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Towards a standardisation for digital inputs and outputs of protection functions in IEC 60255 series

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Protection and Control of Modern Power Systems 2022年第1期7卷 382-392页

作者： Volker Leitloff Hao Chen Dehui Chen Andrea Bonetti Lei Xu ahmed mohamed Carl Byman French Transmission Network Operator Rte ParisFrance State Grid Jiangsu Electric Power Co. Ltd.NanjingChina State Grid Electric Power Institute NanjingChina Royal Institute of Technology StockholmSweden NR Elec-tric Co. Ltd.NanjingChina Scottish and Southern Energy Network(SSEN) GlasgowUK Hitachi Energy VästeråsSweden.

Fully digitalized substations using IEC 61850 process bus are being introduced all over the *** utilities have featured pilot projects,demonstrators or even industrial scale deployment of these Fully Digital Protection,Auto-mation and Control Systems(FD-PACS).Product standards such as profiles for Instrument Transformers have been developed and published(IEC 61869-6 and IEC 61869-9 by TC 38-Instrument Transformers).This raises the question about the standards for digitally interfaced protection *** 2016,IEC TC 95(Measuring relays and protection equipment)charged a working group to investigate this subject and to elaborate recommendations concerning requirements and testing of protection IED with digital inputs and outputs for protection standards(IEC 60255-1xx series).For protection functions,publisher/subscriber based data streams are supposed to comply with IEC 61850 and IEC 61869 *** holds in particular for Sampled Values(SV)representing energising inputs of the protection function,and is also applicable to Generic Object Oriented Substation Event(GOOSE)which can be used for input or output of protection *** attributes of published data depend on the operational and connection status of the function and the hosting *** addition,protection functions have to take into account the information regarding the time synchronisation of the received SV and other *** paper gives an overview of these features and the proposed way to take them into account in the IEC 60255 standard *** describes the progress of WG 2 and relates it to existing standardization documents.

关键词： Process bus Protection function Digital interface SAMU LPIT Standards IEC 61850

A Hybrid Deep Learning Approach to Classify the Plant Leaf Species

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Computers, Materials & Continua 2023年第9期76卷 3897-3920页

作者： Javed Rashid Imran Khan Irshad ahmed Abbasi Muhammad Rizwan Saeed Mubbashar Saddique mohamed Abbas Department of CS&SE Islamic International UniversityIslamabad44000Pakistan Department of IT Services University of OkaraOkara56310Pakistan Faculty of Science and Arts Belqarn University of BishaSabtul Alaya61985Saudi Arabia Department of CS University of OkaraOkara56310Pakistan Department of Computer Science&Engineering University of Engineering&Technology LahoreNarowalCampusNarowal51601Pakistan Electrical Engineering Department College of EngineeringKing Khalid UniversityAbha61421Saudi Arabia Research Center for Advanced Materials Sciences(RCAMS) King Khalid UniversityAbhaSaudi Arabia

Many plant species have a startling degree of morphological similarity,making it difficult to split and categorize them *** plant species can be challenging to classify and segment using deep *** using deep learning architectures has helped improve classification accuracy,the resulting models often need to be more flexible and require a large dataset to *** the sake of taxonomy,this research proposes a hybrid method for categorizing guava,potato,and java *** new approaches are used to formthe hybridmodel suggested *** guava,potato,and java plum plant species have been successfully segmented using the first model built on the MobileNetV2-UNET *** a second model,we use a Plant Species Detection Stacking Ensemble Deep Learning Model(PSD-SE-DLM)to identify potatoes,java plums,and *** proposed models were trained using data collected in Punjab,Pakistan,consisting of images of healthy and sick leaves from guava,java plum,and *** datasets are known as PLSD and *** levels of 99.84%and 96.38%were achieved for the suggested PSD-SE-DLM and MobileNetV2-UNET models,respectively.

关键词： Plant leaf species stacking ensemble model guava potato java plum MobileNetV2-UNET hybrid deep learning segmentation

Low-voltage ride-through capability improvement of Type-3 wind turbine through active disturbance rejection feedback control-based dynamic voltage restorer

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Clean Energy 2023年第5期7卷 1091-1109页

作者： El Mahfoud Boulaoutaq Asma Aziz Abdelmounime El Magri ahmed Abbou mohamed Ajaamoum Azeddine Rachdy Ibn Zohr University Higher School of Technology Agadir School of Engineering Edith Cowan UniversityJoondalupWAaustralia Hassan II University of Casablanca National School of Technical Education Mohammed V University of Rabat Mohammadia School of Engineering

Disconnections due to voltage drops in the grid cannot be permitted if wind turbines(WTs)contribute significantly to electricity pro-duction,as this increases the risk of production loss and destabilizes the *** mitigate the negative effects of these occurrences,WTs must be able to ride through the low-voltage conditions and inject reactive current to provide dynamic voltage *** paper investigates the low-voltage ride-through(LVRT)capability enhancement of a Type-3 WT utilizing a dynamic voltage restorer(DVR).During the grid voltage drop,the DVR quickly injects a compensating voltage to keep the stator voltage *** paper proposes an active disturbance rejection control(ADRC)scheme to control the rotor-side,grid-side and DVR-side converters in a wind–DVR integrated *** performance of the Type-3 WT with DVR topology is evaluated under various test conditions using MATLAB®/Simulink®.These simulation results are also compared with the experimental results for the LVRT capability performed on a WT emulator equipped with a crowbar and direct current(DC)*** simulation results demonstrate a favourable transient and steady-state response of the Type-3 wind turbine quantities defined by the LVRT codes,as well as improved reactive power support under balanced fault *** the most severe voltage drop of 95%,the stator currents,rotor currents and DC bus voltage are 1.25 pu,1.40 pu and 1.09 UDC,respectively,conforming to the values of the LVRT *** controlled by the ADRC technique significantly increases the LVRT capabilities of a Type-3 doubly-fed induction generator-based WT under symmetrical voltage dip *** setting up ADRC controllers might be challenging,the proposed method has been shown to be extremely effective in reducing all kinds of internal and external disturbances.

关键词： active disturbance rejection controller(ADRC) dynamic voltage restorer(DVR) low-voltage ride-through(LVRT) Type-3 wind turbines(WTs) doubly-fed induction generator(DFIG)

A comprehensive review on residual stresses in turning

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Advances in Manufacturing 2022年第2期10卷 287-312页

作者： Ammar H.Elsheikh S.Shanmugan T.Muthuramalingam Amrit Kumar Thakur F.A.Essa ahmed mohamed Mahmoud Ibrahim ahmed O.Mosleh Department of Production Engineering and Mechanical Design Facultyof EngineeringTanta UniversityTanta 31527Egypt Research Centre for Solar Energy Department of PhysicsKoneru Lakshmaiah Education FoundationVaddeswaramAndhra Pradesh 522502India Department of Mechatronics Engineering SRM Institute of Science and TechnologyChennai 603203India Department of Mechanical Engineering KPR Institute Engineering and TechnologyCoimbatoreTamilnaduIndia Department of Mechanical Engineering Faculty of EngineeringKafrelsheikh UniversityKafrelsheikh 33516Egypt Production Engineering and Mechanical Design Department Faculty of EngineeringMinia UniversityMinya 61519Egypt Shoubra Faculty of Engineering Benha UniversityBenhaEgypt

Residual stresses induced during turning processes can affect thequality and performance of machined products,depending on its direction and *** stresses can be highly detrimental as they can lead to creeping,fatigue,and stress corrosion *** final state of residual stresses in a workpiece depends on its material as well as the cutting-tool configuration such as tool geometry/coating,cooling and wear conditions,and process parameters including the cutting speed,depth-ofcut and ***,there have been disagreements in some literatures regarding influences of the abovementioned factors on residual stresses due to different cutting conditions,tool parameters and workpiece materials used in the specific *** review paper categorizes different methods in experimental,numerical and analytical approaches employed for determining induced residual stresses and their relationships with cutting conditions in a turning *** is presented for the effects of different cutting conditions and parameters on the final residual stresses state.

关键词： Residual stresses Machining Turning:Process parameters

Mud Wasps and Its Role in the Destruction of Ancient Buildings in Application to the Temple of Isis in the Temple of Dandara, Qena, Egypt and Methods of Prevention

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Journal of Building Construction and Planning Research 2022年第1期10卷 37-53页

作者： Elashmawy ahmed Abd-Elkareem Hany ahmed fouad Conservation Department Faculty of Archaeology South Valley University Qena Egypt Plant Protection Department Faculty of Agriculture Sohage University Shage Egypt

Mud wasps are one of the most important problems that many archaeological sites suffer from in Egypt, especially in southern Egypt. Wasp’s growth increases, especially on the surface of stones or on mud-brick buildings, which represents a major challenge to these archaeological sites. It works to hide the stone surfaces and archaeological inscriptions found on them in addition to that it works to damage the stone surfaces themselves through the nests that they build on these surfaces. It works on weakening the structure of sandstone and the study that included a study on mud wasps and Analysis of nests and studied through the use of various devices and methods, the damage and its nature have also been studied as a result of the presence of wasp nests and the reasons for their existence. Various treatment methods and the best appropriate methods for treating sandstone and stopping wasp activity have also been studied.

关键词： Mud Wasps Sandstone Temple of Isis Destruction Treatment

Prediction of fold-of-increase in productivity index post limited entry fracturing using artificial neural network

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Petroleum Research 2022年第2期7卷 236-245页

作者： Shady Galal Ramah mohamed Abdalla Othman ahmed Z.Nouh Tarek El-Kwidy Faculty of Petroleum Engineering Suez UniversityEgypt Qarun Petroleum Company Egypt Egyptian Petroleum Research Institute Egypt American University in Cairo Egypt

Unified Fracture Design(UFD)bridges the gap between practices and theory in the hydraulic fracturing *** represents a technique to design hydraulic fracturing treatment with a particular amount of *** design could provide the maximum fold-of-increase(FOI)in productivity-index(PI)after hydraulic fracturing *** UFD optimization tool is very effective,but it has assumptions like any other *** assumption of UFD optimization technique;is a single-layer *** assumption does not align with the limited entry fracturing design *** limited entry fracturing,the frictional pressure is employed to offset the stress differences between multi-layers reservoirs to attain fluid injection through these layers,intended to deliver an optimal fracture conductivity in all *** drawback of this assumption is the underestimation of the actual value of FOI in *** paper aims to recast the original unified fracture design approach to extend the optimal UFD to a multilayer reservoir to predict the FOI in PI after limited entry fracturing *** recasting tool for this problem to find the optimum solution is Artificial Neural Networks(ANN).The architected ANN model is based on actual historical data of limited entry fracturing treatments.A statistical comparison between the proposed ANN model and classical UFD technique demonstrates that ANN model solution has a more reliable estimation of FOI in PI with the actual historical data.

关键词： Unified fracture design Hydraulic fracturing Limited-entry Fold of increase Artificial neural networks

Evaluation of children and adults with post-COVID-19 persistent smell,taste and trigeminal chemosensory disorders:A hospital based study

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World Journal of Clinical Pediatrics 2023年第3期12卷 133-150页

作者： Sherifa ahmed Hamed Eman Bahaa Kamal-Eldeen mohamed Azzam Abdel-Razek ahmed Department of Neurology and Psychiatry Assiut UniversityFaculty of MedicineAssiut 71516Egypt Department of Pediatrics Assiut UniversityFaculty of MedicineAssiut 71516Egypt Department of ENT Assiut UniversityFaculty of MedicineAssiut 71516Egypt

BACKGROUND Smell disorders are the most frequent persistent coronavirus disease 2019(COVID-19)*** To describe the patterns and characteristics of persistent smell and taste disorders in Egyptian *** Assessment was done to 185 patients(adults=150,age:31.41±8.63 years;children=35;age:15.66±1.63 years).Otolaryngology and neuropsychiatric evaluations were *** included:A clinical questionnaire(for smell and taste);sniffin'odor,taste and flavor identification tests and the Questionnaire of Olfactory Disorders-Negative Statements(sQOD-NS).RESULTS Duration of disorders was 11.53±3.97 ms(6-24 ms).Parosmia(n=119;64.32%)was developed months after anosmia(3.05±1.87 ms).Objective testing showed anosmia in all,ageusia and flavor loss in 20%(n=37)and loss of nasal and oral trigeminal sensations in 18%(n=33)and 20%(n=37),*** had low scoring of sQOD-NS(11.41±3.66).There were no specific differences in other demographics and clinical variables which could distinguish post-COVID-19 smell and taste disorders in children from *** The course of small and taste disorders are supportive of the nasal and oral neuronal ***-COVID-19 taste and trigeminal disorders were less frequent compared to smell ***-COVID-19 flavor disorders were solely dependent on taste and not smell *** were no demographics,clinical variables at onset or specific profile of these disorders in children compared to adults.

关键词： Post-COVID-19 complications Anosmia Ageusia Trigeminal sensory loss Parosmia Quality of life

Green-synthetized selenium nanoparticles using berberine as a promising anticancer agent

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Journal of Integrative Medicine 2022年第1期20卷 65-72页

作者： mohamed S.Othman Sofian T.Obeidat Amal H.Al-Bagawi mohamed A.Fareid Alaa Fehaid ahmed E.Abdel Moneim Basic Sciences Department Deanship of Preparatory YearUniversity ofHa'ilHail 2240Saudi Arabia Faculty of Biotechnology October University for Modem Science and ArtsGiza 12451Egypt Chemistry Department Faculty of ScienceUniversity of Ha%Hail 2240Saudi Arabia Department of Botany and Microbiology Faculty of ScienceAl-Azhar UniversityCairo 35527Egypt Forensic Medicine and Toxicology Department Faculty of Veterinary MedicineMansoura UniversityDakahlia 35516Egypt Zoology and Entomology Department Faculty of ScienceHelwan UniversityCairo 11795Egypt

Objective: The chemo-preventative and therapeutic properties of selenium nanoparticles(Se NPs) have been documented over recent decades and suggest the potential uses of Se NPs in medicine. Biogenic Se NPs have higher biocompatibility and stability than chemically synthesized nanoparticles, which enhances their medical applications, especially in the field of cancer therapy. This study evaluated the potential of green-synthetized Se NPs by using berberine(Ber) as an antitumor agent and elucidated the mechanism by which these molecules combat Ehrlich solid tumors(ESTs).Methods: Se NPs containing Ber(Se NPs-Ber) were synthesized using Ber and Na2 Se O3 and characterized with Fourier transform infrared spectroscopy. Sixty male Swiss albino mice were then acclimatized for one week, injected with Ehrlich ascites tumor cells, and divided into four groups: EST, EST + cisplatin(5 mg/kg), EST + Ber(20 mg/kg), and EST + Se NPs-Ber(0.5 mg/kg). At the end of a 16-day observation period, 12 mice from each group were euthanized to analyze differences in the body weight, tumor size,gene expression, and oxidative stress markers in the four groups. Three mice from each group were kept alive to compare the survival ***: Treatment with Se NPs-Ber significantly improved the survival rate and decreased the body weight and tumor size, compared to the EST group. Se NPs-Ber reduced oxidative stress in tumor tissue,as indicated by a decrease in the lipid peroxidation and nitric oxide levels and an increase in the glutathione levels. Moreover, Se NPs-Ber activated an apoptotic cascade in the tumor cells by downregulating the B-cell lymphoma 2(Bcl-2) expression rate and upregulating the Bcl-2-associated X protein and caspase-3 expression rates. Se NPs-Ber also considerably improved the histopathological alterations in the developed tumor tissue, compared to the EST ***: Our study provides a new insight into the potential role of green-synthesized Se NPs by using Ber as

关键词： Selenium nanoparticles Berberine Ehrlich solid tumor Oxidative stress Apoptosis

An Efficient Text Recognition System from Complex Color Image for Helping the Visually Impaired Persons

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Computer Systems Science & Engineering 2023年第7期46卷 701-717页

作者： ahmed Ben Atitallah mohamed Amin Ben Atitallah Yahia Said Mohammed Albekairi Anis Boudabous Turki MAlanazi Khaled Kaaniche mohamed Atri Department of Electrical Engineering College of EngineeringJouf UniversitySakakaSaudi Arabia Laboratory of Informatics Gaspard-MongeA3SIESIEE ParisCNRSGustave Eiffel UniversityFrance LETI ENISUniversity of SfaxSfaxTunisia Remote Sensing Unit College of EngineeringNorthern Border UniversityArarSaudi Arabia Laboratory of Electronics and Microelectronics(LR99ES30) University of MonastirTunisia Department of Computer Engineering and Networks College of Computer and Information SciencesJouf UniversitySakakaSaudi Arabia College of Computer Sciences King Khalid UniversityAbhaSaudi Arabia

The challenge faced by the visually impaired persons in their day-today lives is to interpret text from *** this context,to help these people,the objective of this work is to develop an efficient text recognition system that allows the isolation,the extraction,and the recognition of text in the case of documents having a textured background,a degraded aspect of colors,and of poor quality,and to synthesize it into *** system basically consists of three algorithms:a text localization and detection algorithm based on mathematical morphology method(MMM);a text extraction algorithm based on the gamma correction method(GCM);and an optical character recognition(OCR)algorithm for text recognition.A detailed complexity study of the different blocks of this text recognition system has been *** this study,an acceleration of the GCM algorithm(AGCM)is *** AGCM algorithm has reduced the complexity in the text recognition system by 70%and kept the same quality of text recognition as that of the original *** assist visually impaired persons,a graphical interface of the entire text recognition chain has been developed,allowing the capture of images from a camera,rapid and intuitive visualization of the recognized text from this image,and text-to-speech *** text recognition system provides an improvement of 6.8%for the recognition rate and 7.6%for the F-measure relative to GCM and AGCM algorithms.

关键词： Text recognition system GCM AGCM OCR color images graphical interface