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Adaptive Personality Recogntion from Text
No full textWe address the issue of domain adaptation for automatic Personality Recognition from Text (PRT).
The PRT task consists in the classification of the personality traits of some authors, given some pieces of text they wrote.
The purpose of our work is to improve current approaches to PRT in order to extract personality information from social network sites, which is a really challenging task.
We argue that current approaches, based on supervised learning, have several limitations for the adaptation to social network domain, mainly due to 1) difficulties in data annotation, 2) overfitting, 3) lack of domain adaptability and 4) multilinguality issues.
We propose and test a new approach to PRT, that we will call Adaptive Personality Recognition (APR).
We argue that this new approach solves domain adaptability problems and it is suitable for the application in Social Network Sites.
We start from an introduction that covers all the background knowledge required for understanding PRT.
It includes arguments like personality, the the Big5 factor model, the sets of correlations between language features and personality traits and a brief survey on learning approaches, that includes also feature selection and domain adaptation.
We also provide an overview of the state-of-theart in PRT and we outline the problems we see in the application of PRT to social network domain.
Basically, our APR approach is based on 1) an external model: a set of features/correlations between language and Big5 personality traits (taken from literature); 2) an adaptive strategy, that makes the model fit the distribution of the features in the dataset at hand, before generating personality hypotheses; 3) an evaluation strategy, that compares all the hypotheses generated for each single text of each author, computing confidence scores.
This allows domain adaptation, semi-supervised learning and the automatic extraction of patterns associated to personality traits, that can be added to the initial correlation set, thus combining top-down and bottom-up approaches.
The main contributions of our approach to the research in the field of PRT are: 1) the possibility to run top-down PRT from models taken from literature, adapting them to new datasets; 2) the definition of a small, language-independent and resource-free feature/ correlation set, tested on Italian and English; 3) the possibility to integrate top-down and bottom-up PRT strategies, allowing the enrichment of the initial feature/correlation from the dataset at hand; 4) the development of a system for APR, that does not require large labeled datasets for training, but just a small one for testing, minimizing the data annotation problem.
Finally, we describe some applications of APR to the analysis of personality in online social network sites, reporting results and findings.
We argue that the APR approach is very useful for Social Network Analysis, social marketing, opinion mining, sentiment analysis, mood detection and related fields
Wandering in Twilight? Democracy Promotion by the EU and the USA and Democratization in Armenia
Get PDFAlthough democracy promotion initiatives have spread around the world and supported transition, many countries have fallen back into autocracy or stalled on their way to democracy. However, the events in the Middle East and Northern Africa have revitalised the issue of democratization. On the other hand, this cry for democracy seems to be homegrown, casting doubts about the efficacy of external democracy promotion. Nevertheless, stalled and setback democracies cannot be blamed solely on the flawed strategies of democracy promoters or autocratic stubbornness of democracy targets. Similarly, labelling democracy promotion as “the grand failure” of the West is an argumentative overstretch, which lacks any practical application.
This dissertation argues that democracy can be achieved from outside, but the obstacles associated with it are more serious than anticipated by promoters. More specifically, the chances of liberal democracy being exported from outside will increase provided the utility of domestic adaptation to democracy is at least moderate, promoters are actively involved in resolution of pressing national issues, and there is no regional actor that blocks democracy and receives support for its policies from the target country.
By structurally and conceptually expanding Schimmelfennig’s international socialization framework, this study develops an analytical framework to decipher mechanisms, strategies, and subsequent outcomes of democracy promotion and democratization. While applied to Armenia, the proposed framework is a useful reference for both academics and practitioners as it provides tools for researching the outcome of democracy and democratization and provides policy recommendations. This dissertation introduces the concept of democracy blocker—a powerful authoritarian regional actor capable and willing to influence domestic policy choices of a democracy promotion target in order to block democratization. This study also makes an empirical contribution by comparing democracy promotion policies in a country that has long been neglected by the academic literature. Using process-tracing, within-case, and before-after analyses, this study compares democracy promotion policies of the EU and the USA within three different target-sectors in Armenia. The analysis of three different target-sectors of democracy promotion—elections, parties, and the media—shows democratic transformation on the macro level of a country and micro level of specific sectors.
This study argues that increased political and economic interdependence and interconnectedness of different realms within a democratizing country has led to merging of international democracy promotion and domestic democratization. In addition, the mere adoption of a law or a code of conduct does not guarantee the establishment of democracy and democratic behaviour by domestic stakeholders. Consequently, a likely upgrade of a formal democratic transformation into a behavioural one, would require democracy promoters to guarantee consistency in their efforts and follow-up on their activities, without assuming that a formally adopted rule or a completed project will necessarily assure rule-based behaviour. Thus, democracy promotion needs to be simultaneously cross-sectoral, offering material incentives for democratic transformation. Democracy promotion has the potential to not only produce numerous academic and policy analyses but also to result in a genuine democratic transformation, if promoters rationally choose their strategies and base them on existing domestic conditions
Numerical simulation of fumes evacuation in steelmaking plants
No full textEvacuation systems in steelmaking plants contribute to the security of the operators around the furnace and help to gain the emission levels stated in the environmental regulations, furthermore play a major role in the mass and heat balance of the factory. The aim of the dissertation is to study both primary and secondary emission capture systems of an electric arc furnace steelmaking plant by means of 3D computational thermal fluid dynamics calculations.
The overall performance of the post-combustion chamber, and consequently the primary line, is controlled by the size of the gap downstream the fourth hole of an electric are furnace. The impact of the opening coefficient (ratio between the gap area and the total area) on the post-combustion chamber performance has been investigated by means of a comprehensive 3D steady CFD simulation comprising radiative heat exchanges and detailed chemical reactions. It was found that there is not a unique value of the opening coefficient capable of optimizing all the relevant quantities of the evacuation process. A value of the opening coefficient in the range 0.40-0.52 appears advisable. The impact of the (mostly unknown) boundary conditions was also assessed and inefficiencies of the assumed post-combustion geometry have been highlighted.
The secondary line's capturing efficiency during the charging phase was simulated with both transient and steady-state solvers with different turbulent models, namely the standard k-e and the Large Eddy Simulation models. The results revealed that steady-state simulations provide sufficient information for designing and optimizing the geometry of the secondary capture system. The simulations also pointed out several geometries, which cause significant pressure drop and, as a result, diminish capturing ability of the canopy hood and the additional evacuation system. The boundary conditions were imposed with the help of experimental measurements in the simulated steelmaking factory
Hydrological controls on the triggering of shallow landslides: from local to landscape scale
No full textThis research tries to fill a gap between two very different scales of enquiry: the local (i.e. hillslope) scale, where detailed investigations are possible but difficult to generalize over large areas, and the landscape (i.e., catchment) scale, where representation of the physics is minimised, the resolution in space and time is maximised, and the focus is upon predicting emergent properties rather than system details. Specifically, this Thesis focused on an aspect of the geosciences that is of critical current concern: the representation of the interface between hydrological response and geomorphic processes, notable mass movements. At present there remains a great difficulty at this interface: detailed geotechnical and hydrological studies of mass movements reveal exceptionally complex interlinkages between water and the surface sediment mass, notably dynamically at the onset and during mass release; but these kinds of studies are only possible with a very detailed description of the three-dimensional structure of the porous media and its hydrological and mechanical response during (and after) rainfall events. Such analyses are feasible but tend to result in analyses that are restricted in terms of geographical generalisation. On the other hand, approaches that apply to larger spatial scales tend to over-simplify the representation of critical failure processes, such as in the assumptions that infinite slope stability analysis can be applied to failures that are finite in their slope length, or that upslope contributing area can always act as a surrogate for the hydrologic response at a point in the watershed.
The innovative element in this research lies on the assessment of rainfall-induced shallow landslide occurrence over large spatial scales, whilst accepting that shallow landslides triggering may be influenced by processes that operate over much smaller scales. Specifically, this Thesis focuses upon connection by subsurface flow pathways. New model approaches that incorporate connectivity are required to address the findings of field hydrologists. Thus, this Thesis starts from the understanding of small-scale hydrological processes to develop a large-scale topographic index-based shallow landslide model that includes the concept of subsurface hydrological connectivity.
The research aims to provide a tool for more realistic assessments of when shallow landslides may occur and where landsliding may occur at the catchment scale to support decision makers in developing more accurate land-use maps and landslide hazard mitigation plans and procedures
The High Representative for the CFSP and EU security culture: mediator or policy entrepreneur?
No full textThe High Representative for the Common Foreign and Security Policy was first established by the Amsterdam Treaty in 1999 to enhance the effectiveness and credibility of EU foreign policy. Since its creation, this body has played different roles vis-a-vis varies policy dossiers. In some cases, the High Representative has successfully coordinated the positions of Member States and enhanced the worldwide visibility of EU foreign policy. On other occasions, the High Representative played a more proactive role by identifying and operationalizing common European interests.
The varying role of the High Representative in different policy dossiers reflects the ambiguity of the EU political system. Unlike in most European states\where the executive and legislative powers are linked through the same parliamentary majority\within the EU supranational and intergovernmental sources legitimacy coexist. It is the
ambiguity deriving from it that permitted the High Representative to adopt different roles in response to different external challenges.
This research investigates the reasons that led the High Representative to play sometimes the role of mediator and at other times that of policy entrepreneur by examining the influence of security culture on EU foreign policy processes. Security culture is defined as the convergence of socially transmitted norms shared by the majority of political actors belonging to the EU security community. The norms constituting security culture concern the identification of security threats, the definition
of the appropriate instruments to deal with them, and the interaction with the international community.
The comparison of the cases of the 2001 Macedonia crisis and the negotiations over Iranfs nuclear programme reveals that shared norms.and thus the emergence of a shared culture.with regard to a given threat had an impact on policy processes
involving the High Representative. In particular, the emergence of a shared security culture created a positive context which enabled the High Representative to adopt the
role of policy entrepreneur, rather than simply mediating among Member States.
In order to address the capability-expectations gap emerged among citizens' expectations, and EUfs ability to deliver in the field of foreign policy, scholars have long stressed the need to build stronger institutions able to constrain the powers of Member States. However, this research identifies the development of a shared vision about common security as a factual pre-condition for the empowerment of central institutions and, thus, for further integration in this field. In addition, even though the existing literature has mostly identified diverging norms on the use of force in the international arena and on the alliance with the US as the major obstacles to an effective EU foreign policy, this study suggests that another major obstacle in this regard lies in diverging norms concerning the role of international cooperation and the relation between national and international security vis-a-vis external threats
The Socio-Political Economy of Antiretroviral Treatment as HIV Prevention
No full textThis doctoral thesis seeks to explore the socio-political economy of antiretroviral treatment (ART) as an HIV prevention strategy in sub-Saharan Africa (SSA) and, specifically, in Mozambique. We begin with a look at the social construction of HIV in SSA as a ‘sexually transmitted disease’ despite its very low transmission efficiency through heterosexual sex. This inordinate focus on sexual transmission in SSA to the exclusion of other routes of transmission (i.e.: blood-borne transmission) not only allows new infections to continue to occur in areas that do not receive attention, but also has both fed and been fed by a political and social climate that paints an extraordinarily negative picture of those who are infected with HIV. Alternatives to the ineffective and misguided sexual behavior prevention paradigm are introduced to conclude Chapter 1. Chapter 2 then explores, in depth, the most efficacious form of HIV prevention currently in existence: antiretroviral treatment (ART) for infected persons. ART for an infected partner is 96% effective at preventing transmission of HIV to an uninfected partner. Due to this startlingly high efficacy and recent increases in coverage, we may be preventing more new cases of HIV annually through ART than through the use of condoms and abstinence combined in Mozambique. The financial implications of a paradigmatic shift to explicitly considering ART as a prevention strategy are discussed, particularly as they relate to PEPFAR's very specific regulations for the allocation of funds. As PEPFAR funding constitutes over 95% of Mozambique's HIV-specific funding, these regulations and earmarks have created deep path dependence and whittled away at national and local ownership of policy. The third chapter of this thesis then focuses on Mozambique's severe human resources for health constraints and current efforts in health systems strengthening. These strategies include task shifting and human resources scale-up, issues which, while being general to the health system, are also inordinately important for continued ART scale-up. The fourth and final chapter contains the case study in Maputo, Mozambique. This qualitative study attempts to examine the effects of the sexual behavior prevention paradigm on people living with HIV and receiving ART. As these patients are our best hope for halting the HIV epidemic, it will be important for us to view our decades-old prevention messages from their point of view and understand how these messages may also affect their adherence as well as their willingness to be tested initially and to enroll in treatment. The interviews were carried out with patients, guardians of pediatric patients and clinicians at two health facilities in Maputo. Analysis of these interviews supports the hypothesis that traditional prevention messages found in public health campaigns, the media and in health facilities themselves, may be creating and exacerbating stigma that discourages people living with HIV to be tested and treated
Youth Political Organizations and Music in Contemporary Russia: the National Identity Issue
No full textThis dissertation studies the relationship existing between youth political organizations, music and national identity in contemporary Russia. In particular, it focuses on some of the most representative youth political organizations present in the city of St. Petersburg and aims at describing their contribution to the conceptualization of post-Soviet Russian national identity(ies), as captured through an analysis of their music
Sensing Social Interactions Using Non-Visual and Non-Auditory Mobile Sources, Maximizung Privacy and Minimizing Obtrusiveness.
No full textSocial interaction is one of the basic components of human life which impacts thoughts, emotions, decisions, and the overall wellbeing of individuals. In this regard, monitoring social activity constitutes an important factor for a number of disciplines, particularly the ones related to social and health sciences. Sensor-based social interaction data collection has been seen as a groundbreaking tool which has the potential to overcome the drawbacks of traditional self-reporting methods and to revolutionize social behavior analysis. However, monitoring social interactions typically implies a trade-off between the quality of collected data and the levels of unobtrusiveness and of privacy respecting, aspects which can affect spontaneity in subjects’ behavior. Despite the substantial research in the area of automatic recording of social interactions, the existing solutions remain limited: they either capture audio/video data which may raise privacy concerns in monitored subjects and may restrict the application to very specific areas, or provide low accuracy in detecting social interactions that occur on small spatio-temporal scale.
The objective of this thesis is to provide and evaluate a solution for mobile monitoring of face-to-face social interactions, which maximizes privacy and minimizes obtrusiveness. In order to reliably detect social interactions that occur on small spatio-temporal scale, the proposed solution infers two types of information, namely spatial settings between subjects and their speech activity status. The challenge was to select appropriate sources that do not restrict application scenarios only to certain areas and do not capture privacy sensitive data, which are the drawbacks of video/audio systems. The second stage was to interpret the data acquired from non-visual and non-auditory sources and to model social interactions on small space- and time- scales. The work in this thesis assesses the reliability of the proposed approach in several scenarios, demonstrating the accuracy of approximately 90% in detecting the occur-rence of face-to-face social interactions.
The feasibility of using the proposed approach for social interaction data collection is further evaluated with respect to the study of social psychology, which serves as the guideline for extracting the relevant features of social interactions. The evaluation has demonstrated the possibility to extract various nonverbal behavioral cues related to spatial organization between individuals and their vocal behavior in social interactions. By modeling social context using the extracted features, it is possible to achieve the accuracy of 81% in the automatic classification between formal versus informal social interactions. In addition, the proposed approach was applied to gather daily patterns of social activity for investigating their correlation with the mood changes in individuals, which has been explored so far only using the traditional self-reporting methods. The findings are consistent with previous studies thus indicating the possibility to use the proposed method of collecting social interaction data for investigating psychological effects of social activities
Comportamento strutturale di sistemi costruttivi in legno realizzati con pareti portanti intelaiate = Structural behavior of timber framed buildings
No full textThe research hereinafter describes aims at mechanically characterize the behavior of timber framed buildings, with particular focus on their behaviour in seismic zones. An
extensive experimental campaign divided into three phases has been completed in order to achieve this objective.
In the first phase tests on the connection between sheating panels and timber studs were conducted. Subsequently the behavior of the connections used for anchoring the walls to the foundation were investigated. In the second stage the full scale timber framed walls were subjected to tests. The walls were realized using different materials and different type of connections to the ground. The results have allowed the study of the individual structural components which constitute an entire building, from the single connector to the entire wall. In order to understand the behavior of the components themselves in a real building, and thus their interaction with each other in case of an earthquake, in the third step a shaking table test of a three-story building has been done. All tests have permitted to collect a wealth of data with which to populate a database to be used both to understand in detail the structural behavior of the timber framed building system and in also to validate the proposed formulations.
From the analytical point of view, an equation able to provide the horizontal displacement of a wall subject to a horizontal force has been developed. This equation was then
successfully validated by comparing the results with those obtained from laboratory tests.
For the execution of the tests have been created procedures and set-up ad hoc, that could be used also in the future to carry out similar tests. An important work has been
done to achieve a configuration suitable to test full scale timber framed walls through well controlling the boundary conditions
CROSS-LAYER ADAPTATION OF SERVICE-BASED SYSTEMS
No full textOne of the key features of service-based systems (SBS) is the capability to adapt in order to react to various changes in the business requirements and the application context. Given the complex layered structure, and the heterogeneous and dynamic execution context of such systems, adaptation is not at all a trivial task.
The importance of the problem of adaptation has been widely recognized in the community of software services and systems. There exist several adaptation approaches which aim at identifying and solving problems that occur in
one of the SBS layers. A fundamental problem with most of these works is their fragmentation and isolation. While these solutions are quite effective when the specific problem they try to solve is considered, they may be incompatible or even harmful when the whole system is taken into account. Enacting an adaptation in the system might result in triggering new problems.
When building adaptive SBSs precautions must be taken to consider the impacts of the adaptations on the entire system. This can be achieved by properly coordinating adaptation actions provided by the different analysis and decision mechanisms through holistic and multi-layer adaptation strategies. In this dissertation, we address this problem. We present a novel framework for Crosslayer
Adaptation Management (CLAM) that enables a comprehensive impact analysis by coordinating the adaptation and analysis tools available in the SBS.
We define a new system modeling methodology for adaptation coordination. The SBS model and the accompanying adaptation model that we propose in this thesis overcome the limitations of the existing cross-layer adaptation approaches: (i) genericness for accommodating diverse SBS domains with different system elements and layers (ii) flexibility for allowing new system artifacts and adaptation tools (iii) capability for dealing with the complexity of the SBS considering the possibility of a huge number of problems and adaptations that might take place in the system.
Based on this model we present a tree-based coordination algorithm. On the one hand it exploits the local adaptation and analysis facilities provided by the system, and on the other hand it harmonizes the different layers and system elements by properly coordinating the local solutions. The outcome of the algorithm is a set of alternative cross-layer adaptation strategies which are consistent with the overall system.
Moreover, we propose novel selection criteria to rank the alternative strategies and select the best one. Differently from the traditional approaches, we consider as selection criteria not only the overall quality of the SBS, but also
the total efforts required to enact an adaptation strategy. Based on these criteria we present two possible ranking methods, one relying on simple additive weighting - multiple criteria decision making, the other relying on fuzzy logic.
The framework is implemented and integrated in a toolkit that allows for constructing and selecting the cross-layer adaptation strategies, and is evaluated on a set of case studies