3,140 research outputs found
CEPS Task Force on Artificial Intelligence and Cybersecurity Technology, Governance and Policy Challenges Task Force Evaluation of the HLEG Trustworthy AI Assessment List (Pilot Version). CEPS Task Force Report 22 January 2020
The Centre for European Policy Studies launched a Task Force on Artificial Intelligence (AI) and
Cybersecurity in September 2019. The goal of this Task Force is to bring attention to the market,
technical, ethical and governance challenges posed by the intersection of AI and cybersecurity,
focusing both on AI for cybersecurity but also cybersecurity for AI. The Task Force is multi-stakeholder
by design and composed of academics, industry players from various sectors, policymakers and civil
society.
The Task Force is currently discussing issues such as the state and evolution of the application of AI
in cybersecurity and cybersecurity for AI; the debate on the role that AI could play in the dynamics
between cyber attackers and defenders; the increasing need for sharing information on threats and
how to deal with the vulnerabilities of AI-enabled systems; options for policy experimentation; and
possible EU policy measures to ease the adoption of AI in cybersecurity in Europe.
As part of such activities, this report aims at assessing the High-Level Expert Group (HLEG) on AI Ethics
Guidelines for Trustworthy AI, presented on April 8, 2019. In particular, this report analyses and
makes suggestions on the Trustworthy AI Assessment List (Pilot version), a non-exhaustive list aimed
at helping the public and the private sector in operationalising Trustworthy AI. The list is composed
of 131 items that are supposed to guide AI designers and developers throughout the process of
design, development, and deployment of AI, although not intended as guidance to ensure
compliance with the applicable laws. The list is in its piloting phase and is currently undergoing a
revision that will be finalised in early 2020.
This report would like to contribute to this revision by addressing in particular the interplay between
AI and cybersecurity. This evaluation has been made according to specific criteria: whether and how
the items of the Assessment List refer to existing legislation (e.g. GDPR, EU Charter of Fundamental
Rights); whether they refer to moral principles (but not laws); whether they consider that AI attacks
are fundamentally different from traditional cyberattacks; whether they are compatible with
different risk levels; whether they are flexible enough in terms of clear/easy measurement,
implementation by AI developers and SMEs; and overall, whether they are likely to create obstacles
for the industry.
The HLEG is a diverse group, with more than 50 members representing different stakeholders, such
as think tanks, academia, EU Agencies, civil society, and industry, who were given the difficult task of
producing a simple checklist for a complex issue. The public engagement exercise looks successful
overall in that more than 450 stakeholders have signed in and are contributing to the process.
The next sections of this report present the items listed by the HLEG followed by the analysis and
suggestions raised by the Task Force (see list of the members of the Task Force in Annex 1)
Estimulação diafragmática no rato anestesiado: um novo modelo de pacing respiratório
Relatório de projecto no âmbito de Bolsa Universidade de Lisboa/Fundação Amadeu Dias (2010/2011). Universidade de Lisboa. Faculdade de MedicinaO presente projecto inclui-se no projecto de construção de um pacing diafragmático fisiológico e dinâmico, implantável no diafragma. O objectivo especÃfico deste trabalho consiste na monitorização, em modelo animal, de variações da actividade do frénico, variando a frequência de ciclos respiratórios através de respiração artificial de ar ambiente enriquecido em O2. Estes resultados possibilitarão a construção de um pacing respiratório dinâmico que mimetisa, de forma artificial, o quimiorreflexo humano, responsável pela regulação da respiração
Massive MIMO transmission techniques
Next generation of mobile communication systems must support astounding data traffic increases, higher data rates and lower latency, among other requirements. These requirements should be met while assuring energy efficiency for mobile devices and base stations.
Several technologies are being proposed for 5G, but a consensus begins to emerge. Most likely, the future core 5G technologies will include massive MIMO (Multiple Input Multiple Output) and beamforming schemes operating in the millimeter wave spectrum. As soon as the millimeter wave propagation difficulties are overcome, the full potential of massive MIMO structures can be tapped.
The present work proposes a new transmission system with bi-dimensional antenna arrays working at millimeter wave frequencies, where the multiple antenna configurations can be used to obtain very high gain and directive transmission in point to point communications. A combination of beamforming with a constellation shaping scheme is proposed, that enables good user isolation and protection against eavesdropping, while simultaneously assuring power efficient amplification of multi-level constellations
Petri nets based components within globally asynchronous locally synchronous systems
Dissertação apresentada na Faculdade de Ciências e Tecnologias da Universidade Nova de Lisboa para a obtenção do grau de Mestre em Engenharia Electrotécnica e ComputadoresThe main goal is to develop a solution for the interconnection of components constituent of a GALS - Globally Asynchronous, Locally Synchronous – system. The components are implemented in parallel obtained as a result of the partition of a model expressed a Petri net (PN), performed using the PNs editor SNOOPY-IOPT in conjunction with the Split tool and the tools to automatically generate the VHDL code from the representations of the PNML models resulting from the partition (these tools were developed under the project FORDESIGN and are available at http://www.uninova.pt/FORDESIGN). Typical solutions will be analyzed to ensure proper communication between components of the GALS system, as well as characterized and developed an appropriate solution for the interconnection of the components associated with the PN sub-models. The final goal (not attained with this thesis) would be to acquire a tool that allows generation of code for the interconnection solution from the associated components, considering a specific application. The solution proposed for componentes interconnection was coded in VHDL and the implementation platforms used for testing include the Xilinx FPGA Spartan-3 and Virtex-II
A Note on Models, Algorithms, and Data Structures for Dynamic Communication Networks
New technologies and the deployment of mobile and nomadic services are driving the emergence of complex communications networks, that have a highly dynamic behavior. Modeling such dynamics, and designing algorithms that take it into account, received considerable attention recently. In this note, we discuss a formal generalization of dynamic graphs, the evolving graphs, which aims at harnessing the complexity of an evolving setting as yielded by dynamic communication networks. We argue that evolving graphs are of great help when dealing with fixed-schedule networks. Moreover, we show how to exploit our model with networks where short time prediction is available
Perylene Diimide acceptors: Fabrication and characterization of electron-only, hole-only devices and solar cells
The thrust towards energy conservation and reduced environmental footprint has fueled intensive
research for alternative low cost sources of renewable energy. Organic photovoltaic cells (OPVs), with their low fabrication costs, easy processing and flexibility, represent a possible viable alternative. Perylene diimides (PDIs) are promising electron-acceptor candidates for bulk heterojunction (BHJ) OPVs, as they combine higher absorption and stability with tunable material properties, such as solubility and position of the lowest unoccupied molecular orbital (LUMO) level. A prerequisite for trap free electron transport is for the LUMO to be located at a level deeper than 3.7 eV since electron trapping in organic semiconductors is universal and dominated by a trap level located at 3.6 eV. Although the mostly used fullerene acceptors in polymer:fullerene solar cells feature trap-free electron transport, low optical absorption of fullerene derivatives limits maximum attainable efficiency. In this thesis, we try to get a better understanding of the electronic properties of PDIs, with a focus on charge carrier transport characteristics and the effect of different processing conditions such as annealing temperature and top contact (cathode) material. We report on a commercially available PDI and three PDI derivatives as acceptor materials, and its blends with MEH-PPV (Poly[2-methoxy 5-(2-ethylhexyloxy)-1,4-phenylenevinylene]) and P3HT (Poly(3-hexylthiophene-2,5-diyl)) donor materials in single carrier devices (electron-only and hole-only) and in solar cells. Space-charge limited current measurements and modelling of temperature dependent J-V characteristics confirmed that the electron transport is essentially trap-free in such materials. Different blend ratios of P3HT:PDI-1 (1:1) and (1:3) show increase in the device performance with increasing PDI-1 ratio. Furthermore, thermal annealing of the devices have a significant effect in the solar cells that decreases open-circuit voltage (Voc) and fill factor FF, but increases short-circuit current (Jsc) and overall device performance. Morphological studies show that over-aggregation in traditional donor:PDI blend systems is still a big problem, which hinders charge carrier transport and performance in solar cells
Oil prices and unemployment: empirical evidence from Brazil
In this study we present empirical evidence for the existence of a long-run relation between the rate of unemployment in Brazil and the price of energy plus the real interest rate. After establishing the existence of cointegration among those variables, we estimate the long-run coefficients relating the real interest rate and the real price of oil to the rate of unemployment. Our results show that a doubling of the price of oil tends to bring about an absolute increase of 1.6 percentage points in the unemployment rate
Second Life : representation and remediation of social space
Ao longo da última década os jogos online e as plataformas sociais têm-se tornado cada vez mais populares, tendo vindo a contribuir para o desenvolvimento da internet. Os jogos online multiplayer têm conquistado cada vez mais utilizadores. Estes têm como locus a realidade virtual e como objetivo a recriação de um novo mundo. Um exemplo deste tipo de jogos é o Second Life, um jogo social que conta com um elevado número de utilizadores – cerca de 31 milhões de utilizadores registados. Esta plataforma foi desenvolvida pela Linden Lab e reúne as caracterÃsticas de um mundo virtual: é um cenário digital tridimensional, no qual utilizadores de todo o mundo, representados por avatares, interagem em tempo real formando diversos tipos de redes sociais. Uma das suas caracterÃsticas distintivas é o facto de 99% do conteúdo existente dentro do espaço virtual ter sido desenvolvido pelos utilizadores. Os jogadores, denominados residentes, estão a contribuir não só na construção do espaço, mas também para o desenvolvimento social deste mundo virtual. Para além disto, existem mais quatro caracterÃsticas que tornam o Second Life um objeto de estudo interessante: todos os avatares são controlados por seres humanos em tempo real; o reconhecimento de direitos de propriedade intelectual; a existência de uma micro-moeda – o Linden Dollar; e o facto de todos os jogadores terem acesso a ferramentas básicas de construção, e à linguagem de programação desenvolvida pela Linden Lab, a Linden Scripting Language, essenciais para criar objetos.
O Second Life é um espaço colaborativo e participativo que, apesar de ser um jogo, oferece aos seus utilizadores uma experiência muito diferente da vivida nos videojogos tradicionais. Por ser um jogo do tipo caixa de areia os jogadores podem estabelecer uma relação diferente com esta plataforma, pois podem contribuir para as diversas dimensões da vida dentro do jogo. Devido à s suas caracterÃsticas, este mundo virtual tem despertado o interesse de investigadores de diferentes áreas que têm procurado perceber o seu impacto para a interação social, educação, economia, lei, e indústrias criativas. No entanto, tendo em conta que o ‘espaço’ é um elemento fulcral na investigação em Ciências Humanas e uma das áreas priveligiadas pela European Science Foundation para a investigação em Ciências Sociais e Humanas, há, ainda, a necessidade de perceber como é que este espaço digital está a ser desenvolvido, e que narrativas culturais o estão a moldar. Uma vez que o Second Life reflete a importância dos mundos virtuais para a interação online, torna-se fundamental compreender que impacto a virtualização das relações sociais pode ter para a interação interpessoal e para o desenvolvimento de um novo tipo de ‘comunidades imaginadas’.
A presente investigação centra-se no Second Life e procura perceber de que forma poderá este novo espaço de interação estar a contribuir para o aparecimento de uma nova dimensão social. Uma dimensão resultante das possibilidades oferecidas por uma plataforma tecnológica apenas disponÃvel através da internet, combinadas com o potencial criativo dos seus utilizadores. Com o intuito de contribuir para um melhor entendimento do potencial sociocultural deste mundo virtual, este estudo tem como base uma investigação empÃrica desenvolvida a partir de uma metodologia qualitativa especÃfica para o estudo de comunidades online, a netnografia. Os métodos de recolha de dados adotados são: observação participante, auto-netnografia, entrevista e análise de conteúdo dos perfis dos utilizadores entrevistados. Os dados são analisados seguindo uma abordagem indutiva.
A principal hipótese deste estudo centra-se na premissa que se o Second Life é um mundo virtual que está a ser coproduzido pela Linden Lab e pelos utilizadores, é provável que o envolvimento dos residentes com a realidade virtual resulte na criação de um sistema de representação re-mediado. Partindo desta hipótese, os objetivos principais desta investigação são confirmar se de facto os mundos virtuais estão a ser usados para representar e re-mediar o espaço social, e perceber que efeito isto tem nos jogadores. Uma das principais conclusões retiradas prende-se com o facto de os utilizadores estarem a tirar partido deste mundo virtual para renegociarem os modelos socioculturais que informam as suas ‘primeiras vidas’. Após a análise da relação que os utilizadores estabelecem com o espaço virtual, com os seus próprios avatares e entre si, concluiu-se que são três as principais narrativas culturais que estão a resultar das experiências vividas pelos residentes deste mundo virtual. As primeiras intrinsecamente relacionadas com a organização geográfica da vida humana – narrativas de espaço; as segundas, com a necessidade de nos compreendermos a nós mesmos, narrativas identitárias; e as terceiras, com o facto de os seres humanos serem na sua essência seres sociais, narrativas resultantes da interação social com outros residentes. A ‘re-mediação’ de narrativas culturais dentro de um ambiente online, anónimo e flexÃvel evidencia a necessidade que os seres humanos têm de reconhecer os espaços sociais que frequentam, de modo a envolverem-se e atribuÃrem significado à s experiências digitais vividas.Over the past decade online games and social platforms became very popular and contributed to the internet development. The massive multiplayer online games have conquered a high number of users. The locus of these games is virtual reality, and the main goal is the recreation of a new world. Second Life is one of these games, a tridimensional social platform which counts with a high number of users – around 31 million registered users. It was developed by Linden Lab and it assembles the main characteristics of a virtual worlds: it is a tridimensional digital setting where users from all over the world represented by avatars interact in real time, and develop diversified social networks. One of its main characteristics is the prevalence of prodused content – 99 per cent of the content existing in-world was created by residents. Players, designated residents, are not only contributing to the space construction, but also to the social development of this virtual world. Apart from this, there are four more characteristics that make this multiuser environment interesting as an object of study: all the avatars existent in-world are playing characters controlled by human beings in real time; the recognition of intellectual property rights; the existence of a micro-currency – the Linden Dollar; and all the players have access to simple building tools, and to the Linden Scripting Language, which are essential to create objects.
Second Life is a collaborative and participative space that, despite being a game, offers its users a very different experience from that lived within traditional video games. Because it is a sandbox game players are able to establish a different kind of relationship with the platform, once they can contribute to the different dimensions of the life in-world. Due to its intrinsic characteristics, this virtual world has caught the attention of researchers from several areas that showed interest in understanding the impact this virtual world may have in social interaction, education, economy, law and creative industries. Notwithstanding, considering that ‘space’ is a key element in the Humanities, and one of the privileged areas by the European Science Foundation for the research in Social Sciences and Humanities, it is necessary to better understand how this digital space is being developed, and which cultural narratives are shaping it. Since Second Life reflects the relevance of virtual worlds to online interaction, it is essential to comprehend the impact that the ‘virtualization’ of social relationships may have for interpersonal interaction, and for the emergence of a new type of ‘imagined communities’.
The present research is centered on Second Life and looks forward to understand how this new interaction space could be contributing to the emergence of a new social dimension. A dimension resulting from the possibilities offered by a technology platform only available through the internet, combined with the creative potential of its users. In order to contribute to a better understanding of the sociocultural potential of this virtual world, this study is grounded on an empirical research based on a specific qualitative methodology for studying online communities, the netnography. The methods adopted for data collection are: participant observation, auto-netnography, interview, and content analysis of the interviewees’ profiles. The data collected is analyzed through an inductive approach.
The main hypothesis framing this research is the premise that if Second Life is a virtual world that is being prodused by its residents, it is probable that users’ involvement with the virtual reality would result in the creation of a remediated system of representation. Based on this hypothesis, the main goals then are to confirm if virtual worlds are indeed representing and remediating social space, and to understand the effect this has on players. One of the main conclusions reached is that the users are taking advantage of the affordances of this virtual world to renegotiate the sociocultural models that frame their first lives. Through the analysis of the relationship users are establishing with the virtual space, with their own avatars, and with each other, it is concluded that there are three main cultural narratives emerging from the in-world experience lived by the residents. The first intrinsically related with the geographical organization of human life – spatial narratives; the second, with the need to make sense of oneself – narratives of identity; and the third, with the fact that humans are social beings in essence – social interaction narratives resulting from the interaction with other residents. The remediation of cultural narratives into an online, anonymous, and flexible environment evinces the need humans have for recognizable social spaces in order to be able to get involved and attribute meaning to the lived digital experiences
A multi-sector growth model with technology diffusion and networks
This paper adds the standard input–output linkages into a multi-sector endogenous growth model to study the interaction effects between linkages and technology adoption for aggregate productivity and for income per capita. We show that the greater the intensity with which a good is used as input by other sectors, the smaller are the technology adoption lags and the greater is the technology adoption intensity, and thus the greater are the increases of the Total Factor Productivity and of economic growth. Therefore, distinct input–output relationships between sectors explain inter-country income differences. By using OECD data, we then estimate the model for nine developed countries and ten technologies, and confirm our theoretical findings.Financial support from Spanish Ministerio de EconomÃa y Competitividad and Fondo Europeo de Desarrollo Regional through the grants ECO2013-43119-P, ECO2015-70540-P and ECO2016-77200-P (MINECO/FEDER) is gratefully acknowledged
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