ghanaopendata/ghanaian-research-english huggingface dataset:
An optimal transshipment scheme for oil company based in the Greater Accra Region

The problem in this thesis deals with the transportation of goods from an oil company to the consumer through intermediate warehouses referred to as the transshipment centers. A mathematical technique is used here to find a minimum cost of transporting these goods while not sacrificing the requirements of the consumers and the production capacities of the source or factory. Optimization technique such as linear programming is employed. The simplex algorithm is used and then a special transportation algorithm is discussed and again used to solve the transshipment problem. The total cost of transportation obtained is compared to the actual cost of transportation incurred by the company. It is found that a significant difference exists and certain commodities need not be transported along certain routes.

Source: KNUST
Optimal Visitation of Base Transciever Station Site: (Case Study of Vodafone Network; New Juabeng Municipality, Eastern Region, Ghana)

This research work presents a case study of the optimal visitation of Base Transceiver Station (BTS) site in a mobile communication network. The main objective is to formulate a mathematical model that takes into consideration the actual distances between the twenty four (24) BTS Site. Also to determine the optimal route for visiting the entire twenty four (24) BTS Site within the New Juabeng Municipality to minimize travelling cost, time and distance for Vodafone maintenance Engineers and entire sub-contractors working on the BTS sites. The problem is formulated as an Integer Programming Model and solution is presented via the simulated Annealing Algorithms based Meta-heuristic for the Travelling Salesman Problem. Data on distances were collected from potential length Between the BTS and with a Matlab implementation codes, results are obtained. In comparison with the existing routing system at Vodafone Network the results evince the outperformance of the simulated Annealing algorithm in terms of efficiency. In fact, the simulated Annealing results reveal a tremendous improvement in the total route length by approximately 45%.

Source: KNUST
Optimal transport pricing of inland freight for cement haulage at GHACEM Limited

Cement is a key element of modern construction and its production at Ghacem limited takes place only at Tema and Tarkoradi whiles consumption occurs across the breadth and length of Ghana. Transportation therefore plays a major role in the distribution of the product and contributes to a portion of the landed price of cement to the consumer at distant locations. This study attempts to develop a model for optimal transport pricing of inland freight for cement haulage at Ghacem limited for cement distribution in Ghana. In order to achieve the research objectives, literature on product transport pricing between firms and the consumer and the mathematical theory of linear programming for solving transportation problems were reviewed. Results of the transportation model which was undertaken with the aid of Microsoft Excel Solver 2003 application, used data of cement supply and consumption activity recorded by Ghacem in year 2010. The model revealed and optimal transport pricing solution and also indicated a pattern of routes from different sources (supply) to different destinations (demand) if transportation costs were to be minimized. Owing to its current pricing scheme known as the “mill price model”; where firms choose their locations, price their products and consumers incur the transportation cost to their demand destinations, Ghacem does not completely control the physical distribution of the product and therefore has no comprehensive transport cost model for comparison with the derived optimal transport price in this work. However, one purpose of the theory of optimal pricing using the transportation model is to predict what the optimal price should consist of in terms of cost, making the theory fit for empirical development and practical application as had been carried out in this case with the goal of helping to reduce the net cost of cement to consumers at distant locations.

Source: KNUST
Optimisation of hydropower generation at Volta River Authority during off-design conditions

Volta River Authority (VRA) operates two hydropower plants as part of its power system; one of which consists of six turbine-generator units at Akosombo with total capacity of 9 12MW and the other a downstream plant of four turbine-generator units of total capacity of 160MW at Kpong. The operation of the downstream plant depends on the total discharge from the Akosombo plant to create the head required. The discharge per unit at the Akosombo plant is less than the discharge per unit at the Kpong plant. However, the total discharge from the Akosombo plant is more than that from the Kpong plant under normal operating conditions for all units. Running less than six units at the Akosombo plant results in inadequate head at the Kpong plant; this makes it impossible to put all four units into service at the Kpong plant. A model equation of the two power plants has been determined and used for the estimation of the plant efficiency. The model equation serves as the objective equation and is used for the optimisation of the system. A computer program was developed for determining the combinations of the units at the Akosombo and the Kpong plants that would allow for optimum generation of power. The Search method of optimisation was employed and coded in Visual Basic programming language. The simulated results were validated using the given operation data. The output of the program includes the number of turbines that can be run within a day on hourly basis to obtain the optimum power output, .taking into consideration the set of constraints of the system. Estimated combinations for six days are provided. The result of this project or thesis is recommended for use as a guide in the operation of the Akosombo and Kpong Hydropower plants by VRA when the headwater level at Akosombo dam is less than the normal recommended minimum of 75.59m. It is expected that by the use of this program, optimal power output shall be obtained at low available water levels. The programme can be used to predict future available power.

Source: KNUST
Optimal Water Treatment: A Case Study of Kpong Headworks

Water is one of the most essential requirements to life and most human activities involve the use of water in one way or another. It is now universally accepted that providing a community with safe water, epidemics of water-borne diseases can be prevented. Untreated surface water has long been known to be the source of much human illness. Over one billion people each year are exposed to unsafe drinking water due to poor source water quality and lack of adequate water treatment. The primary objective of any water supply scheme is to supply safe water in sufficient quantity. The main objective of this study is to develop a water treatment cost model at Kpong Headworks using linear programming to minimize the cost of treating water. The research showed that the factors which affect water treatment cost at Kpong Headworks includes; cost of personnel (labour), cost of electricity, cost of chemicals for treatment cost of fuel and lubricants, cost of repairs and maintenance, cost of raw water source, cost of other contractual, cost of civil structures of the treatment plant. The most influential factors which make it very expensive to treat water at Kpong Headworks are cost of chemical, cost of electricity and the cost of fuel. The study however revealed that, the average seasonal water treatment cost of Gh¢ 5576308.21 and Gh¢ 11633320.30 for dry and wet seasons respectively can be optimized to Gh¢ 1160000.00 in the dry season and Gh¢ 1200000.00 in the wet season to deliver the same quantity of water to consumers in each season. Sensitivity analysis performed showed that the model developed will not minimize the total cost if the unit price of a bag of chemical, unit price of electricity and price of a litre of fuel in the objective function is increased by Gh¢ 1.00 in the dry season and Gh¢ 2.25 in the wet season.

Source: KNUST
Optimal work scheduling for nurses at a regional hospital

Since the inception of the National Health Insurance Scheme (NH1S) the number of patients attending hospitals has gone up significantly. On the other hand, the number of health personnel such as nurses has reduced due to brain drain. In this study we address an aspect of the problem of increased pressure on heath personnel nurses at Komfo Anokye Teaching Hospital (KATH) by coming out with an optimum schedule of work using an integer programming model. On the construction and implementation of such a model, it was found that the number of shifts for all the nine wards had drastically reduced. This project is about Optimal Work Schedule For Nurses At A Regional Hospital. As a case study data was collected from the Surgical Wards of Komfo Anokye Teaching Hospital(KATH) Kumasi.

Source: KNUST
Optimisation of profit in the artisanal marine fishing: a case study of Sekondi fishing harbour.

The importance of the fisheries sector in the socio-economic development of Ghana cannot be overemphasised. Any organisation set up aims at maximisation of profit from its investment from minimum cost of objective function. This research work applies the concept of simplex method; as aspect of linear programming to solving industrial problems with the aim of maximising profit. The artisanal marine fishing industry in the Sekondi fishing harbour specialises in different types of canoe fishing. A purposive sampling technique with questionnaires was used to select two types of canoe fishing, namely Ali/Poli/Watsa(APW) and Hook and Line units were used to determine the profitability and viability of each method for both major and minor upwelling seasons. The problem was formulated as linear programming model and solution is presented using the simplex method via PHP on line software to maximise the profit of the two fishing units. Based on the analysis of the data collected, it was observed that both APW and Hook Line fishing units are profitable in major and minor seasons. Also it was observed that equal quantities of fish must be produced (catch) to maximise a certain level of profit.

Source: KNUST
Optimising the Transshipment Problem of Blue Sky Limited

Transshipment, when possible, can be used as one effective way to reduce total inventory and increase service level in a distribution system. Essentially, transshipment allows the distribution system to take advantage of the risk pooling effect to deal with uncertain demands at different retail locations. Excess inventory at one retail location can be used to cover shortage at another location. Physically, one can interpret inventory stocking at each individual location as being “pooled” together to meet the demands at any other location within the distribution system. As such, the use of transhipment provides more flexibility in deploying the available inventory in the system to meet uncertain customer demand. From a management and operation perspective, a fundamental question in this problem is whether the company should move the product into the demand ports directly from the supply port, or whether the transhipment operation using an established warehouse can help to reduce the total cost to the company and increase responsiveness. From the resource utilization perspective, a transhipment system is certainly preferred as it provides a better utilization of the transporting goods. Currently, as at the time of this work, there is no such method for determining which route to be used in transporting the products by the company. The routes are chosen using guess work and by the discretion of the people in charge. For the data used for our analysis, the company using their crude approach arrived at the following conclusion; shipped the loads of 15000, 5000, 10000, 8000, 2000 and 10000 at a unit costs of GH¢15, GH¢7, GH¢10, GH¢4, GH¢3 and GH¢2 through the routes X - W2 – B, X - W2 – C, Y - W1 – A, Y – W1- B, Y - W2 – D, and Z – W2. Total cost of transporting these products was four hundred and eighteen thousand Ghana cedis (GH¢418,000.00).

Source: KNUST
Optimising ventilation to control odour in the ventilated improved pit latrine

The rate of ventilation through the vent pipe of a ventilated improved pit latrine is the main technical factor that determines its efficiency in odour control aside the maintenance and cleaning practices of the users. Even though the factors affecting the ventilation rate have been well researched, they have not been previously related in a mathematical model to quantify the relative effect of the various factors on the ventilation rate. The objective of this paper is to develop such a model that could be used to optimise and predict the ventilation rate as a function of relevant design criteria and weather conditions. The ventilation rates produced by various design modifications in an experimental ventilated improved pit latrine were measured under monitored weather conditions. A linear regression model was used to assess the relative effect of the various design modifications and the elements of weather on the ventilation rate. It was found that the diameter of the vent pipe is the most important factor which accounts for 53% of variations in the ventilation rate, followed by the external wind speed, which accounts for 25% of changes in ventilation. The provision of windows in other sides of the superstructure other than the windward side leads to a reduction of 32% in the ventilation rate and accounts for 9% of the variations in the ventilation rate. A regression model developed in this study could be used to optimise and predict the ventilation rate based on a set of design criteria and meteorological data.

Source: KNUST
Optimization framework for derogating SDCCH and TCH congestions in Liberia global system for mobile communications (GSM)

In GSM communications, congestion remains a major factor and stands as a high influence in the satisfaction of subscribers and service providers[1]. Traffic Channel (TCH) and Standalone Dedicated Control Channel (SDCCH) Congestions are two major problems faced in GSM networks. This thesis attempted to investigate the causes of SDCCH & TCH congestions, and the assessment of the current state of GSM networks in Liberia by using a Liberian GSM network‟s KPI (key Performance indicator) as case study to develop an optimized GSM network model. During the sampling and processing of the data in the investigation, a range of 49-0% was chosen as the worst call setup success rate (WCSSR). These WCSSR locations along with their various SDCCH & TCH congestion results were later plotted into bar chart graphs, and point graphs using OriginPro software. Finally, a Sugeno-Takagi KPI Optimization simulation setup was developed using Adaptive Network Fuzzy Inference System (ANFIS) model in MATLAB. The simulations compares and demonstrates the current and expected optimized network. The result shows that optimization is possible and can be almost at the maximum level in real cellular networks.

Source: KNUST
Optimization of a protocol for the evaluation of antibody responses to human papillomavirus (HPV) vaccination in low-resource settings

Introduction: Available human papillomavirus (HPV) vaccines could have an important primary role in cervical can‑ cer prevention once their long-term immunogenicity and safety are evaluated at the population level. The aim of this study was to optimize an assay to be used in evaluating the long-term durability of HPV vaccine response following a pilot vaccination of adolescent girls in Ghana. Methods: A rapid, high-throughput, indirect enzyme-linked immunosorbent assay (ELISA) was optimized for the detection and quantitation of anti-HPV L1 (late expression protein: types 6, 11, 16 and 18) immunoglobulin G (IgG) in human serum (n=89). The utility of the assay was demonstrated using serum collected from a cohort of pre adolescent girls (n=49) previously vaccinated with a quadrivalent vaccine and non-immune serum obtained from age-matched controls (n=40). Results: The assay showed good discrimination of antibody levels between cases and control sera: seroprevalence of anti-HPV IgG antibodies was signifcantly higher among vaccinated than unvaccinated girls for both HPV-16 (63.3% vs. 12.5%; p<0.001) and HPV-18 (34.7% vs. 20.0%; p=0.042), respectively. Thirty-six months after receiving the third dose of vaccine, signifcantly higher mean anti-HPV-16 (0.618 vs. 0.145), anti-HPV-18 (0.323 vs. 0.309), and anti-HPV-6 (1.371 vs. 0.981) antibody levels were measured, compared to unvaccinated girls (all p<0.05). A correlation between optical density and antibody activity indicated assay sensitivity to increasing levels of antibody activity. Conclusion: We have successfully optimized and implemented a robust and sensitive assay for the evaluation of antibody responses among immunized adolescent girls for monitoring future large-scale HPV vaccination studies in low-income settings. Our results demonstrated greater immunoglobulin G antibody activity within serum drawn from adolescent girls immunized 36 months prior.

Source: KNUST
Optimization of conditions for pectinase production by Saccharomyces cerevisiae ATTC 52712 in solid state fermentation (SSF) and evaluation of its efficacy in orange juice extraction

Pectinases are the group of enzymes which degrade pectin and are one of the most used enzymes in food industry. In fruit juice industry, pectinases are often used to enhance juice extraction. This study sought to optimize conditions for pectinase production from Saccharomyces cerevisiae ATCC 52712 and evaluate its efficacy in orange juice extraction. The study was undertaken in two phases, that is, optimization of conditions during fermentation for the enzyme production and its extraction from the solid medium, and assessing the efficacy of the enzyme produced in juice extraction. The optimal conditions investigated in first stage were fermentation time, proportion of corn cobs and orange peels, pH, temperature and inoculum size during the fermentation period for enzyme production, agitation time during enzyme extraction and the best extraction solvent for enzyme recovery. In the second stage, the crude enzyme was concentrated by ammonium sulphate precipitation and used to study the best reaction time and enzyme dosage required for optimal juice extraction. The optimal conditions obtained in the first stage were 6 days of fermentation, 80:20 % for corn cobs to orange peels, pH of 4 at 30 oC, 10.46 x 106 cells/ml, 30 minutes agitation during enzyme extraction and 0.1 M NaCl as best extraction solvent. The optimal conditions obtained with respect to assessment of the efficacy of the enzyme produced with 60 % (NH4)2SO4 saturation of the crude enzyme solution resulted in 45 minutes reaction/holding time and an enzyme dosage of 40 mg total protein per 200 g of orange mash (0.02 %). Significant increase (p<0.05) in activity was obtained when the crude enzyme produced was saturated to 60 % (NH4)2SO4 concentration. During juice extraction, an enzyme dosage of 10 mg total protein per 200 g of orange mash resulted in 15 % increase in free-run juice while 40 mg total protein per 200 g of orange mash enzyme dosage gave an increase of 123.4 % juice extracted over control. This study showed that the activity of pectolytic enzymes from S. cerevisiae produced under optimal conditions enhanced orange juice extraction significantly thereby making the technology useful in improving orange juice production.

Source: KNUST
Optimization of dilute acid and dilute base pretreatment of tropical sawmill dust for bioethanol production

There is abundance of lignocellulose biomass in Ghana. Currently, there are a lot of sawmill factories and carpentry shops in the country. The use of sawmill dust for the production of bioethanol will go a long way to alleviate environmental pollution by the reduction in the mission of harmful gases which result by burning of these waste products. Most of these gases lead to air pollution and can also contribute to the greenhouse effect. Using sawmill dust will also help minimize the use of land and foodstuffs for the generation of bio-energy. In this study, the optimum amount of glucose was determined by using different concentrations of dilute acids and bases for the pretreatment of different sawmill dust from two different plant species to release glucose for bioethanol production. Concentrations of 0.25 M, 0.5 M and 1 M each of sodium hydroxide, ammonia, sulphuric acid and hydrochloric acid were used for the pretreatment of sawmill dust from Mahogany (Swietina macrophylla) and Kapok (Ceiba pentandra) plant species at different temperatures and resident times. The temperatures used for the sodium hydroxide and ammonia were 75°C, 90°C and 100°C at resident times of 30, 60 and 90 minutes and 121°C at resident times of 10, 15 and 20 minutes. The temperature used for both the sulphuric acid and hydrochloric acid was 121°C at resident times of 30, 60 and 90 minutes. The optimum amount of glucose (3.37 g/l) for the base was achieved by the use of 1 M sodium hydroxide at 100°C for 90 minutes with Ceiba pentandra. The optimum amount of glucose (0.74 g/l) for the acid was attained by the use of 1 M hydrochloric acid at 121°C for 30 minutes with Mahogany plant species. The optimum amount of glucose (5.27 g/l) was attained by the use of cellulase enzyme at 55°C for 30 minutes with Mahogany plant species. The highest amount of ethanol (3.48 x 10-2 % w/v) was attained by carrying out fermentation with Saccharomyces cerevisiae at a temperature of 50°C at a pH of 4.0 for 5 days. The use of high temperatures and concentrations produced higher glucose concentrations with the chemical pretreatments and hence provide an alternative way of producing bioethanol.

Source: KNUST
Optimization of Enzyme-Assisted Hydrothermal Extraction of Shea Butter from Traditionally Pre-Treated Shea Kernels

Enzymes can be simultaneously used to selectively release targeted fats from pretreated Shea nut kernels and improve extraction efficiency at optimized conditions. Three different pre-treated Shea nut substrates: raw kernels, roasted kernels and Shea nut paste from roasted kernels were subjected to treatment with three different industrial enzymes: lipases, pectinases and cellulases, separately and in combination, for Shea butter extraction. The process for enzyme mixtures was optimized at pH of 6, 3 % Enzyme-Substrate concentration, 2 hour hydrolysis time at a temperature of 60 ºC. The results showed that Shea nut paste yielding 48 % fat with pectinases (P), 52% with lipases (L) and 46% with cellulases (C). The amount of percentage fat increased to 52, 54 and 56 at 1:1 P+C, L+C and P+L enzyme combinations respectively. The highest extraction efficiency of 69.96% was recovered from 1:1:1 combination of all three industrial enzymes. The free fatty acids and the peroxide value of the Shea butter recovered ranged from 1.6 ± 0.5 – 2.7 ± 0.1 mgKOH/kg and 3.6 ± 0.6 – 5.4 ± 0.2 mEq/kg respectively. Thus enzyme assisted aqueous hydrolysis of Shea nut biomass for Shea butter production is a promising technology capable of eliminating the drudgery with the mechanical extraction, the safety concerns with the chemical methods and the arduous and cumbersome nature of the traditional village extraction methods. To make this process financially practical, further work is suggested to minimize cost with applications of modified mixes of crude enzymes.

Source: KNUST