This paper describes an audio digital signal-processing toolkit that the authors develop to supplement a lecture course on digital signal processing (DSP) taught at the department of Electrical and Electronics Enginee...This paper describes an audio digital signal-processing toolkit that the authors develop to supplement a lecture course on digital signal processing (DSP) taught at the department of Electrical and Electronics Engineering at the University of Rwanda. In engineering education, laboratory work is a very important component for a holistic learning experience. However, even though today there is an increasing availability of programmable DSP hardware that students can largely benefit from, many poorly endowed universities cannot afford a costly full-fledged DSP laboratory. To help remedy this problem, the authors have developed C#.NET toolkits, which can be used for real-time digital audio signal processing laboratory. These toolkits can be used with any managed languages, like Visual Basic, C#, F# and managed C++. They provide frequently used modules for digital audio processing such as filtering, equalization, spectrum analysis, audio playback, and sound effects. It is anticipated that by creating a flexible and reusable components, students will not only learn fundamentals of DSP but also get an insight into the practicability of what they have learned in the classroom.展开更多
Biometric authentication systems are believed to be effective compared to traditional authentication systems. The introduction of biometrics into smart cards is said to result into biometric-based smart ID card with e...Biometric authentication systems are believed to be effective compared to traditional authentication systems. The introduction of biometrics into smart cards is said to result into biometric-based smart ID card with enhanced security. This paper discusses the biometric-based smart ID card with a particular emphasis on security and privacy implications in Rwanda universities environment. It highlights the security and implementation issues. The analysis shows that despite the necessity to implement biometric technology, absence of legal and regulatory requirements becomes a challenge to implementation of the proposed biometric solution. The paper is intended to engage a broad audience from Rwanda universities planning to introduce the biometric-based smart ID cards to verify students and staff for authentication purpose.展开更多
There are obstacles to the widespread use of small electric vehicles(EVs)in Rwanda,including concerns regarding the battery range and lifespan.Lithium-ion batteries(LIBs)play an important role in EVs.However,their per...There are obstacles to the widespread use of small electric vehicles(EVs)in Rwanda,including concerns regarding the battery range and lifespan.Lithium-ion batteries(LIBs)play an important role in EVs.However,their performance declines over time because of several factors.To optimize battery management systems and extend the range of EVs in Rwanda,it is essential to understand the influence of the driving profiles on lithium-ion battery degradation.This study analyzed the degradation patterns of a lithium-ion battery cell that propels an E-bike using various real-world E-bike driving cycles that represent Rwandan driving conditions under deep discharge(>80%).By being aware of these variables,battery failure can be slowed and improved battery performance can be achieved to promote the transition to cleaner transportation in Rwanda for the productive use of energy.The analyzed parameters that affect battery performance are temperature,driving cycles,and state of charge.It was found that the higher the temperature,the higher was the rate of fading.On the other hand,the EVs that operate in the region with higher elevation(hilly region)combined with a flat surface where the riders use their physical forces to propel the E-bike and their batteries lose their capacity rapidly compared to those operating in regions where the energy from the lithium-ion battery assists for the entire mileage.By draining the battery to 10%and charging it to 90%of its initial capacity,the capacity fading decreased by 5%.展开更多
Renewable energy exploitation is among the development strategies set by the government of Rwanda on the roadmap to 2023/2024 universal electricity access and theUnitedNations plans by 2030.Numerous previous studies o...Renewable energy exploitation is among the development strategies set by the government of Rwanda on the roadmap to 2023/2024 universal electricity access and theUnitedNations plans by 2030.Numerous previous studies oncleanenergy technologies inRwandahavemostly focusedonhouseholds’usagebut there are currentlynostudies describing the feasibility of clean energy technologies for financial institutions.The skepticism on renewable energy in Africa was previously reported by some personnel.Having realized that most SACCOs(Savings and Credit Co-Operatives)in Rwanda use diesel technology for backup/emergency electricity supply,taking consideration of abundant solar resources in Rwanda,having seen the viability and feasibility studies from other countries of renewable energy for different institutions(financial included);thiswork uses theHOMEREnergy Software and the electricity load profile of a typical SACCO in Rwanda to analyse the affordability and viability of on-site renewable energy generation for SACCO in Rwanda.The results reveal that a solar PV systemwith storage can be the optimal solution(with levelized cost of electricity(LCOE)of 0.713$/kWh which is cheaper than 0.73$/kWh for diesel technology)for SACCOs located in both off-grid areas and grid-connected areas(with 0.041$/kWh LCOE which is lower than the current electricity tariff in Rwanda).The findings in this work can serve as basic tools/materials for policy drafters in Rwanda on how financial institutions can contribute to climate change mitigation through self-renewable energy exploitation.展开更多
Offsetting particulate matter emissions has become a critical global aim as there are concerted efforts to deal with environmental and energy poverty challenges.This study consists of investigations of computing emiss...Offsetting particulate matter emissions has become a critical global aim as there are concerted efforts to deal with environmental and energy poverty challenges.This study consists of investigations of computing emissions of particulate matter from biomass fuels in various atmospheres and temperatures.The laboratory setup included a fixed bed electric reactor and a particulate matter(PM)measuring machine interfaced with the flue gas from the fixed bed reactor combustion chamber.The experiments were conducted at seven different temperatures(600℃-1200℃)and six incremental oxygen concentrations(21%-100%).Five biomass types were studied;A-cornstalk,B-wood,C-wheat straw,D-Rice husk,E-Peanut shell,each pulverized to a size of approximately 75 microns.The study shows that PM emitted during char combustion is consistently higher than that emitted during the de-volatilization.During de-volatilization,increase in temperature leads to linear decrease in PM emission between atmospheres of 21%O_(2)to 50%O_(2),thereafter,between 70%O_(2)to 100%O_(2);increase in temperature leads to a rise in PM emission.The average PM formation from all the five considered biomass is relatively comparable however,with differing atmospheres and temperatures,the fibrous and low-density biomass forms more PM.During char combustion,the study shows that at oxygen levels of 21%,70%,90%and 100%,increase in temperature leads to increased PM emission.The increase in oxygen concentration and temperature increases the rate of combustion hence diminishing the time of combustion.展开更多
Renewable technologies such as solar present some of the possibilities for indoor and outdoor lighting in the remotest rural Africa where grid connections may take ages.This paper examined the key determinants that dr...Renewable technologies such as solar present some of the possibilities for indoor and outdoor lighting in the remotest rural Africa where grid connections may take ages.This paper examined the key determinants that drive household lighting fuel using a nationally representative sample(14,415 households)across Rwanda.Results from a multinomial probit regression show that rural location,house ownership,household wealth,and nonfarm work are some of significant factors that influence lighting fuel choices in Rwanda.Robustness of the results indicates that household wealth levels and other regional differences are likely to influence choice probability for using clean energy sources such as solar confirming the need to priotise wealth generation.The study’s findings suggest the need for joint efforts by government and non-state actors to priotise household wealth generation,promotion of non-farm activities and improvement of infrastructures to reduce rural-urban bias and differences across the regions,assuming that wealth will motivate rural households to switch to clean energy sources.展开更多
文摘This paper describes an audio digital signal-processing toolkit that the authors develop to supplement a lecture course on digital signal processing (DSP) taught at the department of Electrical and Electronics Engineering at the University of Rwanda. In engineering education, laboratory work is a very important component for a holistic learning experience. However, even though today there is an increasing availability of programmable DSP hardware that students can largely benefit from, many poorly endowed universities cannot afford a costly full-fledged DSP laboratory. To help remedy this problem, the authors have developed C#.NET toolkits, which can be used for real-time digital audio signal processing laboratory. These toolkits can be used with any managed languages, like Visual Basic, C#, F# and managed C++. They provide frequently used modules for digital audio processing such as filtering, equalization, spectrum analysis, audio playback, and sound effects. It is anticipated that by creating a flexible and reusable components, students will not only learn fundamentals of DSP but also get an insight into the practicability of what they have learned in the classroom.
文摘Biometric authentication systems are believed to be effective compared to traditional authentication systems. The introduction of biometrics into smart cards is said to result into biometric-based smart ID card with enhanced security. This paper discusses the biometric-based smart ID card with a particular emphasis on security and privacy implications in Rwanda universities environment. It highlights the security and implementation issues. The analysis shows that despite the necessity to implement biometric technology, absence of legal and regulatory requirements becomes a challenge to implementation of the proposed biometric solution. The paper is intended to engage a broad audience from Rwanda universities planning to introduce the biometric-based smart ID cards to verify students and staff for authentication purpose.
基金supported by the Global Challenges Research Fund(GCRF)through the Engineering and Physical Sciences Research Council UK under project RENGA(EP/R030235/1)It was also funded by the African Center of Excellence in Energy for Sustainable Development(ACE-ESD)under the University of Rwanda,College of Science and Technology.
文摘There are obstacles to the widespread use of small electric vehicles(EVs)in Rwanda,including concerns regarding the battery range and lifespan.Lithium-ion batteries(LIBs)play an important role in EVs.However,their performance declines over time because of several factors.To optimize battery management systems and extend the range of EVs in Rwanda,it is essential to understand the influence of the driving profiles on lithium-ion battery degradation.This study analyzed the degradation patterns of a lithium-ion battery cell that propels an E-bike using various real-world E-bike driving cycles that represent Rwandan driving conditions under deep discharge(>80%).By being aware of these variables,battery failure can be slowed and improved battery performance can be achieved to promote the transition to cleaner transportation in Rwanda for the productive use of energy.The analyzed parameters that affect battery performance are temperature,driving cycles,and state of charge.It was found that the higher the temperature,the higher was the rate of fading.On the other hand,the EVs that operate in the region with higher elevation(hilly region)combined with a flat surface where the riders use their physical forces to propel the E-bike and their batteries lose their capacity rapidly compared to those operating in regions where the energy from the lithium-ion battery assists for the entire mileage.By draining the battery to 10%and charging it to 90%of its initial capacity,the capacity fading decreased by 5%.
基金Fujian Provincial Department of Science and Technology(Grant Number:2021I0014)Fujian Provincial Department of Housing and Construction(Grant Number:2022-K-67+5 种基金Fujian Provincial Department of Education(Grant Number:JAT201518)Additionally,Authors are grateful to Quanzhou Tongjiang Scholar Special Fund for financial support throughGrant Number:(600005-Z17X0234)Quanzhou Science and Technology Bureau for financial support through Grant Number:(2018Z010)Huaqiao University through Grant Number:(17BS201)the Fujian Provincial Department of Science and Technology for financial support through Grant(2018J05121)Authors are also grateful for financial support from the Fujian Provincial Department of Science and Technology through Grants Numbers:2021I0014 and 2018J05121.
文摘Renewable energy exploitation is among the development strategies set by the government of Rwanda on the roadmap to 2023/2024 universal electricity access and theUnitedNations plans by 2030.Numerous previous studies oncleanenergy technologies inRwandahavemostly focusedonhouseholds’usagebut there are currentlynostudies describing the feasibility of clean energy technologies for financial institutions.The skepticism on renewable energy in Africa was previously reported by some personnel.Having realized that most SACCOs(Savings and Credit Co-Operatives)in Rwanda use diesel technology for backup/emergency electricity supply,taking consideration of abundant solar resources in Rwanda,having seen the viability and feasibility studies from other countries of renewable energy for different institutions(financial included);thiswork uses theHOMEREnergy Software and the electricity load profile of a typical SACCO in Rwanda to analyse the affordability and viability of on-site renewable energy generation for SACCO in Rwanda.The results reveal that a solar PV systemwith storage can be the optimal solution(with levelized cost of electricity(LCOE)of 0.713$/kWh which is cheaper than 0.73$/kWh for diesel technology)for SACCOs located in both off-grid areas and grid-connected areas(with 0.041$/kWh LCOE which is lower than the current electricity tariff in Rwanda).The findings in this work can serve as basic tools/materials for policy drafters in Rwanda on how financial institutions can contribute to climate change mitigation through self-renewable energy exploitation.
基金Authors are grateful to Quanzhou Tongjiang Scholar Special Fund for financial support through Grant No.(600005-Z17X0234)Quanzhou Science and Technology Bureau for financial support through Grant No.(2018Z010)+2 种基金Huaqiao University through Grant No.(17BS201)the Fujian ProvincialDepartment of Science and Technology for financial support through Grant(2018J05121)Authors are also grateful for financial support from the Fujian Provincial Department of Science and Technology through Grant Nos.2021I0014 and 2018J05121.
文摘Offsetting particulate matter emissions has become a critical global aim as there are concerted efforts to deal with environmental and energy poverty challenges.This study consists of investigations of computing emissions of particulate matter from biomass fuels in various atmospheres and temperatures.The laboratory setup included a fixed bed electric reactor and a particulate matter(PM)measuring machine interfaced with the flue gas from the fixed bed reactor combustion chamber.The experiments were conducted at seven different temperatures(600℃-1200℃)and six incremental oxygen concentrations(21%-100%).Five biomass types were studied;A-cornstalk,B-wood,C-wheat straw,D-Rice husk,E-Peanut shell,each pulverized to a size of approximately 75 microns.The study shows that PM emitted during char combustion is consistently higher than that emitted during the de-volatilization.During de-volatilization,increase in temperature leads to linear decrease in PM emission between atmospheres of 21%O_(2)to 50%O_(2),thereafter,between 70%O_(2)to 100%O_(2);increase in temperature leads to a rise in PM emission.The average PM formation from all the five considered biomass is relatively comparable however,with differing atmospheres and temperatures,the fibrous and low-density biomass forms more PM.During char combustion,the study shows that at oxygen levels of 21%,70%,90%and 100%,increase in temperature leads to increased PM emission.The increase in oxygen concentration and temperature increases the rate of combustion hence diminishing the time of combustion.
文摘Renewable technologies such as solar present some of the possibilities for indoor and outdoor lighting in the remotest rural Africa where grid connections may take ages.This paper examined the key determinants that drive household lighting fuel using a nationally representative sample(14,415 households)across Rwanda.Results from a multinomial probit regression show that rural location,house ownership,household wealth,and nonfarm work are some of significant factors that influence lighting fuel choices in Rwanda.Robustness of the results indicates that household wealth levels and other regional differences are likely to influence choice probability for using clean energy sources such as solar confirming the need to priotise wealth generation.The study’s findings suggest the need for joint efforts by government and non-state actors to priotise household wealth generation,promotion of non-farm activities and improvement of infrastructures to reduce rural-urban bias and differences across the regions,assuming that wealth will motivate rural households to switch to clean energy sources.
