Thesis (Ph.D.)--Boston University / After a review of scalar coherence theory the infinite-time averages of coherence theory are interpreted in terms of the conserved quantities of any scalar wave field and these averages are related to the finite-time averages of physical measurements. In particular it is shown that the infinite-time average of the square of the wave field (intensity) is proportional to the average energy flux under many, but not all, circumstances. By application of the energy conservation law for the scalar wave field it is shown that the average energy flux through a plane surface depends not only upon the intensity but also upon the correlation of the field. An explicit example of this dependence is given. Further the assumptions which underlie the association of infinite-time averages with actual physical measurements are given explicitly. After a review of ensemble coherence theory, an ergodic theorem which relates the time and ensemble average coherence theories is presented. In particular it is shown that if the boundary conditions are ergodic (i.e., the ensemble averages on the boundary are equal to the time averages), then the solutions are also ergodic. In Chapter VI the investigation is turned from the formal properties of coherence theory to an application of the theory to a particular problem in wave motion - the propagation of waves in a random medium. Random medium here means any region of space for which the speed of the waves varies randomly in both space and time. By invoking an ergodic hypothesis the time and space varying medium is replaced by an ensemble of media which vary only in space. For such media it is shown that the ensemble average behavior depends only upon the ensemble averaged, two-point cross correlation of the fluctuations in the index of refraction of the media. Further, an approximate solution to the problem of the propagation of a wave beam of finite cross -section and divergence (spread) through a slab of Gaussianly correlated random medium is given. The principle conclusions are that the slab produces mainly forward scattering and that the scattered wave is highly coherent. In Chapter VII a wave theory of imaging is developed from the equations of motion for the coherence. From this theory explicit representations for imaging in the cases of coherent and incoherent illumination are derived. These representations show that imaging with coherent illumination is basically nonlinear in terms of what is observable in the object plane and observable in the image plane. In Chapter VIII various consequences of the nonlinear equation governing imaging with coherent illumination are exhibited. Lacking a general theory of nonlinear equations, the properties of coherent imaging cannot be summarized by giving a Green's function or transfer function. Instead the nature of the images of simple geometrical objects are given in some detail. From examples of coherent imaging it is concluded that the two most striking features are that the images of edges "ring" and appear to be shifted in relation to the same images under incoherent illumination. By "ring" it is meant that the image of an edge is not a monotonic change in intensity, but rather, that interference fringes occur in the neighborhood of the location of the edge. Further, coherent imaging is linearized by restricting the object to be of low contrast. Having linearized coherent imaging, it is directly compared with incoherent imaging. Finally, a particular problem in optics is analyzed - that of the sparkle of laser light. It is shown that all the observed properties of the sparkle can be explained by considering the nature of the image of a coherently illuminated, rough surface. By a rough surface it is meant any surface which deviates randomly from a plane (or other simple geometrical surface that could be constructed to be coincident with a wavefront of the illumination). It is shown that the image of a coherently illuminated rough surface is as if incoherent illumination were used - edge ringing and shifting are not present - but that the image is modified by random fluctuations in intensity. These random fluctuations give the image a speckled appearance. It is shown that this speckling is Rayleigh distributed and the dependence of the statistical parameters upon the nature of the imaging system (lens) is exhibited.

<p>Savant syndrome is a rare condition in which some people have extraordinary talents despite some serious mental or physical disability. It is a syndrome with remarkable features, standing in stark contrast to a person’s overall character. The term savant, or idiot savant, describes a person who, in spite of low intelligence, has a skill in some specific narrow area. Savants can have a specific talent in, for instance, music, art, calendar calculation or foreign language but whatever the specific talent is, it is always connected to extraordinary memory. Savant syndrome seems to be also connected to autism or autistic characteristics. In this paper I aim to give a clear description of the savant syndrome and explain its connection to autism. Further, I present how specific theories try to describe the causes of savant syndrome, and connect the theories to results of empirical research in order to give an overall view of the syndrome’s appearance. I will also compare the theories and evaluate their strengths and weaknesses with respect to the discoveries and progress that has been made within the area of savant syndrome research.</p>

Submitted by Bruna Rodrigues (bruna92rodrigues@yahoo.com.br) on 2016-09-28T12:43:44Z No. of bitstreams: 1 DissTM.pdf: 842829 bytes, checksum: 853077899d252d353370dd8f9b86616d (MD5) / Approved for entry into archive by Marina Freitas (marinapf@ufscar.br) on 2016-10-10T19:04:27Z (GMT) No. of bitstreams: 1 DissTM.pdf: 842829 bytes, checksum: 853077899d252d353370dd8f9b86616d (MD5) / Approved for entry into archive by Marina Freitas (marinapf@ufscar.br) on 2016-10-10T19:04:35Z (GMT) No. of bitstreams: 1 DissTM.pdf: 842829 bytes, checksum: 853077899d252d353370dd8f9b86616d (MD5) / Made available in DSpace on 2016-10-10T19:04:42Z (GMT). No. of bitstreams: 1 DissTM.pdf: 842829 bytes, checksum: 853077899d252d353370dd8f9b86616d (MD5) Previous issue date: 2016-04-15 / Não recebi financiamento / Find fair (according to some criterion) prices for assets in financial markets is one of the most important pillars of Finance Theory. To accomplish this, the Asset Pricing Theory has a mathematical formulation, based mainly on Probability Theory. In this dissertation we present such theory, which is essentially based on mar- tingales, important objects of Probability Theory. Alternatively, we also present an Asset Pricing Theory based on the Coherence Theory of Bruno de Finetti in order to compare, informally, such approaches. / Encontrar preços justos (segundo algum critério) para ativos em mercados financeiros é um dos pilares mais importantes da Teoria de Finanças. Para alcançar esse objetivo, a Teoria de Precificação de Ativos tem uma formulação matemática, fundamentada principalmente na Teoria de Probabilidades. Neste trabalho apresentaremos tal teoria, que é essencialmente baseada em martingales, objetos de grande importância na Teoria de Probabilidades. Alternativamente, apresentaremos uma Teoria de Precificação baseada na Teoria da Coerência de Bruno de Finetti com o objetivo de comparar, de modo informal, tais teorias.

Die Arbeit untersucht theoretisch die Wechselwirkung neutraler Teilchen (Atome, Moleküle) mit Oberflächen, soweit sie durch das elektromagnetische Feld vermittelt wird. Spektrale Energiedichten und Kohärenzfunktionen werden hergeleitet und liefern eine umfassende Charakterisierung des Felds auf der sub-Wellenlängen-Skala. Die Ergebnisse finden auf zwei Teilgebieten Anwendung: in der integrierten Atomoptik, wo ultrakalte Atome an thermische Oberflächen koppeln, und in der Nahfeldoptik, wo eine Auflösung unterhalb der Beugungsbegrenzung mit einzelnen Molekülen als Sonden und Detektoren erzielt werden kann. / We theoretically discuss the interaction of neutral particles (atoms, molecules) with surfaces in the regime where it is mediated by the electromagnetic field. A thorough characterization of the field at sub-wavelength distances is worked out, including energy density spectra and coherence functions. The results are applied to typical situations in integrated atom optics, where ultracold atoms are coupled to a thermal surface, and to single molecule probes in near field optics, where sub-wavelength resolution can be achieved.

Savant syndrome is a rare condition in which some people have extraordinary talents despite some serious mental or physical disability. It is a syndrome with remarkable features, standing in stark contrast to a person’s overall character. The term savant, or idiot savant, describes a person who, in spite of low intelligence, has a skill in some specific narrow area. Savants can have a specific talent in, for instance, music, art, calendar calculation or foreign language but whatever the specific talent is, it is always connected to extraordinary memory. Savant syndrome seems to be also connected to autism or autistic characteristics. In this paper I aim to give a clear description of the savant syndrome and explain its connection to autism. Further, I present how specific theories try to describe the causes of savant syndrome, and connect the theories to results of empirical research in order to give an overall view of the syndrome’s appearance. I will also compare the theories and evaluate their strengths and weaknesses with respect to the discoveries and progress that has been made within the area of savant syndrome research.

A large amount of information is contained in textual records, which originate from a variety of sources such as handwritten records and digital media like audio and video files. The information contained in these records is unstructured and to visualise the content of the records is not a trivialtask.In order to visualise information contained in unstructured textual records, the information must be extracted from the records and transformed into a structured format. This research aimed to visualise the coherence of facts contained in textual sources in order to allow the user who make use of the visualisation to make an assumption about the validity of the textual records as a set. For the purpose of the study, it was contemplated that the coherence of facts contained in a document set was indicated by the multiple occurrences of the same fact over several documents in the set. The output of this research is a model that abstracts the process required to transform information contained in unstructured textual records into a structured format and the visual representation of the multiple occurrences of facts in order to support the process of making an assumption about the coherence of facts in the set. This assumption enables the user to make a decision.based on the coherence theory of truth.about the validity of the document set. The modelprovides guidance and practices for performing tasks on similar textualdocument sets containing secondary data. The development of the model was informed by a phased construction of three specific software solution instantiations.namely an initial information extraction, an intermediate visual representation and a final information visualisation instantiation. The final solution instantiation was demonstrated to research participants and was evaluated as well. A pragmatic design science research approach was followed in order to solve the research problem. In conducting the research an adaption of the Peffers et at. (2006) design research process model was followed. The result of the research is a model for the visual representation of the coherence of facts in a textual document set. Expert review of the model is added through a process of peer review and academic scrutiny by means of conference papers and a journal article. It is envisaged that the results of the research can be applied to a number of research fields such as Indigenous Knowledge, History and Law. / School of Computing / M. Sc. (Computing)

The dissertation thesis addresses the topic of mathematical tasks processing in students with autism spectrum disorder (ASD) and problematic points of their solution. The aim of this work is to delineate methods that ASD students use to approach these tasks and solve them. We focus primarily on whether it is possible to identify different procedures than those used by typically developing students, and whether these procedures show specifics corresponding to distinct cognitive processes. In the theoretical part we provide a theoretical background for the study. Firstly, we create a frame to understand the complexity of autism, furthermore we deal with psychological theories examining the topic, and describe specifics of development of ASD students during their adolescence. Thereafter, we reflect on studies addressing mathematical skills of ASD students. Mathematics is considered as their great strength, however is not sufficiently scrutinized, as highlighted by various international studies (for example Oswald et al., 2016). The empiric part is based on qualitative methodology and pursues comparisons of mathematical tasks processing between six ASD students and typically developing peers. We strive to document differences and common points in solutions as well as to analyze cognitive processes of...