1,720,964 research outputs found
Design and security assessment of blockchain-based techniques for digital identity, data certification and traceability
No full textLa crescente digitalizzazione genera un'enorme quantità di dati che rappresentano un asset estremamente importante. Tuttavia, garantirne l'integrità e la certificazione, così come garantire l'autenticità delle loro sorgenti, è una sfida cruciale. Infatti, le identità, i dati e i processi digitali devono essere sicuri e affidabili per garantire la privacy, la trasparenza e la fiducia degli utenti. La tecnologia blockchain si presenta come un metodo efficace per garantire la fiducia tra un insieme di utenti non fidati. Infatti, la natura distribuita della blockchain garantisce l'immutabilità dei dati senza la presenza di un'autorità centrale. La tecnologia blockchain è stata introdotta per la prima volta da Satoshi Nakamoto nel 2008 per creare un sistema finanziario decentralizzato, ma, grazie alle sue proprietà, è ora usata in molte applicazioni diverse. Anche la certificazione delle identità digitali e dei dati può trarre vantaggio dalla tecnologia blockchain. Infatti, le sue proprietà, come la decentralizzazione, l'immutabilità e la trasparenza, offrono un modo innovativo per gestire questi temi. Questa tesi esplora nuovi metodi basati sulla blockchain per gestire l'identità digitale, la certificazione dei dati e la tracciabilità, analizzando i rischi intrinseci e proponendo soluzioni per mitigarli. Proponiamo due diversi metodi per la certificazione e la tracciabilità dei dati, che possono essere applicati in diversi scenari. Questi approcci illustrano come la blockchain possa essere applicata per la certificazione e la verifica dei dati; allo stesso tempo, è importante anche garantire la protezione dei dati personali, come richiesto dalle normative nazionali e internazionali vigenti. Quindi, gli approcci proposti possono trovare applicazione, ad esempio, nel settore dei certificati accademici, nella gestione della supply chain e nei sistemi di verifica delle presenze. Successivamente, ci concentriamo sull'integrazione dei dispositivi embedded direttamente con i sistemi blockchain al fine di consentire l'acquisizione e la certificazione automatizzata dei dati, e diminuendo, quindi, la probabilità di manomissione. L'assenza di intermediari garantisce l'autenticità dei dati, oltre alla loro integrità. Per aumentare l'affidabilità dei dati, è molto importante autenticare la sorgente dei dati, che può essere sia un utente, sia un oggetto o dispositivo. Proponiamo, innanzitutto, un sistema di autenticazione biometrica integrato con la blockchain, che migliora la sicurezza ed elimina le vulnerabilità associate alla memorizzazione centralizzata di dati sensibili. Successivamente, proponiamo un nuovo meccanismo di consenso da utilizzare nei sistemi basati su blockchain che garantisce contemporaneamente l'autenticazione delle sorgenti fuzzy e il consenso sulla rete. Oltre ai vantaggi dell'applicazione della blockchain per l'identità digitale, la tracciabilità dei dati e la certificazione, è fondamentale valutare anche i rischi associati. Nella tesi, quindi, analizziamo alcuni rischi poco conosciuti, come i Data Availability Attack. In questo tipo di attacco, nodi malevoli impediscono la validazione di parti critiche di un blocco. Proponiamo una versione ottimizzata di un protocollo che affronta questi attacchi, consentendo ai nodi light di campionare casualmente i dati, rilevare anomalie e aumentare l'affidabilità. Come ulteriore contributo, la tesi discute le questioni etiche legate alla blockchain. Viene proposto un modello quantitativo di valutazione del richio etico, al fine di valutare le applicazioni basate su blockchain e garantire la loro coerenza con i pilastri etici e della privacy. In sintesi, questa tesi si propone di analizzare come la blockchain potrebbe essere utilizzata per aumentare la fiducia all'interno di sistemi digitali. Gli approcci e le tecniche studiate contribuiscono a migliorare lo sviluppo di ecosistemi digitali sicuri, efficienti ed eticamente validi. Nowadays, the increasing digitization generates an huge amount of data that represent an extremely important asset. However, ensuring the integrity and certification of such data, as well as the authenticity of their source, appears to be a crucial challenge. In fact, digital identities, data, and processes should be secure and reliable to ensure privacy, transparency, and trust among users. Blockchain technology arises as a strong method to ensure trust among a set of untrusted users. In fact, the blockchain distributed nature, thanks to cryptographic functions and to an underlying consensus protocol, ensures immutable records without the need of a central authority. Blockchain technology was first introduced by Satoshi Nakamoto in 2008 for creating a decentralized cash system, but, thanks to its properties, it is now used for several applications. We argue that also the certification of digital identities and data may benefit from blockchain technology. In fact, its properties, such as decentralization, immutability, and transparency, offer an innovative way to handle such issues. This thesis explores new blockchain-based methods for handling digital identity, data certification, and traceability, while analyzing the inherent risks and proposing solutions for their mitigation. We propose two different methods for certifying traceability data, which can be applied according to different scenarios. These approaches illustrate how blockchain can be applied for data certification and verification, while paying particular attention to ensure personal data protection, as requested by national and international regulations. Therefore, the proposed approaches find applications in academic credentialing, supply chain management, and proof-of-attendance systems. Then, we focus in the integration of embedded devices directly with blockchain networks to allow for automated tamper-proof data acquisition and certification. This way, the absence of intermediaries ensures the authenticity of data, beside their integrity. To increase the trustworthiness of data, it is very important to authenticate data sources, which can be both users and objects/devices. We first propose a biometric authentication system integrated with blockchain, which enhances security and removes vulnerabilities associated with the centralized storage of sensitive data. Then, we propose a new blockchain consensus mechanism that ensures, at the same time, fuzzy sources authentication and consensus over the network. Beside the advantages of blockchain application for digital identity, data traceability and certification, it is crucial to also evaluate associated risks. We analyze some hidden risks, such as data availability attacks, when malicious nodes withhold critical parts of a block from being validated. We propose an optimized version of a protocol facing these attacks, by enabling light nodes to randomly sample data, detect anomalies, and increase reliability. As a further contribution, the thesis discusses ethical issues related to blockchain. A quantitative ethics assessment model is proposed for evaluating blockchain applications and ensuring their coherence with ethical and privacy pillars. In summary, this thesis aims to analyze how blockchain could be used for enhance trust in digital systems. The studied approaches and techniques contribute to improvement in the development of secure, efficient, and ethically sound digital ecosystems, capable of meeting the need of a data-centric world.
Ethical Biases in Machine Learning-based Filtering of Internet Communications
No full textThe use of automated systems based on artificial intelligence and machine learning for filtering and moderating online communications has become commonplace. While this allows for high levels of efficiency and fine-grained control of malicious behaviors, it could also produce unintended disparities in treatment of legitimate users. In this paper, we aim at identifying some possible field-related biases in the well-known Google Perspective API machine learning-based engine for controlling Internet communications. For this purpose, we consider communications in the fields of health, trade, finance, and defense and build a data set collecting Twitter-based online communications of the World Health Organization (WHO), World Trade Organization (WTO), International Monetary Fund (IMF) and North Atlantic Treaty Organization (NATO). Collected data are then analyzed through Perspective API to assign them an alleged likelihood of being abusive for specific emotional concepts, referred to as attributes. Upon analysis, discrimination between the considered users is identified for all attributes. This result, although preliminary, apparently indicates that Perspective API creates discrimination for field-related content as a result of semantic biases in the data, thus highlighting the need for an ethically sound design of these systems, following an ethics by design approach
A Quantitative Model for the Assessment of Ethics Risks in Information Technology
No full textThe management of sensitive and personal data in the healthcare sector must guarantee the widest respect of patients' fundamental rights. However, some quantitative evaluation framework for assessing the level of ethical compliance of a technology to the most important ethical principles is still missing. In this work, we first provide a model to quantitatively assess constitutive ethics, i.e., the intrinsic ethical compliance of a technology. Secondly, we propose a method for quantitatively assessing circumstantial ethics risks of a technology, when used in some specific context. Our ethics risk assessment model is based on the evaluation of the compliance of the technology to a defined set of controls about some ethical principles and about the robustness of the technological infrastructure underneath. Then, we validate our model by applying it to some recent healthrelated blockchain frameworks, and we compare a qualitative ethical assessment with the quantitative assessment made with the proposed model for constitutive ethics compliance. Through our assessment, we identify some technical choices that achieve the highest ethical scores, such as using a permissioned blockchain, off-chain storage, and encryption of data. Finally, we observe that the principles of privacy and data governance turn out to be the most satisfied ethical principles, contrary to fairness
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
- …
