This study provides an insight into the effectiveness of an optical network unit (ONU) sleep technique, where a subcomponent of the ONU is powered down during the absence of input traffic. The approach contributes to the realisation of advanced power efficiency over a wide range of input throughputs in situations where downstream traffic exceeds upstream traffic in recent residential networks. A numerical simulation showed that power-saving effectiveness could be achieved for an Mbit/s downstream throughput without latency implications in the Tx sleep mode.

The directional total variation (DTV) model has been proposed very recently for image denoising. However, the DTV model works well when there is just one dominant direction in the image. In this Letter, the authors propose to make the DTV model adaptive to image edge direction so that the proposed model can handle images with several dominant directions. Experiment and comparison show the effectiveness of the proposed method.

Infant cry is a multimodal and dynamic behaviour that it contains a lot of information. Goal of this investigation is recognition of two groups of infants by new acoustic feature that has not used in infant cry classification. The cry of deaf infants and normal hearing infants is studied. ‘Mel filter-bank discrete wavelet coefficients (MFDWCs)’ have been extracted as feature vector. Infant cry classification is a pattern recognition problem such as ‘automatic speech recognition’, which in signal processing stage the authors performed some pre-processing included silence elimination, filtering, pre-emphasising and, segmentation. After applying the discrete wavelet transform on the Mel scaled log filter bank energies of a cry signal frames, MFDWCs feature vector was extracted. The feature vector, MFDWCs, of each cry sample has large length, so they used principle components analysis to reduce in feature space dimension, after training of neural network as classifier, they achieved to 93.2% correction rate in cry recognition of test data set. This result shows better efficiency in comparison with previous familiarised approaches.

Based on the LuGre friction model, a sliding mode adaptive controller is presented to compensate for the friction in the servo system. The terminal switching function is selected as the sliding mode surface, which can make the error of the system converge to the equilibrium point in finite time. The main analytical result is a stability theorem for the proposed controller which can achieve asymptotical stability of the closed-loop system. Furthermore, the transient performance of the system is analytically quantified. To support the theoretical concepts, the authors present dynamic simulations for the proposed control scheme.

This Letter presents a detailed comparison of carbon nanotube field effect transistors (CNFETs) and metal oxide semiconductor field effect transistors (MOSFETs) with special focus on carbon nanotube FET's potential for implementing analogue circuits in the mm-wave and sub-terahertz range. The latest CNFET lithographic dimensions place it at-par with complementary metal oxide semiconductor in terms of current handling capability, whereas the forecasted improvement in the lithography enables the CNFETs to handle more than twice the current of MOSFETs. The comparison of RF parameters shows superior performance of CNFETs with a g_m , f _T and f _max of 2.7, 2.6 and 4.5 times higher, respectively. MOSFET- and CNFET-based inverter, three-stage ring oscillator and LC oscillator have been designed and compared as well. The CNFET-based inverters are found to be ten times faster, the ring oscillator demonstrates three times higher oscillation frequency and CNFET-based LC oscillator also shows improved performance than its MOSFET counterpart.