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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

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

CFD EVALUATION OF THE POTTERY WATER WALL IN A HOT ARID CLIMATE OF LUXOR,EGYPT

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Journal of Green Building 2014年第4期9卷 175-189页

作者： moustafa Anwar moustafa Srazali Aripin International Islamic University Malaysia Kulliyyah of Architecture and Environmental Design50728P.O.Box 10Kuala LumpurMalaysia 不详

This paper aims to evaluate the Pottery Water Wall in a hot arid climate using CFD *** Pottery Water Wall is a passive system and an upgrade to the Water *** Pottery Water Wall is a combination of a Water Wall and Porous Ceramic Pipes for evaporative ***,the study will evaluate the efficiency of the Pottery Water Wall in cooling and heating in the most extreme climatic conditions of winter and summer in Luxor,*** study will aid determining the ability of the Pottery Water Wall to cool and heat buildings and its ability to achieve thermal *** study found that the Pottery Water Wall’s cooling ability ranges between 4oC to 10oC,while its heating ability ranges between 4oC to *** Pottery Water Wall achieved thermal comfort for 62.5%of a day resembling extreme summer and achieved thermal comfort 62.5%of a day resembling extreme *** conclusion,the Pottery Water Wall can reduce cooling and heating demand by 88%at the extreme climatic conditions of Luxor,Egypt.

关键词： Passive design pottery water wall water wall porous ceramic evaporative cooling CFD

Calculation of ship motions in steep waves with restoring and Froude-Krylov forces on an adaptive panel mesh with Gauss and analytic integration methods

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Journal of Hydrodynamics 2024年第2期36卷 275-289页

作者： Malwin Wermbter moustafa Abdel-Maksoud Institute for Fluid Dynamics and Ship Theory Hamburg University of TechnologyHamburgGermany

The impulse response method is a frequently used method to calculate ship seakeeping *** this paper,the restoring and Froude-Krylov calculation is conducted with constant evaluation of panel pressures as well as Gauss quadrature and an analytical *** applied panel grid is coarsened by an adaptive algorithm which is based on a normal vector *** comparison of methods is based on grid convergence studies which are followed by a verification of forces with computational fluid dynamics(CFD)results on the fixed duisburg test case in *** with experimental results in head,oblique and following waves show that all integration methods are *** exact integration is numerically sensitive in some *** quadrature is highly accurate;however,the additional effort is not beneficial since the geometrical accuracy has-stronger influence on the force amplitudes than the integration *** grid coarsening reduces the simulation time and is accurate up to a level,where the panel length comes close the *** added resistance at the investigated Froude number of 0.05 shows higher uncertainty levels,this applies to the results of both the numerical methods and model tests.

关键词： Ship hydrodynamics seakeeping impulse response method added resistance wave loads

Advances on numerical and experimental investigation of ship roll damping

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Journal of Hydrodynamics 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

Treating wastewater under zero waste principle using wetland mesocosms

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Frontiers of Environmental Science & Engineering 2021年第4期15卷 155-168页

作者： Safaa M.Ezzat Mohammed T.moustafa Microbiology Deptartment Central Laboratory for Environmental Quality Monitoring(CLEQM)National Water Research Center(NWRC)CairoEgypt

The present investigation demonstrates the synergistic action of using a sedimentation unit together with Cyperus papyrus(L.)wetland enriched with zeolite mineral in one-year round experiment for treating *** system was designed to support a horizontal surface flow pattern and showed satisfactory removal efficiencies for both physicochemical and bacteriological contaminants within 3 days of residence *** removal efficiencies ranged between 76.3%and 98.8%for total suspended solids,turbidity,iron,biological oxygen demand,and *** bacterial indicators(total and fecal coliforms,as well as fecal streptococci)and the potential pathogens(Escherichia coli,Staphylococcus aureus,and Pseudomonas aeruginosa)showed removal efficiencies ranged between 96.9%and 99.8%.We expect the system to offer a smart management for every component according to zero waste *** treated effluent was reused to irrigate the landscape of pilot area,and the excess sludge was recycled as fertilizer and soil *** zeolite mineral did not require regeneration for almost 36 weeks of operation,and enhanced the density of shoots(14.11%)and the height of shoots(15.88%).The harvested plant biomass could be a profitable resource for potent antibacterial and antioxidant bioactive *** could certainly offset part of the operation and maintenance costs and optimize the system implementation *** the experiment was designed under local conditions,its results could provide insights to upgrade and optimize the performance of other analogous large-scale constructed wetlands.

关键词： Wastewater Dynamic roughing filter Cyperus papyrus(L.) Zeolite Zero waste