The thesis deals with automatic control the font size by the distance from the reader. It includes theoretical acquaintance with the face detection and subsequent tracking of the detected area during the scene. Furthermore, there is a comparison of the tracking algorithms. Then the calculation of distance is decribed. It is based on the user’s calibration and based on the outcome occurs the font size is automatically corrected. There is also a description of a separate application Automatical controller of the text size, with the recommended settings of the program.

INTRODUCTION - Plasminogen activator inhibitor type-1 (PAI-1) has a known relationship with obesity and more specifically with central obesity. Traditionally the physiological contribution of PAI-1 is seen as an indicator of fibrinolysis with increased PAI-1 levels contributing to decreased fibrinolysis. In more recent years, assays have been developed that not only uses proxy markers, such as PA-1, which is considered to be representative of fibrinolysis , but global assays that report on the global fibrinolytic potential of an individual, often reported as clot lysis time (CLT). Investigations into the relationship of CLT with obesity are scarce. Preliminary evidence shows that the relationship of CLT with obesity may differ from that of PAI-1 with obesity although in depth investigations in this regard are lacking. Therefore, the aim of this study was to investigate the association between fibrinolysis markers (PAI-1act and CLT) and various markers of body composition in the South African Prospective Urban and Rural Epidemiology (PURE) data collected during 2010. METHODS - Data collected in the PURE study in 2010 were cross-sectionally analysed. The participants (n = 1288) were apparently healthy black South-African men and women 35 years and older, residing in urban and rural settlements in the North-West Province. Experimental methods included anthropometric measurements such as height, weight, hip circumference, waist circumference, skinfolds (triceps, chest, abdominal, thigh and supra iliac skinfolds) and body composition measurements by means of air-displacement plethysmography and biolelectrical impedance analysis. Laboratory analysis of fibrinolysis markers, PAI-1act and CLT were also performed. MAIN FINDINGS - In men, similarities were seen regarding the relationship between PAI-1act and body composition markers and the relationships observed between CLT and body composition markers. In contrast, in the women more and stronger associations were observed between CLT and body composition markers compared to that observed between PAI-1act and body composition markers. CLT showed a linear relationship with body composition markers where PAI-1act levels plateaued at higher body composition categories. Possible reasons for the observed differences may be related to differences in adipose tissue distribution and sequence of accumulation between men and women. PAI-1 is associated with visceral adipose tissue (VAT) where high amounts of stromal cells are found. In men preferential accumulation of VAT may explain similarities in the relationship of PAI-1act with body composition and that of CLT with body composition. Proportionally less VAT, but more subcutaneous adipose tissue in women may explain the observed increase in CLT compared to PAI-1act levels that plateaued over body composition tertiles and categories. CONCLUSION - PAI-1act has a stronger association with central obesity while CLT has a stronger association with total body fat. In women PAI-1act and CLT showed different associations with body composition markers, whereas associations of PAI-1act and CLT with body composition were similar in men. PAI-1act is strongly influenced by type of body fat accumulation whereas CLT is associated with obesity independent of type and sequence of body fact accumulation. Significant associations observed between CLT and body composition variables are, therefore, at least in part, independent of PAI-1act. Additional factors such as, thrombin activatable fibrinolysis inhibitor (TAFI), α-2-antiplasmin, plasminogen, prothrombin and fibrin clot structure that influence CLT and are also related to obesity may additionally contribute to the link between CLT and obesity. / MSc (Dietetics), North-West University, Potchefstroom Campus, 2014

INTRODUCTION - Plasminogen activator inhibitor type-1 (PAI-1) has a known relationship with obesity and more specifically with central obesity. Traditionally the physiological contribution of PAI-1 is seen as an indicator of fibrinolysis with increased PAI-1 levels contributing to decreased fibrinolysis. In more recent years, assays have been developed that not only uses proxy markers, such as PA-1, which is considered to be representative of fibrinolysis , but global assays that report on the global fibrinolytic potential of an individual, often reported as clot lysis time (CLT). Investigations into the relationship of CLT with obesity are scarce. Preliminary evidence shows that the relationship of CLT with obesity may differ from that of PAI-1 with obesity although in depth investigations in this regard are lacking. Therefore, the aim of this study was to investigate the association between fibrinolysis markers (PAI-1act and CLT) and various markers of body composition in the South African Prospective Urban and Rural Epidemiology (PURE) data collected during 2010. METHODS - Data collected in the PURE study in 2010 were cross-sectionally analysed. The participants (n = 1288) were apparently healthy black South-African men and women 35 years and older, residing in urban and rural settlements in the North-West Province. Experimental methods included anthropometric measurements such as height, weight, hip circumference, waist circumference, skinfolds (triceps, chest, abdominal, thigh and supra iliac skinfolds) and body composition measurements by means of air-displacement plethysmography and biolelectrical impedance analysis. Laboratory analysis of fibrinolysis markers, PAI-1act and CLT were also performed. MAIN FINDINGS - In men, similarities were seen regarding the relationship between PAI-1act and body composition markers and the relationships observed between CLT and body composition markers. In contrast, in the women more and stronger associations were observed between CLT and body composition markers compared to that observed between PAI-1act and body composition markers. CLT showed a linear relationship with body composition markers where PAI-1act levels plateaued at higher body composition categories. Possible reasons for the observed differences may be related to differences in adipose tissue distribution and sequence of accumulation between men and women. PAI-1 is associated with visceral adipose tissue (VAT) where high amounts of stromal cells are found. In men preferential accumulation of VAT may explain similarities in the relationship of PAI-1act with body composition and that of CLT with body composition. Proportionally less VAT, but more subcutaneous adipose tissue in women may explain the observed increase in CLT compared to PAI-1act levels that plateaued over body composition tertiles and categories. CONCLUSION - PAI-1act has a stronger association with central obesity while CLT has a stronger association with total body fat. In women PAI-1act and CLT showed different associations with body composition markers, whereas associations of PAI-1act and CLT with body composition were similar in men. PAI-1act is strongly influenced by type of body fat accumulation whereas CLT is associated with obesity independent of type and sequence of body fact accumulation. Significant associations observed between CLT and body composition variables are, therefore, at least in part, independent of PAI-1act. Additional factors such as, thrombin activatable fibrinolysis inhibitor (TAFI), α-2-antiplasmin, plasminogen, prothrombin and fibrin clot structure that influence CLT and are also related to obesity may additionally contribute to the link between CLT and obesity. / MSc (Dietetics), North-West University, Potchefstroom Campus, 2014

Made available in DSpace on 2014-12-17T14:55:26Z (GMT). No. of bitstreams: 1 CarlosAS_capa_ate_pag11.pdf: 8554804 bytes, checksum: 527c12a0f823f4e4aba9c7b95df0eff4 (MD5) Previous issue date: 2002-09-06 / abstract / O desenvolvimento de t?cnicas autom?ticas para a identifica??o da presen?a de namat?ides em imagens capturadas atrav?s de c?meras acopladas em microsc?pios para an?lise e obten??o de m?todos de controle destes microorganismos, acarretar? em um enorme impacto financeiro considerando os preju?zos causados por esta praga ? agricultura. O objetivo deste trabalho, consiste no desenvolvimento de um sistema inteligente com base nas t?cnicas de processamento digital de imagens e redes neurais artificiais para detectar a presen?a de nemat?ides em imagens digitais capturadas via microsc?pio com c?mera acoplada. Os elementos b?sicos do sistema inteligente consiste de um m?dulo de pr?-processamento da imagem seguido pela auto-segmenta??o e, por fim, de um m?dulo de identifica??o de namet?ides. T?cnicas como transformada KLT, auto-contraste, morfologia matem?tica, redes neurais artificiais, dentre outras, s?o objeto de estudo deste trabalho. O uso de imagens reais foi requisito fundamental para avalia??o e valida??o das t?cnicas trabalhadas. No decorrer deste trabalho s?o descritas as etapas de aquisi??o, pr?-processamento, segmenta??o e extra??o de caracter?sticas das imagens bem como apresenta-se as redes neurais artificiais utilizadas e o sistema desenvolvido encerrando-se com os experimentos e conclus?es observadas

In this thesis, an investigation was performed to find ways of differencing between firesand vehicles at waste stations in hope of removing vehicles as a source of error duringearly fire detection. The existing system makes use of a heat camera, which rotates in 48different angles (also known as zones) in a fixed position. If the heat is above a certainvalue within a zone the system sounds the fire alarm.The rotation of the camera results in an unwanted displacement between two successiveframes within the same zone. By use of image registration, this displacement wasremoved. After the registration of an image, segmentation was performed where coldobjects are eliminated as an error source. Lastly, an analysis was performed upon thewarm objects.At the end, it was proven that the image registration had been a successful improvementof the existing system. It was also shown that vehicles can, to some extent, beeliminated as an error source. / I denna uppsats görs en undersökning av sätt att urskilja mellan bränder och fordon vid avfallsbunkrar, i hopp om att ta bortfordon som felkälla under tidig branddetektion. Dagens system använder sig av en värmekamera som roterar i 48 vinklar(även kallade zoner) från en fix position och larmar då det blir för varmt i någon zon.Roteringen av kameran medför en icke önskvärd förskjutning mellan två efterföljande bilder inom samma zon. Processenbildregistrering används för att eliminera denna förskjutning. Efter registreringen utförs en segmentering där kalla objekt tasbort som felkälla. När detta är utfört görs en analys av de varma objekten med en mängd mätningar.I slutet bevisas att registreringen har fungerat mycket väl, likaså att det går till viss del att eliminera fordon som felkällaunder tidig brandetektion.

With the development of posibilities of image processing, stereoscopy, prices of web cameras and power of computers an opportunity to multiply an experience with working with 3D programs showed. From the picture from webcamera an estimation of a pose of user's head can be made. According to this pose a view on 3D scene can be changed. Then, when user moves his head, he will have a feeling as if monitor was a window through which one can see the scene behind. With the system which is the result of this project it will be possible to easily and cheaply add this kind of behaviour to any 3D application.

We begin by studying field-theory amplitude relations such as the Kleiss-Kuijf, Bern-Carrasco-Johansson, Kawai-Lewellen-Tye and the double copy construction, which are important ingredients in this thesis. Going beyond the field-theory limit we study how the gauge-sector of the heterotic string relates to type I amplitudes through the single valued projection of multiple zeta values. At low energy and for a U(1) gauge group (a single brane) the type I amplitudes are generated by the Born-Infeld action, whereas the corresponding heterotic amplitudes vanish in this limit. As a simple exercise we study Yang-Mills theory deformed by a $F^4$ operator, which is the first correction induced by the Born-Infeld action. This exercise is then generalized by considering the four- and six-point amplitudes in Tseytlin's proposal for a non-Abelian Born-Infeld action. Comparing these amplitudes with those found in type I and heterotic string theory we attempt to gain more insight about the non-Abelian Born-Infeld action.

The thesis deals with the issue of tracking feature points earned from videosequences of hand helded camera. The work is focused on the case of moving camera and static background, and events that are associated with this case and can occur. There is studied the movement of the camera, which is given its direction and speed. The aim of this work is the election and the subsequent implementation of three fundamentally different methods suitable for tracking feature points in case of moving camera and their comparison according to set criteria. On the basis of comparison will be under pre-defined conditions chosen algorithm that is best able to deal with tracing these points.

The purpose of this thesis work was to develop a Hardware-in-the-Loop imaging setup that enables experimenting with an event-based and frame-based camera under simulated space conditions. The generated data sets were used to compare visual navigation algorithms in terms of an event-based and frame-based feature detection and tracking algorithm. The comparative analyses of the feature detection and tracking algorithms were used to get insights into the feasibility of event-based vision near-space space objects. Event-based cameras differ from frame-based cameras by how they produce an asynchronous and independent stream of events caused by brightness changes at each pixel instead of capturing images at a fixed rate. The setup design is based on a theoretical framework incorporating optical calculations. These calculations indicating the asteroid model needed to be scaled down by a factor of 3192 to fit inside the camera depth-of-view. This resulted in a scaled Bennu asteroid with a size of 16.44 centimeters.The cameras under testing conducted three experiments to generate data sets. The utilization of a feature detection and tracking algorithm on both camera data sets revealed that the absolute number of tracked features, computation time, and robustness in various scenarios of the frame-based camera algorithm outperforms the event-based camera algorithm. However, when considering the percentages of tracked features relative to the total detected features, the event-based algorithm tracks a significantly higher percentage of features for at least one key frame than the frame-based algorithm.  The comparative analysis of the experiments performed in space-simulated conditions during this project showed that the feasibility of an event-based camera using solely events is low compared to the frame-based camera.

Autonomous navigation for ground vehicles has many challenges. Autonomous systems must be able to self-localise, avoid obstacles and determine navigable surfaces. This thesis studies several aspects of autonomous navigation with a particular emphasis on vision, motivated by it being a primary component for navigation in many high-level biological organisms.  The key problem of self-localisation or pose estimation can be solved through analysis of the changes in appearance of rigid objects observed from different view points. We therefore describe a system for structure and motion estimation for real-time navigation and obstacle avoidance. With the explicit assumption of a calibrated camera, we have studied several schemes for increasing accuracy and speed of the estimation.The basis of most structure and motion pose estimation algorithms is a good point tracker. However point tracking is computationally expensive and can occupy a large portion of the CPU resources. In thisthesis we show how a point tracker can be implemented efficiently on the graphics processor, which results in faster tracking of points and the CPU being available to carry out additional processing tasks.In addition we propose a novel view interpolation approach, that can be used effectively for pose estimation given previously seen views. In this way, a vehicle will be able to estimate its location by interpolating previously seen data.Navigation and obstacle avoidance may be carried out efficiently using structure and motion, but only whitin a limited range from the camera. In order to increase this effective range, additional information needs to be incorporated, more specifically the location of objects in the image. For this, we propose a real-time object recognition method, which uses P-channel matching, which may be used for improving navigation accuracy at distances where structure estimation is unreliable. / Diplecs