Search results for: Khashane Stephen Malatji
225 Exploring Students’ Voices in Lecturers’ Teaching and Learning Developmental Trajectory
Authors: Khashane Stephen Malatji, Makwalete Johanna Malatji
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Student evaluation of teaching (SET) is the common way of assessing teaching quality at universities and tracing the professional growth of lecturers. The aim of this study was to investigate the role played by student evaluation in the teaching and learning agenda at one South African University. The researchers used a qualitative approach and a case study research design. With regards to data collection, document analysis was used. Evaluation reports were reviewed to monitor the growth of lecturers who were evaluated during the academic years 2020 and 2021 in one faculty. The results of the study reveal that student evaluation remains the most relevant tool to inform the teaching agenda at a university. Lecturers who were evaluated were found to grow academically. All lecturers evaluated during 2020 have shown great improvement when evaluated repeatedly during 2021. Therefore, it can be concluded that student evaluation helps to improve the pedagogical and professional proficiency of lecturers. The study therefore, recommends that lecturers conduct an evaluation for each module they teach every semester or annually in case of year modules. The study also recommends that lecturers attend to all areas that draw negative comments from students in order to improve.Keywords: students’ voices, teaching agenda, evaluation, feedback, responses
Procedia PDF Downloads 89224 Design of a Controlled BHJ Solar Cell Using Modified Organic Vapor Spray Deposition Technique
Authors: F. Stephen Joe, V. Sathya Narayanan, V. R. Sanal Kumar
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A comprehensive review of the literature on photovoltaic cells has been carried out for exploring the better options for cost efficient technologies for future solar cell applications. Literature review reveals that the Bulk Heterojunction (BHJ) Polymer Solar cells offer special opportunities as renewable energy resources. It is evident from the previous studies that the device fabricated with TiOx layer shows better power conversion efficiency than that of the device without TiOx layer. In this paper, authors designed a controlled BHJ solar cell using a modified organic vapor spray deposition technique facilitated with a vertical-moving gun named as 'Stephen Joe Technique' for getting a desirable surface pattern over the substrate to improving its efficiency over the years for industrial applications. We comprehended that the efficient processing and the interface engineering of these solar cells could increase the efficiency up to 5-10 %.Keywords: BHJ polymer solar cell, photovoltaic cell, solar cell, Stephen Joe technique
Procedia PDF Downloads 543223 Investigation of Microstructure, Mechanical Properties and Anti-Corrosive Behavior of Al2O3/Cr2O3 Nanocomposite on Zn Rich Bath
Authors: N. Malatji, A. P. I. Popoola
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Zn-Al2O3 and Cr2O3 nanocomposite coatings were successfully produced by electrodeposition technique from chloride acidic bath. Particle loading of Al2O3 (50nm) particles were varied from 5-10 g/L and for Cr2O3(100nm) was 10-20 g/L. Scanning electron microscope (SEM) affixed with energy dispersive spectrometry was used to study the surface morphology and content of the nanoparticles incorporated into the coatings. Microhardness, thermal stability, wear and corrosion behavior of the coatings were also evaluated to study the effect of these nanoparticles on these properties. Zn-Al2O3 nanocomposite was found to exhibit good surface properties especially corrosion resistance. On the other side, Cr2O3 incorporation resulted in the improvement of only mechanical properties. Therefore, Zn-Al2O3 proved to be a better coating for most industrial applications where both chemical and mechanical properties are required.Keywords: electrodeposition, nanocomposite coatings, corrosion, thermal stability, tribology
Procedia PDF Downloads 389222 Influence of Sintering Temperature on Microhardness and Tribological Properties of Equi-Atomic Ti-Al-Mo-Si-W Multicomponent Alloy
Authors: Rudolf L. Kanyane, Nicolaus Malatji, Patritia A. Popoola
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Tribological failure of materials during application can lead to catastrophic events which also carry economic penalties. High entropy alloys (HEAs) have shown outstanding tribological properties in applications such as mechanical parts were moving parts under high friction are required. This work aims to investigate the effect of sintering temperature on microhardness properties and tribological properties of novel equiatomic TiAlMoSiW HEAs fabricated via spark plasma sintering. The effect of Spark plasma sintering temperature on morphological evolution and phase formation was also investigated. The microstructure and the phases formed for the developed HEAs were examined using scanning electron microscopy (SEM) and X-ray diffractometry (XRD) respectively. The microhardness and tribological properties were studied using a diamond base microhardness tester Rtec tribometer. The developed HEAs showed improved mechanical properties as the sintering temperature increases.Keywords: sintering, high entropy alloy, microhardness, tribology
Procedia PDF Downloads 134221 Mitigation Measures for the Acid Mine Drainage Emanating from the Sabie Goldfield: Case Study of the Nestor Mine
Authors: Rudzani Lusunzi, Frans Waanders, Elvis Fosso-Kankeu, Robert Khashane Netshitungulwana
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The Sabie Goldfield has a history of gold mining dating back more than a century. Acid mine drainage (AMD) from the Nestor mine tailings storage facility (MTSF) poses a serious threat to the nearby ecosystem, specifically the Sabie River system. This study aims at developing mitigation measures for the AMD emanating from the Nestor MTSF using materials from the Glynns Lydenburg MTSF. The Nestor MTSF (NM) and the Glynns Lydenburg MTSF (GM) each provided about 20 kg of bulk composite samples. Using samples from the Nestor MTSF and the Glynns Lydenburg MTSF, two mixtures were created. MIX-A is a mixture that contains 25% weight percent (GM) and 75% weight percent (NM). MIX-B is the name given to the second mixture, which contains 50% AN and 50% AG. The same static test, i.e., acid–base accounting (ABA), net acid generation (NAG), and acid buffering characteristics curve (ABCC) was used to estimate the acid-generating probabilities of samples NM and GM for MIX-A and MIX-B. Furthermore, the mineralogy of the Nestor MTSF samples consists of the primary acid-producing mineral pyrite as well as the secondary minerals ferricopiapite and jarosite, which are common in acidic conditions. The Glynns Lydenburg MTSF samples, on the other hand, contain primary acid-neutralizing minerals calcite and dolomite. Based on the assessment conducted, materials from the Glynns Lydenburg are capable of neutralizing AMD from Nestor MTSF. Therefore, the alkaline tailings materials from the Glynns Lydenburg MTSF can be used to rehabilitate the acidic Nestor MTSF.Keywords: Nestor Mine, acid mine drainage, mitigation, Sabie River system
Procedia PDF Downloads 85220 The Effects of Fungicide and Genetics on Fungal Diseases on Wheat in Nebraska With Emphasis on Stem Rust
Authors: Javed Sidiqi, Stephen Baezinger, Stephen Wegulo
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Wheat (Triticum aestivum L.) production continues to be challenged by foliar fungal diseases although significant improvement has been made to manage the diseases through developing resistant varieties and the fungicide use to ensure sufficient wheat is produced to meet the growing population’s need. Significant crop losses have been recorded in the history of grain production and yield losses due to fungal diseases, and the trend continues to threat food security in the world and particularly in the less developed countries. The impact of individual fungal diseases on grain yield has been studied extensively to determine crop losses. However, there is limited research available to find out the combined effects of fungal diseases on grain yield and the ways to effectively manage the diseases. Therefore, the objectives of this research were to study the effect of fungal pathogens on grain yield of pre-released winter wheat genotypes in fungicide treated and untreated plots, and to determine whether S7b gene was present in ‘Gage’ wheat as previously hypothesized. Sixty winter wheat genotypes in fungicide treated and untreated plots were studied across four environments. There was a significant effect of fungicide on grain yield consistently across four environments in three years. Fungicide treated wheat lines demonstrated (4,496 kg/ ha-1) grain yield compared to (3,147 kg/ ha-1) grain yield in untreated wheat lines indicating 43% increased grain yield due to severity of foliar fungal diseases. Furthermore, fungicide application also caused an increase in protein concentration from 153 (g kg-1) to 164 (g kg-1) in treated plots in along with test weight from 73 to 77 (kg hL-1) respectively. Gage wheat variety and ISr7b-Ra were crossed to determine presence of Sr7b in Gage. The F2 and F2:3 segregating families were screened and evaluated for stem rust resistance. The segregation of families fell within 15:1 ratio for two separate resistance genes suggesting that Sr7b segregates independently from an unknown resistance gene in Gage that needs to be characterized for its use in the future wheat breeding program to develop resistant wheat varieties.Keywords: funicide, genetics, foliar diseases, grain
Procedia PDF Downloads 126219 The Effects of Absenteeism on Nurses That Remain at Work at the Mankweng Hospital in the Capricorn District, Limpopo Province in South Africa
Authors: Mokgadi Malatji, Tebogo Mothiba, Rambelani Malema
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Absenteeism is a global problem in the working force and this is no exception in the nursing profession. A lot of attention has been drawn to factors that contribute to absenteeism however little attention has been placed on the effects of absenteeism on the remaining workers/nurses being left behind in the workplace by their colleagues. Nurses absent themselves leaving behind their colleagues to do their work. Nurses who are committed to their work often find themselves working under strenuous conditions due to inadequate staff. These may lead to poor patient care provision, nurses feeling overworked and sick due to the increased workload. The purpose of this study was to investigate the effects of absenteeism on nurses that remained at work at Mankweng Hospital in the Capricorn District, Limpopo Province. A descriptive cross-sectional quantitative research design was conducted to determine if there were any effects of absenteeism on nurses remaining at work. Data collection was done using structured questionnaires. The respondents (n=107), consisted of different categories of registered nurses (professional nurses (n=43), auxiliary nurses (n=40) and staff nurses (n=24)) who participated in this study. The findings indicated that most nurses (76, 6%) are demotivated and they struggle with completion of duties when their colleagues are absent. Patient care that nurses provided when their colleagues were absent was of poor quality as set standards and principles were not adhered to. Individualized patient care was not being implemented due to absenteeism. This simply implies that routine work is being done to cover basic duties. Most nurses (74, 8%) believed that favoritism and lack of appreciation of nurse’s skills and capabilities are being displayed by managers and that this contributes to absenteeism. Nurses who are loyal sacrifice their time and work overtime for absent colleagues and this led to fatigue and stress. From the study findings, it is recommended that nurses be trained frequently to upgrade their studies to motivate them to work. The government can provide this training to improve their skills as this will motivate nurses to work harder and be committed to their work. Training can be offered after a stipulated period. For example, after every five years, a nurse can be provided with a new skill. Team building events must be encouraged for the whole hospital to motivate staff. In conclusion, the study revealed that absenteeism poses detrimental effects on nurses, the hospital and patients. More and more nurses end up changing workplace due to these effects.Keywords: absenteeism, effects, nurses, remaining at work
Procedia PDF Downloads 254218 Complimentary Allusions: Shawl Scenes in Rossellini, Lean, Fellini, Kubrick, and Bertolucci Films
Authors: Misha Nedeljkovich
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In the film’s famous scene (Roma città aperta-1945), Pina (Anna Magnani) collapses in the street when machined-gunned by a German soldier. Her son Marcello (Vito Annchiarico) tries to revive her. Her death is signaling not closure, but the cycle of life; Marcello saves Francesco with the shawl taken from his mother’s corpse. One pivotal scene in Brief Encounter (1945) occurs in the apartment of Alec’s (Trevor Howard) friend Stephen (Valentine Dyall), when Stephen returns to catch Alec and Laura (Celia Johnson) together alone. David Lean directs this scene using her shawl as a sign of in flagrante delicto. In La Strada (1954), Gelsomina (Giulietta Masina) was waving good bye when her mother sensing impending doom changed her mind and desperately tried to stop her waving back with her shawl: Don’t go my daughter! Your shawl! Your shawl! Gelsomina refuses to return, waving back: It’s time to go! Stanley Kubrick’s tale of a boxer who crosses a mobster to win the heart of a lady, Killer’s Kiss (1955), reminds us that Times Square used to contain sweaty boxing gyms and dance halls. The film’s longest Times Square interlude is its oddest: the boxer Davie Gordon played by Jamie Smith has his shawl stolen by two playful men in Shriners’ hats who are silent except for one who blows a harmonica, faintly heard over honking cabs and overheard conversations. This long sequence appears to be joining in on directors’ shawl conversations with Kubrick’s own twist. Principle characters will never know why all this happened to them that evening. Love, death, happiness and everlasting misery all of that is caused by Dave’s shawl. Finally, the decade of cinematic shawl conversations conclude in Betolucci’s Before the Revolution (Prima della rivoluzione–1964). One of his character’s lifts up a shawl asking if this was a Rossellini’s shawl. I argue that exploring complimentary allusions in a film where directors are acknowledging their own great debt to another film or filmmaker will further our knowledge of film history adding both depth and resonance to the great works in cinema.Keywords: allusions, Bertolucci, Fellini, homage, Kubrick, lean, Rossellini
Procedia PDF Downloads 395217 WebGIS Development Framework With Prioritized Usability Elements
Authors: Ezekiel Mwangi, Stephen Kimani, Agnes Mindila
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Usability is one of the key factors that determine the success or failure of any WebGIS (technology normally applied on the internet to analyze and present spatial data on the Internet). However, not all the usability attributes have the same impact on usability. It is, therefore, necessary to prioritize WebGIS usability elements and determine the ones that are more crucial to the success of the WebGIS. This research aims to identify the main elements of WebGIS usability, investigate the order of importance and priority of the usability elements of WebGIS, and propose a WebGIS development framework that incorporates the prioritization of the usability elements. This will be achieved through a literature review. The outcome of this research will help usability specialists and WebGIS developers in determining specific usability elements that should be accorded more emphasis during the design and development of WebGIS.Keywords: framework, prioritization, usability, WebGIS
Procedia PDF Downloads 158216 Increased Circularity in Metals Production Using the Ausmelt TSL Process
Authors: Jacob Wood, David Wilson, Stephen Hughes
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The Ausmelt Top Submerged Lance (TSL) Process has been widely applied for the processing of both primary and secondary copper, nickel, lead, tin, and zinc-bearing feed materials. Continual development and evolution of the technology over more than 30 years has resulted in a more intense smelting process with higher energy efficiency, improved metal recoveries, lower operating costs, and reduced fossil fuel consumption. This paper covers a number of recent advances to the technology, highlighting their positive impacts on smelter operating costs, environmental performance, and contribution towards increased circularity in metals production.Keywords: ausmelt TSL, smelting, circular economy, energy efficiency
Procedia PDF Downloads 244215 Sequential Data Assimilation with High-Frequency (HF) Radar Surface Current
Authors: Lei Ren, Michael Hartnett, Stephen Nash
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The abundant measured surface current from HF radar system in coastal area is assimilated into model to improve the modeling forecasting ability. A simple sequential data assimilation scheme, Direct Insertion (DI), is applied to update model forecast states. The influence of Direct Insertion data assimilation over time is analyzed at one reference point. Vector maps of surface current from models are compared with HF radar measurements. Root-Mean-Squared-Error (RMSE) between modeling results and HF radar measurements is calculated during the last four days with no data assimilation.Keywords: data assimilation, CODAR, HF radar, surface current, direct insertion
Procedia PDF Downloads 573214 Carbon Nanotubes Synthesized Using Sugar Cane as a Percursor
Authors: Vanessa Romanovicz, Beatriz A. Berns, Stephen D. Carpenter, Deyse Carpenter
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This article deals with the carbon nanotubes (CNT) synthesized from a novel precursor, sugar cane and Anodic Aluminum Oxide (AAO). The objective was to produce CNTs to be used as catalyst supports for Proton Exchange Membranes. The influence of temperature, inert gas flow rate and concentration of the precursor is presented. The CNTs prepared were characterized using TEM, XRD, Raman Spectroscopy, and the surface area determined by BET. The results show that it is possible to form CNT from sugar cane by pyrolysis and the CNTs are the type multi-walled carbon nanotubes. The MWCNTs are short and closed at the two ends with very small surface area of SBET = 3.691m,/g.Keywords: carbon nanotubes, sugar cane, fuel cell, catalyst support
Procedia PDF Downloads 446213 Microwave Production of Geopolymers Using Fluidized Bed Combustion Bottom Ash
Authors: Osholana Tobi Stephen, Rotimi Emmanuel Sadiku, Bilainu Oboirien.o
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Fluidized bed combustion (FBC) is a clean coal technology used in the combustion of low-grade coals for power generation. The production of large solid wastes such as bottom ashes from this process is a problem. The bottom ash contains some toxic elements which can leach out soils and contaminate surface and ground water; for this reason, they can neither be disposed in landfills nor lagoons anymore. The production of geopolymers from bottom ash for structural and concrete applications is an option for their disposal. In this study, the waste bottom ash obtained from the combustion of three low grade South African coals in a bubbling fluidized bed reactor was used to produce geopolymers. The geopolymers were cured in a household microwave. The results showed that the microwave curing enhanced the reactivity and strength of the geopolymers.Keywords: bottom ash, coal, fluidized bed combustion (FBC) geopolymer, compressive strength
Procedia PDF Downloads 315212 The Learning Impact of a 4-Dimensional Digital Construction Learning Environment
Authors: Chris Landorf, Stephen Ward
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This paper addresses a virtual environment approach to work integrated learning for students in construction-related disciplines. The virtual approach provides a safe and pedagogically rigorous environment where students can apply theoretical knowledge in a simulated real-world context. The paper describes the development of a 4-dimensional digital construction environment and associated learning activities funded by the Australian Office for Learning and Teaching. The environment was trialled with over 1,300 students and evaluated through questionnaires, observational studies and coursework analysis. Results demonstrate a positive impact on students’ technical learning and collaboration skills, but there is need for further research in relation to critical thinking skills and work-readiness.Keywords: architectural education, construction industry, digital learning environments, immersive learning
Procedia PDF Downloads 410211 Information and Communication Technology in Architectural Education: The Challenges
Authors: Oluropo Stephen Ilesanmi, Oluwole Ayodele Alejo
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Architectural education, beyond training the students to become architects, impacts in them the appreciation of the responsibilities relating to public health, safety, and welfare. Architecture is no longer a personal philosophical or aesthetic pursuit by individuals, rather, it has to consider everyday needs of the people and use technology to give a liveable environment. In the present age, architectural education must have to grapple with the recent integration of technology, in particular, facilities offered by information and communication technology. Electronic technologies have moved architecture from the drawing board to cyberspace. The world is now a global village in which new information and methods are easily and quickly available to people at different poles of the globe. It is the position of this paper that in order to remain relevant in the ever-competing forces within the building industry, architectural education must show the impetus to continue to draw from technological advancements associated with the use of computers.Keywords: architecture, education, communication, information, technology
Procedia PDF Downloads 209210 Laundering vs. Blanqueo: Translating Financial Crime Metaphors From English to Spanish
Authors: Stephen Gerome
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This study examines the translation and use of metaphors in the realm of public safety discourse and intends to shed light on a continuing problem in cross-cultural communication. Metaphors can cause problems not only within languages but also in interlingual communication. The use and misuse of metaphors may hinder the ability to adequately communicate prevention efforts and, in some cases, facilitate and allow financial crime to go undetected. The use of lexicalized metaphors in communications by political entities, journalists, and legal agents in communications regarding law, policy making, compliance monitoring and enforcement as well as in adjudication can have negative consequences if misconstrued. This study provides examples of metaphor usage in published documents in a corpus linguistic study that compares the use of lexicalized metaphors in this discourse to shed light on possible unexpected consequences as well as counterproductive ones.Keywords: translation, legal, corpus linguistics, financial
Procedia PDF Downloads 119209 A Paradigm Shift in Energy Policy and Use: Exergy and Hybrid Renewable Energy Technologies
Authors: Adavbiele Airewe Stephen
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Sustainable energy use is exploiting energy resources within acceptable levels of global resource depletion without destroying the ecological balance of an area. In the context of sustainability, the rush to quell the energy crisis of the fossil fuels of the 1970's by embarking on nuclear energy technology has now been seen as a disaster. In the circumstance, action (policy) suggested in this study to avoid future occurrence is exergy maximization/entropy generation minimization and the use is renewable energy technologies that are hybrid based. Thirty-two (32) selected hybrid renewable energy technologies were assessed with respect to their energetic efficiencies and entropy generation. The results indicated that determining which of the hybrid technologies is the most efficient process and sustainable is a matter of defining efficiency and knowing which of them possesses the minimum entropy generation.Keywords: entropy, exergy, hybrid renewable energy technologies, sustainability
Procedia PDF Downloads 445208 An Example of University Research Driving University-Industry Collaboration
Authors: Stephen E. Cross, Donald P. McConnell
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In the past decade, market pressures and decreasing U.S. federal budgets for science and technology have led to a fundamental change in expectations for corporate investments in innovation. The trend to significant, sustained corporate research collaboration with major academic centres has called for rethinking the balance between academic and corporate roles in these relationships. The Georgia Institute of Technology has developed a system-focused strategy for transformational research focused on grand challenges in areas of importance both to faculty and to industry collaborators. A model of an innovation ecosystem is used to guide both research and university-industry collaboration. The paper describes the strategy, the model, and the results to date including the benefits both to university research and industry collaboration. Key lessons learned are presented based on this experience.Keywords: ecosystem, industry collaboration, innovation, research strategy
Procedia PDF Downloads 420207 Overcoming the Problems Affecting Drip Irrigation System through the Design of an Efficient Filtration and Flushing System
Authors: Stephen A. Akinlabi, Esther T. Akinlabi
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The drip irrigation system is one of the important areas that affect the livelihood of farmers directly. The use of drip irrigation system has been the most efficient system compared to the other types of irrigations systems because the drip irrigation helps to save water and increase the productivity of crops. But like any other system, it can be considered inefficient when the filters and the emitters get clogged while in operation. The efficiency of the entire system is reduced when the emitters are clogged and blocked. This consequently impact and affect the farm operations which may result in scarcity of farm products and increase the demand. This design work focuses on how to overcome some of the challenges affecting drip irrigation system through the design of an efficient filtration and flushing system.Keywords: drip irrigation system, filters, soil texture, mechanical engineering design, analysis
Procedia PDF Downloads 383206 An Overview of Nano-Particles Effect on Mechanical Properties of Composites
Authors: Ganiyu I. Lawal, Olatunde I. Sekunowo, Stephen I. Durowaye
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Composites depending on the nature of their constituents and mode of production are regarded as one of the advanced materials that drive today’s technology. This paper attempts a short review of the subject matter with a general aim of pushing to the next level the frontier of knowledge as it impacts the technology of nano-particles manufacturing. The objectives entail an effort to; aggregate recent research efforts in this field, analyse research findings and observations, streamline research efforts and support industry in taking decision on areas of fund deployment. It is envisaged that this work will serve as a quick hand-on compendium material for researchers in this field and a guide to relevant government departments wishing to fund a research whose outcomes have the potential of improving the nation’s GDP.Keywords: advanced materials, composites, mechanical properties, nano-particles
Procedia PDF Downloads 276205 The Boundary Element Method in Excel for Teaching Vector Calculus and Simulation
Authors: Stephen Kirkup
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This paper discusses the implementation of the boundary element method (BEM) on an Excel spreadsheet and how it can be used in teaching vector calculus and simulation. There are two separate spreadheets, within which Laplace equation is solved by the BEM in two dimensions (LIBEM2) and axisymmetric three dimensions (LBEMA). The main algorithms are implemented in the associated programming language within Excel, Visual Basic for Applications (VBA). The BEM only requires a boundary mesh and hence it is a relatively accessible method. The BEM in the open spreadsheet environment is demonstrated as being useful as an aid to teaching and learning. The application of the BEM implemented on a spreadsheet for educational purposes in introductory vector calculus and simulation is explored. The development of assignment work is discussed, and sample results from student work are given. The spreadsheets were found to be useful tools in developing the students’ understanding of vector calculus and in simulating heat conduction.Keywords: boundary element method, Laplace’s equation, vector calculus, simulation, education
Procedia PDF Downloads 163204 Towards a Competitive South African Tooling Industry
Authors: Mncedisi Trinity Dewa, Andre Francois Van Der Merwe, Stephen Matope
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Tool, Die and Mould-making (TDM) firms have been known to play a pivotal role in the growth and development of the manufacturing sectors in most economies. Their output contributes significantly to the quality, cost and delivery speed of final manufactured parts. Unfortunately, the South African Tool, Die and Mould-making manufacturers have not been competing on the local or global market in a significant way. This reality has hampered the productivity and growth of the sector thus attracting intervention. The paper explores the shortcomings South African toolmakers have to overcome to restore their competitive position globally. Results from a global benchmarking survey on the tooling sector are used to establish a roadmap of what South African toolmakers can do to become a productive, World Class force on the global market.Keywords: competitive performance objectives, toolmakers, world-class manufacturing, lead times
Procedia PDF Downloads 519203 Multi-Band, Polarization Insensitive, Wide Angle Receptive Metamaterial Absorber for Microwave Applications
Authors: Lincy Stephen, N. Yogesh, G. Vasantharajan, V. Subramanian
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This paper presents the design and simulation of a five band metamaterial absorber at microwave frequencies. The absorber unit cell consists of squares and strips arranged as the top layer and a metallic ground plane as the bottom layer on a dielectric substrate. Simulation results show five near perfect absorption bands at 3.15 GHz, 7.15 GHz, 11.12 GHz, 13.87 GHz, and 16.85 GHz with absorption magnitudes 99.68%, 99.05%, 96.98%, 98.36% and 99.44% respectively. Further, the proposed absorber exhibits polarization insensitivity and wide angle receptivity. The surface current analysis is presented to explain the mechanism of absorption in the structure. With these preferable features, the proposed absorber can be excellent choice for potential applications such as electromagnetic interference (EMI) shielding, radar cross section reduction.Keywords: electromagnetic absorber, metamaterial, multi- band, polarization insensitive, wide angle receptive
Procedia PDF Downloads 341202 Loud Silence: A Situation Analysis of Youth Living with Hearing Impairment in Uganda
Authors: Wandera Stephen Ojumbo
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People living with hearing impairment in Uganda are one of the most excluded minority groups in the country. The Uganda National Association of the Deaf estimates that deaf people make up 3.4% of Uganda’s 43 million people. Deaf Children and youth often appear withdrawn because they face social stigma. In 2009, photojournalist Stephen Wandera Ojumbo conducted an exhibition in Kampala titled “Silent Voices with colourful Hearts” showcasing the life of deaf children at Uganda School for the Deaf, Ntinda, in order to create awareness of their plight, raising funds for the construction of a vocational centre for the deaf that didn’t continue their education due to: lack of funds, non-inclusive educational institutions, and for those who cannot read and write. These children, whose lives were exhibited in 2009, are currently youths. In Uganda, there are just five primary schools for the deaf (three of these are located in Kampala, the capital city), and barely five secondary schools for the deaf. At the moment, some deaf children only receive special needs training equivalent to primary seven levels and the majority don’t make it to secondary school education level due to the fact that English is a second language to them. There is a communication gap between speaking parents and deaf children, which leads to the breakage of family bonds. The deaf youth run away from their homes to form a community where they can communicate freely. Likewise, employment opportunities for the deaf are equally very limited. It’s for this reason that a follow-up photo exhibition was conducted to expose more about what the youthful deaf people and their guardians go through in Uganda to get jobs, live and fit in the community, how they communicate and get understood, bonding with families instead of running away to bond with fellow deaf persons. The photo exhibition under the theme “Loud Silence” was significant in showcasing the ability of deaf youths in Uganda and eliciting solutions to make a more inclusive society for the deaf. It is hoped that partners in development will join in for intervention. The methodology used included individual interviews with the deaf youth and their parents and caretakers; photography at household and community levels; document review at organizations working with the deaf; observations; and key informant interviews with relevant personnel working with the deaf. Some of the major findings include: i) Effective sign language communication is key in deaf education, family bonding, and developing a sense of belonging; ii) Love and intimacy can keep the deaf bound together; iii) Education is important; everybody should struggle even if alone; iv) Games and sports are a unifying factor and most loved among the deaf; and v) better communication skills build confidence in deaf youth. In conclusion, concerted efforts are still needed to make Uganda schools more inclusive for deaf persons. This will enable a secure future for deaf youths.Keywords: deaf, education, excluded, photo exhibition
Procedia PDF Downloads 88201 Experimental Study on Stabilisation of a Soft Soil by Alkaline Activation of Industrial By-Products
Authors: Mohammadjavad Yaghoubi, Arul Arulrajah, Mahdi M. Disfani, Suksun Horpibulsuk, Myint W. Bo, Stephen P. Darmawan
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Utilising waste materials, such as fly ash (FA) and slag (S) stockpiled in landfills, has drawn the attention of researchers and engineers in the recent years. There is a great potential for usage of these wastes in ground improvement projects, especially where deep deposits of soft compressible soils exist. This paper investigates the changes in the strength development of a high water content soft soil stabilised with alkaline activated FA and S, termed as geopolymer binder, to use in deep soil mixing technology. The strength improvement and the changes in the microstructure of the mixtures have been studied. The results show that using FA and S-based geopolymers can increases the strength significantly. Furthermore, utilising FA and S in ground improvement projects, where large amounts of binders are required, can be a solution to the disposal of these wastes.Keywords: alkaline activation, fly ash, geopolymer, slag, strength development
Procedia PDF Downloads 267200 The Use of Degradation Measures to Design Reliability Test Plans
Authors: Stephen V. Crowder, Jonathan W. Lane
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With short production development times, there is an increased need to demonstrate product reliability relatively quickly with minimal testing. In such cases there may be few if any observed failures. Thus it may be difficult to assess reliability using the traditional reliability test plans that measure only time (or cycles) to failure. For many components, degradation measures will contain important information about performance and reliability. These measures can be used to design a minimal test plan, in terms of number of units placed on test and duration of the test, necessary to demonstrate a reliability goal. In this work we present a case study involving an electronic component subject to degradation. The data, consisting of 42 degradation paths of cycles to failure, are first used to estimate a reliability function. Bootstrapping techniques are then used to perform power studies and develop a minimal reliability test plan for future production of this component.Keywords: degradation measure, time to failure distribution, bootstrap, computational science
Procedia PDF Downloads 531199 A Comparative Assessment of Industrial Composites Using Thermography and Ultrasound
Authors: Mosab Alrashed, Wei Xu, Stephen Abineri, Yifan Zhao, Jörn Mehnen
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Thermographic inspection is a relatively new technique for Non-Destructive Testing (NDT) which has been gathering increasing interest due to its relatively low cost hardware and extremely fast data acquisition properties. This technique is especially promising in the area of rapid automated damage detection and quantification. In collaboration with a major industry partner from the aerospace sector advanced thermography-based NDT software for impact damaged composites is introduced. The software is based on correlation analysis of time-temperature profiles in combination with an image enhancement process. The prototype software is aiming to a) better visualise the damages in a relatively easy-to-use way and b) automatically and quantitatively measure the properties of the degradation. Knowing that degradation properties play an important role in the identification of degradation types, tests and results on specimens which were artificially damaged have been performed and analyzed.Keywords: NDT, correlation analysis, image processing, damage, inspection
Procedia PDF Downloads 547198 Basketball Game-Related Statistics Discriminating Teams Competing in Basketball Africa League and Euroleague: Comparative Analysis
Authors: Ng'etich K. Stephen
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Abstract—Globally analytics in basketball has advanced tremendously in the last decade. Organizations are leveraging the insights to improve team and player performance and, in the long run, generate revenue out of it. Due to limited basketball game-related statistics in African competitions, teams are unaware of how they compete with other continental basketball teams. The purpose of this study is to evaluate the regional difference in basketball game-related statistics between African teams that played in the newly formed league, the basketball African league and the European league. The basketball African league, a competition created through the partnership between NBA and FIBA, offers a good starting point since it has valuable basketball metrics to analyze. This study sought to use multivariate linear discriminant analysis to identify the game-related statistics that discriminate the teams in Euro league and the basketball African league.Keywords: basketball africa league, basketball, euroleague, fiba, africa
Procedia PDF Downloads 100197 Gamification of a Business Intelligence Tool
Authors: Stephen Miller
Abstract:
The act of applying game mechanics and dynamics (which have been traditionally used in video games) into business applications is being widely trialed in an effort to make conventional business software a bit more participative, fun and engaging. This new trend, named ‘gamification’ has its believers and of course, its critics who still need convincing that the concept is an effective and beneficial business tool worthy of investment. The literature reveals that user engagement of business intelligence (BI) tools is much lower than expected and investors are failing to get a good return on their investment (ROI). So, a software prototype will be designed and developed to add gamification to a BI tool to determine its effect upon the user engagement levels of test participants. The experimental study will be evaluated using the comprehensive User Engagement Scale (UES) to see if there are improvements in areas such as; aesthetics, perceived usability, endurability, novelty, felt involvement and focused attention. The results of this unique study should demonstrate whether or not ‘gamifying’ a BI tool has the potential to increase an individual’s motivation to use BI software more often.Keywords: business intelligence, gamification, human computer interaction, user engagement
Procedia PDF Downloads 585196 Control of a Stewart Platform for Minimizing Impact Energy in Simulating Spacecraft Docking Operations
Authors: Leonardo Herrera, Shield B. Lin, Stephen J. Montgomery-Smith, Ziraguen O. Williams
Abstract:
Three control algorithms: Proportional-Integral-Derivative, Linear-Quadratic-Gaussian, and Linear-Quadratic-Gaussian with the shift, were applied to the computer simulation of a one-directional dynamic model of a Stewart Platform. The goal was to compare the dynamic system responses under the three control algorithms and to minimize the impact energy when simulating spacecraft docking operations. Equations were derived for the control algorithms and the input and output of the feedback control system. Using MATLAB, Simulink diagrams were created to represent the three control schemes. A switch selector was used for the convenience of changing among different controllers. The simulation demonstrated the controller using the algorithm of Linear-Quadratic-Gaussian with the shift resulting in the lowest impact energy.Keywords: controller, Stewart platform, docking operation, spacecraft
Procedia PDF Downloads 51