WIReDSpace

Welcome to WIReDSpace(Wits Institutional Repository on DSpace)

For queries relating to content and technical issues, please contact IR specialists via this email address : openscholarship.library@wits.ac.za, Tel: 011 717 4652 or 011 717 1954

 

Communities in WIReDSpace

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Now showing 1 - 5 of 19

Recent Submissions

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The application of weakly supervised learning in the search for heavy resonances at the LHC
(University of the Witwatersrand, Johannesburg, 2023-06) Choma, Nalamotse Joshua; Ruan, Xifeng; Mellado, Bruce
The discovery of the Higgs boson at the Large Hadron Collider by the ATLAS and CMS experiments has made the search for new physics beyond the Standard Model a priority in the field of High Energy Particle Physics. New resonances have yet to be discovered using inclusive and model-dependent searches, which means they may be driven by subtle topologies. Rapid improvements in Machine Learning techniques have led to their increasing application in High Energy Particle physics. Unlike supervised learning, which is known to assume full knowledge of the underlying model, semi-supervised learning, in particular weakly supervised learning, allows the extraction of new information from data with partial knowledge. The goal of this study is to set up searches for heavy resonances at the electroweak scale with topological requirements performed in both inclusive and exclusive regions of phase-space tailored to a particular production mode. These resonances could be generated with different production mechanisms. In this work, we describe search procedures based on weakly supervised learning applied to mixed samples and used to search for resonances with little or no prior knowledge of the production mechanism. This approach has the advantage that sidebands or control regions can be used to effectively model backgrounds without relying on models. The effectiveness of this method is measured by the production of the Standard Model Higgs boson, which decays into a pair of photons in both inclusive and exclusive regions of phase-space at the LHC. Having confirmed the ability of the method to extract various Standard Model Higgs boson signal processes, the search for new phenomena in high mass final states will be set up at the LHC. Subsequently, the approach is used in the search for new resonances in the Zγ final state with Z → e +e − or Z → µ +µ −, using the Monte Carlo simulated signal samples for 139 fb−1 of integrated luminosity for Run 2 collected at the LHC. The weakly supervised learning approach is implemented and compared to the performance of the fully supervised approach, which is then used to calculate the production limit for Higgs-like particles for Zγ where the significance of the signal is maximal.
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Teacher pedagogies for literacy acquisition amongst EFAL learners in Grade 3 in two schools in the Western Cape
(University of the Witwatersrand, Johannesburg, 2023-08) Dooms, Anastasia Chloe; Martin, Cameron
The issue of literacy and language development is still a pressing concern within South African education. Many South African learners that are required to attend school and learn in their first/second additional language (FAL) as opposed to their home language (HL) are disadvantaged and comparatively excluded compared to their peers that learn in their HL. In the foundation phase, literacy acquisition is seen as a building block to education and therefore teachers need to ensure that learners have acquired adequate oral vocabulary and phonological awareness in English to enable a strong literacy foundation for their transition from their HL to English (EFAL). This study analysed the pedagogical practices used by four Grade 3 educators from two non-English schools in the Western Cape during their EFAL lessons. The research intended to identify the pedagogical approaches used by these educators to assist learners in learning and adequately acquiring their FAL to the level of proficiency needed for English as the language of instruction from Grade 4 onwards. A qualitative approach was used and incorporated the use of two EFAL lesson observations (per educator), lesson plan analyses, and semi-structured interviews. The main findings were analysed through the lens of Pedagogical Link-Making (PLM) (Scott et al., 2011). PLM as an evaluation tool was used to guide and thereafter analyse the observations and the post-observation interviews. This was used to establish the effective pedagogies used by Grade 3 educators to establish meaning amongst their learners. The findings gave insight into promising pedagogical actions that should be incorporated into teaching and learning EFAL to facilitate meaning making amongst learners and ensure adequate language and literacy acquisition. The inclusive education field will benefit from further research being conducted into PLM, with particular interest in language and literacy development. This may aid the field of education to find new ways for educators to adapt their pedagogical practices to foster inclusion within their classroom and hinder the exclusionary practices faced by EFAL learners due to learning barriers imposed by language.
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The Effects of Mathematical Modelling and its Application in Algebraic Functions on Grade 11 Learners’ Performance
(University of the Witwatersrand, Johannesburg, 2023-07) Ngubane, Sibongiseni; Ekol, George
To explore the effects of mathematical modelling on Grade 11 learners’ academic performance in algebraic functions, teachers’ self-efficacy and their overall perceptions, is the purpose of this research study. For the achievement of this goal, the research study followed a mixed method for both collecting and analyzing data. However, a pre-test and a post-test, interviews, and a questionnaire were used to collect data. The study content was limited to mathematical modelling in algebraic functions, learners doing pure mathematics in Grade 11, and mathematics teachers in the FET phase only. Eighty-seven (87) Grade 11 learners doing mathematics from one (1) selected school under the ILembe district in KwaZulu Natal participated in the research study, where 44 (51%) formed an experimental group and the other 43 (49%) learners formed a control group. Findings revealed that the experimental group taught through modelling with a guided discovery approach outperformed the control group that was taught through a direct instruction approach to learning. Hence, the difference between the modelling and direct instruction teaching approaches is statistically significant. Six (6) learners from the experimental group were purposively sampled to participate in the semi-structured interviews for the researcher's purposes of exploring learners’ perceptions about mathematical modelling. Learners reported that modelling could improve their level of cognition. Thirty-three (33) mathematics teachers in the FET phase from fourteen (14) high schools in KwaZulu Natal participated in the study by completing a questionnaire about modelling. Findings revealed that teachers have positive attitudes, beliefs, and perceptions about modelling in mathematics education even though there are no teachers’ professional development workshops provided to encourage them based on modelling. This study recommended that the department of education put more efforts into supporting and motivating teachers to implement modelling in mathematics classrooms, provide teachers with professional development workshops based on modelling, design and distribute teaching and learning support documents to all schools providing mathematics, and do follow-up to check the progress in teachers’ developments.
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The role of TPACK in enhancing students' knowledge of the design process: A case study of Grade 9 Technology Educators
(University of the Witwatersrand, Johannesburg, 2023-07) Modise, Refilwe; Dewa, Alton
The department of basic education is making efforts to transform educator pedagogy by introducing the use of digital technology in South African classrooms. Thus, the utilisation of digital tools in the technology classroom is likely to improve the students‟ comprehension of the design process. Educators need a well-developed Technological pedagogical content knowledge to meaningfully integrate Technology in their classrooms. The core purpose of this research is to investigate the role of the TPACK body of knowledge in enhancing grade 9 student understanding of the design process to improve learner achievement and to allow learners to design models that are fit-for-purpose and usable beyond the classroom. This is a qualitative research study aimed at capturing rich-data to answer the main research questions of the study. The TPACK framework was used in this study to determine the role of TPACK in enhancing the knowledge of students when they learn the design process. The data collection method used was interviews, where five grade 9 educators were purposively sampled from Sedibeng east to establish the role of TPACK in the Technology classroom. The study is underpinned by constructivism and social constructivism learning theory that follows a learner centred approach to teaching the design process. The finding of the study reveal that educators are interested in using digital tools in their classroom, however they are constrained by the lack of technological support, limited access to digital tools and the lack of Technological pedagogical content knowledge. The findings further reveal that educators are attempting the integration of technology in the classroom but they do not appropriately articulate the affordances of digital tools that will enhance the learners understanding of the design process. To answer the research question, the role TPACK cannot be meaningfully measured as the educators showed a lack of Technological pedagogical content knowledge. According to the educators‟ point of view, students became interested in the lesson when they used digital tools therefore, if they can be trained in using digital tools, they will be able to enhance the understanding of students in the design process. This would allow learners to design and make models that fit-for-purpose and come up with solutions that show a deeper understanding of the problem they had to investigate. The finding further shows that if the TPACK can be used meaningfully, it will play an important role in learning of the design process. In future Pre-service and in-service educators must be equipped with TPACK body of knowledge and more digital tools must be available in the Technology classroom for the learners to meet the learning outcomes of the design process.
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Grade 10 Learners errors when operating Integers
(University of the Witwatersrand, Johannesburg, 2023-10) Naidoo, Sheldon Samuel; Pournara, Craig
This study focuses on learners’ errors in integers and explores the changes in their errors during their grade 10 year. The data utilised in this study was collected by the WMCS project in 2018. The data was collected from learners of 15 low-performing schools in Gauteng, South Africa. Part of this study consisted of a comparison of two groups of learner responses. The first group comprised of learners of teachers who participated in a professional development course offered by the project in 2016/2017 (TM group) and the second group are learners whose teachers did not attend the course (CNT group). These schools had no prior relationships with the Wits Maths Connect Secondary (WMCS) project. I looked at the responses that grade10 learners made when ordering and operating on integers at two different points of a school year. The tests were written in February and September of the same year and were analysed from a random sample of 196 grade 10 learners from 40 low-performing secondary schools in Gauteng, South Africa. Test items dealt with ordering of integers and operating on integers. Working from a Vygotskian perspective, a framework dealing with concept formation of negative numbers was developed to analyse learners’ test responses. In this study, I focused solely on the responses given by the learners of the two groups and explored the persistency of errors within each group as well as the type of errors found across the groups. Having this data point per learner allowed for further investigations regarding persistent errors and errors which were remediated and waned during the year. Furthermore, it provided an opportunity to detect new errors arising which would impact the learning of other topics. This framework made it possible to identify seven types of errors. The findings show that while learners’ performance improved from pre-test to post-test, many grade 10 leaners still have difficulty with the concept of negative numbers.