INESC-ID

About: INESC-ID is a nonprofit organization based out in Lisbon, Portugal. It is known for research contribution in the topics: Computer science & Context (language use). The organization has 932 authors who have published 2618 publications receiving 37658 citations.

EC/NSF workshop on universal accessibility of ubiquitous computing: providing for the elderly event report

Abstract: The workshop took place on Alcacer do Sal, Portugal from May 22nd to May 25th, 2001 with the purpose to discuss approaches to universal usability for the elderly constituency Elderly citizens are a growing age group within developed countries and their needs have been mostly ignored by Information Technology and Computing as a whole The surge of mobile communications and universal access materialized in the push for UMTS in Europe provided a strong leitmotif for this meeting For the better part of a week, a group joining twenty-six people from several different communities gathered to discuss strategic issues arising from the new context The aim is to provide strategic inputs for major research programs in EU, USA and Japan The present document contains a summary account of the proceedings

Dealing With Unknown Impedance and Impulsive Noise in the Power-Line Communications Channel

Abstract: Power-line communication (PLC) allows establishing digital communications without adding any new wires. It will turn one's house or neighborhood grid into a smart grid. PLC has some issues, namely, high noise at low frequencies and varying characteristic impedance. This paper addresses these issues to improve the signal-to-noise ratio by increasing the signal or reducing the noise. PLC MODEMs are subject to legislations that limit the signals in the line. The radiated signal is proportional to the current, but not to the input current, since the current forms a standing wave along the line. However, better performance can be achieved if the input current is measured. The receiver circuit of the transmitting MODEM can be used to estimate the input impedance. This paper presents a technique to use this new information to achieve better performance and to follow legislation changes in the band above 30 MHz. A study of the viability of using impulsive noise reduction techniques to further increase performance is also presented. The short noise pulses result in high correlation between the noises in different carriers. Impulse position detection should result in an increase in capacity.

Clear-PEM: A PET imaging system dedicated to breast cancer diagnostics

Abstract: The Clear-PEM scanner for positron emission mammography under development is described. The detector is based on pixelized LYSO crystals optically coupled to avalanche photodiodes and readout by a fast low-noise electronic system. A dedicated digital trigger (TGR) and data acquisition (DAQ) system is used for on-line selection of coincidence events with high efficiency, large bandwidth and small dead-time. A specialized gantry allows to perform exams of the breast and of the axilla. In this paper we present results of the measurement of detector modules that integrate the system under construction as well as the imaging performance estimated from Monte Carlo simulated data.

An FPGA Implementation for a Kalman Filter with Application to Mobile Robotics

Abstract: The problem of simultaneous localization and mapping has been studied by the mobile robotics scientific community over the last two decades. Most solutions for this problem are based on probabilistic theory in order to represent the uncertainty in robot perception and action. One of the most efficient probabilistic methods is the extended Kalman filter (EKF). However, the EKF demands a considerable amount of computing power and is usually processed by high-end laptops coupled to the robots. In this work, we present an implementation of the EKF targeting an embedded system based on an FPGA device. In order to improve performance, our approach combines a softcore processor with customized hardware. We present experiments with four different FPGA implementations, being the first purely based on software, the second using custom instruction logic directly connected to the processor's ALU, the third using hardware accelerators connected to the processor's data bus, and finally the fourth combining those two hardware/software solutions. For the experiments conducted, the results obtained with a small addition of hardware resources permitted to increase from 2times to 4times the performance of the global system.

Question Generation based on Lexico-Syntactic Patterns Learned from the Web

Abstract: THE MENTOR automatically generates multiple-choice tests from a given text. This tool aims at supporting the dialogue system of the FalaComigo project, as one of FalaComigo’s goals is the interaction with tourists through questions/answers and quizzes about their visit. In a minimally supervised learning process and by leveraging the redundancy and linguistic variability of the Web, THE MENTOR learns lexico-syntactic patterns using a set of question/answer seeds. Afterwards, these patterns are used to match the sentences from which new questions (and answers) can be generated. Finally, several filters are applied in order to discard low quality items. In this paper we detail the question generation task as performed by T- Mand evaluate its performance.