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Publications

2018

Optical coherence tomography within a single microsystem

Authors
Maciel, MJ; Rosa, CC; Wolffenbuttell, RF; Correia, JH;

Publication
JOURNAL OF PHYSICS D-APPLIED PHYSICS

Abstract
Optical coherence tomography (OCT) systems have huge potential for applications beyond the traditional ophthalmology as a general-purpose medical instrument for optical biopsy. The widening of the range of applications is expected to significantly increase production volume and, consequently, puts pressure on unit cost. This trend calls for a flexible and miniaturized system fabricated in a batch process. In this paper, the different OCT configurations are compared for suitability in such an implementation. The required flexibility favors operation in the spectral domain, using a broadband light source in combination with a spectrometer, while the miniaturization and low unit-cost in batch fabrication can be achieved using silicon micro-system technologies. The feasibility of miniaturizing OCT components has already been demonstrated, amongst others a beam splitter using 45 degrees saw dicing of a glass substrate and appropriate thin-film coating the integration of the essential components into a single OCT microsystem remains a challenge. In this paper, the wafer-level fabrication of a Michelson interferometer for a miniaturized OCT system is presented, using an improved 45 degrees saw dicing process, which is suitable for wafer-level co-integration of also the other components of the OCT microsystem.

2018

On the Interoperability of European National Identity Cards

Authors
Shehu, AS; Pinto, A; Correia, ME;

Publication
ISAmI

Abstract
Electronic identity (eID) schemes are key enablers of secure digital services. eIDs have been adopted in several European countries using smart-cards for secure authentication and authorization. Towards achieving a European digital single market where European citizens can seamlessly access cross-border public services using their national eIDs, the European Union (EU) developed the electronic IDentification, Authentication and trust Services (eIDAS) regulation. eIDAS creates an interoperable framework that integrates the eIDs adopted in the EU Member States (MS). It is also an enabler of a cross-border operation, harmonized with the General Data Protection Regulation (GDPR) regulation by protecting the privacy of personal data. If one can use the same procedure for authentication and authorization abroad, one can better understand new services that use eIDs. This paper provides a comparative analysis of eID cards adopted in EU MS and their privacy features in preparedness for eIDs cross-border interoperation.

2018

Heart Rate, Electrodermic Activity and Self-Reported Experience in Shooter Games, in University Students

Authors
Vasconcelos-Raposo, J; Universidade de Trás-os-Montes e Alto Douro, Vila Real, Portugal.,; Fernandes, J; Nobre, S; Teixeira, S;

Publication
PSYCHTECH & HEALTH JOURNAL

Abstract

2018

Developing a Geologically Based VS30 Site-Condition Model for Portugal: Methodology and Assessment of the Performance of Proxies

Authors
Vilanova, SP; Narciso, J; Carvalho, JP; Lopes, I; Quinta Ferreira, M; Pinto, CC; Moura, R; Borges, J; Nemser, ES;

Publication
BULLETIN OF THE SEISMOLOGICAL SOCIETY OF AMERICA

Abstract
The inclusion of site-specific conditions is essential to adequately represent the seismic hazard and the seismic risk for a region. We acquired, gathered, and organized a near-surface shear-wave velocity database for Portugal and applied a three-step methodological approach for developing a V-S30 site-condition map using extrapolation based on surface geology. The methodology includes (1) defining a preliminary set of geologically defined units, (2) calculating the probability distribution of log V-S30 for each unit, and (3) merging the units according to the results of statistical tests. The final model comprises three geologically defined units characterized by log V-S30 distributions that are statistically significantly different from each other: F1, igneous, metamorphic, and old sedimentary rocks; F2, Neogene and Pleistocene formations; and F3, Holocene formations. The site conditions for the F3 unit may be further refined using correlations with topographic slope based on the Shuttle Radar Topography Mission at 3 arcsec resolution (SRTM3) dataset. We analyzed the performance site-condition models based on correlations with exogenous data (topographic slope and surface-geology analogs). The results show that the residual distributions between log V-S30 values measured and estimated from those proxies are strongly biased for some geological units, emphasizing the need for acquiring regional V-S data.

2018

Tone Mapping HDR Panoramas for Viewing in Head Mounted Displays

Authors
Melo, M; Bouatouch, K; Bessa, M; Coelho, H; Cozot, R; Chalmers, A;

Publication
VISIGRAPP (1: GRAPP)

Abstract
Head-mounted displays enable a user to view a complete environment as if he/she was there; providing an immersive experience. However, the lighting in a full environment can vary significantly. Panoramic images captured with conventional, Low Dynamic Range (LDR), imaging of scenes with a large range of lighting conditions, can include areas of under- or over-exposed pixels. High Dynamic Range (HDR) imaging, on the other hand, is able to capture the full range of detail in a scene. However, HMDs are not currently HDR and thus the HDR panorama needs to be tone mapped before it can be displayed on the LDR HMD. While a large number of tone mapping operators have been proposed in the last 25 years, these were not designed for panoramic images, or for use with HMDs. This paper undertakes a two part subjective study to investigate which of the current, state-of-the-art tone mappers is most suitable for use with HMDs.

2018

ORSUM Chairs' Welcome & Organization

Authors
Jorge, A; Vinagre, J; Matuszyk, P; Spiliopoulou, M;

Publication
WWW (Companion Volume)

Abstract

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