An Efficient Mobile Data Gathering Method with Tree Clustering Algorithm in Wireless Sensor Networks Balanced and Unbalanced Topologies

Wireless Personal Communications - Electroencephalography (EEG) is a technique of Electrophysiology used in a wide variety of scientific studies and applications. Inadequately, many commercial...     

Nonlinear multi-scale decomposition by EMD for Co-Channel speaker identification

Multimedia Tools and Applications - A multi-scale analysis method, called Empirical Mode Decomposition (EMD), has been proposed for analysis of nonlinear and non stationary data. The empirical mode...     

Surgical technique in reduced hepatic transplantation in children

The lack of availability of pediatric donors for liver transplant has resulted in a high mortality rate among children awaiting transplantation, especially in patients weighing less than 10 kg. Knowledge of techniques of liver reduction allows liver transplantation in low-weight children with an adult liver graft, although with increased risk. The authors studied 70 pediatric liver transplants, 14.3% of whom received a reduced-size organ. Maximal difference between donor and recipient weight was 7.7. Segments II, III and IV (right hepatectomy) were transplanted in eight cases while segments II and III were transplanted in two cases. Transfusional requirements during the 48 hour postoperative period were not significantly different between patients with reduced-size liver and patients who received the full-size organ. There was not morbi-mortality secondary to surgical technique in reduced liver transplant group of patients.     

Noise wave techniques analysis applied to various planar microwave active filter topologies

This article deals with the improvement of noise figure for various topologies of microwave active filters. We show how, using a noise wave formalism, the noise factor of different filters can be analytically derived and effectively minimized. We validate our approach with simulated examples for each topology. © 1998 John Wiley & Sons, Inc. Int J RF and Microwave CAE 8: 116–130, 1998.     

Improved Geometric Anisotropic Diffusion Filter for Radiography Image Enhancement

In radiography imaging, contrast, sharpness and noise there are three fundamental factors that determine the image quality. Removing noise while preserving and sharpening image contours is a complicated task particularly for images with low contrast like radiography. This paper proposes a new anisotropic diffusion method for radiography image enhancement. The proposed method is based on the integration of geometric parameters derived from the local pixel intensity distribution in a nonlinear diffusion formulation that can concurrently perform the smoothing and the sharpening operations. The main novelty of the proposed anisotropic diffusion model is the ability to combine in one process noise reduction, edge preserving and sharpening. Experimental results using both synthetic and real welding radiography images prove the efficiency of the proposed method in comparison with other anisotropic diffusion methods.     

Dependence of the corrosion performance of polyaniline films applied on stainless steel on the nature of electropolymerisation solution

Polyaniline (PANI) films were deposited under cyclic voltammetric conditions on 304L stainless steel by aniline electropolymerisation from acidic and slightly basic solutions containing respectively the followed support-electrolytes: H₂C₂O₄ and KNO₃.It was found that the film produced in oxalic acidic medium was more conductive than that obtained in potassium nitrate one.The PANI coatings corrosion performances in 0.5 M NaCl were investigated and compared using standard electrochemical methods, electrochemical impedance spectroscopy (EIS) and SEM analysis.The highest corrosion resisting efficiency was obtained for PANI_nitrate which exhibited a significant physical barrier property against the attack of corrosive products. However, the corrosion protection of conductive PANI_oxalic coating was related to its catalytic behavior.     

Fuzzy Tree Clustering Algorithm with Mobile Data Collectors in Wireless Sensor Networks

In recent years, the need to deploy Wireless Sensor Networks increases in different applications. Several studies have been proposed to demonstrate the importance to use Mobile Data Collectors (MDC) in Wireless sensor Networks. The main goal of this paper is to reduce the energy consumption of sensor nodes and to extend the network lifetime. In this paper, we propose to construct a Minimum Spanning tree, we design a fuzzy Cluster Head election system to elect the best sensor nodes as Cluster Heads, considering two input parameters, namely the weight of Sensor Nodes (WoSN) and the State of Sensor Node Locations (SoSNLoc). To extend the network lifetime, a subset of MDCs travels the area to gather the sensed data from nodes instead of sending them directly to the Base Station (BS) in a single hop or multi-hop manner. The BS is located at the center of the area which will be divided into sub-regions, one for each MDC. According to their positions, each CH will belong to a specific region, and then will be visited by the corresponding MDC. Simulation results show the effectiveness of our proposed algorithm in terms of energy consumption and network lifetime in comparison with other ones.

     

Integration of Subjective and Objective Usability Evaluation Based on IEC/IEC 15939: A Case Study for Traffic Supervision Systems

Usability evaluation for interactive systems is one of the greatest interests for the Human–Computer Interaction community. To support this evaluation, several subjective and objective methods have been proposed and applied in academy and industry. In this context, usability evaluators usually work with a lot of and different kinds of data (e.g., ordinal values from questionnaires and performance rates) generated from different methods and tools and related to different usability criteria. In this article, we propose to integrate these data in a single way to better support the quality evaluators’ decision-making for traffic supervision systems domain. We apply the measurement information model defined by IEC/IEC 15939 with the use of indicators in an interactive system evaluation environment. Four indicators are presented from their specifications to their application in the evaluation of a system from a company. These indicators integrate evaluation results from usability questionnaires, an automated ergonomic guidelines inspector, and an electronic informer.     

Widgets Dedicated to User Interface Evaluation

In this article, evaluation-based widgets are proposed as a contribution to assist evaluators for early evaluation of user interfaces. This contribution imbricates the ergonomic quality evaluation process into widgets used for user-interface graphical composition. In other words, these widgets evaluate themselves according to a defined set of ergonomic guidelines. The proposed widgets indicate the possible interface design ergonomic inconsistencies as a notification to the designer. The guidelines set can be modified through an interface dedicated to guidelines definition into XML files. The proposed widgets are intended for the evaluation of different kind of user interfaces: WIMP, web, and mobile. An experimental evaluation, involving these evaluation-based widgets, is proposed to illustrate and to validate the approach.     

Firing behavior of argillites from northern Tunisia as raw materials for ceramic applications

This study reports the firing properties of clayey materials from northern Tunisia to evaluate their possible use as raw material in ceramic. Physical, chemical, and mineralogical characterization and thermal behavior were carried out by inductively coupled plasma atomic emission, X-ray diffraction, Fourier transform infrared spectroscopy, differential thermal analysis, particle size distribution, and Atterberg limits tests. Firing properties were evaluated by color, firing shrinkage, water absorption, bulk density, apparent porosity, and flexural strength. Studied clayey materials are made up mainly by kaolinite and illite and are rich in iron. The main transformations after thermal analysis were identified from 500°C to 1000°C subsequent to the dehydroxylation of clay minerals, calcite decomposition, and the recrystallization process. Fired samples up to 1100°C showed better physical and mechanical properties related with a great densification resulting in a significant increase in linear shrinkage, bulk density, and flexural strength and a decrease in apparent porosity and water absorption up to 1100°C. This behavior is due to a crystalline and liquid phases formed at low firing temperature associated with a high content of fluxing agents. The fired ceramic materials exhibited low water absorption up to 2.26% and high flexural strength up to 32.6 MPa, which makes their potential use for some earthenware and stoneware products.