Vincenza Carchiolo

University of Catania | UNICT · Department of Electrical, Electronics and Computer Engineering (DIEEI)

The paper presents an algorithm to approach the problem of Maximum Clique Enumeration, a well known NP-hard problem that have several real world applications. The proposed solution, called LGP-MCE , exploits Geometric Deep Learning, a Machine Learning technique on graphs, to filter out nodes that do not belong to maximum cliques and then applies an...

In this paper we propose a method to reduce the running time to solve the Maximum Clique Enumeration (MCE) problem. Specifically, given a network we employ geometric deep learning in order to find a simpler network on which running the algorithm to derive the MCE. Our approach is based on finding a strategy to remove from the network nodes that are...

Co-authorship networks have been widely studied in recent years, but today new techniques and increasing computational power permit performing novel analysis and evaluate larger datasets. One of the emerging topic is the investigation of the reasons that determine the success of some people among the others. Researchers and academic community are o...

Centrality is a relevant topic in the field of network research, due to its various theoretical and practical implications. In general, all centrality metrics aim to measure the importance of nodes (according to some definition of importance) and such importance scores are used to rank the nodes in the network, therefore the rank improvement is a s...

The study of the behaviors of large community of researchers and what correlations exist between their environment, such as grouping rules by law or specific institution policies, and their performance is an important topic since it affects the metrics used to evaluate the quality of the research. Moreover, in several countries, such as Italy, thes...

Predicting new links in complex networks can have a large societal impact. In fact, many complex systems can be modeled through networks, and the meaning of the links depend on the system itself. For instance, in social networks, where the nodes are users, links represent relationships (such as acquaintance, friendship, etc.), whereas in informatio...

Training Artificial Neural Networks (ANNs) is a non-trivial task. In the last years, there has been a growing interest in the academic community in understanding how those structures work and what strategies can be adopted to improve the efficiency of the trained models. Thus, the novel approach proposed in this paper is the inclusion of the entrop...

The Italian academic community is an interesting case study of emerging collaborations among people that share interest in some topics. In this paper, we select and analyze three different research areas—defined by the Italian law “academic disciplines” (SSDs)—each with different topics and interests: computer engineering, mathematics and economics...

In this paper we analyze the bibliometrics of Italian academic researchers that belong to three “academic disciplines” (SSDs), topic-based groupings defined by law. In particular, we extract the data from Elsevier’s Scopus profiles of the researchers and analyze the impact of the SSDs and Research areas (ASJC) they belong to on various productivity...

A real-time news spreading is now available for everyone, especially thanks to Online Social Networks (OSNs) that easily endorse gate watching, so the collective intelligence and knowledge of dedicated communities are exploited to filter the news flow and to highlight and debate relevant topics. The main drawback is that the responsibility for judg...

Operations and maintenance of wind farms in renewable energy production are crucial to guarantee high availability and reduced downtime, saving at the same time the cost of energy produced. While SCADA or NLP-based techniques can be used to address maintenance tasks, efficient management of wind farms can be really achieved by adopting an intellige...

The provision of wellness in workplaces gained interest in recent decades. A factor that contributes significantly to workers’ health is their diet, especially when provided by canteen services. The assessment of such a service involves questions as food cost, its sustainability, quality, nutritional facts and variety, as well as employees’ health...

In a scenario where more and more individuals use online social network platforms as an instrument to propagate news without any control, it is necessary to design and implement new methods and techniques that guarantee the veracity of the disseminated news. In this paper, we propose a method to classify true and false news, commonly known as fake...

Business Process Management (BPM) is an accepted discipline and its importance for industrial automation is recognized by all players today. The complexity of modern management process will lead to chaos without a well-designed and effective BPM. Today, several tools exist, both commercial and open-source, but the selection of the appropriate tool...

Social Internet of Things can be viewed as the evolution of IoT in the same way social networks can be considered an evolution of the Internet. In this paper we present a social IoT approach based on a social broker paradigm. In our proposal, the sharing of information among entities requires a common semantic model to make the information meaningf...

Choosing an effective yet efficient solution to the link building problem means to select which nodes in a network should point a newcomer in order to increase its rank while limiting the cost of this operation (usually related to the number of such in-links). In this paper we consider different heuristics to address the question and we apply them...

Networks measurement is essential to catch and quantify their features, behaviour and/or emerging phenomena. The goal of cohesiveness metric introduced here is to establish the level of cohesion among network nodes. It comes from the Black-Hole metric introduced as a solution of the normalization problem that affects PageRank; in particular, here w...

Abstract Many systems are today modelled as complex networks, since this representation has been proven being an effective approach for understanding and controlling many real-world phenomena. A significant area of interest and research is that of networks robustness, which aims to explore to what extent a network keeps working when failures occur...

Smart homes, smart cities, smart everything and the Internet of Things (IoT) have incredible impact in our life. Typically, IoT devices are though vulnerable to attacks and the strategy to manage IoT security is influenced by the IoT model and the application field. Social Internet of Things (SIoT) can be viewed as the evolution of IoT in the same...

Basics of PageRank algorithm have been widely adopted in its variations, tailored for specific scenarios. In this work, we consider the Black Hole metric, an extension of the original PageRank that leverages a (bogus) black hole node to reduce the arc weights normalization effect. We further extend this approach by introducing several black holes t...

This work presents the solution used within STMicroelectronics to grant security in Mobile Cloud computing (MCC), where Cloud computing paradigma meets the mobile environment, the enabling technology to provide access network services anyplace, anytime and anywhere. We first illustrate the scenario, then MCC main issues are introduced, and the corr...

Location based services play a key role in creating fully automated and adaptive systems that support Supply Chain Management and complex inter-modal logistics. IoT technology allows companies to part from statistical analysis in favour of proactive management by leveraging data collected in real time from the goods and processes that sustain their...

Social networks are hugely used to spread information, and the understanding of mechanisms and behaviours leading the news diffusion process still deserves a major attention. In this paper we introduce the direct credibility among nodes, a parameter that takes into account their past interactions. We exploit this amount into a well-known epidemic m...

Network fault tolerance (also known as resilience or robustness) is becoming a highly relevant topic, expecially in real networks, where it is essential to know to what extent it is still working notwithstanding its failures. Different questions need attention to guarantee robustness, as how it can be effectively and efficiently (i.e. rapidly) asse...

The best attachment consists in finding a good strategy that allows a node inside a network to achieve a high rank. This is an open issue due to its intrinsic computational complexity and to the giant dimension of the involved networks. The ranking of a node has an important impact both in economics and structural term e.g., a higher rank could lev...

Misinformation spreading over online social networks is becoming more and more critical due to the huge amount of information sources whose reliability is hard to establish; moreover, several humans psychology factors as echo chambers and biased searches, plus the intensive use of bot, makes the scenario difficult to cope with. Unprecedented opport...

Ranking is a widely used technique to classify nodes in networks according to their relevance. Increasing one’s rank is a desiderable feature in almost any context; several approaches have been proposed to achieve this goal by exploiting in-links and/or out-links with other existing nodes. In this paper, we focus on the impact of in-links in rank i...

IoT based systems are significantly different from other mainly due to the multitude of parameters they can monitor and/or control. In medical home-care, these systems can make the whole service supply chain more efficient and safer. We discuss the case study of home-care oxygen therapy where continuous monitoring systems allow real-time access to...

In network science, there is often the need to sort the graph nodes. While the sorting strategy may be different, in general sorting is performed by exploiting the network structure. In particular, the metric PageRank has been used in the past decade in different ways to produce a ranking based on how many neighbors point to a specific node. PageRa...

Online social networks are overwhelmed with information spreading, phenomena whose underlying mechanisms require deeper analysis. In this paper, we introduce the direct credibility among nodes, a parameter that takes into account news trustworthiness. We exploit this amount into a well-known epidemic model to study the news diffusion process and to...

Social networks are intensively and extensively used to exchange news and contents in real time. The lack of a global authority for assessing posts truthfulness however allows malicious to exhibit unfair behaviours; identifying methodologies to detect hoaxes and defamatory content automatically is therefore more and more required. Social networks a...

Although the problem of partition quality evaluation is well-known in literature, most of the traditional approaches involve the application of a model built upon a theoretical foundation and then applied to real data. Conversely, this work presents a novel approach: it extracts a model from a network which partition in ground-truth communities is...

Ordering nodes by rank is a benchmark used in several contexts, from recommendation-based trust networks to e-commerce, search engines and websites ranking. In these scenarios, the node rank depends on the set of links the node establishes, hence it becomes important to choose appropriately the nodes to connect to. The problem of finding which node...

The exploitation of trust in virtual environments, on-line services, intelligent pervasive environments and many other scenarios still deserve researchers’ interest. In this work we investigate on how to assess the local (direct) trust a node receives from each of his neighbors. Our proposal is social-based and takes into account both positive and...

The participation to virtual contexts has been increased during the last decade. Trust is often used in such a scenario as a mechanism to establish reliable relationships. In addition, trust is often used to rank nodes in a network and the higher the rank the more preferred that node will be, therefore each node aims at getting a better position. S...

The act of learning is becoming more and more sophisticated, thanks to several models and tools available today, like MOOCs, personalization, social networks, Web 2.0, gamification and others. This vast landscape leads to a huge amount of datasets thus the Big Data paradigm is also being adopted. Joined with Big Data is the emergency of extracting...

Virtual interaction with strangers often makes use of underlying trust networks. Usually, existing proposals address the evaluation of global (unique) trust for a given node within the network. In this paper we discuss about how to assess the local (direct) trust a node receives from each of his neighbors. Our proposal is social-based and takes int...

Twitter has been recently used to predict and/or monitor real world outcomes, and this is also true for health related topic. In this work, we extract information about diseases from Twitter with spatiotemporal constraints, i.e. considering a specific geographic area during a given period. We exploit the SNOMED-CT terminology to correctly detect me...

The huge amount of data in the web made and is still making harder the issue of finding the right information. To help users in their choices, recommender systems are used as a valuable tool when dealing with innumerable choices of data, products and services. In this work, expertise is used to improve the quality of recommendations by selecting th...

The massive use of web based social networks endorse trustworthiness to establish reliable relationships. Trust is often used to rank entities hence during the attachment process in a trust network, newcomers aim at improving their rank. Moreover, since in real systems each new link implies some cost for the node, we also consider how many links (i...

The need of trust is growing in several contexts as e-commerce, virtual communities, distributed on-line services and many others as an essential precautionary component for users during interactions with strangers, either other people or virtual agents. Generally trust metrics endorse the principle "the higher the trust, the more legitimate that u...

Data integration of medical information to be stored in EMR, HER and/or PHR is a challenging issue, especially for the sensitive nature of such data. Here we present a simple tool for medical data integration for semistructured sources (as healthcare provider websites); to cope with semantics, SNOMED-CT clinical terminology is exploited. Final resu...

The combination of the interest in environmental questions on one hand and the massive use of web based social networks on the other recently led to a revival of carpooling. In particular, the exploitation of social networks promotes the information spreading for an effective service (e.g. reducing the lack of confidence among users) and endorses c...

Carpooling is currently getting more and more attractive thanks both to an increasing emphasis placed on environmental issues and to the huge use of web based social networks. They indeed (1) allow to spread all information for an effective service (2) compensate the lack of confidence among carpooling users (3) promote carpooling companies via vir...

Computer networks security is a hard issue, which continuously evolves due to the change of technologies, architectures and algorithms and the growing complexity of architectures and systems. This question is enforced in distributed contexts where the lack of a central authority imposes to set up a proper strategy for both passive and active securi...

Domotics is a promising area for intelligent and pervasive ap-plications that aims at achieving a better quality of life. Harnessing modern technologies is valuable in many contexts, in particular in home surveillance scenario, where people safety or security might be threatened. Modern home security systems endorse monitoring as well as control fu...

The shifting of computation and storage towards distributed, embedded and mobile systems encompasses several advantages, as the increasing in performance, scalability, and reduction of costs. A significant drawback though is the potential lack in security and trust, due to a huge number of different, dispersed devices. In such a context, trust-base...

The effect of the Internet on everyday life is huge, especially for what concerns the number and quality of our social relationships, including friendships and kinship. Fortunately, the complex network theory recently made it feasible to analyze real and large social networks, making it possible to understand their behavior and dynamics, including...

Trust and reputation systems gained great attention in the last decades. Such systems aim at giving users a quantitative evaluation about the trustworthiness of other users. Several metrics achieve it by combining the past direct experience of all the users of the trust network. Among the methods developed to assess trust, EigenTrust is one of the...

The increasing use of Internet in real world activities such as e-commerce, blogs, wikies and several others makes the question of trust a critical issue. However, everyone can push information on line, so it is not easy to get knowledge about trust from centralized authorities. Moreover, discovering trusted entities often stricly depends on what c...

Trust is a widespread mechanism to establish and conduct successful social collaborations, expecially in today's Internet, where people perform more and more activities on-line, from social networking to e-learning, e-commerce and others. Several algorithms are available for trust assessment, such as the well-known EigenTrust to PowerTrust, GossipT...

In the modern knowledge society it is becoming increasingly important to maintain and promote social connections; among these, the kinship allows people to keep in touch with their relatives. In this paper we present a proposal for building and enhancing kinship networks by exploring acquaintances and friend relationships, showing the effectiveness...

Domotics is a promising area for intelligent and pervasive applications that aims at achieving a better quality of life. Harnessing modern technologies is valuable in many contexts, in particular in home surveillance scenario, where people safety or security might be threatened. Modern home security systems endorse monitoring as well as control fun...

Currently several computer‐based scenarios leverage the concept of trust as a mean to make electronic interactions (e.g., e‐commerce transactions) as reliable as possible, allowing to cope with uncertainty and risks by recommending trusted peers. Generally, the evaluation of trustworthiness can be accomplished according to many principles, from soc...

A generic user can find a great number of on-line systems to access a huge amount of information. Unfortunately, usually there is no control about the quality of information. To deal with this issue, several trust and reputation systems have been developed in the last years, adopting several metrics as the well-known EigenTrust. In this paper we in...

Discovering communities in complex networks helps to understand the behaviour of the network. Some works in this promising research area exist, but communities uncovering in time-dependent and/or multiplex networks has not deeply investigated yet. In this paper, we propose a communities detection approach for multislice networks based on modularity...

The evolution of the Web 2.0 and the intensive use of peer-to-peer networks allow us to access more and more information from disparate data sources than in the past, thus making life-long learning more effective. In this scenario, a critical issue still remains to be addressed: the reliability of resources, whether they can be recommended as usefu...

Social networks study revealed several useful properties, as the small world effect; such networks can be exploited in addressing the question of trusting, which has become a crucial matter inside Internet-based communities. This paper presents such an approach aiming at reproducing the behaviour individuals adopt in their life when they establish...

Current manufacturing systems have a very structured production model, expecially when high complexity and precision is required, as in semiconductor devices manufacturing. In addition, rapid changes in both production and market requirements may occur, hence great flexibility is essential. This goals, together with the capability of adding new fea...

Nature is a great source of inspiration for scientists, because natural systems seem to be able to find the best way to solve a given problem by using simple and robust mechanisms. Studying complex natural systems, scientists usually find that simple local dynamics lead to sophisticated macroscopic structures and behaviour. It seems that some kind...

The growing of networks and the success of fully distributed mechanisms and protocols to exchange data - as peer-to-peer networks - emphasise the need of trustworthiness. Usually both trust and reputation are taken into account: the former expresses the direct experience, whereas the latter represents the common opinion of the whole network. Their...

Expertise assessment is frequently required in social networks. This work proposes a method to globally rank people according to their expertise according to a set of topicsWe also introduce contexts similarity to allow related contexts to be exploited in expertise assessment. These ideas are applied to the Epinions.com recommender systems, showing...

This paper presents a distributed algorithm capturing the TrustWebRank metric, whose goal is to evaluate trust relationships among users in a social network. We first justify why a distributed version of TrustWebRank is useful and then we assess its performances, both in terms of complexity and bandwidth, through several simulations performed using...

The pervasive computing paradigm promotes new applications in several scenarios. Among these, domotics is receiving a considerable attention. This work presents an intelligent and pervasive surveillance system for home and corporate security based on the ZigBee protocol which detects and classifies intrusions discarding false positives, also provid...

In the last decade the broad scope of complex networks has led to a rapid progress. In this area a particular interest has the study of community structures. The analysis of this type of structure requires the formalization of the intuitive concept of community and the definition of indices of goodness for the obtained results. A lot of algorithms...

Continuous changes in business processes due to market globalization calls for BPR to be frequently invoked within all industry activities; among these, the assessment of production through enterprise reports is fundamental to know whether and how the main goal (the manufacturing of products) is being accomplished. In this paper we present an effec...

Users trust management is one of the most important issues in the Internet. In fact, due to the distributed nature of many services it is not simple to assign an objective trust value to a user, especially in the presence of groups of malicious peers. In this paper we analyze the effect of group empowering on a gossip-based reputation system named...

The use of P2P approach in e-learning is an interesting solution in particular within lifelong learning. Generally, peer-to-peer paradigm is a successful solution to the problem of resources sharing. In this field there are two open questions. First, how to advertise learning objects on the network, so that peers knows they exist. Second, how to ch...

P2P communication paradigm is a successful solution to the problem of resources sharing as shown by the numerous real overlay networks present on Internet. One of the issue of P2P networks is how a resource shared by a peer can be made known to the other peers or, in other words, how to advertise a resource on the network. In this paper we propose...

Experts finding is a frequent issue in social (even web-based) networks. This work proposes a method to globally rank people according to their expertise in a set of topics. We also introduce contexts similarity to allow related contexts to be exploited during ranks assessment. These ideas are applied to the expertise network built from Epinions.co...

The personalisation of learning paths according to personal profiles is one of the major advantages of computer assisted learning. However, the choice of most suitable learning resources is sometime a controversial question due to different e-learning providers' assessment about each other and their learning resources. In this work, an approach to...

The personalization of learning paths according to personal profiles is one of the major advantages of computer assisted learning. However, the choice of most suitable learning resources is sometime a controversial question due to different e-learning providers assessment about each other and their learning resources. In this work an approach to ad...

Effective E–Learning requires ability to adapt in order to provide students with personalised learning path, based on specified goals and personal profiles, as well as the possibility of re-evaluating learning paths during the learning process based on actually learned topics. Moreover, shared teaching materials spread over the network, requiring a...

Complex networks topologies present interesting and surprising properties, such as community structures, which can be exploited to optimize communication, to find new efficient and context-aware routing algorithms or simply to understand the dynamics and meaning of relationships among nodes. Complex networks are gaining more and more importance as...

Networks seem to be the natural way chosen by nature to organise individuals, resources and interactions in an effective and robust structure. Studies about natural networks focused on the central role of emerging structures in distributed environments, and pointed out some properties such as small-world effect and communities which are of the most...

Trust is essential in human interaction and this naturally reflects within computer science context, in particular inside internet-based communities. In this work we present an approach based on social networks, which revealed several useful properties, as the small world effect, that can be usefully exploited in addressing the question of trust. W...