Effective Theories for 2+1 Dimensional Non-Abelian Topological Spin Liquids

In this work we propose an effective low-energy theory for a large class of 2+1 dimensional non-Abelian topological spin liquids whose edge states are conformal degrees of freedom with central charges corresponding to the coset structure $su(2)_k\oplus su(2)_{k'}/su(2)_{k+k'}$. For particular values of $k'$ it furnishes the series for unitary minimal and superconformal models. These gapped phases were recently suggested to be obtained from an array of one-dimensional coupled quantum wires. In doing so we provide an explicit relationship between two distinct approaches: quantum wires and Chern-Simons bulk theory. We firstly make a direct connection between the interacting quantum wires and the corresponding conformal field theory at the edges, which turns out to be given in terms of chiral gauged WZW models. Relying on the bulk-edge correspondence we are able to construct the underlying non-Abelian Chern-Simons effective field theory.Comment: 41 pages, 5 figures, typos corrected, references added, published versio

How pervasive and mobile computing can help organizations to include people with visual disabilities on their client-approach strategy?

Organizations have in-built social responsibility to society. The evolution of technology have enable organizations to interact in an innovatively and more close approach to their clients. But this evolution has not included people with special needs like blind people. And, even those organizations that have enable some kind of support-approach to blind people, have typically disjointed, incomplete and typically parallel approaches; compared to their massclient standard approach. This paper discusses the potential of Pervasive and Mobile Computing to support, not just an innovative and unified approach, but also a real possibility of promoting real inclusion of blind people in what concerns to the delivery of information and services organizations offer. This paper also represents a reflection and a mind shaking attempt, while the authors are working in allowing blind people an autonomous buying process, in hypermarkets, supported by the use of wireless networks and modern mobile devices, with multiple technologies support, like Wi-Fi and inertial and magnetic sensors

Orientação de invisuais em espaços fechados combinando técnicas de multilateração, inerciais e magnéticas, usando redes 802.11 e dispositivos móveis

Tarefas como a deslocação em superfícies comerciais, para a aquisição de bens de consumo fazem parte da rotina diária da maioria dos cidadãos. Estas tarefas, simples e naturais para cidadãos sem deficiências, constituem-se numa barreira muito significativa, ou até uma impossibilidade, para cidadãos invisuais. Porém, no domínio das tecnologias de informação e comunicação, têm existido progressos na criação de novos mecanismos para auxiliar pessoas com necessidades especiais. Nomeadamente, a massificação das redes sem fios, os dispositivos móveis e os sistemas de apoio por voz, constituem recursos que potenciam significativos avanços para a integração plena dos cidadãos com deficiência visual nas actividades quotidianas das quais, actualmente, se encontram vedados. Neste artigo é apresentada uma arquitectura que combina dispositivos móveis e redes 802.11, que acreditamos possibilitar aos cidadãos invisuais a aquisição autónoma de bens de consumo em hipermercados

Exciton energies and wave functions in hexagonal Boron Nitride using Miller and Good’s uniform approach

In this paper we revisit the work of Miller and Good, which describes an uniform JWKB type of approximation to the solution of quantum problems. This paper, very well known in atomic physics in the 1970's 1980's of the last century, did not attract the same attention from the condensed matter community. Contrary to the usual JWKB approach, Miller and Good's method yields wave functions that do not diverge at the classical turning points. We apply the method in the context of two-dimensional excitons, an important condensed matter system. In particular, we apply our results to excitons in hexagonal boron nitride, solving the corresponding Wannier equation. We compare the semiclassical results with others from the literature and find good agreement.The authors acknowledge Mike Belsley for carefully reading the manuscript and for comments that allowed to improve the overall presentation. N.M.R.P. acknowledges support from the European Commission through the project "Graphene-Driven Revolutions in ICT and Beyond" (Ref. no. 881603 - core 3), and the Portuguese Foundation for Science and Technology (FCT) in the framework of the Strategic Financing UID/FIS/04650/2019. In addition, N.M.R.P. acknowledges COMPETE2020, PORTUGAL2020, FEDER and the Portuguese Foundation for Science and Technology (FCT) through projects POCI-01-0145-FEDER-028114, POCI-01-0145-FEDER- 029265, PTDC/NAN-OPT/29265/2017, and POCI-01-0145-FEDER-02888

Connecting school actors using mobile applications

Communication between the different actors present in the school ecosystem is an essential issue. However, in a busy world where parents do not have much time to visit schools regularly, it is crucial to create mechanisms to better monitor student success and school demands. The current pandemic situation caused by the coronavirus has highlighted the role that technologies have in supporting the mission of schools and communication between the various school actors. The interaction between school, students and parents presents a growing and complex challenge. Technology has, in recent years, shaped the concepts of support and monitoring of learning - at school and outside it - as well as the way in which information flows between all actors in the school ecosystem. Emergently, the evolution of mobile applications, combined with the evolution of the capabilities of mobile devices, has enabled the creation of new and more effective intercommunication mechanisms, with ubiquitous approaches and in a predictable scenario of less willingness for physical interaction of the different actors. Based on these premises, this article reflects on the potential of mobile devices and their applications to support new models of intercommunication between parents or school sponsors, students and teachers. In this sense, a conceptual model is proposed that represents a work in progress that aims at creating and evaluating a prototype system capable of improving intercommunication and the overall success of the societal challenges of the school learning system.UNIAG, R&D unit funded by the FCT – Portuguese Foundation for the Development of Science and Technology, Ministry of Science, Technology and Higher Education. UID/GES/4752/2019.info:eu-repo/semantics/publishedVersio

As Tecnologias de Informação e Comunicação nas licenciaturas de Turismo – a realidade em Portugal

Os desenvolvimentos ocorridos nos últimos anos nas Tecnologias de Informação e Comunicação motivaram inevitavelmente um grande efeito na operação, na estrutura e na estratégia das organizações, em todo o mundo, e, obviamente, também nas organizações do setor turístico. Através das Tecnologias de Informação e Comunicação, é possível reduzirem-se custos de comunicação e operacionalidade, podendo aumentarse a flexibilidade, a interatividade, a eficiência, a produtividade e a competitividade. As Tecnologias de Informação e Comunicação afiguram-se uma das áreas mais críticas para o sucesso do turismo no futuro e para a forma como se irá promover os destinos turísticos. Este artigo tem como objetivo analisar a relevância dada pelas diferentes instituições do ensino superior português às Tecnologias de Informação e Comunicação nas suas licenciaturas. A análise efetuada foi realizada em licenciaturas a funcionar no presente ano letivo, 2012/2013, em Institutos Politécnicos e Universidades Portuguesas, públicas e privadas

A cooperative agent-based security framework

The actual economic paradigm is based on a strongly cooperative model that tries to support a more competitive and global organizations response. With cooperation comes an intrinsic need - interconnection and interoperability of information systems among business partners. This represents, in many areas, a huge organizational challenge, being the field of information, and communication security one emerging key issue and a natural enabler for cooperative behavior and to the proper establishment and support of trust among network partners. Security frameworks, that can be able to describe and act on the basis of interoperability, cooperation and proactivity, became essential to support the new needs of modern business models. This paper present a framework that aims to contribute to a sustainable organizational information security-processes support, based on the ability to describe the allowed business process interactions among cooperative partners; furthermore, the framework presents a cooperative security perspective among partners basis on the idea that, if organizations have business cooperation, they should also have active security cooperation and regulation. If organizations, that need to cooperate, do not feel secure when they interconnect their information systems, the all cooperative perspective can fall down. Trust being one basic need for cooperation, impulse the need of a new security approach for cooperative scenarios

The information and communication technologies in tourism degree courses: the reality of Portugal and Spain

The developments occurring in recent years in the Information and Communication Technologies led inevitably to a great effect on the operation, structure and strategy of organizations around the world, and obviously also in the tourist sector organizations. With the rapid expansion of Information and Communication Technologies (ICT) throughout almost all aspects of tourism and hospitality industries, the task of integrating technology into education curriculum will be a need. Information and Communication Technologies appear one of the most critical area to the success of tourism in the future and the way it will promote the tourist destinations. This paper aims to analyze the relevance given by the various Portuguese and Spanish institutions of higher education to Information and Communication Technologies in their degrees. The analysis carried out was done in degree courses operating in this school year, 2012/2013, in Portuguese and Spanish universities and polytechnics, public and private