Desenvolvimento de um simulador de uma máquina florestal em realidade virtual

Computer-aided design (CAD) software is used in the product design and development to design complex and detailed prototypes. It provides good assistance and solid data generation to designers and engineers. In order to remain competitive, industry is always seeking for higher process efficiency and product quality enhancement in the shortest period of time. Continuous research keeps going to make it possible. Virtual reality has been one of the research focus in the recent years. It is studied and applied to be used as an assistant tool in the product lifecyle management, particularly in facilitating the development phase. However, the implementation process from CAD to virtual reality remains a challenge due to time consumption and technology complexibility. In this work a real-time virtual reality harvester simulator was developed. The start point was a 3D harvester CAD model. It was used the CAD simulator AGX Momentum, a game engine Unity and the physics engine AGX Dynamics to create dynamics simulation, to design a virtual forest environment and to enable physical controllers interact with the model. With the capabilities of AGX Momentum, it was added dynamics motion directly in the CAD software, creating fast CAD simulations. A virtual scene was designed with Unity to simulate an environment and the immersion of the user on it with Oculus Rift device. The harvester model was imported to the Unity scene with AGX Dynamics. In the end it was obtained a real size virtual prototype, with the possibility of interacting and control it using physical controllers. The user can visualise the scene in real-time through a head mounted display, providing him the experience of a real machine operator. Driving the harvester in a simulated forest, allowed to test the model in a hypothetical real scenario. The process of implementing the CAD model in virtual reality used in this work, revealed to be efficient and intuitive. However, because it is a complex and large model, it was necessary to remove certain bodies (without dynamics effect) and reduce the number of contact points between components in order to balance the speed and performance of the simulator. Following the same method used in this work, Other CAD models can be imported to virtual reality and be dynamically simulated.Software de desenho assistido por computador – do inglês, computer aided design (CAD) é usado no processo de desenvolvimento e design de produto para projetar protótipos complexos e detalhados. Este tipo de software fornece boa assistência e gera consistentes dados de modelos para designers e engenheiros. Com vista a manter-se competitiva, a indústria está sempre à procura de uma maior eficiência do processo e de uma melhoria da qualidade do produto a desenvolver no menor perı́odo de tempo possı́vel. A investigacão, nos últimos anos e em curso, tem tentado tornar isto possı́vel. A realidade virtual tem sido um dos focos dessa investigação. Tem sido estudada e aplicada para ser usada como ferramenta auxiliar na gestão do ciclo de vida do produto, em particular na facilitação da fase de desenvolvimento. Contudo, o processo de implementação do CAD em realidade virtual continua a ser um desafio devido quer à complexidade tecnológica envolvida, quer ao tempo requerido. Neste trabalho foi desenvolvido um simulador de tempo real a partir de uma máquina florestal harvester em realidade virtual. O ponto de partida consistiu num modelo CAD da máquina. Para isso, foi utilizado o simulador CAD AGX Momentum, o motor de jogo Unity e o motor de fı́sica AGX Dynamics para adicionar dinâmica ao modelo, criar um ambiente virtual de uma floresta e permitir que controladores fı́sicos interagissem com o protótipo. Com os recursos de AGX Momentum, foi adicionado movimento dinâmico diretamente no software CAD, criando rápidas simulações. Através do Unity, foi projetado um cenário virtual para simular um ambiente virtual e promover a imersão do utilizador com o dispositivo Oculus Rift. O modelo da harvester foi, depois, importado para a “cena” com AGX Dynamics. No final, foi obtido um protótipo virtual em tamanho real, com a possibilidade de interagir e ser controlado usando comandos fı́sicos. O utilizador pode visualizar a cena em tempo real através de um dispositivo de realidade virtual, proporcionando-lhe a experiência de um real operador da máquina. Ao conduzir a harvester numa floresta virtual, permitiu testar o modelo num cenário hipoteticamente real. O processo de implementação do modelo CAD em realidade virtual utilizado neste trabalho revelou-se eficiente e intuitivo. No entanto, por se tratar de um modelo complexo e extenso, foi necessário remover determinados sólidos (sem interferência dinâmica) e reduzir o número de pontos de contacto entre componentes para equilibrar a velocidade e desempenho do simulador. Seguindo o mesmo método utilizado neste trabalho, outros modelos CAD podem ser importados para a realidade virtual e ser dinamicamente simulados.Mestrado em Engenharia Mecânic

Physiologic Basis and Pathophysiologic Implications of the Diastolic Properties of the Cardiac Muscle

Although systole was for long considered the core of cardiac function, hemodynamic performance is evenly dependent on appropriate systolic and diastolic functions. The recognition that isolated diastolic dysfunction is the major culprit for approximately fifty percent of all heart failure cases imposes a deeper understanding of its underlying mechanisms so that better diagnostic and therapeutic strategies can be designed. Risk factors leading to diastolic dysfunction affect myocardial relaxation and/or its material properties by disrupting the homeostasis of cardiomyocytes as well as their relation with surrounding matrix and vascular structures. As a consequence, slower ventricular relaxation and higher myocardial stiffness may result in higher ventricular filling pressures and in the risk of hemodynamic decompensation. Thus, determining the mechanisms of diastolic function and their implications in the pathophysiology of heart failure with normal ejection fraction has become a prominent field in basic and clinical research

Personalização de um curriculum vitae

Mestrado em Engenharia de Computadores e TelemáticaO presente trabalho propõe-se estudar um modelo de criação e manutenção de um curriculum vitae via web, tendo por base o sistema já existente na Universidade de Aveiro. Este engloba o estudo das diversas alternativas de armazenamento de um curriculum vitae, a verificação da actualidade do sistema actualmente existente, bem como quais as vantagens e inconvenientes de outras alternativas. Como resultado, pretende-se completar o sistema existente na Universidade de Aveiro, preenchendo as eventuais lacunas que este possa possuir ou efectuando melhorias/acrescentando funcionalidades que estejam presentes noutros sistemas do género. ABSTRACT: The present work has the purpose of studying the actuality of a model of generation of a CV via web, the similar systems, as well as to develop new functionalities in a way to complete the system already in existence. The study of the actuality includes the alternatives of storage of a CV, the verification of actuality of the used system as well as the advantages and inconveniences of other alternatives. It is intended, as well, to complete the system of Aveiro’s University fulfilling the eventual gaps that the system might possess or by making improvements/adding functionalities that are present in other similar systems

Specific evolution and gene family expansion of complement 3 and regulatory factor H in fish

The complement system comprises a large family of plasma proteins that play a central role in innate and adaptive immunity. To better understand the evolution of the complement system in vertebrates and the contribution of complement to fish immunity comprehensive in silico and expression analysis of the gene repertoire was made. Particular attention was given to C3 and the evolutionary related proteins C4 and C5 and to one of the main regulatory factors of C3b, factor H (Cfh). Phylogenetic and gene linkage analysis confirmed the standing hypothesis that the ancestral c3/c4/c5 gene duplicated early. The duplication of C3 (C3.1 and C3.2) and C4 (C4.1 and C4.2) was likely a consequence of the (1R and 2R) genome tetraploidization events at the origin of the vertebrates. In fish, gene number was not conserved and multiple c3 and cfh sequence related genes were encountered, and phylogenetic analysis of each gene generated two main clusters. Duplication of c3 and cfh genes occurred across the teleosts in a species-specific manner. In common, with other immune gene families the c3 gene expansion in fish emerged through a process of tandem gene duplication. Gilthead sea bream (Sparus aurata), had nine c3 gene transcripts highly expressed in liver although as reported in other fish, extra-hepatic expression also occurs. Differences in the sequence and protein domains of the nine deduced C3 proteins in the gilthead sea bream and the presence of specific cysteine and N-glycosylation residues within each isoform was indicative of functional diversity associated with structure. The diversity of C3 and other complement proteins as well as Cfh in teleosts suggests they may have an enhanced capacity to activate complement through direct interaction of C3 isoforms with pathogenic agents.(FCT) project to CCMAR (UIDB/04326/2020)info:eu-repo/semantics/publishedVersio

Meadow management hay yields and nutritive value in the Mediterranean mountain regions of the Northeast of Portugal

To evaluate the possibility of improving hay nutritive value, six hay meadows were studied in the Northeast of Portugal from 1998 to 2000. The treatments were fertilization rates of O, 75 and 150 kg N/ha/y in combination with two cutting/grazing regimes: the usual for the area (NG) and a larger spring grazing period with meadows closed off for hay three weeks later (LG). Their effects on crude protein content, in vitro organic matter digestibility, and dry-matter, crude protein and metabolizable energy yields were evaluated. The treatments studied significantly influenced the parameters evaluated. Late spring grazing induced the greatest changes in the highest yielding meadows (M3 and M5) increasing nutritive values but decreasing the DM yield (-2t DM/ha, + 1 % CP and +3% IVOMD). However, the positive influences on CP content and IVOMD are not high enough to overcome the low values (Iess than 10% CP and 50% IVOMD) observed in meadows with hay growth periods longer than 60-70 day

Distribution and risk assessment of potential invasiveness of Australoheros facetus (Jenyns, 1842) in Portugal

Invasive species are recognized as a major cause of biodiversity decline. Legal regulations relating to the prevention, control, or eradication of invasive species should always be up-to-date, as the failure to recognize the problem, lack of adequate scientific information, or long legal intervals required to prepare the legislation may result in irreversible, possibly catastrophic, outcomes. This implies constant monitoring of the species distribution and levels of establishment, as well as detailed knowledge about its biology to predict dissemination and viability under changing environmental conditions. Pre-screening kits for potential invasive species are valuable tools for policy makers, as they provide information about if and how management measures should be taken. The Freshwater Fish Invasiveness Scoring Kit (FISK) and the Aquatic Species Invasiveness Screening Kit (AS-ISK) have been suggested as reliable tools to assess the potential risk of a species becoming invasive. The present study highlights the spread of the non-native chameleon cichlid Australoheros facetus in several streams of the major river drainages in southern Portugal and compares the fish assemblages and ecological indices in two selected sites in the Vascão and Odelouca rivers. We reviewed the current knowledge on the distribution, physiology, and behavior of A. facetus, and applied the toolkits FISK v2 and AS-ISK to this species to evaluate whether the species should be classified as invasive in Portugal. Field data show high abundance of the species in most streams and dominance in specific hotspots. The scores reached by the kits (FISK v2: 23; AS-ISK: 37) places A. facetus as a species with high potential of invasiveness and support the recent inclusion of this species in the invasive species list in Portugal (Decree-Law 92/2019), but, most of all, highlights the importance of frequent updates in both the field monitoring and the legal regulation and watch lists of invasive organisms.Program Science without Borders (245971/2012-2); FCT—Foundation for Science and Technology through project UID/Multi/04326/2019.info:eu-repo/semantics/publishedVersio