A simple but efficient voice activity detection algorithm through Hilbert transform and dynamic threshold for speech pathologies

A simple but efficient voice activity detector based on the Hilbert transform and a dynamic threshold is presented to be used on the pre-processing of audio signals -- The algorithm to define the dynamic threshold is a modification of a convex combination found in literature -- This scheme allows the detection of prosodic and silence segments on a speech in presence of non-ideal conditions like a spectral overlapped noise -- The present work shows preliminary results over a database built with some political speech -- The tests were performed adding artificial noise to natural noises over the audio signals, and some algorithms are compared -- Results will be extrapolated to the field of adaptive filtering on monophonic signals and the analysis of speech pathologies on futures works

Dynamic set pieces for CAMBADA team

Robotics is an emergent branch of engineering that involves the conception, manufacture, and control of robots. It is a multidisciplinary field that combines electronics, design, computer science, artificial intelligence, mechanics and nanotechnology. Its evolution results in machines that are able to perform tasks with some level of complexity. Multi-agent systems is a researching topic within robotics, thus they allow the solving of higher complexity problems, through the execution of simple routines. Robotic soccer allows the study and development of robotics and multiagent systems, as the agents have to work together as a team, having in consideration most problems found in our quotidian, as for example adaptation to a highly dynamic environment as it is the one of a soccer game. CAMBADA is the robotic soccer team belonging to the group of research IRIS from IEETA, composed by teachers, researchers and students of the University of Aveiro, which annually has as main objective the participation in the RoboCup, in the Middle Size League. The purpose of this work is to improve the coordination in set pieces situations. This thesis introduces a new behavior and the adaptation of the already existing ones in the offensive situation, as well as the proposal of a new positioning method in defensive situations. The developed work was incorporated within the competition software of the robots. Which allows the presentation, in this dissertation, of the experimental results obtained, through simulation software as well as through the physical robots on the laboratory.

Dynamic instabilities in scalar neural field equations with space-dependent delays

In this paper we consider a class of scalar integral equations with a form of space-dependent delay. These non-local models arise naturally when modelling neural tissue with active axons and passive dendrites. Such systems are known to support a dynamic (oscillatory) Turing instability of the homogeneous steady state. In this paper we develop a weakly nonlinear analysis of the travelling and standing waves that form beyond the point of instability. The appropriate amplitude equations are found to be the coupled mean-field Ginzburg-Landau equations describing a Turing-Hopf bifurcation with modulation group velocity of O(1). Importantly we are able to obtain the coefficients of terms in the amplitude equations in terms of integral transforms of the spatio-temporal kernels defining the neural field equation of interest. Indeed our results cover not only models with axonal or dendritic delays but those which are described by a more general distribution of delayed spatio-temporal interactions. We illustrate the predictive power of this form of analysis with comparison against direct numerical simulations, paying particular attention to the competition between standing and travelling waves and the onset of Benjamin-Feir instabilities.

Why are some companies more successful than others? An exploration into organizational culture and dynamic capabilities

Why are some companies more successful than others? This thesis approaches the question by enlisting theoretical frameworks that explain the performance with internal factors, deriving from the resource-based view, namely the dynamic capabilities approach. To deepen the understanding of the drivers and barriers towards developing these higher order routines aiming at improving the operational level routines, this thesis explores the organisational culture and identity research for the microfoundational antecedents that might shed light on the formation of the dynamic capabilities. The dynamic capabilities framework in this thesis strives to take the theoretical concept closer to practical applicability. This is achieved through creation of a dynamic capabilities matrix, consisting of four dimensions often encountered in dynamic capabilities literature. The quadrants are formed along internal-external and resources-abilities axes, and consist of Sensing, Learning, Reconfiguration and Partnering facets. A key element of this thesis is the reality continuum, which illustrates the different levels of reality inherent in any entity of human individuals. The theoretical framework constructed in the thesis suggests a link between the collective but constructivist understanding of the organisation and both the operational and higher level routines, evident in the more positivist realm. The findings from three different case organisations suggest that the constructivist assumptions inherent to an organisation function as a generative base for both drivers and barriers towards developing dynamic capabilities. From each organisation one core assumption is scrutinized to identify its connections to the four dimensions of the dynamic capabilities. These connections take the form of drivers or barriers – or have the possibility to develop into one or the other. The main contribution of this thesis is to show that one key for an organisation to perform well in a turbulent setting, is to understand the different levels of realities inherent in any group of people. Recognising the intangible levels gives an advantage in the tangible ones.

Dynamic Programming Approaches for Estimating and Applying Large-scale Discrete Choice Models

People go through their life making all kinds of decisions, and some of these decisions affect their demand for transportation, for example, their choices of where to live and where to work, how and when to travel and which route to take. Transport related choices are typically time dependent and characterized by large number of alternatives that can be spatially correlated. This thesis deals with models that can be used to analyze and predict discrete choices in large-scale networks. The proposed models and methods are highly relevant for, but not limited to, transport applications. We model decisions as sequences of choices within the dynamic discrete choice framework, also known as parametric Markov decision processes. Such models are known to be difficult to estimate and to apply to make predictions because dynamic programming problems need to be solved in order to compute choice probabilities. In this thesis we show that it is possible to explore the network structure and the flexibility of dynamic programming so that the dynamic discrete choice modeling approach is not only useful to model time dependent choices, but also makes it easier to model large-scale static choices. The thesis consists of seven articles containing a number of models and methods for estimating, applying and testing large-scale discrete choice models. In the following we group the contributions under three themes: route choice modeling, large-scale multivariate extreme value (MEV) model estimation and nonlinear optimization algorithms. Five articles are related to route choice modeling. We propose different dynamic discrete choice models that allow paths to be correlated based on the MEV and mixed logit models. The resulting route choice models become expensive to estimate and we deal with this challenge by proposing innovative methods that allow to reduce the estimation cost. For example, we propose a decomposition method that not only opens up for possibility of mixing, but also speeds up the estimation for simple logit models, which has implications also for traffic simulation. Moreover, we compare the utility maximization and regret minimization decision rules, and we propose a misspecification test for logit-based route choice models. The second theme is related to the estimation of static discrete choice models with large choice sets. We establish that a class of MEV models can be reformulated as dynamic discrete choice models on the networks of correlation structures. These dynamic models can then be estimated quickly using dynamic programming techniques and an efficient nonlinear optimization algorithm. Finally, the third theme focuses on structured quasi-Newton techniques for estimating discrete choice models by maximum likelihood. We examine and adapt switching methods that can be easily integrated into usual optimization algorithms (line search and trust region) to accelerate the estimation process. The proposed dynamic discrete choice models and estimation methods can be used in various discrete choice applications. In the area of big data analytics, models that can deal with large choice sets and sequential choices are important. Our research can therefore be of interest in various demand analysis applications (predictive analytics) or can be integrated with optimization models (prescriptive analytics). Furthermore, our studies indicate the potential of dynamic programming techniques in this context, even for static models, which opens up a variety of future research directions.

Dinoflagellate Genomic Organization and Phylogenetic Marker Discovery Utilizing Deep Sequencing Data

Dinoflagellates possess large genomes in which most genes are present in many copies. This has made studies of their genomic organization and phylogenetics challenging. Recent advances in sequencing technology have made deep sequencing of dinoflagellate transcriptomes feasible. This dissertation investigates the genomic organization of dinoflagellates to better understand the challenges of assembling dinoflagellate transcriptomic and genomic data from short read sequencing methods, and develops new techniques that utilize deep sequencing data to identify orthologous genes across a diverse set of taxa. To better understand the genomic organization of dinoflagellates, a genomic cosmid clone of the tandemly repeated gene Alchohol Dehydrogenase (AHD) was sequenced and analyzed. The organization of this clone was found to be counter to prevailing hypotheses of genomic organization in dinoflagellates. Further, a new non-canonical splicing motif was described that could greatly improve the automated modeling and annotation of genomic data. A custom phylogenetic marker discovery pipeline, incorporating methods that leverage the statistical power of large data sets was written. A case study on Stramenopiles was undertaken to test the utility in resolving relationships between known groups as well as the phylogenetic affinity of seven unknown taxa. The pipeline generated a set of 373 genes useful as phylogenetic markers that successfully resolved relationships among the major groups of Stramenopiles, and placed all unknown taxa on the tree with strong bootstrap support. This pipeline was then used to discover 668 genes useful as phylogenetic markers in dinoflagellates. Phylogenetic analysis of 58 dinoflagellates, using this set of markers, produced a phylogeny with good support of all branches. The Suessiales were found to be sister to the Peridinales. The Prorocentrales formed a monophyletic group with the Dinophysiales that was sister to the Gonyaulacales. The Gymnodinales was found to be paraphyletic, forming three monophyletic groups. While this pipeline was used to find phylogenetic markers, it will likely also be useful for finding orthologs of interest for other purposes, for the discovery of horizontally transferred genes, and for the separation of sequences in metagenomic data sets.

I. Synthetic Studies Toward the Total Synthesis of Polycyclic Natural Products – Communesin F, Perophoramidine and Ineleganolide. II. Nickel Catalyzed Intramolecular C–O Bond Formation

Expedient synthetic approaches to the highly functionalized polycyclic alkaloids communesin F and perophoramidine are described using a unified approach featuring a key decarboxylative allylic alkylation to access a crucial and highly congested 3,3-disubstituted oxindole. Described are two distinct, stereoselective alkylations that produce structures in divergent diastereomeric series possessing the critical vicinal all-carbon quaternary centers needed for each synthesis. Synthetic studies toward these challenging core structures have revealed a number of unanticipated modes of reactivity inherent to these complex alkaloid scaffolds. Finally, a previously unknown mild and efficient deprotection protocol for the o-nitrobenzyl group is disclosed – this serendipitous discovery permitted a concise endgame for the formal syntheses of both communesin F and perophoramidine.

In addition, the atroposelective synthesis of PINAP ligands has been accomplished via a palladium-catalyzed C–P coupling process through dynamic kinetic resolution. These catalytic conditions allow access to a wide variety of alkoxy- and benzyloxy-substituted PINAP ligands in high enantiomeric excess.

An efficient and exceptionally mild intramolecular nickel-catalyzed carbon–oxygen bond-forming reaction between vinyl halides and primary, secondary, and tertiary alcohols has been achieved. This operationally simple method allows direct access to cyclic vinyl ethers in high yields in a single step.

Finally, synthetic studies toward polycyclic ineleganolide are described. The entire fragmented carbon framework has been constructed from this work. Highly (Z)-selective olefination was achieved by the method by the Ando group.

Assessing Decision Making Skill in Complex and Dynamic Environments Using Representative and Simulated Tasks

Traditional decision making research has often focused on one's ability to choose from a set of prefixed options, ignoring the process by which decision makers generate courses of action (i.e., options) in-situ (Klein, 1993). In complex and dynamic domains, this option generation process is particularly critical to understanding how successful decisions are made (Zsambok & Klein, 1997). When generating response options for oneself to pursue (i.e., during the intervention-phase of decision making) previous research has supported quick and intuitive heuristics, such as the Take-The-First heuristic (TTF; Johnson & Raab, 2003). When generating predictive options for others in the environment (i.e., during the assessment-phase of decision making), previous research has supported the situational-model-building process described by Long Term Working Memory theory (LTWM; see Ward, Ericsson, & Williams, 2013). In the first three experiments, the claims of TTF and LTWM are tested during assessment- and intervention-phase tasks in soccer. To test what other environmental constraints may dictate the use of these cognitive mechanisms, the claims of these models are also tested in the presence and absence of time pressure. In addition to understanding the option generation process, it is important that researchers in complex and dynamic domains also develop tools that can be used by `real-world' professionals. For this reason, three more experiments were conducted to evaluate the effectiveness of a new online assessment of perceptual-cognitive skill in soccer. This test differentiated between skill groups and predicted performance on a previously established test and predicted option generation behavior. The test also outperformed domain-general cognitive tests, but not a domain-specific knowledge test when predicting skill group membership. Implications for theory and training, and future directions for the development of applied tools are discussed.

A Digital Collection Center's Experience: ETD Discovery, Promotion, and Workflows in Digital Commons

This presentation was given at the Digital Commons Southeastern User Group conference at Winthrop University, South Carolina on June 5, 2015. The presentation discusses how the digital collections center (DCC) at Florida International University uses Digital Commons as their tool for ingesting, editing, tracking, and publishing university theses and dissertations. The basic DCC workflow is covered as well as institutional repository promotion.

Patient experiences of a bariatric group programme for managing obesity:a qualitative interview study

Objectives: People with obesity experience a range of physical and psychological ill-health outcomes. This study examined patients’ experiences of a group-based programme for the management of morbid obesity delivered within the UK National Health Service. The focus of the study was on the emerging dynamic of the group and patients’ perceptions of its impact on health outcomes. Design: A qualitative interview study was conducted and involved patients recruited from a Tier 3 bariatric service in South West England. Verbatim transcripts were analysed using thematic analysis. Methods: Twenty patients (12 females) with a BMI ≥ 35 kg/m2 participated in a semi-structured one-to-one interview. Participants had been registered with the bariatric service for at least 6 months. None of the participants had had bariatric surgery. Results: Most participants felt that they had benefited from participating in the group programme and talked about the group as a resource for lifestyle change. Participants’ narratives centred on the emergence of a sense of self based upon their participation in the group: establishing psychological connections to other patients, or shared social identity, was regarded as a key mechanism through which the programme's educational material was accessed, and underpinned the experience of social support within the group. Through interaction with other patients, involving the sharing of personal experiences and challenges, participants came to experience their weight ‘problem’ through a collective lens that they felt empowered them to initiate and sustain individual lifestyle change. Discussion: Bariatric care groups have the potential to support lifestyle change and weight loss and may help address the psychological needs of patients. Nurturing a sense of shared social identity amongst patients with morbid obesity should be a core aim of the care pathway and may provide the foundation for successful translation of dietetic content in group programmes.

The Dynamic and Changing Development of EERA Networks

In this article the authors use two EERA networks as a case for a discussion on the development of research networks within the European Educational Research Association (EERA). They contend that EERA networks through their way of working create a European research space. As their case shows, the development of networks is diverse. The emergence of networks and the current group of thirty-one networks do not display a coherent and unified system. Thus they argue that EERA networks have to be studied as an open complex system in order to comprehend the multiplicity and creative and innovative space that these networks represent. They create a space for knowledge production in a European context, enabling educational researchers to see and experience their research in a more diverse setting.

The EU ban on uncovered sovereign credit default swaps: assessing impacts on liquidity, volatility and price discovery

This article addresses the effects of the prohibition against naked CDS buying implemented by the European Union in November 2012. Three aspects of market quality are analyzed: liquidity, volatility, and price informativeness. Overall, our results suggest that the ban produced negative effects on liquidity and price informativeness. First, we find that in territories within the scope of the EU regulation, the bid–ask spreads on sovereign CDS contracts rose after the ban, but fell for countries outside its bounds. Open interest declined for both groups of CDS reference entities in our sample, but significantly more in the constraint group. Price delay increased more prominently for countries affected by the ban, whereas price precision decreased for these countries while increasing for CDSs written on other sovereign reference entities. Most notably, our findings indicate that hese negative effects were more pronounced amid reference entities exhibiting lower credit risk. With respect to volatility, the evidence suggests that the ban was successful in stabilizing the CDS market in that volatility decreased, particularly for contracts written on riskier CDS entities.

Life Design Counseling Group Intervention With Portuguese Adolescents

This article examines the process and outcome of a life design counseling group intervention with students in Grades 9 and 12. First, we applied a quasi-experimental methodology to analyze the intervention’s effectiveness in promoting career certainty, career decision-making, self-efficacy, and career adaptability in a sample of 236 students. Second, focus groups comprising 33 participants were conducted, examining participants’ perceptions of the intervention process and outcome. Our findings showed that the intervention had a significant effect on both career certainty and career self-efficacy, but it had no effect on career adaptability. Our results also showed that My Career Story (MCS) had a stronger effect on Grade 12 students. Focus group participants reported on the usefulness of MCS, as well as on its benefits, which include increased information as well as a sense of direction, self-discovery, connection, and increased self-awareness. Grade 9 participants expressed more difficulties in narrating self-experience than Grade 12 participants did. Implications for future research and practice are discussed.

E-cadherin and Choline Kinase: two challenging drug discovery targets

The data presented in this thesis was generated using molecular biology, protein chemistry and X-ray crystallography techniques. However, while the methodologies employed are essentially the same, the research work presented here refers to two different proteins, which are part of different research projects in the laboratory. For this reason, the content of this thesis is divided in two independent parts, each provided with an introduction and a general overview of the research topic and state-ofthe- art, a materials and methods section discussing the techniques used and the protocols followed, and a section where the results are presented and discussed in detail. The first half of the thesis deals with the structural characterization of the complex between human E-cadherin and three different small molecule potential inhibitors identified via a fragment-based drug discovery (FBDD) screening campaign that was conducted using a library of commercially available small fluorinated chemical fragments. For this screening phase, we used 19F-NMR as readout. The NMR experiments were done by our collaborator Dr. Marina Veronesi at the D3 PharmaChemistry division of the Italian Institute of Technology (IIT) in Genova (Italy). Functional cell adhesion assays to validate the inhibitory effects of the fragments thus identified were carried out in collaboration with Prof. Frédéric André at the University of Marseille (France). The second half of the thesis describes the structural characterization of Plasmodium falciparum Choline Kinase (PfChoK), an important pharmaceutical target in the fight against malaria, as well as the biochemical characterization of a library of potential inhibitors of PfChoK. These inhibitors were synthetized in the group of Prof. Luisa Carlota López-Cara at the Department of Pharmaceutical and Organic Chemistry of the University of Granada (Spain) in the framework of an ongoing collaboration between the two groups.