Ovundah King Wofuru-Nyenke

Bio: Ovundah King Wofuru-Nyenke is an academic researcher. The author has contributed to research in topics: Supply chain & Bottling line. The author has an hindex of 1, co-authored 2 publications receiving 4 citations.

Advancements in Sustainable Manufacturing Supply Chain Modelling: a Review

Abstract: Managers at various echelons of supply chains are continuously faced with problems of examining and improving supply chain processes with the aim of improving productivity and customer service level, while reducing emissions and total costs simultaneously. This study is aimed at presenting the trends in sustainable manufacturing supply chain modelling in order to establish the modelling approaches which have predominantly been used for improving manufacturing supply chains from years 2010 to 2020. The study employs the systematic literature review methodology for reviewing articles published within the 11-year period. We proffer a classification approach for manufacturing supply chain models, grouping these models into mathematical models, simulation models, hybrid models, and their subcategories. The results showed that though there is a rising trend in the use of simulation and hybrid models, mathematical models have been used more for sustainable manufacturing supply chain modelling. The rise in the use of simulation and hybrid models can be explained by the fact that these models tend to handle uncertain and stochastic data better than mathematical models, which perform better with deterministic data. This research will aid other researchers in recognising the current gaps in manufacturing supply chain modelling in order to identify future research directions.

Design Analysis of a Portable Manual Tyre Changer

Abstract: DOI: http://dx.doi.org/10.24018/ejers.2020.5.11.2224 Vol 5 | Issue 11 | November 2020 1 Abstract — In this paper, an efficient, affordable, and portable manual automobile tyre changing tool was designed. The tool operates on the principle of second-class levers, where the load to be overcome is situated between the fulcrum and the effort point. The mechanical advantage (MA) of the bead breaker arm and pry bar assembly of the tool was determined to be 11.5. The standard tube size of the bead breaker arm that can withstand stress due to bending moment was determined to be a 2” (50mm) diameter Schedule 80 steel tube. Also, the dimensions of the standard hexagonal bolts to be used at the fulcrum and load point of the bead breaker arm are M12 × 1.5 × 75 mm, while the standard size of hexagonal nuts to be used with the bolts is M12 × 1.5 mm with a height of 10mm. Moreover, the mechanical advantage (MA) of the mount/demount arm and pry bar assembly of the tool was determined to be 5.22. Also, by comparing the angles of twist of two sizes of the mount/demount arm when the tool is used in mounting or demounting a tyre on a 16” × 7” wheel rim, the standard size of the mount/demount arm that can withstand stresses due to bending moment and torsional moment was determined to be a 60mm × 60mm × 5mm square tube. The cost of materials needed to fabricate the tyre changer summed up to ₦21,000. Ergo, the design provides an alternative portable and relatively affordable tyre changing tool that can be afforded by tyre technicians across Nigeria, and other developing or underdeveloped countries.

Waste and Cost Reduction for a Water Bottling Process Using Lean Six Sigma

Abstract: In this paper, Lean Six Sigma tools and techniques were utilized to determine the root causes of waste in a water bottling process and proffer solutions to remove these sources of waste in order to produce only standard quality items with minimal to zero waste generated, and also to attain a reduction in production cost. The Value Stream Map (VSM) tool was used to highlight the sources of waste in the current state of operations at the plant, as well as to proffer an improved future state of the production processes at the plant. Also, the Define-Measure-Analyze-Improve-Control (DMAIC) framework of Lean Six Sigma methodology was employed to statistically analyze the root causes of waste in the plant. The analysis showed that the major sources of waste which constitute approximately 80 per cent of waste in the plant are water volume variation, alignment error in the shrink wrapping machine and manual inspection. After implementation of the proposed solutions, manufacturing lead time and cycle time are expected to reduce by approximately 42.1 per cent and 22.2 per cent respectively, with a reduction of 2 quality inspectors in the bottling process, leading to a drop in labour cost.

Predicting demand in a bottled water supply chain using classical time series forecasting models

Abstract: In this paper, various classical time series forecasting methods were compared to determine the forecasting method with the highest accuracy in predicting demand of the 50cl product of a bottled water supply chain. The classical time series forecasting methods compared are the moving average, weighted moving average, exponential smoothing, adjusted exponential smoothing, linear trend line, Holt’s model, and Winter’s model. These methods were evaluated to determine the method with the least Mean Absolute Deviation (MAD) value and hence the highest forecasting accuracy. From the results, the weighted moving average forecasting method had the lowest MAD value of 1,987, making it the forecasting method with the highest accuracy for predicting the 50cl bottled water demand. While the exponential smoothing forecasting method had the highest MAD value of 2,483, making it the forecasting method with the least accuracy for predicting the 50cl bottled water demand. This research provides a procedure for aiding supply chain analysts in implementing demand forecasting using classical time series forecasting models.

Literature review on the usage of six sigma techniques for improvement of quality in soft drink beverage and bottling industries

Abstract: The main goals of a manufacturing plant is to improve quality, throughput and increase productivity by reducing ineffective time. In order to do so various areas needs to be looked at and one such focus is on quality improvement, quality has various dimension’s and meeting all these dimension require a sound approach like Six Sigma. The soft drink beverage industry has a complex manufacturing process and there are strict quality measures due to the direct relation which it has with its consumers. In order to accomplish such a need six sigma approach is essential. In regard to the beverage industry quality issues starts of from carbon dioxide yield to bottle filling issues. This study focusses on bringing in different literature which have used six sigma tools and techniques in the bottle and beverage industry. Based on the study it was found techniques such as pareto analysis, fish bone diagram, design of experiment, analysis of variance (ANOVA), control charts are widely used. This is done in order to provide a sound framework on what techniques can be applied when an issue on quality arises.

Development of Conceptual Vehicle All-Wheel-Nuts Remover

Abstract: As the standard of living in Malaysia has increased, most of the families have at least one vehicle, typically, car, to move easily and quickly. With the increment of the number of cars in the road, the number of cars’ problem due to tyre failure has increased. Often, the car is provided with tyre wheel nuts remover and jack for instance spare tyre replacement. Nevertheless, due to the difficulty in applying the required torque to remove the nuts, most of the time, driver rely on the tow truck and available nearest mechanic to solve the problem. This always happen to the elderly or female drivers. Based on the capability of torque application by these drivers, a vehicle all-wheel-nuts remover is designed. The remover is designed to be ergonomic to be used, easy maintenance, easy storage, easy to handle and able to remove all nuts at once. The design of the remover is based on standard pitch circle diameter (PCD) of 100 mm and 4 numbers of nuts for most of the cars available.

Green-Resilient Supplier Selection and Order Allocation Under Disruption by Utilizing Conditional Value at Risk: Mixed Response Strategies

Abstract: Two important decisions in supply chains and logistics systems design are the supplier selection and order allocation (SS&OA) problem and the vehicle routing problem (VRP). Supply disruption may reduce the capacity of suppliers, and the transportation network disruption may decrease the number of vehicles in the fleet and disrupt some routes. Also, increasing environmental regulations and environmental awareness makes companies pay more attention to green supply chain management (GSCM). In this paper, we integrate green and resilient supplier selection and order allocation decisions with vehicle routing decisions under disruption. We present a multiproduct two-stage risk-averse mixed-integer stochastic linear programming for the green and resilient supplier selection and order allocation integrated with vehicle routing (G&RSS&OA-V) problem. We consider resilient strategies before disruption, including multiple sourcing, supplier fortification, prepositioned inventory at the protected supplier, and contract with third-party logistics providers (3PLs). The objective function is to minimize the total mean-risk cost and the cost of greenhouse emissions. We use conditional value at risk (CVaR) as a risk measure to control the risk of worst-case cost. The most significant decisions of this model are the strategic decisions of determining the optimal suppliers and the operational decisions of vehicles routing under disruption simultaneously. Other decisions include determining which suppliers should be fortified, the amount to be transported to the hybrid manufacturing-distribution (HMD) center through the supplier or prepositioned emergency inventory, and the amount of lost sales. In order to validate the proposed model and its features, several numerical examples along with sensitivity analysis are performed by GAMS software, which shows the efficiency and application of the developed model, and some managerial insights are reported. The results of the sensitivity analysis show that as α increases from 0.1 to 0.9, the mean-CVaR objective function cost increases to 13.2%. As λ increases from 0.1 to 0.9, the mean-CVaR objective function cost increases to 35.6%. The increase of these two risk factors makes the proposed model more risk-averse. As the expected shortage cost increases by 150%, the mean-CVaR objective function cost increases to 36% while the amount of expected shortage decreases by 56%.

Design and Fabrication of Vehicle All-Wheel-Nuts Remover

Abstract: As the standard of living in Malaysia has increased, most of the families have at least one vehicle, typically, car, to move easily and quickly. With the increment of the number of cars in the road, the number of cars’ problem due to tyre failure has increased. Often, the car is provided with tyre wheel nuts remover and jack for instance spare tyre replacement. Nevertheless, due to the difficulty in applying the required torque to remove the nuts, most of the time, driver rely on the tow truck and available nearest mechanic to solve the problem. This always happen to the elderly or female drivers. Based on the capability of torque application by these drivers, a vehicle all-wheel-nuts remover is designed. The remover is designed to be ergonomic to be used, easy maintenance, easy storage, easy to handle and able to remove all nuts at once. The design of the remover is based on standard pitch circle diameter (PCD) of 100 mm and 4 numbers of nuts for most of the cars available.