessment through image food recognition and compare their performance to the human visual system (HVS). Currently, there are three main techniques for using CNNs in this task: training a network from scratch; using an off-the-shelf pre-trained network; and performing unsupervised pre-training with supervised adjustments. In this study, the authors evaluate the performance of three CNN models with varying numbers of parameters (5,000 to 160 million) based on dataset size and spatial image context. The authors also consider human knowledge and classification to compare the performance of the CNNs to the HVS. They find that while the CNNs make errors across different food classes, the HVS tends to make semantic errors with specific food classes. As a result, the HVS shows more consistency in its answers. Overall, the findings suggest that the HVS is more accurate when the dataset is diverse, while the CNN performs better when the dataset is focused on a particular niche. In conclusion, this study provides empirical evidence that machine learning can be more efficient than the HVS in certain tasks but also highlights the strengths and limitations of both approaches. The authors suggest that combining CNNs with other classification techniques, such as bagof-words, may be a promising approach for improving the accuracy of dietary assessment through image food recognition.
  • IoT single board computer to replace a home server
    Publication . Godinho, António; Cardoso, Filipe; Rosado, J.; Sá, Filipe
    Home servers are popular among computer enthusiasts for hosting various applications, including Linux OS with web servers, database solutions, and private cloud services, as well as for VPN, torrent, file-sharing, and streaming. Single Board Computers (SBCs), once used for small projects, have now evolved and can be used to control multiple devices in the IoT space. SBCs have become more powerful and can run many of the same applications as traditional home servers. In light of the energy crisis, this study will examine the feasibility of replacing a conventional home server with an SBC while maintaining service quality and evaluating performance and availability. The power consumption of both solutions will be compared.
  • IoT-Based Monitoring System for Photovoltaic Battery Management
    Publication . Sarmento, Gonçalo; Cardoso, Filipe; Mota, Mickael; Henriques, João; Abbasi, Maryam; Martins, Pedro; Wanzeller, Cristina; Caldeira, Filipe
    As number of photovoltaic systems being installed is increasing, also many users are deciding to include batteries, and postpone the consumption of that energy when it is most needed. Moreover,a crucial issue can keep undetected for long time causing dangerous situation which can lead to a potential disaster. However, the chemical nature of batteries makes them unreliable and dangerous. In this risky scenario, it becomes essential to monitor their behaviour in order to avoid accidents. In that purpose, a enabled Internet of Things (IoT) framework is proposed for monitoring the batteries values for temperature and voltage through the use of sensors. If these values becomes abnormal, a notification is triggered to the responsible person. Based on experimental results, the proposed framework to detect and notify hazard situations caused by battery faults.
  • IEVCC - A Mesh Managed Network for Electric Vehicle Charging
    Publication . Baptista, Pedro; Rosado, J.; Silva, Marco; Caldeira, Filipe; Cardoso, Filipe
    The implementation and management of Electric Vehicle (EV) charging points in parking spaces (whether in multifamily condominiums or in private company parking lots) presents a challenge, since the available contracted power may be insufficient for the building devices needs and for EV chargers to work simultaneously. The available power is limited to a fixed value generally determined by the expected peak power consumption of the building. An increase in the contracted power leads to unwanted costs and, sometimes, this is not possible without a complete rework of the electrical installation at even higher costs. The available power is not fully used all the time, since not all the buildings devices are always working simultaneously. These spare power can be monopolized by a mesh network of chargers, taking advantage of the full contracted power without increasing costs. In this work we present a manager of a mesh network of chargers that can distribute the available power to an array of chargers based on several conditions, e.g. load balancing, priority of chargers or charging.