Análise de Programas de Extensão de Vida e Optimização do seu Phase-Out

A Força Aérea Portuguesa opera algumas aeronaves que se encontram numa fase avançada do seu ciclo de vida. Estas aeronaves apresentam muitos problemas resultantes do desgaste em operação e dos mecanismos do envelhecimento. Estes problemas conduzem a acções de manutenção e de monitorização permanente das frotas, através de programas específicos de acompanhamento que não foram previstos pelo fabricante na fase de projecto da aeronave. Para que a metodologia de manutenção adoptada seja adequada às necessidades operacionais e coerente com o envelhecimento das frotas, há que ter em conta alguns factores os quais, se devidamente analisados, conduzirão à extensão de vida de uma frota e à sua operação segura. Pretende-se com este trabalho de investigação obter mais conhecimento sobre a temática da gestão do envelhecimento das aeronaves e sobre os factores que contribuem para a tomada de uma determinada decisão relativamente a um sistema de aeronave ou a uma aeronave, que conduza à sua reparação, modernização ou retirada de serviço, em determinadas fases do seu ciclo de vida e que conduzem a um programa de gestão bem definido, estruturado e ajustado. A gestão do envelhecimento de aeronaves deve resultar de um processo que permita identificar problemas desse envelhecimento, da manutenção, dos recursos e das capacidades técnicas e logísticas, todos eles influentes na gestão de longos ciclos de vida na aviação. Gerir o envelhecimento de aeronaves não diz respeito apenas à segurança de voo, à disponibilidade de meios ou à economia de recursos. Diz respeito a um melhoramento contínuo e adaptado da manutenção das aeronaves, através de uma atitude pró-activa e reactiva, a qual permite acompanhar e sustentar as aeronaves por 20, 30 ou mais anos, excedendo por um período muito longo o seu ciclo de vida inicialmente previsto. Há que fazer uma previsão adequada de custos para uma frota envelhecida, de acordo com as necessidades operacionais, a fim de elaborar um plano de custos detalhado com a maior antecedência possível. No entanto, deverá ser avaliada a relação custo/benefício de uma determinada acção, pois esta pode não se justificar a prazo. Deverá ser analisado o período de rentabilização do investimento que, no máximo, deverá ser igual ao período de operação remanescente para a plataforma em causa. Os modelos analisados neste trabalho reflectem as metodologias utilizadas por outros operadores no acompanhamento de frotas sujeitas a mecanismos de envelhecimento em fases avançadas do seu ciclo de vida. A pesquisa efectuada baseou-se principalmente em artigos relacionados com gestão do envelhecimento de aeronaves, com o objectivo de validar as hipóteses que permitirão dar resposta às perguntas derivadas e à pergunta de partida. Abstract: The Portuguese Air Force operates some aircrafts in an advanced phase of its life cycle. These aircraft present many problems resulting from the mechanisms of aging. These problems lead to additional maintenance procedures and permanent monitoring of the fleets, through specific programs of support that had not been foreseen by the manufacturer in the project of the aircraft. So, the maintenance methodology adopted is adjusted to the operational needs and should be coherent with the aging of the fleets, taking in account some factors which, if duly analyzed, will lead to the safe operation of a fleet for long periods of time. It is intended with this work to get more knowledge on the thematic of the management of aircraft aging and on the factors that contribute to take a decision concerning a system of aircraft or an aircraft itself, that leads to its repair, mid life update program or phase-out in any phases of its life cycle. These factors will lead to an optimal management program. The management of aircraft aging must result of a process that allows to identify problems of aging, maintenance, resources, logistic and technical capabilities, all influent in the management of long life cycles in aviation. The management of aircraft aging is not only a matter of flight safety, availability or economy of resources. It respects to a continuous and adapted improvement of the maintenance of the aircraft, through an proactive and reactive attitude, which allows to follow and to support the aircraft for 20, 30 or more years, exceeding for a very long period its initial life cycle. It’s very important an adequate plan of costs for an aged fleet, in accordance with the operational needs. The period of recovery of the investment will have to be analyzed and, in the maximum, will have to be equal to the period of remaining operation for the platform in cause. The models analyzed in this work reflect the methodologies used by other operators in the accompaniment of their fleets, to overcome the mechanisms of aging in advanced phases of its life cycle. The research was based mainly on articles related with management of aircraft aging, with the objective to validate the hypotheses that would allow to give the answers to the principal and secondary questions

Extensões via splines da análise em componentes principais

Uma nova abordagem para generalizar a Análise em Componentes Principais (ACP) para estruturas não-lineares é proposta nesta tese: quasi-linear PCA (qlPCA). Esta inclui transformações spline das variáveis originais optimizadas através de um processo de Mínimos Quadrados Alternados sobre uma determinada função perda. As transformações óptimas são explicitamente conhecidas após a convergência, sendo o sumário do modelo semelhante ao da ACP. Apesar do algoritmo proposto ser dedicado a ambientes de variáveis contínuas com eventual presença de relações não-lineares, a sua inspiração foram os algoritmos que emergiram do sistema Gifi, tendo estes sido especialmente concebidos para variáveis categoriais. Deste ponto de vista, pode afirmar-se que esta tese propõe uma solução para o seguinte problema: Tendo as variantes da ACP associadas ao sistema Gifi sido desenvolvidas para variáveis categoriais, como adaptá- -las de modo a serem consideradas como uma abordagem não-linear em contexto de variáveis contínuas? As variantes associadas ao sistema Gifi não são usualmente abordagens a considerar pelos investigadores de áreas do conhecimento que lidem com vari´aveis cont´ınuas. Nesse sentido, considera-se que a qlPCA representa um contributo relevante, alargando o leque de aplica¸c˜oes do referencial te´orico desenvolvido por Gifi.A new approach to generalize Principal Components Analysis (PCA) in order to handle nonlinear structures is proposed in this thesis: quasi-linear PCA (qlPCA). It includes spline transformations of the original variables, using Alternating Least Squares fitting of a suitable objective loss function to achieve optimal transformations. Optimal transformations are explicitly known after convergence and qlPCA reports model summary in a linear PCA fashion. Even though the proposed algorithm is designed for continuous variables eventually with nonlinear relationships, it was inspired by algorithms that emerged from the Gifi system, whose focus were categorical variables. Thus, this thesis proposes a solution for the following problem: Having Gifi’s related approaches been developed for categorical variables, how to adapt them in order to be considered a nonlinear option also in the context of continuous variables? Gifi’s related approaches are not usually a valid option for researchers dealing with continuous variables. The proposed approach, qlPCA, can enlarge the scope of applications of Gifi’s theoretical framework, being therefore a relevant contribution

Retrospective analysis of soft tissue injuries treated with allogenic bone marrow derived mesenchymal stem cells

Objectives: Tendon and ligament pathology has been managed successfully with mesenchymal stem cells from various biological sources. This retrospective study aims to evaluate the re-injury rate of the treatment of tendon and ligament lesions with allogenic bone marrow derived mesenchymal stem cells (BM-MSCs). Methods: Data from horses treated with allogenic BM- MSCs was recovered retrospectively from hospital records. Horses were included if they were solely treated with BM- MSCs, received only one treatment, had no other concur- rent lesion at the time of treatment, and had sufficient information about lameness and ultrasound evaluations. Outcome was evaluated in terms of re-injury within 12 months after treatment. Frequency counts were calcu- lated, and a chi-square test of homogeneity was used to determine whether distribution was identical across differ- ent disciplines and different anatomic structures. Results: Forty-two horses were included: 8 show jum- pers, 15 dressage horses, 15 Standardbreds and 7 leisure horses. There were 22 digital flexor tendons and 20 liga- ment injuries. The overall re-injury rate was 33%. No sta- tistical evidence was found to conclude that re-injury rate was influenced by discipline (p-value = 0.987) or ana- tomic structure (p-value = 0.592). No adverse reactions were observed on the treated horses. Conclusions: The treatment was safe, and re-injury rate was lower than reported when using conventional thera- pies. Our sample suggests that re-injury rate is the same across the different disciplines and anatomic structures. Further studies should be conducted, imposing a larger sample size and a control group

Qualidade de Vida e Participação em Iniciativas de Base Comunitária: Um estudo num município da zona centro de Portugal

Face ao reconhecimento da importância da participação social como fator promotor de envelhecimento bem-sucedido, procura-se, através de um estudo de natureza quantitativo, analisar os efeitos de variáveis sociodemográficas e da participação social em atividades/programas de base comunitária, promovidas por um município da zona centro de Portugal, ao nível da qualidade de vida de pessoas com mais de 56 anos, residentes no concelho.info:eu-repo/semantics/publishedVersio

Clinical Presentation and Long-Term Outcomes of Systemic Sclerosis Portuguese Patients from a Single Centre Cohort: A EUSTAR Registration Initiative

Introduction: Systemic sclerosis is a complex disorder that requires systematic screening. Our objective is to report the European Scleroderma Trials and Research group centre affiliation and its impact in our clinical practice. Material and Methods: The European Scleroderma Trials and Research group affiliation process, database update and current patient evaluation, with respect to demographic and clinical features. Cumulative mortality was analysed. Results: We identified 19 female patients (which met all the American College of Rheumatology/ European League Against Rheumatism 2013 criteria for systemic sclerosis) under current follow-up, divided according to the LeRoy classification into diffuse cutaneous (n = 5), limited cutaneous (n = 11) and limited (n = 3) types, followed for a median period of 5, 12 and 6 years, respectively. Raynaud´s phenomenon and abnormal nailfold capillaries were universally present. Interstitial lung disease was absent in the limited cutaneous form but present in 100% of the diffuse subtype. Pitting scars were more common in the diffuse form. Active disease was also more frequent in the diffuse form, and most patients with active disease were treated with anti-endothelin receptor antagonists. Over 21 years (from 1994 to 2015) the mortality rate was 55% (n = 23/42). Age at time of death was significantly lower in the diffuse subtype. Discussion: Our single centre cohort shares many features with larger and international reports and more specifically is in accordance with patient characteristics described in the European Scleroderma Trials and Research group registries. Conclusion: The European Scleroderma Trials and Research group registration motivated our systematic patient characterization and may be used as a tool for homogenous disease registries

Erratum to “Clinical Presentation and Long-Term Outcomes of Systemic Sclerosis Portuguese Patients from a Single Centre Cohort: A EUSTAR Registration Initiative”

Article published with errors: https://www.actamedicaportuguesa.com/revista/index.php/amp/article/view/10658 On page 312, where the authors’ line reads as: Carolina VIDAL1, Carina RUANO2, Vera BERNARDINO3, Pedro LAVADO CARREIRA3, Ana LLADÓ3, Maria Céu SANTOS4, Heidi GRUNER3, António PANARRA3, Nuno RISO3, Maria Francisca MORAES-FONTESAC,1 It should read: Carolina VIDAL1,2, Carina RUANO3, Vera BERNARDINO1, Pedro LAVADO CARREIRA1, Ana LLADÓ1, Maria Céu SANTOS4, Heidi GRUNER1, António PANARRA1, Nuno RISO1, Maria Francisca MORAES-FONTESAC,1   On the same page, where the authors’ affiliation on the footer reads as: • Serviço de Medicina Interna. Hospital do Divino Espírito Santo de Ponta Delgada. São Miguel. Portugal. • Serviço de Radiologia. Hospital de Santa Marta. Centro Hospitalar de Lisboa Central. Lisboa. Portugal. • Unidade de Doenças Auto-Imunes/Serviço Medicina 7.2. Hospital de Curry Cabral. Centro Hospitalar de Lisboa Central. Lisboa. Portugal. • Laboratório de Imunologia. Centro Hospitalar de Lisboa Central. Lisboa. Portugal.  It should read: • Unidade de Doenças Auto-Imunes/Serviço Medicina 7.2. Hospital de Curry Cabral. Centro Hospitalar de Lisboa Central. Lisboa. Portugal. • Serviço de Medicina Interna. Hospital do Divino Espírito Santo de Ponta Delgada. São Miguel. Portugal. • Serviço de Radiologia. Hospital de Santa Marta. Centro Hospitalar de Lisboa Central. Lisboa. Portugal. • Laboratório de Imunologia. Centro Hospitalar de Lisboa Central. Lisboa. Portugal

SARS-CoV-2 introductions and early dynamics of the epidemic in Portugal

Genomic surveillance of SARS-CoV-2 in Portugal was rapidly implemented by the National Institute of Health in the early stages of the COVID-19 epidemic, in collaboration with more than 50 laboratories distributed nationwide. Methods By applying recent phylodynamic models that allow integration of individual-based travel history, we reconstructed and characterized the spatio-temporal dynamics of SARSCoV-2 introductions and early dissemination in Portugal. Results We detected at least 277 independent SARS-CoV-2 introductions, mostly from European countries (namely the United Kingdom, Spain, France, Italy, and Switzerland), which were consistent with the countries with the highest connectivity with Portugal. Although most introductions were estimated to have occurred during early March 2020, it is likely that SARS-CoV-2 was silently circulating in Portugal throughout February, before the first cases were confirmed. Conclusions Here we conclude that the earlier implementation of measures could have minimized the number of introductions and subsequent virus expansion in Portugal. This study lays the foundation for genomic epidemiology of SARS-CoV-2 in Portugal, and highlights the need for systematic and geographically-representative genomic surveillance.We gratefully acknowledge to Sara Hill and Nuno Faria (University of Oxford) and Joshua Quick and Nick Loman (University of Birmingham) for kindly providing us with the initial sets of Artic Network primers for NGS; Rafael Mamede (MRamirez team, IMM, Lisbon) for developing and sharing a bioinformatics script for sequence curation (https://github.com/rfm-targa/BioinfUtils); Philippe Lemey (KU Leuven) for providing guidance on the implementation of the phylodynamic models; Joshua L. Cherry (National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health) for providing guidance with the subsampling strategies; and all authors, originating and submitting laboratories who have contributed genome data on GISAID (https://www.gisaid.org/) on which part of this research is based. The opinions expressed in this article are those of the authors and do not reflect the view of the National Institutes of Health, the Department of Health and Human Services, or the United States government. This study is co-funded by Fundação para a Ciência e Tecnologia and Agência de Investigação Clínica e Inovação Biomédica (234_596874175) on behalf of the Research 4 COVID-19 call. Some infrastructural resources used in this study come from the GenomePT project (POCI-01-0145-FEDER-022184), supported by COMPETE 2020 - Operational Programme for Competitiveness and Internationalisation (POCI), Lisboa Portugal Regional Operational Programme (Lisboa2020), Algarve Portugal Regional Operational Programme (CRESC Algarve2020), under the PORTUGAL 2020 Partnership Agreement, through the European Regional Development Fund (ERDF), and by Fundação para a Ciência e a Tecnologia (FCT).info:eu-repo/semantics/publishedVersio

Counting People and Bicycles in Real Time Using YOLO on Jetson Nano

Counting objects in video images has been an active area of computer vision for decades. For precise counting, it is necessary to detect objects and follow them through consecutive frames. Deep neural networks have allowed great improvements in this area. Nonetheless, this task is still a challenge for edge computing, especially when low-power edge AI devices must be used. The present work describes an application where an edge device is used to run a YOLO network and V-IOU tracker to count people and bicycles in real time. A selective frame-downsampling algorithm is used to allow a larger frame rate when necessary while optimizing memory usage and energy consumption. In the experiments, the system was able to detect and count the objects with 18 counting errors in 525 objects and a mean inference time of 112.82 ms per frame. With the selective downsampling algorithm, it was also capable of recovering and reduce memory usage while maintaining its precision

Offline Handwritten Signature Verification Using Deep Neural Networks

Prior to the implementation of digitisation processes, the handwritten signature in an attendance sheet was the preferred way to prove the presence of each student in a classroom. The method is still preferred, for example, for short courses or places where other methods are not implemented. However, human verification of handwritten signatures is a tedious process. The present work describes two methods for classifying signatures in an attendance sheet as valid or not. One method based on Optical Mark Recognition is general but determines only the presence or absence of a signature. The other method uses a multiclass convolutional neural network inspired by the AlexNet architecture and, after training with a few pieces of genuine training data, shows over 85% of precision and recall recognizing the author of the signatures. The use of data augmentation and a larger number of genuine signatures ensures higher accuracy in validating the signatures

Offline Handwritten Signature Verification Using Deep Neural Networks

Prior to the implementation of digitisation processes, the handwritten signature in an attendance sheet was the preferred way to prove the presence of each student in a classroom. The method is still preferred, for example, for short courses or places where other methods are not implemented. However, human verification of handwritten signatures is a tedious process. The present work describes two methods for classifying signatures in an attendance sheet as valid or not. One method based on Optical Mark Recognition is general but determines only the presence or absence of a signature. The other method uses a multiclass convolutional neural network inspired by the AlexNet architecture and, after training with a few pieces of genuine training data, shows over 85% of precision and recall recognizing the author of the signatures. The use of data augmentation and a larger number of genuine signatures ensures higher accuracy in validating the signatures