6,532 research outputs found
On the Lagrange and Markov Dynamical Spectra for Geodesic Flows in Surfaces with Negative Curvature
We consider the Lagrange and the Markov dynamical spectra associated to a
geodesic flow on a surface of negative curvature. We show that for a large set
of real functions on the unit tangent bundle and for typical metrics with
negative curvature and finite volume, both the Lagrange and the Markov
dynamical spectra have non-empty interior
Redundancy of classical and quantum correlations during decoherence
We analyze the time dependence of entanglement and total correlations between
a system and fractions of its environment in the course of decoherence. For the
quantum Brownian motion model we show that the entanglement and total
correlations have rather different dependence on the size of the environmental
fraction. Redundancy manifests differently in both types of correlations and
can be related with induced--classicality. To study this we introduce a new
measure of redundancy and compare it with the existing one.Comment: 6 pages, 4 figure
(Chloromethyl)pentacarbonylmanganese(I): a crystal structure with a non-crystallographic centre of symmetry
There are two molecules in the asymmetric unit of the P2â/c unit cell of ClCHâMn(CO)â
, the first halomethyl complex of manganese to be structurally determined. The molecules are crystallographically independent, despite an apparent local centre of symmetry. The average bond parameters include MnâCalkyl 2.128(8) Ă
, CâCl 1.811(8) Ă
and MnâCâCl 116.4(4)
Engineering context-aware systems and applications: a survey
Context-awareness is an essential component of systems developed in areas like Intelligent Environments, Pervasive & Ubiquitous Computing and Ambient Intelligence. In these emerging ïŹelds, there is a need for computerized systems to have a higher understanding of the situations in which to provide services or functionalities, to adapt accordingly. The literature shows that researchers modify existing engineering methods in order to better ïŹt the needs of context-aware computing. These efforts are typically disconnected from each other and generally focus on solving speciïŹc development issues. We encourage the creation of a more holistic and uniïŹed engineering process that is tailored for the demands of these systems. For this purpose, we study the state-of-the-art in the development of context-aware systems, focusing on: A) Methodologies for developing context-aware systems, analyzing the reasons behind their lack of adoption and features that the community wish they can use; B) Context aware system engineering challenges and techniques applied during the most common development stages; C) Context aware systems conceptualization
Context-awareness to increase inclusion of people with DS in society
Assistive technologies have the potential to enhance the quality of life of citizens. Most especially of interest are those cases where a person is affected by some physical or cognitive impairment. Whilst most work in this area have been focused on assisting people indoors to support their independence, the POSEIDON project is focused on empowering citizens with Downâs Syndrome to support their independence outdoors. This paper explains the POSEIDON module which we are in the process of developing to make the system context-aware,reactive and adaptive
ConcepçÔes de professores em formação em serviço sobre o ensino de ciĂȘncias nas sĂ©ries iniciais
Objetiva-se com este estudo analisar concepçÔes de professores das sĂ©ries iniciais do ensino fudamental sobre o ensino de CiĂȘncias e avaliar como um curso de formação em serviço incidiu sobre essas concepçÔes. Os sujeitos desta investigação sĂŁo 10 professores da regiĂŁo metropolitana de Campinas, SĂŁo Paulo, Brasil, que cursavam Licenciatura em Pedagogia. O curso continha uma disciplina sobre o ensino de CiĂȘncias. Ao inĂcio e ao final desta disciplina, foram coletadas concepçÔes dos professores cursantes atravĂ©s de questionĂĄrios. Concluiu-se que a maioria dos docentes pesquisados rejeitam visĂ”es ingĂȘnuas sobre o ensino de CiĂȘncias. Constatou-se ainda, que houve mudanças em relação as concepçÔes, apĂłs os professores cursarem a disciplina, principalmente no que se refere as idĂ©ias sobre as diferenças e semelhanças entre o senso comum e conhecimento cientĂfico
Sen, Sraffa and the revival of classical political economy
Copyright © 2012 Taylor & Francis.In his new book The Idea of Justice, Amartya Sen argues that political theory should not consist only in the characterisation of ideal situations of perfect justice. In so doing, Sen is making, within the context of political theory, a similar argument to another he also made in economic theory, when crtiticising what he called the ârational foolâ of mainstream economics. Sen criticised the ideal and fictitious agent of mainstream economics, while advocating for a return to an integrated view of ethics and economics, which characterised many classical political economists who inspired Sen's theory of justice, from Adam Smith to Karl Marx. I will examine Sen's revival of classical political economy, and argue that a revival of classical political economy, which was undertaken earlier by Piero Sraffa, has much potential for bringing a more plural and realist perspective to economics
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