Triggering and event building results using the C104 packet routing chip

The C104 is an asynchronous 32-way dynamic packet routing chip. It has a 264Mbytes/s bi-directional bandwidth and a 1 µsec switching latency. It offers high-density cost- effective commodity communications, which allow large switching networks to be con- structed. Results are presented on the performance of this switching technology within the context of future High Energy Physics level II and level III trigger data traffic patterns

Combined Active Noise Control and noise reduction in Hearing Aids

International audienceThis paper presents a combined active noise control and noise reduction scheme for hearing aids to tackle secondary path effects and effects of signal leakage through the fitting. While such leakage contributions and the secondary accoustic path from the reciever to the tympanic membrane are usually not taken into account in standard noise reduction systems, they appear to have a non-negligible impact on the final signal quality. Integrating an active noise control system in the existing noise reduction algorithm helps to compensate for these effects. A Filtered-x Multichannel Wiener Filter is presented and compared experimentally with a classic Multichannel Wiener Filter in a noise reduction framework

Brief report: Follow-up outcomes of Multisystemic Therapy for adolescents with intellectual disabilities and the influence of parental intellectual disability

Research on follow‐up outcomes of systemic interventions for family members with an intellectual disability is scarce. In this study, short‐term and long‐term follow‐up outcomes of multisystemic therapy for adolescents with antisocial or delinquent behaviour and an intellectual disability (MST‐ID) are reported. In addition, the role of parental intellectual disability was examined. Outcomes of 55 families who had received MST‐ID were assessed at the end of treatment and at 6‐month, 12‐month and 18‐month follow‐up. Parental intellectual disability was used as a predictor of treatment outcomes. Missing data were handled using multiple imputation. Rule‐breaking behaviour of adolescents declined during treatment and stabilized until 18 months post‐treatment. The presence or absence of parental intellectual disability did not predict treatment outcomes. This study was the first to report long‐term outcomes of MST‐ID. The intervention achieved similar results in families with and without parents with an intellectual disability

Shimura varieties in the Torelli locus via Galois coverings of elliptic curves

We study Shimura subvarieties of $\mathsf{A}_g$ obtained from families of Galois coverings $f: C \rightarrow C'$ where $C'$ is a smooth complex projective curve of genus $g' \geq 1$ and $g= g(C)$. We give the complete list of all such families that satisfy a simple sufficient condition that ensures that the closure of the image of the family via the Torelli map yields a Shimura subvariety of $\mathsf{A}_g$ for $g' =1,2$ and for all $g \geq 2,4$ and for $g' > 2$ and $g \leq 9$. In a previous work of the first and second author together with A. Ghigi [FGP] similar computations were done in the case $g'=0$. Here we find 6 families of Galois coverings, all with $g' = 1$ and $g=2,3,4$ and we show that these are the only families with $g'=1$ satisfying this sufficient condition. We show that among these examples two families yield new Shimura subvarieties of $\mathsf{A}_g$, while the other examples arise from certain Shimura subvarieties of $\mathsf{A}_g$ already obtained as families of Galois coverings of $\mathbb{P}^1$ in [FGP]. Finally we prove that if a family satisfies this sufficient condition with $g'\geq 1$, then $g \leq 6g'+1$.Comment: 18 pages, to appear in Geometriae Dedicat

Adaptive NLMS Partial Crosstalk Cancellation in Digital Subscriber Lines

Crosstalk is a major limitation to achieving high data-rates in next generation VDSL systems. Whilst crosstalk cancellation can be applied to completely remove crosstalk, it is often too complex for application in typical VDSL binders, which can contain up to hundreds of lines. A practical alternative, known as partial cancellation limits the cancellation to crosstalkers that cause severe interference to the other lines within the binder. In real VDSL systems, the crosstalk environment changes rapidly as new lines come online; old lines go offline, and the crosstalk channels change with fluctuations in ambient temperature. Therefore, adaptive crosstalk cancellers are often required. In this paper, we propose a new detection guided adaptive NLMS method for Adaptive Partial Crosstalk Cancellation that detects significant crosstalkers and tracks variations in their crosstalk channels. This exploits the sparse and column-wise diagonal dominant properties of the crosstalk channel matrix and leads to fast convergence, accurate crosstalk channel tracking, with a lower update complexity. The end result is an adaptive Partial Crosstalk Cancellation algorithm that has lower run-time complexity than prior state-of-the-art whilst yielding comparatively high data-rates and reliable service

Intersymbol and Intercarrier Interference in OFDM Systems: Unified Formulation and Analysis

A unified matrix formulation is presented for the analysis of intersymbol and intercarrier interference in orthogonal frequency-division multiplexing (OFDM) systems. The proposed formulation relies on six parameters and allows studying various schemes, including those with windowing in the transmitter and/or in the receiver (called windowed OFDM systems), which may add cyclic suffix and/or cyclic prefix (CP), besides the conventional CP-OFDM. The proposed framework encompasses seven different OFDM systems. It considers the overlap-and-add procedure performed in the transmitter of windowed OFDM systems, being jointly formulated with the channel convolution. The intersymbol and intercarrier interference, caused when the order of the channel impulse response is higher than the number of CP samples, is characterized. A new equivalent channel matrix that is useful for calculating both the received signal and the interference power is defined and characterized. Unlike previous works, this new channel matrix has no restrictions on the length of the channel impulse response, which means that the study is not constrained to the particular case of two or three data blocks interfering in the received signal. Theoretical expressions for the powers of three different kinds of interference are derived. These expressions allow calculating the signal-to-interference-plus-noise ratio, useful for computing the data rate of each OFDM system. The proposed formulation is applied to realistic examples, showing its effectiveness through comparisons based on numerical performance assessments of the considered OFDM systems