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A Novel Convolutional Neural Network Classification Approach of Motor-Imagery EEG Recording Based on Deep Learning
Get PDFAbstract: Recently, Electroencephalography (EEG) motor imagery (MI) signals have received increasing attention because it became possible to use these signals to encode a person’s intention to perform an action. Researchers have used MI signals to help people with partial or total paralysis, control devices such as exoskeletons, wheelchairs, prostheses, and even independent driving. Therefore, classifying the motor imagery tasks of these signals is important for a Brain-Computer Interface (BCI) system. Classifying the MI tasks from EEG signals is difficult to offer a good decoder due to the dynamic nature of the signal, its low signal-to-noise ratio, complexity, and dependence on the sensor positions. In this paper, we investigate five multilayer methods for classifying MI tasks: proposed methods based on Artificial Neural Network, Convolutional Neural Network 1 (CNN1), CNN2, CNN1 with CNN2 merged, and the modified CNN1 with CNN2 merged. These proposed methods use different spatial and temporal characteristics extracted from raw EEG data. We demonstrate that our proposed CNN1-based method outperforms state-of-the-art machine/deep learning techniques for EEG classification by an accuracy value of 68.77% and use spatial and frequency characteristics on the BCI Competition IV-2a dataset, which includes nine subjects performing four MI tasks (left/right hand, feet, and tongue). The experimental results demonstrate the feasibility of this proposed method for the classification of MI-EEG signals and can be applied successfully to BCI systems where the amount of data is large due to daily recording
The impact of Covid-19 on labour law protection for Uber drivers
Get PDFAbstract: On 15 March 2020 the President of the Republic of South Africa announced a nationwide lockdown. The unpredicted pandemic dictated that extraordinary measures be put in place, which resulted in the country coming to a total standstill. Consequently, there was an alarming decline in economic activities and therefore government had to introduce measures to mitigate the impact of COVID-19 on employers and workers...LL.M. (Commercial Law
Becoming African psychologists : decolonisation within a postgraduate psychology module at the University of Johannesburg
Get PDFAbstract: There is a compelling need for curriculum design and processes of teaching in South African higher education institutions to heed calls for decolonisation and relevance. Within university Psychology teaching spaces, both the what and the how of knowledge production require transformation and epistemic emancipation. This study explored the perceptions of students regarding the decolonisation processes within a postgraduate Psychology module at the University of Johannesburg. Through the thematic analyses of blogs written by students, results indicated the students benefitted from decolonisation initiatives through three interdependent processes. These processes were (1) Learning Real World Skills from Peers, (2) Bringing it Home: Making Psychology Relevant, and (3) Becoming African Psychologists. Academics in higher education institutions have an ontoepistemological responsibility to encourage students to be critical of the hegemony of Western imperialist forms of knowledge. Therefore, decolonisation initiatives should include students becoming agentic actors who chart the course of their learning processes. Critical thinking skills may facilitate the formation of identities that increase students’ agency and creativity within traditionally rigid and hierarchical academic structures
COVID-19: Leading in Disruptive Times – Challenges for School Leaders
Get PDFAbstract: Since South Africa went into lockdown as a result of the coronavirus disease 2019 (COVID-19) pandemic, school principals have been leading in chal-lenging circumstances. A combination of confusing government decisions and advice, compounded by a lack of decision-making by education districts, has resulted in many school principals having to make key decisions on a daily basis, many times being unsure of the support from departmental officials. Principals have had to ensure the continuation of the teaching and learning process even when the schools were closed, in some cases simultaneously developing a viable online systems in order to stay in contact with vulnerable learners and families. School leaders are uniquely positioned to guide families in supporting their children whilst at home during these unprecedented times. For school leaders, this becomes harder as schools serve families across vast geographic areas that may be without access to high-speed internet. How do school leaders lead educators and schools, which are doing their best to function effectively in uncharted territory, where teachers have had to move instruction online? Using a qualitative research approach, this study aimed to determine the challenges faced by school leaders in managing their schools during the early stages of the COVID-19 pandemic. Five schools in the Nelspruit area of Mpumalanga Province were selected through purposeful sampling. Data collected was categorised by themes and logically organised into workable units to facilitate coding. The findings revealed that COVID-19 has had an impact on principal leadership, challenging them to make decisions beyond their usual scope of management, relating to the feeding of learners, organi-sing personal protective equipment (PPE), finances and online learning plat-forms
Enhanced removal efficiency of heavy metal ions from wastewater through functionalized silicon carbide membrane : A theoretical study
Get PDFAbstract: Development and designing of heavy metal ion separation systems from wastewater play a essential role in environmental protection. For this purpose, in this research, we modeled the synthetic wastewater samples and investigated the capabilities of nano-porous silicon carbide membranes (SiC) with fluorine, nitrogen, and hydroxyl-atom decorated pores under hydrostatic pressures. Increase of applied pressure on SiC with larger pore diameters had more intense effects on water flux and ion rejection. It was also found that, due to different electronic properties of decorated atoms in the edge of pores, which played important roles in their interactions with water molecules and metal ions, as well as energy barrier and permeation, water flux and ion injection were improved. The potential of mean force (PMF) calculation showed that the energy barrier for passing through functionalized pores was higher for metal ions and lower for water molecules. The presence of functional groups in the edge of SiC pores provided selective ion rejection property which was highest for Zn2+ ions. PMF analysis results proved that the PMF values of metal ions were in the following comparative order: SiC@F>SiC@N>SiC@OH>SiC. It was also observed that increase in temperature significantly increased water flux and decreased ion rejection. Also, SiC membrane separation systems improved ion rejection in the presence of electric field along the opposite direction of piston movement, which was more intense in functionalized membranes and results indicated that in voltage of 200 mV/Å had the best ion rejection of about 98%
Consumer perception towards online shopping behaviour in South Africa
Get PDFAbstract: Customer perceptions affect their actions, leisure and buying habits, which has a great impact on online shopping. Globally, electronic retailing has undergone extraordinary growth in the past few years. In determining the uptake of online shopping behaviour in South Africa, the study set out to determine consumer perception towards online shopping. Through a quantitative approach, the study examines the perceptions of over 4 834 respondents who formed the sample for the study. The results reveal that prices and delivery time were the overall motivating factors to shop. The study also found that factors that influence respondents’ perception of online shopping were flexibility, convenience, and ease of accessibility. The study recommends dynamic pricing that applies variable pricing could be implemented more broadly, to online shoppers. Given the demographics of those who do not shop online, price discrimination using the third-degree discrimination strategy, which is based on the individual consumer, where, for example, students are given a reasonable price option, could potentially activate online shopping of those who do not engage in online shopping
New fossils of Australopithecus sediba reveal a nearly complete lower back
Get PDFAbstract: Adaptations of the lower back to bipedalism are frequently discussed but infrequently demonstrated in early fossil hominins. Newly discovered lumbar vertebrae contribute to a near-complete lower back of Malapa Hominin 2 (MH2), offering additional insights into posture and locomotion in Australopithecus sediba. We show that MH2 demonstrates a lower back consistent with human-like lumbar lordosis and other adaptations to bipedalism, including an increase in the width of intervertebral articular facets from the upper to lower lumbar column (“pyramidal configuration”). This contrasts with recent work on lordosis in fossil hominins, where MH2 was argued to demonstrate no appreciable lordosis (“hypolordosis”) similar to Neandertals. Our three-dimensional geometric morphometric (3D GM) analyses show that MH2’s nearly complete middle lumbar vertebra is human-like in shape but bears large, cranially-directed transverse processes, implying powerful trunk musculature. We interpret this combination of features to indicate that A. sediba used its lower back in both human-like bipedalism and ape-like arboreal positional behaviors, as previously suggested based on multiple lines of evidence from other parts of the skeleton and reconstructed paleobiology of A. sediba
Risk factors for tuberculosis in the 5 Northern districts of Botswana, 2018-2019
Get PDFAbstract: Background: Botswana, like many other countries remains at a challenging situation in terms of the fight against TB. Numerous studies have determined risk factors associated with TB, but the risk factors to acquiring TB localised to Botswana setting have not been explored. Objective: The aim of the study was to examine risk factors associated with acquiring TB in the 5 Northern districts of Botswana for the period of 2018-2019. Methods: This was a case-control study with sample size of 460 with 224 cases and 236 controls. The study was conducted in Botswana’s 5 northern districts. A questionnaire was administered to the participants by data collector. Convenience sampling was used for controls while TB registers were used to identify cases, and these were followed up for recruitment. Frequency distributions, cross tabulations, calculation of Odds Ratios were performed using EPINFO 7.2.4.0 while SPSS was used for logic Regression multivariate analysis adjusting for socio-demographic and lifestyle data.M.A. (Public Health
Attitudes and beliefs of South African chiropractors about managing back pain in Kwa-Zulu Natal : a cross sectional study
Get PDFAbstract: Background: Low back pain (LBP) is a prevalent musculoskeletal condition treated by health care practitioners, including chiropractors. Chiropractors make use of manual therapeutics to treat patients, often with a holistic approach. Currently, two primary schools of thought should be considered when treating LBP: biomedical and biopsychosocial. By determining which school of thought practitioners occupy, it is possible to better understand their LBP management approach. Aim: The primary aim of this study was to explore the attitudes and beliefs of chiropractors in Kwa-Zulu Natal, South Africa, regarding their preference of either a biomedical or biopsychosocial approach to LBP management. A secondary aim was to determine if any demographic variables affected the practitioners' preferred approaches to treatment. Method: This cross-sectional, exploratory study used the Pain Attitudes and Belief Scale for Physiotherapists (PABS-PT) to fulfil the research aims. The PABS-PT was created by Houben, Ostelo, Vlaeyen, Wolters, Peters, and Berg in 2005 for their study entitled "Health care providers' orientations towards common low back pain predict perceived harmfulness of physical activities and recommendations regarding return to regular activity". The PABS-PT was used to determine if practitioners occupied a biomedical or biopsychosocial approach to LBP. The survey had two subscales being biomedical and biopsychosocial...M.Tech. (Chiropractic
Microbiological analysis of the chiropractic clinic modality machines
Get PDFAbstract: OBJECTIVE The purpose of this study was to determine if the UJ Chiropractic Clinic modality machines and Chiropractic Intern’s personal clinic packs were a source of bacterial and fungal pathogens. As well as whether or not the Chiropractic Interns’ need to be taught a hygiene protocol which will be put into place to reduce transmission between patients in the clinic. METHODOLOGY Surface samples were collected from the UJ Chiropractic Clinic modality machines using sterile Hygiena Stick Sponges with neutralizing buffer. Samples were also collected from the electrode pads found in the Chiropractic Intern’s personal clinic packs by asking the students to place their electrode pads into sterile bags that were returned to them at their next clinic shift. All samples were taken as the objects were found, thereafter, they were disinfected with the Distel disinfection and a second sample was taken after a waiting period of 5 minutes. The samples from the modality machines were transported and stored under the appropriate conditions. They were then analysed using the spiral plater on Tryptic Soya Agar (TSA). These plates were then incubated overnight at 37°C. The following medias, Baird Parker Agar/Deoxycholate Citrate Agar/MacConkey Agar, were also used in the streak plate method. These plates were incubated overnight at 37°C. The samples from the Chiropractic Intern’s electrode pads were analysed by pressing them onto sterile agar for five seconds. The agar used was Plate Count Agar (PCA) and Deoxycholate Citrate Agar (DCA). They were analysed by the least selective to the most selective so that growth is not inhibited. The vii electrode pads were then sprayed with Distel Disinfectant, allowed to stand for five minutes and then re-inoculated with PCA first then DCA following the above process...M.Tech. (Chiropractic
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