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Conventional generation emulation for power grids with a high penetration of wind power

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Clean Energy 2021年第1期5卷 93-103页

作者： rasha el-azab Eslam M.Wazeer Mohamed Daowd A.M.Abdel Ghany electrical Power and Machines Department Faculty of EngineeringHelwan UniversityCairoEgypt

Integrating large-scale wind plants with the electricity grids has many challenges for grid *** the variability and uncertainty of wind power,coordinating between different technologies of generation in the same grid can be considered the main problem,specifically for short-term frequency ***,a large penetration of wind power generation in modern power grids has a risky influence on the power-system ***-generation plants have contradictory behaviour compared to classic thermal plants,especially in active generated power-shortage events due to the variable nature of wind *** experience in wind plants keeps part of the available wind power unloaded,using what are known as deloading *** deloading techniques are usually applied to emulate the thermal-plant-governor function and confirm a proper spinning reserve for any active-power *** techniques decrease the generated power from wind plants continuously from maximum point tracking ***,the practical capacity,annual generated energy and economical income of wind plants are *** addition,grid-protection and control sub-schemes are set and designed according to the well-known conventional responses of thermal plants,which increase the need for thermal-plant-behaviour *** this paper,instead of the usual deloading methods,a supercapacitors scheme is proposed with wind turbines to emulate the response of conventional power *** study discusses the technical and economic benefits of the proposed addition of supercapacitors in the wind-plant-planning *** frequency grid-code indices are selected to evaluate studied *** results of the IEEE four-generation two-area system determines the effectiveness of suggested schemes *** System Advisor Model(SAM)program estimates the economic benefits of a typical US study case compared with the existing wind-deloading technique.

关键词： wind energy planning analysis energy storage supercapacitor frequency stability

Arrhythmia Detection by Using Chaos Theory with Machine Learning Algorithms

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Computers, Materials & Continua 2024年第6期79卷 3855-3875页

作者： Maie Aboghazalah Passent el-kafrawy Abdelmoty M.Ahmed rasha elnemr Belgacem Bouallegue Ayman el-sayed Math and Computer Science Department Faculty of ScienceMenoufia UniversityShebin El-komEgypt College of Engineering Computer Science DepartmentEffat UniversityJeddahKingdom of Saudi Arabia Department of Computer Engineering College of Computer ScienceKing Khalid UniversityAbha61421Saudi Arabia Computer Science and Engineering Department Faculty of Electronic EngineeringMenoufia UniversityShebin El-komEgypt Climate Change Information Center and Expert Systems Agriculture Research CenterGizaEgypt

Heart monitoring improves life ***(ECGs or EKGs)detect heart *** learning algorithms can create a few ECG diagnosis processing *** first method uses raw ECG and time-series *** second method classifies the ECG by patient *** third technique translates ECG impulses into Q waves,R waves and S waves(QRS)features using richer *** ECG signals vary naturally between humans and activities,we will combine the three feature selection methods to improve classification accuracy and *** using all three approaches have not been examined till *** researchers found that Machine Learning(ML)techniques can improve ECG *** study will compare popular machine learning techniques to evaluate ECG *** algorithms—Support Vector Machine(SVM),Decision Tree,Naive Bayes,and Neural Network—compare categorization *** plus prior knowledge has the highest accuracy(99%)of the four ML *** characteristics failed to identify signals without chaos *** 99.8%classification accuracy,the Decision Tree technique outperformed all previous experiments.

关键词： ECG extraction ECG leads time series prior knowledge and arrhythmia chaos theory QRS complex analysis machine learning ECG classification

Prophylactic effect of vitamin E against hepatotoxicity,nephrotoxicity,haematological indices and histopathology induced by diazinon insecticide in mice

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Current Zoology 2009年第3期55卷 219-226页

作者： Nahla S.el-SHENAWY rasha A.AL-EISA Fawzia el-SALMY Omema SALAH Biology Department Faculty of ScienceTaif UniversityKingdom of Saudi Arabia

Considering that the involvement of reactive oxygen species （ROS） has been implicated in the toxicity of various pesticides, this study was designed to study the ameliorative effect of Vitamin E （100 mg/kg body weight） on mice （25 -30 mg） treated with diazinon （32.5 or 16.25 mg/kg body weight） organophosphate insecticide for 14 days. Subehronic DZN exposure and the protective effects of vitamins E （vitE） were evaluated for their effects on haematological indices, the enzymes concerning liver damage [plasma alanine aminotransferase （ ALT）, aspartate aminotaransferase （ AST）, alkaline phosphatise （ ALP）, and some parameters of kidney function （urea and creatinine） in mice. Additionally, the histopathological changes in liver and kidney tissue were examined. The high dose of diazinon （DZNH） decreased the body weight significantly at the end of experiment. Additionally, the liver and kidney were examines for histopathological changes. The high dose of diazinon decreased body weight significandy. Moreover, there was a statistically significant decrease in haemoglobin （Hb）, red blood cell （RBC） and hematocrit （Hct） in diazinon-treated mice compared to controls. This decrease was partially remedied in the diazinon-treated group that also received vitE. Damage in the liver and kidney tissues was also evident as elevated plasma ALT, AST, ALP, urea and creatinine. VitE partially counteracts the toxic effect of DZN and repairs tissue damage in the liver and kidney, especially when supplemented to 1/4 LD50 intoxicated animals. Histopathological changes in liver and kidney were observed only in 32.5 mg/kg DZN given group. These results suggest that the effects of DZN are dose dependent. No pathological findings were observed in vitE ＋ DZNtreated groups. According to the present study, we conclude that vitE ean reduce the detrimental impacts of diazinon on haematological indicies, as well as liver and kidney function [ Current Zoology 55 （3）： 219 - 226, 2009].

关键词： Organophosphorus insecticide Alanine aminotransferase (ALT) Aspartate aminotransferase (AST) Albumin Urea Creatinine Histopathology

Enhancing Task Assignment in Crowdsensing Systems Based on Sensing Intervals and Location

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Computers, Materials & Continua 2022年第6期71卷 5619-5638页

作者： rasha Sleem Nagham Mekky Shaker el-Sappagh Louai Alarabi Noha AHikal Mohammed elmogy Faculty of Computers and Information Mansoura UniversityMansoura35516Egypt Faculty of Computers and Artificial Intelligence Benha UniversityBanha13518Egypt Faculty of Computer Science and Engineering Galala UniversitySuez435611Egypt College of Computer and Information Systems Umm Al-Qura UniversityMecca715Saudi Arabia

The popularity of mobile devices with sensors is captivating the attention of researchers to modern techniques,such as the internet of things(IoT)and mobile crowdsensing(MCS).The core concept behind MCS is to use the power of mobile sensors to accomplish a difficult task collaboratively,with each mobile user completing much simpler *** paper discusses the task assignment problem in mobile crowdsensing,which is dependent on sensing time and path planning with the constraints of participant travel distance budgets and sensing time *** goal is to minimize aggregate sensing time for mobile users,which reduces energy consumption to encourage more participants to engage in sensing activities and maximize total task *** paper introduces a two-phase task assignment framework called location time-based algorithm(LTBA).LTBA is a framework that enhances task assignment in MCS,whereas assigning tasks requires overlapping time intervals between tasks and mobile users’tasks and the location of tasks and mobile users’*** process of assigning the nearest task to the mobile user’s current path depends on the ant colony optimization algorithm(ACO)and Euclidean *** combines two algorithms:(1)greedy online allocation algorithm and(2)bio-inspired traveldistance-balance-based algorithm(B-DBA).The greedy algorithm was sensing time interval-based and worked on reducing the overall sensing time of the mobile user.B-DBA was location-based and worked on maximizing total task *** results demonstrate that the average task quality is 0.8158,0.7093,and 0.7733 for LTBA,B-DBA,and greedy,*** sensing time was reduced to 644,1782,and 685 time units for LTBA,B-DBA,and greedy,*** the algorithms improves task assignment in MCS for both total task quality and sensing *** results demonstrate that combining the two algorithms in LTBA is the best performance for total task quality and total sensing time,and the greed

关键词： Mobile crowdsensing online task assignment participatory sensing path planning sensing time intervals ant colony optimization

A Comparative Study on the Corrosion Performance of Ni_(47)Ti_(49)Co_4 and Ni_(51)Ti_(49) Shape Memory Alloys in Simulated Saliva Solution for Dental Applications

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Acta Metallurgica Sinica(English Letters) 2016年第11期29卷 1001-1010页

作者： rasha A.Ahmed Chemistry Department Faculty of Science Taif University Forensic Chemistry Laboratories Medico Legal DepartmentMinistry of Justice

In this study, the corrosion behavior of Ni47Ti49Co4 shape memory alloy（SMA） was investigated in simulated saliva solution with the binary alloy Ni（51）Ti49 as a reference. The surface morphology and the chemical composition of the oxide films were characterized by scanning electron microscopy and X-ray photoelectron spectroscopy before and after immersion in the test solutions, respectively. The results showed that the ternary alloy was less affected by the test solution,owning to the formation of passive layer composed mainly of the oxides of titanium and cobalt in several oxidation *** voltammetry, electrochemical impedance spectroscopy and potentiodynamic polarization measurements affirmed that the passive oxide film significantly improved the corrosion resistance of Ni47Ti49Co4 SMAs as demonstrated by the smaller corrosion current density, larger resistance and smaller capacitance. Consequently, alloying with cobalt, which has paramount importance in enhancing the passive layer, expands the use of Ni47Ti49Co4 SMAs in dental work as new nitinol alloys with high corrosion resistances.

关键词： Ni47Ti49Co4 Shape memory alloy (SMA) Corrosion Artificial saliva X-ray photoelectronspectroscopy (XPS)

Evaluation of GALAD Score in Diagnosis and Follow-up of Hepatocellular Carcinoma after Local Ablative Therapy

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Journal of Clinical and Translational Hepatology 2023年第2期11卷 334-340页

作者： rasha eletreby Marwa elsharkawy Alaa Awad Taha Mohamed Hassany Amr Abdelazeem Mohamed el-Kassas Ahmed Soliman Endemic Medicine Department Faculty of MedicineCairo UniversityCairoEgypt Clinical and Chemical Pathology Department Faculty of MedicineCairo UniversityCairoEgypt Hepatogastroenterology Department Theodore Bilharz Research InstituteGizaEgypt Hepatogastroenterology Department National Hepatology and Tropical Medicine Research InstituteCairoEgypt Endemic Medicine Department Faculty of MedicineHelwan UniversityCairoEgypt

Background and Aims:Strategies for detection of early hepatocellular carcinoma(HCC)are still *** GALAD score is a serum biomarker-based model designed to predict the probability of having *** aimed to assess the ability of GALAD score to diagnose early HCC and its validity to follow patients after local ablation ***:This multicenter prospective study included 108 patients in two groups,58 HCC patients(67 focal lesions)with local ablative therapy(study group),and a control group of 50 patients with liver *** GALAD scores of the study and control groups,and of the HCC patients before and after ablative therapy were ***:Most patients were men(74.1%in study group and 76%in controls)with hepatitis C virus infection(98.30%in the study group,and 94%in controls).GALAD scores were significantly higher in HCC patients than in those with benign cirrhosis(2.65 vs.−0.37,p=0.001).Ablative therapy was successful in 94.4%of focal lesionsell-ablated tumors(2.19 vs.0.98,p=0.001).The best cutoff values of GALAD score for diagnosis of early HCC,and for prediction of well ablation of HCC were 0.74 and≤3.31(areas under the curve of 0.92 and 0.75,sensitivities of 84.48%and 76.19%,specificities of 89.13%and 83.33%,positive predictive values of 90.74%and 94.1%,and negative predictive values of 82%and 35.7%respectively).Conclusion:The GALAD score was effective for the diagnosis of early HCC and for followup after ablative therapy.

关键词： GALAD score HCC Ablative therapy Liver cirrhosis Egypt

Squamous cell carcinoma metastatic to cervical lymph nodes from unknown primary origin:the impact of chemoradiotherapy

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Chinese Journal of Cancer 2012年第10期31卷 484-490页

作者： Hany eldeeb rasha Hamdy Hamed Oncology Center Northampton General HospitalNorthampton NN1 5BDUK Department of clinical Oncology and Nuclear Medicine Faculty of MedicineMansoura UniversityEgypt

The management of cervical lymph node metastases of squamous cell carcinoma from an unknown primary site is still a therapeutic *** report here our experience in treating these patients with chemoradiotherapy as a curative *** from 40 patients were *** total,20(50%) patients underwent excisional *** patients underwent radiotherapy,which was delivered to both sides of the neck and pharyngeal mucosa(extensive field),and concurrent chemotherapy consisting of weekly cisplatin at a dose of 40 mg/*** clinical stage of the cervical nodes at presentation was N1 in 25%,N2 in 60%,and N3 in 15%.Most patients(75%) developed at least grade 3 *** patients(20%) had grade 3 xerostomia and 18 patients(45%) required esophageal dilation for *** 5-year overall survival(OS) rate of all patients was 67.5%.The 5-year OS rates of patients with N1,N2,and N3 lesions were 100%,67%,and 41%,respectively(P = 0.046).The 5-year progression-free survival rate was 62.5%.In multivariate analysis,only N stage significantly affected OS(P = 0.022).Emergence of the occult primary was very limited(1 patient only).Our results suggest that extensive irradiation of both sides of the neck and pharyngeal mucosa with concurrent chemotherapy results in a lower emergence of primary *** the survival of patients with unknown primary is comparable to that of patients with known primary,an attempt at cure should always be made.

关键词：鳞状细胞癌淋巴结化疗放射治疗多变量分析生存率患者隐匿性

Comparative metabolomics of the different fractions of two saltwort(Salsola L.)species in relation to their anti-inflammatory activity

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Food Bioscience 2023年第1期51卷 937-949页

作者： Dina A.Selim Eman Shawky Doaa A.Ghareeb Shaymaa A.Abdulmalek rasha M.Abu el-Khair Department of Pharmacognosy Faculty of PharmacyAlexandria UniversityEgypt Bio-screening and Preclinical Trial Lab Biochemistry DepartmentFaculty of ScienceAlexandria UniversityAlexandriaEgypt Biochemistry Department Faculty of ScienceAlexandria UniversityAlexandriaEgypt Center of Excellence for Drug Preclinical Studies(CE-DPS) Pharmaceutical and Fermentation Industry Development CenterCity of Scientific Research&Technological Applications New Borg El ArabAlexandriaEgypt College of PharmacyArab Academy for ScienceTechnology and Maritime TransportAlexandriaEgypt

Many of the plants of genus Salsola are edible halophytes which are known for their use in treatment of inflammation as well as their nutritional *** study aims at comprehensive chemical profiling of two Salsola species that are widely distributed in arid areas;*** and ***,using UHPLC-QqQ-MS in an attempt to decipher the bioactive constituents of the aerial parts of the selected plants and their ex-vivo antiinflammatory activity.73 chromatographic peaks were annotated where phytosterols dominated the metabolites in *** while phenylalkylamines were the major constituents detected in ***-DA model coefficients plot indicated that tetradecanoic acid,beta sitosterol and pentacosane were positively correlated to discrimination of *** species while N-feruloyloctopamine,N-feruloyltyramine,and ferulic acid,were positively correlated to discrimination of *** ***,fractions of ***,reduced the 5 upregulation of TNF-αcaused by LPS to levels lower than those produced by piroxicam while the petroleum ether and n-butanol fraction of *** were more effective than piroxicam in reducing IL-6 gene *** coefficients plot depicted that methyl palmitate,aegicin,cleomiscoside,beta sitosterol and sitostanol possessed strong positive correlation to the down regulation of the pro-inflammatory marker TNF-α,IL-1βand IFN-γwhile only norepinephrine derivatives were the major metabolites that showed strong positive correlation to the inhibition of IL-6 pro-inflammatory *** results obtained may help to explain chemically,the potential anti-inflammatory effect of the various Salsola species fractions increasing the value of the Salsola species as a putative functional foods.

关键词： Salsola jordanicola Salsola imbricata Chemometrics Anti-inflammatory UPLC/MS/MS Metabolomics

electrochemical Detection of the Different Species of Levofloxacin Using PVC,Carbon Paste and Screen‑Printed electrodes:Effect of pH

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Journal of Analysis and Testing 2018年第2期2卷 175-183页

作者： Nour elDin T.Abdel Ghani Fatehy M.Abdel‑Haleem Sonia Mahmoud rasha M.el Nashar Chemistry Department Faculty of ScienceCairo UniversityGizaEgypt

The zwitterionic compound,levofloxacin,was determined for the first time at different pH values in pure samples,pharmaceutical preparations and spiked serum and urine *** types of potentiometric sensors including poly(vinyl chloride)membrane electrode,carbon paste electrode and screen printed electrode,containing the ion pair levofloxaciniumphosphomolybdate as the electroactaive species,were used for this *** effect of pH is the key factor in determining the ratio of the different species that can exist in the medium(zwitterionic,monocationic,dicationic,anionic and neutral),and so it is the controller of the electrochemical *** different sensors were fully characterized and optimized in terms of composition,pH effect,selectivity,response and *** different sensors showed reliable reversibility and could be utilized for the determination of the drug in real spiked physiological fluids with reliable recovery values.

关键词： Levofloxacin Zwitterionic Poly(vinyl-chloride)(PVC)membrane electrode Carbon paste electrode(CPE) Screen-printed electrode(SPE)