Nuno Fachada

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Verified

Nuno verified their affiliation via an institutional email.

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• PhD Electrical and Computer Engineering
• Professor (Assistant) at Lusophone University of Humanities and Technologies

Agent-based modeling (ABM) is a bottom-up modeling approach, where each entity of the system being modeled is uniquely represented as an independent decision-making agent. Large scale emergent behavior in ABMs is population sensitive. As such, the number of agents in a simulation should be able to reflect the reality of the system being modeled, wh...

Computational models of complex systems are usually elaborate and sensitive to implementation details, characteristics which often affect their verification and validation. Model replication is a possible solution to this issue. It avoids biases associated with the language or toolkit used to develop the original model, not only promoting its verif...

Cellular evolutionary algorithms (cEAs) are a particular type of EAs in which a communication structure is imposed to the population and mating restricted to topographically nearby individuals. In general, these algorithms have longer takeover times than panmictic EAs and previous investigations argue that they are more efficient in escaping local...

In this paper we present a technique for procedurally generating 3D maps using a set of premade meshes which snap together based on designer-specified visual constraints. The proposed approach avoids size and layout limitations, offering the designer control over the look and feel of the generated maps, as well as immediate feedback on a given map’...

Synthetic data is essential for assessing clustering techniques, complementing and extending real data, and allowing for more complete coverage of a given problem’s space. In turn, synthetic data generators have the potential of creating vast amounts of data—a crucial activity when real-world data is at premium—while providing a well-understood gen...

Text clustering is an important method for organising the increasing volume of digital content, aiding in the structuring and discovery of hidden patterns in uncategorised data. The effectiveness of text clustering largely depends on the selection of textual embeddings and clustering algorithms. This study argues that recent advancements in large l...

Adaptive game systems aim to enrich player experiences by dynamically adjusting game content in response to user data. While extensive research has addressed content personalization and player experience modeling, the integration of these components into fully operational adaptive gameplay systems remains limited. This systematic review, conducted...

The Age of Information (AoI) has emerged as a critical performance metric for evaluating time-sensitive wireless communications systems, where maintaining freshness of information and transmission reliability is crucial. In modern ultra-reliable low-latency communication networks, short-packet transmissions are essential for energy efficiency and l...

This paper investigates the performance of 16 Large Language Models (LLMs) in automating LoRaWAN-related engineering tasks involving optimal placement of drones and received power calculation under progressively complex zero-shot, natural language prompts. The primary research question is whether lightweight, locally executed LLMs can generate corr...

This package contains the following files and folders: analysis.ipynb (notebook containing the data analysis presented in the paper, as well as some additional inquiries); data (data generated from the experiences described in the paper, the extracted Python code, and the results for running said code); full_non_agg.xlsx (non-aggregated results ext...

This paper investigates the performance of 16 Large Language Models (LLMs) in automating LoRaWAN-related engineering tasks involving optimal placement of drones and received power calculation under progressively complex zero-shot, natural language prompts. The primary research question is whether lightweight, locally executed LLMs can generate corr...

The increasing frequency and severity of wildfires requires advanced methods for effective surveillance and management. Traditional ground-based observation techniques often struggle to adapt to rapidly changing fire behavior and environmental conditions. This paper examines the application of multispectral aerial and satellite imagery in wildfire...

The field of serious games for health has grown significantly, demonstrating effectiveness in various clinical contexts such as stroke, spinal cord injury, and degenerative neurological diseases. Despite their potential benefits, therapists face barriers to adopting serious games in rehabilitation, including limited training and game literacy, conc...

Text clustering is an important method for organising the increasing volume of digital content, aiding in the structuring and discovery of hidden patterns in uncategorised data. The effectiveness of text clustering largely depends on the selection of textual embeddings and clustering algorithms. This study argues that recent advancements in large l...

The Age of Information (AoI) has emerged as a critical performance metric for evaluating time-sensitive wireless communications systems, where maintaining freshness of information and transmission reliability is crucial. In modern ultra-reliable low-latency communication networks, short-packet transmissions are essential for energy efficiency and l...

Consider a population of size N where each element has an independent probability p of being a success. By sampling this population without replacement, how many elements need to be sampled to find all successes? This paper describes this discrete distribution, derives its main properties, and validates the results through simulation.

We present five project assignments for teaching database concepts to undergraduate students in interdisciplinary degree programs, where teaching databases as a standalone course is not practical. The projects were developed for a CS2-level programming course, where LINQ and basic database concepts are lectured, and have been shown to effectively e...

This paper provides a concise and comprehensive analysis of forest fire spread simulation. The Alexandridis model was implemented and enhanced utilizing stochastic methods in a Python environment. The impact of various factors influencing fire spread was individually studied. Results were empirically analyzed based on model-generated images, addres...

The integration of data science into Geographic Information Systems (GIS) has facilitated the evolution of these tools into complete spatial analysis platforms. The adoption of machine learning and big data techniques has equipped these platforms with the capacity to handle larger amounts of increasingly complex data, transcending the limitations o...

In this study, we present the DP Plugin for IntelliJ IDEA, designed to extend the Drop Project (DP) Automatic Assessment Tool (AAT) by making it more suitable for handling small exercises in exercise-based learning environments. Our aim was to address the limitations of DP in supporting small assignments while retaining its strengths in project-bas...

Patient feedback is a crucial component in identifying areas of improvement and enhancing service quality in healthcare. However, manual analysis of a large volume of reviews is challenging. This paper proposes a novel framework and software for sentiment analysis and topic modeling with the goal of automating this process, providing a more efficie...

The majority of current commercial available Unmanned Aerial Vehicles (UAV) depend mainly on satellite signals to estimate their position. Although this is not a problem in outdoor environments, in scenarios where these signals are obstructed, the UAV may be unable to estimate its position, rendering navigation infeasible. Thus, in satellite-less e...

Modeling and simulation (M&S) serve as essential tools in various scientific and engineering domains, enabling the representation of complex systems and processes without the constraints of physical experimentation. These tools have evolved significantly with the integration of artificial intelligence (AI), which offers advanced capabilities in ess...

This paper presents an initial exploration on the use of 2D cellular automata (CA) for generating 3D terrains through a simple yet effective additive approach. By experimenting with multiple CA transition rules, this preliminary investigation yielded aesthetically interesting landscapes, hinting at the technique's potential applicability for real-t...

Raster Forge is a Python library and graphical user interface for raster data manipulation and analysis. The tool is focused on remote sensing applications, particularly in wildfire management. It allows users to import, visualize, and process raster layers for tasks such as image compositing or topographical analysis. For wildfire management, it g...

Raster Forge is a Python library and graphical user interface for raster data manipulation and analysis. The tool is focused on remote sensing applications, particularly in wildfire management. It allows users to import, visualize, and process raster layers for tasks such as image compositing or topographical analysis. For wildfire management, it g...

The integration of data science into Geographic Information Systems (GIS) has facilitated the evolution of these tools into complete spatial analysis platforms. The adoption of machine learning and big data techniques has equipped these platforms with the capacity to handle larger amounts of increasingly complex data, transcending the limitations o...

This position paper proposes the hypothesis that physiological noise artefacts can be classified based on the type of movements performed by participants in Virtual Reality contexts. To assess this hypothesis, a detailed research plan is proposed to study the influence of movement on the quality of the captured physiological signals. This paper arg...

We present an exploratory study comparing human player performance against online and offline AI learning techniques—the Naive Bayes Classifier and Genetic Algorithms, respectively—using a simple turn-based game. Human player performance is also assessed according to gender, age, experience playing games, and boredom level during game sessions. Hum...

Artificial intelligence (AI) in computer games can enhance the player experience by providing more realistic and dynamic interactions with non-player characters and/or the game environment and is, therefore, an essential skill for game development students to acquire. In this paper, we discuss ten active learning prototypes for undergraduate game d...

Collective organization in multi-party conversations emerges through the exchange of utterances between participants. While most research has focused on content-centred mechanisms that lead to emergent conversational coordination, less attention has been given to explaining conversational order based on who is addressed and who responds, especially...

Contains a CSV file with students replies to the survey used to evaluate the Drop Project Student plugin for IntelliJ IDEA. To support international readers, the question names (CSV headers) were translated to English and/or match the numbering that appear in the paper. However, the student's textual replies to the open ended questions were left i...

This package contains the following files and folders: LICENSE_CODE.txt - The license for the included code. LICENSE_DATA.txt - The license for the included data. README.md - Package description. requirements.txt- Specifies the Python dependencies required for running the included notebook. survey_analysis.ipynb - Notebook used for analyzing the s...

This article presents a dataset of 10,917 news articles with hierarchical news categories collected between 1 January 2019 and 31 December 2019. We manually labeled the articles based on a hierarchical taxonomy with 17 first-level and 109 second-level categories. This dataset can be used to train machine learning models for automatically classifyin...

This article presents a dataset of 10,917 news articles with hierarchical news categories collected between 1 January 2019 and 31 December 2019. We manually labeled the articles based on a hierarchical taxonomy with 17 first-level and 109 second-level categories. This dataset can be used to train machine learning models for automatically classifyin...

Snappable Meshes is an algorithm that procedurally generates 3D environments by iteratively selecting and linking pre-built map pieces. These pieces are triangular meshes annotated by designers with connectors marking potential links, and bounding volumes indicating where overlaps should be avoided. In this article , we present a method for automat...

Technology plays a crucial role in the management of natural resources in agricultural production. Free and open-source software and sensor technology solutions have the potential to promote more sustainable agricultural production. The goal of this rapid review is to find exclusively free and open-source software for precision agriculture, availab...

Supplementary materials for "A Rapid Review on the Use of Free and Open Source Technologies and Software Applied to Precision Agriculture Practices"

Agricultural production needs technologies that assist the management of natural resources, for example, the collection of real-time data on soil, water, weather, crops, and biodiversity conditions. Sensor technology solutions and open-source software are appropriate for promoting more sustainable agricultural production. Among the advantages of us...

Synthetic data is essential for assessing clustering techniques, complementing and extending real data, and allowing for a more complete coverage of a given problem's space. In turn, synthetic data generators have the potential of creating vast amounts of data -- a crucial activity when real-world data is at premium -- while providing a well-unders...

Supplementary materials for the paper "Generating Multidimensional Clusters With Support Lines". Results and images presented in the paper can be reproduced with the Jupyter notebooks included with this Julia project, which contains the following files: `.JuliaFormatter.toml` (formatting rules for the included code), `example.ipynb` (code for the u...

This dataset contains 10,917 news articles with hierarchical news categories collected between January 1st 2019, and December 31st 2019 classified by using NewsCodes Media Topic taxonomy. We manually labelled the articles based on a hierarchical taxonomy with 17 first-level and 109 second-level categories. This dataset can be used to train machine...

We present a targeted curricular improvement on an interdisciplinary Videogames Bachelor of Arts, to be implemented in the 2022/23 academic year. The aim is to solve student adaptation issues with the program's interdisciplinarity that were heightened by the COVID-19 pandemic.

Uavnoma is a set of Python functions and a front-end script for modeling, studying, and analyzing the communication system composed by an unmanned aerial vehicle (UAV) and two ground users. We assume that the UAV acts as an aerial base station to serve the users according to non-orthogonal multiple access (NOMA) principles. For more practical insig...

The Snappable Meshes algorithm procedurally generates 3D maps for computer games by iteratively selecting and linking pre-built map pieces via designer-specified connectors. In this paper we present an implementation of this algorithm in the Unity game engine, describing its architecture and discussing core implementational solutions. A number of e...

Preprocessing text data sets for use in Natural Language Processing tasks is usually a time-consuming and expensive effort. Text data, normally obtained from sources such as, but not limited to, web scraping, scanned documents or PDF files, is typically unstructured and prone to artifacts and other types of noise. The goal of the TextCL package is...

Automated assessment tools (AATs) are software systems used in teaching environments to automate the evaluation of computer programs implemented by students. These tools can be used to stimulate the interest of computer science students in programming courses by providing quick feedback on their work and highlighting their mistakes. Despite the abu...

A retail business is a network of similar-format grocery stores with a sole proprietor and a well-established logistical infrastructure. The retail business is a stable market, with low growth, limited customer revenues, and intense competition. On the system level, the retail industry is a dynamic system that is challenging to represent due to unc...

Wildfires constitute a major socioeconomic burden. While a number of scientific and technological methods have been used for predicting and mitigating wildfires, this is still an open problem. In turn, agent-based modeling is a modeling approach where each entity of the system being modeled is represented as an independent decision-making agent. It...

In this paper we present a technique for procedurally generating 3D maps using a set of premade meshes which snap together based on designer-specified visual constraints. The proposed approach avoids size and layout limitations, offering the designer control over the look and feel of the generated maps, as well as immediate feedback on a given map'...

Skeletal muscle physiology remains of paramount importance in understanding insulin resistance. Due to its high lipid turnover rates, regulation of intramyocellular lipid droplets (LDs) is a key factor. Perilipin 5 (PLIN5) is one of the most critical agents in such regulation, being often referred as a protector against lipotoxicity and consequent...

This dataset contains experts interview results for the Fuzzy Cognitive Map of the retail system, reported influences from the published articles in the domain, and aggregated weighted matrix of influences in the retail system. Based on this dataset Fuzzy Cognitive Map of the retail system was generated. Obtained map used for system analysis and s...

We present SimpAI, an AI agent created for the ColorShapeLinks competition, based on an arbitrarily sized version of the Simplexity board game. The agent uses a highly efficient parallelized Minimax-type search, with an heuristic function composed of several partial heuristics, the balance of which was optimized with an evolutionary algorithm. Simp...

This dataset contains performance and navigation benchmarks obtained by generating eight maps with the snappable meshes algorithm multiple times. A number of results presented in the research paper "Procedural Generation of 3D Maps with Snappable Meshes" are obtained from this dataset. The results presented in the research paper "Procedural Generat...

Resumo não técnico para fins de divulgação científica do artigo "Population sizing of cellular evolutionary algorithms" publicado na revista Swarm and Evolutionary Computation em 2020. Publicado em: Revista Técnica - Associação de Estudantes do Instituto Superior Técnico, 504:53-54

In this paper we introduce PyXYZ, a 3D wireframe software rendering framework for educational purposes. The main goal of this framework is to provide a simple-to-understand tool that students can use to build a more sophisticated engine, while learning mathematics and acquiring a deeper knowledge of the complexity of a modern 3D engine. PyXYZ can b...

ColorShapeLinks is an AI board game competition framework specially designed for students and educators in videogame development, with openness and accessibility in mind. The competition is based on an arbitrarily-sized version of the Simplexity board game, the motto of which, "simple to learn, complex to master", is curiously also applicable to AI...

This dataset contains grades (0-20 scale) given to students in the context of the ColorShapeLinks AI assignment during the two semesters of the 2019/20 academic year. A number of results presented in the research paper "ColorShapeLinks: A Board Game AI Competition for Educators and Students" are obtained from this dataset.

ColorShapeLinks is an AI board game competition framework specially designed for students and educators in videogame development, with openness and accessibility in mind. The competition is based on an arbitrarily-sized version of the Simplexity board game, the motto of which, “simple to learn, complex to master”, is curiously also applicable to AI...

We present a method for procedural generation of 3D levels based on a system of connectors with pins and human-made pieces of geometry. The method avoids size limitations and layout constraints, while offering the level designer a high degree of control over the generated maps. The proposed approach was originally developed for and tested on a mult...

We present a generative swarm art project that creates 3D animations by running a Particle Swarm Optimization algorithm over synthetic landscapes produced by an objective function. Different kinds of functions are explored, including mathematical expressions, Perlin noise-based terrain, and several image-based procedures. A method for displaying th...

Computer games are complex products incorporating software, design and art. Consequently, their development is a multidisciplinary effort, requiring professionals from several fields, who should nonetheless be knowledgeable across disciplines. Due to the variety of skills required, and in order to train these professionals, computer game developmen...

We present an approach for teaching maths to game development undergraduates from a wide variety of backgrounds. We discuss the concepts behind an introductory maths course, its assessment and put forward some preliminary results on a practical implementation .

As unidades curriculares (UCs) de programação num curso de Videojogos devem ter dois objetivos: 1) um objetivo mais geral, que consiste em fornecer aos alunos as bases que lhes permitam assimilar conceitos gerais de programação, matemática e física, bem como desenvolver o seu pensamento lógico e algorítmico; e, 2) um objetivo mais específico, que c...

generateData is a MATLAB/Octave function for generating 2D data clusters. Data is created along straight lines, which can be more or less parallel depending on the selected input parameters. The function also allows to fine-tune the generated data with respect to number of clusters, total data points, average cluster separation and several other di...

This paper investigates the performance and scalability of a new update strategy for the particle swarm optimization (PSO) algorithm. The strategy is inspired by the Bak-Sneppen model of co-evolution between interacting species, which is basically a network of fitness values (representing species) that change over time according to a simple rule: t...

A video game design and development degree is a very specific choice for students, who are mainly interested in making games or taking part in the game development process. Databases are not an apparent requirement in order to pursue these goals, often leading to a lack of motivation and interest in the subject. Nonetheless, a number of Bachelor de...

We investigate the convergence speed, accuracy, robustness and scalability of PSOs structured by regular and random graphs with 3 ≤ k ≤ n. The main conclusion is that regular and random graphs with the same averaged connectivity k may result in significantly different performance, namely when k is low.

This project aims to explore the psychological effect of the player during gaming and how reciprocally game designers can manipulate the sensations of the player through biofeedback information (physiological sensors) and implementation of certain game mechanics. In an initial phase, the objective of the project is to study the physical and psychol...

micompm is a MATLAB / GNU Octave port of the original micompr R package for comparing multivariate samples associated with different groups. Its purpose is to determine if the compared samples are significantly different from a statistical point of view. This method uses principal component analysis to convert multivariate observations into a set o...

The published version of this article should have a dashed line in Table 3 between the 5th and 6th row. The version available in ResearchGate and arXiv is correct.

Verification and validation are two important aspects of model building. Verification and validation compare models with observations and descriptions of the problem modelled, which may include other models that have been verified and validated to some level. However, the use of simulation for modelling social complexity is very diverse. Often, ver...

OpenCL is an open standard for parallel programming of heterogeneous compute devices, such as GPUs, CPUs, DSPs or FPGAs. However, the verbosity of its C host API can hinder application development. In this paper we present cf4ocl, a software library for rapid development of OpenCL programs in pure C. It aims to reduce the verbosity of the OpenCL AP...

The highly multivariate nature of EEG data often limits the search for statistically significant differences in data collected from two or more groups of subjects. We have recently developed a new technique for assessing whether two or more multidimensional samples are drawn from the same distribution. Here, we apply this to EEG data collected from...

Agent-based modeling (ABM) is a bottom-up modeling approach, where each entity of the system being modeled is uniquely represented as a self-determining agent. Large scale emergent behavior in ABMs is population sensitive. As such, it is advisable that the number of agents in a simulation is able to reflect the reality of the system being modeled....

The micompr R package implements a procedure for comparing multivariate samples associated with different factor levels or groups. The procedure uses principal component analysis to convert multivariate observations into a set of linearly uncorrelated statistical measures, which are then compared using a number of statistical methods. This techniqu...

SimOutUtils is a suite of MATLAB/Octave functions for studying and analyzing time series-like output from stochastic simulation models. More specifically, SimOutUtils allows modelers to study and visualize simulation output dynamics, perform distributional analysis of output statistical summaries, as well as compare these summaries in order to asse...

In spatial agent-based models (SABMs) each entity of the system being modeled is uniquely represented as an independent agent. Large scale emergent behavior in SABMs is population sensitive. Thus, the number of agents should reflect the system being modeled, which can be in the order of billions. Models can be decomposed such that each component ca...

OpenCL is an open standard for parallel programming of heterogeneous compute devices, such as GPUs, CPUs, DSPs or FPGAs. However, the verbosity of its C host API can hinder application development. In this paper we present cf4ocl, a software library for rapid development of OpenCL programs in pure C. It aims to reduce the verbosity of the OpenCL AP...

PerfAndPubTools consists of a set of MATLAB/Octave functions for the post-processing and analysis of software performance benchmark data and producing associated publication quality materials.

The R package micompr implements a procedure for assessing if two or more multivariate samples are drawn from the same distribution. The procedure uses principal component analysis to convert multivariate observations into a set of linearly uncorrelated statistical measures, which are then compared using a number of statistical methods. This techni...

SimOutUtils is a suite of MATLAB/Octave functions for studying and analyzing time series-like output from stochastic simulation models. More specifically, SimOutUtils allows modelers to study and visualize simulation output dynamics, perform distributional analysis of output statistical summaries, as well as compare these summaries in order to asse...

Agent-based modeling (ABM) is a bottom-up modeling approach, where each entity of the system being modeled is uniquely represented as an independent decision-making agent. ABMs are very sensitive to implementation details. Thus, it is very easy to inadvertently introduce changes which modify model dynamics. Such problems usually arise due to the la...

Dataset 1. Outputs of 30 replications for all model sizes and parameter set 1. Each text file corresponds to one replication. Columns correspond to outputs in the following order: prey population, predator population, available cell-bound food, mean prey energy, mean predator energy, mean value of the grid cells C state variable. Rows correspond to...

Dataset 2. Outputs of 30 replications for all model sizes and parameter set 2. Each text file corresponds to one replication. Columns correspond to outputs in the following order: prey population, predator population, available cell-bound food, mean prey energy, mean predator energy, mean value of the grid cells C state variable. Rows correspond to...

Each seed was obtained by taking the MD5 checksum of replication number and converting the resulting hexadecimal string to a 32-bit integer (the maximum precision accepted by NetLogo).

Tables S2.1 to S2.10. Statistics and distributional analysis of the selected focal measures for n = 30 replications of the PPHPC model for all the model size and parameter set combinations.

Agent-based modeling (ABM) is a bottom-up modeling approach, where each entity of the system being modeled is uniquely represented as an independent decision-making agent. ABMs are very sensitive to implementation details. Thus, it is very easy to inadvertently introduce changes which modify model dynamics. Such problems usually arise due to the la...

Agent-based modeling (ABM) is a bottom-up modeling approach, where each entity of the system being modeled is uniquely represented as an independent decision-making agent. ABMs are very sensitive to implementation details. Thus, it is very easy to inadvertently introduce changes which modify model dynamics. Such problems usually arise due to the la...

The capacity to predict and control bioprocesses is perhaps one of the most important objectives of biotechnology. Computational simulation is an established methodology for the design and optimization of bioprocesses, where the finite elements method (FEM) is at the state-of-art engineering multi-physics simulation system, with tools such as Finit...