Faculty of Science School of Geography,Archaeology and Enviromental Studies 0310392a smami2003@yahoo.co.uk / Points are often the most abundant retouched lithics in MSA collections yet very little research has been done on their functions, especially in southern Africa where it has always been assumed that points were spears. This paper reports on the results of a technological analysis of two types of points from Rose Cottage Cave, South Africa. The study aims at examining the possibility that thick, broad points from various post-Howiesons Poort layers dating between 50 000 and 28 000 years ago were used as spearheads that were thrust at prey, while the narrow, thin points from one of the final MSA layers, Dc, (between 31 000 and 29 000 years old), were used as arrowheads that may have transported poison to prey. The results indicate that the former type of points were more likely to have been used as spearheads while the latter type were more likely to have been arrowheads.

In this dissertation we investigate Lagrange interpolation. Our first result will deal with a hierarchy of interpolation schemes. Specifically, we will show that given a triangular array of points in a regular compact set K, such that the corresponding Lebesgue constants are subexponential, one always has the uniform convergence of Ln(f) to f for all functions analytic on K. We will then show that uniform convergence of Ln(f) to f for all analytic functions f is equivalent to the fact that the probability measures γn = 1/n Σn j=1 δzn,j , which are associated with our triangular array, converge weak star to the equilibrium distribution for K. Motivated by our hierarchy, we will then come to our main result, namely that the Lebesgue constants associated with Leja sequences on fairly general compact sets are subexponential. More generally, considering Newton interpolation on a sequence of points, we will show that the weak star convergence of their corresponding probability measures to the equilibrium distribution, together with a certain distancing rule, implies that their corresponding Lebesgue constants are sub-exponential.

Little is known about the time depth of human occupation in the Tualatin Valley. Archaeological investigations have produced no absolute dates for the few sites tested. Projectile points collected from the Ibach and Heynderickx farms in the Tualatin Valley show similarities to early point styles from sites in the Pacific Northwest dating from 6,000 to 10,000 years ago. To determine how old the Ibach and Heynderickx sites are, the undated collections of 107 Ibach points and 119 Heynderickx points are compared to two established chronological projectile point sequences, which had been constructed using the relative dating technique of frequency seriation. These sequences are further anchored with radiocarbon dates which extend back 6,000 years. On the basis of the comparison of Ibach and Heynderickx projectile point types to the seriated point types, it is suggested that the Tualatin Valley sites evidence occupation times at least as early as 6,000 years ago and possibly earlier.

In this thesis we study projective perspective on planar euclidean geometry. First we take an euclidean construction and transform it into the projective language. Then we discover and show principles of this transformation. We show equivalence between complex points I, J and some euclidean structures. Moreover we study conics, triangles, polygons and circles. We build this thesis on examples. 1

Un proyecto de construcción tiene como principales objetivos la rentabilidad y la obtención de utilidad. En la actualidad, en edificaciones de gran altura estos vienen siendo afectados por exceso de consumo de material no planificado, es decir el sobredesperdicio. La presente tesis tiene como finalidad analizar y darle seguimiento al flujo interno de dos de los materiales más incidentes en la construcción de una edificación: cemento y cerámico, con el fin de plantear como propuesta de mejora un procedimiento de trabajo que beneficie a la reducción de los sobredesperdicios. La metodología que se utilizó para obtener los datos del análisis consistió en el método de investigación de campo, dado que la recolección de datos se llevó a cabo directamente de tres proyectos de edificación mayor a los quince pisos de altura ubicados en la ciudad de Lima Metropolitana. Se hizo un análisis y seguimiento al flujo de distribución del material y de esta manera se obtiene, resultados que permiten determinar el problema raíz para poder analizarlo e implementar la mejor alternativa para reducir o eliminar estos factores que conllevan al aumento del desperdicio. Se concluye que las causas críticas o principales de estos sobredesperdicios son la falta de seguimiento, planificación, gestión y comunicación que se da en la mayoría de empresas constructoras. Luego de un análisis se establece un procedimiento de trabajo destinado al desarrollo de una actividad con el objetivo principal de disminuir los sobredesperdicios de los materiales identificados en su flujo de distribución. / A construction project has as its main objectives the profitability and the obtaining of utility. Currently, in high-rise buildings these are being affected by excess consumption of unplanned, over-wasted material. The purpose of this thesis is to analyze and monitor the internal flow of two of the most incidental materials in the construction of a building, cement and ceramic, in order to propose as a proposal for improvement a work procedure that benefits the reduction of the over-waste. The methodology that was used to obtain the data of the analysis consisted of the field research method, given that the data collection was carried out directly from three building projects greater than fifteen floors high located in the city of Metropolitan Lima An analysis and monitoring of the distribution flow of the material was made and, in this way, results are obtained that allow the root problem to be determined in order to analyze it and implement the best alternative to reduce or eliminate these factors that lead to an increase in waste. It is concluded that the critical or main causes of these over-waste are the lack of monitoring, planning, management and communication that occurs in most construction companies, thereby establishing a work procedure for the development of an activity with the main objective to reduce the over-waste of the materials identified in its distribution flow. / Tesis

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With the rapid development of digital multimedia and internet techniques in the last few years, more and more digital images are being distributed to an ever-growing number of people for sharing, studying, or other purposes. Sharing images digitally is fast and cost-efficient thus highly desirable. However, most of those digital products are exposed without any protection. Thus, without authorization, such information can be easily transferred, copied, and tampered with by using digital multimedia editing software. Watermarking is a popular resolution to the strong need of copyright protection of digital multimedia. In the image forensics scenario, a digital watermark can be used as a tool to discriminate whether original content is tampered with or not. It is embedded on digital images as an invisible message and is used to demonstrate the proof by the owner. In this thesis, we propose a novel localized geometric-distortion resilient digital watermarking scheme to embed two invisible messages to images. Our proposed scheme utilizes two complementary watermarking techniques, namely, local circular region (LCR)-based techniques and block discrete cosine transform (DCT)-based techniques, to hide two pseudo-random binary sequences in two kinds of regions and extract these two sequences from their individual embedding regions. To this end, we use the histogram and mean statistically independent of the pixel position to embed one watermark in the LCRs, whose centers are the scale invariant feature transform (SIFT) feature points themselves that are robust against various affine transformations and common image processing attacks. This watermarking technique combines the advantages of SIFT feature point extraction, local histogram computing, and blind watermark embedding and extraction in the spatial domain to resist geometric distortions. We also use Watson’s DCT-based visual model to embed the other watermark in several rich textured 80×80 regions not covered by any embedding LCR. This watermarking technique combines the advantages of Harris feature point extraction, triangle tessellation and matching, the human visual system (HVS), the spread spectrum-based blind watermark embedding and extraction. The proposed technique then uses these combined features in a DCT domain to resist common image processing attacks and to reduce the watermark synchronization problem at the same time. These two techniques complement each other and therefore can resist geometric and common image processing attacks robustly. Our proposed watermarking approach is a robust watermarking technique that is capable of resisting geometric attacks, i.e., affine transformation (rotation, scaling, and translation) attacks and other common image processing (e.g., JPEG compression and filtering operations) attacks. It demonstrates more robustness and better performance as compared with some peer systems in the literature.

The growing market of portable devices and smart wearables has contributed to innovation and development of systems with longer battery-life. While Near Threshold Computing (NTC) systems address the need for longer battery-life, they have certain limitations. NTC systems are prone to be significantly affected by variations in the fabrication process, commonly called process variation (PV). This dissertation explores an intriguing effect of PV, called choke points. Choke points are especially important due to their multifarious influence on the functional correctness of an NTC system. This work shows why novel research is required in this direction and proposes two techniques to resolve the problems created by choke points, while maintaining the reduced power needs.

Since pastoralism began in Australia???s rangelands, the number of artificial watering points (AWPs) has increased dramatically, such that today, few areas of rangeland are further than 10 km from water. This increased availability of water has caused many ecological impacts. Unfortunately, such impacts are poorly understood in the context of an Australian conservation reserve, thus hindering strategic management. This study examined the spatial distribution of vertebrate (kangaroos, small mammals, lizards and avifauna) and vegetative variables around open AWPs as well as AWPs that have been closed since pastoralism (sheep-grazing) ceased nearly thirty years ago in Sturt National Park, arid New South Wales. The study also examined vertebrate use of AWPs, with a particular emphasis on kangaroos and avifauna. The study revealed that most variables showed few differences in spatial distribution with distance from open and closed AWPs, thus suggesting that the observed piospheric impacts were primarily attributable to historical sheep-grazing. Indeed, piospheric patterns were weak suggesting some recovery over the last thirty years. That kangaroos did not exhibit water-focused grazing is no surprise, since despite their regular use of AWPs, particularly during hot, dry times, the current spatial arrangement of AWPs facilitates regular travel to, and from, such resources allowing kangaroos, like much other fauna, to distribute themselves in relation to food and shelter preferences rather than in relation to water supply. In contrast, the majority of avifaunal groups (excluding ground-dwelling species) were clustered around open AWPs, often irrespective of season, because of food and water requirements. Such spatial concentrations of avifauna are thought to cause a range of interspecific effects. Experimental AWP closure and GIS modelling showed that whilst closure of AWPs will increase the average distance to water, which will have key benefits, the majority of areas in Sturt National Park would still be accessible to most water-dependent species even if all unused AWPs were closed. Strategic retention of AWPs to replace water sources lost since European settlement, aid threatened and migratory species??? conservation and enhance nature-based tourism opportunities is thus recommended and an example of a strategic management and monitoring plan outlined.

Sur les espaces de modules de différentielles abéliennes existe une action naturelle de SL(2,R). Ses orbites, appelées disques de Teichmüller, se projettent dans les espaces de modules de surfaces de Riemann sur des géodésiques complexes. En tirant en arrière la forme dz du tore standard par des revêtements ramifiés au-dessus d'un seul point, on obtient les surfaces à petits carreaux, points entiers des espaces de modules de différentielles abéliennes. Nous étudions en détail les disques de Teichmüller des points entiers de l'espace des modules des différentielles abéliennes en genre deux avec un zéro double: nombre de disques de Teichmüller pour chaque nombre de carreaux, et leur géométrie; propriétés algébriques des stabilisateurs (sous-groupes de SL(2,Z) qui ne sont pas de congruence); comportement asymptotique des constantes de Siegel-Veech (coefficients des taux de croissance quadratiques des géodésiques fermées) lorsque le nombre de carreaux tend vers l'infini.