SAIEE Africa Research Journal最新文献_第9页

Reconfiguration of Uganda's bulk network to accommodate a wholesale electricity market 乌干达大型电网的重组，以适应电力批发市场

IF 1.4

SAIEE Africa Research Journal Pub Date : 2021-08-13 DOI: 10.23919/SAIEE.2021.9513628

Jensen Nduhuura;Geofrey Bakkabulindi;Milton Edimu

{"title":"Reconfiguration of Uganda's bulk network to accommodate a wholesale electricity market","authors":"Jensen Nduhuura;Geofrey Bakkabulindi;Milton Edimu","doi":"10.23919/SAIEE.2021.9513628","DOIUrl":"https://doi.org/10.23919/SAIEE.2021.9513628","url":null,"abstract":"Countries that have restructured their electricity markets to wholesale markets have had significant benefits, including reduced generation costs, lower transmission losses and better consumer prices. In these markets, generators are dispatched in such a way that the financial benefits of both generator owners (producer surplus) and consumers (consumer surplus) are maximized. Retailers and large-scale consumers transact directly with power producers in a spot market or through contracts at wholesale level. Uganda's current single-buyer market (in which generation companies sell their power to a single entity that in turn transmits and sells it to distribution companies) was introduced in 2001 after the transition from a vertically integrated monopoly model. The market is expected to evolve into a wholesale market as the next restructuring step. This paper investigates the performance of the Uganda bulk network in a wholesale electricity market environment as modelled in Power World simulator. It considers different operation scenarios and possible infrastructure enhancements required for improved performance. Results showed that in the wholesale market model, transmission energy losses fell from an average of 4.3% to 3.8% compared to the single-buyer model due to more efficient network utilization. The economic analysis showed that off-peak and peak prices in the wholesale market system were 68.6% and 13.5% lower than in the current market respectively. However, old high loss transmission lines contributed to higher energy prices at receiving nodes. Transmission congestion, whose cost is embedded in a Location Marginal Price, caused sharp increases in the market's prices; this was addressed by using the network reconfiguration technique.","PeriodicalId":42493,"journal":{"name":"SAIEE Africa Research Journal","volume":"112 3","pages":"142-151"},"PeriodicalIF":1.4,"publicationDate":"2021-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/iel7/8475037/9513622/09513628.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67797004","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: 2

Editors and reviewers 编辑和评审

IF 1.4

SAIEE Africa Research Journal Pub Date : 2021-08-13 DOI: 10.23919/SAIEE.2021.9513624

引用次数: 0

Research on Payment Settlement Mode in Cross-border Business Trade Based on Blockchain Technology 基于b区块链技术的跨境商务贸易支付结算模式研究

IF 1.4

SAIEE Africa Research Journal Pub Date : 2021-07-22 DOI: 10.21203/rs.3.rs-735280/v1

Xiaoyan Wang

引用次数: 0

Classifying Economic Areas for Urban Planning using Deep Learning and Satellite Imagery in East Africa 利用深度学习和卫星图像对东非城市规划的经济区域进行分类

IF 1.4

SAIEE Africa Research Journal Pub Date : 2021-06-17 DOI: 10.36227/techrxiv.14779371

Davy Uwizera, C. Ruranga, P. McSharry

{"title":"Classifying Economic Areas for Urban Planning using Deep Learning and Satellite Imagery in East Africa","authors":"Davy Uwizera, C. Ruranga, P. McSharry","doi":"10.36227/techrxiv.14779371","DOIUrl":"https://doi.org/10.36227/techrxiv.14779371","url":null,"abstract":"In this research we use data from a number of different sources of satellite imagery. Below we describe and visualize various metrics of the datasets being considered. Satellite imagery is retrieved from Google earth which is supported by Data SIO (Scripps Institution of Oceanography), NOAA (National Oceanic and Atmospheric Administration), US. Navy (United States Navy), NGA (National Geospatial-Intelligence Agency), GEBCO (General Bathymetric Chart of the Oceans), Image Landsat, and Image IBCAO (International Bathymetric Chart of the Arctic Ocean). Using random sampling of spatial area in Kigali per target area, 342,843 thousands images were retrieved under the five categories: residential high income (78941), residential low income(162501), residential middle income(101401), commercial building, (67400) and industrial zone,(24400). For the industrial zone, we also included some images from Nairobi, Kenya industrial spatial area. The average number of samples for a category is 86929. The size of the sample per category is proportional to the size of the spatial target area considered per category. Kigali is located at latitude:-1.985070 and longitude:-1.985070, coordinates. Nairobi is located at latitude:-1.286389 and longitude:36.817223, coordinates.","PeriodicalId":42493,"journal":{"name":"SAIEE Africa Research Journal","volume":" ","pages":""},"PeriodicalIF":1.4,"publicationDate":"2021-06-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46479601","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Optimal human-machine collaboration for enhanced cost-sensitive biometric authentication 优化人机协作，增强对成本敏感的生物特征认证

IF 1.4

SAIEE Africa Research Journal Pub Date : 2021-03-17 DOI: 10.23919/SAIEE.2021.9432899

Johannes Coetzer;Jacques P. Swanepoel;Robert Sabourin

引用次数: 0

Improved Q-learning for Energy Management in a Grid-tied PV Microgrid 用于并网光伏微电网能量管理的改进Q学习

IF 1.4

SAIEE Africa Research Journal Pub Date : 2021-03-17 DOI: 10.23919/SAIEE.2021.9432896

Erick O. Arwa;Komla A. Folly

{"title":"Improved Q-learning for Energy Management in a Grid-tied PV Microgrid","authors":"Erick O. Arwa;Komla A. Folly","doi":"10.23919/SAIEE.2021.9432896","DOIUrl":"10.23919/SAIEE.2021.9432896","url":null,"abstract":"This paper proposes an improved Q-learning method to obtain near-optimal schedules for grid and battery power in a grid-connected electric vehicle charging station for a 24-hour horizon. The charging station is supplied by a solar PV generator with a backup from the utility grid. The grid tariff model is dynamic in line with the smart grid paradigm. First, the mathematical formulation of the problem is developed highlighting each of the cost components considered including battery degradation cost and the real-time tariff for grid power purchase cost. The problem is then formulated as a Markov Decision Process (MDP), i.e., defining each of the parts of a reinforcement learning environment for the charging station’s operation. The MDP is solved using the improved Q-learning algorithm proposed in this paper and the results are compared with the conventional Q-learning method. Specifically, the paper proposes to modify the action-space of a Q-learning algorithm so that each state has just the list of actions that meet a power balance constraint. The Q-table updates are done asynchronously, i.e., the agent does not sweep through the entire state-space in each episode. Simulation results show that the improved Q-learning algorithm returns a 14% lower global cost and achieves higher total rewards than the conventional Q-learning method. Furthermore, it is shown that the improved Q-learning method is more stable in terms of the sensitivity to the learning rate than the conventional Q-learning.","PeriodicalId":42493,"journal":{"name":"SAIEE Africa Research Journal","volume":"112 2","pages":"77-88"},"PeriodicalIF":1.4,"publicationDate":"2021-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.23919/SAIEE.2021.9432896","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45814570","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 4

Iterative Soft-Input Soft-Output Bit-Level Reed-Solomon Decoder Based on Information Set Decoding 基于信息集译码的迭代软输入软输出位级Reed-Solomon译码器

IF 1.4

SAIEE Africa Research Journal Pub Date : 2021-03-17 DOI: 10.23919/SAIEE.2021.9432893

Yuval Genga;Olutayo O. Oyerinde;Jaco Versfeld

{"title":"Iterative Soft-Input Soft-Output Bit-Level Reed-Solomon Decoder Based on Information Set Decoding","authors":"Yuval Genga;Olutayo O. Oyerinde;Jaco Versfeld","doi":"10.23919/SAIEE.2021.9432893","DOIUrl":"10.23919/SAIEE.2021.9432893","url":null,"abstract":"In this paper, a bit-level decoder is presented for soft-input soft-output iterative decoding of Reed-Solomon (RS) codes. The main aim for the development of the proposed algorithm is to reduce the complexity of the decoding process, while yielding a relatively good error correction performance, for the efficient use of RS codes. The decoder utilises information set decoding techniques to reduce the computational complexity cost by lowering the iterative convergence rate during the decoding process. As opposed to most iterative bit-level soft-decision decoders for RS codes, the proposed algorithm is also able to avoid the use of belief propagation in the iterative decoding of the soft bit information, which also contributes to the reduction in the computational complexity cost of the decoding process. The performance of the proposed decoder is investigated when applied to short RS codes. The error correction simulations show the proposed algorithm is able to yield a similar performance to that of the Adaptive Belief Propagation (ABP) algorithm, while being a less complex decoder.","PeriodicalId":42493,"journal":{"name":"SAIEE Africa Research Journal","volume":"112 2","pages":"52-65"},"PeriodicalIF":1.4,"publicationDate":"2021-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.23919/SAIEE.2021.9432893","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43688159","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Copyright 版权

IF 1.4

SAIEE Africa Research Journal Pub Date : 2021-03-17 DOI: 10.23919/SAIEE.2021.9432891

引用次数: 0

Ear-based biometric authentication through the detection of prominent contours 基于耳朵的生物特征认证，通过检测突出的轮廓

IF 1.4

SAIEE Africa Research Journal Pub Date : 2021-03-17 DOI: 10.23919/SAIEE.2021.9432897

Aviwe Kohlakala;Johannes Coetzer

{"title":"Ear-based biometric authentication through the detection of prominent contours","authors":"Aviwe Kohlakala;Johannes Coetzer","doi":"10.23919/SAIEE.2021.9432897","DOIUrl":"10.23919/SAIEE.2021.9432897","url":null,"abstract":"In this paper novel semi-automated and fully automated ear-based biometric authentication systems are proposed. The region of interest (ROI) is manually specified and automatically detected within the context of the semi-automated and fully automated systems, respectively. The automatic detection of the ROI is facilitated by a convolutional neural network (CNN) and morphological postprocessing. The CNN classifies sub-images of the ear in question as either foreground (part of the ear shell) or background (homogeneous skin, hair or jewellery). Prominent contours associated with the folds of the ear shell are detected within the ROI. The discrete Radon transform (DRT) is subsequently applied to the resulting binary contour image for the purpose of feature extraction. Feature matching is achieved by implementing an Euclidean distance measure. A ranking verifier is constructed for the purpose of authentication. In this study experiments are conducted on two independent ear databases, that is (1) the Mathematical Analysis of Images (AMI) ear database and (2) the Indian Institute of Technology (IIT) Delhi ear database. The results are encouraging. Within the context of the proposed semi-automated system, accuracies of 99.20% and 96.06% are reported for the AMI and IIT Delhi ear databases respectively.","PeriodicalId":42493,"journal":{"name":"SAIEE Africa Research Journal","volume":"112 2","pages":"89-98"},"PeriodicalIF":1.4,"publicationDate":"2021-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.23919/SAIEE.2021.9432897","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44417116","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 9

Effect of Graphite Precursor Flake Size on Energy Storage Capabilities of Graphene Oxide Supercapacitors 石墨前驱体薄片尺寸对氧化石墨烯超级电容器储能性能的影响

IF 1.4

SAIEE Africa Research Journal Pub Date : 2021-03-17 DOI: 10.23919/SAIEE.2021.9432895

S. Perumal;A.L.L. Jarvis;M.Z. Gaffoor

引用次数: 2