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[pt] Os últimos anos testemunharam o uso crescente de dispositivos que rastreiam objetos móveis: equipamentos com GPS e telefones móveis, veículos ou outros sensores da Internet das Coisas, além de dados de localização de check-ins de redes sociais. Estes dados de mobilidade são representados como trajetórias, e armazenam a sequência de posições de um objeto móvel. Porém, estas sequências representam somente os dados de posição originais, que precisam ser semanticamente enriquecidos para permitir tarefas de análise e apoiar um entendimento profundo sobre o comportamento do movimento. Um outro espaço de dados global sem precedentes tem crescido rapidamente, a Web de Dados, graças à iniciativa de Dados Interligados. Estes dados semânticos ricos e livremente disponíveis fornecem uma nova maneira de enriquecer dados de trajetória. Esta tese apresenta contribuições para os desafios que surgem considerando este cenário. Em primeiro lugar, a tese investiga como dados de trajetória podem se beneficiar da iniciativa de dados interligados, guiando todo o processo de enriquecimento semântico utilizando fontes de dados externas. Em segundo lugar, aborda o tópico de computação de similaridade entre entidades representadas como dados interligados com o objetivo de computar a similaridade entre trajetórias semanticamente enriquecidas. A novidade da abordagem apresentada nesta tese consiste em considerar as características relevantes das entidades como listas ranqueadas. Por último, a tese aborda a computação da similaridade entre trajetórias enriquecidas comparando a similaridade entre todas as entidades representadas como dados interligados que representam as trajetórias enriquecidas. / [en] The last years witnessed a growing number of devices that track moving objects: personal GPS equipped devices and GSM mobile phones, vehicles or other sensors from the Internet of Things but also the location data deriving from the Social Networks check-ins. These mobility data are represented as trajectories, recording the sequence of locations of the moving object. However, these sequences only represent the raw location data and they need to be semantically enriched to be meaningful in the analysis tasks and to support a deep understanding of the movement behavior. Another unprecedented global space that is also growing at a fast pace is the Web of Data, thanks to the emergence of the Linked Data initiative. These freely available semantic rich datasets provide a novel way to enhance trajectory data. This thesis presents a contribution to the many challenges that arise from this scenario. First, it investigates how trajectory data may benefit from the Linked Data Initiative by guiding the whole trajectory enrichment process with the use of external datasets. Then, it addresses the pivotal topic of the similarity computation between Linked Data entities with the final objective of computing the similarity between semantically enriched trajectories. The novelty of our approach is that the thesis considers the relevant entity features as a ranked list. Finally, the thesis targets the computation of the similarity between enriched trajectories by comparing the similarity of the Linked Data entities that represent the enriched trajectories.

Digitale 3D-Modelle der Architektur haben innerhalb der letzten fünf Jahrzehnte sowohl die analogen, auf Papier basierenden Zeichnungen als auch die physischen Modelle aus ihrer planungs-, ausführungs- und dokumentationsunterstützenden Rolle verdrängt. Als Herausforderungen bei der Integration von 3D-Modellen in digitale Bibliotheken und Archive sind zunächst die meist nur rudimentäre Annotation mit Metadaten seitens der Autoren und die nur implizit in den Modellen vorhandenen Informationen zu nennen. Aus diesen Defiziten resultiert ein aktuell starkes Interesse an inhaltsbasierter Erschließung durch vernetzte Nutzergruppen oder durch automatisierte Verfahren, die z.B. aufgrund von Form- oder Strukturmerkmalen eine automatische Kategorisierung von 3D-Modellen anhand gegebener Schemata ermöglichen. Die teilweise automatische Erkennung von objektinhärenter Semantik vergrößert die Menge an diskreten und semantisch unterscheidbaren Einheiten. 3D-Modelle als Content im World Wide Web können sowohl untereinander als auch mit anderen textuellen wie nichttextuellen Objekten verknüpft werden, also Teil von aggregierten Dokumenten sein. Die Aggregationen bzw. der Modellkontext sowie die inhärenten Entitäten erfordern Instrumente der Organisation, um dem Benutzer bei der Suche nach Informationen einen Mehrwert zu bieten, insbesondere dann, wenn textbasiert nach Informationen zum Modell und zu dessen Kontext gesucht wird. In der vorliegenden Arbeit wird ein Metadatenmodell zur gezielten Strukturierung von Information entwickelt, welche aus 3D-Architekturmodellen gewonnen wird. Mittels dieser Strukturierung kann das Modell mit weiterer Information vernetzt werden. Die Anwendung etablierter Ontologien sowie der Einsatz von URIs machen die Informationen nicht nur explizit, sondern beinhalten auch eine semantische Information über die Relation selbst, sodass eine Interoperabilität zu anderen verfügbaren Daten im Sinne der Grundprinzipien des Linked-Data-Ansatzes gewährleistet wird. / Digital 3D models from the domain of architecture have replaced analogue paper-based drawings as well as haptic scale models bit by bit during the last five decades. The main challenges for integrating 3D models in digital libraries and archives are posed by mostly only sparse annotation with metadata provided by the author and the fact that information is only implicitly available. This has recently led to an increased interest in context-based indexing using automatic approaches as well as social tagging. Computer based approaches usually rely on methods from artificial intelligence including machine learning for automated categorization based on geometric and structural properties according to a given classification scheme. The partially automated recognition of model-inherent semantics increases the number of discrete and semantically distinguishable entities. 3D models as parts of the World Wide Web can be interlinked which each other. Aggregations as well as the model context along with inherent entities require efficient tools for organization in order to provide real additional benefits for the user during its quest for information. Especially for text-based search on information about a 3D model and its context, a metadata model is an indispensable tool regarding the above described challenges. In this work we develop a metadata model for specific structuring of information, which is obtained from 3D architectural models. Using this structure, the model can be linked to further information. The application of established ontologies and the use of URIs make the information not only explicitly, but also provide semantic information about the relation itself. By that, interoperability according to the principles of the LOD approach is guaranteed.

In den letzten Jahren haben sich spezielle Prinzipien zur Veröffentlichung strukturierter Daten im World Wide Web (WWW) etabliert. Diese Prinzipien erlauben es, von den jeweils angebotenen Daten auf weitere, nach den selben Prinzipien veröffentlichten Daten zu verweisen. Die daraus resultierende Form von Web-Daten wird entsprechend als Linked Data bezeichnet. Mit der Veröffentlichung von Linked Data im WWW entsteht ein sehr großer Datenraum, welcher Daten verschiedenster Anbieter miteinander verbindet und neuartige Möglichkeiten für Web-basierte Anwendungen bietet. Als Basis für die Entwicklung solcher Anwendungen haben mehrere Forschungsgruppen begonnen, Ansätze zu untersuchen, welche diesen Datenraum als eine Art verteilte Datenbank auffassen und die Ausführung deklarativer Anfragen über dieser Datenbank ermöglichen. Forschungsarbeit zu theoretischen Grundlagen der untersuchten Ansätze fehlt jedoch nahezu vollständig. Die vorliegende Dissertation schließt diese Lücke. / During recent years a set of best practices for publishing and connecting structured data on the World Wide Web (WWW) has emerged. These best practices are referred to as the Linked Data principles and the resulting form of Web data is called Linked Data. The increasing adoption of these principles has lead to the creation of a globally distributed space of Linked Data that covers various domains such as government, libraries, life sciences, and media. Approaches that conceive this data space as a huge distributed database and enable an execution of declarative queries over this database hold an enormous potential; they allow users to benefit from a virtually unbounded set of up-to-date data. As a consequence, several research groups have started to study such approaches. However, the main focus of existing work is to address practical challenges that arise in this context. Research on the foundations of such approaches is largely missing. This dissertation closes this gap.

Diese Arbeit besteht aus empirischen und methodischen Beiträgen zur Literatur über den deutschen Lohnunterschied zwischen Männern und Frauen. Bisher war es aus Mangel an geeigneten Daten nicht möglich, den potentiellen Einfluss von Arbeitgebern bzw. Firmen auf diesen Lohnunterschied zu untersuchen. Auf der Basis neuer Linked Employer-Employee Daten wird dies in drei empirischen Studien untersucht. Die erste Studie wendet sich dem innerbetrieblichen Lohnunterschied zu. Dabei zeigt sich, dass dieser stark über die Firmen schwankt. Demnach weisen Unternehmen mit einem Betriebsrat und solche, die Tarifverträge anwenden, geringere Lohnunterschiede auf. Firmen, die einem starken Wettbewerbsdruck ausgesetzt sind, nehmen weniger Entlohnungsunterschiede zwischen den Geschlechtern vor. In der zweiten Studie steht die Frage, wie viel des beobachteten Lohnunterschieds durch verschiedene individuelle Merkmale und wie viel durch die Selektion in unterschiedliche Betriebe erklärt werden kann, im Mittelpunkt. Dazu wird eine Zerlegung in vier Komponenten mit einem Verfahren von Machado und Mata (2005) über die ganze Lohnverteilung vorgenommen. Die Analyse zeigt, dass der Lohnunterschied am unteren Rand der Lohnverteilung am höchsten ist. Dies ist auf die Segregation von Frauen in weniger erfolgreiche und produktive Firmen zurückzuführen. Dagegen haben Unterschiede in der Humankapitalausstattung nur einen geringen Einfluss. In der dritten Studie wird die Beziehung zwischen dem Frauenanteil in Unternehmen und dem Lohn untersucht. Ein hoher Frauenanteil innerhalb von Unternehmen könnte eine für Frauen attraktive Arbeitsumgebung, geringe Qualifikationsanforderungen von Seiten der Arbeitgeber oder weniger Diskriminierung gegenüber Frauen widerspiegeln. Die Analyse zeigt, dass auch bei sukzessiver Berücksichtigung von individuellen und Firmenmerkmalen, der Frauenanteil einen negativen Einfluss auf den Lohn hat. Insbesondere eine attraktive Arbeitsumgebung führt zu einem geringen Lohn in frauendominierten Firmen. / This thesis consists of empirical and methodological contributions to the literature on the German gender wage gap. Due to a lack of appropriate data, previous studies have been unable to document the potential impact of employers and establishments on the gender wage gap. We investigate these issues using a newly available Linked Employer-Employee Dataset. The first study pays attention to the gender wage gap within establishments. We find that the gender wage gap varies tremendously across establishments. Establishments with work councils and those covered by collective wage agreements are found to have a smaller wage gap. Furthermore, establishments operating under strong product market competition behave in a more egalitarian way. In the second study, the key issue is to disentangle gender differences in human capital endowment and the segregation of men and women in different types of establishments as sources of wage inequality. Using an approach of Machado and Mata (2005), we apply a decomposition method extended to four terms across the entire wage distribution. The analysis shows that the gap is highest in the lower part of the wage distribution. This is largely explained by segregation of women into less successful and productive firms. Gender differences in the human capital endowment have a lesser impact upon the gap. The third study comprises an investigation of the relationship between the share of women in establishments and the wages of both sexes. For this correlation, hypotheses are formulated as to what a high proportion of women in an establishment can indicate: attractive working conditions for women, lower qualification requirements or less discrimination against women. The results show, that even when including worker and establishment covariates, a higher share of female employees reduces wages for both males and females. In particular, attractive working conditions lead to lower wages in female dominated establishments.

Doctor of Philosophy / Department of Grain Science and Industry / Yong Cheng Shi / This study focused on in-vitro digestibility and pasting properties of cross-linked (CL) starch with different amylose contents and different cross-linking levels, as well as physicochemical properties of extruded wheat flours with different amylose contents and functionality of amylopectin and cross-linking in improving the textural and physical properties of oat flour extrudates. Starch was CL by phosphorylation using a mixture of sodium trimetaphosphate and sodium tripolyphosphate at the ratio of 99:1 under alkaline condition. The digestibility of highly CL maize starches with different amylose contents was determined by Englyst, Available Carbohydrate Dietary Fiber and Association of Official Analytical Chemists (AOAC) Method 991.43 methods. CL waxy and normal maize starch granules swelled much more at higher temperatures, resulting in significantly lower total dietary fiber content than high-amylose maize starch. The alkali treatment study on low levels of cross-linking in starch affected the ratios of total bound phosphate esters which changed the degree of starch swelling, crytallinity and pasting properties of the CL starch. The study on the mechanism of the digestive enzymes and the extent of digestion during the incubation of CL wheat starch in AOAC Method 2009.01 showed progressive digestion after 16 h of incubation, which may not reflect in-vivo response in human. Extrusion of normal and waxy wheat flours resulted in the breakdown of starch and an increase in the insoluble protein, which affected the textural and structural properties of extrudate. High energy input played a major role in radial expansion of normal hard wheat extrudate, whereas higher amylopectin in soft waxy wheat flour was a dominant factor in determining the radial expansion when compared to normal soft wheat. Inclusion of soft waxy wheat in the oat flour formulations at 18% moisture content improved the textural and structural properties of extrudates. Low cross-linking level of CL waxy maize starch in oat flour formulation increased the void fraction and reduced the breaking strength of extrudates, whereas higher cross-linking levels of CL starches improved the resistant starch level on oat flour formulation but had very poor structural and textural properties.The study offers a good insight on the properties and digestibility of CL starch, as well as using low levels of CL starch to improve textural properties of nutritional extruded products. In addition, study on the extrusion of wheat flours with different amylose and protein contents provides knowledge on the influence of chemical compositions and energy input on the physico-chemical properties of extrudates.

Master of Science / Department of Diagnostic Medicine/ Pathobiology / Lisa M. Pohlman / Background: Iron storage disease has proven to be a serious health concern for captive toucans. Physiologic mechanisms to efficiently extract iron from naturally iron-deficient diets appear the likely cause of iron overload when fed iron-sufficient diets in captivity. Iron overload can result in diabetes, heart failure, and even death. Serum ferritin concentrations are considered the most reliable screening tool to predict total body iron stores in many species, but an assay has not been available to measure serum ferritin in toucans. Objective: The purpose of this study was to develop an enzyme-linked immunosorbent assay (ELISA) to measure serum ferritin in toucans using a polyclonal antibody in a sandwich arrangement. Methods: Ferritin was isolated from toucan liver and used as a standard. A rabbit polyclonal anti-toucan antibody was used as the capture antibody and as a detection antibody conjugated to horseradish peroxidase. Linearity of toucan ferritin standards, effect of serum dilution, recovery of added ferritin standards, and intra- and inter-assay variability were determined. Results: Ferritin standards were linear from 0 to 50 ng/ml. The relationship between serum dilution and serum ferritin concentration was also linear. When 10, 20, 30, 40, or 50 ng/ml of purified toucan ferritin were added to diluted serum, the recoveries varied from 69% to 104%. The intra-assay variability for four test serum samples averaged 11% and the inter-assay variability for the same four samples averaged 11%. Conclusions: Although the results from the linearity and recovery studies are promising for assay development when viewed independently, preliminary ferritin concentrations from all toucans studied are much higher than expected. Upon further evaluation including Dot blot assays, Western blot assays, SDS-PAGE, and protein determination of the ferritin stock solution, it was determined that the ferritin stock solution did not contain a pure protein and therefore likely renders the assay invalid. Further testing is needed to confirm these findings.

Condition monitoring (CM) of electrical equipment is an important field in electrical engineering and a considerable amount of research is dedicated to this field. Power cables are one of the most important parts of any electrical network and the variety of techniques available for CM of electrical cables is therefore no surprise. Electrical cables are exposed to operational and environmental stressors which will cause degradation of the insulation material. The degradation will continue to the point where the cable fails. Blackouts caused by failing cables will have an effect on the safety, efficiency and production of an electrical network. It is therefore important to constantly monitor the condition of electrical cables, in order to prevent the premature failure of cables. The research presented in this dissertation sets out to investigate CM techniques for power cables and to design and implement a basic cable CM technique based on the principles of partial discharge (PD) measurements. A comprehensive literature study introduces the fundamental concepts regarding the CM of power cables. The basic construction of electrical cables, as well as the variety of different types is researched in order to lay a foundation for the research that follow. CM techniques for electrical equipment are investigated, with the emphasis on techniques used on cables. Conducted research led to the decision to focus on CM by means of PD measurements. PD as a phenomenon is investigated to be able to better understand the origins and effects of discharge activity. From there the focus shifts to the available techniques for monitoring the condition of electrical cables by means of PD measurements. The research conducted in the literature study chapter forms the basis from which the rest of the study is conducted. Simulation models were used to study PD characteristics. The models are derived from engineering and mathematical principles and are based on the well-known three-capacitor model of PD. The simulations were performed in order to study the effects of discharge activity. The designed simulation models allows for a variety of PD characteristics to be studied. The simulations were performed in the MATLAB® Simulink® environment. The research conducted in the dissertation was used to design an elementary CM technique which can be used to detect the presence of PD within electrical cables. The designed CM technique was used for the practical measurement of PD data. MATLAB® programs were designed in order to analyse the PD data in both the time- and frequency-domain. The analysis of the measured data revealed PD characteristics of the test specimen used for the measurements. The designed CM is used for the detection of PD activity within electrical cables and in combination with other techniques, may be used for complete CM of electrical cables. The experimental setup which was used to take practical PD measurements adds another dimension to the work presented in this dissertation. / MIng (Electrical and Electronic Engineering), North-West University, Potchefstroom Campus, 2015

Condition monitoring (CM) of electrical equipment is an important field in electrical engineering and a considerable amount of research is dedicated to this field. Power cables are one of the most important parts of any electrical network and the variety of techniques available for CM of electrical cables is therefore no surprise. Electrical cables are exposed to operational and environmental stressors which will cause degradation of the insulation material. The degradation will continue to the point where the cable fails. Blackouts caused by failing cables will have an effect on the safety, efficiency and production of an electrical network. It is therefore important to constantly monitor the condition of electrical cables, in order to prevent the premature failure of cables. The research presented in this dissertation sets out to investigate CM techniques for power cables and to design and implement a basic cable CM technique based on the principles of partial discharge (PD) measurements. A comprehensive literature study introduces the fundamental concepts regarding the CM of power cables. The basic construction of electrical cables, as well as the variety of different types is researched in order to lay a foundation for the research that follow. CM techniques for electrical equipment are investigated, with the emphasis on techniques used on cables. Conducted research led to the decision to focus on CM by means of PD measurements. PD as a phenomenon is investigated to be able to better understand the origins and effects of discharge activity. From there the focus shifts to the available techniques for monitoring the condition of electrical cables by means of PD measurements. The research conducted in the literature study chapter forms the basis from which the rest of the study is conducted. Simulation models were used to study PD characteristics. The models are derived from engineering and mathematical principles and are based on the well-known three-capacitor model of PD. The simulations were performed in order to study the effects of discharge activity. The designed simulation models allows for a variety of PD characteristics to be studied. The simulations were performed in the MATLAB® Simulink® environment. The research conducted in the dissertation was used to design an elementary CM technique which can be used to detect the presence of PD within electrical cables. The designed CM technique was used for the practical measurement of PD data. MATLAB® programs were designed in order to analyse the PD data in both the time- and frequency-domain. The analysis of the measured data revealed PD characteristics of the test specimen used for the measurements. The designed CM is used for the detection of PD activity within electrical cables and in combination with other techniques, may be used for complete CM of electrical cables. The experimental setup which was used to take practical PD measurements adds another dimension to the work presented in this dissertation. / MIng (Electrical and Electronic Engineering), North-West University, Potchefstroom Campus, 2015

A quantitative competitive binding "triple sandwich" enzyme immunoassay was used to evaluate pathogen/class-specific antibody responses in Holstein-Friesian calves vaccinated against Clostridium perfringens B-toxin at various ages postpartum. Vaccination of dams at six weeks and again at two weeks prepartum increased pathogen-specific antibody levels in their colostrum and respective calf's serum. Calves initially vaccinated at three days produced both a primary and secondary pathogen-specific antibody response, whereas calves initially vaccinated at 12 and 21 days produced only secondary responses. Maternally-derived antibodies were found to suppress neonatal antibody production following primary immunization. They were also found to influence secondary humoral immune responses, although in a diminished capacity. Pathogen-specific IgG and IgM concentrations in dams' sera and colostra were found related to subsequent pathogen-specific IgG and IgM neonatal serum concentrations. Only pathogen-specific IgA in dams' colostra was correlated to neonatal levels, possibly owing to a different origin and role of this immunoglobulin class. All class-specific colostral immunoglobulin levels were related to subsequent neonatal concentrations. Based on results from this experiment, it is recommended that calves be vaccinated at three days postpartum with a booster administered at 63 days.