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Publications

2018

Evaluation of SAR induced by a Planar Inverted-F Antenna based on a Realistic Human Model

Authors
Vieira, VF; Pessoa, LM; Carvalho, MI;

Publication
EMBEC & NBC 2017

Abstract
In this paper the absorption by the human body of electromagnetic (EM) radiation generated by a Planar Inverted-F Antenna (PIFA) from a modern mobile phone is investigated through the evaluation of the Specific Absorption Rate (SAR) in head, brain and hand regions using Sim4Life (S4L) and a realistic anatomical model. Several scenarios were evaluated, by varying the distance between the antenna and the head, the feeder position and the orientation of the antenna. The effect of the presence of the hand was also studied and, finally, different communication bands were considered. The main results show that the presence of the hand is determinant to reduce SAR on head and brain, while bottom orientations of the antenna reduce the SAR on the brain, but increase the SAR in other tissues.

2018

Multi-Agent Decision Support Tool to Enable Interoperability among Heterogeneous Energy Systems

Authors
Teixeira, B; Pinto, T; Silva, F; Santos, G; Praca, I; Vale, Z;

Publication
APPLIED SCIENCES-BASEL

Abstract
Worldwide electricity markets are undergoing a major restructuring process. One of the main reasons for the ongoing changes is to enable the adaptation of current market models to the new paradigm that arises from the large-scale integration of distributed generation sources. In order to deal with the unpredictability caused by the intermittent nature of the distributed generation and the large number of variables that contribute to the energy sector balance, it is extremely important to use simulation systems that are capable of dealing with the required complexity. This paper presents the Tools Control Center (TOOCC), a framework that allows the interoperability between heterogeneous energy and power simulation systems through the use of ontologies, allowing the simulation of scenarios with a high degree of complexity, through the cooperation of the individual capacities of each system. A case study based on real data is presented in order to demonstrate the interoperability capabilities of TOOCC. The simulation considers the energy management of a microgrid of a real university campus, from the perspective of the network manager and also of its consumers/producers, in a projection for a typical day of the winter of 2050.

2018

SOURCE SEPARATION IN THE PRESENCE OF SIDE INFORMATION: NECESSARY AND SUFFICIENT CONDITIONS FOR RELIABLE DE-MIXING

Authors
Sabetsarvestani, Z; Renna, F; Kiraly, F; Rodrigues, MRD;

Publication
2018 IEEE GLOBAL CONFERENCE ON SIGNAL AND INFORMATION PROCESSING (GLOBALSIP 2018)

Abstract
This paper puts forth new recovery guarantees for the source separation problem in the presence of side information, where one observes the linear superposition of two source signals plus two additional signals that are correlated with the mixed ones. By positing that the individual components of the mixed signals as well as the corresponding side information signals follow a joint Gaussian mixture model, we characterise necessary and sufficient conditions for reliable separation in the asymptotic regime of low-noise as a function of the geometry of the underlying signals and their interaction. In particular, we show that if the subspaces spanned by the innovation components of the source signals with respect to the side information signals have zero intersection, provided that we observe a certain number of measurements from the mixture, then we can reliably separate the sources, otherwise we cannot. We also provide a number of numerical results on synthetic data that validate our theoretical findings.

2018

A generative model for the characterization of musical rhythms

Authors
Sioros, G; Davies, MEP; Guedes, C;

Publication
JOURNAL OF NEW MUSIC RESEARCH

Abstract
We present a novel model for the characterization of musical rhythms that is based on the pervasive rhythmic phenomenon of syncopation. Syncopation is felt when the sensation of the regular beat or pulse in the music is momentarily disrupted; the feeling arises from breaking more expected patterns such as pickups (anacrusis) and faster events that introduce and bridge the notes articulated on the beats. Our model begins with a simple pattern that articulates a beat consistent with the metrical expectations of a listener. Any rhythm is then generated from a unique combination of transformations applied on that simple pattern. Each transformation introduces notes in off-beat positions as one of three basic characteristic elements: (1) syncopations, (2) pickup rhythmic figures and (3) faster notes that articulate a subdivision of the beat. The characterization of a pattern is based on an algorithm that discovers and reverses the transformations in a stepwise manner. We formalize the above transformations and present the characterization algorithm, and then demonstrate and discuss the model through the analysis of the main rhythmic pattern of the song Don't stop till you get enough' by Michael Jackson.

2018

Exploring Customers’ Internal Response to the Service Experience: An Empirical Study in Healthcare

Authors
Beirão, G; Costa, H;

Publication
Lecture Notes in Business Information Processing

Abstract
Service organizations increasingly understand the importance of managing the customer experience to enhance customer satisfaction and loyalty. This study aims to develop a better understanding of the customer experience by investigating how the customer’s internal mechanisms influence it. That is, how it is perceived and processed at three different levels (visceral, behavioral and reflective), which determines a person’s cognitive and emotional state. To this purpose an exploratory multi-method ethnographic study was undertaken in a healthcare service. The results showed the emotions provoked by the service experience at each level. These levels are interconnected and impact each other working together to influence a person’s cognitive and emotional state, and thus playing a critical role in the overall evaluation of a service. Results show that elements such as servicescape aesthetics, face-to-face and non-human interactions influence emotions and service evaluations. The service should be designed in a way that induces positive emotions, and a feeling of being in control. Especially in healthcare services there is a need to balance the conflicting responses of the emotional stages that may be triggered at the visceral and behavioral levels, while providing reassurance and calm at the reflective level that the health problem is going to be taken care. Using service design approaches this understanding of the customers’ brain can be translated into improving the customer experience. © 2018, Springer Nature Switzerland AG.

2018

Marketing and Technologies Platforms in Smart F-Store

Authors
Santos, JD; Almeida, FL;

Publication
Advances in Human Resources Management and Organizational Development - Managing Diversity, Innovation, and Infrastructure in Digital Business

Abstract
Social networks, originally built as channels for personal interaction, are being used in the commercial market as a support for product sales. The use of applications integrated in social networks appears as an opportunity to explore by companies. Facestore emerged in 2013 as the first e-commerce solution integrated in social networks, allowing the creation of online stores within Facebook, without the customer having to leave the social network interface. Operations like looking into the catalog, choosing the product, and paying the transaction is carried out without the customer need to open a new website. The use of Facestore offers direct and indirect benefits on the different areas of an organization. At the direct level, there are changes in processes in terms of customer service and marketing and sales. However, its use also potentiates indirect benefits in other organizational areas, such as operations, finance, administration and information technologies support, human resources, and research and development.

  • 2008
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