383 research outputs found
Sort by
Neural Network Breakout Prediction Model for Continuous Casting
No full textContinuous casting is a process in which liquid steel is cooled in a bottomless mould into semi-finished steel products called billets, blooms or slabs depending on their cross section. In the process of continuous casting, two of the major problems encountered are cracks and breakouts. Breakouts usually result in temporary shutdown of the caster and huge amounts of downtime.
Primary cracks which form before the solidifying strand exits the
mould, are invariably linked to breakouts. Controlling primary cracks results in reduced chances of breakouts. This work aims at designing a breakout prediction neural network model. In this paper, a two-layer feed forward backpropagation neural network
model is developed for predicting the existence of primary cracks that might lead to a breakout. The network obtains its inputs in form of temperature values from rows of thermocouples attached
to the mould tube. Based on solidification characteristics of steel,the neural network is supplied with various inputs (of temperature values) and targets and is trained to predict the crack status in the
mould. Training is performed using the Levernberg-Marquardt (trainlm) training algorithm, and the log sigmoid transfer
function was used for both the hidden and output layer. The output from this neural network was a logical 1 (if a primary crack is present) and a logical 0 (if no primary crack is present). The neural network model is validated by simulating in MatLab/Simulink
Modelling the effects of chemotherapy and relapse on the transmission dynamics of leprosy
No full textThis is an Open Access article distributed under the terms of the Creative
Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly citedPurpose: Although there is a declining trend in the global burden of leprosy, there are 15 countries in Asia and Africa
which account for 94% of the global total of the new-case detection rate. Here, we assess the impact of different
intervention strategies aimed at leprosy eradication through targeting non-symptomatic and symptomatic individuals.
Methods: We develop a mathematical model of leprosy transmission and treatment amongst symptomatic and
non-symptomatic, in order to investigate the effects of leprosy relapse cases, case finding of non-symptomatic
individuals and compliance to therapy of individuals administered with treatment. Comparison theory has been
qualitatively used to analyze the global stability of the disease-free equilibrium. With the aid of centre manifold theory,
the local stability of the endemic equilibrium has been investigated. Population-level effects of increased case
findings and high treatment rate (guaranteed by compliance and completion of therapy via educational campaigns)
are evaluated through numerical simulations and presented in support of the analytical results.
Results: Comprehensive and qualitativemathematical analysis of the model reveals that, the disease-free equilibrium
is globally, asymptotically stable whenever the reproductive number is less than unity. Further, we have established
that the model has a locally, asymptotically stable endemic equilibrium when the reproductive number is greater, but
close to unity. Numerical simulation suggests that case finding of non-symptomatic leprosy carriers, greater that 40%
is necessary for reducing leprosy prevalence and maybe useful on attaining leprosy eradication.
Conclusions: At its best, the study suggests that high level of case finding targeting non-symptomatic and
symptomatic individuals, together with high level of compliance by individuals on treatment, may have a substantial
effect on controlling leprosy relapses and possible may assist on attaining leprosy eradication
Critical Analysis Of Behavioural Training Method For Supply Chain Operation Reference (SCOR) Model Compliant Supply-Chain-Management (SCM)
No full textCIE42 Proceedings, 16-18 July 2012, Cape Town, South AfricaSupply-Chain-Management (SCM) is a discipline introduced in order to shift from rule based procurement systems to an integrated SCM system. Managing Supply-Chain (SC) operations is thus critical to any company?s ability to compete effectively. Virtually all modern organizations accept that a well-trained SCM team is a critical success factor. Formal training of SC professionals represents substantial investment for organisations. Cognitive
training methods offer controlled, secure, and risk free environments of instruction. In
contrast, behavioural training methods offer more practical instruction and application
opportunities to the trainees and thus have ?hands-on? advantage over cognitive SCM
training. The various methods under behavioural approach allow trainees to ?behave? under a set of realistic circumstances to facilitate effective skills development. Globalization and technological advancements have led organizations to shift toward computer based simulations, using interactive multimedia and virtual reality, as a SCM training tool. This paper presents findings of a literature study and a simulation training evaluation for a
business game (The Fresh Connection?) played as part of a university course. Cross
functional decision making, as prescribed by the Supply Chain Operation Reference (SCOR)
model, is emphasised. Results of this study have impact of highlighting benefits of
computers in simulation training of today?s SC professional.SAII
Important Utilities and Infrastructure in Support of Trade and Productive Capacity Utilisation.
No full textPublished in the Chronicle Newspaper of December 6,2012 on the Productivity Column
Lean Six Sigma Application for Sustainable Production: A Case Study for Margarine Production in Zimbabwe
No full textInternational Journal of Innovative Technology and Exploring Engineering (IJITEE)
ISSN: 2278-3075, Volume-1, Issue-5, October 2012Lean Six Sigma is an integration of two World Class Manufacturing improvement philosophies(Lean Manufacturing and Six Sigma) that help organizations improve their performance and competitiveness. The principles are applied to margarine
manufacturing. The Value Stream Mapping tool is used to map the processes and the Six Sigma?s Define, Measure, Analyze,Improve and Control (DMAIC) methodology applied to attain improvements. The Current State Map (CSM) is drawn and using the DMAIC methodology, the Future State Map (FSM) is drawn. The production line ultimately achieves improvements in cycle times and in Value Added time ratio from 39% to 94%. There are envisaged improvements of up to 86% on cycle times for individual processes
Marula Nut Decortications Machine Development to Grow Industry and Sustain Rural Livelihoods in Chivi and Masendu Wards in Zimbabwe
No full textWorking Papers presented at The Third Annual International Conference: Growing Industries in Townships and Under-Developed Neighbourhoods, Soweto Campus. Dates: 15?16 May 2012This research focuses on developing the entrepreneurial skills and capacities of the marginalised and disadvantaged groups (especially women and orphans) in countryside communities. It seeks to promote the development of sustainable community-based natural product enterprises and to provide guidance in developing and implementing programmes on developing entrepreneurship skills and culture at the community level by providing mechanisation technology for cracking Marula fruit nuts. The researchers seek to develop the concept of a Community-Based Enterprise (CBE), maintaining that it provides a potential strategy for sustainable local development. The research established that most people in rural areas depend on the forest and on other natural resources for their daily livelihoods. However, they generally use these resources in a subsistence mode, and hardly harness the optimum potential of the resource nor do they generate a good income and secure employment for themselves. Such a subsistence approach to using the products of natural resources is an attributed factor for the continuation of rural poverty and the degradation of the resource base. There is little incentive for these people to conserve and manage the resources. This led to the researchers? focus on the establishment of Marula natural products enterprises development as a basis for the generation of income and employment for local people, and the sustainable management of natural resources. Research has shown that the poorest communities need entrepreneurship skills to enable them to establish and develop sustainable natural product enterprises. Entrepreneurship development provides the natural resources-dependent communities with the skills and competencies necessary to address enterprise
67
challenges, and to tap into the opportunities in the long run through initiating enterprises with or without external support. Researchers have established that little work in Zimbabwe has been done to increase the rate of production in Marula nut cracking. The methodology used included conducting a survey and participatory workshops in the two zoom sites of Masendu and Chivi to establish the feasibility of using the Marula tree and fruit as the focal economic driver. The workshops provided pertinent information which will be vital in generating the Marula nut cracking machine design as a platform to fostering entrepreneurship for economic sustainability in the communities
School/Community Libraries: is the Duality Possible?
No full textPaper presented at the Drilldown
Session ?E? of the Africa Library Summit 2011 held at Misty Hills Hotel, Conference Centre and Spa, Muldersdrift, Gauteng, South Africa from Wednesday 11th to Friday 13th May 2011School/Community libraries are veritable tools for rural development. Their all-inclusive and dual services have evidenced this to everyone in the communities they serve who might be interested in their services. Children are particularly a distinct and active group benefitting from
the services provided by school/community libraries. They use the libraries for recreational reasons through reading books and magazines, listening to book talks and stories and participating in library-based games and other light activities. Through such library services,children grow up already used to reading and libraries, having established a good base for
ardent readers as they slowly enter adulthood. Adults alike, also enjoy the library activities that usually come in packages for recreational, educational, cultural and informational reading. Other activities such as study circles offer the adults an opportunity to participate in the lifelong continuing education process. The duality of school/community libraries is therefore not only possible, but an emerging phenomenon in rural Africa
World Class Manufacturing status Assessment for a Margarine Producing Company in Zimbabwe
No full textThe world has become global in the way goods and services are produced and marketed. The stiff global competition faced by these companies necessitates a need to embark on radical strategies in the form of World Class manufacturing philosophies to survive, make profit and remain competitive. While companies in developing countries strive to adopt these World Class Manufacturing (WCM) philosophies into their production process, there is often lack of a measure on their progress towards world class manufacturing status besides the improvement in
productivity. This paper?s focus is on how companies can assess their progress in terms of achieving a world class manufacturing
status. The research starts with an assessment of the world class status of the company that has adopted best manufacturing
practices. A Current State Radar Chart (CSRC) is drawn to see the company?s position on the radar. Researches methods
(questionnaires, interviews, company audit) are used to identify wastes according to WCM. WCM techniques were used to
minimise wastes. A Future State Radar Chart (FSRC) is drawn to assess the improvements made. The company was operating its
margarine production process at 35% of a world class process. The major waste identified was the downtime. Downtime contributed to 74% of the total available time leaving production only 26% of the available time. WCM techniques realised a reduction in downtime by 30% and increased the available time for production to 56%. These changes achieved a 56% of a world class process on the FRC drawn
International Open Access Week Report 2012: National University of Science and Technology
No full textPresented after the International Open Access week at NUST from the 29th of October to the 2nd of November 2012.This year's open access activities were geared towards promoting the concept of open access by targeting various stakeholders in the University community which included academic staff, university administrators and students. The main thrust was the promotion of the University's institutional repository (NuSpace) as a tool for open access as well as advocating for the adoption and use of Open Access resources. It was hoped that as a result the campaign, the population and awareness of the Institutional Repository as a scholarly communication tool would improve. The campaign set the tone to advocate for the adoption of an Open Access policy at the University. At the end of the campaign researchers at NUST were also expected to contribute to the open access movement by publishing in Open Access Journals
Assessing the Effects of Estrogen on the Dynamics of Breast Cancer
No full textThis is an open access article distributed under the Creative Commons Attribution
License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly
cited.Worldwide, breast cancer has become the second most common cancer in women. The disease has currently been named the
most deadly cancer in women but little is known on what causes the disease. We present the effects of estrogen as a risk factor on
the dynamics of breast cancer. We develop a deterministic mathematical model showing general dynamics of breast cancer with
immune response. This is a four-population model that includes tumor cells, host cells, immune cells, and estrogen. The effects of
estrogen are then incorporated in the model. The results show that the presence of extra estrogen increases the risk of developing
breast cancer