DEI Talks | “Task scheduling algorithms for fog architectures” by Prof. Celestino Lopes de Barros

Celestino Lopes de Barros is Professor at the Faculty of Science and Technology (FCT) of the University of Cape Verde (Uni-CV) since 2005. Graduated in Informatics in 2006 by the Instituto Superior de Educação, he obtained a Master’s degree in Electronic and Engineering and Telecommunications from the University of Aveiro in 2010. Holds the Certificate in Advanced Studies and has a PhD in Science and Technology from UaB and UTAD since 2021. His areas of interest are Cloud computing and its paradigms. Author of several papers focusing on ‘Job Scheduling in Fog Paradigm’.

Join us on the 11th of May, at 14:30, in room I-105 FEUP, for the presentation of “Task scheduling algorithms for fog architectures”


According to the author’s knowledge task scheduling in fog paradigm is highly complex and in the literature there are still few studies on it. In the cloud architecture, it is widely studied and in many researches, it is approached from the perspective of service providers. Trying to bring innovative contributions in these areas, we propose a solution to the context-aware task-scheduling problem for fog paradigm. In our proposal, different context parameters are normalized through Min Max normalization, requisition priorities are defined through the application of the Multiple Linear Regression (MLR) technique and scheduling is performed using Multi-Objective Non-Linear Programming optimization (MONLIP) technique.

7 of the 50 Huawei Scholarships were awarded to L.EIC and M.EIC students

Following the commitment assumed with the education sector in Portugal, through a memorandum of understanding signed during the 2021 edition of the Web Summit, at the StartUp Portugal stand, between Associação DNS.PT (.PT) and Huawei Portugal, Huawei launched a Scholarship Programme directed to university students in the areas of Engineering and Science, having recently recognized 50 university students for their academic and personal merit with the attribution of a scholarship worth 5,000 Euros, in an investment of 250,000 Euros.

For Forbes Portugal, Diogo Madeira da Silva, Head of Public Affairs & Communications at Huawei Portugal said that this is a “significant investment in the training of Portuguese students and an indelible contribution to a more capacitated, more digital and more competitive Portugal”, hence the fact that this initiative is being promoted together with .PT and with the support of INCoDe.2030, of Portugal Digital, the Commission for Citizenship and Equality and the Secretary of State and the Commission for Citizenship and Equality, “guarantees us the alignment with the empowerment, digital transition and equality agenda that the country is pursuing. And we hope that more partners can join this initiative”.

Around 3000 applications were received from young university students from all over the country, including the 7 students from DEI who recently received one of these scholarships that will make all the difference in their academic careers; Sofia Pinto, Tiago Oliveira, Miguel Silva and Diogo Neves are students in the Bachelor in Informatics and Computing Engineering, a joint FEUP/FCUP programme, and Rita Peixoto, Mário Mesquita and Miguel Gomes from the Master in Informatics and Computing Engineering at FEUP.

Talking to Sofia Pinto, she tell us that when she saw the email about the scholarship program, from the L.EIC secretariat, she thought “I think I have the right profile and trying is not difficult” and that’s how she “dared” to participate. And his decision couldn’t have been better, as it will allow her to save to invest in an MBA in the future and to travel, accumulating the experiences provided by what she most likes to do, travel!

Tiago Oliveira, Founder and Associate Director of Easy Future, intends to invest part of the winnings in this association and believes that this project was one of the most valued aspects in his CV, having decisively contributed to his being among the 50 lucky winners. Regarding the future Tiago tells us that he intends to create or work in a company that bets strongly in the technological development of the companies, through low cost means of development of sites and apps and support in the cybersecurity area.

Miguel Silva, 2nd year student at L.EIC, believes that the success of his application was due to his passion for technology, applied to the personal projects he develops in his spare time and also to the work developed in the different student groups where he is inserted. At the same time Miguel already dreams with the ERASMUS program, and counts with the scholarship for the additional costs of a season abroad. “It reassures me to know that I have room to explore different interests and invest in my education from now on”.

 Diogo Neves also sees ERASMUS as one of his academic ambitions because of his lifelong curiosity to get in touch with the digital reality of other countries. Diogo believes that his numerous extra-curricular activities, such as musical projects, social initiatives, involvement in academic associations and the various courses taken outside the area of computing, were the key to getting this grant.

Rita Peixoto considers that it was her professional experience so far, her summer internship, her path at JuniFEUP, namely now as Director of the Technology Department, and also her proactivity, mirrored in the various volunteering activities, the Erasmus+ program of partnership with Secondary Schools, the academic monitoring and the constant presence of sport in her life, the aspects most valued by Huawei.

“My dream is to create my own company and develop an innovative product that will help as many people as possible. Throughout my academic career I try to develop and implement the most different project ideas that I have, and I hope that one day one of them will grow to the point of becoming my job and main focus.” – this is how Miguel Gomes sees his future. As for the present, he considers that his professional experience at INESCTEC and Cloudware, his duties as a monitor at the “consultório digital de matemática” , his involvement in a student group, and the project developed in the IDEIA course unit were decisive for the success of his application.

Mário Mesquita, currently in Hong Kong on an exchange program, believes that his entrepreneurial spirit, applied to activities in student groups, participation in competitions, his professional experience obtained in internships and part-times, and the website he created, were valued and decisive to get this scholarship. He also sees himself as an entrepreneur in the future and does not rule out the possibility of creating his own start-up, but right now he wants to explore the world, although the plan will always be to return and bring the knowledge acquired back to Portugal.

Throughout its 17 years of activity in Portugal, Huawei has deepened a strong connection with Education and talent issues, with this program joining other initiatives and investments in the area, such as Smart Bus, Seeds for the Future, *ICT Academy, Summer School for Female Leadership in Digital Age, or, more recently, the inauguration of 5GAIner, a 5G and Artificial Intelligence lab.

*As part of the partnership established between FEUP and Huawei, which launched in 2020 the ICT Academy program with the aim of providing a comprehensive training solution that covers the development of content in key areas for current challenges and future demands, such as Big Data, Cloud Computing, Artificial Intelligence, Internet of Things or 5G, FEUP students have through this platform the opportunity of free training so that step by step they can start investing in their future.

DEI Talks | Fluent API: A software engineering technique with type theoretical implications by Yossi Gil

Joseph (Yossi) Gil is an Associate Professor at the Faculty of Computer Science of the Technion, Israel Institute of Technology. His publications were in diverse areas including distributed systems, image processing,  algorithms, PRAMs and parallel computing, databases, concepts of object oriented programming, numerical algorithms, … His B.Sc. (in physics summa cum laude), M.Sc. (computer science, summa cum laude) and Ph.D. were awarded by the Hebrew University in Jerusalem. Theoretical computer science, especially lower bounds and algorithms were his academic nursery, but he is also very keen on programming in various programming languages. His current research interest is in type systems and applications of machine learning to software engineering and numerical algorithms.

Join us on the 27th of April, at 14:30, in room B016 FEUP, for the presentation of “Fluent API: A software engineering technique with type theoretical implications”.


 A chain of method calls in an OO language, such as a.b().c(d).e(f,g).h().i()… is what the industry calls fluent API. In such a chain, the return value of all but the last invocation, is the receiver of the next invocation. The technique is advertised and used as a powerful software engineering tool. The technique is also used to embed domain specific languages (DSLs), such as SQL, in a host general programming language, such as Java. In this talk, I will present the technique, and the fundamental theoretical questions: How should one design the classes and methods so that fluent API works the way it is supposed to? What is required from the type system of the host programming language to admit certain chains, and forbid others?

The presentation will survey a series of publications showing deep correspondence between type systems and the theory of automata: finite state automata, pushdown automata, etc.

Mostra da U.Porto is back and from April 21 to 24 can be visited at the Pavilhão Multiusos de Gondomar

The 19th edition of the Mostra da Universidade do Porto runs until April 24 at the Pavilhão Multiusos de Gondomar. With free entrance and transportation, a large number of visitors is expected. They will be welcomed by students, teachers and technicians from various faculties of U.Porto and Research Centers.

Through the dozens of stands, the most curious will be able to experience numerous interactive activities and get to know the training offer of the undergraduate and master’s degree courses.

Students and their families who are considering applying to Higher Education will have the opportunity to attend several information sessions and on Sunday there will be special sessions on the transition from High School to Higher Education and on the social support they can apply for.

This year Mostra brings us a new feature, LIVE sessions that can be watched here.

At the Informatics and Computing Engineering stand, visitors will find motivated students available to answer all questions related to the Bachelor’s and Master’s degrees in Informatics and Computing Engineering and will be challenged to try out some serious games developed in the scope of the curricular units of these courses:

Quantik is a strategic board game. The game logic is developed with SICStus Prolog software and a 3D graphic interface was added later. There are different scenes, lights and cameras that make the environment richer. There are 3 different game modes to choose from: player vs player, player vs bot, and bot vs bot. It is also possible to undo moves and watch the game movie when the game is over.

Cromoparty is a game developed in C and Assembly. It is based on the famous game concept “Dance Dance Revolution”, but with some didactic references to biology, namely the mitosis process. Its main objective was to implement/deal with I/O operations in MinixOS of several devices such as keyboard, mouse, graphics card, etc.

Nudge is a strategic board game for two people. The game logic is developed with SICStus Prolog software and a 3D graphic interface was added later. There are different scenes, lights and cameras that make the environment richer. There are 3 different game modes to choose from: player vs player, player vs AI, and AI vs AI. It is also possible to undo moves and watch the replay when the game is over.

Grace is a telepresence robot that was to host the OpenCx conference at FEUP to be held in 2020, but did not make it due to the Covid 19 pandemic. The robot can be controlled by a Raspberry Pi running on Robot Operative System (ROS). To control the robot remotely, GraceVision was developed, an app on Flutter for iOS and Android that also allows access to the installed camera.

All the information about Mostra and its programme can be found here.

New PhD’s honored in the Conferement Ceremony 2022

The FEUP Auditorium will receive on April 8th, at 17:00, another Conferement Ceremony, which will award the most honorable distinction to those who completed their PhD and defended their thesis in 2020 and 2021.

In the list of honorees we find many students who decided to do their PhDs in DEI Programs. To them our best wishes, professional and personal.


Doctoral Program in Informatics Engineering

Bruno Miguel Carvalhido Lima


Doctoral Program in Digital Media

António Alberto Castro Baía Reis

Daniel dos Santos Catalão

Eduardo José Botelho Batista Morais de Sousa

João Miguel Calisto Marçal

Luciano José Santos Reis Moreira

Roberto Ivo Fernandes Vaz (Cum Laude)


Doctoral Program in Computer Science (Joint program with FCUP, UA and UM)

André Filipe Faria dos Santos

Diogo José Domingues Regateiro

Francisco Nuno Teixeira Neves

João Miguel Maia Soares de Resende

Joaquim Magalhães Esteves da Silva

Jorge Miguel Barros da Silva

José Luís da Silva Devezas (Cum Laude)

Liu Chong

Luís Miguel Tomé Nóbrega

Mariana Rafaela Figueiredo Ferreira de Oliveira

Patrícia Raquel Vieira Sousa

Ricardo Jorge Terroso de Araújo

Ricardo Pereira de Magalhães Cruz

Rogério António da Costa Pontes

Rui Jorge Pereira Gonçalves

Sílvia da Conceição Neto Bessa

DEI Talks | Formal Verification of Distributed Systems by Julien Brunel and David Chemouil

Julien Brunel and David Chemouil are senior researchers at ONERA, in Toulouse, specialized in formal specification and verification. Together with Nuno Macedo and Alcino Cunha (INESC TEC) they designed the 6th version (dubbed Electrum until recently) of the Alloy language and tool (originally proposed by the MIT). In recent years, Julien Brunel and David Chemouil have also been studying the verification of distributed algorithms. A recent highlight is the first mechanical proof of correctness of the distributed maintenance algorithm of the Chord peer-to-peer protocol, as well as formal techniques for the complete, semi-automatic verification of infinite-state systems, such as distributed algorithms.

Join us on the 8th April, at 14:30, in room I-105 of FEUP, for the presentation of this work.


The verification of distributed systems is challenging because these systems combine a rich structure, a high number of elements and a non-trivial temporal evolution. A trade-off between automation and completeness of the verification has to be made. In particular, one can use theorem provers, which offer complete confidence but tend to require considerable expertise and effort. Another option is to use model checkers, which offer complete automation, but cannot handle complex data structures and configurations.

In this talk, they will present recent work on verification techniques for distributed systems that are automatic and “as complete as possible”, or complete and “as automatic as possible”. They will illustrate their work with the analysis of Chord, a scalable distributed hash table.

INFORMATICS.OnBoard, the Informatics Engineering * Interpares Mentoring Program, promoted last April 2nd another social event between L.EIC 1st year students and their mentors.

The group went out to discover the “Little Portuguese Tibet” through the Brandas de Sistelo Trail (PR14 Walk). In this scenery of true rural beauty, where the fabulous terraces stand out in the landscape, students and teachers were able to socialize informally, in collaborative dynamics that promote mutual help, integration, friendship and well-being.

This was the second activity of the 2021/2022 edition. All the others can be seen at Informatics On Board

* Interpares Mentoring Program

 The Faculty of Engineering of the University of Porto has an INTERPARES MENTORING program in operation, aimed at students entering for the first time in this institution of Higher Education (mentees), both national and international, with the objective of supporting them in this new phase of their academic path. This program of social and academic integration is carried out by students (mentors) already attending the different courses in more advanced years, and coordinated by a team of teachers, being adapted to each course according to its characteristics. This program is totally voluntary for both mentors and mentees. This initiative is currently integrated in the U. Porto Mentoring Program.

DEI Talks | JUMPING FINITE AUTOMATA by Prof. Alexander Meduna

Prof. Alexander Meduna (born 1957 in Olomouc, Czech Republic ) is a theoretical computer scientist and expert on compiler design, formal languages and automata. He is a professor of Computer Science at the Brno University of Technology. Formerly, he taught theoretical computer science at various European and American universities, including the University of Missouri, where he spent a decade teaching advanced topics of formal language theory. He wrote over ninety papers related to theoretical computer science.

Join us on the 7th April, at 14:30, in room I-105 of FEUP, for the presentation of JUMPING FINITE AUTOMATA


This talk proposes a new investigation area in automata theory — jumping finite automata. These automata work like classical finite automata except that they read input words discontinuously — that is, after reading a symbol, they can jump over some symbols within the words and continue their computation from there. The talk gives several results concerning jumping finite automata in terms of commonly investigated areas of automata theory, such as closure properties. Most importantly, it achieves several results that demonstrate differences between jumping finite automata and classical finite automata. In its conclusion, the talk  formulates several open problems and suggests future investigation areas.

His latest book is Handbook of Mathematical Models for Languages and Computation

Meduna, Alexander; Tomko, Martin, Horacek, Petr (2019)

The Institution of Engineering and Technology, Stevenage, UK, ISBN: 978-1-78561-660-0

His previous books include

  • Meduna, Alexander (2000). Automata and Languages: Theory and Applications. Springer Science & Business Media. ISBN 9781852330743.
  • Meduna, Alexander (2007). Elements of Compiler Design. CRC Press. ISBN 9781420063233.
  • Meduna, Alexander (2014). Formal Languages and Computation: Models and Their Applications. CRC Press. ISBN 9781466513457.
  • Meduna, Alexander; Švec, Martin (2005). Grammars with Context Conditions and Their Applications. John Wiley & Sons. ISBN 9780471736554.
  • Meduna, Alexander; Techet, Jiří (2010). Scattered Context Grammars and Their Applications. WIT Press. ISBN 9781845644260.
  • Meduna, Alexander; Zemek, Petr (2014). Regulated Grammars and Automata. Springer. ISBN 9781493903696.
  • Meduna, Alexander; Soukup, Ondřej (2017). Modern Language Models and Computation: Theory with Applications. Springer. ISBN 9783319630991.

PhD Defense in Informatics Engineering: ”Increasing the Dependability of Internet-of-Things Systems in the context of End-User Development Environments”

João Pedro Matos Teixeira Dias

Date, Time e Place
1st of April, 09:00, remotely with streaming at:

President of the Jury
PhD Rui Filipe Lima Maranhão de Abreu, Full Professor at Faculdade de Engenharia da Universidade do Porto

PhD Dariusz Mrozek, Associate Professor at the Department of Applied Informatics at Silesian University of Technology, Poland;
PhD Pedro Nicolau Faria da Fonseca, Assistant Professor at the Department of Electronics, Telecommunications and Informatics of Universidade de Aveiro;
PhD André Monteiro de Oliveira Restivo, Assistant Professor at the Department of Informatics Engineering of Universidade do Porto;
PhD Hugo José Sereno Lopes Ferreira, Assistant Professor at the Department of Informatics Engineering of Universidade do Porto (Supervisor).


The ubiquitousness of computing, known as Internet-of-Things (IoT), has reshaped the way people interact with the physical world. However, the scale, distribution — both logical and geographical –, density, heterogeneity, interdependence, and {quality-of-service} requirements of these systems make them complex, posing several challenges from both operational and development viewpoints.

While there is a consensus that the widely used software engineering practices are inadequate for IoT development, they remain the go-to solutions for most practitioners. This aspect has severely compromised their dependability, centralizing most of the computation of these (soft) real-time systems in cloud infrastructure. Likewise, as these systems scale in terms of devices and applications, it outreaches existing technical resources to manage and operate them, becoming of paramount importance, making them as most self-managed as possible while empowering the ability of system operators (including end-users) to configure and understand them — mainly using solutions that do not require high technical expertise, viz. low-code development solutions — including the configuration of fail-safe measures.

This dissertation’s primary focus is to research how to improve the current status quo on the dependability of IoT. However, this is a manifold endeavor: (1) what are the best practices for developing IoT dependably, and what is their scientific soundness, (2) do the current solutions give the fundamental building blocks that allow to design and construct dependable systems, and, if not, what contributions are needed to overcome the existing limitations, and, lastly, (3) giving that these systems are operated by humans with limited technical expertise, it is required that their users can use and configure them without compromising their correct operation. As we set ourselves to tackle these challenges, we claim that:

It is possible to enrich IoT-focused end-user development environments in such a way that the resulting systems have a higher dependability degree, with the lowest impact on the know-how of the (end-)users.

As preliminary research, to understand what end-users want to automate and how they wish to perform such automations, a study was carried to collect automation scenarios. These scenarios showcased the complexity of the automations that some end-users want to perform and the interdependencies between different information sources, devices, and persons. It also supported the view that some of the appliances that end-users want to automate can have nefarious effects if a malfunction happens or a misconfiguration is performed.

We followed extensive literature research and experimental process to mine a set of patterns that can be used to improve IoT systems by making them more dependable, documenting them as patlets, which summarily describe solutions that address some particular problem within a specific context. We further studied a subset of these patterns as a self-healing pattern language that contemplates the use of more than one pattern in tandem to address systems’ operational concerns autonomically.

Adopting these patterns depends on supporting foundations, which include architectural and functional aspects of the target systems. A key aspect is that most of the current solutions do not provide any features to readjust their intrinsic behaviors during runtime — with the software that runs on edge devices being mostly set on stone, delegating all the computational needs to cloud-based services. The research on fog and edge computing attempt to mitigate this by leveraging computational resources across architectural tiers, making the resulting systems more dependable and improving their scalability. Taking on these foundations, we explored and asserted the feasibility of using serverless functions in the IoT context, optimizing the choice of execution contexts according to a priori preferences, constraints, and latencies.

To understand how these paradigms can be leveraged in widely used solutions, we select the open-source Node-RED solution as the experimental base, given its popularity. It provides a visual programming interface that increases its target user base across different expertise levels. Like other available solutions, Node-RED does not provide any feature that allows it to orchestrate tasks across devices or deal with system parts’ failures, limiting the dependability of systems built with it. Nonetheless, given its open-source and extensible nature, we proceed to address some of its limitations. We proceed to evaluate empirically, both in virtual and physical setups, the feasibility of using Node-RED as an orchestrator, where computational tasks are allocated to the available resources, and failures are mitigated by re-orchestrating as devices fail and recover. We also implemented a set of extensions for Node-RED that allows one to enrich the existing programs (i.e., flows) with self-healing capabilities — allowing the detection errors of different parts during runtime, and readjust its behavior to keep delivering correct service by recovering to normal operation, or, at least, maintain its operation within acceptable Quality-of-Service levels.

As IoT users have different expertise levels, we also attempt to improve the interaction with these systems in a way that the users can understand what the configured automations are (viz. inspection), how it is behaving (viz. observability and feedback), and increase their capability to know what was the possible cause behind certain events (viz. causality). In the first study, we extended the visual notations and functionalities of Node-RED to improve the development process using it. We proceed to empirically evaluate the performance of our solution against a non-modified version of Node-RED, observing statistically significant improvements in the users’ ability to evolve existing IoT deploys. Lastly, we explored the use of voice assistants as an alternative way of configuring, understanding, and interacting with IoT-enriched environments, with a particular focus on the ability of a user to understand the cause behind some events. We assert the feasibility of our solution by covering all the different automation possibilities that Node-RED supports, with a considerable extension of the interaction possibilities due to multi-message dialogs support. We proceeded to empirically validate the feasibility of users using the voice assistant to complete different tasks, and all the users were able to finish the tasks. While some valid sentences were incorrectly recognized, forcing the user to repeat their intent, participants expressed a preference for voice interfaces over visual ones in terms of subjective perception.

These contributions materialize into a core set of building blocks that, in assemble, can be used to improve the dependability of IoT systems while leveraging abstractions that do not hinder the (end-)user capability to configure, use, and evolve them. The experimental counterparts of the contributions provide empirical supporting evidence for the plausibility of the hypothesis.

Talk | “Interactive Music Analysis using the DFT and Pitch-Class Distributions extracted from MIDI files” by Fabian C. Moss

Fabien C. Moss is a Research Fellow in Cultural Analytics at University of Amsterdam (UvA). Working with large symbolic datasets of musical scores and harmonic annotations, he is primarily interested in Computational Music Analysis, Music Theory, Music Cognition, and their mutual relationship. His research is inherently interdisciplinary and aims to bridge the humanities and the sciences by drawing on methods and concepts from the Musicology and Music Theory, Mathematics, Music Information Retrieval, Data Science and Machine Learning, Music Psychology and Cognition, and the Digital Humanities.

Join us on the 4th of April, at 14:30, in room B015 of FEUP, for the presentation of “Interactive Music Analysis using the DFT and Pitch-Class Distributions extracted from MIDI files

By the author:

“The discrete Fourier transform (DFT) is a cornerstone of digital signal processing and commonly used to extract periodicities in time-continuous signals.

In recent years, however, mathematical music theorists have begun to explore DFT’s potential when applied not to the time but to the pitch-class domain, where the periodicities are given by equal divisions of the octave [1-3]. Earlier this year, we introduced wavescapes [4], a visualization method of hierarchical pitch-class relations in pieces of music.

Building on this work, we are currently developing midiVERTO [5], an interactive web app to analyze MIDI files using the DFT, that allows users to create wavescapes and inspect the dynamics of pitch-class distributions at several hierarchical levels. In my presentation, I will briefly introduce the underlying theoretical work followed by a tutorial on how to use the app for music analysis.

[1] Amiot (2016). Music Through Fourier Space: Discrete Fourier Transform in Music Theory. Springer.

[2] Noll (2019). Insiders’ Choice: Studying Pitch Class Sets Through Their Discrete Fourier Transformations. InMathematics and Computation in Music (pp. 371–378). Springer.

[3] Tymoczko & Yust (2019). Fourier Phase and Pitch-Class Sum. In Mathematics and Computation in Music (pp. 46–58). Springer.

[4] Viaccoz, C., Harasim, D., Moss, F. C., & Rohrmeier, M. (2022). Wavescapes: A visual hierarchical analysis of tonality using the discrete Fourier transform. Musicae Scientiae

[5] Harasim, D., Affatato, G., & Moss, F. C. (2022). midiVERTO: A Web Application to Visualize Tonality in Real Time. arXiv:2203.13158 [cs]