Valentina  Poggioni

Dr. Valentina Poggioni

Department of Mathematics and Computer Science, University of Perugia, 06123 Perugia, Italy
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Research Focus & Metrics

Academic Career Length

10Years (2017-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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2 January 2020 in Mathematics
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Journal Article
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MBMarco Baioletti
Marco Baioletti
GBGabriele Di Bari
Gabriele Di Bari
Alfredo MilaniAlfredo Milani
Alfredo Milani
VPValentina Poggioni
Valentina Poggioni
In this paper, a Neural Networks optimizer based on Self-adaptive Differential Evolution is presented. This optimizer applies mutation and crossover operators in a new way, taking into account the structure of the network according to a per layer strategy. Moreover, a new crossover called interm is proposed, and a new self-adaptive version of DE called MAB-ShaDE is suggested to reduce the number of parameters. The framework has been tested on some well-known classification problems and a comparative study on the various combinations of self-adaptive methods, mutation, and crossover operators available in literature is performed. Experimental results show that DENN reaches good performances in terms of accuracy, better than or at least comparable with those obtained by backpropagation.

27 September 2021 in Journal of Computer Information Systems
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Journal Article
Closed access
MAMohamad Almgerbi
Mohamad Almgerbi
Andrea De MauroAndrea De Mauro
Andrea De Mauro
AKAdham Kahlawi
Adham Kahlawi
VPValentina Poggioni
Valentina Poggioni
Data analytics’ growing importance in modern business has left many organizations unprepared in terms of human talent. This study sheds light on the intersection between the analytics job skills currently in demand and the offer of massive online open courses for developing them. We have scraped from the web the description of more than 14,000 job posts and 3,600 Data Analytics online courses to systematically capture the need for data skills and available learning opportunities. By using an original combination of topic modeling and text mining algorithms, we provide a systematic mapping of educational offers with business needs, quantifying their presence and identifying gaps. Our study enables both educational providers to improve their offering on Data Analytics and Human Resources professionals to identify skill development opportunities. Additionally, we introduce a general methodology able to produce systematic mappings of job skills and learning opportunities in any domain.

26 January 2022 in Sensors
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Alina Elena BaiaAlina Elena Baia
Alina Elena Baia
Giulio BiondiGiulio Biondi
Giulio Biondi
Valentina FranzoniValentina Franzoni
Valentina Franzoni
Alfredo MilaniAlfredo Milani
Alfredo Milani
VPValentina Poggioni
Valentina Poggioni
Deep learning approaches for facial Emotion Recognition (ER) obtain high accuracy on basic models, e.g., Ekman’s models, in the specific domain of facial emotional expressions. Thus, facial tracking of users’ emotions could be easily used against the right to privacy or for manipulative purposes. As recent studies have shown that deep learning models are susceptible to adversarial examples (images intentionally modified to fool a machine learning classifier) we propose to use them to preserve users’ privacy against ER. In this paper, we present a technique for generating Emotion Adversarial Attacks (EAAs). EAAs are performed applying well-known image filters inspired from Instagram, and a multi-objective evolutionary algorithm is used to determine the per-image best filters attacking combination. Experimental results on the well-known AffectNet dataset of facial expressions show that our approach successfully attacks emotion classifiers to protect user privacy. On the other hand, the quality of the images from the human perception point of view is maintained. Several experiments with different sequences of filters are run and show that the Attack Success Rate is very high, above 90% for every test.


11 May 2019 in Mathematics
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Journal Article
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UBUmberto Bartoccini
Umberto Bartoccini
ACArturo Carpi
Arturo Carpi
VPValentina Poggioni
Valentina Poggioni
Valentino SantucciValentino Santucci
Valentino Santucci
In this work, a coevolving memetic particle swarm optimization (CoMPSO) algorithm is presented. CoMPSO introduces the memetic evolution of local search operators in particle swarm optimization (PSO) continuous/discrete hybrid search spaces. The proposed solution allows one to overcome the rigidity of uniform local search strategies when applied to PSO. The key contribution is that memes provides each particle of a PSO scheme with the ability to adapt its exploration dynamics to the local characteristics of the search space landscape. The objective is obtained by an original hybrid continuous/discrete meme representation and a probabilistic co-evolving PSO scheme for discrete, continuous, or hybrid spaces. The coevolving memetic PSO evolves both the solutions and their associated memes, i.e. the local search operators. The proposed CoMPSO approach has been experimented on a standard suite of numerical optimization benchmark problems. Preliminary experimental results show that CoMPSO is competitive with respect to standard PSO and other memetic PSO schemes in literature, and its a promising starting point for further research in adaptive PSO local search operators.