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Medical Image Compression Based on Wavelets with Particle Swarm Optimization

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Computers, Materials & Continua 2021年第5期67卷 1577-1593页

作者： Monagi h.Alkinani E.A.Zanaty sherif M.Ibrahim Department of Computer Science and Artificial Intelligence Faculty of Computer Science and EngineeringUniversity of JeddahJeddahSaudi Arabi Department of Computer Science Faculty of Computers and InformationSohag UniversitySohagEgypt Department of Computer Science and Mathematics Faculty of ScienceSouth Valley UniversityQenaEgypt

This paper presents a novel method utilizing wavelets with particle swarm optimization(PSO)for medical image *** method utilizes PSO to overcome the wavelets discontinuity which occurs when compressing images using *** transfers images into subband details and approximations using a modified haar wavelet(MhW),and then applies a *** is applied for selecting a particle assigned to the threshold values for the *** positions assigned to particles values are used to represent *** particle updates its position depending on the global best position(gbest)(for all details subband)and local best position(pbest)(for a subband).The fitness value is developed to terminate PSO when the difference between two local best(pbest)successors is smaller than a prescribe *** experiments are applied on five different medical image types,i.e.,MRI,CT,and *** show that the proposed algorithm can be more preferably to compress medical images than other existing wavelets techniques from peak signal to noise ratio(PSNR)and compression ratio(CR)points of views.

关键词： Image compression wavelets haar wavelet particle swarm algorithm medical image compression PSNR and CR

high temperature oxidation behavior of aluminide on a Ni-based single crystal superalloy in different surface orientations

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Progress in Natural Science:Materials International 2014年第2期24卷 163-170页

作者： Fahamsyah h.Latief Koji Kakehi El-Sayed M.sherif Department of Mechanical Engineering Tokyo Metropolitan University Center of Excellence for Research in Engineering Materials (CEREM) Advanced Manufacturing Institute King Saud University Electrochemistry and Corrosion Laboratory Department of Physical Chemistry National Research Centre (NRC)

An investigation on oxidation behavior of coated Ni-based single crystal superalloy in different surface orientations has been carried out at1100 ℃. It has been found that the {100} surface shows a better oxidation resistance than the {110} one, which is attributed that the {110}surface had a slightly higher oxidation rate when compared to the {100} surface. The experimental results also indicated that the anisotropic oxidation behavior took place even with a very small difference in the oxidation rates that was found between the two surfaces. The differences of the topologically close packed phase amount and its penetration depth between the two surfaces, including the ratio of α-Al2O3 after 500 h oxidation, were responsible for the oxidation anisotropy.

关键词： Ni-based superalloy Oxidation behavior Microstructure Aluminide coating Crystallographic orientation

Tailoring nanocomposite membranes of cellulose acetate/silica nanoparticles for desalination

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Journal of Materiomics 2022年第6期8卷 1122-1130页

作者： Amira S.Mohammed Ali Moataz M.Soliman sherif h.Kandil Shaker Ebrahim Marwa Khalil Materials Science Department Institute of Graduate Studies and Research(IGSR)Alexandria University163 Horrya AvenueEl-ShatbyP.O.Box 83221526AlexandriaEgypt Nanotechnology and Composite Materials Department Advanced Technology and New Materials Research InstituteCity of Scientific Research and Technological Applications(SRTA-City)P.O.Box 21934New Borg El Arab CityAlexandriaEgypt

herein, the fabrication of cellulose acetate (CA) silica-based nanocomposite membranes via the dry-wetphase inversion procedure for water desalination was investigated. The modified and unmodified silicananoparticles (MSNPs and SNPs) were prepared by the sol-gel technique. The effect of the SNPs andMSNPs was investigated on the CA membrane's properties and their performance for water *** CA nanocomposite membranes were characterized to study their structure, hydrophilicity, andmorphology. The fabricated nanocomposite membranes showed hydrophilic surface properties. Theperformance of reverse osmosis (RO) membranes was measured using a crossflow RO unit at 10 bar(1 bar = 0.1 MPa). The membrane with 10 mg of SNPs enhanced permeate water flux compared to thepristine CA membrane by 1.6 L/(m2·h). The effect of MSNPs on the nanocomposites' performance waslower than their counterpart in the case of adding SNPs. The membrane with 30 mg of MSNPs showedthe highest permeate water flux among other nanocomposite membranes with a value oAQSf 35.7 L/(m2·h)at 24 bar.

关键词： Silica nanoparticles Amino-modified silica Cellulose acetate Nanocomposite membrane Water desalination Reverse osmosis

Review of analytical methods for stress and deformation analysis of buried water pipes considering pipe-soil interaction

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Underground Space 2023年第6期13卷 205-227页

作者： Yingxu huo sherif Mohsen Mohamed hassan Gomaa Tarek Zayed Mohamed Meguid Department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityHung HomHong Kong 999077China Department of Building and Real Estate The Hong Kong Polytechnic UniversityHung HomHong Kong 999077China Structural Engineering Department Faculty of EngineeringMansoura UniversityMansoura 35516Egypt Department of Civil Engineering McGill UniversityMontrealQuebec H3A 0G4Canada

Buried water pipelines are vulnerable to fail or break due to excessive loading or ground *** evaluation of pipe performance and serviceability relies on the proper understanding of pipe-soil interactions(PSI).Analytical methods are important approaches to studying ***,a systematic and thorough literature review to analyze the existing research trends,technological achievements and future research opportunities is not *** work investigates analytical methods that analyze the stress and deformation of pipes in terms of cross-sectional,transverse and longitudinal PSI ***,scientometric analysis is performed to acquire relevant research works from online databases and analyze the existing data of influential authors,productive research sources and frequent key word occurrence in the fields of ***,a qualitative discussion is performed in the three categories of PSI:(1)cross-sectional,including ovalization and circumferential behaviours;(2)transverse,including seismic fault crossing,weak soil zones,ground settlement and pipe uplift;and(3)***,six research opportunities are discussed,including the role of friction in cross-sectional deformation,combined effects of bending and compression,choice of soil reaction models and calibration of key parameters,effect of pipe flaws,soil spatial variability and behaviours of curved *** study helps beginners familiarize themselves with PSI analytical methods and provides experienced researchers with ideas for future research directions.

关键词： Pipeline Analytical methods Pipe-soil interactions Seismic fault Settlement Uplift Buckling Tunnelling

Thrust characteristics of nano-carbon/Al/oxygenated salt nanothermites for micro-energetic applications

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Defence Technology（防务技术） 2023年第12期30卷 55-69页

作者： Ahmed Fahd Alex Baranovsky Charles Dubois Jamal Chaouki sherif Elbasuney Shady Shokry Chemical Engineering Department Ecole Polytechnique de MontrealMontrealH3C 3A7Canada Energetic Materials and Nanotechnology Research Center Technical Research CenterCairo11765Egypt Mechanical and Mechatronics Engineering Department University of WaterlooOntarioN2L 3G1Canada head of Nanotechnology Research Center Military Technical CollegeCairo11767Egypt Laser and Optoelectronics Research Center Technical Research CenterCairo11765Egypt

Combustion within small motors is key in the application-specific development of nanothermite-based micro-energetic systems. This study evaluates the performance of nanothermite mixtures in a converging-diverging nozzle and an open tube. Mixtures were prepared using nano-aluminum(n-Al),potassium perchlorate(KClO_(4)), and different carbon nanomaterials(CNMs) including graphene-oxide(GO), reduced GO, carbon nanotubes(CNTs) and nanofibers(CNFs). The mixtures were packed at different densities and ignited by laser beam. Performance was measured using thrust measurement,high-speed imaging, and computational fluid dynamics modeling, respectively. Thrust, specific impulse(ISP), volumetric impulse(ISV), as well as normalized energy were found to increase notably with CNM content. Two distinctive reaction regimes(fast and slow) were observed in combustion of low and high packing densities(20% and 55%TMD), respectively. Total impulse(IFT) and ISPwere maximized in the 5%GO/Al/KClO_4 mixture, producing 7.95 m N·s and 135.20 s respectively at 20%TMD, an improvement of 57%compared to a GO-free sample(5.05 m N·s and 85.88 s). CFD analysis of the motors over predicts the thrust generated but trends in nozzle layout and packing density agree with those observed experimentally;peak force was maximized by reducing packing density and using an open tube. The numerical force profiles fit better for the nozzle cases than the open tube scenarios due to the rapid nature of combustion. This study reveals the potential of GO in improving oxygenated salt-based nanothermites,and further demonstrates their applicability for micro-propulsion and micro-energetic applications.

关键词： Nanothermites Graphene oxide Reduced graphene oxide Carbon nano material Oxygenated salts Laser ignition Computational fluid dynamics

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Seismic hazard assessment of Western Coastal Province of Saudi Arabia:deterministic approach

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Earthquake Science 2016年第5期29卷 299-309页

作者： Faisal Rehman sherif M.El-hady Ali h.Atef hussein M.harbi Department of Earth Sciences University of SargodhaSargodhaPakistan Geophysics Department King Abdulaziz UniversityJeddahSaudi Arabia Earthquake Department National Research Institute ofAstronomy and GeophysicsHelwanEgypt

Seismic hazard assessment is carried out by utilizing deterministic approach to evaluate the maximum expected earthquake ground motions along the Western Coastal Province of Saudi Arabia. The analysis is accomplished by incorporating seismotectonic source model, determination of earthquake magnitude （Mmax）, set of appropriate ground motion predictive equations （GMPE）, and logic tree sequence. The logic tree sequence is built up to assign weight to ground motion scaling relationships. Contour maps of ground acceleration are generated at different spectral periods. These maps show that the largest ground motion values are emerged in northern and southern regions of the western coastal province in Saudi Arabia in comparison with the central region.

关键词： Earthquakes Seismic hazard Logic tree Peak ground acceleration

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Robust and high Accuracy Algorithm for Detection of Pupil Images

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Computers, Materials & Continua 2022年第10期73卷 33-50页

作者： Waleed El Nahal hatim G.Zaini Raghad h.Zaini sherif S.M.Ghoneim Ashraf Mohamed Ali hassan Electronics and Communications Engineering Department Faculty of EngineeringMSA UniversityCO12585Egypt Computer Engineering Department College of Computer and Information TechnologyTaif UniversityTaif21944Saudi Arabia Faculty of health and Rehabilitation Sciences Princess Nourah bint Abdulrahman UniversityRiyadhSaudi Arabia Department of Electrical Engineering College of EngineeringTaif UniversityTaif21944Saudi Arabia Electronics and Communications Engineering Department Faculty of EngineeringSinai UniversityArishCO45511Egypt

Recently,many researchers have tried to develop a robust,fast,and accurate *** algorithm is for eye-tracking and detecting pupil position in many applications such as head-mounted eye tracking,gaze-based human-computer interaction,medical applications(such as deaf and diabetes patients),and attention *** real-world conditions challenge the eye appearance,such as illumination,reflections,and *** the other hand,individual differences in eye physiology and other sources of noise,such as contact lenses or *** present work introduces a robust pupil detection algorithm with and higher accuracy than the previous attempts for real-time analytics *** proposed circular hough transform with morphing canny edge detection for Pupillometery(ChMCEP)algorithm can detect even the blurred or noisy images by using different filtering methods in the pre-processing or start phase to remove the blur and noise and finally the second filtering process before the circular hough transform for the center fitting to make sure better *** performance of the proposed ChMCEP algorithm was tested against recent pupil detection *** and results show that the proposed ChMCEP algorithm achieved detection rates of 87.11,78.54,58,and 78 according to´Swirski,ExCuSe,Else,and labeled pupils in the wild(LPW)data sets,*** results show that the proposed approach performs better than the other pupil detection methods by a large margin by providing exact and robust pupil positions on challenging ordinary eye pictures.

关键词： Pupil detection eye tracking pupil edge morphing techniques eye images dataset

Synthesis, spectral, optical and anti-inflammatory activity of complexes derived from 2-aminobenzohydrazide with some rare earths

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Journal of Rare Earths 2015年第7期33卷 758-764页

作者： Nasser Mohammed hosny El Sayed A.El Morsy Yousery E.sherif Chemistry Department Faculty of Science Port-Said University Clinical Pharmacology Department Faculty of Medicine Mansoura University Pharmacology and Therapeutics Department Qassim College of Medicine Qassim University Department of Chemistry Faculty of Science and Arts Taibah University

Three new metal complexes derived from Er（Ⅲ）, Dy（Ⅲ） and Zr（Ⅳ） with 2-aminobenzohydrazide （ABh） were synthesized and characterized by elemental analyses, IR, ^1h-NMR, ES-MS and transmission electron microscopy （TEM）. The morphology and the particle size were determined by TEM. The results showed that the ligand acted as neutral bi-dentate coordinating to the metal ions through the carbonyl oxygen and amidic amino nitrogen. The aromatic amine group remained inert towards coordination. The optical band gap was measured and found to be 3.3, 3.5 and 4.3 eV for Er（Ⅲ）, Dy（Ⅲ） and Zr（Ⅳ）, respectively. The optical band gap values indicated a semi-conducting nature of the investigated complexes. The anti-inflammatory and analgesic activities of the tested compounds were determined and compared with standard meloxicam.

关键词： Er(Ⅲ) Dy(Ⅲ) Zr(Ⅳ) metal complexes optical band gap rare earths

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Spot urinary sodium for assessing dietary sodium restriction in cirrhotic ascites

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World Journal of Gastroenterology 2009年第29期15卷 3631-3635页

作者： Mohammed Abdelhamid El-Bokl Bahaa Eldeen Senousy Khaled Zakaria El-Karmouty Inas El-Khedr Mohammed sherif Monier Mohammed sherif Sadek Shabana hassan Shalaby Department of Gastroenterology and hepatology Ain Shams University school of Medicine Abbassia 11566 Cairo Egypt

AIM： To evaluate the accuracy of spot urinary Na/K and Na/creatinine （Cr） ratios as an alternative to 24-h urinary sodium in monitoring dietary compliance in patients with liver cirrhosis and ascites treated with diuretics. METhODS： The study was carried on 40 patients with liver cirrhosis and ascites treated with diuretic therapy. Patients were divided into two groups according to 24-h urinary sodium. We measured spot urine Na/K ratio, Na/ Cr ratio and 24-h urinary sodium. Student＇s t test was used to compare the interval variables and x^2 test to compare the nominal variables between the two groups. Receiver operator characteristic curve was used to identify the best cutoff point for Na/K and Na/Cr ratio. RESULTS： The best cutoff point for Na/K ratio was 2.5 （P 〈 0.001） and area under the curve （AUC） was 0.9, and for Na/Cr ratio, the best cutoff point was 35 （P 〈 0.001） and AUC was 0.885. Na/K ratio showed higher sensitivity and accuracy compared to Na/Cr ratio （87.5% and 87% for Na/K ratio; 81% and 85% for Na/Cr ratio, respectively）. CONCLUSION： Spot urine Na/K ratio has adequate accuracy for assessment of dietary sodium restriction compared with 24-h urinary sodium in patients with liver cirrhosis and ascites.

关键词： Ascites Liver cirrhosis Portal hypertension Urinary sodium