Music, sounds, the Stradivarius and the computer: A dialogue between the music-maker and the music-listener

In what might be described as an 'ecological' spirit, here I recycle an ancient form, the dialogue. I find the dialogue form particularly appealing for its potential to encapsulate ideas both as content and form. This dialogue, between the music-maker and music-listener, is intended as an allegory that uses accessible language in a contemporary, conversational style. From an epistemological perspective, the split maker-listener may be viewed as a fabrication that subsumes numerous conflicts at personal, group and societal levels. The text is about creativity, freedom and ownership, about concept, percept and practice within multidisciplinary and multicultural contexts. It can be reconstructed in different ways when the music-maker and the music-listener are personified under a multitude of guises within multiple contexts. I have added a bibliographic list following the dialogue that includes some examples of the background reading that has helped to shape the thinking underlying the text. In particular, I have been deeply influenced by Gregory Bateson's writings, especially his 'metalogues', a collection of humorous, deceptively light dialogues that do not specify theatrical elements. I feel this lack of obvious affective content in the text allows readers to construe their own views of how the negotiation of discourses may take place, regardless of what I may have imagined or thought to have implied – or not – using a few italicised words

Deductive Verification of Parallel Programs Using Why3

The Message Passing Interface specification (MPI) defines a portable message-passing API used to program parallel computers. MPI programs manifest a number of challenges on what concerns correctness: sent and expected values in communications may not match, resulting in incorrect computations possibly leading to crashes; and programs may deadlock resulting in wasted resources. Existing tools are not completely satisfactory: model-checking does not scale with the number of processes; testing techniques wastes resources and are highly dependent on the quality of the test set. As an alternative, we present a prototype for a type-based approach to programming and verifying MPI like programs against protocols. Protocols are written in a dependent type language designed so as to capture the most common primitives in MPI, incorporating, in addition, a form of primitive recursion and collective choice. Protocols are then translated into Why3, a deductive software verification tool. Source code, in turn, is written in WhyML, the language of the Why3 platform, and checked against the protocol. Programs that pass verification are guaranteed to be communication safe and free from deadlocks. We verified several parallel programs from textbooks using our approach, and report on the outcome.Comment: In Proceedings ICE 2015, arXiv:1508.0459

Divide and conquer: resonance induced by competitive interactions

We study an Ising model in a network with disorder induced by the presence of both attractive and repulsive links. This system is subjected to a subthreshold signal, and the goal is to see how the response is enhanced for a given fraction of repulsive links. This can model a network of spin-like neurons with excitatory and inhibitory couplings. By means of numerical simulations and analytical calculations we find that there is an optimal probability, such that the coherent response is maximal

Spectroscopic direct detection of reflected light from extra-solar planets

At optical wavelengths, an exoplanet's signature is essentially reflected light from the host star - several orders of magnitude fainter. Since it is superimposed on the star spectrum its detection has been a difficult observational challenge. However, the development of a new generation of instruments like ESPRESSO and next generation telescopes like the E-ELT put us in a privileged position to detect these planets' reflected light as we will have access to extremely high signal-to-noise ratio spectra. With this work, we propose an alternative approach for the direct detection of the reflected light of an exoplanet. We simulated observations with ESPRESSO@VLT and HIRES@E-ELT of several star+planet systems, encompassing 10h of the most favourable orbital phases. To the simulated spectra we applied the Cross Correlation Function to operate in a much higher signal-to-noise ratio domain than when compared with the spectra. The use of the Cross-Correlation Function permitted us to recover the simulated the planet signals at a level above 3 \sigma_{noise} significance on several prototypical (e.g., Neptune type planet with a 2 days orbit with the VLT at 4.4 \sigma_{noise} significance) and real planetary systems (e.g., 55 Cnc e with the E-ELT at 4.9 \sigma_{noise} significance). Even by using a more pessimistic approach to the noise level estimation, where systematics in the spectra increase the noise 2-3 times, the detection of the reflected light from large close-orbit planets is possible. We have also shown that this kind of study is currently within reach of current instruments and telescopes (e.g., 51 Peg b with the VLT at 5.2 \sigma_{noise} significance), although at the limit of their capabilities.Comment: Accepted for Publication on MNRAS: 2013 August 29; Online Article: http://mnras.oxfordjournals.org/content/early/2013/09/27/mnras.stt1642; 5 Figures, 11 page

Estão os portugueses preparados para o futuro do turismo? Aplicação do modelo de aceitação tecnológica ao uso de robots em turismo

The tourism sector has been growing exponentially in Portugal over the last few years, becoming increasingly competitive. On the other hand, the use of machines, robots and artificial intelligence in this industry that is built by and for people, has also been increasing and diversifying. The objective of this investigation focuses on the study of variables that can affect the acceptance of robots by the Portuguese public. The Technology Acceptance Model (TAM) is applied to understand the influence of a set of sociodemographic variables, travel behavior, motivation, and attitude towards technology in general in the perceived ease of use and perceived usefulness of using robots in tourism. The results obtained demonstrate that the Portuguese case is similar to that of other Western countries, with gender, age, travel group, motivation and attitude towards technology having a significant impact on the dependent variables.O setor do turismo em Portugal tem vindo a crescer exponencialmente nos últimos anos, tornando-se cada vez mais competitivo. Por outro lado, o uso de máquinas, robots e inteligência artificial nesta que é uma indústria construída por e para pessoas, tem também vindo a aumentar e a diversificar-se. O objetivo desta investigação centra-se no estudo das variáveis que podem afetar a aceitação dos robots por parte do público português. É aplicado o Modelo de Aceitação Tecnológica para perceber a influência de um conjunto de variáveis sociodemográficas, de comportamento em viagem, de motivação e de atitude face à tecnologia em geral na facilidade de utilização percebida e utilidade percebida do uso de robots em turismo. Os resultados obtidos permitem concluir que o caso português se assemelha ao de outros países ocidentais, tendo o género, idade, grupo de viagem, motivação e atitude face à tecnologia um impacto significativo nas variáveis dependentes.Mestrado em Gestão e Planeamento em Turism

Biometric recognition based on the texture along palmprint lines

Tese de Mestrado Integrado. Bioengenharia. Faculdade de Engenharia. Universidade do Porto. 201

K X-Ray Energies and Transition Probabilities for He-, Li- and Be-like Praseodymium ions

Theoretical transition energies and probabilities for He-, Li- and Be-like Praseodymium ions are calculated in the framework of the multi-configuration Dirac-Fock method (MCDF), including QED corrections. These calculated values are compared to recent experimental data obtained in the Livermore SuperEBIT electron beam ion trap facility

Status and conspicuousness on sustainable fashion products : examining the role of conspicuousness between status motives and consumers’ sustainable fashion valuations

The fashion industry is believed to be the second­-largest polluting industry worldwide. Hence, understanding the underlying reasons motivating socially and environmentally responsible consumption behaviors is crucial to implement the necessary changes in this industry. The present dissertation aims to examine the effect of social motivations, such as activating status motives, on consumers’ attitudes and perceptions towards sustainable fashion products. Based on an academic literature review regarding sustainable fashion, conspicuousness and status consumption, an experimental design study was conducted. The purpose was to examine the impact of status and prestige motivations on consumers’ sustainable fashion valuations, such as purchasing behaviors, product, and brand perceptions. Results show that activating status motives enhance status and prestige motivations. In turn, conspicuously signaling a sustainable fashion product moderates the effect that status and prestige motivations have on consumers’ valuations. Findings show that a desire for status is capable of inciting self­-sacrifice and consequently motivating sustainable consumption decisions. Additionally, brand iconicity perceptions indirectly explain the process through which conspicuous consumption orientation impacts sustainable fashion valuations. Therefore, consumers tend to use the symbolic value of iconic brands to express their social identity and communicate their desires and aspirations with others. This study provides valuable consumer behavior insights, suggesting brands’ approach to sustainability should not disregard society’s predisposition for consumption. Forthwith, researchers, managers, and marketers trying to incite sustainable consumption might obtain more effective and long-­lasting results if they factor in individual traits and predispositions since these are able to influence consumption behavioral patterns within the fashion context.A indústria da moda é considerada a segunda maior indústria poluidora do mundo. Assim sendo, é fundamental compreender as razões que motivam os comportamentos social e ambientalmente responsáveis para implementar as mudanças necessárias nesta indústria. A presente dissertação tem como objetivo examinar o efeito de motivações sociais nas preferências e perceções dos consumidores em relação a produtos sustentáveis. Com base em literatura académica sobre moda sustentável, consumo conspícuo e status, foi realizado um estudo experimental para testar o impacto das motivações por status nas atitudes e perceções dos consumidores, em relação a produtos de moda sustentáveis. Os resultados mostram que, altos níveis de conspicuidade em produtos de moda sustentáveis, impactam positivamente o efeito que motivações por status têm nas atitudes e perceções dos consumidores. Tal efeito resulta de as motivações por status serem capazes de incitar altruísmo e motivar comportamentos pró­sociais e ambientais. Adicionalmente, as perceções de iconicidade do consumidor sobre o produto, relacionam a orientação de consumo conspícuo do consumidor com os comportamentos e perceções de consumo sustentável, uma vez que os consumidores tendem a usar o valor simbólico de marcas icónicas para expressar a sua identidade social e comunicar as suas ambições. Concluindo, este estudo fornece conhecimento sobre o comportamento do consumidor, sugerindo que a abordagem das marcas à sustentabilidade não deve desconsiderar a predisposição da sociedade para o consumo. Deste modo, profissionais que procurem incentivar consumo sustentável, poderão obter resultados mais eficazes e duradouros se considerarem características e predisposições individuais capazes de influenciar os padrões de consumo