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

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

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A Class of Pseudo-Real Riemann Surfaces with Diagonal Automorphism Group

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Algebra Colloquium 2020年第2期27卷 247-262页

作者： eslam Badr Department of mathematics Facility of Science Cairo UniversityGiza 12613Egypt

A Riemann surface S having field of moduli m,but not a field of definition,is called *** means that S has anticonformal automorphisms,but none of them is an involution.A Riemann surface is said to be plane if it can be described by a smooth plane model of some degree d≥4 in P^2/*** characterize pseudo-real-plane Riemann surfaces»S,whose conformal automorphism group Aut+(S)is PGL3(C)-conjugate to a finite non-trivial group that leaves invariant infinitely many points of P^2/*** particular,we show that such pseudo-real-plane Riemann surfaces exist only if Aut+(S)is cyclic of even order n dividing the degree *** families of pseudo-reai-plane Riemann surfaces are given for any degree d=2pm with m>1 odd,p prime and n=d/p.

关键词： pseudo-real Riemann surface field of moduli field of definition plane curve automorphism group

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Comparison of fixed area and distance sampling methods in open forests:case study of Zagros Forest,Iran

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Journal of Forestry Research 2016年第5期27卷 1121-1126页

作者： mehrdad mirzaei Amir eslam Bonyad University of Guilan

The main aim of this study was to evaluate methods for fixed area and distance sampling in the Zagros open forest area in western Iran. Basic forest management and planning required appropriate quantitative and qualitative information. Two sampling methods were compared on the basis of the actual means of characteristics derived from the 100 % survey. In total, 37 sampling plots were systematically installed with a grid of 100 m × 100 m in the study area. Density, crown canopy, and basal area of the stands were measured. The 100 % survey showed that tree density above 12.5 cm diameter at breast height was 68.04 stem ha-1, basal area was 15.16 m2 ha-1 and crown canopy percentage was 35.71% ha-1. The values for the traits determined by the two sampling methods differed significantly （P = 0.05）. When the time required for the methods was compared, transect sampling required less than systematic-random sampling. Therefore, the transect sampling method was the more economical method for the Zagros open forests. The transect sampling method was statistically defensible and practical for quantitating characteristics of the Zagros open forests.

关键词： Ilam - Systematic random sampling Transect sampling Zagros Forest

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A Transfer Learning Approach Based on Ultrasound Images for Liver Cancer Detection

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Computers, materials & Continua 2023年第6期75卷 5105-5121页

作者： murtada K.Elbashir Alshimaa mahmoud Ayman mohamed mostafa eslam Hamouda meshrif Alruily Sadeem m.Alotaibi Hosameldeen Shabana mohamed Ezz College of Computer and Information Sciences Jouf UniversitySakaka72314Saudi Arabia Department of Information Systems MCI AcademyCairoEgypt College of medicine Shaqra UniversityShaqraKSA Faculty of medicine Al Azhar UniversityCairoEgypt

The convolutional neural network(CNN)is one of the main algorithms that is applied to deep transfer learning for classifying two essential types of liver lesions;Hemangioma and hepatocellular carcinoma(HCC).Ultrasound images,which are commonly available and have low cost and low risk compared to computerized tomography(CT)scan images,will be used as input for the model.A total of 350 ultrasound images belonging to 59 patients are *** number of images with HCC is 202 and 148,*** images were collected from ultrasound ***(28 Hemangiomas patients and 11 HCC patients),the department of radiology,the University of Washington(7 HCC patients),the Atlas of ultrasound Germany(3 HCC patients),and Radiopedia and others(10 HCC patients).The ultrasound images are divided into 225,52,and 73 for training,validation,and testing.A data augmentation technique is used to enhance the validation *** proposed an approach based on ensembles of the best-selected deep transfer models from the on-the-shelf models:VGG16,VGG19,DenseNet,Inception,InceptionResNet,ResNet,and *** tuning both the feature extraction and the classification layers,the best models are *** accuracy is used for model tuning and *** accuracy,sensitivity,specificity and AUROC are used to evaluate the *** experiments are concluded in five *** first stage aims to evaluate the base model performance by training the on-the-shelf *** best accu-racy obtained in the first stage is 83.5%.In the second stage,we augmented the data and retrained the on-the-shelf models with the augmented *** best accuracy we obtained in the second stage was 86.3%.In the third stage,we tuned the feature extraction layers of the on-the-shelf *** best accuracy obtained in the third stage is 89%.In the fourth stage,we fine-tuned the classification layer and obtained an accuracy of 93%as the best *** the fifth stage,we applied the en

关键词： Transfer learning liver lesions ultrasound images and convolutional neural network

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Effect of Succinonitrile on Electrical, Structural and Thermal Properties of PVA-Based Polymer Electrolyte for magnesium Battery

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Journal of Energy and Power Engineering 2014年第6期8卷 1159-1165页

作者： Belal m. Abdel-Samiea Rania Gamal eslam m. Sheha Physics Department Faculty of Science Benha University Benha 13518 Egypt

This paper report the synthesis and properties of a series of composite polymer electrolytes formed by dispersion of a non-ionic organic plastic material SN （succinonitrile） into poly（vinyl alcohol） complexed with magnesium acid salt. SEm （scanning electron microscope） images of different SN concentrations of films revealed that large open pore structure were also frequently present, when SN content increase up to 7.5 wt%. The addition of SN greatly enhances ionic conductivities of the electrolytes which is due to the high polarity and diffusivity of SN. The mg2~ （magnesium ion） ion conduction is confirmed from impedance spectroscopy and transport number measurements. The highest conducting sample in the plasticized system was used to fabricate mg （magnesium） battery with configuration mg/SPE/TiO2. The discharge capacity of the fabricated battery was 17.5 mAh/gm.

关键词： Polymer electrolyte succinonitrile.

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Evaluation of the chemical constituents,antioxidant and enzyme inhibitory activities of six Yemeni green coffee beans varieties

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Food Bioscience 2022年第2期46卷 1006-1013页

作者： Ammar mohammed Ahmed Ali Sakina Yagi Ahmed A.Qahtan Abdurrahman A.Alatar Simone Angeloni Filippo maggi Giovanni Caprioli eslam m.Abdel-Salam Kouadio Ibrahime Sinan Gokhan Zengin Department of Biology Faculty of EducationHajji UniversityHajjahYemen Botany Department Faculty of ScienceUniversity of KhartoumSudan Department of Botany&microbiology College of ScienceKing Saud UniversityP.O.Box 2455Riyadh11451Saudi Arabia Chemistry Interdisciplinary Project(ChIP) School of PharmacyUniversity of CamerinoVia Madonna delle Carceri 9/BI62032CamerinoMCItaly Physiology and Biochemistry Laboratory Department of BiologyScience FacultySelcuk UniversityCampus42103KonyaTurkey

Coffee arabica *** an economical crop cultivated in many countries including *** present study evaluated the phytochemical contents of the methanolic extracts,prepared by maceration,of six Yemeni green coffee beans varieties namely Esmaeli,Hamadi,Harazi,mattari,Odaini and ***(phosphomolybdenum,antiradical,reducing power and ferrous chelating),and enzyme inhibition activity of the extracts against acetylcholinesterase butyrylcholinesterase,tyrosinase,α-glucosidase,andα-amylase were also *** of total phenols revealed that all green beans varieties were richer in their total polyphenolic(63.77-110.98 mg gallic acid equivalent per g of extract)content than their flavonoids one(2.86-5.57 mg rutin equivalent per g of extract).HPLC-mS/mS analysis of 30 selected bioactive compounds showed that all varieties had the same types of phytoconstituents with differences in their relative ***(1613.89-2466.38μg/g)followed by 5-caffeoylquinic acid(1017.63-1313.39μg/g)were the dominant compounds in all varieties with caffeine more abundant in Esmaeli variety while 5-caffeoylquinic acid in Odaini *** varieties displayed a pronounced antioxidant property in all the in vitro assays with Odaini variety significantly(pmg Trolox equivalent(TE)/g),metal chelating(19.73 mg Disodium edetate equivalents/g),Cu^(2+)(441.11 mg TE/g)and Fe3+(221.04 mg TE/g)reducing ***,the majority of green coffee beans varieties showed comparable enzyme inhibition property with highest activity recorded against tyrosinase(39.35-46.96 mg kojic acid equivalents/g)and acetylcholinesterase(1.80-2.17 mg galanthamine equivalents/g)*** conclusion,all Yemeni green coffee beans varieties have proven to be rich source of biochemicals with beneficial impact on human health and could be of significant applications in food,pharmaceutical and cosmetics industry.

关键词： Yemeni coffee Phytoconstituents Green coffee HPLC-mS/mS Antioxidants Enzyme inhibitory properties

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Crop Discrimination Using Field Hyper Spectral Remotely Sensed Data

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Advances in Remote Sensing 2013年第2期2卷 63-70页

作者： Sayed m. Arafat mohamed A. Aboelghar eslam F. Ahmed Agriculture Applications Department National Authority for Remote Sensing and Space Sciences (NARSS)Cairo Egypt

Crop discrimination through satellite imagery is still problematic. Accuracy of crop classification for high spatial resolution satellite imagery in the intensively cultivated lands of the Egyptian Nile delta is still low. Therefore, the main objective of this research is to determine the optimal hyperspectral wavebands in the spectral range of (400 - 2500 nm) to discriminate between two winter crops (Wheat and Clover) and two summer crops (maize and Rice). This is considered as a first step to improve crop classification through satellite imagery in the intensively cultivated areas in Egypt. Hyperspectral ground measurements of ASD field Spec3 spectroradiometer was used to monitor the spectral reflectance profile during the period of the maximum growth stage of the four crops. 1-nm-wide was aggregated to 10-nm-wide bandwidths. After accounting for atmospheric windows and/or areas of significant noise, a total of 2150 narrow bands in 400 - 2500 nm were used in the analysis. Spectral reflectance was divided into six spectral zones: blue, green, red, near-infrared, shortwave infrared-I and shortwave infrared-II. One Way ANOVA and Tukey’s HSD post hoc analysis was performed to choose the optimal spectral zone that could be used to differentiate the different crops. Then, linear regression discrimination (LDA) was used to identify the specific optimal wavebands in the spectral zones in which each crop could be spectrally identified. The results of Tukey’s HSD showed that blue, NIR, SWIR-1 and SWIR-2 spectral zones are more sufficient in the discrimination between wheat and clover than green and red spectral zones. At the same time, all spectral zones were quite sufficient to discriminate between rice and maize. The results of (LDA) showed that the wavelength zone (727:1299 nm) was the optimal to identify clover crop while three zones (350:712, 1451:1562, 1951:2349 nm) could be used to identify wheat crop. The spectral zone (730:1299 nm) was the optimal to identify maize

关键词： Hyper Spectral Data Crop Discrimination

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Ovarian thecal metaplasia of the adrenal gland in association with Beckwith-Wiedemann syndrome

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World Journal of Radiology 2014年第12期6卷 919-923页

作者： eslam Y Wassal mouhammed Amir Habra Rafael Vicens Priya Rao Khaled m Elsayes Department of Diagnostic Radiology University of Texas MD Anderson Cancer Center Department of Endocrine Neoplasia and Hormonal Disorders University of Texas MD Anderson Cancer Center Department of Pathology University of Texas MD Anderson Cancer Center

Beckwith-Wiedemann syndrome(BWS) is an overgrowth syndrome associated with increased risk to develop malignancies including adrenocortical carcinoma. Ovarian thecal metaplasia of the adrenal gland is a rare tumorlike mesenchymal lesion in BWS patients that lacks detailed radiological description. We report a 17-yearold female patient with BWS, associated with bilateral Wilms tumor, hepatic hemangiomatosis, pancreatic neuroendocrine tumor, and a phyllodes tumor of the right breast. Surveillance abdominal ultrasound identified a right adrenal mass that was further characterized by computed tomography and magnetic resonance imaging. Radiologically, this mass displayed features that overlap with adrenocortical carcinoma and pheochromocytoma but after pathological examination this proved to be an ovarian thecal metaplasia of the adrenal gland. Adrenal masses in BWS should raise the suspicion for adrenocortical carcinoma though other adrenal tumors including ovarian thecal metaplasia can be seen in these patients.

关键词： Ovarian thecal metaplasia Adrenal gland Wilms tumor Beckwith-Wiedemann syndrome Computed tomography magnetic resonance imaging Adrenocortical carcinoma

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Sonographic gallbladder wall thickness measurement and the prediction of esophageal varices among cirrhotics

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World Journal of Hepatology 2023年第2期15卷 216-224页

作者： mohamed H Emara mariam Zaghloul Ibrahim F Amer Aya m mahros mohammed Hussien Ahmed mahmoud A Elkerdawy eslam Elshenawy Abdelrahman m Ahmed Rasheda Tarik I Zaher mona Talaat Haseeb Emad Hassan Emara Hassan Elbatae Department of Hepatology Gastroenterology and Infectious DiseasesKafrelsheikh UniversityKafr-Elshikh 33516Egypt Department of Internal medicine Gastroenterology UnitSecurity Forces HospitalRiyadh 11481Saudi Arabia Tropical medicine Zagazig UniversityZagazig 44519Egypt Department of Diagnostic and Interventional Radiology Kafrelsheikh UniversityKafr-Elshikh 33516Egypt

Acute variceal bleeding in patients with liver cirrhosis and portal hypertension(PHT) is the most serious emergency complication among those patients and could have catastrophic outcomes if not timely managed. Early screening by esophago-gastro-duodenoscopy(EGD) for the presence of esophageal varices(EVs) is currently recommended by the practice guidelines for all cirrhotic patients. meanwhile, EGD is not readily accepted or preferred by many patients. The literature is rich in studies to investigate and validate non-invasive markers of EVs prediction aiming at reducing the unneeded endoscopic procedures. Gallbladder(GB) wall thickness(GBWT) measurement has been found promising in many published research articles. We aim to highlight the validity of sonographic GBWT measurement in the prediction of EVs based on the available evidence. We searched databases including Cochrane library, Pub med, Web of Science and many others for relevant articles. GBWT is associated with the presence of EVs in cirrhotic patients with PHT of different etiologies. The cut-off of GBWT that can predict the presence of EVs varied in the literature and ranges from 3.1 mm to 4.35 mm with variable sensitivities of 46%-90.9% and lower cutoffs in viral cirrhosis compared to non-viral, however GBWT > 4 mm in many studies is associated with acceptable sensitivity up to 90%. Furthermore, a relation was also noticed with the degree of varices and portal hypertensive *** cirrhotics, GBWT > 3.5 mm predicts the presence of advanced(grade Ⅲ-Ⅳ) EVs with a sensitivity of 45%, the sensitivity increased to 92% when a cut-off ≥ 3.95 mm was used in another cohort. Analysis of these results should carefully be revised in the context of ascites, hypoalbuminemia and other intrinsic GB diseases among cirrhotic patients. The sensitivity for prediction of EVs improved upon combining GBWT measurement with other non-invasive predictors, e.g., platelets/GBWT.

关键词： Sonographic Gallbladder wall thickness Prediction Esophageal varices Portal hypertension Esophago-gastro-duodenoscopy

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Interaction of IFNL3 with insulin resistance,steatosis and lipid metabolism in chronic hepatitis C virus infection

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World Journal of Gastroenterology 2013年第41期19卷 7055-7061页

作者： mohammed eslam David R Booth Jacob George Golo Ahlenstiel Storr Liver Unit Westmead Millennium Institute and Westmead HospitalUniversity of SydneySydneyNSW 2145Australia Institute for Immunology and Allergy Research Westmead Millennium InstituteUniversity of SydneySydneyNSW 2145Australia

metabolic changes are inextricably linked to chronic hepatitis C(CHC).Recently polymorphisms in the IFNL3(IL28B)region have been shown to be strongly associated with spontaneous and treatment induced recovery from hepatitis C virus(HCV)***,circumstantial evidence suggests a link between IFNL3single nucleotide polymorphisms and lipid metabolism,steatosis and insulin resistance in *** emerging picture suggests that the responder genotypes of IFNL3polymorphisms are associated with a higher serum lipid profile,and less frequent steatosis and insulin *** review analyzes the current data regarding this interaction and its meaning for HCV pathogenesis and disease progression.

关键词： IFNL3 Chronic hepatitis C Insulin resistance Lipids

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