Filipe Alexandre Sá

Instituto Politécnico de Coimbra | IPC · Departamento de Engenharia Informática e de Sistemas

Modern web development methods use full-stack to split front-end (client-side) and back-end (server-side) components. Front-end technologies involve what the user sees and interacts with, and back-end technologies involve the server-side logic, databases, and server configuration. Both sections can be technologically independent, yet there’s a need...

Application Programming Interfaces (APIs) are available in virtually every programming language. These interfaces make it easier to develop software by simplifying complex code into a more straightforward, manageable structure. APIs provide a standardized interface that allows different applications to communicate and connect easily, streamlining t...

At the beginning of 2020, the major browser-developing companies announced that newer software versions no more extended support for older TLS, 1.0 and 1.1. A warning message was displayed in older versions; the user could override it and enter the website. After implementing the deprecation of TLS 1.0 and TLS 1.1, the users can no longer enter tho...

Application Programming Interfaces (APIs) are available in virtually every programming language. These interfaces make it easier to develop software by simplifying complex code into a more straightforward, manageable structure. APIs provide a standardized interface that allows different applications to communicate and connect easily, streamlining t...

At the beginning of 2020, the major browser-developing companies announced that newer software versions no more extended support for older TLS, 1.0 and 1.1. A warning message was displayed in older versions; the user could override it and enter the website. After implementing the deprecation of TLS 1.0 and TLS 1.1, the users can no longer enter tho...

Data growth is exponential and nearly immeasurable. We used to talk about megabytes when we spoke about data, but now we talk about petabytes with BigData. This data growth makes sensitive data and identifiers increasingly exposed. To address this issue, there is anonymization data, which attempts to “mask” the data so that it is nearly difficult t...

Mobile devices and their applications have become integral in our daily lives, with people spending an average of 3 hours and 15 minutes on their phones each day. The growth in mobile applications has increased the number of interfaces that users interact with, making usability and user satisfaction crucial for their success. This paper aims to com...

This paper presents a novel architecture for enhancing the banking experience by combining microservices and a mobile application. The use of microservices provides scalability and flexibility in the development process, making it easier to add new features or modify existing ones. The results of the study shows that the proposed architecture is ca...

With the popularity of smartphones and mobile devices, mobile application (a.k.a. "app") markets have been growing exponentially in terms of the number of users and downloads. To increase user satisfaction, app developers invest a lot of work into gathering and utilizing user input. This paper presents an analysis of the mobile app market through t...

Waste collection is a traditional process that involves a driver collecting waste from a set of designated deposits based on a predetermined route. The authors present a new approach that utilizes Artificial Intelligence to define the route based on the occupancy volume of the deposits. The new process involves the use of a mobile application to as...

The number of mobile devices operating worldwide has reached almost 15 billion, and Android has become the most popular operating system. Consequently, massive amounts of user data need to be collected and processed, and mobile applications now have essential roles in knowledge management. Dealing with such an amount of data on a single mobile devi...

NoSQL databases were created with the primary goal of addressing the shortcomings in the efficiency of relational databases, and can be of four types: document, column, key-value, and graph databases. Graph databases can store data and relationships efficiently, and have a flexible and easy-to-understand data schema. In this paper, we perform an ex...

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...

NoSQL document databases emerged as an alternative to relational databases for managing large volumes of data. NoSQL document databases ensure big data storage and good query performance and are essential when the data scheme does not fit into the scheme of relational databases. They store their data in the form of documents and can handle unstruct...

Over time, data growth across technology platforms has become a challenge for relational databases. Therefore, it becomes difficult to store and process massive volumes of data and data where the schema is represented by graphs, such as social networking sites. Graph databases emerged as the solution, wherein entities from the domain of interest ar...

A Distributed Denial-of-Service attack uses multiple sources operating in concert to attack a network or site. A typical DDoS flood attack on a website targets a web server with multiple valid requests, exhausting the server's resources. The participants in this attack are usually com-promised/infected computers controlled by the attackers. There a...

Background: Relational databases have been a prevalent technology for decades, using SQL (Structured Query Language) to manage data. However, the emergence of new technologies, such as the web and the cloud, has brought the requirement to handle more complex data. NewSQL is the latest technology that incorporates the ability to scale and ensures th...

Analyze and understand how to combine data warehouse with business intelligence tools, and other useful information or tools to visualize KPIs are critical factors in achieving the goal of raising competencies and business results of an organization The main objective of this paper is to present the development of a BI platform, using DW tools to c...

Due to the SARS-COV-2 pandemic, educational institutions are immediately faced with a new challenge to adapt, forcing the transition from face-to-face teaching to distance learning in a short period. Distance education supported by technology is a challenge for educational institutions based on binomial technology/teaching. This paper presents a pr...

Due to the SARS-COV-2 pandemic, educational institutions are immediately faced with a new challenge to adapt, forcing the transition from face-to-face teaching to distance learning in a short period. Distance education supported by technology is a challenge for educational institutions based on binomial technology/teaching. This article presents a...

As the amount of information flow increases, business companies feel the need to improve on storage systems. Henceforth, to tackle this increasing need, paradigms such as NoSQL emerge to solve the unlimited data growing requirement. However, the NoSQL solution has no proofs given in the field to support their solution claims.

More and more people are dependent on technology. They increasingly use electronic services for day-today 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 cruc...

The selected database engine significantly impacts the performance of electronic services. This impact also affects governmental e-services. Based on several inquiries to all Portugal city halls, this study ranks the different available databases (commercial and non-commercial) in the year 2019.

With the rapid increase of cloud computing, big data and real time web applications, there is eminent need for databases that can handle and process large volumes of data, with high-performance and great scaling capabilities. Since its beginning this was the main goal for NoSQL databases. In this paper we will touch bases with three of the most pop...

This article aims to introduce the concept of NoSQL, describe the database systems Cassandra and MongoDB, but above all, perform a comparative study (practical) of both systems, on the same dataset. The YCSB benchmark tool is to test different types of operations - reading, writing, and reading and writing - by performing these tests on various wor...

Relational databases are getting bigger and more complex. Also, current Database Management Systems (DBMSs) need to respond efficiently to operations on their data. In this context, database optimization is evident as a process of refining database systems, aiming to improve their throughput and performance. This paper evaluates and compares the pe...

In this paper, we investigate the problem of providing scalability (out and in) to Extraction, Transformation, Load (ETL) and Querying (Q) (ETL+Q) process of data warehouses. In general, data loading, transformation, and integration are heavy tasks that are performed only periodically, instead of row by row. Parallel architectures and mechanisms ca...

The complex way radio waves propagate indoors, leads to the derivation of location using fingerprinting techniques. In this cases, location is computed relying on WiFi signals strength mapping. Recent Bluetooth low energy (BLE) provides new opportunities to explore positioning. In this work is studied how BLE beacons radio signals can be used for i...

Analyze and understand how to combine data warehouse with business intelligence tools, and other useful information or tools to visualize KPIs are critical factors in achieving the goal of raising competencies and business results of an organization. This article reviews data warehouse concepts and their appropriate use in business intelligence pro...

Large amounts of data (BigData) are nowadays stored using NoSQL databases and typically stored and accessed using a key-value format. However, depending on the NoSQL database type, different performance is offered. Thus, in this paper, NoSQL database performance is evaluated and compared in aspects relating with, query performance, based on reads a...

Fast population growth in cities and surrounding regions force cities to become smarter to have a sustainable economy, social quality, and environmental well-being. Smart-Cities will be the ones using information and communication technologies to make cities services more efficient (in performance and cost), interactive, and aware of events. For a...

The implementation of Smart-Cities is growing all over the world. From big cities to small villages, information able to provide a better and efficient urban management is collected from multiple sources (sensors). Such information has to be stored, queried, analyzed and displayed, aiming to contribute to a better quality of life for citizens and a...

The complex way radio waves propagate indoors, leads to the derivation of location using fingerprinting techniques. In this cases, location is computed relying on WiFi signals strength mapping. Recent Bluetooth Low Energy (BLE) provides new opportunities to explore positioning. Indoor location identification plays a fundamental role as a business a...

E-services provided by local governments should offer quality services with a great degree of proximity to people and companies. These services must be provided with the highest level of quality, and proper tools must be developed with a view to this end. In this sense, this paper sets forth the results obtained after applying a first round of the...

Com este trabalho de doutoramento, pretendemos desenvolver um modelo abrangente para a avaliação da qualidade do governo local online. Face à crescente evolução tecnológica e ao acesso diário aos serviços públicos, por parte da população, governos por todo o mundo são confrontados com o constante desafio de transformação e reinvenção, a fim de pre...

This paper sets forth the results obtained after applying a first round of the Delphi Method process towards the development of an evaluation model for the quality of local government online services. In this first round, we submitted a list of thirty quality dimensions divided amongst four domains to a group of fifty local e-government experts. Th...

The study presented in this article will serve as a basis for the development of a suitable model whose purpose is to evaluate the quality of local e-Government online services. Citizens expect quality public services, and their online dimension is no exception. The quality of these services should be analysed and accounted for, in order to maximiz...

The study presented in this article will serve as a basis for the development of a suitable methodology whose purpose is to evaluate the quality of Local e-Government services. Citizens expect quality public services, and their online dimension is no exception. The quality of these services should be analysed and accounted for, in order to maximize...

Resumo: O estudo apresentado neste artigo servirá de base à elaboração de uma metodologia que se adeque e permita avaliar a qualidade dos serviços de governo eletrónico local. Os cidadãos esperam que os serviços públicos tenham qualidade e a sua vertente online não é exceção. A qualidade destes serviços deve ser analisada e tomada em conta, para as...

The study presented in this chapter will serve as a basis for the development of a suitable methodology whose purpose is to evaluate the quality of Local e-Government online services. Citizens expect quality public services, and their online dimension is no exception. The quality of these services should be analysed and accounted for, in order to m...

The study presented in this article will serve as a basis for the development of a suitable methodology whose purpose is to evaluate the quality of Local e-Government online services. Citizens expect quality public services, and their online dimension is no exception. The quality of these services should be analysed and accounted for, in order to m...

An Information Architecture is the basis for a comprehensive and integrated information system of any organization, capable of providing answers that meet the challenges posed by the contemporary competitive environment. In this paper we analyse a number of representative methodologies used in Information Architecture definitions and, based on a se...

An Information Architecture is the basis for a comprehensive and integrated information system of any organization, capable of providing answers that meet the challenges posed by the contemporary competitive environment. In this paper we identify representative methodologies used in Information Architecture definitions, and we present an Informatio...

Resumo: Uma arquitetura de informação é a base para as organizações disporem de um sistema de informação abrangente e integrado, capaz de proporcionar uma resposta alinhada com as exigências do ambiente competitivo atual. Neste artigo são identificadas metodologias representativas para a definição de arquiteturas de informação e é apresentado um es...