The purpose of the study was to determine the accuracy of 11 prediction equations in estimating the 1 repetition maximum (1RM) bench press from repetitions completed by collegiate football players (N = 69) using 225 lb. The demographic variables race, age, height, weight, fat-free weight, and percent body fat were measured to determine whether these variables increased the accuracy of the prediction equations; race was the most frequently selected variable in the regression analyses. The validity of the prediction equations was dependent upon the number of repetitions performed, i.e., validity was higher when fewer repetitions were completed. Explained variability of 1RM was slightly higher for all 11 equations when demographic variables were included. A new prediction equation was also developed using the number of repetitions performed and the demographic variables height and fat-free weight.

In this thesis, ties and time-varying covariates in survival analysis are investigated. There are two types of ties: ties between event times (Type 1 ties) and ties between event times and the time that discrete time-varying covariates change or "jump"(Type 2 ties). The Cox proportional hazards model is one of the most important regression models for survival analysis. Methods for including Type 1 ties and time-varying covariates in the Cox proportional hazards model are well established in previous studies, but Type 2 ties have been ignored in the literature. This thesis discusses the effect of Type 2 ties on Cox's partial likelihood, the current default method to treat Type 2 ties in statistical packages SAS and R (called Fail before Jump in this thesis), and proposes alternative methods (Random and Equally Weighted) for Type 2 ties. A simulation study as well as an analysis of data sets from real research both suggest that both Random and Equally Weighted methods perform better than the other two methods. Also the effect of the percentages of Type 1 and Type 2 ties on these methods for handling both types of ties is discussed. / NSERC

Diploma thesis includes information about percentages, mathematical olympiad, mathematical corresponding seminars and PISA ant TIMSS tests. The first, theoretical part describes historical development of mathematical olympiad and its organization, the history of mathematical corresponding seminars and list of current seminars for primary school students. The second part of the diploma thesis consists of the collection of tasks examples with percentages that appear in mathematical olympiad, mathematical corresponding seminars and PISA and TIMSS tests.

One of the major challenges in earth sciences and mineral exploration has been to determine with high accuracy and at a fast rate the elemental composition as well as the general chemistry of a rock sample. Many analytical techniques e.g., scanning electron microscopy (SEM) have been employed in the past with a certain degree of success, but their analyses usually require a lengthy sample preparation and time-consuming measurements which produce results at a much slower rate than techniques whichrequire less or do not require any sample preparation at all. SEM images the surface of a sample by scanning it with a high-energy beam of electrons in a raster scan pattern, where the primary electron beam produced under very low air pressure vacuum scans across the sample by striking it, and a variation of signals produce an image of the surface, or its elemental composition together with energy dispersive X-rays. Alternatively, laser induced breakdown spectrometry (LIBS) and multi energy X-ray transmission (ME-XRT) are non-contact measurement scanning techniques, capable of producing faster results than SEM-EDS which makes them suitable for real time measurements and analyses as they do not slow down the pace of a project being carried out. LIBS is a spectroscopic technique used to characterize and detect materials where a highly energetic laser pulse is focused onto the surfaces of solids, liquids or gases resulting in atomic and molecular species to emit light at specific wavelengths which is collected with a spectrometer and analysed using a computer. Comparably, ME-XRT is a sensor-based sorting technique involving the planar projection of X-ray attenuation of a particle stream, distributed on a fast conveyor belt, where they are scanned and evaluated while passing and an image is recorded by a line scan detector.      Eleven rock samples were analysed in this study. They include four rock type samples: granite, basalt, sandstone, and gneiss, all obtained from Luleå University of Technology (LTU) sample storage and seven ore type samples which include a porphyry Cu sulphide ore, a porphyry Cu oxide ore, a porphyry Cu-Au-Ag ore, an apatite iron ore (AIO), an iron-oxide copper gold ore (IOCG), an orogenic gold ore and a volcanogenic massive sulphide ore (VMS).       The SEM results give a semi-quantitative elemental composition of the rocks, which may be usedto discriminate mineralisation. Energy dispersive X-ray spectroscopy (EDS) maps may be used to identifygeological features and secondary electron (SE) images may be used to understand the topography of the rock samples. The SEM has a low penetration depth rate but produces moderate to high accuracy resultsdepending on the settings and calibrations. It requires a lengthy sample preparation, and its analytical time is often too long for routine industrial application. LIBS results also provide rock elemental compositions similar to the SEM, which may be quantitative if the same spectrometer is used for all elements and calibrated against a standard. It also produces element maps similar to the SEM-EDS maps. LIBS analyses yield high accuracy results but at a low penetration depth. There are no standard calibrations for the LIBS measurements, which limits quantification. LIBS measurements do not require any form of sample preparation. ME-XRT analyses result in rock chemical data portraying a light material fraction (aluminium-like) and a heavy material fraction (iron-like) which may be used to distinguish different rock samples based on the closeness of their effective atomic number Zeff to that of aluminium and iron respectively. It’s analysis also produces low-resolution images of the analysed rock samples. The image resolution is too low to allow interpretation of the data in the context of the structures and textures in the rock samples. It has a higher penetration depth than LIBS and SEM-EDS producing more volumetric data but with a lower accuracy in terms of the amount of information obtained. Only two elements are used for ME-XRT calibration measurements, if many elements of varying atomic numbers could be used, it would have the ability to provide a more reliable data. Samples must have a maximum and minimum thickness; thus, sample preparation is required to regulate the rock thickness.      SEM and LIBS provide element compositions of minerals and element distribution maps required by geologist in their daily activities during exploration and mining. This information can be considered the most useful obtained from all three techniques. However, LIBS analyses are faster, and its maps are of higher quality even at the same resolution as the SEM-EDS. This makes the LIBS preferable for real time measurements and analyses. Geological activities like drill core logging, mine mapping and sampling for grade control all require fast results for project continuity and LIBS is suitable for this purpose as it can keep up with the pace of these activities. SEM analytical technique provides semi-quantitative data which is more accurate than the LIBS data and thus, preferable for usage in research institutions and universities.ME-XRT can reveal information on the internal structures or different rock sample compositions. This makes it a suitable technique in distinguishing ore from waste material especially in iron ore mining and processing where the iron needs to be separated from the siliceous waste and sorting is also required prior to beneficiation to avoid equipment destruction by abrasive quartz. LIBS and ME-XRT analytical techniques complement each other in terms of analytical capabilities as LIBS has a low penetration depthrate but high accuracy results while the ME-XRT has a high penetration depth rate but low accuracy results. They are both fast scanning techniques that can be used for real time measurements and analyses and if their analytical prowess can be improved, the combination of these two fast analytical techniques may enable us to obtain high quality data and may as well be what is needed by geologists in the future.

Underachievement in Mathematics hangs over South African Mathematics learners like a dark cloud. TIMSS studies over the past decade have confirmed that South African learners‟ results (Grades 8 and 9 in 2011) remained at a low ebb, denying them the opportunity to compete and excel globally in the field of Mathematics. It is against this backdrop that the researcher investigated the meaningful understanding of the important yet challenging algebraic concept of Proportion. The theoretical as well as the empirical underpinnings of the fundamental idea of Proportion are highlighted. The meaningful learning of Algebra was explored and physical, effective and cognitive factors affecting meaningful learning of Algebra, views on Mathematics and learning theories were examined. The research narrowed down to the meaningful understanding of Proportion, misconceptions, and facilitation in developing Proportional reasoning. This study was embedded in an interpretive paradigm and the research design was qualitative in nature. The qualitative data was collected via task sheets and interviews. The sample informing the central phenomenon in the study consisted of a heterogeneous group of learners and comprised a kaleidoscope of nationalities, both genders, a variety of home languages, differing socio-economic statuses and varying cognitive abilities. The findings cannot be generalised. Triangulation of the literature review, the analysis of task sheets and interviews revealed that overall the participants have a meaningful understanding of the Proportion concept. However, a variety of misconceptions were observed in certain cases. Finally, recommendations are made to address the meaningful learning of Proportion and its associated misconceptions. It is hoped that teachers read and act on the recommendations as it is the powerful mind and purposeful teaching of the teacher that can make a difference in uplifting the standard of Mathematics in South African classrooms! / MEd (Mathematics Education), North-West University, Potchefstroom Campus, 2014

Underachievement in Mathematics hangs over South African Mathematics learners like a dark cloud. TIMSS studies over the past decade have confirmed that South African learners‟ results (Grades 8 and 9 in 2011) remained at a low ebb, denying them the opportunity to compete and excel globally in the field of Mathematics. It is against this backdrop that the researcher investigated the meaningful understanding of the important yet challenging algebraic concept of Proportion. The theoretical as well as the empirical underpinnings of the fundamental idea of Proportion are highlighted. The meaningful learning of Algebra was explored and physical, effective and cognitive factors affecting meaningful learning of Algebra, views on Mathematics and learning theories were examined. The research narrowed down to the meaningful understanding of Proportion, misconceptions, and facilitation in developing Proportional reasoning. This study was embedded in an interpretive paradigm and the research design was qualitative in nature. The qualitative data was collected via task sheets and interviews. The sample informing the central phenomenon in the study consisted of a heterogeneous group of learners and comprised a kaleidoscope of nationalities, both genders, a variety of home languages, differing socio-economic statuses and varying cognitive abilities. The findings cannot be generalised. Triangulation of the literature review, the analysis of task sheets and interviews revealed that overall the participants have a meaningful understanding of the Proportion concept. However, a variety of misconceptions were observed in certain cases. Finally, recommendations are made to address the meaningful learning of Proportion and its associated misconceptions. It is hoped that teachers read and act on the recommendations as it is the powerful mind and purposeful teaching of the teacher that can make a difference in uplifting the standard of Mathematics in South African classrooms! / MEd (Mathematics Education), North-West University, Potchefstroom Campus, 2014

Cette thèse utilise une approche de type théorie ancrée, en constituant un corpus de 252 vidéos d’informations, diffusées par Al Jazeera English, Press TV English, Euronews English et France 24 English, sur les événements du Printemps Arabe, pour apporter des réponses aux trois questions suivantes : [QR1] : Comment les institutions dominantes de l’information ont elles affecté le flux de l’information internationale pendant les événements du Printemps Arabe ? [QR2] : Comment les événements du Printemps Arabe furent représentés sous forme de reportages ? Et [QR3] : Comment les contributions à l’information ont-elles été utilisées pour construire les reportages internationaux ? Les vidéos d’informations du corpus sont étudiées à travers une Analyse Critique du Discours. Par conséquent, l’analyse est complémentée par une recherche documentaire et par une recherche empirique, sous la forme d’interviews, sur les institutions dominantes de l’information du Printemps Arabe, comprenant les chaines d’information mentionnées précédemment ainsi que l’agence de presse AFP et l’agence UGC Crowdspark. De plus, les paysages de l’information et des médias du Bahreïn, de l’Egypte, de la Libye, de l’Arabie Saoudite, de la Syrie, de la Tunisie et du Yémen, entre 2011 et 2013, ont également été étudiés à partir de recherche documentaire. Il est apparu que tous ces pays avaient des lois strictes sur l’accès à l’information et la publication, tout particulièrement quand ces informations concernaient les autorités, la religion ou la sécurité du pays, amenant des actes de censure stricts et des menaces, qui ont eux-mêmes conduit à l’autocensure chez les acteurs de l’information locaux et internationaux. Cette recherche a montré que la plupart des événements du Printemps Arabe ont été représentés en utilisant des images des lieux des événements, avec une représentation internationale minime et avec des modèles de représentation de manifestations pacifiques lors des soulèvements en Egypte, en Syrie et au Yémen et des modèles de représentation d’émeutes violentes lors des soulèvement Bahreïnis et Tunisiens. Des modèles mettant en scène la destruction ou des explosions ont pu être observés dans les pays en proie à une quelconque forme de conflit, à savoir en Libye et en Syrie. Les images de mort et de souffrance étaient peu répandues et seulement prédominantes dans les informations représentant la mort de Gaddafi et l’attaque chimique dans le Ghouta. La majorité des interviews d’information ont donné voix aux acteurs importants des événements, par opposition aux experts sur le sujet. L’analyse critique du discours a permis de formuler des théories sur l’utilisation des différents contenus dans les informations internationales, à savoir : les interviews, le contenu amateur, les chiffres et les pourcentages, les citations et le contenu de télévision publique. / This thesis uses a grounded theory approach, by building a corpus of 252 news videos, broadcast by Al Jazeera English, Press TV English, Euronews English and France 24 English, on events of the Arab Spring, to answer three questions: [RQ1] how did the dominant institutions of information affect international news flow during the events of the Arab Spring? [RQ2] how were the events of the Arab Spring represented in form of news stories? And [RQ3] how was contributed material used to construct international news stories?The news videos from the corpus are analysed using Critical Discourse Analysis, therefore the discourse analysis is complemented by literature, and empirical research in form of interviews, on the dominant information institutions of the Arab Spring, including the aforementioned news channels as well as the news agency AFP and the UGC agency Crowdspark. Additionally, the information and media landscape of Bahrain, Egypt, Libya, Saudi Arabia, Syria, Tunisia and Yemen between 2011 and 2013 has also been studied using existing literature. It was found that all countries had strict laws against information access or publication, especially if the information was related to authorities, religion or security, leading to strict acts of censorship and threats, which further instilled self-censorship in local and international news actors.This research found that most events of the Arab Spring were represented using footage in the event location, with minimal international representatives and with frames of peaceful demonstrations during the uprisings of Egypt, Syria and Yemen, and frames of violent riots in the Bahraini and Tunisian uprisings. Frames featuring destruction or explosions were observed in countries that experienced some kind of conflict, namely, Libya and Syria. Images of death and suffering were minimal and only evident in news representing the death of Gaddafi and the Ghoutta chemical attack. Majority of news interviews gave a voice to relevant event actors, as opposed to topic experts. The critical discourse analysis produced theories on the usage of various content in international news, namely: interviews, amateur content, figures and percentages, quotes and state TV content.