System architecture for the ASBGo* Smart Walker

Dissertação de mestrado em Engenharia Eletrónica Industrial e ComputadoresWeakness, mobility and balance problems are some of the obstacles that most certainly will go along with the last period of life, the old age. Also, those difficulties can strike young lives due to gait abnormalities resulted from degenerative diseases or even accidents. To patients with high motor deficit, traditional methods, such as wheelchairs, are usually prescribed, but the use of an assistive device that do not promotes the patient’s recovery will eventually lead him to a restrict daily life as well as a notable loss of motor skills. With previous questions in mind, the Adaptive System Behavior Group (ASBG) decided to develop a motorized smart walker capable of adapting to the needs of its users. The Adaptive System Behavior Group Project (ASBGo) counts already with four versions that have proved its worth in clinical environment and was renowned, for two consecutive times, as one of the best technological and innovating Portuguese research projects in the rehabilitation field. However, the electromechanical and software solutions of each prototype commonly impair the global development of the project, making each version obsolete, outdated or unusable. Now, it is time to go further and render these proof-of-concept devices in a mature version, excluding previous academic solutions and engineering a robust and trustworthy device that will establish this new rehabilitation concept. This master thesis, addressed to rehabilitation robotics, describes the design and implementation of a system architecture for the Adaptive System Behavior Group Project Star (ASBGo*) . The implementation of a unified modular system architecture embraces the development of software components, electronic hardware and electromechanical modifications required to its implementation. This new prototype is an upgrade of the all ASBGo previous versions, in which the sturdy and user-friendly solutions implemented provide robust tools for future development and usability. Firstly, the contextualization in the project was performed, including a brief study of robotic software platforms, the familiarity with the several ASBGo prototypes and the research of the best solutions to design a system architecture. Secondly, following a Top-Down strategy, the work plan was established bearing in mind the considerations to design and implement a global system architecture: definition of the main functionalities and behaviours of the prototype and, simultaneously, the strategies to be followed in the hardware, electromechanical and software development. Hereinafter, the development stage was conducted following an Hardware-Software co-design methodology. That strategy ensured that the design and implementation of electronic and electric circuits were in agreement with all system requirements guaranteeing trade-offs, robustness and safety. During all the development process, validations of the system were constantly performed and, in the end, intensive experimentations of the final device were executed in the laboratory with the intervention of colleagues of the ASBG group.Debilidade e dificuldades de mobilidade e equilíbrio são alguns dos problemas que muito certamente irão acompanhar o período final da vida, a velhice. Para além disso, esses problemas podem atingir jovens vidas devido a anomalias na marcha resultantes de doenças degenerativas ou até mesmo acidentes. Aos pacientes que apresentam um alto défice motor, métodos tradicionais, como cadeiras de rodas, são normalmente receitados. No entanto, o uso de dispositivos de assistência que não promovem a recuperação do paciente irão eventualmente levá-lo a uma vida restrita assim como a uma notável perda de capacidades motoras. Com tal ideias em mente, o Adaptive System Behavior Group (ASBG) decidiu desenvolver um andarilho inteligente motorizado capaz de se adaptar as necessidades dos seus utilizadores. O Adaptive System Behavior Group Project (ASBGo) já conta com quatro versões que provaram o seu valor em ambiente clínico e já foi reconhecido, por duas vezes consecutivas, como um dos projetos de investigação mais tecnológico e inovador na área de reabilitação. Contudo, as soluções eletromecânicas e de software de cada protótipo comprometem o desenvolvimento contínuo do projeto, tornando cada versão obsoleta, desatualizada e inutilizável. Agora, está na hora de ir mais longe e tornar estes dispositivos de prova de conceito numa versão mais madura, excluindo as soluções académicas anteriormente implementadas e concebendo um dispositivo robusto e fiável que irá afirmar este novo conceito de reabilitação. A presente dissertação de mestrado, no âmbito da robótica de reabilitação, descreve o design e implementação de uma arquitetura de sistema para o Adaptive System Behavior Group Project Star (ASBGo*). A implementação de uma arquitetura de sistema unificada e modular envolve o desenvolvimento de componentes de software, hardware eletrónico e modificações eletromecânicas necessárias à sua implementação. Este novo protótipo consiste numa melhoria avançada de todas as versões anteriores do ASBGo no qual as soluções vigorosas e acessíveis implementadas providenciam meios para desenvolvimento futuro e usabilidade. Inicialmente, foi realizada a contextualização no projeto que incluiu uma breve pesquisa de plataformas de software robótico, a familiarização com os diferentes protótipos ASBGo e o estudo das melhores soluções para a conceção da arquitetura do sistema. Seguindo uma estratégia Top-Down, o plano de trabalhos foi estabelecido tendo em conta considerações para o design e implementação de uma arquitetura de sistema unificada: definição das principais funcionalidades e comportamentos do protótipo e, concomitantemente, as estratégias a ser seguidas no desenvolvimento eletromecânico, de hardware e de software. Doravante, a fase de desenvolvimento foi acompanhada por uma metodologia de Hardware-Software co-design. Esta estratégia assegurou a concordância entre o design e a implementação de circuitos eletrónicos e elétricos e todos os requisitos do sistema garantindo desta forma, trade-offs, robustez e segurança. Durante todo o processo de desenvolvimento, validações do sistema foram constantemente realizadas, sendo que no final testes intensivos ao produto final foram executados em laboratório com a intervenção dos colegas do grupo ASBG

Unfolding authenticity within retail gentrification in Mouraria, Lisbon

Retail gentrification is gaining relevance to study the transformation of several urban districts. In this article we explore the connections between this process and the appropriation and use of the elements of authenticity of a given urban district. Drawing upon the production standpoint, we based our research on the objective, constructivist and existential perspective of the concept of authenticity. We developed fieldwork on Mouraria, a traditional neighbourhood of Lisbon city centre, affected by gentrification as a consequence of a strong growth of tourism in the last decade. Information was collected about the size and evolution of the commercial fabric and business owners were interviewed. Its treatment allows to gather three set of elements that were considered as representative of the authenticity of Mouraria: community values, multiculturality and urban features. The way retail spaces use these elements is diverse and intertwined with the different perspectives of authenticity and, on the part of business owners, arises as a management practice. Although Mouraria can be currently placed within an early stage of retail gentrification, the current pace of retail change and gentrification occurring in the neighbourhood may led to a wider replacement of the commercial fabric with detrimental consequences for local residents.info:eu-repo/semantics/publishedVersio

Business Improvement Districts: A Systematic Review of an Urban Governance Model towards City Center Revitalization

For some time, business improvement districts (BIDs) have entered into the discourse and practice of academics and urban planners. This model for town centre revitalization was created in North America, whose success has led to its transfer to a growing number of countries. This evolution highlights the importance of BIDs as an urban planning practice, as well as an object of study for academics interested in new models for intervening in central urban areas. BIDs are public–private partnerships, framed within an entrepreneurial logic of urban management that aims to increase the cities’ competitiveness. In this article, we aim to unfold the main research subjects of the literature focused on BIDs. We develop a systematic review for said endeavor, resorting to the established PRISMA protocol. After the screening and analysis of selected articles, four main research subjects were documented: (i) urban governance; (ii) urban policies: mobility and transfer; (iii) activities/axis of intervention; and (iv) types of BIDs/places of intervention. The selected literature enhances the contradictory nature of BIDs, ranging from the economic revitalization of city centres to the occasional exclusionary stance, in which it is developed. Our analysis also points to the important role of different actors in all stages of the policy transfer and implementation.info:eu-repo/semantics/publishedVersio

U.S. Unemployment Duration: Has Long Become Longer or Short Become Shorter?

The U.S. labor market has been experiencing unprecedented high average unemployment duration. The shift in the unemployment duration distribution can be traced back to the early nineties. In this study, censored quantile regression methods are employed to analyze the changes in the US unemployment duration distribution. We explore the decomposition method proposed by Machado and Mata (2005) to disentangle the contribution of the changes generated by the covariate distribution and by the conditional distribution. The data used in this inquiry are taken from the nationally representative Displaced Worker Surveys of 1988 and 1998. We provide evidence that the change in the unemployment duration distribution is mainly produced by the opposing effects of a sharp rise in job-to-job transition rates and an increased sensitivity of unemployment duration to unemployment rates. Compositional changes in the labor force played a limited role. We rationalize our findings by arguing that improved screening technology is likely to be the relevant underlying mechanism at work.

Energy efficient scheme based on simultaneous transmission of the local decisions in cooperative spectrum sensing

A common concern regarding cooperative spectrum sensing (CSS) schemes is the occupied bandwidth and the energy consumption during the transmissions of sensing information to the fusion center over the reporting control channels. This concern is intensified if the number of cooperating secondary users in the network is large. This article presents a new fusion strategy for a CSS scheme, aiming at increasing the energy efficiency of a recently proposed bandwidth-efficient fusion scheme. Analytical results and computational simulations unveil a high increase in energy efficiency when compared with the original approach, yet achieving better performances in some situations, and lower implementation complexity

Tourism and Authenticity: Analyzing Retail Change in Lisbon City Center

Retail is one of the defining elements of urban spaces. The study of commerce is largely based on its evolution and how it relates with urban environments. Currently, with the advent of mass tourism, there has been an adjustment in the commercial fabric of the area’s most sought after by tourists. Among these latter areas, the historical centers of commerce stand out. The first objective of this research is to analyze the modern evolution of the commercial fabric of Lisbon by comparing the city center with the rest of the city. For this goal, I use a quantitative approach through the quotient location for specific retail typologies. The results show dissimilarities that are associated with the geographical location of retail, which vary according to the different retail typologies being analyzed. The second goal is based on the assumption that the mere analysis of the evolution of the retail typologies is limited in the context of tourist cities. Considering this matter, a qualitative method (photo analysis, conceptually supported by the concept of authenticity) is used. The results show the usefulness of the concept of authenticity to apprehend and discuss how retail is reacting to the tourism industry, thereby contributing to the transformation of the city center into a leisure and entertainment destination.info:eu-repo/semantics/publishedVersio

Perfil dos observadores de aves no Parque Natural da Ria Formosa

In the Algarve the potential for birdwatching tourism is widely recognized, especially in the Ria Formosa Natural Park (RFNP). This study aims to describe birdwatchers' profile in the RFNP. For this purpose, a survey was applied. The results show that the most frequent nationalities of birdwatchers are: British (39%), Dutch (17%) and Portuguese (17%). The majority of birdwatchers are male (55%) and married (57%). The average age is 50 years old. They are highly educated (74% have an academic degree). Concerning profession, the most frequent answer was retired (41%). Respondents are committed to the activity as the majority possess special equipment and practice birdwatching in vacations. This study also tests if nationality is related to other characteristics of the birdwatchers, by using the Kruskal-Wallis and the Chi-square tests. Overall, the results of this study highlight that regional management organizations should invest in developing birdwatching in the RFNP.O potencial para o turismo de birdwatching é vastamente reconhecido, especialmente no Parque Natural da Ria Formosa (PNRF). Este estudo tem como objetivo descrever o perfil dos observadores de aves que visitam o PNRF. Para esse propósito, foi aplicado um questionário. Os resultados mostram que as nacionalidades mais frequentes dos observadores de aves são: britânica (39%), holandesa (17%) e portuguesa (17%). A maioria dos observadores de aves é do sexo masculino (55%), sendo o seu estado civil casado (57%). A idade média é de 50 anos. O seu nível educacional é elevado (74% têm um grau académico). Quanto à profissão, a resposta mais frequente foi aposentado (41%). Os inquiridos estão comprometidos com a atividade, pois a maioria possui equipamentos especiais e pratica observação de aves nas férias. Este estudo também testa se a nacionalidade está relacionada com outras características dos observadores de aves, através de testes Kruskal-Wallis e Qui-quadrado. Os resultados deste estudo indicam que as organizações de gestão regional devem investir no desenvolvimento do birdwatching no PNRF.info:eu-repo/semantics/publishedVersio