Search results for " Network"
showing 10 items of 6428 documents
An analysis of ego network communities and temporal a affinity for online social networks
2017
The wide diffusion of Online Social Networks (OSNs) presents several advantages, like the definition of simple tools for information sharing and spreading. However, OSNs present also some drawbacks, one of the most important one is the problem of privacy disclosures. Distributed Online Social Networks (DOSNs), which decentralize the control of the social network, have been recently proposed to overcome these issues. The decentralization of the control has issued several challenges, one of the main ones is guaranteeing data availability without relying on a central server. To define users’ data allocation strategies, the knowledge of the structure of the ego network and of the user’ temporal…
PRIVANET: An Efficient Pseudonym Changing and Management Framework for Vehicular Ad-Hoc Networks
2020
Protecting the location privacy is one of the main challenges in vehicular ad-hoc networks (VANETs). Although, standardization bodies, such as IEEE and ETSI, have adopted a pseudonym-based scheme as a solution for this problem, an efficient pseudonym changing and management is still an open issue. In this paper, we propose PRIVANET, a complete and efficient pseudonym changing and management framework. The PRIVANET has a hierarchical structure and considers the vehicular geographic area as a grid. Each cell of this grid contains one or many logical zones, called vehicular location privacy zones (VLPZs). These zones can easily be deployed over the widespread roadside infrastructures (RIs), su…
TeamSim: An Educational Micro-World for the Teaching of Team Dynamics
2008
In this paper we present an educational micro-world in which a learner can manipulate variables affecting the efficiency with which a team adapts to its environment. These include the structure of hierarchical relations within the team, the structure of the communications network, and other environmental parameters. Using the micro-world, the learner can design experiments (simulations) exploring notions in the dynamics of small groups. A freeware version of TeamSim is available from http:// laral.istc.cnr.it/gigliotta/.
Employing artificial neural networks to find reaction coordinates and pathways for self-assembly
2021
Capturing the autonomous self-assembly of molecular building blocks in computer simulations is a persistent challenge, requiring to model complex interactions and to access long time scales. Advanced sampling methods allow to bridge these time scales but typically require to construct accurate low-dimensional representations of the transition pathways. In this work, we demonstrate for the self-assembly of two single-stranded DNA fragments into a ring-like structure how autoencoder architectures based on unsupervised neural networks can be employed to reliably expose transition pathways and to provide a suitable low-dimensional representation. The assembly occurs as a two-step process throug…
An In-Depth Experimental Comparison of RNTNs and CNNs for Sentence Modeling
2017
The goal of modeling sentences is to accurately represent their meaning for different tasks. A variety of deep learning architectures have been proposed to model sentences, however, little is known about their comparative performance on a common ground, across a variety of datasets, and on the same level of optimization. In this paper, we provide such a novel comparison for two popular architectures, Recursive Neural Tensor Networks (RNTNs) and Convolutional Neural Networks (CNNs). Although RNTNs have been shown to work well in many cases, they require intensive manual labeling due to the vanishing gradient problem. To enable an extensive comparison of the two architectures, this paper empl…
Social Networks as an Approach to Systematic review
2019
Whether we are in the process of designing a new empirical study or our interest lies in conducting a review study, a solid literature review is needed to acquire an accurate idea of the current state of affairs with regard to a phenomenon of interest. Even if we can find contributions to the literature by entering keywords in search engines, we need tools that can help us to structure all the contributions encountered in terms of their interrelations and impact. This article presents social network analysis as such a tool. Although social network analysis is commonly thought of as a method in a particular empirical study, where individuals and groups of participants are studied, we can vie…
ASR in Classroom Today : Automatic Visualization of Conceptual Network in Science Classrooms
2017
Automatic Speech Recognition (ASR) field has improved substantially in the last years. We are in a point never saw before, where we can apply such algorithms in non-ideal conditions such as real classrooms. In these scenarios it is still not possible to reach perfect recognition rates, however we can already take advantage of these improvements. This paper shows preliminary results using ASR in Chilean and Finnish middle and high school to automatically provide teachers a visualization of the structure of concepts present in their discourse in science classrooms. These visualizations are conceptual networks that relate key concepts used by the teacher. This is an interesting tool that gives…
An Analysis of the Internal Organization of Facebook Groups
2019
With the rapid development and growth of online social networks (OSNs), researchers have been pushed forward to improve the knowledge of these complex networks by analyzing several aspects, such as the types of social media, the structural properties of the network, or the interaction patterns among users. In particular, a relevant effort has been devoted to the study and identification of cohesive groups of users in OSNs (also referred as communities) because they are the basic building block of each OSN. While several research works on groups in OSNs have mainly focused on identifying the types of groups and the contents created by their members, the analysis of internal organizations of …
Using the fibre structure of paper to determine authenticity of the documents: analysis of transmitted light images of stamps and banknotes.
2014
A novel method is presented for distinguishing postal stamp forgeries and counterfeit banknotes from genuine samples. The method is based on analyzing differences in paper fibre networks. The main tool is a curvelet-based algorithm for measuring overall fibre orientation distribution and quantifying anisotropy. Using a couple of more appropriate parameters makes it possible to distinguish forgeries from genuine originals as concentrated point clouds in two- or three-dimensional parameter space.
Determinants of user behaviour and recommendation in social networks
2014
Purpose – The purpose of this paper is to analyse the determinants of social network use behaviour using Theory of Planned Behaviour (TPB) and Uses and Gratifications Theory. Design/methodology/approach – A quantitative study was carried out with data gathered by personal interview using a structured questionnaire. Relationships proposed in the theoretical model were estimated through structural equation models. In total, 811 users of social networks over 14 and residents in Spain were part of the sample. Findings – Results indicate that use attitude and the subjective norm, both TPB variables, directly and significantly influence social network loyalty. Thus, network loyalty can be achiev…