La mayoría de problemas en Visión por computador no contienen una relación directa entre el estímulo que proviene de sensores de tipo genérico y su correspondiente categoría perceptual. Este tipo de conexión requiere de una tarea de aprendizaje compleja. De hecho, las formas básicas de energía, y sus posibles combinaciones, son un número reducido en comparación a las infinitas categorías perceptuales correspondientes a objetos, acciones, relaciones entre objetos, etc. Dos factores principales determinan el nivel de dificultad de cada problema específico: i) los diferentes niveles de información que se utilizan, y ii) la complejidad del modelo que se emplea con el objetivo de explicar las observaciones. La elección de una representación adecuada para los datos toma una relevancia significativa cuando se tratan invariancias, dado que estas siempre implican una reducción del los grados de libertad del sistema, i.e., el número necesario de coordenadas para la representación es menor que el empleado en la captura de datos. De este modo, la descomposición en unidades básicas y el cambio de representación dan lugar a que un problema complejo se pueda transformar en uno de manejable. Esta simplificación del problema de la estimación debe depender del mecanismo propio de combinación de estas primitivas con el fin de obtener una descripción óptima del modelo complejo global. Esta tesis muestra como los Modelos de Variables Latentes reducen dimensionalidad, que teniendo en cuenta las simetrías internas del problema, ofrecen una manera de tratar con datos parciales y dan lugar a la posibilidad de predicciones de nuevas observaciones.Las líneas de investigación de esta tesis están dirigidas al manejo de datos provinentes de múltiples fuentes. Concretamente, esta tesis presenta un conjunto de nuevos algoritmos aplicados a dos áreas diferentes dentro de la Visión por Computador: i) video análisis y sumarización y ii) datos range 3D. Ambas áreas se han enfocado a través del marco de los Modelos Generativos, donde se han empleado protocolos similares para representar datos. / The majority of problems in Computer Vision do not contain a direct relation between the stimuli provided by a general purpose sensor and its corresponding perceptual category. A complex learning task must be involved in order to provide such a connection. In fact, the basic forms of energy, and their possible combinations are a reduced number compared to the infinite possible perceptual categories corresponding to objects, actions, relations among objects... Two main factors determine the level of difficulty of a specific problem: i) The different levels of information that are employed and ii) The complexity of the model that is intended to explain the observations.The choice of an appropriate representation for the data takes a significant relevance when it comes to deal with invariances, since these usually imply that the number of intrinsic degrees offreedom in the data distribution is lower than the coordinates used to represent it. Therefore, the decomposition into basic units (model parameters) and the change of representation, make that a complex problem can be transformed into a manageable one. This simplification of the estimation problem has to rely on a proper mechanism of combination of those primitives in order to give an optimal description of the global complex model. This thesis shows how Latent Variable Models reduce dimensionality, taking into account the internal symmetries of a problem, provide a manner of dealing with missing data and make possible predicting new observations. The lines of research of this thesis are directed to the management of multiple data sources. More specifically, this thesis presents a set of new algorithms applied to two different areas in Computer Vision: i) video analysis and summarization, and ii) 3D range data. Both areas have been approached through the Generative Models framework, where similar protocols for representing data have been employed.

A superconducting Transition Edge Sensor (TES) can be used to make the most sensitive thermometer which operates in a very narrow temperature range. The thin film bi-layer fabrication details are discussed as well as application in condensed matter physics. These include: measurement of quasi-adiabatic latent heat of superconducting transition, cobalt thermometry and photon detection.

A superconducting Transition Edge Sensor (TES) can be used to make the most sensitive thermometer which operates in a very narrow temperature range. The thin film bi-layer fabrication details are discussed as well as application in condensed matter physics. These include: measurement of quasi-adiabatic latent heat of superconducting transition, cobalt thermometry and photon detection.

Bakgrund: Perioden innan den aktiva förlossningsfasens start benämns latensfas. Den är svårdefinierad eftersom den kan yttra sig på olika sätt och varierar i längd. Blivande föräldrar som anländer till förlossningsavdelning söker stöd och bekräftelse hos barnmorskan när de tror att förlossningen har startat men är oroliga för att bli hemskickade igen. Syftet: Att undersöka och belysa förstagångsföräldrars upplevelser av latensfas. Metod: Semistrukturerad intervjustudie, data bearbetades med hjälp av kvalitativ innehållsanalys. Deltagare: Fem svensktalande förstagångsföräldrapar och en förstföderska som fått barn juni-augusti, år 2011. Resultat: Förlossningstarten upplevdes av blivande föräldrarna som en känslomässigt laddad period präglad av blandade känslor. Svårhanterbar smärta och behov av bekräftelse initierade deras sökande av stöd hosbarnmorskan. Lugnande besked och valmöjligheter upplevdes av paren som positivt oavsett om de fick återvända hem. Blivande fäderna upplevde att de hade svårt att känna sig delaktiga och stödja sin partner under latensfasen. Slutsats: Barnmorskans stödjande roll ansågs viktig för de blivande föräldrarna under latensfasen. Därför uttrycker de behov av individuellt anpassat stöd i föräldraskap. För blivande föräldrar är det viktigt att barnmorskan/vårdpersonalen tar dem på allvar, stödjer dem samt ser den blivande pappan som en likvärdig person vid deras barns födelse. / Background: The time period before the true labor phase begins is called latent phase. It is hard to define because it can manifest it self in different ways and vary in length. When soon parents-to-be arrives at the maternity ward and think their labour started, they look for support and acknowledgement from the midwife, but they worries to be sent back home again. Purpose: To research and expound the experiences from pre-labor of first-time parents. Method: Conduct semistructured interviews, process collected data using qualitative content analysis. Participants: Five Swedish speaking first-time parents and one first-time mother that have given birth June-August 2011. Results: These soon to be parents experienced the start of the delivery process as extra emotional period of time filled with mixed feelings. The one come of intense pain and the need of confirmation initiated their search for support from the midwife. Answers to their questions and possible choices were perceived as calming and positive even if they had to return home. The soon to be fathers had difficulty in feeling that they had an active role during the latent phase period and thus found it difficult to express support for their spouses. Conclusion: The midwife’s supporting role is considered important by the parents-to-be during the latent phase. They express a need for custom planned training for prenatal parenting. Soon to be parents its`important that the midwife/medical-staff should be taken them seriously, support the mand that the father-to-be is regarded as an equal participant in their child’s birth.

<p>Eating disorders pose a serious threat to the physical and mental health of those who suffer from them. Given the impact of these disorders and difficulty treating them, it is important to understand the nature of them and factors involved in their development and maintenance. The empirical investigation of eating disorders is made difficult by the extreme heterogeneity seen within current DSM-IV diagnostic categories. Research on emotion regulation in eating disorders is rising, yet scant in terms of identifying specific difficulties and points of intervention. The proposed study focused on the construct of emotion regulation and its relation to the eating disorders by: (1) empirically identifying groups of eating disorder participants based on symptoms and (2) examining specific difficulties in emotion regulation capacities in each of the identified groups of eating disorder participants and (3) identifying whether difficulties in emotion regulation contribute to eating disorder symptom severity. A clinical sample of individuals with eating disorders was classified into subgroups based on symptom frequency using latent profile analysis. The most parsimonious and best fitting model was a four-profile solution which resulted in four distinct subgroups. Profile 1 consisted of individuals who endorsed moderate restriction and occasional binge eating and vomiting, all at a subclinical level. Profiles 2, 3, and 4 all met criteria for bulimia nervosa and consisted of individuals who engaged in restriction, binge eating, and purging though in varying degrees. When these groups were compared to a sample of college aged healthy control participants using multivariate analysis of variance, results indicate that individuals in profile 1, which comprised 71% of the sample, experience greater difficulty with emotion regulation in the areas of awareness, nonacceptance, and perceived access to strategies to help them feel better. Results of three hierarchical regression analyses showed that difficulties in emotion regulation did not significantly contribute to symptom severity as anticipated..</p> / Dissertation

Owing to the development of Internet, excessive online data drive users to apply tools to assist them in obtaining desired and useful information. Information retrieval techniques serve as one of the major assistance tools that ease users¡¦ information processing loads. However, most current IR models do not consider processing streaming information which essentially characterizes today¡¦s Web environment. The approach to re-building models based on the full knowledge of data at hand triggered by the new incoming information every time is impractical, inefficient, and costly. Instead, IR models that can be adapted to streaming information incrementally should be considered under the dynamic environment. Therefore, this research is to propose an IR related technique, the incremental aspect model (ISM), which not only uncovers latent aspects from the collected documents but also adapts the aspect model on streaming documents chronologically. There are two stages in ISM: in Stage I, we employ probabilistic latent semantic indexing (PLSI) technique to build a primary aspect model; and in Stage II, with out-of-date data removing and new data folding-in, the aspect model can be expanded using the derived spectral method if new aspects significantly exist. Three experiments are conducted accordingly to verify ISM. Results from the first two experiments show the robust performance of ISM in incremental text clustering tasks. In Experiment III, ISM performs the task of storylines tracking on the 2010 Soccer World Cup event. It illustrates ISM¡¦s incremental learning ability to discover different themes around the event at any time. The feasibility of our proposed approach in real applications is thus justified.

To manage the information flood in the Internet, we usually navigate specific information using the provided search engines. Search engines are convenient but with limited functions. For example, it is impractical and impossible to browse through the entire collected information for us to gain an overall picture about what the navigated information stands for. To do so, we need an appropriate approach to automatically extracting concepts from the navigated information to assist users to easily and quickly gain the primary understanding toward a topic that interests users. In this research, we propose an approach to extracting concepts from the navigated web information and detecting the concept changes over time. It basically includes two stages. In the first stage, information is decomposed into paragraphs and they are clustered with key terms identified through the aid of latent semantic indexing method. Concepts are represented in the form of paragraph summary and associated key terms, which allows the user to easily comprehend what they describe. The second stage is to adaptively modify the concept structure to detect concept changes. With new information added, the concepts could be merging, splitting, or even emerging with time. Three experiments are conducted in this research to verify the proposed approach. Results of the first and second experiments show both high recall and high precision that matches the predefined concept categories. The last one is an illustrated real case application on the tsunami event. It shows that we can easily grasp different concepts of the tsunami reports and realize their changes by using our approach. The feasibility of employing our approach is thus justified.

Shape Memory Alloys (SMA) are a group of metallic alloys that have the ability to return to some previously defined shape or size when subjected to an appropriate thermal cycling procedure. In recent years there has been a lot of research on the development of small, light and, yet, powerful actuators for use in areas like robotics, prosthetics, biomimetics, shape control and grippers. Many of the miniaturized conventional actuators do not have sufficient power output to be useful and SMAs can be used advantageously here. The widespread use of SMAs in actuators is limited by their low bandwidth. Use of SMAs in two-way actuators requires that they undergo thermal cycling (heating and cooling). While SMAs can be heated quickly by resistive heating, conventional convection cooling mechanisms are much slower as the exothermic austenitic to martensitic phase transformation is accompanied by the release of significant amount of latent heat. While a number of cooling mechanisms have been studied in SMA actuator literature, most of the cooling mechanisms involve unidirectional forced convection. This may not be the most effective method. Oscillating flow in a channel can sometimes enhance heat transfer over a unidirectional flow. One possible explanation for this heat transfer enhancement is that the oscillatory flow creates a very thin Stokes viscous boundary-layer and hence a large time-dependent transverse temperature gradient at the heated wall. Therefore heat transfer takes place at a large temperature difference, thereby enhancing the heat transfer. In this work, the heat transfer from an SMA actuator under an oscillating channel is investigated and is compared to steady, unidirectional flow heat transfer. Oscillating flow is simulated using a finite volume based method. The resulting velocity field is made use of in solving the heat transfer problem using a finite difference scheme. A parametric study is undertaken to identify the optimal flow conditions required to produce the maximum output for a given geometry of the SMA actuator. The latent heat of transformation of the SMA is accounted for by means of a temperature dependent specific heat.

<p>This thesis deals with the reliability and life-time ofelectronic components and ways to determine these factors.Plastic encapsulated and open test circuits were assessed atdifferent humidity and temperature conditions. From the resultsan acceleration factor could be derived using the Arrheniusrelation. This factor is used to determine failure rates atdifferent drift conditions under accelerated test conditions. Aformula for the factor containing both relative humidity andtemperature could be established and was found to hold also formeasurements published by others.</p><p>Electrostatic discharge (ESD) transients were studiedexperimentally and by simulation with good agreement. A verysensitive method to detect latent failures of two kinds wasintroduced by nonlinearity measurements utilizing the thirdharmonic of a test signal. The ESD-susceptibility dependence ondesign and technology is shown and can be used to improvebuilt-in reliability.</p><p>Influences in the performance of semiconductor devices fromdefects like fixed charges and ions were interpreted for thefirst time by simulation using a 2D- finite element componentprogram. Significant results gave an application to a MOSFETdevice showing parameter derating, especially the change of thethreshold value. A short description of later development insimulation methods with new, more powerful tools improvingcomponent performance and reliability is given.</p><p>Charged thin films of Teflon, so called<i>electrets</i>, are used as microphone membranes. Theelectret voltage is a suitable reliability factor. Fromexperimental results a mathematical relation including thetemperature was established for the rate of decay of theelectret voltage with time. A method to charge the electretswith radioactive sources is outlined and described in apatent.</p><p>Finally an attempt was done to analyze the reliability ofthin film circuits by mathematical methods. Bell Labsintroduced<i>RC</i>-feedback filters realized in tantalum thin filmtechnology. The phase shift of the filter is about π or180°. A mathematical apparatus was developed to calculatethe change in frequency and attenuation from small componentvariations in resistors and capacitors. First and higher ordercorrections were derived, using expansion by the Taylor seriesfor the higher order.</p><p><b>Keywords:</b>reliability, failure mechanism, accelerationtests, ESD, latent failure, plastic encapsulation, electret,thin film</p>

The abilities of life insurers can be divided and measured from various aspects. Through the use of structural equation modeling, we investigate the relations among solvency, operation ability and profitability in year 1994, 1995 and 1996. After within-year analysis and longitudinal data analysis, we found that operation ability has a positive influence on the size and income of life insurers and has a slight negative effect on the return on capital during these years. While the effect of solvency, asset risk and product risk on return on capital is not significant. / text