Europe in the shadow of financial crisis: Policy Making via Stance Classification

Since 2009, the European Union (EU) is phasing a multi–year financial crisis affecting the stability of its involved countries. Our goal is to gain useful insights on the societal impact of such a strong political issue through the exploitation of topic modeling and stance classification techniques. \ \ To perform this, we unravel public’s stance towards this event and empower citizens’ participation in the decision making process, taking policy’s life cycle as a baseline. The paper introduces and evaluates a bilingual stance classification architecture, enabling a deeper understanding of how citizens’ sentiment polarity changes based on the critical political decisions taken among European countries. \ \ Through three novel empirical studies, we aim to explore and answer whether stance classification can be used to: i) determine citizens’ sentiment polarity for a series of political events by observing the diversity of opinion among European citizens, ii) predict political decisions outcome made by citizens such as a referendum call, ii) examine whether citizens’ sentiments agree with governmental decisions during each stage of a policy life cycle.

Access Control in Industrial Internet of Things

The Industrial Internet of Things (IIoT) is an ecosystem that consists of - among others - various networked sensors and actuators, achieving mainly advancements related with lowering production costs and providing workflow flexibility. Introducing access control in such environments is considered to be challenging, mainly due to the variety of technologies and protocols in IIoT devices and networks. Thus, various access control models and mechanisms should be examined, as well as the additional access control requirements posed by these industrial environments. To achieve these aims, we elaborate on existing state-of-the-art access control models and architectures and investigate access control requirements in IIoT, respectively. These steps provide valuable indications on what type of an access control model and architecture may be beneficial for application in the IIoT. We describe an access control architecture capable of achieving access control in IIoT using a layered approach and based on existing virtualization concepts (e.g., the cloud). Furthermore, we provide information on the functionality of the individual access control related components, as well as where these should be placed in the overall architecture. Considering this research area to be challenging, we finally discuss open issues and anticipate these directions to provide interesting multi-disciplinary insights in both industry and academia

Cumulative notarization for long-term preservation of digital signatures

The long-term preservation of digitally signed documents may be approached and analyzed from various perspectives, i.e. future data readability, signature validity, storage media longevity, etc. The paper focuses on technology and trust issues related to the long-term validation of a digital signature. We exploit the notarization paradigm and propose a mechanism for cumulative data notarization that results in a successive trust transition towards new entities, modern technologies, and refreshed data. A future relying party will have to trust only the information provided by the last notary, in order to verify the validity of the initial signature, thus eliminating any dependency on ceased entities, obsolete data, and weak old technologies. The proposed framework uses recursive XML elements so that a notarization token structure encapsulates an identical data structure containing a previous notarization token

A Practical Steganographic Approach for Matroska based High Quality Video Files

Several steganographic algorithms have been proposed for protecting message secrecy against unauthorized “reads”. The most used method for hiding a message relies on embedding the secret message in Least Significant Bit (LSB) on the cover object. Though various digital formats have been proposed in literature to be used as cover objects, little attention has been paid on Matroska multimedia containers. In this work, we propose a practical method for applying steganography in these types of files. The proposed method consists of three distinct phases. The first one encrypts the hidden message; the second embeds it to the stego cover, while at the final step the stego cover is attached to a Matroska container. We tested our approach in various scenarios in order to evaluate the introduced overhead. Results shows that the use of several sizes for TXT and WAV files did not introduce considerable overhead. Depending on the file size the introduce overhead can be between 1 to 3 seconds.JRC.G.6-Digital Citizen Securit