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Classical state feedback controller for nonlinear systems using mean value theorem： closed Ioop-FOC of PMSM motor application

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Frontiers in Energy 2015年第4期9卷 413-425页

作者： Abrar ALLAG abdelhamid BENAKCHA Meriem ALLAG Ismail ZEIN mohamed Yacine AYAD LGEB Laboratory Department of Electrical Engineering University of Biskra Biskra BP 145 Algeria R&D Industrial Hybrid Vehicle Applications Belfort 90010 France

The problem of state feedback controllers for a class of Takagi-Sugeno （T-S） Lipschitz nonlinear systems is investigated. A simple systematic and useful synthesis method is proposed based on the use of the differential mean value theorem （DMVT） and convex theory. The proposed design approach is based on the mean value theorem （MVT） to express the nonlinear error dynamics as a convex combination of known matrices with time varying coefficients as linear parameter varying （LPV） systems. Using the Lyapunov theory, stability conditions are obtained and expressed in terms of linear matrix inequalities （LMIs）. The controller gains are then obtained by solving linear matrix inequalities. The effectiveness of the proposed approach for closed loop-field oriented control （CL-FOC） of permanent magnet synchronous machine （PMSM） drives is demonstrated through an illustrative simulation for the proof of these approaches. Furthermore, an extension for controller design with parameter uncertainties and perturbation performance is discussed.

关键词： Takagi-Sugeno (T-S) fuzzy systems sectornonlinearity nonlinear controller linear matrix inequality(LMI) approach differential mean value theorem (DMVT),field oriented control (FOC) linear parameter varying(LPV)

Conjunctival flap advancement with or without scleral graft for hypotony maculopathy after trabeculectomy

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International Journal of Ophthalmology(English edition) 2020年第7期13卷 1079-1086页

作者： abdelhamid Shaker Elhofi mohamed Fahmy Doheim Amir AbouSamra Department of Ophthalmology Faculty of MedicineAlexandria UniversityAlexandria 21131Egypt Faculty of Medicine Alexandria UniversityAlexandria 21131Egypt

AIM: To investigate the outcomes of adaptive conjunctival flap advancement surgical techniques with or without scleral graft for patients undergoing revision surgery after ***: This retrospective study included 28 eyes of 28 subjects from December 2015 to April 2018. A group of 15 eyes underwent conjunctival advancement only while the other 13 eyes did conjunctival advancement with partial thickness scleral graft. In both study groups, we considered the intraocular pressure(IOP) as our primary outcome and visual acuity(VA) as our secondary outcome. Both were assessed pre-and post-operatively till the last followup possible point. Additionally, we classified the patients according to complete and qualified success ***: The mean age of the conjunctival advancement group was 36.87±19.25 y, while it was 44.08±18.04 in the other group. In both study groups, the mean IOP significantly increased after revision surgery at 1, 2, 3 mo and the last follow-up visit when compared to prior the surgery(P<0.001). Moreover, VA was significantly improved(P=0.03) in the final follow-up for both surgical techniques. When we compared the change from baseline in both groups, there was no significant difference between IOP improvement in 1 mo(P=0.263), while the difference was significant in 2 mo(P=0.03), 3 mo(P=0.02) and in the final follow-up visit postoperatively. However, this difference was not significant regarding VA(P=0.5).CONCLUSION: The both adaptive techniques of conjunctival advancement and conjunctival advancement with scleral graft are effective for treating patients with lateonset hypotony. Yet, more prospective studies are needed to assert upon these results.

关键词： trabeculectomy scleral melting revision surgery hypotony maculopathy

Noninvasive assessment of hepatic fibrosis in Egyptian patients with chronic hepatitis C virus infection

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World Journal of Gastroenterology 2012年第23期18卷 2988-2994页

作者： Shawky abdelhamid Fouad Serag Esmat Dalia Omran Laila Rashid mohamed H Kobaisi Department of Internal Medicine Faculty of Medicine Cairo University Cairo 11562 Egypt Department of Tropical Medicine Faculty of Medicine Cairo University Cairo 11562 Egypt Department of Biochemistry Faculty of Medicine Cairo University Cairo 11562 Egypt Department of Pathology National Institute of Nephrology Cairo 35789 Egypt

AIM: To evaluate the accuracy of specific biochemical markers for the assessment of hepatic fibrosis in patients with chronic hepatitis C virus (HCV) infection. METHODS: One hundred and fifty-four patients with chronic HCV infection were included in this study; 124 patients were non-cirrhotic, and 30 were cirrhotic. The following measurements were obtained in all patients: serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), albumin, total bilirubin, prothrombin time and concentration, complete blood count, hepatitis B surface antigen (HBsAg), HCVAb, HCV-RNA by quantitative polymerase chain reaction, abdominal ultrasound and ultrasonic-guided liver biopsy. The following ratios, scores and indices were calculated and compared with the results of the histopathological examination: AST/ALT ratio (AAR), age platelet index (API), AST to platelet ratio index (APRI), cirrhosis discriminating score (CDS), Pohl score, G teborg University Cirrhosis Index (GUCI). RESULTS: AAR, APRI, API and GUCI demonstrated good diagnostic accuracy of liver cirrhosis (80.5%, 79.2%, 76.6% and 80.5%, respectively); P values were: 0.05). In addition, we found significant correlations for the AAR, APRI, API, GUCI and Pohl score between the non-cirrhotic (F0, F1, F2, F3) and cirrhotic (F4) groups (P values: 0.05). CONCLUSION: The use of AAR, APRI, API, GUCI and Pohl score measurements may decrease the need

关键词： Age platelet index Aspartate aminotrans-ferase platelet ratio index Aspartate aminotransferase-to-alanine aminotransferase ratio Cirrhosis discrimi-nating score Fibrosis evaluation G^teborg UniversityCirrhosis Index Hepatitis C virus infection Liver fibro-sis Pohl score

A hydrochemical study of the Hammam Righa geothermal waters in north-central Algeria

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Acta Geochimica 2016年第3期35卷 271-287页

作者： mohamed Belhai Yasuhiro Fujimitsu Fatima Zohra Bouchareb-Haouchine abdelhamid Haouchine Jun Nishijima Department of Earth Resources Engineering GraduateSchool of EngineeringKyushu UniversityFukuoka 819-0395Japan Department of Earth Resources Engineering Faculty ofEngineeringKyushu UniversityFukuoka 819-0395Japan Laboratoire de Geo-Environnement FSTGAT/USTHB BP 32El-Alia16000 AlgiersAlgeria

This study focuses on the hydrochemical characteristics of 47 water samples collected from thermal and cold springs that emerge from the Hammam Righa geothermal field, located in north-central Algeria. The aquifer that feeds these springs is mainly situated in the deeply fractured Jurassic limestone and dolomite of the Zaccar Mount. Measured discharge temperatures of the cold waters range from 16.0 to 26.5 ℃ and the hot waters from 32.1 to 68.2 ℃. All waters exhibited a near-neutral pH of 6.0-7.6. The thermal waters had a high total dis- solved solids （TDS） content of up to 2527 mg/l, while the TDS for cold waters was 659.0-852.0 mg/l. Chemical analyses suggest that two main types of water exist： hot waters in the upflow area of the Ca-Na-SO4 type （Ham- mam Righa） and cold waters in the recharge zone of the Ca-Na-HCO3 type （Zaccar Mount）. Reservoir tempera- tures were estimated using silica geothermometers and fluid/mineral equilibria at 78, 92, and 95℃ for HR4, HR2, and HRI, respectively. Stable isotopic analyses of the δ18O and δD composition of the waters suggest that the thermal waters of Hammam Righa are of meteoric origin. We conclude that meteoric recharge infiltrates through the fractured dolomitic limestones of the Zaccar Mount and is conductively heated at a depth of 2.1-2.2 km. The hotwaters then interact at depth with Triassic evaporites located in the hydrothermal conduit （fault）, giving rise to the Ca-Na-SO4 water type. As they ascend to the surface, the thermal waters mix with shallower Mg-rich ground- water, resulting in waters that plot in the immature water field in the Na-K-Mg diagram. The mixing trend between cold groundwaters from the recharge zone area （Zaccar Mount） and hot waters in the upflow area （Hammam Righa） is apparent via a chloride-enthalpy diagram that shows a mixing ratio of 22.6 〈 R 〈 29.2 %. We summa- rize these results with a geothermal conceptual model of the Hammam Righa geothermal field.

关键词： Thermal waters North-central Algeria Geochemistry Geothermometry Geothermal conceptualmodel Cold groundwaters

Predictors of renal angioembolization outcome:A retrospective analysis with 148 patients at a tertiary urology institute

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Asian Journal of Urology 2022年第2期9卷 103-108页

作者： Hashim mohamed Farg mohamed mohamed Elawdy Karim Ali Soliman mohamed Ali Badawy Ali Elsorougy Abdalla abdelhamid Tarek Mohsen Tarek El-Diasty Department of Radiology Urology and Nephrology CentreMansoura UniversityMansouraEgypt Department of Urology Urology and Nephrology CentreMansoura UniversityMansouraEgypt

Objective:The aim of this study was to evaluate the predictor of unsuccessful outcome of renal angioembolization(RAE).Knowing those predictors may help in avoiding unnecessary RAE procedures and their associated side effects,while helping to prepare for an alternate procedure and improving patient's overall ***:A retrospective analysis between January 2006 and December 2018 was performed,and the indications for RAE were classified into post-traumatic,iatrogenic,renal tumors,and *** who underwent RAE prior to nephrectomy were *** tomography angiography was performed in patients with normal renal function and those who had no contrast allergy,otherwise magnetic resonance angiography was *** the purpose of statistical analysis,we stratified patients into two main categories based on the final outcome—successful or ***:Of 180 patients,32 with negative angiography were eliminated,leaving 148 patients;136(91%)had successful outcomes after one or more trials and 12 had unsuccessful *** mean age was 45±15 years,and 105(71%)were *** gender,side of the lesion,presence of hematuria,indication for RAE,nor the type of lesion affected the *** the other hand,renal anatomy with presence of accessory artery was the only predictor to failed RAE(p=0.001).Failed RAE trial was a predictor for nephrectomy as a secondary procedure(p=0.03).Conclusion:No pre-procedural predictors could anticipate the RAE outcome,and different indications can be scheduled to RAE,which is equally *** presence of accessory renal artery on diagnostic angiography is the only factor that may predict the failure of the procedure.

关键词： Angioembolization Renal angioembolization Embolization Renal trauma Outcome

Geochemical characterization of the salinity of irrigated soils in arid regions(Biskra, SE Algeria)

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Acta Geochimica 2021年第2期40卷 234-250页

作者： mohamed Amine Abdennour Abdelkader Douaoui Jesus Barrena Manuel Pulido abdelhamid Bradai Amel Bennacer Chiara Piccini Alberto Alfonso-Torreno Laboratory of Ecosystem Diversity and Agricultural Production System Dynamics in Arid Zones(DEDSPAZA) Mohamed Khider University07000 BiskraAlgeria Laboratory of Crop Production and Sustainable Valorization of Natural Resources Djilali Bounaama University44225 Khemis MilianaAlgeria GeoEnvironmental Research Group University of Extremadura10071 CaceresSpain Laboratory of Water and Environment Hassiba Ben Bouali University02180 ChiefAlgeria Laboratory of Valorization and Conservation of Biological Resources Faculty of SciencesMohamed Bougara University35000 BoumerdesAlgeria Research Centre for Agriculture and Environment Council for Agricultural Research and EconomicsVia della Navicella 2-400184 RomeItaly

The agriculture in Biskra,southeastern Algeria,is based on traditional practices and characterized by small irrigated *** the last decades,the increasing demand in water as well as the scarcity of rainfall has forced many farmers to use groundwater of low quality to maintain the profitability of their ***,this practice seems to be the main harmful factor for soil quality in the region since it is responsible for the salinization of the irrigated *** to assess the impact of this phenomenon,the soils of the irrigated perimeter of El Ghrous-a representative rural community located in the west of Biskra-have been analyzed.A set of 82 soil samples was collected from top and subsoil(0-15 and15-35 cm respectively),on which the following physicochemical analyzes were performed:Ca^(2+),Mg^(2+),K^(+),Na^(+),Cl^(-),SO_(4)^(2-),HCO_(3)^(-),NO_(3)^(-),pH,electrical conductivity(EC)and sodium adsorption ratio.A Principal Component Analysis was performed to individuate the geochemical processes that influenced significantly the evolution of soil salinity and its *** results showed a calcium sulfate(CaSO_(4))facies with a high risk of salinity and a low to medium risk of *** calcite residual alkalinity and generalized residual alkalinity decreased as the solutions became more *** of the samples were oversaturated in carbonate minerals(aragonite,calcite,and dolomite)and under saturated in evaporitic minerals(anhydrite,gypsum,and halite).Finally,two multiple linear regressions(using cations and anions as independent variables)have been proposed to quantify soil *** equations,with an accuracy of 85%,can represent a time and money-saving tool for managers and farmers to estimate the EC,in comparison to the traditional estimation methods.

关键词： Electrical conductivity Cations Anions Soil quality Saturation index PHREEQC

Renal arterial embolization:Indications,angiographic findings,and outcomes in a series of 170 patients

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Current Urology 2023年第3期17卷 213-218页

作者： Hashim mohamed Farg mohamed Elawdy Karim Ali Soliman mohamed Ali Badawy Ali Elsorougy Tarek Mohsen Tarek El-Diasty Abdalla abdelhamid Urology Department Urology and Nephrology CenterMansoura UniversityMansoura35516Egypt

Background:The lack of overall experience and reporting on angiographic findings in previously published studies of renal arterial embolization(RAE)compelled us to report our overall experience on a series of *** and methods:A retrospective study was performed analyzing data of patients enrolled for RAE between 2010 and ***,physical examination,and laboratory data were reviewed for all *** ultrasound was the initial imaging study,and all patients underwent subsequent computed tomography or magnetic resonance *** outcome of RAE was determined based on radiographic and clinical ***:Data from 202 patients were analyzed,with a mean age of 45±15 years,and 71.3%of patients were *** injury was the most common indication for RAE(54%),followed by renal tumors,trauma,and spontaneous,in 27.7%,10.4%,and 8.4%of patients,*** angiography revealing pseudoaneurysm alone or with other pathology in the lower pole of the kidney was the most common finding(40.6%),whereas no lesions were identified on angiography in 32 patients(15.8%),after which RAE was subsequently *** arterial embolization was successful in 158 of 170 patients(92.9%)after 1 or more trials(maximum of 4).Microcoil alone or with other embolic materials was the most commonly used material for embolization(85%).Conclusions:latrogenic injury was the most common indication for *** alone or with other lesions was the most common lesion on renal angiography;however,angiography showed a negative result in 16%of patients,even those with *** lesions are present on angiography,the overall success of repeated trials of RAE reached 92.9%.

关键词： Angiographic findings Embolization Renal angioembolization Renal arterial embolization

Transfer Learning for Chest X-rays Diagnosis Using Dipper Throated Algorithm

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Computers, Materials & Continua 2022年第11期73卷 2371-2387页

作者： Hussah Nasser AlEisa El-Sayed M.El-kenawy Amel Ali Alhussan mohamed Saber Abdelaziz A.abdelhamid Doaa Sami Khafaga Department of Computer Sciences College of Computer and Information SciencesPrincess Nourah Bint Abdulrahman UniversityRiyadh11671Saudi Arabia Department of Communications and Electronics Delta Higher Institute of Engineering and TechnologyMansoura35111Egypt Faculty of Artificial Intelligence Delta University for Science and TechnologyMansoura35712Egypt Electronics and Communications Engineering Department Faculty of EngineeringDelta University for Science and TechnologyMansoura35712Egypt Department of Computer Science Faculty of Computer and Information SciencesAin Shams UniversityCairo11566Egypt Department of Computer Science College of Computing and Information TechnologyShaqra University11961Saudi Arabia

Most children and elderly people worldwide die from pneumonia,which is a contagious illness that causes lung *** diagnosing pneumonia from chest X-ray images,many deep learning models have been put *** goal of this research is to develop an effective and strong approach for detecting and categorizing pneumonia *** varying the deep learning approach,three pre-trained models,GoogLeNet,ResNet18,and DenseNet121,are employed in this research to extract the main features of pneumonia and normal *** addition,the binary dipper throated optimization(DTO)algorithm is utilized to select the most significant features,which are then fed to the K-nearest neighbor(KNN)classifier for getting the final classification *** guarantee the best performance of KNN,its main parameter(K)is optimized using the continuous DTO *** test the proposed approach,six evaluation metrics were employed namely,positive and negative predictive values,accuracy,specificity,sensitivity,and ***,the proposed approach is compared with other traditional approaches,and the findings confirmed the superiority of the proposed approach in terms of all the evaluation *** minimum accuracy achieved by the proposed approach is(98.5%),and the maximum accuracy is(99.8%)when different test cases are included in the evaluation experiments.

关键词： Metaheuristic pneumonia dipper throated optimization KNN

The Upper Jurassic sediments,Marib-Shabwa Basin,Yemen:Lithofacies aspects and sequence stratigraphic analysis

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Energy Geoscience 2024年第1期5卷 342-357页

作者： Mohammed Albaroot mohamed M.Elhossainy Nabil M.Al-Areeq Emad A.Abdullah abdelhamid M.Salman Department of Applied Geology Faculty of Science and EducationUniversity of Saba RegionMaribYemen Department of Geology Faculty of ScienceKafrelsheikh UniversityKafrelsheikh33516Egypt Department of Geology and Environment Faculty of Applied SciencesThamar UniversityYemen Department of Mineral Developing and Oil&Gas Engineering Academy of EngineeringPeoples’Friendship University of Russia(RUDN University)Moscow117198Russia Department of Geology Faculty of ScienceAssiut UniversityAssiut71516Egypt

The present study is devoted to understanding the evolution of the Upper Jurassic Sab'atayn Formation in the Marib-Shabwa Basin,Yemen,through a sequence stratigraphic analysis based on integrating datasets of sedimentology,seismic sections,and well *** Sab'atayn Formation(Tithonian age)is represented by a series of clastic and evaporites that were deposited under fluvio-deltaic to prodeltaic *** is divided into four members including Yah(at the base),upwards to Seen,Alif,and Safir at the *** third-order depositional sequences were determined for the Tithonian succession which were separated by three sequence *** sequences were classified into their systems tracts signifying several sedimentation patterns of progradational,aggradational,and retrogradational parasequence *** first depositional sequence corresponds to the early-middle Tithonian Yah and Seen units that can be classified into lowstand,transgressive,and highstand systems *** second sequence comprises the late Tithonian Alif unit that can be subdivided into transgressive and highstand systems *** sandy deposits of the Alif Member(highstand deposits)represent the most productive hydrocarbon reservoir in the *** Upper Jurassic sediments in the study area were resulted from a combination of eustatic and tectonic effects.

关键词： Sequence stratigraphy Sandstone reservoir Well logs Upper Jurassic Marib-Shabwa Basin Yemen