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PVC nanocomposites for cable insulation with enhanced dielectric properties,partial discharge resistance and mechanical performance

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High Voltage 2020年第4期5卷 463-471页

作者： Nagat M.K.Abdel-Gawad adel Z.El Dein Diaa-Eldin A.Mansour Hanaa M.Ahmed mohamed M.F.Darwish Matti Lehtonen Department of Electrical Power and Machines Engineering Faculty of Engineering at ShoubraBenha UniversityCairoEgypt Department of High Voltage Networks Faculty of Energy EngineeringAswan UniversityAswanEgypt High Voltage and Superconductivity Laboratory Department of Electrical Power and Machines EngineeringFaculty of EngineeringTanta UniversityTantaEgypt Department of Mathematics and Engineering Physics Faculty of Engineering at ShoubraBenha UniversityCairoEgypt Department of Electrical Engineering and Automation School of Electrical EngineeringAalto UniversityEspooFinland

The current study aims to develop polyvinyl chloride(PVC)nanocomposites with enhanced electrical and mechanical properties by incorporating titanium oxide(TiO_(2))nanoparticles within PVC *** loading of nanoparticles and different nanoparticle surface states were *** surface states are unfunctionalised,functionalised using vinyl silane and functionalised using amino *** choice of a most suitable surface state was a critical factor that guarantees a good dispersion of nanoparticles and consequently enhances the compatibility between TiO_(2)and PVC *** process followed in the PVC/TiO_(2)nanocomposites preparation,loaded with different wt.%of TiO_(2)nanoparticles,was the solvent *** dielectric properties measured here were the relative permittivity(ɛr),dielectric loss(tanδ),breakdown strength(AC and DC under uniform field)and the internal partial discharges(PDs)within insulation *** measurements have been performed under room temperature and at frequency ranged from 20 to 1.0 ***,the mechanical properties of the samples like elongation,elasticity modulus and tensile strength were also *** silane showed better improvements in both electrical and mechanical performances compared to the amino silane,especially in cases of high weight fractions of TiO_(2).This is because of the improvement in the PVC-TiO_(2)interfacial region arise from the similarity of polarity and surface tension values of vinyl silane with that of PVC matrix and TiO_(2)nanoparticles.

关键词： dielectric insulation resistance

A Survey of SQL Injection Attack Detection and Prevention

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Journal of Computer and Communications 2014年第8期2卷 1-9页

作者： Khaled Elshazly Yasser Fouad mohamed Saleh adel Sewisy Assistant Professor Head of Department of Mathematics Faculty of Science Suez University Suez Egypt Demonstrator of Computer Science Information System Institute Suez Egypt Lecturer of Computer Science Faculty of Science Suez University Suez Egypt Professor of Computer Science Faculty of Computers & Information Assiut University Assiut Egypt

Structured Query Language Injection Attack (SQLIA) is the most exposed to attack on the Internet. From this attack, the attacker can take control of the database therefore be able to interpolate the data from the database server for the website. Hence, the big challenge became to secure such website against attack via the Internet. We have presented different types of attack methods and prevention techniques of SQLIA which were used to aid the design and implementation of our model. In the paper, work is separated into two parts. The first aims to put SQLIA into perspective by outlining some of the materials and researches that have already been completed. The section suggesting methods of mitigating SQLIA aims to clarify some misconceptions about SQLIA prevention and provides some useful tips to software developers and database administrators. The second details the creation of a filtering proxy server used to prevent a SQL injection attack and analyses the performance impact of the filtering process on web application.

关键词： SQL Injection Database Security Attack Authentication

Y-Shaped Intra-Scleral Fixated Lens versus Retro-Pupillary Iris Claw Lens in the Treatment of Aphakia

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Open Journal of Ophthalmology 2019年第2期9卷 105-124页

作者： Ahmed mohamed Morshed Mahmoud Nasr Aldeeb adel Kamal Abdeen Salah mohamed Almosalamy Ophthalmology Department Faculty of Medicine Zagazig University Zagazig Egypt

Background: Many reasons can lead to an aphakia without adequate capsular support for implantation of a posterior chamber intraocular lens (IOL), such as intraoperative unintentional rupture of posterior capsule during phacoemulsification, planned intracapsular cataract extraction, ocular trauma and lens dislocation due to congenital and acquired causes. Purpose: To compare Y-shaped intra-scleral fixation of a posterior chamber IOL with retro pupillary fixation of an iris-claw intraocular lens (IOL) for Aphakic eyes without sufficient capsular support as respects safety, visual recovery and complications of both methods. Patients and Methods: One hundred Aphakic eyes were arbitrarily distributed between two groups. Group A included 50 eyes treated with retropupillary fixation of iris claw lens and group B included 50 eyes treated with Y-shaped intra-scleral fixation technique. Preoperative, intraoperative and postoperative data were analysed including best corrected visual acuity (BCVA), intraocular pressure (IOP), surgical time, intraoperative problems, IOL malposition and postoperative complications. Following up on patients was carried out for at least six months. Results: The mean duration of surgery was 21 ± 5.3 min in group A and was 53.4 ± 6.9 min in group B (p-value 0.05). IOL tilt was found in 0 (0%) eyes in group A and in 5 (10%) eyes in group B (p 0.05). Conclusion: The results of our study indicated that both methods are satisfactory in correcting aphakia without sufficient capsular support as regards postoperative best corrected visual acuity (BCVA);however the surgical technique of retropupillary iris claw lens is easier, shorter, with low intra- and postoperative complications and safer than those used for intra-scleral fixation of IOL. But for eyes which lack both iris and capsular support, a scleral fixation of a posterior chamber IOL remains the only option.

关键词： Aphakia Iris-Claw Intraocular Lens (IOL) Y-Shaped Intra Scleral Fixation

Thermal Stability and Degradation of Chitosan Modified by Cinnamic Acid

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Open Journal of Polymer Chemistry 2012年第1期2卷 14-20页

作者： Mostafa Amin Diab adel Zak El-Sonbati mohamed mohamed Al-Halawany Dina mohamed Diaa Bader Chemistry Department Faculty of Science Mansoura University Damietta Egypt Engineering Mathematics and Physics Department Faculty of Engineering Mansoura University Mansoura Egypt

The reaction of chitosan with cinnamic acid gave the corresponding N-cinnamoyl chitosan (NCC) polymer. The chem-ical structure of the modified polymer was characterized by IR, 1H-NMR and elemental analysis. Thermogravim- etric analysis reveals that the thermal stability of chitosan polymer is greater than NCC polymer. The activation energies of thermal degradation of chitosan and NCC polymers were determined using Arrhenius relationship. Thermal degradation of NCC polymer was studied and the products of degradation were identified by GC-MS technique. It seems that the mechanism of degradation of NCC polymer is characterized by elimination of low-molecular weight radicals. Combination of these radicals and random scission mechanism along the backbone chain are the main source of the degradation products.

关键词： N-Cinnamoyl Chitosan Preparation Thermal Stability and Degradation Mechanism of Degradation

Rice(Oryza sativa L.)Breeding among Hassawi Landrace and Egyptian Genotypes for Stem Borer(Chilo agamemnon Bles.)Resistance and Related Quantitative Traits

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Phyton-International Journal of Experimental Botany 2022年第9期91卷 1905-1922页

作者： Mohammed I.Al-Daej mohamed M.El-Malky Muhammad N.Sattar adel A.Rezk Muhammad N.Naqqash Jameel M.Al-Khayri Department of Agricultural Biotechnology College of Agriculture and Food SciencesKing Faisal UniversityAl-Ahsa31982Saudi Arabia Rice Research and Training Center Field Crops Research InstituteAgricultural Research CenterKafrelsheikh33717Egypt Central Laboratories King Faisal UniversityAl-Ahsa31982Saudi Arabia Department of Virus and Phytoplasma Plant Pathology InstituteAgricultural Research Center(ARC)Giza12619Egypt Institute of Plant Protection University of AgricultureMultan66000Pakistan

Rice stem borer(Chilo agamemnon Bles.)is a primary insect pest of rice and is a major limiting factor to rice *** for insect-resistant crop varieties has been an economic way of integrated pest management(IPM)as it offers a viable and ecologically acceptable *** study was aimed to evaluate rice genotypes for their resistance against rice stem *** parental genotypes with twenty one F1 crosses were evaluated for genotypic variation in field *** of variance revealed significant differences for the studied traits in almost all crosses and *** addition,the mean squares of parents versus their crosses were signifi-cant for stem borer resistance and other associated ***,both general combining ability(GCA)and specific combining ability(SCA)variances were highly significant for all characters studied in the F1 *** on GCA,4 genotypes(Sakha101,Gz6903-3-4-2-1,Gz9577-4-1-1 and Hassawi)exhibited highly significant negative values for stem borer resistance(–0.53,–1.06,–0.18 and–0.49,respectively)indicating they are the best combiners for stem borer *** on SCA analysis,nine cross combinations showed highly significant negative effects for stem borer ***,the cross Giza178Hassawi was the best combination with significantly highest value for early *** addition,seven crosses showed highly significant negative SCA for plant height *** the other hand,for panicle length,number of primary branches/panicle,panicle weight and 1000-grain weight,seven,four,eight and six crosses showed highly significant positive SCA,*** result further revealed that the non-additive dominance genetic variance was higher than the additive variance for all evaluated traits indicating that non-additive genetic variances have a role in their *** broad-sense heritability estimates were high for all the studied *** stem borer resistance was significantly correl

关键词： Rice stem borer(Chilo agamemnon Bles.) general combining ability genetic parameters correlation coefficient principle component analysis

Impact of biomass in Egypt on climate change

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Natural Science 2013年第6期5卷 678-684页

作者： Dalia adel Nakhla mohamed Galal Hassan Salah El Haggar Department of Mechanical Engineering School of Sciences and Engineering The American University in Cairo Cairo Egypt Department of Petroleum Engineering School of Sciences and Engineering The American University in Cairo Cairo Egypt Environmental Engineering PhD Program School of Sciences and Engineering The American University in Cairo Cairo Egypt

Egypt is one of the most vulnerable countries to climate change due to the expected detrimental impacts on coastal zones, agriculture, water security as well as indirect social and health impacts. Egypt is responsible for 0.57% of the global greenhouse gas (GHG) emissions. Although Egypt is a non-annex I country not requiring any specific emission reduction or limitation targets under the Kyoto protocol, its National plans have included mitigation measures to reduce its greenhouse gases. The main sectors contributing to climate change in Egypt are energy, industry, agriculture and waste. Waste, on the other hand, has been accumulating in the streets of Egypt and along its water banks causing considerable air, soil and water pollution and indirect detrimental health impacts. However, this waste which is composed of organic municipal waste, agricultural residues, agro-industrial waste, animal manure and sewage sludge are valuable biomass resources. Utilizing the waste resources of Egypt especially the biomass or the organic component of this waste will not only solve some of the pressing economic needs of Egypt such as animal fodder, fertilizer and fuel but will also alleviate environmental burdens through decreasing air pollution and greenhouse gas emissions in the sector of waste as well as those of energy, industry and agriculture. This paper quantifies the biomass resources in Egypt generated from different waste resources. Then it demonstrates the efforts that Egypt made to contribute to global greenhouse gas emissions reductions through the Kyoto Protocol’s clean development mechanism (CDM). The projects in the waste sector already established in Egypt and approved as CDM projects are listed, which are related to waste management facilities and those which are waste to energy projects. Finally, a list of mitigation projects as proposed by the Egyptian government to decrease GHGs as related to the waste sector are enumerated.

关键词： Waste Climate Change Biomass Egypt

Robust Adaptive FTC against Sensor Fault

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Computer Technology and Application 2012年第1期3卷 56-68页

作者： Amina Challouf Christophe Aubrun adel Tellili mohamed Naceur Abdelkrim Unite de Recherche. Modelisation Analyse et Commande de Systemes （MACS） Ecole Nationale d＇Ingenieurs de Gabes （ENIG） Facultes des Sciences et Techniques Centre de Recherche en Automatique de Nancy （CRAN） Nancy-University CNRS UMR 7039 France Institute Superieure des Etudes Technologiques de Djerba （ISET） Universite de Gabes Gabes 6029 Tunisia

This paper addresses the problem of robust Fault-Tolerant （FT） design for large-scale systems. This particular class constitutes complex system which can be decomposed into N-interconnected subsystems. Special attention is paid to two different design architectures of an Active Fault-Tolerant Control （AFTC）. An AFTCS is characterized by an online Fault Detection and Isolation （FDI） process and a control reconfiguration mechanism. As the AFTC system offers the possibility to choose different controllers, the controller may be the most appropriate choice for the faulty situation and obtaining better performance. The goal of each adaptive controller is to accommodate sensor anomalies. Continuous, Linear and Time Invariant （LTI） complex system with faulty sensors and external disturbances is proposed. This study focuses on two different internal structures of the system. In this paper the direct adaptive method based on feedback controller design is applied both centralized and decentralized architectures. The controller gain is updated online using an adaptive law which takes into account the estimation of the faults and the disturbances. Then from the both classes of systems structures the adaptation controller performances, in terms of stability and fault effect rejection capability, are studied and compared. The proposed techniques are finally evaluated in the light of a simulation for a centralized interconnected system that can be decomposed into N-subsystems with some strong interconnections.

关键词： Adaptive control centralized control complex system decentralized control fault-tolerant control (FTC),N-Interconnected subsystems robust control sensor failure.

Effect of Transcranial Direct Current Stimulation of Motor Cortex versus Insula Cortex on Chronic Post-Mastectomy Pain: Randomized Sham-Controlled Trial

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Open Journal of Anesthesiology 2023年第10期13卷 197-211页

作者： Shereen Mamdouh Kamal Khaled mohamed Fares Sahar Abdel-Baky mohamed Mohanad Ahmed mohamed Fatma adel El Sherif Anaesthesia Intensive Care and Pain Management Department South Egypt Cancer Institute Assiut University Assiut Egypt

Background: Transcranial direct current stimulation (tDCS) across cortical brain areas appears to improve various forms of pain, yet evidence of tDCS efficiency and ideal stimulation target is lacking. This study aimed to compare the add-on analgesic efficacy of concentric electrode transcranial direct current stimulation (CE-tDCS) stimulation over the primary motor cortex versus the insular cortex on the management of chronic postmastectomy pain. Method: Prospective randomized double-blind sham-controlled study enrolled eighty patients with chronic postmastectomy pain that were randomly assigned to four groups: active motor (AM), sham motor (SM), active insula (AI) and sham insula (SI) group, each received 5 sessions for 20-minute duration with 2 mA tDCS over the targeted area of the contralateral side of pain. Our primary outcome was VAS score, the secondary outcomes were VDS score, LANSS score and depression symptoms by HAM-D scores, assessment was done at 4 time points (prestimulation, after 5th session, 15th day and one month after the last session). Results: Both active tDCS groups (motor and insula) showed reduction of VAS (P Conclusion: Active tDCS stimulation either targeting the primary motor cortex or the insula cortex has add-on analgesic effect for controlling neuropathic chronic post mastectomy pain and the maximum effect was at 15 days after the last session.

关键词： Transcranial Direct Current Stimulation tDCS Postmastectomy Pain Motor Cortex Insular Cortex

Production of global land cover data-GLCNMO

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International Journal of Digital Earth 2011年第1期4卷 22-49页

作者： Ryutaro Tateishi Bayaer Uriyangqai Hussam Al-Bilbisi mohamed Aboel Ghar Javzandulam Tsend-Ayush Toshiyuki Kobayashi Alimujiang Kasimu Nguyen Thanh Hoan adel Shalaby Bayan Alsaaideh Tsevenge Enkhzaya Gegentana Hiroshi P.Sato Center for Environmental Remote Sensing(CEReS) Chiba UniversityChibaJapan College of Geographical Science Inner Mongolia Normal UniversityHuhhotChina Geography Department University of JordanAmmanJordan National Authority for Remote Sensing and Space Sciences(NARSS) CairoEgypt School of Computer and Information Technology Mongolian State University of EducationUlaanbaatarMongolia Institute of Geographical Science and Tourism Xinjiang Normal UniversityUrumqiChina Geographical Survey Institute TsukubaJapan

Global land cover is one of the fundamental contents of Digital *** Global Mapping project coordinated by the International Steering Committee for Global Mapping has produced a 1-km global land cover datasetGlobal Land Cover by National Mapping *** has 20 land cover classes defined using the Land Cover Classification *** them,14 classes were derived using supervised *** remaining six were classified independently:urban,tree open,mangrove,wetland,snow/ice,*** source data of this land cover mapping were eight periods of 16-day composite 7-band 1-km MODIS data of *** data for supervised classification were collected using Landsat images,MODIS NDVI seasonal change patterns,Google Earth,Virtual Earth,existing regional maps,and expert’s *** overall accuracy is 76.5%and the overall accuracy with the weight of the mapped area coverage is 81.2%.The data are available from the Global Mapping project website(http://***/).TheMODISdata used,land cover training data,and a list of existing regional maps are also available from the CEReS *** mapping attempt demonstrates that training/validation data accumulation from different mapping projects must be promoted to support future global land cover mapping.

关键词： land cover remote sensing Digital Earth training data