SAIEE Africa Research Journal最新文献_第3页

Techno-Economic Modeling of Stand-Alone Solar Photovoltaic Systems: A Case Scenario from South Sudan 独立太阳能光伏系统的技术经济建模：南苏丹案例

IF 1.4

SAIEE Africa Research Journal Pub Date : 2024-03-03 DOI: 10.23919/SAIEE.2024.10520213

Aban Ayik;Nelson Ijumba;Charles Kabiri;Philippe Goffin

{"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":"115 2","pages":"55-68"},"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}

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Notes for authors 作者须知

IF 1.4

SAIEE Africa Research Journal Pub Date : 2024-03-03 DOI: 10.23919/SAIEE.2024.10520214

引用次数: 0

Editors and reviewers 编辑和审查员

IF 1.4

SAIEE Africa Research Journal Pub Date : 2024-03-03 DOI: 10.23919/SAIEE.2024.10520216

引用次数: 0

The Feasibility of Positioning Electromagnetic Near Field Hotspots within a Resonant Cavity for Microwave Thermal Ablation 在用于微波热消融的谐振腔内定位电磁近场热点的可行性

IF 1.4

SAIEE Africa Research Journal Pub Date : 2024-03-03 DOI: 10.23919/SAIEE.2024.10520211

Graeme Young;David Rubin;Alan Clark

{"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":"115 2","pages":"48-54"},"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}

引用次数: 0

Using LSTM to Perform Load Predictions for Grid-Interactive Buildings 使用 LSTM 为网格交互式建筑进行负荷预测

IF 1.4

SAIEE Africa Research Journal Pub Date : 2024-03-03 DOI: 10.23919/SAIEE.2024.10520212

Kyppy N. Simani;Yuval O. Genga;Yu-Chieh J. Yen

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Notes for authors 作者须知

IF 1.4

SAIEE Africa Research Journal Pub Date : 2023-11-15 DOI: 10.23919/SAIEE.2023.10319382

引用次数: 0

Editors and reviewers 编辑和审稿人

IF 1.4

SAIEE Africa Research Journal Pub Date : 2023-11-15 DOI: 10.23919/SAIEE.2023.10319376

引用次数: 0

An image encryption based on confusion-diffusion using two chaotic maps and Frobenius endomorphism 基于两个混沌映射和Frobenius自同态的混沌扩散图像加密

IF 1.4

SAIEE Africa Research Journal Pub Date : 2023-11-15 DOI: 10.23919/SAIEE.2023.10319378

Asmaa Hilmi;Soufiane Mezroui;Ahmed El Oualkadi

引用次数: 0

Radiofrequency electromagnetic radiation exposure assessment, analysis, computation, and minimization technique in 5G networks: A perspective on QoS trade-offs 5G网络中的射频电磁辐射暴露评估、分析、计算和最小化技术:QoS权衡的视角

IF 1.4

SAIEE Africa Research Journal Pub Date : 2023-11-15 DOI: 10.23919/SAIEE.2023.10319380

Adedotun T. Ajibare;Sunday O. Oladejo;Stephen O. Ekwe;Lateef A. Akinyemi;Daniel Ramotsoela

{"title":"Radiofrequency electromagnetic radiation exposure assessment, analysis, computation, and minimization technique in 5G networks: A perspective on QoS trade-offs","authors":"Adedotun T. Ajibare;Sunday O. Oladejo;Stephen O. Ekwe;Lateef A. Akinyemi;Daniel Ramotsoela","doi":"10.23919/SAIEE.2023.10319380","DOIUrl":"https://doi.org/10.23919/SAIEE.2023.10319380","url":null,"abstract":"In this study, the specific absorption rate (SAR) and exposure index (EI) of access points (APs) and user equipment (UEs) in fourth-generation (4G) and fifth-generation (5G) wireless technologies are examined with regard to the effects of exposure to radiofrequency (RF) electromagnetic fields (EMF) radiation and the implications of their reduction. We characterize the EI using a classical mathematical method while considering the power density, the SAR, the electric field strength, and the tissue's density and conductivity. As such, a novel exposure-index open-loop power control algorithm is proposed to evaluate the realistic RF-EMF radiation exposure on human users from both the downlink (DL) and uplink (UL) communication devices. To solve an EI minimization problem using the open-loop power control algorithm, we formulate it in the form of a mixed-integer nonlinear programming (MINLP) problem. As the energy capacity (i.e., power density) in wireless networks determines the radiation exposure (SAR and EI), it minimizes the EI by controlling and managing the transmitted and received powers under the restrictions of Quality of Service (QoS), interference, and power, while ensuring the users' QoS requirements are met. Our proposed scheme is numerically compared to other heuristic algorithms and exposure limits established by the International Commission on Non-Ionizing Radiation Protection (ICNIRP) and other similar organizations. Lastly, we compare the emissions from 4G and 5G networks to the emissions from UL and DL transmissions. Our simulation findings indicate that our proposed technique is a good alternative. Our assessment, in terms of numerical results and evaluation, also verifies that the exposures are bearable, fall within the recommended limits, and are minimized without impairing the users' QoS.","PeriodicalId":42493,"journal":{"name":"SAIEE Africa Research Journal","volume":"114 4","pages":"114-127"},"PeriodicalIF":1.4,"publicationDate":"2023-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10319380","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138138386","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}

引用次数: 0

GaN HEMT power amplifier design for 2.45 GHz wireless applications 用于2.45 GHz无线应用的GaN HEMT功率放大器设计

IF 1.4

SAIEE Africa Research Journal Pub Date : 2023-11-15 DOI: 10.23919/SAIEE.2023.10319379

Paula Akossiwa Atchike;Jamal Zbitou;Ahmed El Oualkadi;Pascal Dherbécourt

{"title":"GaN HEMT power amplifier design for 2.45 GHz wireless applications","authors":"Paula Akossiwa Atchike;Jamal Zbitou;Ahmed El Oualkadi;Pascal Dherbécourt","doi":"10.23919/SAIEE.2023.10319379","DOIUrl":"https://doi.org/10.23919/SAIEE.2023.10319379","url":null,"abstract":"Electronic devices with high performances like Power Amplifiers (PA) are very important for Wireless communications. This paper proposes a design of a class AB power amplifier operating at 2.45 GHz, in the S-band frequency. The Cree's CG2H40045F GaN HEMT (High Electron Mobility Transistor) is used for this design. The Gallium Nitride (GaN) technology has been chosen in light of its advantageous properties such as high breakdown voltage, high band gap, as well as high thermal conditions. The paper investigates the different design trade-offs for finding a good balance between various key parameters of the PA (linearity, efficiency, and gain). A design approach has been proposed and the microstrip lines based on the Smith Chart tool available in ADS software have been used for the matching process. The class AB was selected to reach a good agreement between linearity and efficiency, provided by this class. After various process applications from DC characterization to simulations, the proposed design achieves a power added efficiency more than 50% at power saturation with a gain of 15 dB in schematic simulation. The layout dimensions are 55.5 × 64.45 mm\u0000<sup>2</sup>\u0000 on PCB technology.","PeriodicalId":42493,"journal":{"name":"SAIEE Africa Research Journal","volume":"114 4","pages":"106-113"},"PeriodicalIF":1.4,"publicationDate":"2023-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10319379","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138138385","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}

引用次数: 0