Andrea De Salve - Academia.edu (original) (raw)

Papers by Andrea De Salve

ACM Transactions on Internet Technology, Feb 23, 2023

2022 IEEE Symposium on Computers and Communications (ISCC), Jun 30, 2022

2023 IEEE Symposium on Computers and Communications (ISCC)

Online Social Networks and Media

Proceedings of the 2022 5th International Conference on Blockchain Technology and Applications

Sensors

Alzheimer’s disease (AD) is the most common form of dementia. Computer-aided diagnosis (CAD) can ... more Alzheimer’s disease (AD) is the most common form of dementia. Computer-aided diagnosis (CAD) can help in the early detection of associated cognitive impairment. The aim of this work is to improve the automatic detection of dementia in MRI brain data. For this purpose, we used an established pipeline that includes the registration, slicing, and classification steps. The contribution of this research was to investigate for the first time, to our knowledge, three current and promising deep convolutional models (ResNet, DenseNet, and EfficientNet) and two transformer-based architectures (MAE and DeiT) for mapping input images to clinical diagnosis. To allow a fair comparison, the experiments were performed on two publicly available datasets (ADNI and OASIS) using multiple benchmarks obtained by changing the number of slices per subject extracted from the available 3D voxels. The experiments showed that very deep ResNet and DenseNet models performed better than the shallow ResNet and VGG...

arXiv (Cornell University), Jun 7, 2022

ACM Transactions on Internet Technology

The blockchain technology has been gaining an increasing popularity for the last years, and smart... more The blockchain technology has been gaining an increasing popularity for the last years, and smart contracts are being used for a growing number of applications in several scenarios. The execution of smart contracts on public blockchains can be invoked by any user with a transaction, although in many scenarios there would be the need for restricting the right of executing smart contracts only to a restricted set of users. To help deal with this issue, this article proposes a system based on a popular access control framework called RT, Role-based Trust Management, to regulate smart contracts execution rights. The proposed system, called Layer 2 DecentrAlized Role-based Trust management (L2DART), implements the RT framework on a public blockchain, and it is designed as a layer-2 technology that involves both on-chain and off-chain functionalities to reduce the blockchain costs while keeping blockchain auditability, i.e., immutability and transparency. The on-chain costs of L2DART have...

La tesi propone ed esamina in modo sperimentale un algoritmo distribuito per la selezione di soci... more La tesi propone ed esamina in modo sperimentale un algoritmo distribuito per la selezione di social cache, in un nuovo modello di DOSN con P2P Dunbar-based social overlay, prendendo in considerazione caratteristiche strutturali (Ego Betweenness Centrality) e temporali dei nodi

Traditional Online Social Networks (OSNs), which are based on a single service provider, suffer s... more Traditional Online Social Networks (OSNs), which are based on a single service provider, suffer several drawbacks, first of all the privacy issues arising from the delegation of user data to a single entity, the OSN provider. In the last years, Distributed Online Social Networks (DOSNs) have been proposed to shift the control over user data from the OSN provider to the users of the DOSN themselves. Indeed, in contrast to centralized OSNs (such as Facebook), DOSNs are not based on centralized storage services which decide the term of service and the contents shared by the users are stored on the devices of the users themselves. However, the lack of a centralized entity introduces new interesting challenges, like that of guaranteeing the availability of user’s contents when the user disconnects from the DOSN and the privacy of the user’s contents. In this dissertation we investigate the problem of preserving the privacy of the contents shared by users of DOSNs by focusing on two diffe...

Future Generation Computer Systems, Dec 31, 2023

2021 4th International Conference on Blockchain Technology and Applications, 2021

Decentralized Applications have become of paramount importance, especially thanks to the widespre... more Decentralized Applications have become of paramount importance, especially thanks to the widespread adoption of blockchains, such as Ethereum and EOS.IO, which are two of the most known platforms where such applications can be executed. Even if the goal of Ethereum and EOS.IO is very similar, the two projects have distinct capabilities and properties. For example, they use different consensus algorithms, different languages to program smart contracts, and allocate and manage on-chain resources in different ways. In this paper, we perform in-depth analysis of the models used by EOS.IO blockchain to manage its resources (i.e., ram, cpu and network bandwidth). For this purpose, we instantiate an EOS.IO-based Decentralized Application (DApp) implementing a Decentralized Rating Framework and we measure its resource requirements. Finally, we evaluate and compare the cost in fees required for running the DApp under three different resource management models provided by EOS.IO, which are the staking, rex, and power up models.

2021 IEEE 30th International Conference on Enabling Technologies: Infrastructure for Collaborative Enterprises (WETICE), 2021

2017 19th International Symposium on Symbolic and Numeric Algorithms for Scientific Computing (SYNASC), 2017

The advent of emerging information and communication technologies, such as RFID, small size senso... more The advent of emerging information and communication technologies, such as RFID, small size sensors and sensor networks, has made accessible a huge amount of information that requires sophisticated and efficient search algorithms to support queries on that data. In this paper we focus on the problem of aggregating data collected from these devices to efficiently support queries, inferences or statistics on them. In general, data aggregation techniques are necessary to efficiently collect information in a compact and cost-effective way. Some current solutions try to meet the above criteria, by exploiting different data aggregation techniques, for instance BitVector or Q_Digest. In this manuscript, we exploit the mathematical wavelet structure to define a sophisticated data aggregation technique for information collected from different nodes. The aggregated data is then exploited for solving multi-dimensional range queries. Experimental results based on simulations of a real dataset s...

ACM Transactions on Knowledge Discovery from Data, 2021

The widespread adoption of Online Social Networks (OSNs), the ever-increasing amount of informati... more The widespread adoption of Online Social Networks (OSNs), the ever-increasing amount of information produced by their users, and the corresponding capacity to influence markets, politics, and society, have led both industrial and academic researchers to focus on how such systems could be influenced . While previous work has mainly focused on measuring current influential users, contents, or pages on the overall OSNs, the problem of predicting influencers in OSNs has remained relatively unexplored from a research perspective. Indeed, one of the main characteristics of OSNs is the ability of users to create different groups types, as well as to join groups defined by other users, in order to share information and opinions. In this article, we formulate the Influencers Prediction problem in the context of groups created in OSNs, and we define a general framework and an effective methodology to predict which users will be able to influence the behavior of the other ones in a future time...

Lecture Notes in Computer Science, 2018

The usage of Online Social Networks (OSNs) has become a daily activity for billions of people tha... more The usage of Online Social Networks (OSNs) has become a daily activity for billions of people that share their contents and personal information with the other users. Regardless of the platform exploited to provide the OSNs’ services, these contents’ sharing could expose the OSNs’ users to a number of privacy risks if proper privacy-preserving mechanisms are not provided. Indeed, users must be able to define its own privacy policies that are exploited by the OSN to regulate access to the shared contents. To reduce such users’ privacy risks, we propose a Privacy Policies Recommended System (PPRS) that assists the users in defining their own privacy policies. Besides suggesting the most appropriate privacy policies to end users, the proposed system is able to exploits a certain set of properties (or attributes) of the users to define permissions on the shared contents. The evaluation results based on real OSN dataset show that our approach classifies users with a higher accuracy by recommending specific privacy policies for different communities of the users’ friends.

The wide diffusion of Online Social Networks (OSNs) presents several advantages, like the definit... more 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 behaviour is required. Unfortunately, the lack of real datasets limits the research in this field. The goal of this paper is the study of the behaviour of users in a real social network in order to define proper strategies to allocate the users’ data on the DOSN nodes. In particular, we present a...

In the visionary view of the future Internet, named the Next Generation Internet, a current idea ... more In the visionary view of the future Internet, named the Next Generation Internet, a current idea is to have a user-centric approach where human behavior models will be used to define the networks or to manage services. During the last years, a great trend in current Social Media platforms is to offer the opportunity to establish and join groups of people online. Despite human behaviour in current Online Social Media have been studied in depth, characteristics of these aggregations of people in content-based communities are still unknown. In this paper, we propose an evaluation of micro-communities of users inside the big network of Facebook groups to understand how and when users are active, and to evaluate the evolution of these micro-communities over time. Results show that almost all groups showed interactions-based communities. We found out that in all cases there is one massive core community which attracts small communities.