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- ItemValorisation of selected Ghanaian seaweeds for biogas production(KNUST, 2018-04) Opoku, GertrudeABSTRACT Seaweed biomass has been considered as a promising feedstock for biogas production because it contains high concentrations of biodegradable organic solids. The research aimed at producing biogas from seaweeds. In order to optimize the biogas yields of seaweeds, batch fermentation test was conducted to examine the effects of total solids load and inoculum type on methane content from brown seaweed Sargassum vulgare and green seaweed Ulva fasciata before biogas production of seaweeds were conducted. From the results obtained, the highest methane concentration for brown seaweed and green seaweed were 55.45% v/v and 60.6% v/v using rumen and large intestine contents from cattle respectively. 8% TS (Total solids) of green seaweed inoculated with large intestine contents yielded the highest methane gas (60.6%) whiles 10% TS of brown seaweed inoculated with rumen contents recorded the highest methane gas (55.45%) over a digestion period of 55 days. The 8% TS of green seaweed also gave the highest biogas and methane yields of 608.7 ± 37.84 ml/g VS and 218.22 ± 15.38 ml CH4/g VS respectively whiles 10% TS of brown seaweed gave lower biogas and methane yields of 308.48 ± 4.09 ml/g VS and 106 ± 2.4 ml CH4/g VS respectively compared to green seaweed. However, the biogas and methane yields of green seaweed were both inhibited at 10% TS whiles those of brown seaweed were both inhibited at 12% TS. From the results obtained in this study, both seaweed species have high potential as substrates for biogas production in Ghana.
- ItemProduction of wine from synsepalum dulcificum (miracle berry).(KNUST, 2015-08) Aduboffour, Stephen KwakuRed wine was produced from Synsepalumdulcificum (Miracle Berry) extract. The effects of varying pH and Inoculum levels during fermentation on wine parameters like change in soluble solids, pH, titratable acidity, acid taste index, antioxidant activity and polyphenol concentrations were investigated. During fermentation, changes in brix and pH were monitored. There was a decrease in brix, pH, phenolic content and antioxidant activity for all samples fermented at varying pH after fermentation. There was, however, an increase in titratable acidity and acid taste index after fermentation. Wine sample fermented at pH 3.8 using 1% inoculum (Wine A), wine sample fermented at pH 4.6 using 1% inoculum (Wine B) and wine sample fermented at pH 5.8 using 1% inoculum (Wine C) produced 13%, 10% and 10% (v/v) alcohol, respectively. With respect to varying Inoculum, there was a decrease in brix, pH, phenolic content and antioxidant activity for wine sample fermented at pH 4.6 using 1% inoculum (Wine E) and wine sample fermented at pH 4.6 using 2% inoculum (Wine F). Wine E and F also recorded an increase in titratable acidity and acid taste index after fermentation. At the end of the fermentation process, wine sample E and Fhad alcohol content of 10% and 12% (v/v) respectively. The study revealed that it is possible to produce red wine from miracle berry and its qualities can be manipulated by controlling the pH and inoculum levels.
- ItemImplementation of adaptive neuro fuzzy inference system for malaria diagnosis. (A case study at Kwesimintsim Polyclinic).(KNUST, 2015-09) Appiah, RichardHealth issues have become one of the problems bedeviling most developing and underdeveloped countries in our world today. Ghana is of no exception from this menace especially in Africa. One of the prevalent diseases battling with Ghanaians and Africa as a whole is the malaria disease. In 1994, the WHO reported that malaria and measles were the most common causes of premature death. in children under five(5) years. Diagnosis of malaria in many cases has not been accurate by most doctors or physicians due to external human factors such as fatigue and hastiness among others, thereby leading to patients being subjected to treatment again which also come with cost. Hence the need for this research work entitled, “Implementation Of Adaptive Neuro Fuzzy Inference System For Malaria Diagnosis. (A Case Study At Kwesimintsim Polyclinic) This paper employs the use of Adaptive Neuro Fuzzy Inference System (ANFIS) to provide a better option for malaria diagnosis than the traditional diagnosis method which is characterized by erotic guess work and observation of patients by doctors. ANFIS, which is derived from the term Adaptive Network Fuzzy Inference System, was first proposed by Jyh-Shing and Jang and later changed to Adaptive Neural Fuzzy Inference System. This system is designed to allow IF THEN rules and membership functions (fuzzy logic) to be constructed based on the historical data and also includes the adaptive nature for automatic tuning of the membership functions. Related works done by various authours in the area of study were reviewed. One hundred(100) datasets of patients from the clinic were used in this research work. Sixty(60) of the datasets were used as training datasets for training the ANFIS and forty(40) datasets were used checking datasets. The results tested after training showed that ANFIS has the ability to diagnose malaria efficiently than the traditional method with very minimal error.
- ItemModeling lapse rates with economic variables: The vector autoregressive model approach(KNUST, 2016-04) Aryeh ,IsaacAbstract Life insurance contracts are accompanied by risks. This study focuses on the risk involving termination of life policies by the policyholders. This study seeks to identify the main determinants of lapse rates in the Ghanaian life insurance industry. The data available span from 2006 to 2014 and were recorded on monthly basis. Literature research on predictive modeling of lapse rates in the insurance industry led to the choice for predicting with a VAR Model. A total of ve (5) variables were analyzed on their relationship with the average lapse rate. Of these variables in ation, stock market return and interest rate proved valuable for modeling. The vector auto-regression (VAR) model was used to capture the evolution and the interdependencies between the variables. All the variables in the VAR were treated symmetrically by including for each variable an equation explaining its evolution based on its own lags and the lags of all the other variables in the model. The main limitation of this research was the small amount of data and their level of detail. Since the results of this research are promising it is recommended to extend the research to other parts of the country. To increase the statistical strength and accuracy of the inferences that can be made it is also recommended to examine the lapse rates at a policyholder level.
- ItemAn enhanced ECC for securing data, comparative study.(KNUST, 2017-12) Boahen, Edward KwadwoABSTRACT The purpose of this research is to enhance a cryptographic system called the Elliptic Curve Cryptographic System. Elliptic Curve cryptosystem is a technique of public-key encryption which is rooted on the arithmetical construction of elliptic curves over finite fields. Elliptic Curve Cryptographic System necessitates smaller keys compared to non-ECC cryptography to offer equal security. Elliptic curves are valid for digital signatures, key agreement, generators, pseudo-random and other related tasks. The first phase of the project involves understanding the key exchanges of Diffie-Hellman and also applying the properties of the Elliptic Curves, and it is terminated with key facts that the Elliptic Curve Cryptography has a shorter key length, saves bandwidth which facilitates key generation during the encryption/decryption of data, also the assurance of faster encryption and decryption, and notwithstanding its efficiency and efficacy in small devices.