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fabrication, Microstructure, Thermal and Electrical Properties of Copper Heat Sink Composites

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Materials Sciences and Applications 2016年第9期7卷 542-561页

作者： walid Daoush Ahmed Swidan Gamal Abd El-Aziz mohamed Abdelhalim Department of Production Technology Faculty of Industrial Education Helwan University Cairo Egypt Present Address: Department of Chemistry Faculty of Science Al-Imam Muhammad Ibn Saud Islamic University Al Riyadh KSA Mechanical Department Ameeria Integrated Technical Cluster Cairo Egypt Mechanical Department Faculty of Industrial Education Suez University Suez Egypt

Copper as well as copper base composites reinforced with coated and uncoated 1 wt% diamond, graphite particles or short carbon fibers are prepared by powder metallurgy process. The reinforcement particles were encapsulated with silver as well as copper layer by using the electroless deposition technique to investigate the influence of the reinforcement surface coating on the microstructure, density, electrical and thermal properties of the sintered samples. The coated and the uncoated powders were cold compacted at 600 MPa, and then sintered at 1173 K (900°C) for 2 h under hydrogen atmosphere. The phase composition, morphology and microstructure of the prepared powders as well as the copper base sintered composites were investigated using X-ray diffraction analysis (XRD) and Scanning Electron Microscope (SEM) equipped with an Energy Dispersive Spectrometer (EDS) respectively. The density of the sintered composites was measured by Archimedes method. The copper base consolidated composites had a density up to 96% and the reinforcement coated particles were distributed uniformly within the copper matrix better than the uncoated one. The electrical resistivity at room temperature and the heat transfer conduction of the produced samples were measured in a temperature range between 323 K (50°C) and 393 K (120°C). The results observed that the sintered materials prepared from the coated powder have lower electrical resistivity than the sintered materials prepared from the mixed powders. On the other hand the thermal conductivity values were calculated using the heat transfer conduction values by means of the fourier formula. The results observed that the thermal conductivity of copper is (391 W/m·K), 1 wt% diamond/Cu is (408 W/m·K), 1 wt% graphite coated silver/Cu is (393 W/m·K), 1 wt% Cu coated short carbon fiber/Cu is (393 W/m·K), graphite/Cu is (383 W/m·K) and short carbon fiber/Cu is (382 W/m·K). The obtained compos

关键词： Heat Sink Powder Metallurgy Matrix Composites Electrical Resistivity Thermal Conductivity Natural forced Convection

Enhancing Early Detection of Lung Cancer through Advanced Image Processing Techniques and Deep Learning Architectures for CT Scans

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Computers, Materials & Continua 2024年第10期81卷 271-307页

作者： Nahed Tawfik Heba M.Emara walid El-Shafai Naglaa f.Soliman Abeer D.Algarni fathi EAbd El-Samie Computers and Systems Department Electronics Research InstituteEl NozhaHuckstep Cairo12622Egypt Department of Electronics and Electrical Communications Engineering Faculty of Electronic EngineeringMenoufia UniversityMenouf32952Egypt Security Engineering Lab Computer Science DepartmentPrince Sultan UniversityRiyadh11586Saudi Arabia Department of Information Technology College of Computer and Information SciencesPrincess Nourah bint Abdulrahman UniversityRiyadh84428Saudi Arabia

Lung cancer remains a major concern in modern oncology due to its high mortality rates and multifaceted origins,including hereditary factors and various clinical *** stands as the deadliest type of cancer and a significant cause of cancer-related deaths *** diagnosis enables healthcare providers to administer appropriate treatment measures promptly and accurately,leading to improved prognosis and higher survival *** significant increase in both the incidence and mortality rates of lung cancer,particularly its ranking as the second most prevalent cancer among women worldwide,underscores the need for comprehensive research into efficient screening *** in diagnostic techniques,particularly the use of computed tomography(CT)scans,have revolutionized the identification of lung *** scans are renowned for their ability to provide high-resolution images and are particularly effective in detecting small,calcified areas,crucial for identifying earlystage lung ***,there is growing interest in enhancing computer-aided detection(CAD)*** algorithms assist radiologists by reducing false-positive interpretations and improving the accuracy of early cancer *** study aims to enhance the effectiveness of CAD systems through various ***,the Contrast Limited Adaptive Histogram Equalization(CLAHE)algorithm is employed to preprocess CT scan images,thereby improving their visual *** refinement is achieved by integrating different optimization strategies with the CLAHE *** CutMix data augmentation technique is applied to boost the performance of the proposed model.A comparative analysis is conducted using deep learning architectures such as InceptionV3,ResNet101,Xception,and *** study evaluates the performance of these architectures in image classification tasks,both with and without the implementation of the CLAHE *** empirical findings of the study demonst

关键词： Lung cancer detection CLAHE algorithm optimization deep learning classification feature extraction healthcare applications

The Impact of Marine Water on Different Types of Coarse Aggregate of Geopolymer Concrete

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Journal of Minerals and Materials Characterization and Engineering 2019年第5期7卷 330-353页

作者： Shimaa Younis Megahed Abolwafa Mohamad Elthakeb walid Alsayed mohamed Mohammed Taha Nooman walid Hessian Soufy fayoum future Institute Fayoum Egypt Department of Reinforced Concrete Faculty of Engineering Al-Azhar University Cairo Egypt Department of Irrigation and Hydraulics Faculty of Engineering Al-Azhar University Cairo Egypt Department of Properties and Strength of Material Civil Engineering Faculty of Engineering Al-Azhar University Cairo Egypt Housing and Building National Research Center (HBRC) Cairo Egypt

This research studies the impact of different types of coarse aggregate on the behavior of geopolymer concrete based on both fly ash (fA) and ground granulated blast furnace slag (GGBfS) in different marine environments. Aiming to solve the problems caused by the construction and demolition waste and the depletion of natural aggregates, in the present study coarse recycled aggregates is used to produce new green concrete with a fly ash-slag based geopolymer. By this examination, the research seeks to improve the quality and productivity of concrete used in construction and hydraulic projects. for this research, four mixtures containing different types of coarse aggregate in two different water environments were used. The utilized mixtures contained natural aggregate concrete (NAC) such as basalt and crushed marble. Also, recycled coarse aggregate concrete (RAC), which totally replaced natural aggregate, was presented in this paper such as crushed concrete and crushed ceramic. for this study, in the sieve analysis;specific and unit weights, was recorded. furthermore, the mechanical properties were determined, using a compressive test that was conducted on the 7th, 28th, 56th and 90th days at different water environments;potable water (PW) and sea water (SW). Durability test was also performed for total absorption measurement. Results indicated that geopolymer concrete exhibits better strength in marine environments than in those of potable water. Results also showed that crushed marble (CMA) exhibits higher compressive strength and durability.

关键词： Geopolymer Concrete fly Ash Ground Granulated Blast furnace Slag (GGBfS) Sea Water Natural Aggregate Concrete Recycled Concrete Aggregate Compressive Strength and Durability

Efficient forgery Detection Approaches for Digital Color Images

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Computers, Materials & Continua 2022年第5期71卷 3257-3276页

作者： Amira Baumy Abeer D.Algarni Mahmoud Abdalla walid El-Shafai fathi E.Abd El-Samie Naglaa f.Soliman Department of Communications High Institute for Engineering and TechnologyAl-Obour Obour CityEgypt Department of Information Technology College of Computer and Information SciencesPrincess Nourah Bint Abdulrahman UniversityRiyadhSaudi Arabia Department of Electronics and Communications Engineering Faculty of EngineeringZagazig UniversityZagazigSharqia44519Egypt Department of Electronics and Electrical Communications Engineering Faculty of Electronic EngineeringMenoufia UniversityMenoufia32952Egypt Security Engineering Lab Computer Science DepartmentPrince Sultan UniversityRiyadh11586Saudi Arabia

This paper is concerned with a vital topic in image processing:color image forgery detection. The development of computing capabilitieshas led to a breakthrough in hacking and forgery attacks on signal, image,and data communicated over networks. Hence, there is an urgent need fordeveloping efficient image forgery detection algorithms. Two main types offorgery are considered in this paper: splicing and copy-move. Splicing isperformed by inserting a part of an image into another image. On the otherhand, copy-move forgery is performed by copying a part of the image intoanother position in the same image. The proposed approach for splicingdetection is based on the assumption that illumination between the originaland tampered images is different. To detect the difference between the originaland tampered images, the homomorphic transform separates the illuminationcomponent from the reflectance component. The illumination histogramderivative is used for detecting the difference in illumination, and henceforgery detection is accomplished. Prior to performing the forgery detectionprocess, some pre-processing techniques, including histogram equalization,histogram matching, high-pass filtering, homomorphic enhancement, andsingle image super-resolution, are introduced to reinforce the details andchanges between the original and embedded sections. The proposed approachfor copy-move forgery detection is performed with the Speeded Up Robustfeatures (SURf) algorithm, which extracts feature points and feature vectors. Searching for the copied partition is accomplished through matchingwith Euclidian distance and hierarchical clustering. In addition, some preprocessing methods are used with the SURf algorithm, such as histogramequalization and single-mage super-resolution. Simulation results proved thefeasibility and the robustness of the pre-processing step in homomorphicdetection and SURf detection algorithms for splicing and copy-move forgerydetection, respectively.

关键词： Image forgery splicing algorithm copy-move algorithm histogram matching homomorphic enhancement SISR SURf

Proposed Different Signal Processing Tools for Efficient Optical Wireless Communications

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Computers, Materials & Continua 2022年第5期71卷 3293-3318页

作者： Hend Ibrahim Abeer D.Algarni Mahmoud Abdalla walid El-Shafai fathi E.Abd El-Samie Naglaa f.Soliman Department of Electronics and Communications Engineering Faculty of EngineeringZagazig UniversityZagazig44519Egypt Department of Information Technology College of Computer and Information SciencesPrincess Nourah Bint Abdulrahman UniversityRiyadhSaudi Arabia Department of Electronics and Electrical Communications Engineering Faculty of Electronic EngineeringMenoufia UniversityMenoufia32952Egypt Security Engineering Lab Computer Science DepartmentPrince Sultan UniversityRiyadh 11586Saudi Arabia

Optical Wireless Communication(OWC)is a new trend in communication systems to achieve large bandwidth,high bit rate,high security,fast deployment,and low *** basic idea of the OWC is to transmit data on unguided media with *** system requires multi-carrier modulation such as Orthogonal frequency Division Multiplexing(OfDM).This paper studies optical OfDM performance based on Intensity Modulation with Direct Detection(IM/DD)*** system requires a non-negativity *** paper presents a framework for wireless optical OfDM system that comprises(IM/DD)with different forms,Direct Current biased Optical OfDM(DCO-OfDM),Asymmetrically Clipped Optical OfDM(ACO-OfDM),Asymmetrically DC-biased Optical OfDM(ADO-OfDM),and *** also considers channel coding as a tool for error control,channel equalization for reducing deterioration due to channel effects,and investigation of the turbulence *** evaluation results of the proposed framework reveal enhancement of *** performance of the IM/DD-OfDM system is investigated over different channel models such as AWGN,log-normal turbulence channel model,and ceiling bounce channel *** simulation results show that the BER performance of the IM/DD-OfDM communication system is enhanced while the fading strength is *** results reveal also that Hamming codes,BCH codes,and convolutional codes achieve better BER ***,two algorithms of channel estimation and equalization are considered and *** algorithms include the Least Squares(LS)and the Minimum Mean Square Error(MMSE).The simulation results show that the MMSE algorithm gives better BER performance than the LS algorithm.

关键词： Optical communication systems OWC IM/DD OfDM MMSE LS ADO-OfDM DCO-OfDM ACO-OfDM

Secure and Robust Optical Multi-Stage Medical Image Cryptosystem

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Computers, Materials & Continua 2022年第1期70卷 895-913页

作者： walid El-Shafai Moustafa H.Aly Abeer D.Algarni fathi E.Abd El-Samie Naglaa f.Soliman Department Electronics and Electrical Communications Faculty of Electronic EngineeringMenoufia UniversityMenouf32952Egypt Department of Electronics and Communications Engineering College of Engineering and TechnologyArab Academy for ScienceTechnology and Maritime TransportAlexandria1029Egypt Department of Information Technology College of Computer and Information SciencesPrincess Nourah Bint Abdulrahman UniversityRiyadh84428Saudi Arabia Department of Electronics and Communications Faculty of EngineeringZagazig UniversityZagazig44519Egypt

Due to the rapid growth of telemedicine and healthcare services,color medical image security applications have been expanded *** this paper,an asymmetric PTfrfT(Phase Truncated fractional fourier Transform)-based color medical image cryptosystem is *** different phases in the fractional fourier and output planes are provided as deciphering ***,the ciphering keys will not be employed for the deciphering ***,the introduced PTfrfT algorithm comprises asymmetric ciphering and deciphering processes in contrast to the traditional optical symmetric OSH(Optical Scanning Holography)and DRPE(Double Random Phase Encoding)*** of the principal impacts of the introduced asymmetric cryptosystem is that it eliminates the onedimensionality aspects of the related symmetric cryptosystems due to its remarkable feature of phase nonlinear truncation *** comparisons on various colormedical images are examined and analyzed to substantiate the cryptosystem *** achieved experimental outcomes ensure that the introduced cryptosystem is robust and *** has terrific cryptography performance compared to conventional cryptography algorithms,even in the presence of noise and severe channel attacks.

关键词： Optical encryption medical image security symmetric and asymmetric encryption OSH DRPE PTfrfT

DNA Binding and Antitumor Activity of a New fluores cent ProbeEu(Ⅲ)-Complex Containing 4-Methyl-Coumarin Moiety

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光谱学与光谱分析 2018年第11期38卷 3611-3621页

作者： Belal H M Hussein Mostafa A Gouda Omer Sakin Abdulla faluji mohamed Gomaa Hassan A Azab walid fathalla Sherin Arabi Sa wsan Mosa Chemistry Department Faculty of Science&ArtsAl UlaTaibah UniversityAl Madina Al MonawarahKSA Department of Chemistry Faculty of ScienceSuez Canal UniversityIsmailiaEgypt Chemistry Department Faculty of ScienceMansoura UniversityAl MansouEgypt Biotechnology Research Center Suez Canal Universitylsmailia 41522Egypt Medicinal Chemistry Department Faculty of PharmacySuez Canal Universitylsmailia 41522Egypt Department of Mathematical and Physical Sciences Faculty of EngineeringPort-Said UniversityPort-SaidEgypt Department of Mathematical and Physical Sciences Faculty of EngineeringSuez Canal UniversitylsmailiaEgypt Department of Chemistry Faculty of Educationel Arish UniversityEgypt

A new europium(Ⅲ)complex containing(4-Methyl-2-oxo-2 H-chromen-7-yloxy)-acetic acid moiety(CMMC)was synthesized,characterized,and confirmed as antitumor agent and fluorescent *** spectroscopic measurements of Eu(Ⅲ)in the presence of CMMC were obtained in different *** results show that the strongest Eu(Ⅲ)emission bands were monitored in iso-propyl alcohol while the weakest Eu(Ⅲ)emission band was observed in *** interaction of Eu(Ⅲ)-(CMMC)2 complex with DNA was monitored using absorption and emission *** fluorescence titration measurements,the binding constants of DNA with Eu(Ⅲ)-(CMMC)_2 complex were found to be 1.04×10~5 L·mol^(-1) in Tris-HCl and 1.17×10~7 L·mol^(-1) in DMSO-Tris-HCl buffer(9∶1 V/V).Hypochromism was observed from the absorption titration experiment which indicates the intercalation of Eu(Ⅲ)-complex between the base pair of *** result further confirmed by fluorescent Ethidium bromide displacement *** fluorescence calibration curve was used for the determination of DNA with LOD of 1.2 ng in DMSO-Tris-HCl buffer(9∶1 V/V)and 5 ng in Tris-HCl *** preliminary antitumor investigation shows promising cytotoxicity against MDA-MB-231,MCf-7(mammary cancer),and PC-3(prostate carcinoma)cell lines with IC50 values of 40.63,25.42 and 30.25μmol·L^(-1),respectively.

关键词： Europium (4-Methyl-2-oxo-2H-chromen-7-yloxy)-acetic acid DNA sensing Spectroscopic properties Antitumor activ ity

An Efficient GCD-Based Cancelable Biometric Algorithm for Single and Multiple Biometrics

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Computers, Materials & Continua 2021年第11期69卷 1571-1595页

作者： Naglaa f.Soliman Abeer D.Algarni walid El-Shafai fathi E.Abd El-Samie Ghada M.El Banby Department of Information Technology College of Computer and Information SciencesPrincess Nourah Bint Abdulrahman UniversityRiyadh84428Saudi Arabia Department of Electronics and Communications Faculty of EngineeringZagazig UniversityZagazig44519Egypt Department of Electronics and Electrical Communications Faculty of Electronic EngineeringMenoufia UniversityMenouf32952Egypt Department of Industrial Electronics and Control Engineering Faculty of Electronic EngineeringMenoufia UniversityMenouf32952Egypt

Cancelable biometrics are required in most remote access applications that need an authentication stage such as the cloud and Internet of Things(IoT)*** objective of using cancelable biometrics is to save the original ones from hacking attempts.A generalized algorithm to generate cancelable templates that is applicable on both single and multiple biometrics is proposed in this paper to be considered for cloud and IoT *** original biometric is blurred with two co-prime ***,it can be recovered as the Greatest Common Divisor(GCD)between its two blurred *** changes if induced in the biometric image prior to processing with co-prime operators prevents the recovery of the original biometric image through a GCD ***,the ability to change cancelable templates is guaranteed,since the owner of the biometric can pre-determine and manage the minimal change induced in the biometric ***,we test the utility of the proposed algorithm in the single-and multi-biometric *** multi-biometric scenario depends on compressing face,fingerprint,iris,and palm print images,simultaneously,to generate the cancelable *** metrics such as Equal Error Rate(EER)and Area and Receiver Operator Characteristic curve(AROC)are *** results on single-and multi-biometric scenarios show high AROC values up to 99.59%,and low EER values down to 0.04%.

关键词： Cloud IoT cancelable biometrics GCD single-and multi-biometrics security applications

COVID-19 Classification from X-Ray Images:An Approach to Implement federated Learning on Decentralized Dataset

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Computers, Materials & Continua 2023年第5期75卷 3883-3901页

作者： Ali Akbar Siddique S.M.Umar Talha M.Aamir Abeer D.Algarni Naglaa f.Soliman walid El-Shafai Department of Telecommunication Engineering Sir Syed University of Engineering&TechnologyKarachi75300Pakistan Department of Information Technology College of Computer and Information SciencesPrincess Nourah bint Abdulrahman UniversityP.O.Box 84428Riyadh11671Saudi Arabia Security Engineering Lab Computer Science DepartmentPrince Sultan UniversityRiyadh11586Saudi Arabia Department of Electronics and Electrical Communications Engineering Faculty of Electronic EngineeringMenoufia UniversityMenouf32952Egypt

The COVID-19 pandemic has devastated our daily lives,leaving horrific repercussions in its *** to its rapid spread,it was quite difficult for medical personnel to diagnose it in such a big *** who test positive for Covid-19 are diagnosed via a nasal PCR *** comparison,polymerase chain reaction(PCR)findings take a few hours to a few *** PCR test is expensive,although the government may bear expenses in certain ***,subsets of the population resist invasive testing like ***,chest X-rays or Computerized Vomography(CT)scans are preferred in most cases,and more importantly,they are non-invasive,inexpensive,and provide a faster response *** advances in Artificial Intelligence(AI),in combination with state-of-the-art methods,have allowed for the diagnosis of COVID-19 using chest *** article proposes a method for classifying COVID-19 as positive or negative on a decentralized dataset that is based on the federated learning *** order to build a progressive global COVID-19 classification model,two edge devices are employed to train the model on their respective localized dataset,and a 3-layered custom Convolutional Neural Network(CNN)model is used in the process of training the model,which can be deployed from the *** two edge devices then communicate their learned parameter and weight to the server,where it aggregates and updates the *** proposed model is trained using an image dataset that can be found on *** are more than 13,000 X-ray images in Kaggle Database collection,from that collection 9000 images of Normal and COVID-19 positive images are *** edge node possesses a different number of images;edge node 1 has 3200 images,while edge node 2 has *** is no association between the datasets of the various nodes that are included in the *** doing it in this manner,each of the nodes will have access to a separate image collection that has no correl

关键词： Artificial intelligence deep learning federated learning COVID-19 decentralized image dataset