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Planning Target Volume Margin in Linac-Based Stereotactic Radiosurgery for Brain Metastases

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Journal of Cancer Therapy 2024年第7期15卷 265-272页

作者： hany S. Attallah Radwa M. hamed Khaled M. EL-Shahat Aliaa Mahmoud Mahmoud Abdallah Ibraheem haggag Emad moustafa Adel Yassin Department of Radiation Oncology International Medical Center (IMC) Cairo Egypt Department of Radiation Oncology Armed Forces Medical Collogue (AFCM) Cairo Egypt Department of Medical Physics Al Azhar University Cairo Egypt Department of Medical Physics International Medical Center (IMC) Cairo Egypt Department of Medical Physics Department of Clinical Oncology Faculty of Medicine Zagazig University Zagazig Egypt

Background: The treatment of brain metastases with radiotherapy has shifted to the use of Stereotactic Radio-surgery (SRS). The technical issue of expanding the treatment volume around the Gross Tumor Volume (GTV) is a current debate. Radiotherapy centers use variable GTV-PTV margins, ranging from one to 2 mm. Material and Methods: We performed a dosimetric comparison in plans of twenty patients using three margins: PTV zero, PTV1, and PTV2. We also developed imaginary Peel volumes. These volumes are described as follows: Peel1 = PTV1 − GTV, Peel2 = PTV2 − GTV. Results: Our results showed that the mean PTV volume differed significantly across the different margins (p = 0.000). The V12 of the brain significantly varied as a function of PTV margin (p = 0.000). The target coverage and plan quality indices were not significantly different. The Peel volume dosimetric analysis showed that the mean dose was significantly higher in the nearby normal brain tissue: Peel1 (p = 0.022) and Peel 2 (p = 0.013). Conclusion: According to our dosimetric analysis, expanding the GTV into a PTV by 1 mm margin is more convenient than 2 mm.

关键词： SRS Brain Metastases PTV

On Learning Adaptive Service Compositions

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Journal of Systems Science and Systems Engineering 2021年第4期30卷 465-481页

作者： Ahmed moustafa Department of Computer Science Nagoya Institute of TechnologyGokiso-choShowa-kuNagoyaAichi466-8555Japan Faculty of Informatics Zagazig UniversityZagazigEgypt

Service composition is an important and effective technique that enables atomic services to be combined together to forma more powerful service,i.e.,a composite *** the pervasiveness of the Internet and the proliferation of interconnected computing devices,it is essential that service composition embraces an adaptive service provisioning *** learning has emerged as a powerful tool to compose and adapt Web services in open and dynamic ***,the most common applications of reinforcement learning algorithms are relatively inefficient in their use of the interaction experience data,whichmay affect the stability of the learning process when deployed to cloud *** particular,they make just one learning update for each interaction *** paper introduces a novel approach that aims to achieve greater data efficiency by saving the experience data and using it in aggregate to make updates to the learned *** proposed approach devises an offline learning scheme for cloud service composition where the online learning task is transformed into a series of supervised learning tasks.A set of algorithms is proposed under this scheme in order to facilitate and empower efficient service composition in the cloud under various policies and different *** results of our experiments show the effectiveness of the proposed approach for composing and adapting cloud services,especially under dynamic environment settings,compared to their online learning counterparts.

关键词： Service composition reinforcement learning cloud services offline learning

Framework for COVID-19 Segmentation and Classification Based on Deep Learning of Computed Tomography Lung Images

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Journal of Electronic Science and Technology 2022年第3期20卷 246-256页

作者： Wessam M.Salama moustafa h.Aly the Department of Basic Science Faculty of EngineeringPharos UniversityAlexandria12455Egypt the Department of Electronics and Communications Engineering College of Engineering and TechnologyArab Academy for ScienceTechnology and Maritime TransportAlexandria1029Egypt

Corona Virus Disease 2019(COVID-19) has affected millions of people worldwide and caused more than6.3 million deaths(World health Organization, June 2022). Increased attempts have been made to develop deep learning methods to diagnose COVID-19 based on computed tomography(CT) lung images. It is a challenge to reproduce and obtain the CT lung data, because it is not publicly available. This paper introduces a new generalized framework to segment and classify CT images and determine whether a patient is tested positive or negative for COVID-19 based on lung CT images. In this work, many different strategies are explored for the classification ***50 and VGG16 models are applied to classify CT lung images into COVID-19 positive or negative. Also,VGG16 and ReNet50 combined with U-Net, which is one of the most used architectures in deep learning for image segmentation, are employed to segment CT lung images before the classifying process to increase system performance. Moreover, the image size dependent normalization technique(ISDNT) and Wiener filter are utilized as the preprocessing techniques to enhance images and noise suppression. Additionally, transfer learning and data augmentation techniques are performed to solve the problem of COVID-19 CT lung images deficiency, therefore the over-fitting of deep models can be avoided. The proposed frameworks, which comprised of end-to-end, VGG16,ResNet50, and U-Net with VGG16 or ResNet50, are applied on the dataset that is sourced from COVID-19 lung CT images in Kaggle. The classification results show that using the preprocessed CT lung images as the input for U-Net hybrid with ResNet50 achieves the best performance. The proposed classification model achieves the 98.98%accuracy(ACC), 98.87% area under the ROC curve(AUC), 98.89% sensitivity(Se), 97.99 % precision(Pr), 97.88%F-score, and 1.8974-seconds computational time.

关键词： Augmentation classification computed tomography(CT) Corona Virus Disease 2019(COVID-19) deep learning ResNet50 segmentation U-Net VGG16

Genesis and Tectonic Implications of the Kabr El-Bonaya Ultramafic Rocks,Sinai Peninsula,Egypt:Constraints from Mineralogical and Geochemical Characteristics

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Acta Geologica Sinica(English Edition) 2021年第2期95卷 393-418页

作者： moustafa Mohammed MOGAhED Geology Department Benha University-EgyptBenhaEgypt

The Kabr El-Bonaya mafic–ultramafic intrusion is exposed along the southeastern border of the Sinai Peninsula and the northernmost segment of the Arabian-Nubian Shield(ANS).It occurs as an elliptical intrusive body that is located along the major NE–SW trending fracture zones that prevail in the Kid metamorphic *** ultramafic rocks in the complex comprise ultramafic cumulates of peridotites(dunite,harzburgite and wehrlite)and *** rocks are generally unmetamorphosed and have intrusive contacts with the country *** chemistry and whole-rock chemical compositions of these ultramafic rocks are mostly consistent with those of residual mantle peridotites from refractory suprasubduction tectonic *** on the variations of the major elements,the studied ultramafic rocks are consistent with those of a supra-subduction zone mantle,as it seems to have melted at 1–2 GPa and 1300–1450℃.Linear variations of Al2O3,Ca O,V and Ni with Mg O,coupled with incompatible and rare-earth-element depletion and mineral compositions,suggest prior events of partial melting in both wehrlites and *** LREE enrichment in the harzburgite,as well as the development of Cr-rich spinel,is consistent with a history of melt–peridotite *** calculated(Sm/Yb)N variations for the studied peridotites indicate a general increase in the addition of fluids with an increasing degree of melting from the wehrlite(~13–15 wt%of fluid)in the source,after initial spinel peridotite melting to the harzburgite(~20–25 wt%of fluid)in the same source,which is contrary to normal abyssal *** estimated equilibration temperature ranges from 1214 to 1321℃for the studied wehrlites and from 1297 to 1374℃for *** Mg-rich nature of the analysed olivines from the studied ultramafic rocks(Fo=81.41 to 91.77)reflect their primary composition and are similar to olivines in Alaskan-type ultramafic *** Fo content of the analyzed olivines decrease sli

关键词： cumulate ultramafic rocks Alaskan-type rocks partial melting hydrous melting conditions supra-subduction zone Kabr El-Bonaya South Sinai Arabian-Nubian Shield

Use of probabilistic and deterministic measures to identify unfavorable earthquake records

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第5期10卷 619-634页

作者： Abbas moustafa Izuru TAKEWAKI Department of Urban and Environmental Engineering Graduate School of Engineering Kyoto UniversityNishikyo-ku 615-8540 Japan Department of Civil Engineering School of Engineering Minia UniversityMinia 61111 Egypt

This study introduces measures to identify resonant (concentration of energy in a single or a few frequencies) or unfavorable earthquake ground motions. Probabilistic measures based on the entropy rate and the geometric properties of the power spectral density function (PSDF) of the ground acceleration are developed first. Subsequently, deterministic measures for the frequency content of the ground acceleration are also developed. These measures are then used for identifying resonance and criticality in stochastic earthquake models and 110 acceleration records measured at rock, stiff, medium and soft soil sites. The unfavorable earthquake record for a given structure is defined as the record having a narrow frequency content and dominant frequency close to the structure fundamental natural frequency. Accordingly, the measures developed in this study may provide a basis for selecting records that are capable of producing the highest structural response. Numerical verifications are provided on damage caused to structures by identified resonant records.

关键词： Entropy rate Dispersion index Power spectral density function (PSDF) Frequency content Unfavorable groundmotion Resonant acceleration Critical accelerogram Energy Damage index

Advances on numerical and experimental investigation of ship roll damping

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水动力学研究与进展B辑:英文版 2023年第3期35卷 431-448页

作者： Patrick Sumislawski moustafa Abdel-Maksoud Institute for Fluid Dynamics and Ship Theory Hamburg University of Technology (TUHH) Hamburg Germany

This paper presents recent developments towards efficient and reliable methods for roll damping estimation based on numerical simulations as well as model tests using the harmonic excited roll motion(hERM)technique.A newly designed automatic roll damping estimation procedure shows the advantage of a just-in-time post processing of experimental measurement ***-time analysis of the measured roll damping values permits a considerable shortening of the test ***,a large number of investigations can be carried out with relatively manageable effort in order to determine the roll damping behavior of different keel configurations or at operating conditions,e.g.,different sized keels or Froude *** addition,hERM measurement method is applied to investigate the memory *** this purpose,different excitation schemes are introduced and the results are ***,a study of the scale effect on the roll damping properties is conducted,in which experimental and numerical investigations are performed for two scales of a ship ***,a method is developed that significantly reduces the effort of Reynolds average Navier-Stokes(RANS)-based simulations of roll *** reduction of simulation time is achieved by introducing an artificial *** obtained results show that the developed method is very well applicable for numerical as well as in experimental *** the model tests using hERM technique,the model is free and the rudder is used to keep the straight-ahead *** analysis of the numerical and experimental results shows that the influence of the rudder induced force and moment during hERM tests is not negligible and the contribution of the rudder must be taken into account by estimating the roll ***,a new concept is developed to investigate the parametric roll behavior of ships,which allows neglecting the consideration of the complex modelling of free surface waves in the *** the RAN

关键词： Roll damping harmonic excited roll motion rudder hERM experimental fluid dynamics(EFD) CFD

houda Mohamed Mahmoud moustafa Abdalla Department of Mathematics

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Houda Mohamed Mahmoud Moustafa Abdalla Department of Mathema...

作者： houda Mohamed Mahmoud moustafa AbdcJla 华中师范大学

学位级别：硕士

In this thesis, we consider the solutions for the matrix equation AX— XA=A with A a given complex square matrix and X unknown. We prove that this equation has a solution if and only if A is nilpotent. Also, when A is... 详细信息

关键词： nilpotent eigenvalue integer 学位论文 Jordan algebra 论文注释 matrices 授权书 blocks

Evaluation of the microstructure,thermal and mechanical properties of Cu/SiC nanocomposites fabricated by mechanical alloying

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International Journal of Minerals,Metallurgy and Materials 2021年第3期28卷 475-486页

作者： Essam B.moustafa Mohammed A.Taha Mechanical Engineering Departments Faculty of EngineeringKing Abdulaziz UniversityJeddah 21589Saudi Arabia Solid State Physics Department National Research CentreEl Buhouth St.Dokki12622 GizaEgypt

Nano-sized silicon carbide(SiC:0wt%,1wt%,2wt%,4wt%,and 8wt%)reinforced copper(Cu)matrix nanocomposites were manufactured,pressed,and sintered at 775 and 875℃in an argon atmosphere.X-ray diffraction(XRD)and scanning electron microscopy were performed to characterize the microstructural *** density,thermal expansion,mechanical,and electrical properties were *** analyses showed that with increasing SiC content,the microstrain and dislocation density increased,while the crystal size *** coefficient of thermal expansion(CTE)of the nanocomposites was less than that of the Cu *** improvement in the CTE with increasing sintering temperature may be because of densification of the ***,the mechanical properties of these nanocomposites showed noticeable enhancements with the addition of SiC and sintering temperatures,where the microhardness and apparent strengthening efficiency of nanocomposites containing 8wt%SiC and sintered at 875℃were 958.7 MPa and 1.07 vol%^(−1),*** electrical conductivity of the sample slightly decreased with additional SiC and increased with sintering *** prepared Cu/SiC nanocomposites possessed good electrical conductivity,high thermal stability,and excellent mechanical properties.

关键词： copper matrix nanocomposites silicon carbide coefficient of thermal expansion elastic moduli electrical conductivity mechanical alloying

hybrid Single Image Super-Resolution Algorithm for Medical Images

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Computers, Materials & Continua 2022年第9期72卷 4879-4896页

作者： Walid El-Shafai Ehab Mahmoud Mohamed Medien Zeghid Anas MAli moustafa h.Aly Department of Electronics and Electrical Communications Engineering Faculty of Electronic EngineeringMenoufia UniversityMenouf32952Egypt Security Engineering Lab Computer Science DepartmentPrince Sultan UniversityRiyadh11586Saudi Arabia Electrical Engineering Department College of EngineeringPrince Sattam Bin Abdulaziz UniversityWadi Addwasir11991Saudi Arabia Electrical Engineering Department Aswan UniversityAswan81542Egypt Electronics and Micro-Electronics Laboratory(E.μ.E.L) Faculty of SciencesUniversity of MonastirMonastir5000Tunisia Alexandria higher Institute of Engineering&Technology(AIET) AlexandriaEgypt Electronics and Communications Engineering Department College of Engineering and TechnologyArab Academy for ScienceTechnology and Maritime TransportAlexandria1029Egypt

high-quality medical microscopic images used for diseases detection are expensive and difficult to ***,low-resolution images are favorable due to their low storage space and ease of sharing,where the images can be enlarged when needed using Super-Resolution(SR)***,it is important to maintain the shape and size of the medical images while enlarging *** of the problems facing SR is that the performance of medical image diagnosis is very poor due to the deterioration of the reconstructed image ***,this paper suggests a multi-SR and classification framework based on Generative Adversarial Network(GAN)to generate high-resolution images with higher quality and finer details to reduce *** proposed framework comprises five GAN models:Enhanced SR Generative Adversarial Networks(ESRGAN),Enhanced deep SR GAN(EDSRGAN),Sub-Pixel-GAN,SRGAN,and Efficient Wider Activation-B GAN(WDSR-b-GAN).To train the proposed models,we have employed images from the famous Breakhis dataset and enlarged them by 4×and 16×upscale factors with the ground truth of the size of 256×256×***,several evaluation metrics like Peak Signal-to-Noise Ratio(PSNR),Mean Squared Error(MSE),Structural Similarity Index(SSIM),Multiscale Structural Similarity Index(MS-SSIM),and histogram are applied to make comprehensive and objective comparisons to determine the best methods in terms of efficiency,training time,and storage *** obtained results reveal the superiority of the proposed models over traditional and benchmark models in terms of color and texture restoration and detection by achieving an accuracy of 99.7433%.

关键词： GAN medical images SSIM MS-SSIM PSNR SISR