Designing of an intelligent fuzzy logic system for accretion prevention in Sponge iron SL/RN rotary KILN based 100TPD DRI process

Sponge iron is an intermediate product of steel formed during direct reduction of iron ore with aid of regulated temperatures and pressures within a rotary kiln. The greatest challenge is the direct measurement of kiln shell temperatures due to the catastrophic accumulation of sintered particles of solid bed which form rings at places along the length of the kiln thus hindering material flow. The accretion reduces productivity, damage kiln lining and reduces the production period as well as reduction in product quality. This process requires a controller which will be able to control with imprecise and partial data input; and be able to achieve the desired product quality under dynamic process conditions thus a Fuzzy Controller was used for the proposed design. The main goal of the research was to predict the rate of accretion build up within the kiln and minimize it with aid of a Fuzzy Control System cascaded to an already existing Programmable Logic Controller. A 16.2% build up rate was achieved as compared to the most appreciated 27% thus nearly a 10% decrease, a result which can improve the campaign period by approximately 48 hours which will be a 200 tons of sponge iron

Development of a resource agent for an e-manufacturing system

Due to globalisation and distributed manufacturing systems the development and manufacture of products is no longer an isolated activity undertaken by either one discipline or a single organization but has become a global process. Using e-manufacturing companies can now outsource to manufacturers outside their geographical area and make them dependent on the production capabilities and responsiveness of the suppliers. Hence there is need for the suppliers to provide reliable information on the state of the orders being processed. E-manufacturing promises companies to exchange the required information with their suppliers by increased visibility to the shop floor and providing a platform for information interchange. The paper discusses the development of an e-manufacturing resource agent to enable manufactures to predict the probability of their outsourced machinery being available and the probability to complete an order without having a breakdown. The Maintenance Free Operation Period (MFOP) method is used to develop the agent. This means that the manufacturer will be expected to have a guarantee that no unscheduled maintenance activities will occur during each defined period of operation with the predefined level of confidence

Investigation of the effects of lubricant fat content on drawn copper wires

The Lean Manufacturing goal of reducing waste and increasing productivity has made it a necessity to produce good quality products in manufacturing industries at a low cost. In the cable manufacturing companies this can be achieved by optimising the wire drawing process. One way to meet the desired quality of the drawn wires is to improve lubricant efficiency through installation of an automatic, continuous lubricant fat content control system on the drawing machine. The paper shows a method of finding the optimum lubricant concentration for producing good quality copper wires using Taguchi experiments. Taguchi experiments are employed to analyse the effects of different lubricant fat content levels on the tensile strength and lubricant temperature. The results from the experiments indicated that the tensile strength of the wire is affected by low lubricant fat content. The lower the lubricant fat content: the lower the tensile strength drawing lubricant resulting in numerous wire breakages that affect the quality of the final product, namely the cable

Design of an automated grinding media charging system for ball mills

The parameters of mill load (ML) not only represent the load of the ball mill, but also determine the grinding production ratio (GPR) of the grinding process. Monitoring and recognition of milling conditions have significant effect on the operating efficiency, product quality, and energy and grinding media consumption for the milling circuit. This paper presents an automated grinding media charging system incorporating a multi-agent system developed in Java Agent Development Environment (JADE). A control logix program is designed to determine the precise quantities of grinding media to be charged in an incremental manner such that shock loading is avoided. The multi-agent system created in JADE monitors the power drawn and the mill load of the ball mill such that proper charging conditions are established. High quality of the regulation process is achieved through utilization of the control logix and the multi-agent system

Model reference adaptive control system for moisture regulation in cotton ginning

Moisture content (mc) within the cotton fibre is an important aspect for all stages of the ginning process. However due to the process dynamics, mc is currently being controlled by regulating the water and air temperatures from the Humidifiers. Human intervention and lack of consistence on set-points determination has resulted in inconsistent mc during humidification. This procedure requires a control system which will be able to adjust the process set-points automatically by eliminating the need for human intervention. In this paper a robust Model Reference Adaptive Control (MRAC) system for a Samuel Jackson Humidifier is presented. This system improves upon the existing system by creating a closed loop controller with parameters that can be updated to change the response from reference model. The control parameters are then updated based on this error thus the parameters converge to ideal values that cause the plant response to match the response of the reference model

Knowledge and perceptions towards malaria prevention among vulnerable groups in the Buea Health District, Cameroon

BACKGROUND: Malaria is a public health problem especially in vulnerable groups such as pregnant women and children under five years in Cameroon including the Buea Health District (BHD). Misconceptions concerning it exist. This study assessed the level of knowledge and perceptions towards malaria control among pregnant women and mothers/caretakers of under-fives in the BHD. METHODS: A community-based cross-sectional study was conducted in the BHD in August, 2011 in five health areas. A questionnaire was used to collect data on demographic variables, knowledge and perceptions towards malaria control from 443 respondents aged 15–73 years. RESULTS: Of the 443 respondents interviewed, 99% had heard about malaria. Awareness of malaria was similar in rural (98.04%) and urban (98.97%) areas. The health facility was the most popular source of information (74%). The radio, television, tracts/posters and the community relay agents (CRAs) all informed significantly higher proportions of respondents in the urban than rural communities (P <0.05). Overall, 92% of respondents had the right perception of malaria and 88% knew at least one correct sign/symptom of malaria. The most recognised sign of malaria was fever. When all aspects of malaria were considered, majority (88%) of respondents had good levels of knowledge on malaria. The level of good knowledge in respondents with ≥ secondary school education (91%) was significantly higher (P = 0.01) than in those with ≤ primary school level (83%). Overall, 99% had heard about insecticide treated nets (ITNs); 99% perceived ITNs as a good means to prevent malaria; most respondents (57%) used ITNs mainly for protection against mosquito bites while 48% used them for protection against malaria. CONCLUSION: Respondents with no formal education had a poor level of knowledge on malaria. Hence, new strategies for sensitization messages involving their active participation need to be developed

Adolescent and young adult preferences for financial incentives to support adherence to antiretroviral therapy in Kenya: A mixed methods study

INTRODUCTION: To develop a patient-centred financial incentive delivery strategy to improve antiretroviral treatment adherence in adolescents and young adults (AYA) living with HIV in Kisumu, Kenya, we conducted a mixed methods study exploring preferences. METHODS: A discrete choice experiment (DCE) and focus group discussion (FGD) were conducted simultaneously to identify preferences for five incentive delivery strategy features: value, eligibility, recipient, format and disbursement frequency. We used consecutive sampling to recruit AYA (14-24 years) living with HIV attending three health facilities in Kisumu, Kenya. We calculated mean preferences, willingness to trade, latent class membership and predictors of latent class membership. The FGD explored preferred incentive features, and, after deductive and inductive coding, qualitative findings were triangulated with DCE results. RESULTS: Two hundred and seven AYA living with HIV (46% 14-17 years, 54% 18-24 years; 33% male sex, 89% viral load \u3c50 copies/ml) were recruited to the study (28 October-16 November 2020). Two distinct preference phenotypes emerged from the DCE analysis (N = 199), 44.8% of the population fell into an immediate reward group, who wanted higher value cash or mobile money distributed at each clinic visit, and 55.2% fell into a moderate spender group, who were willing to accept lower value incentives in the form of cash or shopping vouchers, and accrued payments. The immediate reward group were willing to trade up to 200 Kenyan Shillings (KSH)-approximately 2 US dollars (USD)-of their 500 KSH (∼5 USD) incentive to get monthly as opposed to accrued yearly payments. The strongest predictor of latent class membership was age (RR 1.45; 95% CI: 1.08-1.95; p = 0.006). Qualitative data highlighted the unique needs of those attending boarding school and confirmed an overwhelming preference for cash incentives which appeared to provide the greatest versatility for use. CONCLUSIONS: Providing small financial incentives as cash was well-aligned with AYA preferences in this setting. AYA should additionally be offered a choice of other incentive delivery features (such as mobile money, recipient and disbursement frequency) to optimally align with the specific needs of their age group and life stage

E-manufacturing - the roadmap for South African manufacturers

The original publication is available at http://www.isem.org.za/index.php/isem/isem2011Conference of the ISEM 2011 Proceedings, Stellenbosch, South Africa, 21 - 23 September 2011.Conference theme - Innovative Systems Thinking: Unravelling Complexity for Successful SolutionsGlobalization and the internet have given customers a wide choice of products to choose from and they are now expecting a lot from products. Customers are demanding more value, less risk and better integration of products hence products now have a shorter product life cycle. E-manufacturing can help companies to optimize the use of production assets, reduce production cycle times and costs to meet these customer requirements. The paper shows factors that influenced an economy to successfully implement an emanufacturing model that transformed the economy from a struggling economy into an advanced economy. E-manufacturing models are discussed. Taiwan is used as a case study of how engineering chain can be utilized for SMEs to enjoy equally or even higher competitive advantage than their larger competitors by appropriately utilizing external networks. The situation in South Africa shows that the country can benefit from the growth of SMEs and e-manufacturing if networks and a culture of sharing information are built among SMEs and companies in the country.The Industrial, Systems and Engineering Management (ISEM) conference is a joint initiative between the Southern African Institute for Industrial Engineering (SAIIE), INCOSE (South Africa) and the Graduate School for Technology Management at the University of Pretori