A decidable subclass of finitary programs

Answer set programming - the most popular problem solving paradigm based on logic programs - has been recently extended to support uninterpreted function symbols. All of these approaches have some limitation. In this paper we propose a class of programs called FP2 that enjoys a different trade-off between expressiveness and complexity. FP2 programs enjoy the following unique combination of properties: (i) the ability of expressing predicates with infinite extensions; (ii) full support for predicates with arbitrary arity; (iii) decidability of FP2 membership checking; (iv) decidability of skeptical and credulous stable model reasoning for call-safe queries. Odd cycles are supported by composing FP2 programs with argument restricted programs

On finitely recursive programs

Disjunctive finitary programs are a class of logic programs admitting function symbols and hence infinite domains. They have very good computational properties, for example ground queries are decidable while in the general case the stable model semantics is highly undecidable. In this paper we prove that a larger class of programs, called finitely recursive programs, preserves most of the good properties of finitary programs under the stable model semantics, namely: (i) finitely recursive programs enjoy a compactness property; (ii) inconsistency checking and skeptical reasoning are semidecidable; (iii) skeptical resolution is complete for normal finitely recursive programs. Moreover, we show how to check inconsistency and answer skeptical queries using finite subsets of the ground program instantiation. We achieve this by extending the splitting sequence theorem by Lifschitz and Turner: We prove that if the input program P is finitely recursive, then the partial stable models determined by any smooth splitting omega-sequence converge to a stable model of P.Comment: 26 pages, Preliminary version in Proc. of ICLP 2007, Best paper awar

EU consumers' perception of fresh-cut fruit and vegetables attributes: a choice experiment model

Abstract: This thesis aims to study consumers’ perception in relation to fresh-cut fruit and vegetables consumption. In the first part of the work, the main features of the European freshcut fruit and vegetables market are discussed, paying more focus on the Italian demand of fruit and vegetables. The middle part is mainly represented by a systematic review of the literature investigating factors affecting the food choice decisions of adults in relation to fruit and vegetable consumption, with more emphasis to fresh-cut produces. Finally, there is the experimental part, in which European consumers’ preferences of fresh-cut fruit and vegetables are investigated through an econometric analysis. The fresh-cut sector is constantly evolving and innovating in order to enhance quality and safety of products, which attributes are generally valued by consumers. Quality and safety are multifaceted attributes because they arise from a wide set of methods/technologies, therefore the knowledge about consumers’ preferences for food technologies is still matter of debate. The main objective of this thesis it to test whether new fresh-cut fruit and vegetables attributes influence consumers’ choices and preferences. At the same time, we are able to verify the influence of socio-demographic characteristics on consumers’ preferences. A Latent Class Multinomial Logit Model has been fitted for almost 1.500 consumers of four different European countries: Greece, Italy, Spain and United Kingdom, in order to divide the consumers in different latent classes based on their choice and their characteristics. Fresh-cut F&V consumers for the four European countries, have a similar behavior in terms of preferences. We can divide the consumers in two different latent classes: the first made by consumers that do not appreciate any fresh-cut F&V attributes, and the second that include consumers that appreciate the several fresh-cut F&V attributes. Even if the cross-country comparison of consumers’ preferences has not produced substantial differences across the different countries, socio-demographic characteristics influence the perception of consumers about the consumption of fresh-cut fruit and vegetables

Exploring Sentiment Analysis on Twitter: Investigating Public Opinion on Migration in Brazil from 2015 to 2020

openTechnology has reshaped societal interaction and the expression of opinions. Migration is a prominent trend, and analysing social media discussions provides insights into societal perspectives. This thesis explores how events between 2015 and 2020 impacted Brazilian sentiment on Twitter about migrants and refugees. Its aim was to uncover the influence of key sociopolitical events on public sentiment, clarifying how these echoed in the digital realm. Four key objectives guided this research: (a) understanding public opinions on migrants and refugees, (b) investigating how events influenced Twitter sentiment, (c) identifying terms used in migration-related tweets, and (d) tracking sentiment shifts, especially concerning changes in government. Sentiment analysis using VADER (Valence Aware Dictionary and sEntiment Reasoner) was employed to analyse tweet data. The use of computational methods in social sciences is gaining traction, yet no analysis has been conducted before to understand the sentiments of the Brazilian population regarding migration. The analysis underscored Twitter's role in reflecting and shaping public discourse, offering insights into how major events influenced discussions on migration. In conclusion, this study illuminated the landscape of Brazilian sentiment on migration, emphasizing the significance of innovative social media analysis methodologies for policymaking and societal inclusivity in the digital age

La relazione tra autenticità e "construal level": analisi sperimentale nel settore del lusso.

Il presente lavoro farà emergere come, in un determinato contesto e sulla base di immaginazioni e rappresentazioni mentali di azioni, eventi e oggetti provocate da stimoli esterni ben definiti, gli individui producono i loro giudizi e le loro valutazioni. Nel dettaglio, l’obiettivo della ricerca è analizzare, attraverso uno studio sperimentale, il ruolo del construal level, e quindi, del modo in cui le persone percepiscono e interpretano la realtà, nella valutazione di autenticità su offerte di mercato di brand di lusso. La tesi si compone di tre parti centrali: la dissertazione teorica, nella quale si analizzano, i principali paper scientifici di riferimento per i costrutti teorici oggetto di studio, quali l’autenticità, la distanza psicologica e la construal level theory, e altri contributi fondamentali per la comprensione delle strategie di marketing e del consumo dei beni di lusso; il metodo della ricerca, dove sono illustrate le viarie fasi seguite per la progettazione ed esecuzione dell’indagine empirica, volta al reperimento e all’analisi dei dati sul campo; l’analisi dei risultati, in cui vengono riportate le analisi statistiche e i risultati ottenuti con l’indagine svolta, evidenziando se le ipotesi della ricerca formulate sono state o meno verificate

Application of a comprehensive methodology for the evaluation of social innovations in rural communities

open4noThis project has received funding from the European Union’s Horizon 2020 Research and Innovation Program under Grant Agreement No. 677622 (H2020 SIMRA–Social Innovation in Marginalised Rural Areas–Project).Despite the growing interest in social innovation (SI) in agriculture, the literature lacks validated tools for evaluating such initiatives. This paper provides an empirical application of the evaluation approach developed within the H2020 SIMRA project to a pilot experience conducted in a rural area of Southern Italy. The value added by this case study is the application of the five types of criteria used by the OECD for the evaluation of development programs, which are commonly referred to as REEIS: relevance, effectiveness, efficiency, impact, and sustainability. This experiment demonstrates the adequacy of the evaluation framework in identifying strengths and weaknesses of the initiative, according to a multifaceted perspective. The overall evaluation proves that most indicators fall under the high (48%) and medium categories (36%), and only few indicators are low (16%). The usefulness of the evaluation results is manifold. First, this evaluation highlights relevant arguments to support the communication strategy addressed at civil society, therefore reinforcing the civic engagement of the initiative, which is the distinctive feature of SI. Second, it supports project managers in addressing interventions to face emerging weaknesses. Finally, the evaluation provides factual evidence to policy makers to perform cost-effective analysis of rural development policies.openBaselice A.; Prosperi M.; Marini Govigli V.; Lopolito A.Baselice A.; Prosperi M.; Marini Govigli V.; Lopolito A

The biofragmentable anastomosis ring in elective colon resections.

Methods. Sixty-eight patients underwent elective colon resection and ìntraperitoneal anastomosis wìth thè biofragmentable anastomosis ring (BAR). Results. Anastomotic dehiscence occurred in 3 patients (4.4%). Two of them had an end-to-end ileocolostomy using a 31 mm BAR. The anastomosis failure was due to ischaemic lesion of thè small bowel dose to thè ileocolostomy, probably caused by a mismatch between thè size of small bowel and that of thè BAR. Another patient experienced anastomosis dehiscence probably due to a faecal impaction into thè BAR. Forty-eight patients (70.5%) experienced troublesome constipation and evacuated after thè sixth postoperative day. A bowel obstruction proximal to thè BAR was documented in 4 cases who have been treated conservatively. Condmions. The low rate of major complications justify thè use of thè BAR in elective colon surgery, but thè surgeon must be aware of tedious postoperative obstructive episodes frequently encountered in this series

wKSR-NLM: An Ultrasound Despeckling Filter Based on Patch Ratio and Statistical Similarity

Ultrasound images are affected by the well known speckle phenomenon, that degrades their perceived quality. In recent years, several denoising approaches have been proposed. Among all, those belonging to the non-local (NL) family have shown interesting performance. The main difference among the proposed NL filters is the metric adopted for measuring the similarity between patches. Within this manuscript, a statistical metric based on the ratio between two patches is presented. Compared to other statistical measurements, the proposed one is able to take into account the texture of the patch, to consider a weighting kernel and to limit the computational burden. A comparative analysis with other despeckling filters is presented. The method provided good balance between noise reduction and details preserving both in case of simulated (by means of Field II software) and real (breast tumor) datasets