Introducing Financial Derivatives into Football Transfer Markets

Εθνικό Μετσόβιο Πολυτεχνείο--Μεταπτυχιακή Εργασία. Διεπιστημονικό-Διατμηματικό Πρόγραμμα Μεταπτυχιακών Σπουδών (Δ.Π.Μ.Σ.) “Μαθηματική Προτυποποίηση σε Σύγχρονες Τεχνολογίες και στα Χρηματοοικονομικά

The echoes of grassroots media practices in Greece: a sociological approach

This thesis probes into grassroots media projects by addressing them in a broad theoretical framework that evaluates such projects in macro terms, along the interplay between 'public sphere' and 'civil society', as well as in micro terms, across the 'lived experience' of their practice, on the grounds of the expression and enactment of 'citizenship' correspondingly. From this perspective, the study researches media projects that are implemented `on the margins' in Greece, drawing both on their contribution to and intervention in the public and political life. By evaluating these projects in a resonant context the study prioritizes the 'agents', citizens/social groups, who are engaged in their practice. Using empirical evidence from fieldwork conducted in Greece in 2003 involving: indepth interviews with people engaged (forty four participants) in the practice of diverse, heterogeneous media projects - one newspaper, two periodicals, three pirate radio stations and three Internet sites - this thesis evaluates the limits and the challenges of the practice of such projects in terms of their contribution to the public sphere and their intervention in the sphere of 'the political'. It argues that while such projects constitute a realm for the representation of various social domains, collectives/social groups and their discourses, as well as, for their intervention in civic life, at the same time their practice is entrapped in traditional 'politics' that deter the expansion of these projects, and negate the potential their practice encompasses for the constitution of `the political' in the realm of everyday life as well

Prosody and intrasyllabic timing in French

Durational variation associated with accentuation and final lengthening is examined in a corpus of articulatory data for French. Both factors are associated with measurable differences in acoustic duration. However two different articulatory strategies are employed to make these contrasts although both result in superficially longer and more displaced gestures.Parts of this research were supported by the National Science Foundation (USA) under Grant no. IRI-8858109 to Mary Beckman, the Ohio State University, and by the National Institutes of Health (USA) under Grant no. NS-13617 to Haskins Laboratories

Weighted tardiness minimization for unrelated machines with sequence-dependent and resource-constrained setups

Motivated by the need of quick job (re-)scheduling, we examine an elaborate scheduling environment under the objective of total weighted tardiness minimization. The examined problem variant moves well beyond existing literature, as it considers unrelated machines, sequence-dependent and machine-dependent setup times and a renewable resource constraint on the number of simultaneous setups. For this variant, we provide a relaxed MILP to calculate lower bounds, thus estimating a worst-case optimality gap. As a fast exact approach appears not plausible for instances of practical importance, we extend known (meta-)heuristics to deal with the problem at hand, coupling them with a Constraint Programming (CP) component - vital to guarantee the non-violation of the problem's constraints - which optimally allocates resources with respect to tardiness minimization. The validity and versatility of employing different (meta-)heuristics exploiting a relaxed MILP as a quality measure is revealed by our extensive experimental study, which shows that the methods deployed have complementary strengths depending on the instance parameters. Since the problem description has been obtained from a textile manufacturer where jobs of diverse size arrive continuously under tight deadlines, we also discuss the practical impact of our approach in terms of both tardiness decrease and broader managerial insights

The echoes of grassroots media practices in Greece : a sociological approach

This thesis probes into grassroots media projects by addressing them in a broad theoretical framework that evaluates such projects in macro terms, along the interplay between 'public sphere' and 'civil society', as well as in micro terms, across the 'lived experience' of their practice, on the grounds of the expression and enactment of 'citizenship' correspondingly. From this perspective, the study researches media projects that are implemented `on the margins' in Greece, drawing both on their contribution to and intervention in the public and political life. By evaluating these projects in a resonant context the study prioritizes the 'agents', citizens/social groups, who are engaged in their practice. Using empirical evidence from fieldwork conducted in Greece in 2003 involving: indepth interviews with people engaged (forty four participants) in the practice of diverse, heterogeneous media projects - one newspaper, two periodicals, three pirate radio stations and three Internet sites - this thesis evaluates the limits and the challenges of the practice of such projects in terms of their contribution to the public sphere and their intervention in the sphere of 'the political'. It argues that while such projects constitute a realm for the representation of various social domains, collectives/social groups and their discourses, as well as, for their intervention in civic life, at the same time their practice is entrapped in traditional 'politics' that deter the expansion of these projects, and negate the potential their practice encompasses for the constitution of `the political' in the realm of everyday life as well.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Multisensory Integration Sites Identified by Perception of Spatial Wavelet Filtered Visual Speech Gesture Information

Perception of speech is improved when presentation of the audio signal is accompanied by concordant visual speech gesture information. This enhancement is most prevalent when the audio signal is degraded. One potential means by which the brain affords perceptual enhancement is thought to be through the integration of concordant information from multiple sensory channels in a common site of convergence, multisensory integration (MSI) sites. Some studies have identified potential sites in the superior temporal gyrus/sulcus (STG/S) that are responsive to multisensory information from the auditory speech signal and visual speech movement. One limitation of these studies is that they do not control for activity resulting from attentional modulation cued by such things as visual information signaling the onsets and offsets of the acoustic speech signal, as well as activity resulting from MSI of properties of the auditory speech signal with aspects of gross visual motion that are not specific to place of articulation information. This fMRI experiment uses spatial wavelet bandpass filtered Japanese sentences presented with background multispeaker audio noise to discern brain activity reflecting MSI induced by auditory and visual correspondence of place of articulation information that controls for activity resulting from the above-mentioned factors. The experiment consists of a low-frequency (LF) filtered condition containing gross visual motion of the lips, jaw, and head without specific place of articulation information, a midfrequency (MF) filtered condition containing place of articulation information, and an unfiltered (UF) condition. Sites of MSI selectively induced by auditory and visual correspondence of place of articulation information were determined by the presence of activity for both the MF and UF conditions relative to the LF condition. Based on these criteria, sites of MSI were found predominantly in the left middle temporal gyrus (MTG), and the left STG/S (including the auditory cortex). By controlling for additional factors that could also induce greater activity resulting from visual motion information, this study identifies potential MSI sites that we believe are involved with improved speech perception intelligibility

One Benders cut to rule all schedules in the neighbourhood

Logic-Based Benders Decomposition (LBBD) and its Branch-and-Cut variant, namely Branch-and-Check, enjoy an extensive applicability on a broad variety of problems, including scheduling. Although LBBD offers problem-specific cuts to impose tighter dual bounds, its application to resource-constrained scheduling remains less explored. Given a position-based Mixed-Integer Linear Programming (MILP) formulation for scheduling on unrelated parallel machines, we notice that certain $k-$OPT neighbourhoods could implicitly be explored by regular local search operators, thus allowing us to integrate Local Branching into Branch-and-Check schemes. After enumerating such neighbourhoods and obtaining their local optima - hence, proving that they are suboptimal - a local branching cut (applied as a Benders cut) eliminates all their solutions at once, thus avoiding an overload of the master problem with thousands of Benders cuts. However, to guarantee convergence to optimality, the constructed neighbourhood should be exhaustively explored, hence this time-consuming procedure must be accelerated by domination rules or selectively implemented on nodes which are more likely to reduce the optimality gap. In this study, the realisation of this idea is limited on the common 'internal (job) swaps' to construct formulation-specific $4$-OPT neighbourhoods. Nonetheless, the experimentation on two challenging scheduling problems (i.e., the minimisation of total completion times and the minimisation of total tardiness on unrelated machines with sequence-dependent and resource-constrained setups) shows that the proposed methodology offers considerable reductions of optimality gaps or faster convergence to optimality. The simplicity of our approach allows its transferability to other neighbourhoods and different sequencing optimisation problems, hence providing a promising prospect to improve Branch-and-Check methods

Networking activism: implications for Greece

The outbreak of December 2008 against police brutality through a wave of demonstrations and street protests in Athens, which was strongly advocated by protest activities and practices across the world, addresses several issues in relation to the transformative potentials of mediated collective action. The paper critically evaluates different accounts of December events, probing then into thevery networking of that movement. From this perspective, it points out another aspect of the local-global interplay in protest culture along new mediating practices (beyond the creation of transnational publics), that of the implications of transnational networking for local social activism and identification, addressing relevant questions in the Greek context

Constructing Silence: Processes of Journalistic (Self-)Censorship during Memoranda in Greece, Cyprus, and Spain

What are to be considered as threats against journalism? Whereas the literature on safety of journalists mainly discusses threats as part of armed conflicts, this article studies how other kinds of conflicts such as economic strangulation and the viability threat represent threats against journalists’ work and safety. It argues that acts of intimidation directed against journalists represent an attack on democracy itself as they have the effect of limiting the freedom of expression. The aim of this study is to explore how journalists operate in such a conflict and under such uncertainty, as an implication of (political) pressure caused by the politics of Memoranda in Greece, Cyprus, and Spain. The comparative analysis focuses on possible changes in the processes of message construction and in the journalistic practices of the participants, exploring if, how, and to what extent these changes were imposed to journalists directly or indirectly