SAIEE Africa Research Journal最新文献

{"title":"Editors and reviewers","authors":"","doi":"10.23919/SAIEE.2024.10463749","DOIUrl":"https://doi.org/10.23919/SAIEE.2024.10463749","url":null,"abstract":"","PeriodicalId":42493,"journal":{"name":"SAIEE Africa Research Journal","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2024-03-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10463749","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140066450","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Self-synchronizing on-off-keying visible light communication system for intra- and inter-vehicle data transmission","authors":"S. Achari;A. Y. Yang;J. Goodhead;B. Swanepoel;L. Cheng","doi":"10.23919/SAIEE.2024.10463748","DOIUrl":"https://doi.org/10.23919/SAIEE.2024.10463748","url":null,"abstract":"Visible light communication is a present technology which allows data to be transmitted by modulating information onto a light source. It has many advantages over traditional radio frequency communication and up to 10,000 times larger bandwidth. Many existing research in visible light communication assumes a synchronized channel, however, this is not always easily achieved. This paper proposes a novel synchronized VLC system with the potential to ensure reliable communication in both intra- and inter-vehicle communication. The protocol achieves synchronization at the symbol level using the transistor-transistor logic protocol and achieves frame synchronizations with markers. Consequently, the deployment of the system in both intra- and inter-vehicle communication may present numerous advantages over existing data transmission processes. A practical application where visible light communication is used for media streaming is also previewed. In addition, various regions of possible data transmission are determined to infer forward error correction schemes to ensure reliable communication.","PeriodicalId":42493,"journal":{"name":"SAIEE Africa Research Journal","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2024-03-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10463748","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140067551","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Green hydrogen: A clean energy solution for Germany's transportation sector","authors":"A. D. Asiegbu;M. T. E. Kahn;A. M. Almaktoof","doi":"10.23919/SAIEE.2024.10463751","DOIUrl":"https://doi.org/10.23919/SAIEE.2024.10463751","url":null,"abstract":"The need for sustainable and environmentally friendly energy sources is very important if future generations are to be spared of the misdoings of past generations. Climate change, environmental pollution, radiation pollution, and altering of the balanced ecology of the green planet earth is now a significant challenge, because if not mitigated, some island nations will disappear in the future, due to human activities energized by unsustainable fossil fuels. Based on these facts, Germany has taken concrete and important steps to stem the tide of this ill wind by embracing the Green Hydrogen system. This is more obvious in the transport system that produces more than 40% of Green House Gases in Europe. Because Germany is an industrialized European nation, the government has introduced Green Hydrogen for transportation in accordance with European Union energy policy. Therefore, this paper provides a clear, concise analysis and implementation of Green Hydrogen energy in the smart energy system. The paper presents Green Hydrogen analysis in transportation in four sections, namely, Geographical, Chemical, social, and economic aspects, respectively. The last section of this paper is the discussion of results from cost/feasibility analysis, which shows that although the expected or forecasted GH cost is US$7.11per kg from 2020 to 2050, the current growth in the green hydrogen infrastructure and technology, reduced the overall cost of GH in 2020 to $1.60/kg. An erudite conclusion and recommendations are made at the end of this research.","PeriodicalId":42493,"journal":{"name":"SAIEE Africa Research Journal","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2024-03-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10463751","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140067561","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluation of unconventional partial discharge and tan delta assessment techniques on medium voltage cable terminations with artificial defects","authors":"J. V. Bissett;P. A. van Vuuren;J. J. Walker","doi":"10.23919/SAIEE.2024.10463754","DOIUrl":"https://doi.org/10.23919/SAIEE.2024.10463754","url":null,"abstract":"Reliable cable systems are of utmost importance for electricity distribution- and grid networks. Cable terminations are key components of cable systems but also contribute significantly towards unwanted cable failures and power outages. Although well-developed standards exist in the electricity industry, it is not always possible to execute the most effective tests at power frequency due to financial or logistical reasons. Hence, withstand voltage- and Partial Discharge tests at power frequency are only conducted at a low percentage of electricity utilities. This paper presents the evaluation of unconventional partial discharge fault detection techniques and Very Low Frequency Tan Delta measurements on different cable termination defects. Five artificial cable termination defects were created on single core 6.35/11kV cross linked polyethylene cables, with one “defect-free” termination and five defective ones. Power frequency voltage was applied at increased voltage steps to initiate aging acceleration due to partial discharge. This resulted in insulation deterioration and eventual termination failure. Different data sets were obtained from the Very Low Frequency Tan Delta measurements as well as for the unconventional Partial Discharge measurements. The sequence of failures is compared between the two data sets and evaluated against the root cause failures of the terminations as evaluated by an industry expert. High Frequency Current Transformer and capacitive coupling sensors were used together with an advanced partial discharge data acquisition system. Partial discharge analysis was done to relate the specific on-line trending data with termination failure. Good correlation was found between the two data sets which supports the utilization of unconventional partial discharge measurement for cable acceptance testing. It would be beneficial for the electricity industry to consider unconventional Partial Discharge technology as a suitable alternative for on-site acceptance tests for cable terminations.","PeriodicalId":42493,"journal":{"name":"SAIEE Africa Research Journal","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2024-03-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10463754","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140067562","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Notes for authors","authors":"","doi":"10.23919/SAIEE.2024.10463753","DOIUrl":"https://doi.org/10.23919/SAIEE.2024.10463753","url":null,"abstract":"","PeriodicalId":42493,"journal":{"name":"SAIEE Africa Research Journal","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2024-03-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10463753","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140067552","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Notes for authors","authors":"","doi":"10.23919/SAIEE.2024.10520214","DOIUrl":"https://doi.org/10.23919/SAIEE.2024.10520214","url":null,"abstract":"","PeriodicalId":42493,"journal":{"name":"SAIEE Africa Research Journal","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2024-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10520214","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140826044","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Techno-Economic Modeling of Stand-Alone Solar Photovoltaic Systems: A Case Scenario from South Sudan","authors":"Aban Ayik;Nelson Ijumba;Charles Kabiri;Philippe Goffin","doi":"10.23919/SAIEE.2024.10520213","DOIUrl":"https://doi.org/10.23919/SAIEE.2024.10520213","url":null,"abstract":"South Sudan is expansive and sparsely populated with over 80% of the population living in rural areas. The country has no national grid connecting its cities and towns, thus making rural areas “good candidates” for stand-alone renewable energy systems. This study was conducted to determine the technical feasibility and economic viability of a stand-alone photovoltaic (PV) system compared to a diesel generator. A technoeconomic model was developed to forecast the performance of the PV system. The system was initially designed using the IEEE Recommended Practice for Sizing of Stand-Alone Photovoltaic Systems (IEEE P1562-2021) and the IEEE Recommended Practice for Sizing Lead-Acid Batteries for Stand-Alone Photovoltaic Systems (IEEE 1013-2019). The solar radiation data used for modeling were acquired from the Ineichen clear sky model and then transposed to the plane of array irradiation using pvlib python. The system optimization and sensitivity analysis was performed under various diesel fuel costs using the Hybrid Optimization of Multiple Energy Resources (HOMER) software. Results show that at a fuel price of $ 2 per liter, the levelized cost of electricity (LCOE) of the PV system is 64% lower than that of the diesel generator and that the system can earn 11% return on investment (ROI) and recover the investment in about 5.5 years. With a drop in price of diesel fuel to $1 per liter, the payback period increases to about 7 years. These results show that standalone PV systems are technically feasible and economically viable in rural and peri-urban areas of South Sudan.","PeriodicalId":42493,"journal":{"name":"SAIEE Africa Research Journal","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2024-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10520213","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140826007","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Editors and reviewers","authors":"","doi":"10.23919/SAIEE.2024.10520216","DOIUrl":"https://doi.org/10.23919/SAIEE.2024.10520216","url":null,"abstract":"","PeriodicalId":42493,"journal":{"name":"SAIEE Africa Research Journal","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2024-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10520216","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140826030","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Feasibility of Positioning Electromagnetic Near Field Hotspots within a Resonant Cavity for Microwave Thermal Ablation","authors":"Graeme Young;David Rubin;Alan Clark","doi":"10.23919/SAIEE.2024.10520211","DOIUrl":"https://doi.org/10.23919/SAIEE.2024.10520211","url":null,"abstract":"An investigation into moving electromagnetic nearfield hotspots inside a resonant cavity is presented. The investigation focused on simulating an alternative approach to microwave thermal ablation of tumours by manipulating the interaction between electromagnetic near fields instead of utilising an interstitial antenna. The methodology comprised comparing various electromagnetic field solvers, verifying the simulation techniques, characterising a rectangular resonant cavity, and attempting to manipulate the position of its hotspots by introducing a feed phase shift. The effects of dielectric media were also investigated. Progressive hotspot movement was achieved using input phase manipulation between 2.55 and 2.7 GHz with the feeds on opposite walls. No pattern change was evident at the system's eigenfrequencies, indicating a constant field pattern at its resonant peaks. Furthermore, it was determined that the characteristic modes of the system were narrowband, such that the addition of dielectric material altered the system's resonance. Therefore, the application of this method to thermal ablation, which requires high precision, accuracy and control, was deemed impractical. Future recommendations include using adjustable geometry to design field patterns, comparing dielectric media with significant thermal mass, and investigating the ‘inverse problem’ to create a specific current distribution around the resonant cavity and induce the desired hotspot patterns.","PeriodicalId":42493,"journal":{"name":"SAIEE Africa Research Journal","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2024-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10520211","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140826029","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Using LSTM to Perform Load Predictions for Grid-Interactive Buildings","authors":"Kyppy N. Simani;Yuval O. Genga;Yu-Chieh J. Yen","doi":"10.23919/SAIEE.2024.10520212","DOIUrl":"https://doi.org/10.23919/SAIEE.2024.10520212","url":null,"abstract":"Energy consumption from the residential sector forms a large portion of the electricity grid demand. The growing accessibility of residential load profile data presents an opportunity for improved residential load forecasting and the implementation of demand-side management (DSM) strategies. Machine learning is a tool well-suited for predicting stochastic processes, such as residential power usage due to human behavior. Long short-term memory (LSTM) recurrent neural networks are especially suited for predicting time-series data such as electrical load profiles. This paper investigates the impact of LSTM hyperparameters to the predictive performance of models, which include the tradeoffs associated with training data size, horizon ratios, model fidelity, prediction horizon and computational intensity. This paper provides a framework to evaluate the choice of LSTM hyperparameters for understanding trade-offs in a practical application of load profile predictions for the context of Grid-interactive Efficient Buildings (GEBs).","PeriodicalId":42493,"journal":{"name":"SAIEE Africa Research Journal","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2024-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10520212","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140826043","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}