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    Performance analysis of VOIP codec schemes and queuing techniques and their impact on FTP and video conferencing.
    (The University of Zambia., 2024) Munthali, Emma
    Advancement in internet technology allows for the integration of network traffic i.e data, video and voice into a single network. This technology offers many benefits but also presents some challenges. Real time traffic services such as Voice over Internet Protocol (VoIP) and video require certain Quality of Service (QoS) from the network which cannot be guaranteed on the internet therefore, maintaining the right QoS parameters becomes all the more important. Studies have been carried out on the effect of congestion management tools while others compare the effects of such tools on the quality of VoIP. However, in reality, these tools are not used in isolation in a network and most networks do not support single traffic only. The goal of this research therefore is to compare the effects of the combinations of some of these tools (i.e queuing techniques and codec schemes) on the quality of VoIP and to determine their influence on the rest of the traffic on a network. Simulation approach using the OPNET Modeler 14.5 tool was used to simulate a network supporting three different types of traffic namely: FTP traffic, Video conferencing traffic and VoIP traffic. While maintaining the same topology and traffic of the network, G711 and G729 codec schemes and queuing techniques namely; First in First out (FIFO), Priority Queuing (PQ), Custom Queuing (CQ) and Weighted Fair Queuing (WFQ) were tested resulting in different scenarios. Custom Queuing technique showed the best performance overall except for the amount of video conferencing traffic received where it had the worst performance. WFQ and FIFO suffered the highest delay for video and VoIP traffic respectively while FTP traffic suffered from starvation in PQ. The graphs were observed to follow the same pattern regardless of the codec scheme used however, G729 performed the better of the two as it produced higher throughputs and slightly lower delays compared to G711. G729 would best be used for low bandwidth networks while G711 would be ideal for networks with higher bandwidths and where VoIP communication is the main priority.
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    Investigation of how operational and climatic factor affect PV-grid tied inverter: a case study of Ethiopia and Zambia.
    (The University of Zambia., 2023) Redate, Shawell Endalamaw
    Zambia and Ethiopia are two countries from southern and eastern of Africa due to their geographical location and other factor the environment condition is different. The research aims to Investigation how operational and climatic factor affect PV-grid tied inverter. In Zambia the study focused on the two main solar plants which is under ZESCO national grid at malty facility zone (MFZ), the first one is the 54 megawatts Bangweulu solar power plant, second one is 34MW Ngonye solar photovoltaic (PV) plant. In Ethiopia eight min off-grid site under Ethiopian Electric Utility (EEU) is included. Beltu, Behima, Mino, Ungoge, Korhele,Tum, Omorate and Kofetu. A survey is conducted how operational and climatic factor affect PV-grid tied inverter (GTI) in the above-mentioned area. Using Microsoft excel the environmental \climate condition, Solar radiation, Air temperature and Rain falls of the two country Zambia and Ethiopia is investigated and analysed for each selected site. A questionnaire and a Simi-structure interview are conducted. The basic inverter challenges are investigated from the collected data and the problem is analyzed based on the specific inverter data sheet. The data sheets of the inverter for each site under this study are attached. Environmental condition affects almost all solar plant sites which are under this study. The temperature of Lusaka is higher than Addis Ababa by 5.63°C and even in the plant under this study; temperature rise is one of the challenges on the inverter performance, sensitive electronic component bent due to excessive temperature. On the other side in Ethiopia Addis Ababa excessive rain affect the inverter. Addis Ababa has about 1.32 times more rainfall than Lusaka, (Addis Ababa’s 79.54mm vs Lusaka’s average of 60.34mm). For that reason, most of the inverter in Ethiopia on the mini off-grid site is affected by heavy rain condition. Finally, the real-time performance of the inverter of the off-grid PV mini-grid system installed in a small remote town in Ethiopia is analyzed using measured meteorological data. From on- grid and off-grid inverter performance challenges, which the researcher collected from different plant the main ones are climate or environmental effect and also over load. Overload is one of the frequent challenges in koftu, behama and amorita this can be due to high population growth and unexpected power demand from the community.
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    Design and implement a crop management system for farmers in Chongwe district of Zambia.
    (The University of Zambia., 2024) Chikanwa, Gregory Kakoma
    This article highlights the important role of agricultural extension services for Zambian farmers, despite challenges in reaching remote areas. The government of the republic of Zambia has been using ICT to provide rural and remote farmers with e-Extension services through the Ministry of Agriculture website to help in agricultural planning. This application supplements traditional methods, offering a comprehensive solution to enhance crop production in Chongwe District. The growth of Zambia's agriculture sector relies on timely detection and treatment of crop diseases, with the support of agriculture extension officers but the services were hindered by impact COVID-19's. Zambia's government is countering this by adopting electronic extension services, supported by provision of e-Extension services. Insufficient extension officers and reduced funding lead to inadequate support for farmers in Chongwe District. Additionally, the existing e-extension portal currently being used lacks user-friendliness and comprehensive data, which affects crop management. The purpose of this study was to develop and implement a crop management system that will support agriculture production in Chongwe District, providing expert information on crop production and management. The study examined how extension officers in Chongwe district deliver services to remote farmers, assessing current e-extension services' effectiveness and seeking ways to improve user experience. The literature review provided a historical overview of farming practices and explored web-based extension services' emergence, comparing various mobile applications being used by farmers. However, limitations in existing systems, such as lack of comprehensive information and focus on specific crops, were identified. The efforts to enhance extension services in Zambia using technology, that addresses issues like crop management and disease were identified. Studies identified the integration of video tutorials into e-extension services was for agricultural education and training. Videos offer visual demonstration, efficient learning, and standardization of information, improving adoption of best practices among farmers. Embracing digital solutions like mobile applications and video tutorials enhances agricultural extension services, increasing crop production and supporting farmers' livelihoods. Recent developments in Precision Agriculture (PA) sparked academic interest in Farming Management Information Systems (FMIS), aiming to boost efficiency. Research focuses on Decision Support Systems (DSS), computational models, and systems which are user friendly. Usability is key for adoption, however designing user interfaces faces challenges due to dispersed end-users with limited IT expertise. Microservice architecture suggests use of agile methodology to develop FMIS. Agile ethodologies enable swift adaptation to dynamic conditions, fostering communication and collaboration among stakeholders. Developers use Agile methodology to create applications in short bursts, focusing on developing, coding, and testing features to deliver a usable product at the end of each sprint. In the System Development Process, requirements analysis involves meetings with agricultural experts to understand existing systems and define scope. In this study the researcher held meetings with the agriculture extension experts from the ministry of to develop a new system for the farmers in Chongwe with features user-friendly interfaces, multimedia integration, mobile accessibility, and tailored content for local farmers, bridging the gap between tradition farming and the use of ICT to enhance productivity and farmers livelihoods.
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    Internal stakeholder management in ZESCO distribution projects.
    (The University of Zambia., 2024) Mundia, Sililo
    Stakeholders have influence on both project performance and success. This study investigated internal stakeholder management in ZESCO distribution projects. The main objective of the study was to develop a framework for internal stakeholder management. The specific objectives of the study were to: determine factors influencing stakeholder management on ZESCO distribution projects; establish the degree of influence of stakeholder engagement on the performance of ZESCO distribution projects; determine the impact of stakeholder mapping on the performance of ZESCO distribution projects; and examine the relationship between stakeholder management and the performance of ZESCO distribution projects. The study employed a mixed method research approach, incorporating both qualitative and quantitative methods. The sample was drawn from ZESCO employees engaged in distribution projects, and data was gathered through interviews and questionnaires. The findings underscored the critical role of effective stakeholder mapping, engagement and management in the success of ZESCO distribution projects. Addressing internal stakeholders’ concerns and proper engagement positively influences project performance. It was further established that engaging internal stakeholders at various project stages improves project delivery time. The findings also indicated that stakeholder mapping is valuable executing projects within schedule, cost management, environmental considerations, and conflict resolution. It was concluded that stakeholder management has an impact on project performance parameters of cost, time and quality. Comprehensive training programs in project management and awareness campaigns about the project management procedures were recommended. It was established that the internal stakeholder management framework developed by the study can help improve project performance in ZESCO distribution projects.
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    Performance evaluation of internet protocol security (IPSec) over multiprotocol label switching (MPLS).
    (The University of Zambia., 2024) Mwape, Jessy Chisenga
    For nearly two (2) decades, Multiprotocol Label Switching (MPLS) has provided Wide Area Network (WAN) solutions for enterprises and large organizations to manage their multiple networks in different locations. Real time networks have been affected negatively by high latency due to inefficient WAN technologies and security solutions. The popularity of Multi-protocol Label Switching (MPLS) continues to increase with Internet and Data Service providers (ISP) in Zambia. MPLS provides network efficiency through traffic engineering and Quality of Service, however, by default, it does not provide any mechanism for authentication and encryption of the data as it travels through the public network provided by Internet service providers. In order to resolve the security concerns in MPLS, this study has deployed the Internet Protocol Security (IPsec) over MPLS in order to provide additional layer of security to data during transmission. The method used to conduct this research is experiments. The research is conducted in a live environment where the service provider network implements MPLS and IPsec is deployed on Customer edge routers. Three (3) Customer Edge routers over the ISPs MPLS public network were deployed in different locations and configured with policy based IPsec. Data was collected before IPsec deployment and after IPsec deployment in order to analyze the performance metrics such as packet lengths, round trip times, authentication and encryption. The study captured and analyzed 15,362,356 packets. It has been established that using MPLS provides minimal security to data through the use of labels. This label feature both separates traffic streams and provides efficient use of network resources as IP addresses are not used to route traffic in the MPLS environment. It is worth noting that implementing IPsec over MPLS improves the security of the network and data. The study has shown that IPsec and MPLS are better together because the security risks associated with transmitting data over MPLS are resolved by IPsec. IPsec provides data privacy and security per connection for network traffic crossing the perimeter. Further, the authentication of peers and data provides the mechanism of identification and verifying the IPsec peers and validating the authenticity of the data send against the one received.