Faculty of Engineering, Technology, Applied Design & FineArt (FETADFA)
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Item Open Access Antistripping potential of cement kiln dust on recycled asphalt pavement. Innovative Infrastructure Solutions(Springer Nature., 2025) Usman, Kabiru Rogo; Ali, Atheer Muhammed; Wakawa, Yakubu Mamman; Usman, AbbasCement kiln dust (CKD) is the by-product of cement manufacturing. It is collected using air pollution control devices (APCDs) also known as electrostatic precipitators in the form of fue dust to minimize environmental hazards. This study investigates the potential use of CKD as a fller material and its novel antistripping properties on recycled asphalt pavement (RAP). CKD's chemical properties, make it desirable for improving stripping resistance of asphalt in areas prone to high rainfall or moisture exposure, but its application in RAP remains a grey area to explore. Its dual role in improving both adhesion and mechanical properties of asphalt makes it particularly advantageous, in terms of sustainability, cost and resource efciency. The rising production cost, environmental safety concerns, and the push towards sustainable consumption/ production seek alternatives for traditional antistripping agents for asphalt production, thus, CKD. This study prepared densegraded asphalt concrete with nominal maximum aggregate size (NMAS) of 14 mm with 1%, 3%, and 5% of CKD by weight of RAP according to Malaysian standard. A total of fve (5) asphalt concrete (AC14) mixtures were produced with an optimal 3% CKD used in the modifed mixtures at the optimum binder content (OBC). The antistripping properties of CKD in hot mix asphalt (HMA) were assessed through indirect tensile strength test (ITS), indirect tensile stifness modulus (ITSM) and boiling tests on the asphalt mixtures. In addition to the physical, mechanical, chemical, and structural/morphological tests, the safe inclusion of CKD in terms of heavy metals was evaluated by applying toxicity characteristic leaching procedure (TCLP) test. The fndings confrm that CKD meets ASTM C150 standards for type II and type IIA hydraulic cement for use as a fller in asphalt. The fatigue cracking resistance, antistripping resistance in terms of the tensile strength ratio (TSR) & indirect tensile stifness modulus (ITSM) tests indicated that CKD modifed RAP mixes performed better than the control (CNTRL), RAP only and CKD modifed RAP mixes. It also compares favourably with CNTRL+CKD mixture. Ultimately, the boiling test results indicated that CKD blended RAP mix surpassed the minimum 80% TSR for moisture damage resistance.Item Open Access A state-of-the-art review on the modeling and probabilistic approaches to analysis of power systems integrated with distributed energy resources.(Ain Shams Engineering Journal, 2024) Wanjoli, Paul; Abbasya, Nabil H.; Moustafa, Mohamed M. ZakariaModern power systems are shifting toward decarbonization and incorporation of distributed energy resources (DERs) to replace fossil fuel generators. Although promising, DERs introduce uncertainty because of their intermittent nature. This study provides a comprehensive survey of current approaches for modeling system uncertainties and methods of analysis, particularly in the context of static voltage stability studies within modern power systems. Emphasis is placed on evaluating various models applied to different system random variables (RVs), focusing on their suitability for those particular RVs. Additionally, the study examines the characteristics and frameworks of prominent probabilistic methods (PM), evaluates their efficacy, and discusses static voltage stability analysis approaches, emphasizing solution structures and appropriate applications. It concludes by thoroughly reviewing both numerical and analytical PM methods and offering insights into their strengths and limitations. The provided comprehensive survey reveals that, considering system uncertainties, voltage stability studies have gained the most share, followed by small-signal stability studies, whereas the frequency stability studies have gained the least share.Item Open Access A new combined analytical–numerical probabilistic method for assessing the impact of DERs on the voltage stability of bulk power systems(Energy reports, 2024) Wanjoli, Paul; Moustafa, Mohamed M. Zakaria; Abbasy, Nabil H.The integration of distributed energy resources (DERs) and unpredictable loads has increased uncertainty in power systems. Traditional methods struggle to assess performance under these uncertainties, and existing probabilistic methods face challenges with complexity and accuracy. This paper introduces a new combined analytical–numerical probabilistic method to assess the impact of DERs on voltage stability. Using Bayesian Parameter Estimation (BPE), the method derives the analytical properties of random variables (RVs) associated with DERs and loads, obtaining posterior distributions. The Metropolis–Hastings sampling technique then estimates these posteriors numerically, enabling accurate predictions of DERs and load outputs. Voltage stability analysis was performed using the continuation power flow method and validated on the IEEE 59- bus test system in MATLAB/Simulink. The results show that integrating DERs significantly improves voltage stability. The proposed method outperforms the Monte Carlo simulation (MCS)-based method in accuracy and computational speed, increasing DERs penetration and voltage stability limits by 3%. It closely matches MCS voltage estimates but requires fewer iterations (500 per loading increment) compared to MCS’s 1000, leading to faster computation times (a few hours to one day versus up to three days for MCS). This method provides an efficient solution for managing uncertainties in power systems.Item Open Access Probabilistic Power Flow Analysis of DERs Integrated Power System From a Bayesian Parameter Estimation Perspective(IEEE Access, 2024-11) Wanjoli, Paul; Moustafa, Mohamed M.Zakaria; Abbasy, Nabil H.The rise of distributed energy resources (DERs) in power systems demands efficient models for power flow analysis. Existing models often face challenges in balancing computation speed and accuracy. This paper presents a probabilistic power flow (PPF) method for systems with DERs, using Bayesian parameter estimation (BPE) to handle uncertainties in wind speed, solar irradiance, and loads. By applying Bayes’ theorem, BPE estimates posterior distributions, refined by the Metropolis-Hastings algorithm. Validated on IEEE 39-bus and 59-bus test systems in MATLAB/Simulink, BPE outperformed the 2m+1 point estimate method (PEM) in terms of accuracy, computation speed and scalability. Simulation results demonstrate superior accuracy of BPE, yielding voltage profiles and congestion indices closely matching those of Monte Carlo Simulation (MCS) but with lower computation time. For instance, under heavy loading, BPE achieved a congestion index of 0.0617 (compared to PEM’s 0.2228 and MCS’s 0.0611). BPE also provided faster results as system size increased, averaging 3.477 hours, versus PEM’s 6.837 hours and MCS’s 11.524 hours. Statistical analyses confirmed BPE’s consistent performance and minimal error, making it more efficient for large systems. Thus, BPE-based PPF is recommended for power system planning and operation under uncertain conditions, owing to its robustness, accuracy, and computational efficiency.Item Open Access Determining Bandgap of Thermochromic Phosphor Films via Reflectance Measurements under Controlled Heating.(Kabale University, 2024) Rwabona, Katashaya StevenIn this article, we present a method to determine the bandgap of a thermochromic phosphor film by simple reflectance measurements under controlled heating. The phosphor is illuminated by a light-emitting diode while being heated continuously. The reflected light is detected using a calibrated photodiode circuit based on an operational transconductance amplifier. We apply the Schuster- Kubelka-Munk function to deduce the absorbance over temperature and thus the bandgap. We show, for the first time, that the thermochromic phosphor's colour change follows Arrhenius's Law and therefore involves activation energy. We estimate the bandgap to be between 1.1 eV and 1.9 eV and find an activation energy of 46.67 ±1.6 kJ/mol. The simplicity of the approach will appeal to undergraduate teachers and students of physics and materials science. The technique can be used to investigate other thermochromic materials as well.Item Open Access The Development Related Role of Pottery Production in the Ankole Region in Western Uganda: A Case Study(Bp International, 2023-02-08) Kayamba, William K.; Kwesiga, PhilipThe main aim was to look at how the pottery business contributes to reducing poverty and unemployment as well as how it affects the environment. The study looked into the socioeconomic and technical aspects of pottery manufacture in the Ankole district of western Uganda. Both qualitative and quantitative techniques of data gathering and analysis were used throughout the study's fieldwork. First, 148 respondents were given questionnaires from a diverse cross section of the Ankole district. Second, in order to get a more thorough grasp of the experiences and viewpoints of both traditional and modern potters— something a questionnaire alone could not provide—40 potters were interviewed and seven focus group talks were held with potters from this region. According to the results, women are predominantly responsible for creating traditional pottery, whereas males are mostly involved in developing new techniques and manufacturing commercial pottery. Unquestionably, brick and tile manufacturing has developed into a successful industry, particularly for male adolescents because to the great demand for the goods from both rural and urban populations. However, pottery-related activities have wreaked havoc on the ecosystem. These efforts have produced pools of still water in some locations, which serve as breeding grounds for mosquitoes that carry malaria over much of the region.Item Open Access Clean eco-friendly cooking energy as sustainable approach and mitigation to climate change: A case study of Ankole, Western Uganda(Kabale University, 2023-02-07) Kayamba William KariitiThe study investigates how communities in the Ankole region, western Uganda are coping with a shortage of cooking fuels, climate change and what strategies they have set up to counteract its effects using innovative, sustainable, renewable and affordable technological methods. The objectives of the study are: 1) to investigate the type of cookstoves used in cooking that is being used in the area under study. 2) To suggest eco-friendly cook stoves that can be used for cooking to save the environment and reduce health hazards that are related to inhalation of smoke. It was carried out in the districts of Mbarara and Bushenyi which are diverse in their setting. The main objective was to investigate how traditional cooking fuels have become a health hazard to many mothers and children in Ankole, human activities and rural-urban migration, have caused hiking of prices for fuel for cooking; wetland drainage, bush clearing for farming, charcoal burning, brick making associated with social and economic developments have affected the environment. Traditional methods of cooking still dominate in Ankole, where three stones are still used. Charcoal has become a major fuel for cooking in many homes as an alternative to firewood, in addition to briquettes, biogas, LPG and volcanic rocks. A sustainable eco-friendly stove is proposed to mitigate environmental degradation.Item Open Access Clean Eco-Friendly Cooking Energy as Sustainable Approach and Mitigation to Climate Change: A Case Study of Ankole, Western Uganda.(Kabale University, 2023) Kayamba, William KariitiThe study investigates how communities in the Ankole region, western Uganda are coping with a shortage of cooking fuels, climate change and what strategies they have set up to counteract its effects using innovative, sustainable, renewable and affordable technological methods. The objectives of the study are: 1) to investigate the type of cookstoves used in cooking that is being used in the area under study. 2) To suggest eco-friendly cook stoves that can be used for cooking to save the environment and reduce health hazards that are related to inhalation of smoke. It was carried out in the districts of Mbarara and Bushenyi which are diverse in their setting. The main objective was to investigate how traditional cooking fuels have become a health hazard to many mothers and children in Ankole, human activities and rural-urban migration, have caused hiking of prices for fuel for cooking; wetland drainage, bush clearing for farming, charcoal burning, brick making associated with social and economic developments have affected the environment. Traditional methods of cooking still dominate in Ankole, where three stones are still used. Charcoal has become a major fuel for cooking in many homes as an alternative to firewood, in addition to briquettes, biogas, LPG and volcanic rocks. A sustainable eco-friendly stove is proposed to mitigate environmental degradation.Item Open Access Concrete Production and Curing with Recycled Wastewater: A Review on the Current State of Knowledge and Practice(Hindawi, 2022-12-10) Tobby Michael, Agwe; Tibenderana, Philip; Twesigye-Omwe, Moses N; Abdulkadir, Sholagberu Taofeeqproperly cited. A number of factors have combined to put excessive pressure on the finite available freshwater resources. These include increasing population, rapid urbanization, industrialization, changed land pattern usage and land cover, change in the overall ecological system, and increased temperature and unscientific compromises in the extraction of water are at alarming threshold putting pressure on the finite available freshwater resources. As a result, many countries have been stressed or are at the verge of being stressed. The problem is worsened day by day by prolonged drought, unchecked discharge of untreated or partially treated wastewater to the freshwater reservoirs and lack of proper water quality control measures and management. Many initiatives such as Zero Liquid Discharge of industrial wastewater into freshwater bodies such as reservoirs, lakes, and ponds, and the use of recycled wastewater for irrigation and domestic purposes have started to be embraced as measures to put a check on the fast-depleting freshwater resources for sustainable socio-economic development. The construction industry is the second largest consumer of freshwater just after agriculture. Concreting alone consumes, annually, over one trillion m3 of freshwater globally while the concept of the use of wastewater and/or recycled water in the concrete-making processes is yet to be adopted. Hence, this paper presents a general review of the current state of knowledge and practice on concrete production and curing using recycled wastewater from industrial, commercial, and domestic activities. An extensive review of the existing literature revealed that recycled water is ft for concrete production and curing purposes. The observations made are based on the assessment of wastewater quality parameters and their impacts on some selected concrete properties such as initial setting time and compressive strength. Due to scanty research on the impacts of varying concentrations of different ingredients in any questionable water on selected properties of reinforced concrete and its durability, thus, further research is recommended.Item Open Access Concrete Production and Curing with Recycled Wastewater: A Review on the Current State of Knowledge and Practice(Hindawi, 2022) Tobby Michael, Agwe; Philip, Tibenderana; Moses N, Twesigye-Omwe; Joel Webster, Mbujje; Abdulkadir, Sholagberu TaofeeqA number of factors have combined to put excessive pressure on the finite available freshwater resources. These include increasing population, rapid urbanization, industrialization, changed land pattern usage and land cover, change in the overall ecological system, and increased temperature and unscientific compromises in the extraction of water are at alarming threshold putting pressure on the finite available freshwater resources. As a result, many countries have been stressed or are at the verge of being stressed. The problem is worsened day by day by prolonged drought, unchecked discharge of untreated or partially treated wastewater to the freshwater reservoirs and lack of proper water quality control measures and management. Many initiatives such as Zero Liquid Discharge of industrial wastewater into freshwater bodies such as reservoirs, lakes, and ponds, and the use of recycled wastewater for irrigation and domestic purposes have started to be embraced as measures to put a check on the fast depleting freshwater resources for sustainable socio-economic development. The construction industry is the second largest consumer of freshwater just after agriculture. Concreting alone consumes, annually, over one trillion m3 of freshwater globally while the concept of the use of wastewater and/or recycled water in the concrete-making processes is yet to be adopted. Hence, this paper presents a general review of the current state of knowledge and practice on concrete production and curing using recycled wastewater from industrial, commercial, and domestic activities. An extensive review of the existing literature revealed that recycled water is fit for concrete production and curing purposes. The observations made are based on the assessment of wastewater quality parameters and their impacts on some selected concrete properties such as initial setting time and compressive strength. Due to scanty research on the impacts of varying concentrations of different ingredients in any questionable water on selected properties of reinforced concrete and its durability, thus, further research is recommended.Item Open Access Concrete Production and Curing with Recycled Wastewater: A Review on the Current State of Knowledge and Practice(Hindawi, 2022) Tobby Michael, Agwe; Philip, Tibenderana; Moses N., Twesigye-Omwe; Joel, Webster Mbujje; Sholagberu Taofeeq, AbdulkadirA number of factors have combined to put excessive pressure on the finite available freshwater resources. These include increasing population, rapid urbanization, industrialization, changed land pattern usage and land cover, change in the overall ecological system, and increased temperature and unscientific compromises in the extraction of water are at alarming threshold putting pressure on the finite available freshwater resources. As a result, many countries have been stressed or are at the verge of being stressed. The problem is worsened day by day by prolonged drought, unchecked discharge of untreated or partially treated wastewater to the freshwater reservoirs and lack of proper water quality control measures and management. Many initiatives such as Zero Liquid Discharge of industrial wastewater into freshwater bodies such as reservoirs, lakes, and ponds, and the use of recycled wastewater for irrigation and domestic purposes have started to be embraced as measures to put a check on the fast depleting freshwater resources for sustainable socio-economic development. The construction industry is the second largest consumer of freshwater just after agriculture. Concreting alone consumes, annually, over one trillion m3 of freshwater globally while the concept of the use of wastewater and/or recycled water in the concrete-making processes is yet to be adopted. Hence, this paper presents a general review of the current state of knowledge and practice on concrete production and curing using recycled wastewater from industrial, commercial, and domestic activities. An extensive review of the existing literature revealed that recycled water is fit for concrete production and curing purposes. The observations made are based on the assessment of wastewater quality parameters and their impacts on some selected concrete properties such as initial setting time and compressive strength. Due to scanty research on the impacts of varying concentrations of different ingredients in any questionable water unselected properties of reinforced concrete and its durability, thus, further research is recommendedItem Open Access Assessment on Power Distribution Network Planning in sub-Saharan Africa(IEEE, 2021) Michael, E. Irechukwu; Michael, N. Irechukwu; Samuel, S. MushakangomaPower system distribution network planning (PSDNP) encompasses several tasks including ensuring sufficient substation capacity and distribution capacity for the end users. Both rural communities and urban dwellers benefit when there is a well-planned distribution network. City power consumers enjoy stable electricity supply and the number of annually connected rural households increases with an efficient planning scheme in place. However, this is not the case in many cities and rural areas in sub-Saharan Africa. Poor distribution network planning by many power utilities has led to the annual energy demand growing at a much higher rate than the number of electrified households in many sub-Saharan African countries. Therefore, this paper discusses challenges faced by power utilities and energy consumers due to poor distribution planning techniques. This paper proposes an implementation plan to address the inefficient planning challenges faced by the rural communities and urban dwellers. After that, a case study is selected in East Africa, and the solutions are applied.Item Open Access Analysis of Leaching Rate of Heavy Metals from Fly Ash at Varying Leachant pH & Cumulative Liquid to Solid Ratios(i-manager’s Journal on Material Science, 2020) Tobby, Micheal Agwe; Sharma, S. N.; Pandey, GovindFly ash (FA) is a particulate matter consisting of finely divided, non-combustible particles obtained from the flue gases arising from combustion of coal, accounts for over 80% of the total ash produced during coal combustion. In 2018 alone, about 780 million tons of FA has been generated globally, of which voluminous quantity remained unutilized, hence dumped into the environment. This continued disposal of FA into the environment makes the heavy metals contained therein to move out in the leachate generated, polluting the soil, surface and ground water sources among others. In this study, 5 sets of leaching test columns were packed with an equal quantity of air dried fly ash samples and each of them leached with leachant of pH 5.87, 6.08, 6.41, 6.46 and 7.01 and eluate from each column collected at cumulative liquid to solid (L/S) ratios in l/kg of 0.1, 0.2, 0.5, 1.0 and 2.0. Analysis of the eluate for Copper (Cu), Selenium (Se), Zinc (Zn), Cadmium (Cd), Lead (Pb), Nickel (Ni), Chromium (Cr) and Arsenic (As), revealed that the concentrations of Se at Selenium L/S of 0.1 for leachant pH of 5.87, 6.41 and 7.01, exceeded the allowable limits for non-hazardous wastes disposal into the landfills.Item Open Access Effect of Boron Content on Strain-Hardening Exponent in Recycled Steel(International Journal of Academic Engineering Research, 2020) Christopher, Senfuka; Paul, KizitoWhile the elastic zone in the deformation process of materials is mainly represented by a linear function of gradient E, the plastic portion has been characterized by various exponential functions with an exponent n that varies with its chemical composition, the level of work hardening and the material in question among others. Recycled steel, whose composition depends on the source and availability of its raw material, has an extremely vulnerable n-value. In this paper, the effect of the boron content in recycled steel on the n-value of thermo-mechanically treated bars made from it has been studied. To do this, TMT bars were subjected to tensile testing and the corresponding force extension diagrams plotted. The values of εi10 and εi20 for the interval between 10% and 20% deformation respectively were determined to correspond to the stress values σi10 and σi20 so that was calculated as the ruling n-value for each interval. Spectro-analysis was used to determine the chemical composition of the samples so that the percentage boron content by weight was plotted against the n-value. The growth of the n-value with boron content has been shown to obey a polynomial function and to enhance the tendency to strain-hardening, implying early onset of failure in pronounced cold deformation.Item Open Access Stochastic Modeling of Internet Service for Profit Optimization in Uganda(IST-Africa, 2018) Christopher, Senfuka; Paul, Kizito Mubiru; Maureen, N. SsempijjaWe consider an internet cafe faced with an optimal choice of bandwidth for internet users under stochastic stationary demand. The choice is made over uniformly time horizons with a goal of optimizing profits. Considering customer demand, price and operating costs of internet service, we formulate a finite state Markov decision process model where states of a Markov chain represent possible states of demand for internet service. A profit matrix is generated; representing the long run measure of performance for the Markov decision process problem. The problem is to determine an optimal bandwidth adjustment policy so that the long run profits are maximized for a given state of demand. The bandwidth adjustment policies are determined using dynamic programming over a finite period planning horizon. Results from a case study demonstrate the existence of an optimal statedependent option for bandwidth adjustment and profits in providing internet service.Item Open Access Modeling Campaign Optimization Strategies in Political Elections under Uncertainty(International Journal of Scientific Research in Mechanical and Materials Engineering, 2018) Christopher, Senfuka; Paul, Kizito Mubiru; Maureen, N. SsempijjaIn most political campaigns,the overall goal of every candidate is to maximize the number of voters during the election exercise.In such an effort,cost effective methods in choosing the optimal campaign strategy areparamount.In this paper, a mathematical model is proposed that optimize campaign strategies of a political candidate.Considering uncertainty in voter support and cost implications in holding political rallies,we formulate a finite state markov decision process model where states of a markov chain represent possible states of support among voters.Using daily equal intervals,thecandidates‟s decision of whether or not to campaign and hold a political rally at a given location were made using discrete time Markov chains and dynamic programming over a finite period planning horizon.Empirical data was collected from two locations on a daily basis during the campaign exercise.The data collected was analyzed and tested to establish the optimal campaign strategy and costs at the respective locations.Results from the study indicated the existence of an optimal state-dependent campaign strategy and costs at the respective political rally locations.Item Open Access Extending measurement range for three-dimensional structured light imaging with digital exponential fringe pattern(The 2nd Annual Higher Education Conference, Hotel Africana Kampala, Uganda, 2020) Abel, KamagaraIn this paper, a method and an approach for intrinsically extending the measurement range for digital fringe projection profilometry with structured light imaging techniques is presented. This approach exploits the fact that at low levels of defocusing, exponential binary-coded fringe pattern exhibits a quasi-sinusoidal form having intact binary structures with reduced or negligible errors owing to high-order harmonic robustness during fringe generation. Experimental simulations and results show that within the desired region of defocus or at an extended measurement range, the proposed method exhibits a 45% comparative reduction in root-mean-square phase error hence improvement in final measurement result.Item Open Access Effective Application of 4th Industrial Revolution Technologies During Engineering Research and Teaching in Ugandan Universities(The 2nd Annual Higher Education Conference, Hotel Africana Kampala, Uganda, 2020) Isaac, Ndawula; Dianah, Asiimwe; Samuel, S. Mushakangoma; Pascal Musaazi, SenkinduThe 4th Industrial Revolution (4IR) technologies is the recent research topic of interest among the academicians, since the 4IR technologies make up the latest era of digitization. The 4IR technologies demands changes in the three fundamental functions (teaching, research and community service) of higher institutions of learning. Each revolution technologies needs different job skills and competences, the 4IR technologies will also require new job skills and competences from the university graduates particularly in the field of engineering. The teaching staff at universities shall play an important role in imparting the necessary job skills and competences to graduates. Recently several research on 4IR technologies in higher institutions of learning has been presented, but none is addressing the issue of availability of effective utilization of 4IR technologies in engineering education. So, this paper presents the investigation of the availability of effective application of 4IR technologies during university engineering research and teaching in Ugandan universities. The paper also examined the behavior, knowledge, and perception of teaching staff towards 4IR technologies in the university engineering education in Uganda. 256 respondents were interviewed using online questionnaire and data collected was analyzed using MATLAB program. The findings disclose that there is low degree of application of 4IR technologies by teaching staff in engineering sector during teaching and research in the seven universities in Uganda.