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Publications

Publications by CRAS

2024

Balancing Plug-In for Stream-Based Classification

Authors
de Arriba-Pérez, F; García-Méndez, S; Leal, F; Malheiro, B; Burguillo-Rial, JC;

Publication
INFORMATION SYSTEMS AND TECHNOLOGIES, VOL 1, WORLDCIST 2023

Abstract
The latest technological advances drive the emergence of countless real-time data streams fed by users, sensors, and devices. These data sources can be mined with the help of predictive and classification techniques to support decision-making in fields like e-commerce, industry or health. In particular, stream-based classification is widely used to categorise incoming samples on the fly. However, the distribution of samples per class is often imbalanced, affecting the performance and fairness of machine learning models. To overcome this drawback, this paper proposes Bplug, a balancing plug-in for stream-based classification, to minimise the bias introduced by data imbalance. First, the plugin determines the class imbalance degree and then synthesises data statistically through non-parametric kernel density estimation. The experiments, performed with real data from Wikivoyage and Metro of Porto, show that Bplug maintains inter-feature correlation and improves classification accuracy. Moreover, it works both online and offline.

2024

Citizen Engagement in Urban Planning - An EPS@ISEP 2022 Project

Authors
Cardani, CG; Couzyn, C; Degouilles, E; Benner, JM; Engst, JA; Duarte, AJ; Malheiro, B; Ribeiro, C; Justo, J; Silva, MF; Ferreira, P; Guedes, P;

Publication
INFORMATION SYSTEMS AND TECHNOLOGIES, VOL 2, WORLDCIST 2023

Abstract
Involving people in urban planning offers many benefits, but current methods are failing to get a large number of citizens to participate. People have a high participation barrier when it comes to public participation in urban planning - as it requires a lot of time and initiative, only a small non-diverse group of citizens take part in governmental initiatives. In this paper, a product is developed to make it as easy as possible for citizens to get involved in construction projects in their community at an early stage. As a solution, a public screen is proposed, which offers citizens the opportunity to receive information, view 3D models, vote and comment at the site of the construction project via smartphone - the solution was named Parcitypate. To explain the functions of the product, a prototype was created and tested. In addition, concepts for branding, marketing, ethics, and sustainability are presented.

2024

Programmer User Studies: Supporting Tools & Features

Authors
Costa, L; Barbosa, S; Cunha, J;

Publication
2024 IEEE SYMPOSIUM ON VISUAL LANGUAGES AND HUMAN-CENTRIC COMPUTING, VL/HCC 2024

Abstract
User studies are paramount for advancing science. In particular, the empirical evaluation of programmer-oriented tools is important to validate research ideas and prototypes, as well as production-ready tools. Previous research has collected several tools used by the software engineering and behavioral science communities to design and run studies. In this work, we study tools used in software engineering studies and identify their features. Furthermore, we analyze three behavioral science experiment tools to identify design ideas that might be adapted to programmer user studies. With this work, we present the set of features currently offered by software engineering tools to support researchers in the design and execution of programmer user studies. We also present the characteristics of some tools used in behavioral science experiments to identify design ideas that can be adapted to programmer user studies.

2024

Characterisation of Dansgaard-Oeschger events in palaeoclimate time series using the matrix profile method

Authors
Barbosa, S; Silva, ME; Rousseau, DD;

Publication
NONLINEAR PROCESSES IN GEOPHYSICS

Abstract
Palaeoclimate time series, reflecting the state of Earth's climate in the distant past, occasionally display very large and rapid shifts showing abrupt climate variability. The identification and characterisation of these abrupt transitions in palaeoclimate records is of particular interest as this allows for understanding of millennial climate variability and the identification of potential tipping points in the context of current climate change. Methods that are able to characterise these events in an objective and automatic way, in a single time series, or across two proxy records are therefore of particular interest. In our study the matrix profile approach is used to describe Dansgaard-Oeschger (DO) events, abrupt warmings detected in the Greenland ice core, and Northern Hemisphere marine and continental records. The results indicate that canonical events DO-19 and DO-20, occurring at around 72 and 76 ka, are the most similar events over the past 110 000 years. These transitions are characterised by matching transitions corresponding to events DO-1, DO-8, and DO-12. They are abrupt, resulting in a rapid shift to warmer conditions, followed by a gradual return to cold conditions. The joint analysis of the delta 18O and Ca2+ time series indicates that the transition corresponding to the DO-19 event is the most similar event across the two time series.

2024

SHORT: Evaluating Tools for Enhancing Reproducibility in Computational Scientific Experiments

Authors
Costa, L; Barbosa, S; Cunha, J;

Publication
PROCEEDINGS OF THE 2ND ACM CONFERENCE ON REPRODUCIBILITY AND REPLICABILITY, ACM REP 2024

Abstract
Ensuring the reproducibility of computational scientific experiments is crucial for advancing research and fostering scientific integrity. However, achieving reproducibility poses significant challenges, particularly in the absence of appropriate software tools to help. This paper addresses this issue by comparing existing tools designed to assist researchers across various fields in achieving reproducibility in their work. We were able to successfully run eight tools and execute them to reproduce three existing experiments from different domains. Our findings show the critical role of technical choices in shaping the capabilities of these tools for reproducibility efforts. By evaluating these tools for replicating experiments, we contribute insights into the current landscape of reproducibility support in scientific research. Our analysis offers guidance for researchers seeking appropriate tools to enhance the reproducibility of their experiments, highlighting the importance of informed technical decisions in facilitating reproducibility across diverse domains.

2024

Mapping the Deepest Natural Underwater Cave

Authors
Soares, E; Almeida, C; Matias, B; Pereira, R; Sytnyk, D; Silva, P; Pereira, T; Lima, P; Martins, A; Almeida, J;

Publication
OCEANS 2024 - SINGAPORE

Abstract
The Czech Republic is home to the Hranice Abyss, the world's deepest natural underwater cave, a site extensively explored by a dedicated team of divers from a speleology group. Over the years, numerous studies have been conducted to unravel the cave's mysteries, delving into fields such as biology, hydrogeology, and geology. Mapping a cave of such vast dimensions and staggering depth poses formidable challenges, making the task hazardous, demanding, and timeintensive for a limited team of divers. In July 2022, the UNEXUP project was invited to explore and map the cave with its robot (UX1-neo), which contains many acoustic and optical sensors, used for navigation, localization, and mapping. Its unique control and dynamics allow the robot to successfully navigate through caves and flooded mines. This paper delves into the specifics of the six days of mission dives, offering insights into the mapping process, and presenting some of the results obtained from the entire cave.

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