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Connected Components-based Colour Image Representations of Vibrations for a Two-stage Fault Diagnosis of Roller Bearings Using Convolutional Neural Networks

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Chinese Journal of Mechanical Engineering 2021年第3期34卷 73-93页

作者： Hosameldin o.A.ahmed Asoke K Nandi Department of electronic and electrical Engineering Brunel University LondonUxbridge UB83PHUK School of Mechanical Engineering Xi’an Jiaotong UniversityXi’anChina

Roller bearing failure is one of the most common faults in rotating *** techniques for bearing fault diagnosis based on faults feature extraction have been *** feature extraction from fault signals requires expert prior information and human ***,deep learning algorithms have been applied extensively in the condition monitoring of rotating machines to learn features automatically from the input *** its robust performance in image recognition,the convolutional neural network(CNN)architecture has been widely used to learn automatically discriminative features from vibration images and classify health *** paper proposes and evaluates a two-stage method RGBVI-CNN for roller bearings fault *** first stage in the proposed method is to generate the RGB vibration images(RGBVIs)from the input vibration *** begin this process,first,the 1-D vibration signals were converted to 2-D grayscale vibration *** the conversion was completed,the regions of interest(RoI)were found in the converted 2-D grayscale vibration ***,to produce vibration images with more discriminative characteristics,an algorithm was applied to the 2-D grayscale vibration images to produce connected components-based RGB vibration images(RGBVIs)with sets of colours and texture *** the second stage,with these RGBVIs a CNN-based architecture was employed to learn automatically features from the RGBVIs and to classify bearing health *** cases of fault classification of rolling element bearings are used to validate the proposed *** results of this investigation demonstrate that RGBVI-CNN can generate advantageous health condition features from bearing vibration signals and classify the health conditions under different working loads with high ***,several classification models trained using RGBVI-CNN offered high performance in the testing results of the overall classification accura

关键词： Bearing fault diagnosis Image representation of vibrations Deep learning Convolutional neural networks

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Biological silicon nanoparticles improve Phaseolus vulgaris L. yield and minimize its contaminant contents on a heavy metals-contaminated saline soil

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Journal of Environmental Sciences 2021年第8期33卷 1-14页

作者： Mohamed T.el-Saadony el-Sayed M.Desoky ahmed M.Saad Rania S.M.Eid Eman Selem ahmed S.elrys Department of Agricultural Microbiology Faculty of AgricultureZagazig UniversityZagazig 44511Egypt Botany Department Faculty of AgricultureZagazig UniversityZagazig 44511Egypt Biochemistry Department Faculty of AgricultureZagazig UniversityZagazig 44511Egypt Agricultural Botany Department Faculty of AgricultureBenha University13736Egypt Botany and Microbiology Department Faculty of ScienceZagazig University44511Egypt Soil Science Department Faculty of AgricultureZagazig University44511ZagazigEgypt

The synthesis of biological silicon nano-particles(Bio-Si-NPs)is an eco-friendly and lowcost *** is no study focusing on the effect of Bio-Si-NPs on the plants grown on saline soil contaminated with heavy *** this study,an attempt was made to synthesis Bio-Si-NPs using potassium silica florid substrate,and the identified Aspergillus tubingensis AM11 isolate that separated from distribution systems of the potable water.A twoyear field trial was conducted to compare the protective effects of Bio-Si-NPs(2.5 and 5.0 mmol/L)and potassium silicate(10 mmol/L)as a foliar spray on the antioxidant defense system,physio-biochemical components,and the contaminants contents of Phaseolus vulgaris *** on saline soil contaminated with heavy *** findings showed that all treatments of Bio-Si-NPs and potassium silicate significantly improved plant growth and production,chlorophylls,carotenoids,transpiration rate,net photosynthetic rate,stomatal conductance,membrane stability index,relative water content,free proline,total soluble sugars,N,P,K,Ca2+,K+/Na+,and the activities of peroxidase,catalase,ascorbic peroxidase and superoxide oxide *** of Bio-Si-NPs and potassium silicate significantly decreased electrolyte leakage,malondialdehyde,H2 o2,o2·-,Na+,Pb,Cd,and Ni in leaves and pods of Phaseolus vulgaris *** to ***-Si-NPs were more effective compared to potassium *** of Bio-Si-NPs at the rate of 5 mmol/L was the recommended treatment to enhance the performance and reduce heavy metals content on plants grown on contaminated saline soils.

关键词： Bean Silicon Nano-silicon Aspergillus tubingensis AM11 Salinity Heavy metals

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Dolomite apatite separation by amphoteric collector in presence of bacteria

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Journal of Central South University 2013年第6期20卷 1645-1652页

作者： elmahdy ahmed el-Mofty Salah Abdel-Khalek Mohamed Abdel-Khalek Nagui el-MidanyAyman Central Metallurgical Research and Development Institute Mining Petroleum and Metallurgical Engineering DepartmentCairo University

Bioflotation represents one of the growing trends to enhance the selectivity of conventional flotation processes. It utilizes the micro-organisms to replace or to interact with the chemical reagents to increase the gap between surface properties of similar minerals and to enhance the separation selectivity. In this work, dolomite-phosphate separation was investigated using amphoteric collector （dodecyl-N-carboxyethyl-N-hyroxyethyl-imidazoline） in presence of bacteria. Two types of bacteria, Corynebacterium- diphtheriae-intermedius （CDI）, and Pseudomonas aeruginosa （PA）, were used. The collector-bacteria interaction was characterized by Fourier transform infra-red （FTIR）, frothing height and Zeta potential. The results show that the collector-bacteria interaction improves the flotation selectivity. Although, the PA positively affects the separation results, the CDI cannot lower the Mgo to less than 1%. A phosphate content of 0.7% Mgo and 31.77% P205 with a recovery of 68% at pH 11, 3.0 kg/t amphoteric collector, 4× 10^7 cells of PA is obtained.

关键词： dolomite phosphate amphoteric collector bacteria bio-flotation carbonate minerals

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Controlled drainage in the Nile River delta of Egypt:a promising approach for decreasing drainage off-site effects and enhancing yield and water use efficiency of wheat

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Journal of Arid Land 2023年第4期15卷 460-476页

作者： Mohamed K el-GHANNAM Fatma WASSAR Sabah MoRSY Mohamed HAFEZ Chiter M PARIHAR Kent o BURKEY ahmed M ABDALLAH Soil Water and Environment Research InstituteAgricultural Research CenterGiza 12112Egypt Higher Institute of Water Sciences and Techniques of Gabès University of GabèsGabès 6072Tunisia Institute of Arid Regions Medenine 4119Tunisia Crop Science Department Faculty of AgricultureDamanhour UniversityDamanhour 22516Egypt Land and Water Technologies Department Arid Lands Cultivation Research InstituteCity of Scientific Research and Technological ApplicationsNew Borg El-Arab 21934Egypt Indian Council of Agricultural Research(ICAR)-Indian Agricultural Research Institute(IARI) New Delhi 110012India United States Department of Agriculture(USDA)-Agricultural Research Services(ARS) Plant Science Research UnitNorth Carolina 27607USA Natural Resources and Agricultural Engineering Department Faculty of AgricultureDamanhour UniversityDamanhour 22516Egypt

North Africa is one of the most regions impacted by water *** implementation of controlled drainage(CD)in the northern Nile River delta of Egypt is one strategy to decrease irrigation,thus alleviating the negative impact of water *** study investigated the impacts of CD at different levels on drainage outflow,water table level,nitrate loss,grain yield,and water use efficiency(WUE)of various wheat *** levels of CD,i.e.,0.4 m below the soil surface(CD-0.4)and 0.8 m below the soil surface(CD-0.8),were compared with subsurface free drainage(SFD)at 1.2 m below the soil surface(SFD-1.2).Under each drainage treatment,four wheat cultivars were grown for two growing seasons(November 2018–April 2019 and November 2019–April 2020).Compared with SFD-1.2,CD-0.4 and CD-0.8 decreased irrigation water by 42.0%and 19.9%,drainage outflow by 40.3%and 27.3%,and nitrate loss by 35.3%and 20.8%,*** CD treatments,plants absorbed a significant portion of their evapotranspiration from shallow groundwater(22.0%and 8.0%for CD-0.4 and CD-0.8,respectively).All wheat cultivars positively responded to CD treatments,and the highest grain yield and straw yield were obtained under CD-0.4 *** the initial soil salinity as a reference,the soil salinity under CD-0.4 treatment increased two-fold by the end of the second growing season without negative impacts on wheat *** the drainage system by raising the outlet elevation and considering shallow groundwater contribution to crop evapotranspiration promoted water-saving and *** responses could be obtained based on the different plant tolerance to salinity and water stress,crop characteristics,and growth ***-specific soil salinity management practices will be required to avoid soil salinization due to the adoption of long-term shallow groundwater in Egypt and other similar agroecosystems.

关键词： drainage ratio nitrate loss water use efficiency yield soil salinity Nile River delta

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Mafic and felsic magmatism in the Wadi Kalalat area, South Eastern Desert, Egypt: mineralogy, geochemistry and geodynamic evolution during the Neoproterozoic in the Nubian Shield

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Acta Geochimica 2024年第1期43卷 150-173页

作者： Adel A.Surour ahmed A.Madani Mohamed A.el-Sobky Faculty of Science Galala UniversityNew Galala CitySuez 43511Egypt Department of Geology Faculty of ScienceCairo UniversityGiza 12613Egypt Egyptian Mineral Resources Authority P.O.Box 11517AbbasiyaCairoEgypt

In the south Eastern Desert of Egypt,two contrasting types of magmatism(mafic and felsic) are recorded in the Wadi Kalalat area,and form the Gabal el Motaghiarat and Gabal Batuga intrusions,*** two intrusions post-dates ophiolitic and arc associations represented by serpentinite and metagabbro-diorite,*** mafic intrusion has a basal ultramafic member represented by fresh peridotite,which is followed upward by olivine gabbro and anorthositic or *** mafic intrusion pertains to the Alaskan-type mafic-ultramafic intrusions in the Arabian-Nubian Shield(ANS)being of tholeiitic nature and emplaced in a typical arc *** the other hand,the Gabal Batuga intrusion comprises three varieties of fresh A-type granites of high K-calc alkaline nature,which is peraluminous and garnetbearing in parts.A narrow thermal aureole in the olivine gabbro of the mafic intrusion was developed due to the intrusion of the Batuga *** results in the development of a hornfelsic melagabbro variety in which the composition changed from tholeiitic to a calc-alkaline composition due to the addition of S_(i)o_(2),Al_(2)o_(3),alkalis,lithosphile elements(LILEs) such as Rb(70 ppm) and Y(28 ppm) from the felsic *** the thermal aureole,Rb amounts 2-8 ppm and Y lies in the range elieved that the Gabal Batuga felsic intrusion started to emplace during the waning stage of an arc system,with transition from the pre-collisional(i.e.,arc setting) to post-collisional and within plate *** from which the Gabal Batuga granites were fractionated is high-K calc-alkaline giving rise to a typical post-collisional A-type granite(A_(2)-subtype) indicating an origin from an underplating crustal ***,it is stressed here that the younger granites in the ANS are not exclusively post-collisional and within-plate but most likely they started to develop before closure of the arc *** possible source(s) of mafic magmas

关键词： Wadi Kalalat Gabal el Motaghairat mafic intrusion Gabal Batuga felsic intrusion Arc setting Post-collision Within-plate

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Preparation and characterization of (Ceo2)x-(Fe2o3)1-x nanocomposites:reduction kinetics and hydrogen storage

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Rare Metals 2020年第3期39卷 218-229页

作者： Shimaa G.Sayed Waleed M.A.el Rouby ahmed A.Farghali Materials Science and Nanotechnology Department Faculty of Postgraduate Studies for Advanced Science(PSAS)Beni-Suef UniversityBeni Suef62511Egypt

A series of nanosized Ceo2-Fe2o3 mixed-oxide nanocomposites with different Ce4+/Fe3+molar ratios were successfully prepared by a co-precipitation *** surface area increased with Fe2o3 content increasing up to 60 wt%in the ***,with further increase in Fe2o3 content,the surface area began to *** reduction processes of the Ceo2-Fe2o3 nanocomposites were studied in a hydrogen atmosphere at 300-600℃.The reduction rates increased by increasing both the temperature and Fe2o3 content in the *** microstructure of the reduced composites at 500℃illustrated the presence of a considerable number of macro-and *** activation energy values were calculated which were in the range of 3.56-5.37 kJ mol-1 at the initial stages(up to 35%reduction)and 5.21-10.2 kJ·mol-1 at the final stages(up to 80%reduction)of *** rate-controlling mechanisms in both the initial and final reduction stages were determined,and the initial reaction stage was controlled by combined gaseous diffusion and interfacial chemical reaction mechanisms for all the composites except for pure Ceo2,which was controlled by a chemical reaction *** final reaction stage was controlled by a gaseous diffusion mechanism for some composites,while for the others it was controlled by combined gaseous diffusion and interfacial chemical reaction *** hydrogen sorption properties of the nanocomposites were studied by pressure composition isotherms using a volumetric *** storage in the nanocomposites increased by increasing the temperature because of the formation of oxygen vacancies which enhance atomic H adsorption and function as strong adsorption sites forming more metal hydride covalent bonds.

关键词： Ceo2-Fe2o3 nanocomposite Reduction kinetics Reduction mechanism Hydrogen storage oxygen vacancies

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Trends and outcomes of pancreaticoduodenectomy for periampullary tumors: A 25-year single-center study of 1000 consecutive cases

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World Journal of Gastroenterology 2017年第38期23卷 7025-7036页

作者： ayman el nakeeb waleed askar ehab atef ehab el hanafy ahmad m sultan tarek salah ahmed shehta mohamed el sorogy emad hamdy mohamed el hemly ahmed a el-geidi tharwat kandil mohamed el shobari talaat abd allah amgad fouad mostafa abu zeid ahmed abu el eneen nabil gad el-hak gamal el ebidy omar fathy ahmed sultan mohamed abdel wahab gastroenterology surgical center mansoura university

AIM To evaluate the evolution, trends in surgical approaches a n d r e c o n s t r u c t i o n t e c h n i q u e s, a n d i m p o r t a n t lessons learned from performing 1000 consecutive pancreaticoduodenectomies(PDs) for periampullary *** This is a retrospective review of the data of all patients who underwent PD for periampullary tumor during the period from January 1993 to April 2017. The data were categorized into three periods, including early period(1993-2002), middle period(2003-2012), and late period(2013-2017).RESULTS The frequency showed PD was increasingly performed after the year 2000. With time, elderly, cirrhotic and obese patients, as well as patients with uncinate process carcinoma and borderline tumor were increasingly selected for PD. The median operative time and postoperative hospital stay decreased significantly over the periods. Hospital mortality declined significantly, from 6.6% to 3.1%. Postoperative complications significantly decreased, from 40% to 27.9%. There was significant decrease in postoperative pancreatic fistula in the second 10 years, from 15% to 12.7%. There was a significant improvement in median survival and overall survival among the *** Surgical results of PD significantly improved, with mortality rate nearly reaching 3%. Pancreatic reconstruction following PD is still debatable. The survival rate was also improved but the rate of recurrence is still high, at 36.9%.

关键词： Pancreaticoduodenectomy Pancreaticogastrostomy Pancreaticojejunostomy Postoperative pancreatic fistula Periampullary tumor

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Geochemistry of lamprophyre dykes, Wadi Sikait area, South Eastern Desert, Egypt

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Chinese Journal of Geochemistry 2011年第3期30卷 323-331页

作者： Ibrahim M.el-Ahmadi Ragab A.ahmed Nuclear Materials Authority el-Maadi P.o.Box 530 Cairo Egypt

The Wadi Sikait area lies at about 95 km southwest of Marsa Alam City along the Red Sea Coast, Eastern Desert, Egypt. It is occupied by Precambrian rocks of ophiolitic mélange, metamorphosed sandstones (MSS), gab-bros and monzogranites which were later intruded by lamprophyre dykes and quartz veins. The lamprophyre dykes were extruded in NW-SE and NE-SW trends cutting monzogranites and metamor-phosed sandstones. The lamprophyres are porphyritic and composed of clinopyroxene, olivine and amphibole phenocrysts enclosed in a fine-grained groundmass of clinopyroxene, amphibole, opaque and lithium mica. The al-teration products are represented by amphibole (tremolite-actinolite and hornblende), carbonate, epidote, chlorite, iddingsite, clay minerals, limonite and serpentine. The Sikait lamprophyre dykes can be classified as alkaline lamprophyres characterized by silica contents rang-ing from 41.65 wt% to 50.88 wt% and Na2o>K2o. They are enriched in LILE, LREE and HFSE, but strongly de-pleted in compatible elements such as Cr and Ni relative to the primitive mantle. Sikait lamprophyres have moderate Zr/Hf (35.6-52.8) and Nb/Ta (20.5-22.5) ratios. Most of these features are attributed to the origin of these dykes from the metasomatized mantle affected by subduction-related fluid. These lamprophyres are compositionally similar to Salu lamprophyres in eastern China. The Sikait lamprophyre samples have high LREE (320×10-6-419×10-6) relative to HREE (20×10-6-33×10-6) with ratios (LREE/HREE=11.6-18.7) and no negative Eu anomaly (Eu/Eu*=0.9-1.04). The relative presence of posi-tive Ce anomaly (Ce/Ce*=1.04) in lamprophyre samples suggests the oxidizing condition under which the REEs were precipitated due to the common occurrence of fluorite and apatite.

关键词：煌斑岩地球化学特征岩脉沙漠埃及二长花岗岩单斜辉石蛇绿混杂岩

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Effect of Cuo Addition on the Sintering Behavior and electrical Conductivity of 3Y-TZP

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Journal of Materials Science & Technology 2007年第1期23卷 131-134页

作者： ahmed A.Hassan omar Abdelal A. S.M.el-Hout Dept. of Metallurgy Nuclear Research CenterAtomic Energy AuthorityCairoEgypt

Yttria stabilized tetragonal zirconia polycrystals （3Y-TZP） doped with Cuo was prepared, to get two compositions, 0.3 and 1 mole fraction Cuo, respectively. The dilatometric study of the samples showed sintering to be improved for the samples doped with 0.3 mole fraction Cuo, and to be deteriorated for the samples doped with 1 mole fraction Cuo. The 1 mole fraction Cuo doped 3Y-TZP showed higher tetragonal/monoclinic phase transformation which was accompanied by grain growth. The electrical conductivity decreased with the addition of Cuo.

关键词： Y2o3 Sintering aids electrical conductivity Fuel cells

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Egyptian heavy vacuum gas oil hydrotreating over Co-Mo/CNT and Co-Mo/γ-Al2o3 catalysts

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燃料化学学报 2016年第7期44卷 853-861页

作者： W.ahmed Hoda,S.ahmed H.S.el-Sheshtawy Nadia,A.Mohamed Asmaa,I.Zahran Egyptian Petroleum Research Institute 1Aahmed El-Zomor st.Naser city 11727CairoEgypt Ain-Shams University for Girls Roqqsy SquireCairoEgypt

The catalytic activity of CoMoS /CNT towards the Egyptian heavy vacuum gas oil hydrotreating was studied. The delivered CNT was functionalized with 6 mol /L HNo_3. The CNT were loaded with 12% Moo_3( by weight) and 0.7 Co /Mo atomic ratio with impregnation methods. The γ-Al_2o_3 catalyst was also prepared by impregnation method to compare both catalysts *** analysis tools such XRD,Raman spectroscopy,TEM,and BET were used to characterize the catalysts. The autoclave reactor was used to operate the hydrotreating experiments. The hydrotreating reactions were tested at various operating conditions of temperature 325-375 ℃,pressure 2-6 MPa,time 2-6 h,and catalyst /oil ratio( by weight) of 1 ∶75,1 ∶33 and 1 ∶10. The results revealed that the CoMoS /CNT was highly efficient for the hydrotreating more than the CoMoS /γ-Al_2o_3. Also, the hydrodesulfurization( HDS) increased with increasing catalyst /oil ratio. Additionally,results showed that the optimum condition was temperature 350℃,pressure 4 MPa,catalyst /oil ratio of 1 ∶75 for 2 h. Furthermore,even at low CoMoS /CNT catalyst /oil ratio of 1 ∶75,an acceptable HDS of 77.1% was achieved.

关键词： hydrotreatment hydrodesulfurization carbon nanotube heavy vacuum gas oil(HVGo)

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