55 research outputs found

    ABS braking on rough terrain

    Get PDF
    Anti-lock braking systems (ABS) have revolutionised vehicle safety by providing a mechanism for braking effectively whilst maintaining stability control. ABS works very well on smooth terrains, where there are little disturbances from the terrain and thus has been wildly adopted on commercial vehicles. The ability of ABS to perform on rough terrains is however deteriorated by the fact that rough terrains cause fluctuations in the wheel speeds and in the loading conditions of the tyre, which negatively affects the ABS algorithm as well as the tyre-terrain interaction. The adoption of ABS on off-road vehicles have been very slow due to these challenges. This study investigates the performance of ABS on rough terrain through performing experimental and simulated ABS tests using a testing trailer. A MSC ADAMS model of the trailer was built and validated. The ABS tests show good correlation between the tyre forces measured and the forces simulated using an FTire (Flexible Structure Tire Model) model in MSC ADAMS. The ABS algorithm’s performance deteriorates significantly due to the oscillation of wheel speeds. The work done in this study paves the way towards future ABS investigation and development using both the experimental and a simulated platform.Dissertation (MEng)--University of Pretoria, 2018.Mechanical and Aeronautical EngineeringMEngUnrestricte

    Crafting a Foucauldian Archaeology Method: A Critical Analysis of Occupational Therapy Curriculum-as-Discourse, South Africa

    Get PDF
    South Africa has a colonial and apartheid past of social injustice, epistemological oppression, and exclusion. These mechanisms are historically inscribed in the designs, practices, and content of higher education including in occupational therapy curriculum. If these historical markers are not consciously interrogated, patterns of reproduction are reified along the fault lines that already exist in society. The focus of this article is to demonstrate how an archaeological Foucauldian method was crafted from foundational Foucauldian archaeology analytics and existing approaches of Foucauldian discourse analysis to unearth the rules of the formation of the occupational therapy profession. These rules pertain to the formation of (a) the ideal occupational therapist (b) who had a say about the profession; (c) the ways of preferred reasoning; and (d) underlying theoretical themes and perspectives about the future. Data sources for this archaeology analytics included commemorative documents of universities on the origin of their programmes; historical regulatory documents; and the South African Journal of Occupational Therapy archive from the period 1953–1994. The analysis rendered two subthemes for each of the rules of formation including white exceptionalism, white male national, and international, regulatory bodies, the profession know-how practical knowledge, and its need for recognition within a bio-medical paradigm. Unearthing the historical markers of a curriculum and viewing it as discourse may enable a conscious reconfiguration thereof

    The effects of production system and sex on the sensory quality characteristics of dorperb lamb

    Get PDF
    The effect of production systems on the sensory quality characteristics of Dorper lambs was investigated. Sixty lambs (ewes, rams, castrates) were allocated into two production groups (feedlot or free-range) at weaning with equal numbers of each sex represented in each group. The lambs were fed for five (slaughter group 1) or six (slaughter group 2) weeks. Feedlot lambs were fed a commercial pelleted diet while free-range lambs utilized natural shrub pastures. Samples of the Longissimus thoracis muscle were used for sensory evaluation. Feedlot lambs produced meat that was juicier and more tender than meat from free-range lambs

    The South African guidelines on enuresis-2017

    Get PDF
    Introduction: Enuresis (or Nocturnal Enuresis) is defined as discreet episodes of urinary incontinence during sleep in children over 5 years of age in the absence of congenital or acquired neurological disorders. Recommendations: Suggestions and recommendations are made on the various therapeutic options available within a South African context. These therapeutic options include; behavioural modification, pharmaceutical therapy [Desmospressin (DDAVP), Anticholinergic (ACh) Agents, Mirabegron (beta 3-adrenoreceptor agonists), and Tricyclic Antidepressants (TCA)], alternative treatments, complementary therapies, urotherapy, alarm therapy, psychological therapy and biofeedback. The role of the Bladder Diary, additional investigations and Mobile Phone Applications (Apps) in enuresis is also explored. Standardised definitions are also outlined within this document. Conclusion: An independent, unbiased, national evaluation and treatment guideline based on the pathophysiological subcategory is proposed using an updated, evidence based approach. This Guideline has received endorsement from the South African Urological Association, Enuresis Academy of South Africa and further input from international experts within the field

    Ligand-Receptor Interactions

    Full text link
    The formation and dissociation of specific noncovalent interactions between a variety of macromolecules play a crucial role in the function of biological systems. During the last few years, three main lines of research led to a dramatic improvement of our understanding of these important phenomena. First, combination of genetic engineering and X ray cristallography made available a simultaneous knowledg of the precise structure and affinity of series or related ligand-receptor systems differing by a few well-defined atoms. Second, improvement of computer power and simulation techniques allowed extended exploration of the interaction of realistic macromolecules. Third, simultaneous development of a variety of techniques based on atomic force microscopy, hydrodynamic flow, biomembrane probes, optical tweezers, magnetic fields or flexible transducers yielded direct experimental information of the behavior of single ligand receptor bonds. At the same time, investigation of well defined cellular models raised the interest of biologists to the kinetic and mechanical properties of cell membrane receptors. The aim of this review is to give a description of these advances that benefitted from a largely multidisciplinar approach

    ENIGMA and global neuroscience: A decade of large-scale studies of the brain in health and disease across more than 40 countries

    Get PDF
    This review summarizes the last decade of work by the ENIGMA (Enhancing NeuroImaging Genetics through Meta Analysis) Consortium, a global alliance of over 1400 scientists across 43 countries, studying the human brain in health and disease. Building on large-scale genetic studies that discovered the first robustly replicated genetic loci associated with brain metrics, ENIGMA has diversified into over 50 working groups (WGs), pooling worldwide data and expertise to answer fundamental questions in neuroscience, psychiatry, neurology, and genetics. Most ENIGMA WGs focus on specific psychiatric and neurological conditions, other WGs study normal variation due to sex and gender differences, or development and aging; still other WGs develop methodological pipelines and tools to facilitate harmonized analyses of "big data" (i.e., genetic and epigenetic data, multimodal MRI, and electroencephalography data). These international efforts have yielded the largest neuroimaging studies to date in schizophrenia, bipolar disorder, major depressive disorder, post-traumatic stress disorder, substance use disorders, obsessive-compulsive disorder, attention-deficit/hyperactivity disorder, autism spectrum disorders, epilepsy, and 22q11.2 deletion syndrome. More recent ENIGMA WGs have formed to study anxiety disorders, suicidal thoughts and behavior, sleep and insomnia, eating disorders, irritability, brain injury, antisocial personality and conduct disorder, and dissociative identity disorder. Here, we summarize the first decade of ENIGMA's activities and ongoing projects, and describe the successes and challenges encountered along the way. We highlight the advantages of collaborative large-scale coordinated data analyses for testing reproducibility and robustness of findings, offering the opportunity to identify brain systems involved in clinical syndromes across diverse samples and associated genetic, environmental, demographic, cognitive, and psychosocial factors

    Review about mites (Acari) of rubber trees (Hevea spp., Euphorbiaceae) in Brazil

    Full text link
    • …
    corecore