194 research outputs found

    Spartan Daily, April 20, 2017

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    Volume 148, Issue 34https://scholarworks.sjsu.edu/spartan_daily_2017/1032/thumbnail.jp

    Spartan Daily, February 7, 1991

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    Volume 96, Issue 7https://scholarworks.sjsu.edu/spartandaily/8075/thumbnail.jp

    Spartan Daily, February 7, 1991

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    Volume 96, Issue 7https://scholarworks.sjsu.edu/spartandaily/8075/thumbnail.jp

    Análise de propriedades intrínsecas e extrínsecas de amostras biométricas para detecção de ataques de apresentação

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    Orientadores: Anderson de Rezende Rocha, Hélio PedriniTese (doutorado) - Universidade Estadual de Campinas, Instituto de ComputaçãoResumo: Os recentes avanços nas áreas de pesquisa em biometria, forense e segurança da informação trouxeram importantes melhorias na eficácia dos sistemas de reconhecimento biométricos. No entanto, um desafio ainda em aberto é a vulnerabilidade de tais sistemas contra ataques de apresentação, nos quais os usuários impostores criam amostras sintéticas, a partir das informações biométricas originais de um usuário legítimo, e as apresentam ao sensor de aquisição procurando se autenticar como um usuário válido. Dependendo da modalidade biométrica, os tipos de ataque variam de acordo com o tipo de material usado para construir as amostras sintéticas. Por exemplo, em biometria facial, uma tentativa de ataque é caracterizada quando um usuário impostor apresenta ao sensor de aquisição uma fotografia, um vídeo digital ou uma máscara 3D com as informações faciais de um usuário-alvo. Em sistemas de biometria baseados em íris, os ataques de apresentação podem ser realizados com fotografias impressas ou com lentes de contato contendo os padrões de íris de um usuário-alvo ou mesmo padrões de textura sintéticas. Nos sistemas biométricos de impressão digital, os usuários impostores podem enganar o sensor biométrico usando réplicas dos padrões de impressão digital construídas com materiais sintéticos, como látex, massa de modelar, silicone, entre outros. Esta pesquisa teve como objetivo o desenvolvimento de soluções para detecção de ataques de apresentação considerando os sistemas biométricos faciais, de íris e de impressão digital. As linhas de investigação apresentadas nesta tese incluem o desenvolvimento de representações baseadas nas informações espaciais, temporais e espectrais da assinatura de ruído; em propriedades intrínsecas das amostras biométricas (e.g., mapas de albedo, de reflectância e de profundidade) e em técnicas de aprendizagem supervisionada de características. Os principais resultados e contribuições apresentadas nesta tese incluem: a criação de um grande conjunto de dados publicamente disponível contendo aproximadamente 17K videos de simulações de ataques de apresentações e de acessos genuínos em um sistema biométrico facial, os quais foram coletados com a autorização do Comitê de Ética em Pesquisa da Unicamp; o desenvolvimento de novas abordagens para modelagem e análise de propriedades extrínsecas das amostras biométricas relacionadas aos artefatos que são adicionados durante a fabricação das amostras sintéticas e sua captura pelo sensor de aquisição, cujos resultados de desempenho foram superiores a diversos métodos propostos na literature que se utilizam de métodos tradicionais de análise de images (e.g., análise de textura); a investigação de uma abordagem baseada na análise de propriedades intrínsecas das faces, estimadas a partir da informação de sombras presentes em sua superfície; e, por fim, a investigação de diferentes abordagens baseadas em redes neurais convolucionais para o aprendizado automático de características relacionadas ao nosso problema, cujos resultados foram superiores ou competitivos aos métodos considerados estado da arte para as diferentes modalidades biométricas consideradas nesta tese. A pesquisa também considerou o projeto de eficientes redes neurais com arquiteturas rasas capazes de aprender características relacionadas ao nosso problema a partir de pequenos conjuntos de dados disponíveis para o desenvolvimento e a avaliação de soluções para a detecção de ataques de apresentaçãoAbstract: Recent advances in biometrics, information forensics, and security have improved the recognition effectiveness of biometric systems. However, an ever-growing challenge is the vulnerability of such systems against presentation attacks, in which impostor users create synthetic samples from the original biometric information of a legitimate user and show them to the acquisition sensor seeking to authenticate themselves as legitimate users. Depending on the trait used by the biometric authentication, the attack types vary with the type of material used to build the synthetic samples. For instance, in facial biometric systems, an attempted attack is characterized by the type of material the impostor uses such as a photograph, a digital video, or a 3D mask with the facial information of a target user. In iris-based biometrics, presentation attacks can be accomplished with printout photographs or with contact lenses containing the iris patterns of a target user or even synthetic texture patterns. In fingerprint biometric systems, impostor users can deceive the authentication process using replicas of the fingerprint patterns built with synthetic materials such as latex, play-doh, silicone, among others. This research aimed at developing presentation attack detection (PAD) solutions whose objective is to detect attempted attacks considering different attack types, in each modality. The lines of investigation presented in this thesis aimed at devising and developing representations based on spatial, temporal and spectral information from noise signature, intrinsic properties of the biometric data (e.g., albedo, reflectance, and depth maps), and supervised feature learning techniques, taking into account different testing scenarios including cross-sensor, intra-, and inter-dataset scenarios. The main findings and contributions presented in this thesis include: the creation of a large and publicly available benchmark containing 17K videos of presentation attacks and bona-fide presentations simulations in a facial biometric system, whose collect were formally authorized by the Research Ethics Committee at Unicamp; the development of novel approaches to modeling and analysis of extrinsic properties of biometric samples related to artifacts added during the manufacturing of the synthetic samples and their capture by the acquisition sensor, whose results were superior to several approaches published in the literature that use traditional methods for image analysis (e.g., texture-based analysis); the investigation of an approach based on the analysis of intrinsic properties of faces, estimated from the information of shadows present on their surface; and the investigation of different approaches to automatically learning representations related to our problem, whose results were superior or competitive to state-of-the-art methods for the biometric modalities considered in this thesis. We also considered in this research the design of efficient neural networks with shallow architectures capable of learning characteristics related to our problem from small sets of data available to develop and evaluate PAD solutionsDoutoradoCiência da ComputaçãoDoutor em Ciência da Computação140069/2016-0 CNPq, 142110/2017-5CAPESCNP

    The George-Anne

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    Creating an Immersive and Entertaining Game for Raising Internet Privacy Awareness

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    The continuous evolution in the pervasiveness and connectedness of technology is a subject of growing concern. Databases, smartphones, tablets, laptops, wearables are all united through a single global network—the Internet. This growth has resulted in social networks and other data-collecting applications becoming a major part of life for many people. To address emerging threats and growing concerns, our goal is to present internet users with a simulation that helps them consider the actions that they take when online. To do so, we have created a narrative game, Immaculacy, which is intended to raise awareness in common privacy issues that many internet users encounter. Immaculacy is an interactive story that is set in a slightly dystopian future with a world that is littered with privacy issues. We have completed the prologue and first act of the game to serve as a demonstration for testing purposes. The demo consists of twenty- five scenes, three mini-games, and features twenty-one unique characters. Events unfold within the game based on hidden scores that are maintained throughout gameplay. In total, there are four scoring scales that we maintain: data leaking, government suspicion, character morality, and reputations with other major characters. These scores are calculated based on specific decisions made by the player both in dialogue and in interactions with the world. Throughout the narrative, we allow the player to experience many privacy issues through their explorations of a world filled with hyper surveillance and connectivity. To verify the entertainment value of Immaculacy, demonstrations and informal playtesting have been conducted in which feedback was received in improvements that can be made to the game mechanics and interface. Additionally, we are beginning formal user tests to test the educational value of the game and to further test how entertaining Immaculacy is. Ultimately, we aim to create an engaging environment which presents players with situations and choices intended to encourage them to consider their own personal behavior when using online services

    Daily Eastern News: January 22, 2020

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    https://thekeep.eiu.edu/den_2020_jan/1006/thumbnail.jp

    Daily Eastern News: January 22, 2020

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    https://thekeep.eiu.edu/den_2020_jan/1006/thumbnail.jp

    We Need to Stop Temporarily Caring: Pulse, Spoken Word Poetry, and Audience Counter-narrative Creation

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    On June 12, 2016, 49 people were killed, and 53 people were injured in a shooting at Pulse, a popular gay club in Orlando, Florida. The Pulse Nightclub shooting was the deadliest mass shooting in the United States at that time and the deadliest violent act against the LGBTQ+ community in the United States (Hancock & Haldeman, 2017; Jackson, 2017; Walter, Billard, & Murphy, 2017). The media were divided in labeling the shooting a terrorist attack or a hate crime, creating a master narrative surrounding the shooting. However, LGBTQ+ spoken word poets rejected the media’s storylines, developing counter-narratives, and instead called attention to existing violence targeting the LGBTQ+ community and promoted healing after Pulse. To better understand the connection between the Pulse Nightclub shooting, spoken word poetry, and counter-narrative creation, I conducted focus groups where individuals watched and reacted to poems about Pulse, performed by LGBTQ+ poets. Applying Braun and Clark’s (2006) thematic analysis, I hope to uncover how the counter-narratives created by the LGBTQ+ poets influence the way their audience make sense of their own experiences

    New Mexico Lobo, Volume 065, No 74, 5/3/1962

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    New Mexico Lobo, Volume 065, No 74, 5/3/1962https://digitalrepository.unm.edu/daily_lobo_1962/1039/thumbnail.jp
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