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SSRN 2024年

作者： Firdissa, Benti Degefa, Sileshi Mulugeta, Eyobel Sithole, Dingane Environmental Protection Authority Addis Ababa Ethiopia Center for environmental science Collage of Natural and computational Sciences Addis Ababa university Addis Ababa Ethiopia Addis Ababa University Ethiopia Bees Consultancy Ethiopia

Cement, vital for global construction, faces challenges in accurately quantifying CO2 emissions in Ethiopia. Discrepancies arise from country-specific factors, statistical variations, and data challenges. This study stresses emission factors (EFs) and the imperative of defining CO2 accounting boundaries. To overcome issues, factory-level measurements for diverse clinker and cement production were conducted through on-site surveys. Utilizing IPCC standards, results reveal overestimations in earlier assessments due to specific CO2 emission factors, unaddressed technological transitions, and neglected clinker-to-cement ratios. The study underscores the necessity for precise CO2 assessments, emphasizing refined methodologies for informed policy decisions and sustainable practices in the global construction sector. © 2024, The Authors. All rights reserved.

关键词： Cements

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Gis-Based Statistical Analysis for Landslide Susceptibility Evaluation and Zonation Mapping: A Case from Blue Nile Gorge, Gohatsion-Dejen Road Corridor, Central Ethiopia

SSRN

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SSRN 2024年

作者： Ali, Yechale Gugsa, Trufat Hailemariam Raghuvanshi, Tarun Kumar School of Earth Science College of Natural and Computational Sciences Addis Ababa University PO Box 1176 Addis Ababa Ethiopia

The study was conducted in the Blue Nile Gorge in Central Ethiopia, about 185 km from addis-ababa, along the Gohatsion-Dejen road corridor. Landslides have often occurred in this area. The objective of the study was to evaluate the susceptibility of the area to landslides and to prepare a landslide susceptibility zoning (LSZ) map. The study used a statistical information value (IV) model that took into account various factors including slope material, elevation, slope, aspect, land-use and land cover, proximity to road, and proximity to streams. Each of these factors was classified based on different conditions like landslide concentration, topography, geology, and land-use and land-cover types. The landslide inventory mapping was conducted through field observations and Google Earth image interpretation. The study then used the influence of each causative factor on past landslides to calculate their respective IVs. The statistical IVs were then used to evaluate the landslide susceptibility. The LSZ map produced from this study shows that 22.3% of the study area is at very high hazard, 23.1% at high hazard, 18.8% at moderate hazard, 23.1% at low hazard, and 12.8% at low susceptibility. The LSZ map was validated using the Receiver Operating Characteristics Curve (ROC), landslide density index (LDI), and past landslide data, which showed acceptable results. The prepared LSZ map can be used for safe land-use planning of the ***/phrasesBlue Nile Gorge, Landslide, Landslide Susceptibility, Landslide susceptibility index, Statistical Information Value Model, © 2024, The Authors. All rights reserved.

关键词： Landslides

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Seepage modeling approaches in the dam site and through the dam body: a review

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Arabian Journal of Geosciences 2023年第1期17卷 1-20页

作者： Misgana, Kassahun Meten, Matebie Department of Geology College of Natural and Applied Sciences Addis Ababa Science and Technology University Addis Ababa Ethiopia Department of Geology College of Natural and Computational Science Dilla University Dilla Ethiopia Mineral Exploration Exploitation and Processing Center of Excellence Addis Ababa Science and Technology University Addis Ababa Ethiopia

Seepage flow through pervious media or formations is one of the causative factors for dam failure. In order to reduce and control this problem, seepage modeling and analysis are very important. The main aim of this article is to present the comprehensive review on various modeling approaches and methods available for seepage evaluation through or beneath dam. Furthermore, an attempt is also made to assess the application and effectiveness of these techniques in dam seepage modeling and analysis. Moreover, case studies of dam seepage analysis in Ethiopia were also reviewed. For a century, various techniques have been developed that can be used to study the seepage cases of hydraulic structures including dams. Broadly, these techniques can be categorized in to continuum and discontinuum seepage modeling approaches. Continuum approach includes pore-network model, whereas discontinuum approach includes equivalent continuum, discrete fracture network, dual-porosity, and triple-porosity models. Each of these approaches may consider different causative factors and utilizes various methods for seepage analysis. The experimental, analytical, and numerical methods are commonly used in the modeling approaches based on Darcian and non-Darcian laws. The selection of appropriate modeling approaches depends on various factors and considerations including the spatial and temporal scale of flow regime, material type and properties, dam width and height, water level, availability of data, and modeler’s skill. In comparison, each of these models has its own advantages and disadvantages over the other.

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Effects of landscape positions on soil physicochemical properties at Shenkolla Watershed, South Central Ethiopia

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Environmental Systems Research 2021年第1期10卷 1-15页

作者： Bufebo, Belayneh Elias, Eyasu Agegnehu, Getachew Department of Natural Resource Management Wachemo University Hosanna Ethiopia Center for Environmental Science College of Natural and Computational Sciences Addis Ababa University Addis Ababa Ethiopia Ethiopian Institute of Agricultural Research Addis Ababa Ethiopia

Background: Understanding the effects of landscape positions on soil physicochemical properties is crucial for improving the soil productivity and to ensure the environmental sustainability. Three land use types forest land, grazing land and cultivated land all within upper, middle and lower landscape positions were selected to determine the effects of landscape positions, land use types and their interaction effects on soil physicochemical properties. Twenty seven soil samples were collected from lower landscape, middle landscape and upper landscape positions at the depth of 0–20 cm in nine replications. In addition, undisturbed soil samples were taken using core sampler from each land use type under upper, middle and lower landscape positions for the ascertainment of bulk density and water retentive capacity. The analysis of variance (ANOVA) was applied to determine variations in soil parameters among landscape positions and land use types. A Generalized Linear Models (GLMs) analysis was conducted to determine the influence of independent (fixed) factors, on the soil properties (response variables). Treatment means comparison was determined using the Least Significant Difference (LSD) at 0.05 level of significances. Results: The result indicated that among the soil properties sand (p © The Author(s) 2021.

关键词： Physicochemical properties

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Improving wind speed forecasting at Adama wind farm II in Ethiopia through deep learning algorithms

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Case Studies in Chemical and Environmental Engineering 2024年 9卷

作者： Chaka, Mesfin Diro Semie, addisu Gezahegn Mekonnen, Yedilfana Setarge Geffe, Chernet Amente Kebede, Hailemichael Mersha, Yonas Anose, Fikru Abiko Benti, Natei Ermias Computational Data Science Program College of Natural and Computational Sciences Addis Ababa University P. O. Box 1176 Addis Ababa Ethiopia Center for Environmental Science College of Natural and Computational Sciences Addis Ababa University P. O. Box 1176 Addis Ababa Ethiopia Department of Physics College of Natural and Computational Sciences Addis Ababa University P.O. Box 1176 Addis Ababa Ethiopia Ethiopian Institute of Water Resources (EIWR) Addis Ababa University (AAU) Addis Ababa Ethiopia Department of Physics College of Natural and Computational Sciences Wolkite University Ethiopia

Wind power plays a critical role in supporting Ethiopia's electricity generation, particularly during dry seasons when hydropower availability diminishes. This contribution becomes even more crucial for sustaining industrial growth. However, accurately estimating wind energy remains challenging due to its random and highly variable nature. Deep learning models for time series prediction have been employed to address this issue, and this study evaluates the effectiveness of long short-term memory (LSTM) and gated recurrent unit (GRU) models in predicting wind speed at Adama Wind Farm II in Ethiopia. Model performance was assessed using R², RMSE, and MAE. GRU significantly outperformed LSTM across all metrics and forecasting horizons. For daily forecasting, GRU achieved an R² of 0.9727, exceeding LSTM's 0.9062 by 7.34 %, with corresponding RMSE values of 0.0005 and 0.0018, respectively. Similarly, GRU surpassed LSTM's performance for weekly and monthly forecasting. In weekly forecasting, GRU achieved an R² of 0.9969 compared to LSTM's 0.9930, with RMSE values of 0.0001 for both models. For monthly forecasting, GRU achieved an R² of 0.9330 compared to LSTM's 0.9303, with corresponding RMSE values of 0.0019 for both models. MAE values also followed the same pattern, with GRU consistently demonstrating lower values than LSTM across all forecasting horizons. These findings advance renewable energy and wind power forecasting research, highlighting the adaptability and versatility of LSTM and GRU models for capturing wind behavior. Decision-makers can use these findings to optimize wind power production, enhance grid operation efficiency, and promote sustainable and cost-effective wind energy. LSTM and GRU models have emerged as powerful tools for precise wind speed and wind power forecasting, which are essential for modern wind energy planning systems. They lay the foundation for a more environmentally friendly and sustainable en

关键词： Adama wind farm II Deep learning Ethiopia LSTM and GRU models Renewable energy Wind speed forecasting

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Cytotoxic and other bioactivities of a novel and known sesquiterpene lactones isolated from Vernonia leopoldi (Sch. Bip. ex Walp.) Vatke in breast cancer cell lines

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Toxicology Reports 2022年 9卷 382-392页

作者： Tuasha, Nigatu Escobar, Zilma Seifu, Daniel Gadisa, Endalamaw Petros, Beyene Sterner, Olov Oredsson, Stina Department of Biology Hawassa College of Teacher Education Sidaama National Regional State Hawassa Ethiopia Department of Microbial Cellular and Molecular Biology College of Natural and Computational Sciences Addis Ababa University Addis Ababa Ethiopia Centre for Analysis and Synthesis Faculty of Science Lund University Lund Sweden Department of Biochemistry School of Medicine College of Health Sciences Addis Ababa University Addis Ababa Ethiopia Armauer Hansen Research Institute (AHRI) Addis Ababa Ethiopia Department of Biology Faculty of Natural Science Lund University Lund Sweden

Vernonia leopoldi (Sch. Bip. ex Walp.) Vatke (Asteraceae) is one of the widely used anti-cancer traditional medicinal plants in Ethiopia, despite the lack of data to support its therapeutic efficacy. Here we describe the isolation of compounds from the plant and the investigation of their cytotoxicity and other bioactivities. We identified the novel sesquiterpene lactone (SL) 11ß,13-dihydrovernodalol along with the three other SLs (vernomenin, vernolepin, and 11ß,13-dihydrovernodalin) and three flavonoids (apigenin, eriodyctiol, and luteolin) isolated from this plant for the first time. The structures of all the compounds were established based on extensive analysis of nuclear magnetic resonance spectroscopic data and confirmed by high-resolution electrospray ionization mass spectrometry. We then studied the biological activities of the SLs and found that all were cytotoxic at low μM ranges against MCF-7 and JIMT-1 breast cancer cells as well as against the normal-like MCF-10A breast epithelial cells evaluated in a spectrophotometric assay. All the SLs significantly reduced JIMT-1 cell migration after 72 h of treatment with 2 μM concentrations in a wound healing assay. Treatment with all SLs reduced the aldehyde dehydrogenase expressing cancer stem cell sub-population of the JIMT-1 cells significantly, evaluated by flow cytometry. Only 11ß,13-dihydrovernodalin resulted in a significant inhibition of tumor necrosis factor-α-induced translocation of nuclear factor κB to the cell nucleus. In addition, we show that the reporter fluorophore nitrobenzoxadiazole (NBD) can successfully be conjugated with an SL and that this SL-NBD conjugate is taken up efficiently in JIMT-1 cells. Therefore, the overall bioactivities of the SL compounds and specifically their effects against the stemness of breast cancer cells make them prime candidates for further in-depth investigation. © 2022

关键词： Cancer stem cells Isolation of anti-cancer bioactive compounds Novel sesquiterpene lactone Traditional medicine Vernonia leopoldi

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Automatic Identification of Teff (Eragrostis Tef) Flour Adulteration Using Machine Learning

Automatic Identification of Teff (Eragrostis Tef) Flour Adul...

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International Conference on Systems and Informatics (ICSAI)

作者： Zekiyos Abayneh Bochera Solomon Gizaw Onime Clement Dept. of Computational Data Science Addis Ababa University Addis Ababa Ethiopia Dept. of Computer Science Addis Ababa University Addis Ababa Ethiopia Information and Communication Technology Section (ICTS) Abdus Salam International Centre for Theoretical Physics (ICTP) Trieste Italy

ISBN: (数字)9798331510138

ISBN: (纸本)9798331510145

Food adulteration, the act of mixing foodstuffs with lower-quality foodstuffs or other food and non-food items, has become a global issue, particularly in developing countries like Ethiopia. This is a significant problem as it can lead to nutritional deficiencies and in some cases, illnesses, diseases or even death. The identification of adulterated food typically requires physio-chemical laboratory tests that vary depending on the type and level of adulterant. Teff flour, a daily staple food in Ethiopia, is often adulterated with wood flour and gypsum powder. In this research work, we utilized computer vision techniques to extract textural and color features from images of both adulterated and pure Teff flour. We then trained a Support Vector Machine (SVM) based machine learning model to identify adulterated Teff flour and predict the level of adulteration. The presented results show varying levels of prediction accuracy depending on the type of Teff flour, the level of adulteration. The developed model was also found to provide good results with images sizes ranging from $\boldsymbol{128 \times 128}$ to $\boldsymbol{2048 \times 2048}$ pixels. The results show overall model accuracy was above 90% when the adulteration level of red Teff flour is more than 25% and above 84% when the adulteration level of white wood flour was above 25%.

关键词： Support vector machines Computer vision Accuracy Powders Machine learning algorithms Image color analysis computational modeling Feature extraction Convolutional neural networks Testing

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Abattoir Site Suitability Modeling Using a Geographic Information System and Multi-Criteria Evaluation–A Case Study of Dire Dawa City, Ethiopia

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KN - Journal of Cartography and Geographic Information 2023年第2期73卷 161-178页

作者： Yasin, Kalid Hassen Weldemariam, Elias Cherenet Woldemariam, Gezahegn Weldu Gelete, Tadele Bedo Yuya, Iman Abdella Geo-Information Science Program School of Geography and Environmental Studies Haramaya University P. O. Box138 Dire Dawa 3220 Ethiopia Department of Remote Sensing and Application Research and Development Space Science and Geospatial Institute Entoto Observatory and Research Center (EORC) P.O. Box 33679 Addis Ababa Ethiopia Addis Ababa University P.O. Box 1176 Addis Ababa Ethiopia GIS and Remote Sensing Program DepartmentofGeographyandEnvironmentalStudies Dire Dawa University P.O. Box 1362 Dire Dawa Ethiopia

An abattoir is an essential urban plant that provides services to the community by slaughtering animals, examining, and certifying carcasses, and transporting them to butchers in a residential area hygienically. However, development activities, rapid population growth, and expansion of urban and industrial areas have caused abattoirs to face environmental hazards induced by some neighboring practices;this condition is often the same or worse within and nearby areas of some municipal abattoirs in Ethiopia. The objective of this study was to model and identify the suitable locations with the utmost potential to contribute to the establishment of environmentally sound, socially acceptable, and economically feasible abattoirs in Dire Dawa City, Ethiopia. We applied an integrated modeling approach using an automated Geographic Information Systems (GIS) with Multi-Criteria evaluation (MCE) and the Analytic Hierarchy Process (AHP). The criteria evaluation for suitable site identification and mapping was based on experts' references accompanied by 14 environmental and socioeconomic factors— topographic features (elevation and slopes), land use and land cover, wind direction, solar radiation, and proximity to roads, railways, industrial sites, social services, hydrowells, bus stations, high-tension lines, distance from the airport, and streams—adopted from literature and generated from open-source data. The abattoir suitability map was produced using a linear combination operation after individual factors were weighted and reclassified to a standard scale divided into four classes ranging from restricted to highly suitable. Based on the applied methods, the analysis results revealed that 14.33% of the area was highly suitable, 43.67% moderately to less suitable, and 42% restricted. Moreover, the optimal candidate site for abattoir development with good access to roads and railways covering an area of 1 km² has been found in the northern part of the city. Hence, mu

关键词： Abattoirs AHP Dire Dawa City GIS Land suitability analysis Multi-Criteria Evaluation

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Seismic hazard evaluation using site response analysis and amplitude parameters at Hawassa town, Main Ethiopian Rift

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Arabian Journal of Geosciences 2023年第3期16卷 1-22页

作者： Ayele, Alemayehu Woldearegay, Kifle Meten, Matebie Department of Geology College of Applied Science Addis Ababa Science and Technology University Addis Ababa Ethiopia Department of Geology College of Natural and Computational Science Wachamo University Hosanna Ethiopia School of Earth Science Mekelle University Mekelle Ethiopia

Ground motion from an earthquake is the most devastating geo-hazard in seismically active areas as it affects human life and infrastructure as well as their day-to-day activities. Hawassa town has faced distress of building due to earthquake of small to intermediate magnitudes. The main aim of this study is to predict ground motion parameters using DEEPSOILV.7 program. For this purpose, linear, equivalent linear, and nonlinear approaches at five sites were applied. In this study, the natural period (T30) and amplification (A30) of the site were used to determine the amplification. Two input ground motions from the DEEPSOILV.7 software were used to generate site’s PGA (g), spectral acceleration (PSA) (g), maximum strain (%), and amplification factor (AF) at the surface. In addition, T30 and A30 maps at a depth of 30 m were prepared by krigging interpolation techniques. The PGA (g), AF, and maximum strain (%) and PSA (g) showed the amplification at a shallow depth for the input motion at four sites but deamplification at one sites. The highest maximum strain (%) values were observed at a shallow depth indicating the probability of liquefaction induced ground deformation. The T30 and A30 map showed a long period and high amplification in the northern part but a short period and low amplification in the southern part. The results of this study will be used at local, zonal, regional, and federal levels for the design of critical structures as it provides first-hand information on the seismic hazard of the area.

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Metric ideals and its Structures in AL-monoids

arXiv

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arXiv 2024年

作者： Regasa Ashale, Tekalign Aklilu Abebe, Girum Venkateswarlu, Kolluru Department of Mathematics College of Natural and Computational Science College Addis Ababa University Addis Ababa Ethiopia Department of Computer Science and System Engineering College of Engineering Andhra University AP Visakhapatanam India

This paper introduces the concept of metric ideals in AL-monoids. We also examine the structure of AL-monoids and describe some of the properties of homomorphism and fundamentalisomorphism *** we introduce and examine... 详细信息

关键词： Algebra

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