Search results for "NETWORKS"

Detecting cellular network anomalies using the knowledge discovery process

2015

Analytical companies unanimously forecast the exponential growth of mobile traffic consumption over the next five years. The densification of a network structure with small cells is regarded as a key solution to meet growing capacity demands. The manual management of a multi-layer network is a very expensive, error prone, and sluggish process. Hence, the automation of the whole life cycle of network operation is highly anticipated. To this aim 3GPP introduces a self-management concept referred to as SON. It is envisioned that SON updates information concerning the latest network conditions through the MDT mecha- nism. MDT enables a network operator to collect radio and service quality measurem…

Understanding the sense of community and continuance intention in virtual communities: The role of commitment and type of community

2019

Virtual communities (VCs) have become essential in current organizations and society, and so their sustainability is a topic of interest for researchers and practitioners. We focus on the sense of virtual community (SoVC) and commitment as relevant antecedents in achieving the success and maintenance of different types of VCs (communities of interest, virtual learning communities, and virtual communities of practice). Specifically, this study examines a moderated mediation model in which the type of virtual community moderates the indirect effect of a SoVC on the intention to continue through the perceived commitment of the users of the VC. The sample consists of 299 members of Virtual comm…

Opportunistic Synchronization for Improving IEEE 802.15.4 MAC Performance in Chain Topologies

2010

The most effective solution for energy saving in low-rate wireless sensor networks is maintaining each node in a doze state as long as possible. In order to guarantee network connectivity, the intervals at which the network sensors are turned on and off have to be coordinated. Therefore, synchronization is a very critical function for sensor networks. In this paper, we analyze the IEEE 802.15.4 MAC performance in sensor networks deployed in a chain topology. For this topology, critical inefficiencies can arise in case of multi-hop packet deliveries. We evaluate the impact of different synchronization schemes on the network performance, both in terms of network throughput and in terms of ene…

Sex-specific signatures of intrinsic hippocampal networks and regional integrity underlying cognitive status in multiple sclerosis

2021

Abstract The hippocampus is an anatomically compartmentalized structure embedded in highly wired networks that are essential for cognitive functions. The hippocampal vulnerability has been postulated in acute and chronic neuroinflammation in multiple sclerosis, while the patterns of occurring inflammation, neurodegeneration or compensation have not yet been described. Besides focal damage to hippocampal tissue, network disruption is an important contributor to cognitive decline in multiple sclerosis patients. We postulate sex-specific trajectories in hippocampal network reorganization and regional integrity and address their relationship to markers of neuroinflammation, cognitive/memory per…

Daphne II - Ve.R.S.O project: a new protocol for the management of sexual assault victims

2012

Daphne II - Ve.R.S.O project: a new protocol for the management of sexual assault victims. Sexual assault is a worldwide problem that has not yet been sufficiently acknowledged, as confirmed by analyses and studies carried out at different levels and in different contexts. Internationally, different approaches are taken to the collection of forensic evi- dence and to the clinical and psychological treatment of alleged victims. Italian law n.96, 1996, foreseeing norms regarding rape and abuse, finally gave signifi- cant relevance to sex crimes. In 2004, the European Commission for Justice Internal Affairs and Social Politics promoted the Daphne II pro- gram to support victims of rape and abu…

A sensitivity analysis on artificial neural networks fracture predictions in sheet metal forming operations

2008

Space-by-Time Modular Decomposition Effectively Describes Whole-Body Muscle Activity During Upright Reaching in Various Directions

2017

The modular control hypothesis suggests that motor commands are built from precoded modules whose specific combined recruitment can allow the performance of virtually any motor task. Despite considerable experimental support, this hypothesis remains tentative as classical findings of reduced dimensionality in muscle activity may also result from other constraints (biomechanical couplings, data averaging or low dimensionality of motor tasks). Here we assessed the effectiveness of modularity in describing muscle activity in a comprehensive experiment comprising 72 distinct point-to-point whole-body movements during which the activity of 30 muscles was recorded. To identify invariant modules o…

Comparison of Machine Learning Methods in Stochastic Skin Optical Model Inversion

2020

In this study, we compare six different machine learning methods in the inversion of a stochastic model for light propagation in layered media, and use the inverse models to estimate four parameters of the skin from the simulated data: melanin concentration, hemoglobin volume fraction, and thicknesses of epidermis and dermis. The aim of this study is to determine the best methods for stochastic model inversion in order to improve current methods in skin related cancer diagnostics and in the future develop a non-invasive way to measure the physical parameters of the skin based partially on the results of the study. Of the compared methods, which are convolutional neural network, multi-layer …

Advanced performance monitoring for self-healing cellular mobile networks

2015

This dissertation is devoted to development and validation of advanced per- formance monitoring system for existing and future cellular mobile networks. Knowledge mining techniques are employed for analysis of user specific logs, collected with Minimization of Drive Tests (MDT) functionality. Ever increas- ing quality requirements, expansion of the mobile networks and their extend- ing heterogeneity, call for effective automatic means of performance monitoring. Nowadays, network operation is mostly controlled manually through aggregated key performance indicators and statistical profiles. These methods are are not able to fully address the dynamism and complexity of modern mobile networks. Se…

A Telemetry, Tracking, and Command Antennas System for Small-Satellite Applications

2019

Circularly polarized (CP) antennas are used in space applications for telemetry tracking and command (TT&amp