Business model analysis of Mobitto: How to solve the chicken and egg problem of a multi-sided platform?

A Work Project, presented as part of the requirements for the Award of a Masters Degree in Management from the NOVA – School of Business and Economics

STRUCTURE-FUNCTION ANALYSIS OF MULTI-COPPER OXIDASES

Dissertation presented to obtain the Ph.D degree in Biochemistry, Structural Biochemistry

Regulation of gene expression by SnRK1 kinases and miRNAs during the plant stress response

Dissertation presented to obtain the Ph.D degree in Plant Physiology

Experimental high-throughput adsorption unit for multi-evaluation of adsorbents for gas capture, storage and separation applications

Dissertação para obtenção do grau de Mestre em Engenharia Química e Bioquímica

Optimização energética de sistemas multi-componente da zona fria do Steam Cracker

Dissertação para obtenção do Grau de Mestre em Engenharia Química e Bioquímica

Energy-efficient diversity combining for different access schemes in a multi-path dispersive channel

Dissertação para obtenção do Grau de Doutor em Engenharia Electrotécnica e Computadores

Aterragem de robôs aéreos multi-rotor em plataformas móveis: uma solução baseada em comportamentos e em saliência visual

Dissertação para obtenção do Grau de Mestre em Engenharia Eletrotécnica e de Computadores

Synchronization properties of multi-oscillator circadian systems

Dissertation presented to obtain the Ph.D degree in Computational Biology

Modelling of a wastewater treatment plant using GPS-X

Dissertation to obtain the degree of Master in Chemical and Biochemical Engineering

Context-based identification of energy consumption in industrial plants

Nowadays, reducing energy consumption is one of the highest priorities and biggest challenges faced worldwide and in particular in the industrial sector. Given the increasing trend of consumption and the current economical crisis, identifying cost reductions on the most energy-intensive sectors has become one of the main concerns among companies and researchers. Particularly in industrial environments, energy consumption is affected by several factors, namely production factors(e.g. equipments), human (e.g. operators experience), environmental (e.g. temperature), among others, which influence the way of how energy is used across the plant. Therefore, several approaches for identifying consumption causes have been suggested and discussed. However, the existing methods only provide guidelines for energy consumption and have shown difficulties in explaining certain energy consumption patterns due to the lack of structure to incorporate context influence, hence are not able to track down the causes of consumption to a process level, where optimization measures can actually take place. This dissertation proposes a new approach to tackle this issue, by on-line estimation of context-based energy consumption models, which are able to map operating context to consumption patterns. Context identification is performed by regression tree algorithms. Energy consumption estimation is achieved by means of a multi-model architecture using multiple RLS algorithms, locally estimated for each operating context. Lastly, the proposed approach is applied to a real cement plant grinding circuit. Experimental results prove the viability of the overall system, regarding both automatic context identification and energy consumption estimation.

Estudo do motor em disco com o rotor em alumínio e em supercondutor multi-semente

Nesta dissertação é realizado o estudo de um motor em disco polifásico com armadura convencional e rotor que pode ser convencional, em alumínio, ou composto por material supercondutor de alta temperatura multi‐semente. O motor com o rotor em alumínio apresenta um comportamento assíncrono bem definido, baseado na lei geral de indução de eletromotrizes no induzido. Contudo, ao ser mergulhado em azoto líquido, evidencia melhores características eléctricas, tanto do induzido como do indutor, mesmo que o núcleo ferromagnético convencional possa exibir degradação magnética. O motor com o rotor SAT exibe um comportamento distinto, evidenciando ambos os regimes síncrono e assíncrono estáveis. O regime síncrono fica caracterizado pelo fenómeno de aprisionamento de campo, que garante que o rotor gire síncrono com o campo girante do estator. Em regime assíncrono, para um determinado valor de binário resistente aplicado superior ao electromagnético máximo desenvolvido pelo motor, o fenómeno de escoamento de campo está presente, sendo o binário electromagnético motor reforçado por um binário extra de perdas de carácter resistivo desenvolvidas no rotor devido à interacção da densidade de corrente a campos eléctricos que se estabelecem no rotor. Neste caso, o fenómeno de escoamento de campo não é devido a forças de Lorentz que se definem na matriz de Abrikosov, mas sim devido a esta ser “puxada” pelo campo girante do estator, ficando a matriz a deslizar sobre o rotor. De modo a obter as características dos sistemas electromecânicos em estudo é realizada uma análise teórica, baseada na teoria convencional das máquinas eléctricas, com o objectivo de compreender alguns dos fenómenos do motor de fluxo axial, e uma análise baseada num programa comercial de elementos finitos onde o fenómeno da supercondutividade é simulado com base na relação entre o campo elétrico e a densidade de corrente pela lei da potenciação (E‐J power law). O ensaio dos motores referidos é realizado para comparar ambos os sistemas e de realçar o princípio de funcionamento e as características mais relevantes de cada um. Da análise realizada é desenvolvido um modelo que caracteriza o funcionamento da máquina com o rotor com SAT.

Integration of a mobile autonomous robot in a surveillance multi-agent system

This dissertation aims to guarantee the integration of a mobile autonomous robot equipped with many sensors in a multi-agent distributed and georeferenced surveillance system. The integration of a mobile autonomous robot in this system leads to new features that will be available to clients of surveillance system may use. These features may be of two types: using the robot as an agent that will act in the environment or by using the robot as a mobile set of sensors. As an agent in the system, the robot can move to certain locations when alerts are received, in order to acknowledge the underlying events or take to action in order to assist in resolving this event. As a sensor platform in the system, it is possible to access information that is read from the sensors of the robot and access complementary measurements to the ones taken by other sensors in the multi-agent system. To integrate this mobile robot in an effective way it is necessary to extend the current multi-agent system architecture to make the connection between the two systems and to integrate the functionalities provided by the robot into the multi-agent system.

An integrated approach to Physcomitrella patens transcriptomics reveals importantclues of the evolutionary development of plant organs and sexual reproduction

Land plant evolution required the generation of a new body plan that could resist the harsher and fluctuating environmental conditions found outside of aquatic environments. Unraveling the genetic basis of plant developmental innovations is not only revealing in terms of an evolutionary point of view, but it is also important for understanding the emergence of agronomically important traits. Comparative genetic studies between basal and modern land plants, both at the genome and trancriptome levels, can help in the generation of hypotheses related to the genetic basis of plant evolutionary development.(...)

Inhibition of SNF1-related protein kinase1 by trehalose 6-phosphate and other metabolites and the interrelation with plant gorwth

All life forms need to monitor carbon and energy availability to survive and this is especially true for plants which must integrate unavoidable environmental conditions with metabolism for cellular homeostasis maintenance. Sugars, in the heart of metabolism, are now recognized as crucial signaling molecules that translate those conditions. One such signal is trehalose 6- phosphate (T6P), a phosphorylated dimer of glucose molecules which levels correlate well with those of sucrose (Suc). Central integrators of stress and energy regulation include the conserved plant Snf1-related kinase1 (SnRK1) which respond to low cellular energy levels by up-regulating energy conserving and catabolic metabolism and down-regulating energy consuming processes. In 2009 T6P was shown to inhibit SnRK1. The in vitro inhibition of SnRK1 by T6P was confirmed in vivo through the observation that genes normally induced by SnRK1 were repressed by T6P and vice-versa, promoting growth processes. These observations provided a model for the regulation of growth by sugar.(...)

Use of multi-sensory marketing techniques and its influence on brand experience in retail and HORECA sector

Double degree. A Work Project presented as part of the requirements for the Award of a Masters Degree in Management from the NOVA- School of Business and Economics and Warsaw School of Economics