Combined Time Synchronization and Channel Estimation for OFDM Based Multi-relay Networks

In this paper a new combined time and channel estimation method for OFDM based multi-relay networks is proposed. Based on the channel statistics knowledge at the receiver, a maximum a posteriori estimate (MAP) of the channel impulse response is derived. Based on the channel estimate, we discern for the timing error. Computer simulations are presented to corroborate our analytical results.     

A comparative study on the performance of dye removal,from aqueous suspension,using (2-hydroxypropyl)-β-cyclodextrin-CS,PVP-PVA-CS,PVA-CS,PVP-CS and plain CS microspheres

This paper reports the results of the study on the performance of the removal of Cibacron Brilliant Yellow 3G-P and Calmagite, from aqueous solution, using either prepared 2-hydroxypropyl-β-cyclodextrin-chitosan [HPβCD-CS], poly(vinylalcohol)-polyvinylpyrrolidone-chitosan [PVA-PVP-CS], Poly(vinylalcohol)-chitosan [PVA-CS], polyvinylpyrrolidone-chitosan [PVP-CS] or plain chitosan microspheres [CS]. Modified CS molecules were analysed using FT-IR and TG-DTA techniques. Adsorption experiments were carried out and compared through varying mass ratio, contact time, initial dye concentration and temperature. Among the five studied adsorbents, the highest adsorption capacity was reached using HPβCD-CS. Kinetic equations were applied and the first-order model was shown to fit the adsorption phenomenon. The applicability of Langmuir, Freundlich, Temkin and Dubinin–Radushkevich equations was tested and the Langmuir isotherm exhibited the best fit with the experimental data. Data gleaned from both modelling and thermodynamic results indicate that the adsorption follows a physical and exothermic process.     

Fully Transparent Friction‐Modulation Haptic Device Based on Piezoelectric Thin Film

Standing Lamb waves in vibrating plates enable haptic interfaces. If the out‐of‐plane displacement of these waves exceeds 1 µm at frequencies above 25 kHz, a silent friction modulation can be created between a human finger and a vibrating plate. A fully transparent friction‐modulation haptic device based on a piezoelectric thin film is demonstrated. The antisymmetric Lamb mode induced at 73 kHz allows for a functional performance that fulfills all conditions for practical use. Out‐of‐plane displacement reaches 2.9 µm when 150 V unipolar voltage is applied. The average transmittance of the whole transducer reaches 75%. The key points of this technology are: 1) a thin HfO₂ layer between lead zirconate titanate film and substrate that prevents chemical reaction between them; 2) the efficient integration of transparent indium tin oxide electrodes and solution‐derived piezoelectric lead zirconate titanate thin film onto optical‐grade fused silica; and 3) the use of a transparent insulating layer made of SU‐8 photoresist.     

A comprehensive and holistic knowledge model for cloud privacy protection

The Journal of Supercomputing - Although Cloud computing is gaining popularity by supporting data analysis in an outsourced and cost-effective way, it brings serious privacy issues when sending the...     

Practical Application of Fractional Order Controllers to a Delay Thermal System

This paper provides an application of Fractional Model Predictive Control (FMPC) and fractional-order Proportional Integral controller (P I^λ) on a thermalsystem with time delay.The first controller is based on Grünwald-Letnikov’s method to predict the future dynamic behavior of the system. This methodconsists in replacing the non-integer derivation operator of the adopted system representation by a discrete approximation. Therefore, this controller isdeveloped on the basis of a fractional order model. However, the second controller is founded on an extended version of Hermite-Biehler theorem todetermine the complete set stabilizing P I^λ parameters Experiment results onto a time delay thermal system are given to illustrate the effectiveness of thedeveloped strategies.     

Object proposals for salient object segmentation in videos

Multimedia Tools and Applications - Salient object segmentation in videos is generally broken up in a video segmentation part and a saliency assignment part. Recently, object proposals, which are...     

Correction of pathological speeches and assistance to learners with vocal disabilities

This work describes a new methodology for correcting voice defects contained in the Arabic speeches and assisting learners of Arabic vocabulary. For this purpose, we follow four stages. The first step consists in localizing the vocal disabilities which degrade an Arabic voice signal, so we focus on comparing between a referenced probabilistic-phonetic model and a speaker model. Second, we differentiate two cases: Degraded speeches can be generated from pathological problems, or it can be produced by non arabophone learners. Hence, we compare between forced alignment scores. Third, we develop a new algorithm to correct pathological pronunciations. The last task is the conception of an application assisting learners of Arabic vocabulary in improving their pronunciation. The achieved results are encouraging. Moreover, learners of Arabic vocabulary have presented a good amelioration using the developed application. A lot of applications that design systems of voice signal processing can use our proposition.     

Water Addition During Oil Extraction Affects on Virgin Olive Oil Ethanol Content,Quality and Composition

Ethanol is the alcoholic precursor of fatty acid ethyl esters (FAEEs) in virgin olive oil (VOO). Because of its miscibility, water addition during oil extraction may affect oil ethanol content and then, the FAEEs synthesis during oil storage. In this work, the effect of water addition on VOO ethanol content and composition is studied. Water addition at two extraction systems (two and three phases) is compared and for vertical centrifuge, water addition at different temperatures is assayed. Ethanol content, quality parameters, and healthy components are determined in the oils. Results indicate three phase system gives oils with a 25% lower ethanol content than two phases. Ethanol reduction because of water addition is more important for three phases system (≈14%). For vertical centrifugation, ethanol is lowered as water dose and temperature increase. In general, water addition for any of the extraction steps analyzed reduces the oil ethanol concentration but other aspects such as fruity intensity and phenol content are also lowered. Practical applications: Virgin olive oil final ethanol content, and then its FAEEs concentration, does not only depend on the health and conservation status of olives, but also on the extraction system used and the amount of water added to the extraction process. The knowledge of the impact on ethanol content of water addition during oil extraction can be useful for olive oil legislators in order to keep the approved limits of FAEEs or to modify them. For oil producers, results can help to reduce the oil ethanol content and then FAEEs synthesis during virgin olive oil storage.     

An Effective and Accurate Methodology for the Cell Internal Defect Diagnosis

In this paper we propose an accurate methodology to diagnose cell internal defects, including defects caused by neighboured lines and defects caused by defective contacts. This methodology uses a precise intra-gate fault dictionary containing potential cell internal defects’ signatures to determine with precision the cell internal defect that explain the failures observed on the tester. The proposed methodology gives accurate results since it is based on the use of physical information extracted from library cells’ layout to create the intra-gate fault dictionary. Our method allows the diagnosis of cell internal defects in presence of different multiple fault configurations and volume data. Experiments are performed on industrial designs in which different types of multiple faults were injected with cell internal defects. The correct fault locations and causes are well predicted in all cases.     

Improving Néel Domain Walls Dynamics and Skyrmion Stability Using He Ion Irradiation

Ion irradiation with light ions is an appealing way to finely tune the magnetic properties of thin magnetic films and in particular the perpendicular magnetic anisotropy (PMA). In this work, the effect of He⁺ irradiation on the magnetization reversal and on the domain wall dynamics  of Pt/Co/AlOx trilayers is illustrated. Fluences up to 1.5 × 10¹⁵ ions cm⁻² strongly decrease the PMA, without affecting neither the spontaneous magnetization nor the strength of the interfacial Dzyaloshinskii–Moriya interaction (DMI). This confirms experimentally the robustness of the DMI interaction against interfacial chemical intermixing, already predicted by theory. In parallel with the decrease of the PMA, a strong decrease of the domain wall depinning field is observed after irradiation. This allows the domain walls to reach large maximum velocities with a lower magnetic field compared to that needed for the pristine films. Decoupling PMA from DMI can, therefore, be beneficial for the design of low energy devices based on domain wall dynamics. When the samples are irradiated with larger He⁺ fluences, the magnetization gets close to the out-of-plane/in-plane reorientation transition, where ≈100nm size magnetic skyrmions are stabilized. It is observed that as the He⁺ fluence increases, the skyrmion size decreases while these magnetic textures become more stable against the application of an external magnetic field, as predicted by theoretical models developed for ultrathin films with labyrinthine domains.