102 research outputs found
A buil-in mixed-signal block observer (BIMBO) to improve observability in 1149.4 environments
This document proposes an extension to the IEEE 1149.4 test infrastructure, whereby a bank of sigma-delta first order modulators enables the simultaneous observation of several analog pins in a single component. The modulator output bit streams are shifted out and made available to an external test controller that comprises the corresponding bank of decimation filters and other decision and control logic. The architecture proposed is fully non-intrusive and may be used to support debug and test operations in mixed-signal environments
Weighing-in-motion wireless system for sustainable railway transport
Railway transport is well known as one of the safest and most energy-efficient transport modes, thus favoring its strengthening as part of a sustainable transport system. Yet, the track service life and the quality of the ride on a railway are dependent upon different factors, which can be assessed by a diverse set of technology based systems. In this context, this paper presents the EVO4Rail project that seeks to design, develop and implement a wireless monitoring system for weighing-in-motion and detecting faulty wheels in railway vehicles, positively impacting railway operation, maintenance and management, ultimately aiming at a sustainable rail transport.info:eu-repo/semantics/publishedVersio
Molecular evidence for gender differences in the migratory behaviour of a small seabird
Molecular sexing revealed an unexpectedly strong female bias in the sex ratio of pre-breeding European Storm Petrels (Hydrobates pelagicus), attracted to playback of conspecific calls during their northwards migration past SW Europe. This bias was consistent across seven years, ranging from 80.8% to 89.7% female (mean annual sex ratio ± SD = 85.5% female ±4.1%). The sex ratio did not differ significantly from unity (i.e., 50% female) among (i) Storm Petrel chicks at a breeding colony in NW France, (ii) adults found dead on beaches in Southern Portugal, (iii) breeding birds attending nest burrows in the UK, captured by hand, and (iv) adults captured near a breeding colony in the UK using copies of the same sound recordings as used in Southern Europe, indicating that females are not inherently more strongly attracted to playback calls than males. A morphological discriminant function analysis failed to provide a good separation of the sexes, showing the importance of molecular sexing for this species. We found no sex difference in the seasonal or nocturnal timing of migration past Southern Europe, but there was a significant tendency for birds to be caught in sex-specific aggregations. The preponderance of females captured in Southern Europe suggests that the sexes may differ in migration route or in their colony-prospecting behaviour during migration, at sites far away from their natal colonies. Such differences in migration behaviour between males and females are poorly understood but have implications for the vulnerability of seabirds to pollution and environmental change at sea during the non-breeding season
Debugging mixed-signals circuits via IEEE1149.4 – a built-in mixed condition detector
Diagnosing design faults in a mixed-signals circuit is no
trivial task, due to the inherent uncertainties associated
with analog signals, not mentioning the interaction
between the analog part and the digital part. Using debug
and test tools is one way to deal with the problem,
especially during the prototyping phase, however if a
physical access is required then the same restrictions that
led to other solutions, based on electronic access, apply.
This is particularly the case that led to the emergence and
wide acceptance of the IEEE1149 family of test
infrastructures, which relies on an electronic test access
port. While the IEEE1149.4 test infrastructure enables the
structural and parametric test of mixed-signal boards, its
use is still far from reaching a wide acceptance, namely
due to the lack of alternative applications, such as
debugging, as seen in the 1149.1 domain of purely digital
circuits. Building upon the rationale that enabled
transferring the structural test of board interconnections
between analog pins, from the analog domain to the
digital domain, using the mechanisms present in an
Analog Boundary Module, as defined in the IEEE1149.4
Std., we propose a new way to support debug operations
in 1149.4 mixed-signals circuits. In particular, we
describe a built-in mechanism able to detect both internal
and pin-level mixed-signal conditions, and hence able to
support watchpoint/breakpoint operations at the IC level.info:eu-repo/semantics/publishedVersio
The VISIR+ Project – Helping Contextualize Math in an Engineering Course
[EN]The long-term goal of engineering education is to prepare students to work as engineers. Being a practical profession, laboratories play a crucial role in illustrating concepts and principles as well as improving technical skills. In the last decades the use of online resources (simulators and remote labs) has been growing, either as a complementary and/or as an alternative way of developing experimental competences. In the scope of the VISIR+ Project, this work presents the first results of a didactical implementation using simultaneously the remote laboratory VISIR (Virtual Instrument Systems in Reality), simulation and calculus in a Math Course at the Federal University of Santa Catarina (UFSC). The preliminary results indicate that the use of several resources increases students’ performance, boosting their learning and competence development
Evaluating COVID-19 in Portugal: Bootstrap confidence interval
In this paper, we consider a compartmental model to fit the real data of confirmed active cases with COVID-19 in Portugal, from March 2, 2020 until September 10, 2021 in the Primary Care Cluster in Aveiro region, ACES BV, reported to the Public Health Unit. The model includes a deterministic component based on ordinary differential equations and a stochastic component based on bootstrap methods in regression. The main goal of this work is to take into account the variability underlying the data set and analyse the estimation accuracy of the model using a residual bootstrapped approach in order to compute confidence intervals for the prediction of COVID-19 confirmed active cases. All numerical simulations are performed in R environment ( version. 4.0.5). The proposed algorithm can be used, after a suitable adaptation, in other communicable diseases and outbreaks
Data mining techniques for the grouping of certified wines from the sub-regions of the demarcated region of Vinho Verde
The combination of information obtained from data mining technique from physicochemical and organoleptic data analysis allowed similarities between the wines of the nine sub-regions in the Demarcated Region of Vinho Verde. Through clustering techniques, four clusters were identified, each characterized by its centroid. The measure of information gain, together with supervised rule-based learning, was used to find the differentiating characteristics. This study allowed the interconnection of the characteristics of the wines of these sub-regions, which can improve the decision making on the profiles of these same wines
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