Search results for "DW"
showing 10 items of 2700 documents
A Metaheuristic Bandwidth Allocation Scheme for FiWi Networks Using Ant Colony Optimization
2015
Optical-wireless access networks constitute a quite attractive solution to meet the ever-increasing bandwidth requirements of end-users, offering significant benefits such as ubiquitous coverage in the wireless domain and huge bandwidth in the optical domain. However, converging optical and wireless networking technologies, with Passive Optical Networks (PONs) and 4G wireless standards, such as the Worldwide Interoperability for Microwave Access (WiMAX) and the Long Term Evolution (LTE), entails major challenges that need to be addressed. In this context, designing an efficient and fair bandwidth distribution with Quality of Service (QoS) support is a difficult task due to the interdependen…
X-shooter spectroscopy of young stars with disks. The TW Hydrae association as a probe of the final stages of disk accretion
2019
We investigate ongoing accretion activity in young stars in the TW Hydrae association (TWA, ~8-10 Myr), an ideal target to probe the final stages of disk accretion down to brown dwarf masses. Our sample comprises eleven TWA members with infrared excess, amounting to 85% of the total TWA population with disks, with spectral types between M0 and M9, and masses between 0.58 and 0.02 Msol. We employed homogeneous spectroscopic data from 300 to 2500 nm, obtained with X-shooter, to derive individual extinction, stellar parameters, and accretion parameters simultaneously. We then examined Balmer lines and forbidden emission lines to probe the physics of the star-disk interaction environment. We de…
FPGA Implementation of an Adaptive Filter Robust to Impulsive Noise: Two Approaches
2011
Adaptive filters are used in a wide range of applications such as echo cancellation, noise cancellation, system identification, and prediction. Its hardware implementation becomes essential in many cases where real-time execution is needed. However, impulsive noise affects the proper operation of the filter and the adaptation process. This noise is one of the most damaging types of signal distortion, not always considered when implementing algorithms, particularly in specific hardware platforms. Field-programmable gate arrays (FPGAs) are used widely for real-time applications where timing requirements are strict. Nowadays, two main design processes can be followed for embedded system design…
An FPGA-Based Adaptive Fuzzy Coprocessor
2005
The architecture of a general purpose fuzzy logic coprocessor and its implementation on an FPGA based System on Chip is described. Thanks to its ability to support a fast dynamic reconfiguration of all its parameters, it is suitable for implementing adaptive fuzzy logic algorithms, or for the execution of different fuzzy algorithms in a time sharing fashion. The high throughput obtained using a pipelined structure and the efficient data organization allows significant increase of the computational capabilities strongly desired in applications with hard real-time constraints.
A distributed real-time data prediction and adaptive sensing approach for wireless sensor networks
2018
International audience; Many approaches have been proposed in the literature to reduce energy consumption in Wireless Sensor Networks (WSNs). Influenced by the fact that radio communication and sensing are considered to be the most energy consuming activities in such networks. Most of these approaches focused on either reducing the number of collected data using adaptive sampling techniques or on reducing the number of data transmitted over the network using prediction models. In this article, we propose a novel prediction-based data reduction method. furthermore, we combine it with an adaptive sampling rate technique, allowing us to significantly decrease energy consumption and extend the …
The visceral adiposity index is associated with insulin sensitivity and IGF-I levels in adults with growth hormone deficiency
2016
The visceral adiposity index, based on anthropometric and metabolic parameters, has been shown to be related to adipose tissue function and insulin sensitivity. We aimed to evaluate the performance of the visceral adiposity index in adult patients with growth hormone deficiency. We enrolled 52 patients(mean age 51 ± 13 years) with newly diagnosed growth hormone deficiency and 50 matched healthy subjects as controls at baseline. At baseline and after 12 and 24 months of treatment we evaluated anthropometric measures, lipid profile, glucose and insulin during an oral glucose tolerance test, hemoglobin A1c, homeostasis model assessment estimate of insulin resistance, quantitative insulin sensi…
Translation, adaptation and psychometric validation of the preterm birth experience and satisfaction scale (P-BESS) into Spanish.
2018
Abstract Background Preterm labour and birth are two of the most important issues in perinatal care. The birth of a preterm baby is often a stressful and traumatic time for parents. Assessment of satisfaction with maternity services is crucial and questionnaires are the most common method as long as they are well-constructed. Only one, The Preterm Birth Experience and Satisfaction Scale (P-BESS), developed in United Kingdom, has been designed for this specific birth type. Objectives To translate, transculturally adapt and assess the psychometric properties of the P-BESS into Spanish. Design Cross-sectional study. Setting Maternity unit of a tertiary level hospital in Spain. Participants A t…
Detection of sound rise time by adults with dyslexia
2005
Low sensitivity to amplitude modulated (AM) sounds is reported to be associated with dyslexia. An important aspect of amplitude modulation cycles are the rise and fall times within the sound. In this study, simplified stimuli equivalent to just one cycle were used and sensitivity to varying rise times was explored. Adult participants with dyslexia or compensated dyslexia and a control group performed a detection task with sound pairs of different rise times. Results showed that the participants with dyslexia differed from the control group in rise time detection and a correlation was found between rise time detection and reading and phonological skills. A subgroup of participants with lower…
Factors That Contribute or Impede the Physical Health Recovery of Women Exposed to Intimate Partner Violence: A Longitudinal Study
2012
Abstract Background Several cross-sectional studies have demonstrated the negative impact that intimate partner violence (IPV) has on the physical health of women. However, longitudinal studies are needed to establish the time course of this effect. This study assessed the physical health course of female IPV victims and established the factors that enhance or impede their recovery. Methods Women ( n = 91) who participated in a previous cross-sectional study (T-1) and were either victims of physical/psychological IPV ( n = 33) or psychological IPV ( n = 23) were evaluated 3 years later (T-2). A control group of women ( n = 35) was included for comparison. Structured interviews provided …
Diet supplementation during early lactation with non-alcoholic beer increases the antioxidant properties of breastmilk and decreases the oxidative da…
2013
After delivery and birth, mothers and neonates are exposed to oxidative stress. We tested whether supplementing the diet of breastfeeding mothers with non-alcoholic beer, a product rich in antioxidants, could improve their oxidative status and the antioxidant content of their milk. A prospective trial begun on Day 2 postpartum was conducted in mother-infant dyads.Sixty breastfeeding mothers and their infants were allocated to either a control group (n=30) on a free diet or a study group (n=30) on a free diet supplemented with 660 mL of non-alcoholic beer/day. The oxidative status of the mothers' breastmilk, plasma, and urine and the infant's urine was analyzed on Days 2 and 30 postpartum. T…