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Investigating energy policies to boost grid-connected rooftop solar PV in Sudan

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Clean Energy 2023年第5期7卷 994-1005页

作者： Tarig Z.ahmed Ayah Mohamed Mawahib eltayeb ahmed ahmed Osman Elamin Abdalgader Mohamed G.Hassan-Sayed Cambridge Institute for Sustainability Leadership(CISL) University of CambridgeCambridgeCB21QAUK Energy and Climate Change Division Faculty of Engineering and Physical ScienceThe University of SouthamptonSouthamptonSO171BJUK Institute of Engineering Research and Material Technology National Centre for ResearchKhartoumSudan/University of KhartoumSudan University of California Davis1 Shields AveDavisCA 95616USA School of Chemistry Faculty of Engineering and Physical SciencesThe University of SouthamptonSouthamptonSO171BJUK

Grid-connected rooftop solar photovoltaic(PV)systems can reduce the energy demand from the grid and significantly increase the power available to ***,rooftop solar PV has not yet been widely adopted in many sub-Saharan African countries,such as Sudan,although they are endowed with high solar radiation and in dire need of additional *** paper investigates risks and policies to increase grid-connected rooftop solar PV adoption in Sudan.A simplified United Nations Development Program Derisking Renewable Energy Investment framework is adopted to investigate this over three *** Stage 1,a list of risks and barriers was produced based on a literature review of solar PV studies in Sudan and interviews with nine *** was the risk most often mentioned(eight times from nine interviewees),followed by concerns about poor utility grid *** Stage 2,policy de-risking instruments and financial de-risking instruments were listed to overcome the *** include the intro-duction of net metering,the use of a third-party organization to monitor policy implementation,upgrade of the grid infrastructure,public awareness campaigns and energy-saving *** Stage 3,the levelized cost of electricity was estimated for a typical 2-kW rooftop PV system without policies(0.11$/kWh)and with a net-metering policy(0.07$/kWh).

关键词： energy policy rooftop solar PV Sudan energy poverty sustainable development photovoltaics

New Formula for Computing Quaternion Powers

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Applied Mathematics 2022年第3期13卷 282-294页

作者： W. eltayeb ahmed Department of Mathematics and Statistics Faculty of Science Imam Mohammad Ibn Saud Islamic University Riyadh Saudi Arabia Department of Basics and Engineering Sciences Faculty of Engineering University of Khartoum Khartoum Sudan

In this work, we create a new mathematical formula that computes the power of a quaternion number raised to a positive integer by reducing the real matrix of order 4 × 4 that we take to represent this quaternion number to a matrix that makes the process of multiplying this quaternion number by itself simpler. We also present a new method for computing the power of a real matrix of order 2 × 2 as an application of this formula.

关键词： Quaternions Matrix Algebra Kayley-Dickson Construction

A Modern Method for Constructing the S-Box of Advanced Encryption Standard

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Applied Mathematics 2019年第4期10卷 234-244页

作者： W. eltayeb ahmed Mathematics and Statistics Department Faculty of Science Imam Mohammad Ibn Saud Islamic University Riyadh KSA Department of Basics and Engineering Sciences Faculty of Engineering University of Khartoum Khartoum Sudan

The substitution table (S-Box) of Advanced Encryption Standard (AES) and its properties are key elements in cryptanalysis ciphering. We aim here to propose a straightforward method for the non-linear transformation of AES S-Box construction. The method reduces the steps needed to compute the multiplicative inverse, and computes the matrices multiplication used in this transformation, without a need to use the characteristic matrix, and the result is a modern method constructing the S-Box.

关键词： Advanced Encryption Standard S-Box Extended Euclidean Algorithm Greatest Common Divisor XOR Operation

On Rijndael ByteSub Transformation

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Applied Mathematics 2019年第3期10卷 113-118页

The first step in converting a plaintext to ciphertext by the famous Advanced Encryption Standard (AES), which is called Rijndael ByteSub Transformation, involves some operations: computing a multiplicative inverse, multiplying this multiplicative inverse by a specific matrix, and adding the result to a specific vector. The purpose of this research is to simplify these operations. This paper gives elegant techniques and presents the matrices multiplication as simple XOR operations, and the result is a simple, straightforward way finding the transformation.

关键词： Rijndael Cipher Advanced Encryption Standard Multiplicative Inverse XOR Operation

主动/半主动悬架的LQR与模糊控制方法比较研究

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主动/半主动悬架的LQR与模糊控制方法比较研究

作者： ahmed Elawad eltayeb ahmed 吉林大学

学位级别：硕士

本文的主题是在所有可能的形式中研究车辆主动悬架系统的控制性能。悬架系统是汽车设计的重要方面,悬架系统的性能直接关系到汽车的操纵稳定性与驾驶者与乘客的乘坐舒适性。很多设计者都愿意投入时间和金钱来提升悬架系统的性能。悬架... 详细信息

本文的主题是在所有可能的形式中研究车辆主动悬架系统的控制性能。悬架系统是汽车设计的重要方面,悬架系统的性能直接关系到汽车的操纵稳定性与驾驶者与乘客的乘坐舒适性。很多设计者都愿意投入时间和金钱来提升悬架系统的性能。悬架系统分为被动、半主动和主动悬架系统三种类型。被动悬架是具有固定阻尼和刚度的纯机械结构。半主动悬架具有可变的阻尼系数和固定刚度,它的阻尼值可以通过控制系统来改变并实现理想的控制性能。但是大多先进的系统都是用主动悬架,它多出一个可以增加和消耗能量的作动器部分。作动器由简单或复杂的控制系统控制,其与电子电路连接产生理想的致动控制。研究者想要控制悬架系统就必须了解车身和它的所有相关模型。所以本文第一部分建立一个数学模型是非常重要的,本文建立了四分之一车身模型,因为四分之一模型是最简单的最基本的模型,只有一个自由度。本文的第二部分是优化数学模型。数学优化是在一些有效可行的办法中根据相关的评价标准选出最好的方法。本文利用数学模型通过最小目标函数,并设置合适的权重函数,使用LQR优化算法找到控制器最优参数。通过LQR优化找到了优化的被动悬架刚度系数和阻尼系数、优化的半主动悬架阻尼控制率和优化的主动悬架控制率。用优化的方法控制悬架系统。目前世界上有很多学者都致力于研究主动悬架控制方法。文章最后一部分比较了半主动悬架和主动悬架在使用LQR控制和模糊逻辑控制的性能特点。本文使用基本的,经典的模糊控制方法来控制主动悬架系统,然后利用Matlab中的simulink工具进行LQR和模糊控制下悬架的性能分析,包括悬架位移、轮胎动挠度和控制器信号。最后得出结论,现代模糊控制器相比LQR控制器有明显的优越性。简单地说,本文给出了汽车悬架系统的相关知识,给出了车身四分之一数学模型,悬架系统的数学优化方法和在被动、半主动和主动系统下车身与轮胎的响应分析。然后通过比较证明了主动悬架系统比被动和半主动系统更加优越。无论在半主动悬架系统还是主动悬架系统中,使用模糊控制器和LQR控制器均具有明显的优势。

关键词：主动悬架系统半主动悬架系统 LQR控制方法模糊逻辑控制方法汽车动力学

Comprehensive literature review on the radiographic findings, imaging modalities, and the role of radiology in the COVID-19 pandemic

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World Journal of Radiology 2021年第9期13卷 258-282页

作者： Aman Pal Abulhassan Ali Timothy R Young Juan Oostenbrink Akul Prabhakar Amogh Prabhakar Nina Deacon Amar Arnold ahmed eltayeb Charles Yap David M Young Alan Tang Subramanian Lakshmanan Ying Yi Lim Martha Pokarowski Pramath Kakodkar School of Medicine National University of Ireland GalwayGalway H91 TK33GalwayIreland Department of Computer Science Yale UniversityNew HavenCO 06520United States Department of Health Science Duke UniversityDurhamNC 27708United States The Hospital for Sick Kids University of TorontoToronto M5SOntarioCanada

Since the outbreak of the coronavirus disease 2019(COVID-19)pandemic,over 103214008 cases have been reported,with more than 2231158 deaths as of January 31,*** the gold standard for diagnosis of this disease remains the reverse-transcription polymerase chain reaction of nasopharyngeal and oropharyngeal swabs,its false-negative rates have ignited the use of medical imaging as an important adjunct or *** imaging assists in identifying the pathogenesis,the degree of pulmonary damage,and the characteristic features in each imaging *** literature review collates the characteristic radiographic findings of COVID-19 in various imaging modalities while keeping the preliminary focus on chest radiography,computed tomography(CT),and ultrasound *** the higher sensitivity and greater proficiency in detecting characteristic findings during the early stages,CT scans are more reliable in diagnosis and serve as a practical method in following up the disease time *** research rapidly expands,we have emphasized the CO-RADS classification system as a tool to aid in communicating the likelihood of COVID-19 suspicion among healthcare ***,the utilization of other scoring systems such as MuLBSTA,Radiological Assessment of Lung Edema,and Brixia in this pandemic are reviewed as they integrate the radiographic findings into an objective scoring system to risk stratify the patients and predict the severity of ***,current progress in the utilization of artificial intelligence via radiomics is ***,the lesson from the first wave and preparation for the second wave from the point of view of radiology are summarized.

关键词： Coronavirus COVID-19 Computed tomography Ultrasound MuLBSTA Scoring system Radiological Assessment of Lung Edema classification Brixia score

Determinations of Amino Acids and Fatty Acids Levels in Date Palm Kernel Flour in Sudan

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Journal of Agricultural Science and Technology(A) 2020年第5期10卷 283-289页

作者： Rehab Salih Mahmoud Abdalla Mohammed ahmed Hassan eltayeb Ammar Mohammed Elamin Hassan Abdelrahim Mohamed El Hussein Sudanese Nuclear and Radiological Regulatory Authority Ministry of Higher Education and Scientific ResearchKhartoum 11111Sudan Sudan Academy of Sciences Ministry of Higher Education and Scientific ResearchKhartoum 11111Sudan Sudan Atomic Energy Commission Ministry of Higher Education and Scientific ResearchKhartoum 11111Sudan Central Laboratory Ministry of Higher Education and Scientific ResearchKhartoum 11111Sudan

The aim of this study was the determination of various levels in date palm kernel(DPK)flour for enhancing production performance of animals natural feed in Sudan,in addition to protecting the environment from *** material used is flour of date seeds from the following date varieties:Berkawi,Gandilla,Tamouda,Klmah,Mashreq Wad Khatib,Mashreq Wad *** research was conducted at the following institutions:Geological Research Authority of Sudan,preparation of the DPK;Institute Penyelidikan Produk Halal of University Putra Malaysia,determination of amino acids using high performance liquid chromatography mass spectroscopy mass spectroscopy(HPLC MSMS)fluorescence;University of Medical Sciences and Technology-Sudan,determination of fatty acids using gas chromatography-mass spectrometry(GC-MS).Seeds were collected from various areas of Sudan and from *** seeds were mixed together and they weigh 8 *** preparation includes five steps,namely(1)washing,(2)soaking,(3)flushing,(4)drying,(5)*** flour was then used to determine its contents of amino acids by high performance liquid chromatography-fluorescence detector(HPLC-FLD)and fatty acids by *** of the following amino acids were determined in the sample(percentages in w/w are indicated between parenthesis):hydroxyprofine(0.224),aspartic acid(7.029),serine(6.350),glutamic acid(1.745),glycine(3.183),histicline(0.705),arginine(7.262),threonine(ND),alanine(15.558),proline(4.302),cysteine(34.326),tyrosine(2.070),voline(0.402),methionine(2.989),lysine(4.723),isoleucine(2.203),leucine(4.485),phenylalanine(2.442)while the determined fatty acids are:lauric acid(11.765),tetradecanoic acid(14.214),methyl palmitoleate(16.235),palmitic acid(16.431),cis-10-Heptadecenoic acid,methyl ester(17.253),margaric acid(17.464),linoleic acid(18.183),oleic acid(18.236),stearic acid(18.449),methyl ester(20.106)and arachidic acid(20.308).The seeds of the dates are found to be rich in amino acids as well a

关键词： DPK solid waste nutritional value amino acids fatty acids

Diagnosing Breast Cancer Accurately Based on Weighting of HeterogeneousClassification Sub-Models

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Computer Systems Science & Engineering 2022年第9期42卷 1257-1272页

作者： Majdy Mohamed eltayeb Eltahir Tarig Mohammed ahmed Department of Information Systems College of Science&Arts at MahayilKing Khalid UniversityMuhayel Aseer62529Kingdom of Saudi Arabia Department of Information Technology Faculty of Computing and Information TechnologyKing Abdul-Aziz UniversityJeddah21589Kingdom of Saudi Arabia Department of Computer Sciences Faculty of Mathematical Sciences and InformaticsUniversity of KhartoumKhartoum11115Sudan

In developed and developing countries, breast cancer is one of the leading forms of cancer affecting women alike. As a consequence of growing lifeexpectancy, increasing urbanization and embracing Western lifestyles, the highprevalence of this cancer is noted in the developed world. This paper aims todevelop a novel model that diagnoses Breast Cancer by using heterogeneous datasets. The model can work as a strong decision support system to help doctors tomake the right decision in diagnosing breast cancer patients. The proposed modelis based on three datasets to develop three sub-models. Each sub-model worksindependently. The final diagnosis decision is taken by the three sub-models independently. The power of the model comes from the diversity checks of patientsand this reduces the risk of wrong diagnosing. The model has been developedby conducting intensive experiments. Several classification algorithms were usedto select the best one in each sub-model. As the final results, the sub-modelaccuracies were 72%, 74% and 97%.

关键词： Breast cancer data mining classification

Epidemiology of schistosomiasis in Gezira area Central Sudan and analysis of cytokine profiles

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Asian Pacific Journal of Tropical Medicine 2013年第2期6卷 141-147页

作者： Nagla Mustafa eltayeb Moawia Mohamed Mukhtar ahmed Babiker Mohamed Department of Immunology and Biotechnology Tropical Medicine Research InstituteNational Centre for ResearchKhartoumSudan Department of Immunology Institute of Endemic DiseasesUniversity of KhartoumKhartoumSudan National Centre for Research Ministry of Science and TechnologyKhartoumSudan

Objective:To determine and compare anti-schistosoma IgC,interleukin-10(IL-10) and interferon-γ(IFN-γ)levels in the serum of patients and endemic controls and to investigate the epidemiological situation of Al-Hebaika village in the northern part of Gezira Agricultural Irrigation Scheme in ***:During 2005 survey,serum were collected from 118 *** eight were parasitological positive(patients),and 50 were negative(endemic controls).Indirect ELISA was used to measure and compare the levels of immunoglobulin C(IgC) against Schistsoma mansoni(***) soluble worm antigen(SWA) in the patients and endemic control groups from the village and compared with 20 healthy non endemic *** ELJSA was also used to measure and compare IL-10 and IFN-γin the serum of the selected ***:The overall prevalence of *** was 20.0%and 0.9%in the first and the second surveys respectively,while the intensity of infection was the same in the two surveys 1.38[geometric mean egg count(GMFC)].The overall prevalence of *** infection was 68.5% and 15.4%,while the intensity of infection was 2.75(GMEC) and 1.70(GMEC) in the two surveys *** reactivity against SWA showed no significant difference between Schistosoma positive patients and endemic ***,there were high significant differences between each of these two groups and the non endemic control group(P= 0,000).Schistosoma patients and exposed controls had significantly higher IL-10 concentration compared with non endemic *** endemic controls showed significantly higher IFN-γconcentration than patients(P = 0.000).Also there was very significant difference between IFN-γlevels of each of patients endemic controls and that of the non endemic controls(P = 0.003).Conclusions:The study concluded that IFN-γhas a role in the natural resistant to schistosoma mansoni infection. The prevalence and intensity of *** in the Gezira Irrigation Scheme was greatly red

关键词： Schistosomiasis IgG IL-10 IFN-gama ELISA