Non-asymptotic performance evaluation and sampling-based parameter estimation for communication networks with long memory traffic

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Energy Dissipation and Entropy Generation During the Fatigue Degradation: Application to Health Monitoring of Composites

In this dissertation, an experimental approach for characterizing energy dissipation and degradation evolution in a woven Epoxy/Glass (G10/FR4) laminate subjected to fully reversed bending fatigue test is presented. Infrared thermography and acoustic emission are utilized to characterize the degradation progression. The results show similar evolutionary response indicating the presence of three degradation stages. The effect of the surface cooling on the fatigue life of the laminates is investigated both experimentally and analytically. The results show that the life of the laminate is highly dependent on the temperature and that surface cooling can significantly increase the fatigue life of the laminate. The signatures of acoustic emission (AE) response emanating from laminates are studied. The distribution of the cumulative AE amplitude is described by a power law. Examination of the evolution of the probability density function (PDF) of the AE energy (counts) reveals two scaling zones wherein the transition from the low energy (count) to high energy (count) regime is identified. The low-energy phase represents very low damage state of the laminate characterized by a power law. The AE energy release and counts follow the statistics and power laws that do not depend on the operational conditions. A fatigue damage detection method for the laminates based on the cumulative information entropy is reported. The cumulative entropy demonstrates a persistent trend of nonlinear damage evolution typically observed in the experimental measures of the damage in composite materials. In this dissertation, a continuum formulation for irreversible energy dissipation that accounts for generated acoustic emissions during the loading of the materials is also developed. The evolution of the dissipative energy for AL6061 specimens is experimentally measured as the material is degraded. A statistically similar behavior is observed in different forms of the dissipated energy as the material degrade. Finally, a damage detection method for detection of wear in thrust ball bearings coated with molybdenum disulphide (MoS2) is presented. It employs an energy feature obtained from time-frequency representation of the vibration signal. Extensive experimental studies are conducted to verify the efficacy of the proposed method for fault diagnosis of MoS2 coating

Advances in Bioengineering

The technological approach and the high level of innovation make bioengineering extremely dynamic and this forces researchers to continuous updating. It involves the publication of the results of the latest scientific research. This book covers a wide range of aspects and issues related to advances in bioengineering research with a particular focus on innovative technologies and applications. The book consists of 13 scientific contributions divided in four sections: Materials Science; Biosensors. Electronics and Telemetry; Light Therapy; Computing and Analysis Techniques

On the Support of Massive Machine-to-Machine Traffic in Heterogeneous Networks and Fifth-Generation Cellular Networks

The widespread availability of many emerging services enabled by the Internet of Things (IoT) paradigm passes through the capability to provide long-range connectivity to a massive number of things, overcoming the well-known issues of ad-hoc, short-range networks. This scenario entails a lot of challenges, ranging from the concerns about the radio access network efficiency to the threats about the security of IoT networks. In this thesis, we will focus on wireless communication standards for long-range IoT as well as on fundamental research outcomes about IoT networks. After investigating how Machine-Type Communication (MTC) is supported nowadays, we will provide innovative solutions that i) satisfy the requirements in terms of scalability and latency, ii) employ a combination of licensed and license-free frequency bands, and iii) assure energy-efficiency and security