Where Do Facts Matter? The Digital Paradox in Magazines\u27 Fact-Checking Practices

Print magazines are unique among nonfiction media in their dedication of staff and resources to in-depth, word-by-word verification of stories. Over time, this practice has established magazines’ reputation for reliability, helped them retain loyal readers amid a glut of information sources, and protected them from litigation. But during the past decade, websites, mobile platforms, and social media have expanded the types of stories and other content that magazines provide readers. Doing so has shortened the time between the creation and dissemination of content, challenging and in some cases squeezing out fact-checkers’ participation. This study examines the procedures applied to stories in magazines and their non-print platforms, seeking to discern what decisions were made in response to the speed of digital publication, what effects these decisions have had, what lessons have been learned and what changes have been made over time. The results suggest that fact-checking practices for print content remain solidly in place at most magazines, if executed with diminished resources; however, magazine media are also exploring new processes to ensure accuracy and protect their reputations in an accelerated media environment

Smart Types for Smart Contracts Validation

The notion of Smart Contracts consist in describing agreements between two or more parties that can be automatically enforced without a trusted intermediary. Smart Con- tracts run on a very specific network of peers called Blockchain, a a digitally distributed, decentralized, public ledger that exists across a network. Potential conflicts are resolved by the network’s consensus protocol. The Blockchain [26] is immutable, this means that once a Smart Contract is deployed on the Blockchain it cannot be amended. This immutability (despite being one important selling point of Smart Contracts) leave no room for mistakes in their implementation. Many contracts are hard to implement correctly and bugs and vulnerabilities can be exploited for erroneous or even fraudulent behaviour. The countless advantages and applications of Smart contracts are constantly increas- ing their popularity. This added to the fact that Smart Contracts manipulate resources with monetary value is bringing a lot of attention to attackers. There are a lot of infamous Smart Contracts attacks, the DAO Attack per example drained millions of dollars in Ether (cryptocurrency of Ethereum). Mainstream tools used to develop distributed Smart Contracts do not address these requirements. Consequently, many vulnerabilities of these contracts are known and can be exploited. In order to help developers to design safer contracts that follow their protocols and specifications we propose a language integrated with assertions and a static behavioural type system able of protecting resources and enforce usage protocols to ensure the safety and soundness in Smart Contracts execution. Since proof assistants are too demanding for most developers, there is a need for automatic tools well integrated with programming languages. Therefore, we joined our language with a model-checker to discharge to it the quantitative assertions during the compilation process. In short, we provided a translation of the types and assertions to an automaton in the format of Cubicle’s (model checker) input language and used this one to conduct Software Verification

PLACES'10: The 3rd Workshop on Programmng Language Approaches to concurrency and Communication-Centric Software

Paphos, Cyprus. March 201

Early validation of system requirements and design

Dissertação de mestrado em Engenharia InformáticaModern society is relying more and more on electronic devices, most of which are em bedded systems and are sometimes responsible for performing safety-critical tasks. As the complexity of such systems increases due to concurrency concerns and real-time con straints, their design is more prone to errors which can lead to catastrophic outcomes. In order to reduce the risk of such outcomes, a model-based methodology is commonly used. The model describes the behaviour of the system and is subject to verification tech niques such as simulation and model checking in order to verify it behaves according to the requirements. Common problems that arise with this methodology is the ambiguity of requirements written in natural language and the translation of a requirement to a property that can be verified along with the model. This thesis proposes a tool that, after the translation of the requirements to temporal formalism, allows the automatic generation of monitors in order to verify the model. Our target platform is Simulink, which is widely used in this domain to model, simulate and analyze dynamic systems.A sociedade de hoje depende cada vez mais de dispositivos eletrónicos, a maioria dos quais são sistemas embebidos e, por vezes, responsáveis pela realização de tarefas críticas. À medida que a complexidade destes sistemas aumenta devido a problemas de concorrência ou restrições de tempo real, o design torna-se mais suscetível a erros que podem levar a resultados catastróficos. A fim de reduzir estes riscos, recorre-se a uma metodologia de desenvolvimento baseada em modelos. O modelo descreve o comportamento do sistema e pode ser sujeito a técnicas de verificação, tais como simulação ou model checking, a fim de verificar que este exibe o comportamento descrito nos requisitos. Problemas comuns que surgem com esta metodologia devem-se a ambiguidade dos requisitos, tipicamente escritos em linguagem natural, e a tradução destes para uma propriedade que pode ser verificada em conjunto com o modelo. Esta dissertação propõe uma ferramenta que, após a tradução dos requisitos para uma linguagem de especificação formal, permite a geração automática de monitores para verificar o modelo. A plataforma para a qual os monitores são gerados e o Simulink, que é tipicamente utilizado neste domínio para modelar, simular e analisar sistemas dinâmicos