Magister Educationis - MEd / The study is located within the project: Relevance of School Mathematics Education (ROSME) of the Department of Didactics at the University of the Western Cape. The research is undertaken in the belief that Mathematics enables creative and logical reasoning about contextualised problems in the realm of the physical and social world as well as in the discipline mathematics itself. Relevance of school Mathematics has the implied notion of contextual issues. This research attempts to investigate the contextual issues that teachers have to deal with in Mathematics education. Given the results of the TIMMS report, this research aims to investigate, through comparison, the context preferences between a selected group of practicing teachers in South Africa and those of their counterparts in South Korea.

>Magister Scientiae - MSc / The study of neutral atomic hydrogen (HI) plays a vital role in improving the knowledge about galaxy evolution since HI serves as the raw fuel for star formation. However, the current knowledge about it is limited to the nearby Universe due to its intrinsic faintness and the inadequate sensitivities of the current radio telescopes.

As smartphone technology continues to evolve, it begs the question as to whether or not smartphones could be used by crime scene investigators. Crime scene documentation is a time-consuming task when using a standard tape measure compared to advanced techniques (such as 3D scanners). However, these advanced techniques are expensive and take time to set up. Measurement applications could potentially serve as an affordable and sufficient alternative. Therefore, it’s important to understand how accurate these applications are as well as how well they work for measuring crime scenes and forensic evidence. Eleven measurement applications were downloaded (onto an Apple iPhone XR) and evaluated and then narrowed down to four applications to be used in this study. Several parameters were assessed in all eleven applications. Factors such as tools available, effective maximum distance, ease of use, and accuracy were tested. The applications that best met all criteria were used for this study. First, the applications were used to measure several known dimensions such as a ruler, then they were used to measure room dimensions, outdoor scenes, footwear impressions, and bloodstains. Accuracy was assessed by comparing the results from the applications to the measurements made from a standard tape measure or ruler. Standard deviation of all measurements was calculated and compared against one another. Feasibility was evaluated by recording the amount of time that it took to conduct the measurements and comparing the times to one another. Adaptability to various environments was also factored in when evaluating feasibility. Overall, the applications Tape Measure and MagicPlan were found to be the most accurate and feasible applications to use for crime scene measurements. Moasure was found to be the least efficient and precise application in this study. Measure, Moasure, MagicPlan, and Tape Measure serve as an affordable, fast, and easy presumptive tool for crime scene documentation. In the future, these applications could be used to document crime scenes, and could assist particular agencies with insufficient monetary resources. While the applications selected (Measure, Moasure, MagicPlan, and Tape Measure) proved to be accurate, additional tests should be conducted before being implemented exclusively by investigators. With continual progression in modern technology, substantial improvements are anticipated that encompass these smartphone applications, which will increase reliability as it relates to forensics.

Many different types of features can appear on the surface of wooden boards, lineals or parts. Some of these features should not appear on the surfaces of wood products. These features then become undesirable or removable defects for those products. To manufacture these products boards are cutup in such a way that these undesirable defects will not appear in the final product. Studies have shown that manual cutup of boards does not produce the highest possible yield of final product from rough lumber. Because of this fact a good deal of research work has been done to develop automatic defect detection systems. Color images contain a lot of valuable information which can be used to locate and identify features in wood. This is evidenced by the fact that the human color vision system can accurately locate and identify these features. A very important part of any automatic defect detection system based wholly or impart on color imagery is the location of areas that might contain a wood feature, a feature that depending on the product being manufactured may or may not be a defect. This location process is called image segmentation. While a number of automatic defect detection systems have been proposed that employ color imagery, none of these systems use color imagery to do the segmentation. Rather these systems typically average the red, green, and blue color channels together to form a black and white image. The segmentation operation is then performed on the black and white image. The basic hypothesis of this research is that the use of full color imagery to locate defects will yield better segmentation results than can be obtained when only black and white imagery is used. To approach the color wood image segmentation problem, two conventional clustering procedures were selected for examination. Experiments that were performed clearly showed that these procedures, ones that are similar in flavor to other unsupervised clustering methods, are unsuitable for wood color image segmentation. Based on the experience that was gained in examining the unsupervised clustering procedures, a model based approach is developed. This approach is based on the assumption that the distribution of colors in clear wood is Gaussian. Since boards that are used by the forest products secondary manufacturing industry are all such that most of their surface area is clear wood, the idea is to use the most frequently occurring colors, i.e., the ones that must represent the most likely colors of clear wood, to estimate the mean and covariance of the Normal density function specifying the possible colors of clear wood. Deviations from this model in the observed histogram are used to identify colors that must be caused by features other than clear wood that appear on the surface of the board. / Master of Science

Because of the latest developments in nanotechnology and the need to have new functions, a high demand for innovative materials is created. The technological requirements for new applications cannot be fulfilled by most of the well-developed materials like metals, plastics, or ceramics. Therefore, composite materials that can exhibit better properties in contrast to their single counterpart represents a valuable and interesting alternative for the development of new and more performing functional materials. In the past few years, one of the most rapidly developing fields in materials chemistry is research and development of innovative hybrid materials and nanocomposites having exceptional properties. A significant reason for this is that this group of materials closes the gaps between different scientific fields and brings together the ideal properties of the different disciplines into a single system. Conventional materials like polymers or minerals can be mixed with substances of a different kind, like biological molecules and different chemical functional groups to create unique functional materials with the help of a building block method. Inorganic and organic chemistry, physical and biological sciences are integrated in the search for new recipes in a purely interdisciplinary way to generate unique materials. Compounds that are created frequently have interesting new properties for forthcoming functional materials and technological applications. Natural materials frequently function as a model for these systems and various examples of biomimetic methods can be obtained while generating these hybrid materials. The research and development of these materials is driven by the needs of future technologies. The research carried out in this thesis is entirely based on hybrid organic-inorganic materials; hence, it consists of soft organic/bioorganic section that makes it possible to generate multifunctional materials, whereas the hard inorganic section functions as a rigid and stable platform for developing nanocarriers and imaging agents. A key domain in materials chemistry is the creation of smart materials that have the ability to respond to environmental changes or be triggered on demand. These materials have led to the creation of new technologies, like electroactive materials, electrochromic materials, biohybrid materials, sensors and membranes, etc. The required functionality can be provided by the organic or inorganic components, or from both. In this dissertation, the synthesis, methodology, and creation of three unique organic-inorganic hybrid stimuli responsive systems having targeted features for specific applications are examined. The first example is represented by supramolecular microtoroids created by spontaneous self-assembly of amphiphilic molecules and a hydrophilic polymer (chitosan), in the presence of iron (III) chloride. Light irradiation is the stimulus responsible for assembly/disassembly of this new supramolecular entities. The basis of the photo-response of the microtoroids is the photoreaction of the anthracene derivatives. In order to make these materials bio applicable, the microtoroid size was controlled and narrowed down to nanometers, which has led to our second system called metal organic complexes (MOCs). In this system, chitosan was replaced by PNIPAM polymer at optimized concentrations. The reversible thermo-response of MOCs comes from the phase transition ability of PNIPAM. The third hybrid material is the core-shell system consisting of mesoporous organosilica coated with iron oxide nanoparticles, used for cargo delivery and cell imaging. The magnetic-response of the core-shell system results from the strong magnetic properties of iron oxide nanoparticles, while the presence of PMOs increased its biocompatibility. Our research on such organic-inorganic hybrid materials represents a promising development in the field of materials chemistry. Due to the possibility of mixing various properties in a single material, a variety of combinations regarding possible materials and applications have emerged.

Cuando una startup sale al mercado, se enfoca en crecer exponencialmente, utilizando una idea innovadora y un presupuesto relativamente bajo. Este crecimiento exponencial se apoya en la tecnología, la cual debe manejar un rendimiento adecuado en los recursos de hardware para los servicios, acorde con el giro del negocio. El objetivo principal de este trabajo es realizar un análisis de una plataforma para aplicaciones web con una arquitectura basada en contenedores, que sea capaz de soportar el crecimiento exponencial de usuarios de sus servicios Web. Las arquitecturas tradicionales basadas en servidores físicos implican tiempos y costos de configuración, despliegue y mantenimiento que son altos. Cuando se hace necesario escalar, se requiere, normalmente, de más recursos de hardware y de tiempo para realizar las configuraciones necesarias. La flexibilidad que provee la virtualización de servidores agiliza los procedimientos de escalamiento y reduce considerablemente el tiempo y los costos, comparados con las soluciones basadas solamente en hardware. Sin embargo, para atender requerimientos más exigentes, la virtualización tiene una huella muy pesada y tiempos de despliegue todavía elevados. La tecnología de contenedores nos ofrece una plataforma liviana y eficiente. Un contenedor es un paquete ejecutable muy liviano que aísla una pieza de software, incluyendo todo lo necesario para ser ejecutado. Está claro que la velocidad y la eficiencia son las mayores necesidades para las startups, y Docker, uno de los líderes en el mercado de contenedores de software, es capaz de proporcionarlas de manera efectiva. Si bien es cierto no ha reemplazado a las máquinas virtuales, se está notando el potencial de Docker. Eso no quiere decir que las máquinas virtuales quedaran obsoletas, por el contrario, Docker y las máquinas virtuales coexistirán uno al lado del otro, dando a los startups más opciones para ejecutar sus aplicaciones en la nube. / When a startup goes to market, it focuses on growing exponentially, using an innovative idea and a relatively low budget. This exponential growth is supported by technology, which must handle adequate performance in the hardware resources for services, in accordance with the line of business. The main objective of this work is to carry out an analysis of a platform for web applications with a container-based architecture, which is capable of supporting the exponential growth of users of its Web services. Traditional physical server-based architectures involve high configuration, deployment, and maintenance times and costs. When scaling becomes necessary, it usually takes more hardware and time to complete the necessary configurations. The flexibility that server virtualization provides streamlines escalation procedures and greatly reduces time and cost, compared to hardware-only solutions. However, to meet more demanding requirements, virtualization has a very heavy footprint and still high deployment times. Container technology offers us a lightweight and efficient platform. A container is a very lightweight executable package that isolates a piece of software, including everything needed to be run. It is clear that speed and efficiency are the greatest needs for startups, and Docker, one of the leaders in the software container market, is capable of providing them effectively. While it's true it hasn't replaced virtual machines, Docker's potential is being noticed. That doesn't mean that virtual machines will become obsolete, on the contrary, Docker and virtual machines will coexist side by side, giving startups more options to run their applications in the cloud. / Tesis

The first objective of this research project is to carry out multi-objective optimization (MOO) for four simple chemical engineering processes to clearly demonstrate the wealth of information on a given process that can be obtained from the MOO instead of a single aggregate objective function. The four optimization case studies are the design of a PI controller, an SO2 to SO3 reactor, a distillation column and an acrolein reactor. Results that were obtained from these optimization case studies show the benefit of generating and using the Pareto domain to gain a deeper understanding of the underlying relationships between the various process variables and the different performance objectives. In addition, an acrylic acid production plant model is developed in order to propose a methodology to solve multi-objective optimization for the two-reactor system model using artificial neural networks (ANNs) as metamodels, in an effort to reduce the computational time requirement that is usually very high when first-principles models are employed to approximate the Pareto domain. Once the metamodel was trained, the Pareto domain was circumscribed using a genetic algorithm and ranked with the Net Flow method (NFM). After the MOO was carry out with the ANN surrogate model, the optimization time was reduced by a factor of 15.5.

Remote sensing enables the acquisition of large amounts of data, over a small period of time, in support of many ecological applications (i.e. precision agriculture, vegetation mapping, etc.) commonly from satellite or manned aircraft platforms. This dissertation focuses on using small unmanned aerial systems (UAS) as a remote sensing platform to collect aerial imagery from commercial-grade cameras and as a radio localization platform to track radio-tagged sh. The small, low-cost nature of small UAS enables remotely sensed data to be captured at a lower cost, higher spatial and temporal resolution, and in a more timely manner than conventional platforms. However, these same attributes limit the types of cameras and sensors that can be used on small UAS and introduce challenges in calibrating the imagery and converting it into actionable information for end users. A major contribution of this dissertation addresses this issue and includes a complete description on how to calibrate imagery from commercial-grade visual, near-infrared, and thermal cameras. This includes the presentation of novel surface temperature sampling methods, which can be used during the ight, to help calibrate thermal imagery. Landsat imagery is used to help evaluate these methods for accuracy; one of the methods performs very well and is logistically feasible for regular use. Another major contribution of this dissertation includes novel, simple methods to estimate the location of radio-tagged sh using multiple unmanned aircraft (UA). A simulation is created to test these methods, and Monte Carlo analysis is used to predict their performance in real-world scenarios. This analysis shows that the methods are able to locate the radio-tagged sh with good accuracy. When multiple UAs are used, the accuracy does not improve; however the sh is located much quicker than when one UA is used.

The design process is important to all landscape architects. It helps generate ideas to solve problems in an efficient amount of time and insure that all stages of a project are completed. Generally, a design process includes project acquisition, inventory and site analysis, conflicts identification, public involvement, draft products, and final presentation. Among these elements, public involvement has been recognized as one of the most important elements in the landscape design process. It not only helps professionals get projects done smoothly, but it also helps with long-term client retention. Traditional two-dimensional communication methods using renderings, design plans, and maps have not been fully successful in their ability to engage and sufficiently inform clients and stakeholders. While professional planners are able to rely on their experience to help them visualize proposed landscapes, the average client is often overwhelmed by the relatively complex and abstract information, and unable to translate this information into landscape visions. Developments in the field of 3D graphics have dramatically extended possibilities to overcome this barrier by providing a tool that produces designs that are easy to comprehend and helps clients better visualize the end product that the designer has put forth. Some people argue that the high investment cost of 3D software such as ArcGIS, 3Dmax, etc., and its time-consuming process to master, is too great an obstacle for most designers and firms to use the software in their work with the average client or stakeholder. However, little research has been done to investigate the extent to which landscape architects have adopted the 3D software. We know even less about their opinions on the suitability of existing 3D software packages to meet their professional needs. A nationwide survey about current use and future demand for 3D simulation software within the landscape profession was conducted for this thesis. Comprehensive online surveys were sent to two groups: (1) landscape architecture firms and freelance landscape architects; and (2) institutions with landscape architecture programs. In total, 3,434 firms and freelance architects were identified based on data from the American Society of Landscape Architecture. Names and contact information of ninety-one faculty members from institutions with landscape architecture programs were found on the Council of Educators in Landscape Architecture website. The opportunities and challenges of 3D visualization technology and its potential applications in landscape and environmental planning have been examined based on the findings from survey results. The results are relevant to the future improvement and innovation of 3D visualization software in the landscape architecture profession and can assist landscape architecture educators with future curriculum development.

This dissertation describes the development and analysis of a new forest dynamics model. The NORTHern Woodland Dynamics Simulator (NORTHWDS) was designed to spatially model forest pattern and process for the northern Lake States, and to incorporate multiple spatial scales. While ecologically detailed, this stand table-based model is sufficiently parsimonious to be able to simulate 100s to 1000s of hectares for centuries. Processes like tree regeneration, growth, and mortality, herbaceous and shrubby competition, biogeochemistry, carbon cycling, edge effects, and climatic influences are incorporated in NORTHWDS. Wind disturbance and white-tailed deer browsing were also included to help forecast stand and landscape dynamics under managed and unmanaged scenarios. Preliminary results suggest that NORTHWDS can reliably predict long-term forest ecosystem responses to succession and disturbance. NORTHWDS was also applied to test the effectiveness of a managing-for-old-growth strategy, with results indicating that this type of management can provide improvements over traditional even- and uneven-aged harvest systems in desirable old-growth attributes like aboveground live biomass and coarse woody debris patterns. The results of the NORTHWDS developmental and application chapters were then synthesized to produce a new conceptual approach to landscape simulation that incorporated space, multiple scales, and a hierarchical design. A user's guide, the source code, and model defaults complete this dissertation.