On the application of optimal control techniques in lossy fieldbuses

The performance of real-time networks is under continuous improvement as a result of several trends in the digital world. However, these tendencies not only cause improvements, but also exacerbates a series of unideal aspects of real-time networks such as communication latency, jitter of the latency and packet drop rate. This Thesis focuses on the communication errors that appear on such realtime networks, from the point-of-view of automatic control. Specifically, it investigates the effects of packet drops in automatic control over fieldbuses, as well as the architectures and optimal techniques for their compensation. Firstly, a new approach to address the problems that rise in virtue of such packet drops, is proposed. This novel approach is based on the simultaneous transmission of several values in a single message. Such messages can be from sensor to controller, in which case they are comprised of several past sensor readings, or from controller to actuator in which case they are comprised of estimates of several future control values. A series of tests reveal the advantages of this approach. The above-explained approach is then expanded as to accommodate the techniques of contemporary optimal control. However, unlike the aforementioned approach, that deliberately does not send certain messages in order to make a more efficient use of network resources; in the second case, the techniques are used to reduce the effects of packet losses. After these two approaches that are based on data aggregation, it is also studied the optimal control in packet dropping fieldbuses, using generalized actuator output functions. This study ends with the development of a new optimal controller, as well as the function, among the generalized functions that dictate the actuator’s behaviour in the absence of a new control message, that leads to the optimal performance. The Thesis also presents a different line of research, related with the output oscillations that take place as a consequence of the use of classic co-design techniques of networked control. The proposed algorithm has the goal of allowing the execution of such classical co-design algorithms without causing an output oscillation that increases the value of the cost function. Such increases may, under certain circumstances, negate the advantages of the application of the classical co-design techniques. A yet another line of research, investigated algorithms, more efficient than contemporary ones, to generate task execution sequences that guarantee that at least a given number of activated jobs will be executed out of every set composed by a predetermined number of contiguous activations. This algorithm may, in the future, be applied to the generation of message transmission patterns in the above-mentioned techniques for the efficient use of network resources. The proposed task generation algorithm is better than its predecessors in the sense that it is capable of scheduling systems that cannot be scheduled by its predecessor algorithms. The Thesis also presents a mechanism that allows to perform multi-path routing in wireless sensor networks, while ensuring that no value will be counted in duplicate. Thereby, this technique improves the performance of wireless sensor networks, rendering them more suitable for control applications. As mentioned before, this Thesis is centered around techniques for the improvement of performance of distributed control systems in which several elements are connected through a fieldbus that may be subject to packet drops. The first three approaches are directly related to this topic, with the first two approaching the problem from an architectural standpoint, whereas the third one does so from more theoretical grounds. The fourth approach ensures that the approaches to this and similar problems that can be found in the literature that try to achieve goals similar to objectives of this Thesis, can do so without causing other problems that may invalidate the solutions in question. Then, the thesis presents an approach to the problem dealt with in it, which is centered in the efficient generation of the transmission patterns that are used in the aforementioned approaches.

Secure Tropos: A Security-Oriented Extension of the Tropos methodology

Although security plays an important role in the development of multiagent systems, a careful analysis of software development processes shows that the definition of security requirements is, usually, considered after the design of the system. One of the reasons is the fact that agent oriented software engineering methodologies have not integrated security concerns throughout their developing stages. The integration of security concerns during the whole range of the development stages can help towards the development of more secure multiagent systems. In this paper we introduce extensions to the Tropos methodology to enable it to model security concerns throughout the whole development process. A description of the new concepts and modelling activities is given along with a discussion on how these concepts and modelling activities are integrated to the current stages of Tropos. A real life case study from the health and social care sector is used to illustrate the approach.

A Psychological Exploration of Long-Term LSD Users

All research involving the psychoactive compound lysergic acid diethylamide (LSD) was terminated globally following its prohibition more than 50 years ago, though illicit use remained fairly stable. A considerable resurgence of research interest in LSD has received considerable attention in various publications and professional fora. One of the main applications considered is LSD-assisted psychotherapy to address a number of difficulties like end-of-life anxiety, addiction/alcoholism, post-traumatic stress, and depression. However, due to the highly contradictory nature of early research findings and division in the literature, one is left uncertain as to whether psychology as a profession is currently equipped to critically evaluate these advances, let alone embrace them. The purpose of the present study was to contribute to current psychological knowledge on long-term LSD use. A group of long-term LSD users who claimed beneficial use were the focus here. A mixed methods design was employed. 110 users completed an online survey assessing for demographics, patterns of use, and specific personality traits through three psychometric measures, Big Five Inventory (BFI), General Self Efficacy scale (GSE) and Satisfaction With Life Scale (SWLS). Eight individual interviews were also conducted and analysed by Thematic Analysis (TA). Gaining different perspectives on reality and increasing self- awareness appeared to be essential elements of the belief system that these non-problematic long-term LSD users adopted in order to make sense of their LSD use. Qualitative findings also suggested the existence of a common set of life values, rules and the adoption of a hierarchical system between LSD users. Novices appeared to be tutored and guided by elders whose presence and input was valued and who were listened to and respected. A role for ‘wiser/elder’ users as those imparting valuable knowledge to novices was therefore also suggested. The underlying aim may possibly be an attempt to minimise risks and maximise potential benefits of LSD use. A prospective role for LSD as a deterrent of substance misuse, a ‘gateway drug to no drugs’ was also hinted and remains in need of iv further investigation. Claims regarding beneficial LSD use and ‘change’ through LSD use were confirmed by the participant sample. No noteworthy differences between psychometric scores of the LSD-using group and those of the general population (as suggested by normative data comparisons) were found, possibly due to methodological limitations, especially considering the highly subjective nature of the LSD experience and its effects. The determining role of extra-pharmacological variables or ‘set and setting’ in the outcome of LSD use suggested in earlier literature was re-validated. Knowledge on their specific components was enriched, and a potentially significant value for adopting a flexible, adaptable and solution-focused mind-set in order to better manage the effects of LSD was highlighted. Due to the highly selected nature of the participant sample, present findings should serve as suggestions for further research in order to clarify the aforementioned issues and to make explicit the mechanisms by which they operate. The complex nature of LSD, its use and its effects have been re-confirmed here. It is imperative that the current knowledge base on the substance is enriched before LSD is introduced in a clinical psychology professional context.

Estimating fuzzy membership functions parameters by the levenberg-marquardt algorithm

In previous papers from the authors fuzzy model identification methods were discussed. The bacterial algorithm for extracting fuzzy rule base from a training set was presented. The Levenberg-Marquardt algorithm was also proposed for determining membership functions in fuzzy systems. In this paper the Levenberg-Marquardt technique is improved to optimise the membership functions in the fuzzy rules without Ruspini-partition. The class of membership functions investigated is the trapezoidal one as it is general enough and widely used. The method can be easily extended to arbitrary piecewise linear functions as well.

Sediment dynamics and tidal inlet relocation in mixed-energy settings: the case of Ancão inlet (Algarve - Portugal)

Tese de dout., Ciências do Mar, Faculdade de Ciências do Mar e do Ambiente, Univ. do Algarve, 2003

Chromatographic analysis and comparison of chemical composition of the samples between olive oils in Europe and some chinese oils

Dissertação de mest., Qualidade em Análises, Faculdade de Ciências e Tecnologia, Univ. do Algarve, 2013

Entomofauna associated with the olive tree in southern Portugal

Since 2004 several studies have been carried out in order to identify the main insect species that usually inhabiting the olive ecosystem. The field trials have taken place in two olive groves, one situated in Olhão and the other one in Loulé, both in Algarve and also under Integrated Pest Management (IPM). The sampling techniques used differ according to their purpose (sticky traps, pheromone traps, pitfall traps and samples of aerial parts of the trees such as inflorescences, leaves, fruits and branches). Results showed that the main insect pests of olive tree in southern Portugal were the olive fruit fly Bactrocera oleae Gmelin (Diptera: Tephritidae) and the olive moth Prays oleae Bernard (Lepidoptera: Hyponeumetidae). Other insect pests were also found in our olive groves namely the olive psyllid Euphyllura olivina Costa (Homoptera: Psyllidae), the olive dark beetle Phloeotribus scarabaeoides Bernard (Coleoptera: Curculionidae), the mediterranean black scale Saissetia oleae (Olivier) (Homoptera: Coccidae) and the olive thrip Liothripes oleae Costa (Thysanoptera: Phlaeothripidae). Concerning the auxiliary insects that were found in our olives groves they belong to the following orders and families: Diptera (Syrphidae), Coleoptera (Carabidae, Coccinelidae and Staphylinidae), Hemiptera (Anthocoridae and Miridae), Neuroptera (Chrysopidae) and Hymenoptera (Braconidae, Encyrtidae, Eulophidae, Formicidae and Trichogrammatidae).

O grande carnaval, visão do jornalismo por Billy Wilder

Ace in the hole /The big Carnival (O Grande Carnaval 1951) foi o primeiro fracasso comercial da carreira de Billy Wilder. A crítica e o público da altura não se encantaram com a história sórdida protagonizada por um jornalista corrupto e imoral. O realizador austríaco tinha no currículo dois filmes premiados com Óscares, The lost weekend (Farrapo Humano 1945) e Sunset Boulevard (Crepúsculo dos Deuses 1950). Arriscou em terreno inexplorado ao invés de procurar a segurança em guiões menos complexos. A questão levanta-se: qual o motivo que levou Billy Wilder a dirigir uma obra inspirada num acontecimento mediático real (o caso Floyd Collins) e dessa forma expôr o que há de pior no jornalismo: o sensacionalismo, o excesso, a manipulação da verdade, a ausência de ética, a sede de lucro? O trabalho a que me propus tenta encontrar uma resposta através da análise do filme, à luz da vida e do cinema de Billy Wilder. Pretendo contar, nas páginas que se seguem, de que forma o cineasta adaptou à tela um caso verídico e qual a visão que deixou às gerações vindouras do jornalismo popular.

The role of alpha-synuclein phosphorylation in synucleinopathies

Tese de doutoramento, Ciências Biomédicas (Neurociências), Universidade de Lisboa, Faculdade de Medicina, 2014

Genetic characterization of the South Portugal population with GlobalFilerTM Express kit - internal validation and forensic applications

Tese de mestrado. Biologia (Biologia Humana e Ambiente). Universidade de Lisboa, Faculdade de Ciências, 2014

Variation of the Group 5 Grass Pollen Allergen Content of Airborne Pollen in Relation to Geographical Location and Time in Season

Allergies to grass pollen are the number one cause of outdoor hay fever. The human immune system reacts with symptoms to allergens from pollen. Objective: We investigated the natural variability in release of the major group 5 allergen from grass pollen across Europe. Methods: Airborne pollen and allergens were simultaneously collected daily with a volumetric spore trap and a high-volume cascade impactor at 10 sites across Europe for 3 consecutive years. Group 5 allergen was determined with a Phl p 5 specific ELISA in two fractions of ambient air: Particulate Matter (PM) >10μm and 10μm>PM>2.5μm. Mediator release by ambient air was determined in FcεR1-humanized basophils. Origin of pollen was modeled and condensed to pollen potency maps. Results: On average grass pollen released 2.3 pg Phl p 5/pollen. Allergen release per pollen (potency) varied substantially, ranging from 0 to 9 pg Phl p 5/pollen (5 to 95% percentile). The main variation was locally day-to-day. Average potency maps across Europe varied between years. Mediator release from basophilic granulocytes correlated better with allergen/m3 (r2=0.80, p<0.001) than with pollen/m3 (r2=0.61, p<0.001). In addition, pollen released different amounts of allergen in the nonpollen bearing fraction of ambient air depending on humidity. Conclusion: Across Europe, the same amount of pollen released substantially different amounts of group 5 grass pollen allergen. This variation in allergen release is on top of variations in pollen counts. Molecular aerobiology, i.e. determining allergen in ambient air, may be a valuable addition to pollen counting.

The fate of biologically produced methane in an anoxic fjord in British Columbia

Senior thesis written for Oceanography 445

Contributos para a compreensão do sucesso da cosmologia do big bang : uma análise themática à luz de Gerald Holton

Tese de doutoramento, História e Filosofia das Ciências, Universidade de Lisboa, Faculdade de Ciências, 2016

Spacing abstraction: capitalism, law and the metropolis

In considering contemporary accounts of the interrelations of economic, legal and urban forms of social relations in the emergence of a global capitalist modernity, this paper argues that politico-juridical imaginaries of new forms of transnational universality have tended to be limited by virtue of both an anachronistic recourse to spatial models of the polis and a failure to confront the ineliminability of abstraction to any idea of global social interconnectivity. In such terms, it argues, Lefebvre’s famous call for a ‘right to the city’ needs to be reinscribed as a properly modern right to the metropolis; one that would allow us to conceive of the possibility of new kinds of relation between individual and collective subjectivity and the development of abstract social forms.

The relationship between dimensions of love, personality, and relationship length

The present study examined the associations among participant demographics, personality factors, love dimensions, and relationship length. In total, 16,030 participants completed an internet survey assessing Big Five personality factors, Sternberg’s three love dimensions (intimacy, passion, and commitment), and the length of time that they had been involved in a relationship. Results of structural equation modeling (SEM) showed that participant age was negatively associated with passion and positively associated with intimacy and commitment. In addition, the Big Five factor of Agreeableness was positively associated with all three love dimensions, whereas Conscientiousness was positively associated with intimacy and commitment. Finally, passion was negatively associated with relationship length, whereas commitment was positively correlated with relationship length. SEM results further showed that there were minor differences in these associations for women and men. Given the large sample size, our results reflect stable associations between personality factors and love dimensions. The present results may have important implications for relationship and marital counseling. Limitations of this study and further implications are discussed.