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Publications

Publications by HASLab

2022

A data mining approach to classify serum creatinine values in patients undergoing continuous ambulatory peritoneal dialysis

Authors
Brito, C; Esteves, M; Peixoto, H; Abelha, A; Machado, J;

Publication
WIRELESS NETWORKS

Abstract
Continuous ambulatory peritoneal dialysis (CAPD) is a treatment used by patients in the end-stage of chronic kidney diseases. Those patients need to be monitored using blood tests and those tests can present some patterns or correlations. It could be meaningful to apply data mining (DM) to the data collected from those tests. To discover patterns from meaningless data, it becomes crucial to use DM techniques. DM is an emerging field that is currently being used in machine learning to train machines to later aid health professionals in their decision-making process. The classification process can found patterns useful to understand the patients' health development and to medically act according to such results. Thus, this study focuses on testing a set of DM algorithms that may help in classifying the values of serum creatinine in patients undergoing CAPD procedures. Therefore, it is intended to classify the values of serum creatinine according to assigned quartiles. The better results obtained were highly satisfactory, reaching accuracy rate values of approximately 95%, and low relative absolute error values.

2022

DESIGN AND IMPLEMENTATION OF A CHATBOT AS A TOOL TO ASSIST A HELPDESK TEAM

Authors
Ribeiro, DP; Anjo, A; Henriques, PR;

Publication
International Conference on Applied Computing 2022 and WWW/Internet 2022

Abstract
The existence of internal helpdesk teams is a common occurrence in companies nowadays, especially when considering the IT sector. These teams are an expensive resource and are only able to serve a limited number of users at a given moment, which evidences the importance of helpdesk teams operating as efficiently as possible. A common occurrence in the daily operations of these teams consists in the existence of a set of repeated tasks that could be automated through the usage of a chatbot capable of acting on behalf of helpdesk team members. By allowing a chatbot to perform some of these repeated actions, helpdesk teams are able to focus on other tasks, thus allowing to increase their productivity. Additionally, the usage of chatbots to assist a helpdesk team creates a highly available tool, capable of giving answers in a short time frame. In this paper, the design and implementation of such a tool is presented, including concepts and approaches related to chatbot development. As a result, a fully functional chatbot named Triton was produced, capable of helping employees of a consulting company with helpdesk-related problems and questions. Copyright © (2022) by International Association for Development of the Information Society (IADIS). All rights reserved.

2022

An Evaluation of Graph Databases and Object-Graph Mappers in CIDOC CRM-Compliant Digital Archives

Authors
Costa, L; Freitas, N; da Silva, JR;

Publication
ACM JOURNAL ON COMPUTING AND CULTURAL HERITAGE

Abstract
The Portuguese General Directorate for Book, Archives and Libraries (DGLAB) has selected CIDOC CRM as the basis for its next-generation digital archive management software. Given the ontological foundations of the Conceptual Reference Model (CRM), a graph database or a triplestore was seen as the best candidate to represent a CRM-based data model for the new software. We thus decided to compare several of these databases, based on their maturity, features, performance in standard tasks and, most importantly, the Object-Graph Mappers (OGM) available to interact with each database in an object-oriented way. Our conclusions are drawn not only from a systematic review of related works but from an experimental scenario. For our experiment, we designed a simple CRM-compliant graph designed to test the ability of each OGM/database combination to tackle the so-called diamond-problem in Object-Oriented Programming (OOP) to ensure that property instances follow domain and range constraints. Our results show that (1) ontological consistency enforcement in graph databases and triplestores is much harder to achieve than in a relational database, making them more suited to an analytical rather than a transactional role; (2) OGMs are still rather immature solutions; and (3) neomodel, an OGM for the Neo4j graph database, is the most mature solution in the study as it satisfies all requirements, although it is also the least performing.

2021

CAT: content-aware tracing and analysis for distributed systems

Authors
Esteves, T; Neves, F; Oliveira, R; Paulo, J;

Publication
Middleware

Abstract

2021

A deductive reasoning approach for database applications using verification conditions

Authors
Alam, MI; Halder, R; Pinto, JS;

Publication
JOURNAL OF SYSTEMS AND SOFTWARE

Abstract
Deductive verification has gained paramount attention from both academia and industry. Although intensive research in this direction covers almost all mainstream languages, the research community has paid little attention to the verification of database applications. This paper proposes a comprehensive set of Verification Conditions (VCs) generation techniques from database programs, adapting Symbolic Execution, Conditional Normal Form, and Weakest Precondition. The validity checking of the generated VCs for a database program determines its correctness w.r.t. the annotated database properties. The developed prototype DBverify based on our theoretical foundation allows us to instantiate VC generation from PL/SQL codes, yielding to detailed performance analysis of the three approaches under different circumstances. With respect to the literature, the proposed approach shows its competence to support crucial SQL features (aggregate functions, nested queries, NULL values, and set operations) and the embedding of SQL codes within a host imperative language. For the chosen set of benchmark PL/SQL codes annotated with relevant properties of interest, our experiment shows that only 38% of procedures are correct, while 62% violate either all or part of the annotated properties. The primary cause for the latter case is mostly due to the acceptance of runtime inputs in SQL statements without proper checking.

2021

The CoronaSurveys System for COVID-19 Incidence Data Collection and Processing

Authors
Baquero, C; Casari, P; Anta, AF; García García, A; Frey, D; Garcia Agundez, A; Georgiou, C; Girault, B; Ortega, A; Goessens, M; Hernández Roig, HA; Nicolaou, N; Stavrakis, E; Ojo, O; Roberts, JC; Sanchez, I;

Publication
FRONTIERS IN COMPUTER SCIENCE

Abstract
CoronaSurveys is an ongoing interdisciplinary project developing a system to infer the incidence of COVID-19 around the world using anonymous open surveys. The surveys have been translated into 60 languages and are continuously collecting participant responses from any country in the world. The responses collected are pre-processed, organized, and stored in a version-controlled repository, which is publicly available to the scientific community. In addition, the CoronaSurveys team has devised several estimates computed on the basis of survey responses and other data, and makes them available on the project's website in the form of tables, as well as interactive plots and maps. In this paper, we describe the computational system developed for the CoronaSurveys project. The system includes multiple components and processes, including the web survey, the mobile apps, the cleaning and aggregation process of the survey responses, the process of storage and publication of the data, the processing of the data and the computation of estimates, and the visualization of the results. In this paper we describe the system architecture and the major challenges we faced in designing and deploying it.

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