ghanaopendata/ghanaian-research-english huggingface dataset:
Drying of onions and shallots and production of value - added products in form of onion / shallot powders and cubes

Prospects for Onion and Shallot powders and cubes production were examined. The Onion / Shallots were sliced, solar dried in a solar tent dryer, milled into powder and molded into cubes. It was observed that Shallot was more nutritious than an equal weight or size of Onion. Onion and Shallot powders (5% moisture level) treated with 1% calcium stearate (anticakiig agent) stayed on the shelf under normal room temperature conditions, for five months with good sensory properties. Onion and Shallot cubes formulated with the composition of 94.5% Onion / Shallot powder, 2% corn starch (binding agent), 1% calcium stearate (anticaking agent) and 2.5% monosodium glutamate (flavour enhancer), had good sensory properties and stayed on the shelf for five months under normal room temperature conditions.

Source: KNUST
Drying Characteristics Of Pretreated Pulp of Triploid and Tetraploid Plantain Varieties

The influence of blanching, citric acid and sodium metabisulphite pretreatment, and temperature on the air drying characteristics and selected functional properties such as water binding capacity, solubility, swelling power, bulk density, pH and rehydration ratio of French Horn, False Horn and FHIA-21 were investigated. Air temperature had the greatest influence on the drying rate as increase in temperature from 50oC to 80oC resulted in an increase in drying rate. The effect of sodium meta bisulphite and citric acid pretreatments increased as the drying temperature decreased and this was evident as citric acid and sodium meta bisulphite in the three plantain varieties at 50oC saved 33% and 25% of drying time respectively for French Horn, 16% and 6.5% for False horn, and 37.5% and 31% for FHIA-21. Meanwhile blanching pretreatment slowed the drying process among all three varieties. Drying occurred in the falling rate period. Two thin layer drying models namely Logarithmic and Page model were evaluated by fitting to experimental moisture ratio data. The Page model satisfactorily described the drying behaviour for the three plantain varieties. Effective moisture diffusivity increased with increasing in drying air temperature. Temperature dependency of moisture on diffusivity was illustrated by the Arrhenius relationship. Over the range of temperature, effective moisture diffusivity varied from 7.54 x 10-10 to 2.37 x 10-9, 5.17 x 10-10 to 3.11 x 10-9 , 3.98 x 10-9 to 5.40 x 10-10 for French Horn, False Horn and FHIA-21 respectively. Activation energy for drying ranged from 11.88 to 33.10, 26.76 to 44.50, 27.24 to 56.61kJ/mol for French Horn, False Horn and FHIA-21 respectively. The effect of variety and pretreatment were significant (p<0.05) on activation energy. Comparison of the proximate analysis of the three varieties indicated marked variations in the nutritional status of the three plantain varieties. The results of the study further indicated that temperature and pretreatment significantly (p<0.05) affected solubility, swelling power, water binding capacity and pH.

Source: KNUST
Durability of Locally-Produced Burnt Clay Bricks

Sustainable economic growth for every country and Ghana for that matter is dependent on infrastructural development, public development projects and the provision of affordable houses for the average populace. Ghana faces a huge housing deficit with its attendant environmental and health problems. Construction is costly due to importation of clinker for cement production. The use of locally-produced burnt clay bricks is an alternative. However, locally-produced burnt clay bricks are perceived not to be durable and of varying properties. Hence, the study investigated the durability of locally-produced burnt clay bricks. Properties of laboratory-produced burnt bricks from Mfensi, Mankranso and Nyamebekyre clays were compared with burnt bricks available on the market but produced from the same clay source. Burnt bricks produced in the laboratory were fired at 800, 900 and 1050oC to investigate the effect of firing temperature on brick durability. Burnt bricks were subjected to salt attack tests and durability assessed by measuring degradation in some physical and mechanical properties. Salt environments considered included sea water, 0.5 M NaCl and 0.5 M Na2SO4. The results show that burnt bricks fired at high temperatures are more durable and have better chances of survival in aggressive environments than bricks fired at low temperatures. Mfensi bricks fired at 1050oC had higher cold crushing strength in seawater and Na2SO4 but not in NaCl. Likewise Mankranso and Nyamebekyre bricks fired at 1050oC also performed very well in seawater and NaCl reducing in strength when exposed to Na2SO4. The differences in durability in the environments studied are due to variation in the chemical composition of the clays which resulted in different properties of burnt bricks. Careful control of clay composition and firing temperature can produce durable burnt clay bricks with high durability, that remain unaltered in the process of their service life even in aggressive environments.

Source: KNUST
The dynamic cone penetrometer as a validation tool for compaction of crushed rock base

The traditional method of verifying the level of compaction achieved on construction sites using sand replacement method is very time consuming and sometimes difficult to perform. Furthermore, on sites open to traffic the safety of the inspectors while conducting sand cone testing on a construction site can be a concern. Therefore, the objective of this study is to ascertain the extent to which the DCP can be used as a tool to verify the level of compaction achieved in-situ on a crushed rock base. Studies were conducted on an on-going road project to ascertain the extent to which the Dynamic Cone Penetrometer (DCP) can be applied in compaction verification on crushed rock. Compaction studies were conducted on three sections of the project site using a 17 ton vibratory roller. DCP test was conducted alongside sand replacement test to determine the level of compaction for one, two, four and eight roller passes. A linear relation was developed between the level of compaction and DPI values from the DCP test which is of form Log (LC) = a - p* log (DPI), where LC is level of compaction by the sand replacement method and DPI is the penetration rate of the DCP. The values of a and p were found to 2.134 and 0.109 respectively. A further study was also conducted in the laboratory to adjust the DPI values at various water content to constant water content. Three levels of compaction were calibrated and the result relation is linear and is of the form DPI= K + tav, K is a constant that depends on the level of compaction and w is the water content of the material at time of testing. LC=93% CR-B10: DPI = 3.874 + 0.855w LC-97% CR-B25: DPI = 1.228 + 0.836w LC=101% CR-B55: DPI = 1.316 + 0.470w

Source: KNUST
Dynamic Bandwith Utitlization in Software Defined-Based Campus Networks

The efficient utilization of bandwidth in campus networks is a major traffic engineering issue. It requires a complete knowledge of the underlying physical network architecture as well a means to automate or reactively and proactively program the network. The static nature of traditional network creates a hurdle that must be overcome to achieve the above. The Software Defined Network architecture proposes a novel way to automate, program and dynamically configure computer networks. This work uses the VMware virtualization software and the GNS3 network emulator to convert a traditional campus network into a Software Defined-based campus network. A data plane made up of software-based replicas of network devices is designed and configured to connect to a controller software. A network application scheme is implemented by leveraging the Hierarchical Token Bucket Queuing Discipline which automatically programs bandwidth allocation at the data plane through the controller based on traffic demands. The functionality of the architecture is tested by carrying out a number of parallel-connections to simulate changing traffic patterns. This is done using the Iperf Application. The results show the conversion of a traditional campus network into a Software Defined-based campus network. It also depicts the complete emulation of the entire Software Defined-based campus network. At the data plane of the emulated network, devices are able to forward packets to one another with the most active port forwarding about 9,000 packets. The controller obtains a global of all 11-network devices in the emulated network. The latency between the controller and the software defined switches at the data plane ranges between 50 and 62.5 milliseconds. The throughput between the controller and the software defined switches at the plane ranges between 2 and 9 Mbps. Application Plane to Control Plane communication in the emulated network is executed in an average of 30 milliseconds and bandwidth utilization occurs in a minimum of 11seconds and peaks at 27.5 seconds. It however becomes steady at 17 seconds as traffic patterns vary

Source: KNUST
Dynamic Programming Based Bus Replacement Policy For Metro-Mass Transit Limited-Kumasi Depot

Recent advances in automobile replacement have made possible the deployment of several strategies aimed at minimising the total operational cost on one hand and maximising the total net profit on the other hand of an equipment in service of a given organization. This thesis looks at the various operational costs associated with running an automobile bus as a background to making a future replace or keep decision throughout a given planned horizon. Our work focuses on using dynamic programming in solving the backward profit recursive relation for an optimal replacement policy via Microsoft Excel solver implementation. This approach finds the optimal replacement policies to be replaced in every five and four years of the bus’s service life: Verband Deutscher Lokomotivindustrie (VDL) Commuter, Verband Deutscher Lokomotivindustrie (VDL) Neoplan City (2nd generation), Verband Deutscher Lokomotivindustrie (VDL) Daf and Verband Deutscher Lokomotivindustrie (VDL)Jonckheere buses should be replaced every five (5) years with Neoplan City (1st generation) bus replaced every four (4) years.

Source: KNUST
Dynamic linear state space model for forecasting peak and short-term electricity demand using kalman filtered monte carlo method

Electricity has become a major part of human life, especially in our part of the world. It is one of the most used energy across the world. Due to the fast changing world, the demand for electricity keeps on increasing from time to time yet there is not any efficient way of storing this energy for future use. So operators are very cautious about the amount to release and also to meet the demand of their consumers. For this reason, load forecasting has become a main integrated section in energy manage ment and production. This research seeks to look at Short-Term Load Forecasting. The objective is to forecast the peak demand and total energy generated or elec tricity demand. So the Seemingly Unrelated Time Series Equations Model which models the level or state and trend in the system was used for the study. A Markov Chain Monte Carlo (MCMC) method, Gibbs Sampler, together with the Kalman Filter and Kalman Smoother, the Forward Filtering Backward Sampling with Gibbs Sampler Algorithm were applied to the model to simulate for the variances also to predict the peak demand the next day’s peak and electricity demand. The running ergodic mean showed the convergence of the MCMC process and hence the posterior means of the variances were estimated. The one-step-ahead forecast showed a Mean Absolute Percentage error (MAPE) of 3.696% error in the peak demand forecast and a 4.235% error in the electricity demand forecast. The forecast for the next day was about 2187MW and 44090MW for the peak and electricity demands respectively. For further studies, the model can be extended to capture seasonal components.

Source: KNUST
Dynamics and control of poultry diseases in Ashanti Region

The thesis deals with five important diseases in poultry namely. Coccidiosis, New castle. Helminthiasis, Gumboro and Bacterial diseases. The objective is to find out whether rainfall and temperature have any effect on these diseases so that plans can be made to control these diseases. A brief description of each the diseases are given. Time series models, in particular, autoregressive models were used to identify models for the various diseases. It was found out that the correlations of Newcastle diseases with temperature and total rainfall were not significant. However, with the univariate analysis, Newcastle disease turned out to be an autoregressive model of order one: AR(1). Coccidiosis also turned out to be an autoregressive model of order one: AR( 1). Bacterial disease had an autoregressive model of order two; AR(2). Gumboro disease also an autoregressive model of order two; AR(2). Coccidiosis had an autoregressive exogenous model of order two, ARX(2) with minimum temperature. The correlation of Gumboro and total rainfall was significant. Gumboro and total rainfall came out to have autoregressive exogenous model of order two, ARX(2). Gumboro also had an autoregressive exogenous model of order two, ARX(2) with minimum temperature. Helminthiasis and Bacterial diseases correlated best with average temperature. The autoregressive exogenous model for mortality in Helminthiasis versus maximum temperature was of order two, ARX(2). Bacterial diseases mortality versus maximum temperature was an autoregressive exogenous model of order two. ARX(2). Protein is a very important nutrient in the diet of humans. Poultry meat is a source of animal protein. Poultry diseases have been claiming the lives of birds. This situation obviously reduces the amount of animal protein poultry farmers could have produced for human consumption. This thesis has identified the models of these important poultry diseases in Ashanti region. In conclusion it is hoped that the models will alert farmers to know when to take precautions to avoid the occurrences of outbreaks.

Source: KNUST
Dynamical system theory application to earth- satellite pitch attitude librations

We have developed in this thesis, an analytical methodology for solving a differential equation model representing Pitch Attitude librations of an Earth —Satellite. This highly non linear equation of motion of the Pitch Attitude librations is transformed into a system of equations in terms of the anomaly. The system of equations is linearized about the origin and then analyzed in the context of Dynamical System Theory for its equilibrium configuration and periodicity. We obtain the non linear system by augmenting the level of non linearity of the linearized system through the addition of non linear terms. In our analytical approach, first, the linearized system is solved using the Floquet theory which is based on the periodicity of the coefficient matrix. Then, the complete non linear solution is obtained by a successive approximation scheme involving the fundamental matrix. This methodology is used to analyze our sample problem, a specific satellite configuration that has been studied in a previous investigation using numerical integration techniques. Our results show remarkable agreement both qualitatively and quantitatively with published data obtained from the numerical integration techniques.

Source: KNUST
Dynamics of Christian Education from the Ghanaian Perspective: A Study of the Christian Education Ministry of Some Selected Churches in the Kumasi Metropolis

The gap between Christian profession and Christian practice among many African Christians is probably because Christian education lags much behind Christian theology in Africa. Much work has been done by some practical Christian theologians to look at the subject of Christian education, especially in the European and American contexts, but relatively little work has been done on Christian education in Ghana. There is therefore little theoretical framework for Christian Education in Africa. As a result, much of the Christian educational formulations in relation to the local church in Ghana are not being effectively communicated to the church’s educational facilitators. This study is an attempt to describe and evaluate the Christian educational ministries of the local churches in the Ghanaian ecclesiastical context for effective communication of the Christian faith for relevant educational impacts. Dynamics of effective teaching and learning are described in terms agreeable to the abundant literature on Christian education. At the end, some recommendations are made for a possible formulation of a contextualized theology of Christian education suitable for the Africa context.

Source: KNUST
Dynamics of human-bat interactions: implications for potential transmission of coronavirus infection in Kwamang, Forikrom and Buoyem rural communities in Ghana

Evidence of Coronavirus in two species of cave dwelling insectivorous bats: Hipposideros aff. ruber and Nycteris cf. gambiensis has been confirmed in Ghana. This raises questions about human health risks since it is unknown whether this virus would potentially cause a zoonotic disease in humans. Human interactions, including livelihood practices that bring people into contact with cave bats are poorly documented. The study had a social survey design. Data was collected using focus group discussions; direct observations; face-to-face interviews with structured questionnaires and a review of available published/unpublished documents. A total of 1274 respondents were interviewed; Buoyem (412), Forikrom (362) and Kwamang (500) from July 2011 to October 2012. The results highlight the existence of human associations with bats, which have the potential to spread zoonotic diseases through complex contact networks. Sources of human-contact with bats identified include caves, farms, homes and schools. Caves were the highest source of contact with bats representing 31%, 45% and 37% in the three communities respectively. Age and gender were major factors that influenced contact with bats at the sources. Community use of bat caves were recreation, religious activities, bat hunting, water fetching, and guano collection. Occurrence of bat exposures included consumption of bat meat, mode of bat hunting and bat bites. Bat consumption was highest among respondents older than 50 years in all the communities representing 95%, 58% and 54% for Buoyem, Forikrom and Kwamang respectively. In Forikrom and Kwamang, men consumed more bat meat than women. Common tools for hunting bats within all three communities were guns, catapult, sticks and hands. Bat bites were highest in Buoyem (24%) followed by Forikrom (2%) and Kwamang (2%). More men than women experienced bat bites at Buoyem and Kwamang. Older respondents and men were the most at risk of bat exposures in all three communities. The study found no association between visiting bat caves and common cold infections. Furthermore, there was no report of any respiratory infections or epidemics from bat bites and bat consumption. As the human-bat interface is essential to the process of potential zoonoses like Coronavirus infection, one of the most important strategies for early detection would be monitoring people who have high exposure to bats. Public education to promote behavioural changes of humans would also enhance the prevention of any potential zoonotic diseases from bats.

Source: KNUST
Dynamics of Land Use Planning And its Effects On Socio-Economic Development. Case Study of Sunyani Municipality and Odumasi in the Brong Ahafo Region

The general objective of the study was to assess how land-use planning can be effectively used to enhance socio-economic development in the Sunyani Municipality and Odumasi. It is based on the aforementioned that this research was designed to identify some of the inherent problems associated with land use planning and how it has impacted on socio-economic development in both Sunyani Municipal and Sunyani West District Assemblies in the Brong Ahafo Region of Ghana. Sunyani Municipality has several layouts but for the purpose of this study the sectors 2, 3 and 4 were purposely selected as these areas are high class residential and well planned communities in the Sunyani Municipality. In Odumasi sector 9 was purposely selected. All these sectors gave a total of 3516 (Sunyani, 3116 and Odumasi, 400). 84 landlords were interviewed in Sunuyani Municipality and 40 landlords were interviewed in Odumasi. . The study indicated that all the landlords interviewed had an approved site plan which was prepared from a planning scheme. The nature of land ownership can delay land use planning process as there are some cases of litigation over who owns land and has the right to sell land. The Assemblies could not effectively control physical developments as they were constrained by inadequate logistics and personnel. 55 percent of landlords in Odumasi did not have building permits. In response to these findings this recommendation among others were made: The District/Municipal Assembly in the study area should resource the Development Control Unit in terms of logistics to effectively monitor all forms of physical development.

Source: KNUST
The Dynamics of Klein-Gordon Equation for a Slow Varying Interacting Wave Field

The main purpose of the study was to investigate the outcomes when an interacting term is incorporated into a Klein-Gordon equation, in particular when the interacting term involves a slow periodic wave field. The study further seeks to investigate in the context of Dirac approach to the quantum relativistic free particle. A slow varying periodic field was considered in the study as a potential field which interacted with quantum mechanics wave particle field as in the Schrodinger equation for a forced particle. In the relativistic context of the study, the Klein-Gordon equation was considered as a homogenous differential equation which represented a free particle and the interacting term was placed on the right hand side, having a “slow varying potential” field as a factor. It was found that for the zeroth order approximation of the slow varying wave field, Klein-Gordon equation still remained as field but there was only a shift in the energy mass. However, with the second order approximation, a formal Quantum Harmonic Oscillator was obtained. This yielded discrete positive and negative energy mass, suggesting particle and antiparticle states. An equivalent Dirac formalism which also incorporated an interacting term was obtained, with a recovery of particle and antiparticle states by means of creation and annihilation operators.

Source: KNUST