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Journal of Groundwater Science and Engineering 2024年第1期12卷 16-33页

作者： masoud h hamed Rebwar N Dara Marios C Kirlas Department of Earth Sciences and Petroleum College of ScienceSalahaddin University-ErbilErbilIraq Department of Petroleum Engineering College of EngineeringKnowledge UniversityErbilIraq Department of Agriculture Faculty of AgricultureForestry and Natural EnvironmentAristotle University of Thessaloniki

Groundwater vulnerability assessment is a crucial step in the efficient management of groundwater resources,especially in areas with intensive anthropogenic activities and groundwater *** the present study,the DRASTIC method was applied using Geographic Information System(GIS)to delineate groundwater vulnerability zones in the Erbil Dumpsite area,Central Erbil Basin,North *** showed that the area was classified into four vulnerability classes:Very low(16.97%),low(27.67%),moderate(36.55%)and high(18.81%).The southern,south-eastern and northern parts of the study area exhibited the highest vulnerability potential,while the central-northern,northern and north-western regions displayed the lowest vulnerability ***,results of the single-parameter sensitivity analysis indicated that amongst the seven DRASTIC parameters,the unsaturated zone and the aquifer media were the most influencing *** conclustion,the correlation of 25 nitrate concentration values with the final vulnerability map,assessed using the Pearson correlation coefficient,yielded a satisfactory result of R=0.72.

关键词： DRASTIC Erbil Iraq Groundwater vulnerability assessment Nitrate Pollution Sensitivity analysis

Determination of Parameters Affecting the Estimation of Iceberg Draft

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China Ocean Engineering 2023年第1期37卷 62-72页

作者： hamed AZIMI masoud MAhDIANPARI hodjat ShIRI Civil Engineering Department Faculty of Engineering and Applied ScienceMemorial University of NewfoundlandA1B 3X5St.John’sNLCanada Department of Electrical and Computer Engineering Faculty of Engineering and Applied ScienceMemorial University of NewfoundlandA1B 3X5St.John’sNLCanada C-CORE A1B 3X5St.John’sNLCanada

Recent offshore oil and gas loading facilities developed in the Arctic area have led to a considerable awareness of the iceberg draft approximation, where deep keel icebergs may gouge the ocean floor, and these submarine infrastructures would be damaged in the shallower waters. Developing reliable solutions to estimate the iceberg draft requires a profound understanding of the problem’s dominant parameters. As such, the dimensionless groups of the parameters affecting the iceberg draft estimation were determined for the first time in the present study. Using the dimensionless groups recognized and the linear regression(LR) analysis, nine LR models(i.e., LR 1 to LR 9) were developed and then validated using a comprehensive dataset, which has been constructed in this study. A sensitivity analysis distinguished the premium LR models and important dimensionless groups. The best LR model, as a function of all dimensionless parameters, was able to estimate the iceberg draft with the highest level of precision and correlation along with the lowest degree of complexity. The ratio of iceberg length to iceberg height as the “iceberg length ratio” and the ratio of iceberg width to iceberg height as the “iceberg width ratio” was detected as the important dimensionless groups in the estimation of the iceberg draft. An uncertainty analysis demonstrated that the best LR model was biased towards underestimating the iceberg drafts. The premium LR model outperformed the previous empirical ***, a set of LR-based relationships were derived for estimating the iceberg drafts for practical engineering applications, e.g., the early stages of the iceberg management projects.

关键词： dimensional analysis iceberg draft subsea assets linear regression(LR) sensitivity analysis

Introducing a proper hydrogen liquefaction concept for using wasted heat of thermal power plants-case study: Parand gas power plant

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Chinese Journal of Chemical Engineering 2021年第12期34卷 187-196页

作者： hamed Rezaie Azizabadi masoud Ziabasharhagh Mostafa Mafi Faculty of Mechanical Engineering K.N.Toosi University of TechnologyTehranIran Department of Mechanical Engineering Imam Khomeini International UniversityQazvinIran

A hydrogen liquefaction concept with an innovative configuration and a capacity of 4 kg·s^(-1)(345.6 t·d^(-1))is *** concept involves an ammonia absorption refrigeration system for the pre-cooling of hydrogen and MR streams from 25℃ to-30℃.The ammonia absorption refrigeration system is fed by exhaust gases of the Pa rand gas power plant that are normally dissipated to the environment with a temperature of 546℃.The simulation is performed by Aspen hYSYS V9.0,using two separate equations of state for simulating hydrogen and MR streams to gain more accurate results especially for ortho-para *** show that conversion enthalpy estimated by Aspen hYSYS,fits very well to the experimental *** the important independent variables and composition of MRs are done using trial and error procedure,a functional and straightforward method for complicated *** minimum temperature limit in the cooling section is lowered,and an ortho-para converter is implemented in this *** proposed concept performs well from energy aspects and leads to COP and SEC equal to 0.271 and 4.54 kW·h·kg^(-1),*** main advantage of this study is in the low SEC,eliminating the losses of the distribution network,and improving the ability of the hydrogen liquefaction for energy storage in off-peak times.

关键词： hydrogen Liquefaction Absorption refrigeration Waste treatment Mixed-refrigerant Ortho-para conversion

Synergistic effect of Al and Gd on enhancement of mechanical properties of magnesium alloys

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Progress in Natural Science:Materials International 2017年第2期27卷 228-235页

作者： Bita Pourbahari masoud Emamy hamed Mirzadeh School of Metallurgy and Materials Engineering College of EngineeringUniversity of Tehran

The effect of Gd/Al ratio on the properties of as-cast Mg-Gd-Al-Zn alloys was investigated by changing the chemical composition from that of AZ61 to GZ61. At the ratio of 1, the Al2Gd phase becomes predominant and Mg17Al12is hardly seen in the microstructure. As a potent inoculant, the Al2Gd phase resulted in intense grain refinement and enhancement of strength, ductility and toughness. For instance, the tensile strength and elongation to failure of Mg-3Gd-3Al-1Zn alloy were enhanced by4% and 180% compared with those of AZ61 alloy, respectively. however, at high Gd/Al ratios, the Al2Gd phase was replaced by（Mg,Al）3Gd and Mg5 Gd phases and very large grain sizes were achieved, which led to poor tensile properties and the appearance of cleavage facets on the fracture surfaces. Therefore, it can be deduced that the presence of Gd and Al, in appropriate amounts to reach Gd/Al ratio of ~ 1, is required for the achievement of grain refinement, good ductility, high strength, and the appearance of ductile fracture surfaces in the Mg-Gd-Al-Zn ***, the Mg-Gd-Al-Zn alloys can be considered as a new class of structural magnesium alloy and it is superior to both AZ（Mg-Al-Zn） and GZ（Mg-Gd-Zn） series of alloys.

关键词： Magnesium alloys Rare earth elements Microstructure Mechanical properties

Continuous and Discrete Adjoint Approach Based on Lattice Boltzmann Method in Aerodynamic Optimization Part I:Mathematical Derivation of Adjoint Lattice Boltzmann Equations

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Advances in Applied Mathematics and Mechanics 2014年第5期6卷 570-589页

作者： Mohamad hamed hekmat masoud Mirzaei Center of Excellence for Design&Simulation of Space Systems K.N.Toosi University of TechnologyTehran891567Iran

The significance of flow optimization utilizing the lattice Boltzmann(LB)method becomes obvious regarding its advantages as a novel flow field solution method compared to the other conventional computational fluid dynamics *** unique characteristics of the LB method form the main idea of its application to optimization *** this research,for the first time,both continuous and discrete adjoint equations were extracted based on the LB method using a general procedure with low implementation *** proposed approach could be performed similarly for any optimization problem with the corresponding cost function and design variables ***,this approach was not limited to flow fields and could be employed for steady as well as unsteady ***,the continuous and discrete adjoint LB equations and the cost function gradient vector were derived mathematically in detail using the continuous and discrete LB equations in space and time,***,new adjoint concepts in lattice space were ***,the analytical evaluation of the adjoint distribution functions and the cost function gradients was carried out.

关键词： Aerodynamic optimization continuous and discrete adjoint approach lattice Boltzmann method

Exploring the mechanical properties of steel-and polypropylene-reinforced ultra-high-performance concrete through numerical analyses and experimental multi-target digital image correlation

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Frontiers of Structural and Civil Engineering 2023年第8期17卷 1228-1248页

作者： Behrooz DADMAND hamed SADAGhIAN Sahand KhALILZADEhTABRIZI masoud POURBABA Amir MIRMIRAN Department of Civil Engineering University of RaziKermanshah ***Iran Department of Civil Engineering University of TabrizTabriz ***Iran Ingram School of Engineering Texas State UniversitySan MarcosTX 78666USA University of Texas at Tyler TylerTX 75799USA

This study presents experimental and numerical investigations on the mechanical properties of ultrahigh-performance concrete(UhPC)reinforced with single and hybrid micro-and macro-steel and polypropylene *** this purpose,a series of cubic,cylindrical,dog-bone,and prismatic beam specimens(total fiber by volume=1%,and 2%)were tested under compressive,tensile,and flexural loadings.A method,namely multi-target digital image correlation(MT-DIC)was used to monitor the displacement and deflection *** obtained experimental data were subsequently used to discuss influential parameters,i.e.,flexural strength,tensile strength,size effect,*** analyses were also carried out using finite element software to account for the sensitivity of different ***,nonlinear regression analyses were conducted to obtain the flexural load-deflection *** results showed that the MT-DIC method was capable of estimating the tensile and flexural responses as well as the location of the crack with high *** addition,the regression analyses showed excellent consistency with the experimental results,with correlation coefficients close to ***,size-effect modeling revealed that modified Bazant theory yielded the best estimation of the size-effect phenomenon compared to other models.

关键词： UhPC MT-DIC flexural behavior tensile behavior steel fiber polypropylene fiber

Modal interactions in primary and subharmonic resonant dynamics of imperfect microplates with geometric nonlinearities

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Acta Mechanica Sinica 2016年第3期32卷 469-480页

作者： hamed Farokhi Mergen h.Ghayesh Department of Mechanical Engineering McGill University School of Mechanical Materials and MechatronicEngineering University of Wollongong

This paper analyses the modal interactions in the nonlinear, size-dependent dynamics of geometrically imperfect microplates. Based on the modified couple stress theory,the equations of motion for the in-plane and out-of-plane motions are obtained employing the von Kármán plate theory as well as Kirchhoff＇s hypotheses by means of the Lagrange equations. The equations of motions are solved using the pseudo-arclength continuation technique and direct timeintegration method. The system parameters are tuned to the values associated with modal interactions, and then nonlinear resonant responses and energy transfer are *** motion characteristics are shown in the form of frequency-response and force-response curves, time histories, phase-plane portraits, and fast Fourier transforms.

关键词： Modal interactions Microplate Sizedependent dynamics Modified couple stress theory Stability

Advantages of employing multilevel monitoring wells for design of tunnels subjected to multi-aquifer alluvial

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Journal of Mountain Science 2021年第1期18卷 219-232页

作者： Mohsen GOLIAN Ebrahim ShARIFI TEShNIZI hamed TAVASOLI ROSTAMI homayoon KATIBEh Mario PARISE masoud MAhDAD habib SAADAT Mehdi ABBASI Mahshid EBAD ARDESTANI Tehran Science and Research Branch Islamic Azad UniversityTehran ***Iran Department of Geology Faculty of SciencesFerdowsi UniversityMashhad 917751436Iran Mining and Metallurgical Engineering Department Amirkabir University of Technology(Tehran Polytechnic)Tehran ***Iran Earth and Environmental Sciences Department University Aldo MoroBari 70121Italy Iran University of Science and Technology Tehran ***Iran Shiraz University Shiraz ***Iran

For tunnels being excavated through multiple knowledge of the aquifers’hydraulic head becomes essential for determining groundwater inflow into the tunnel and analyzing its stability,specifically using multilevel monitoring *** the multi-aquifer alluvial section of the Glas tunnel(Iran),since the hydraulic head calculations were based on the data obtained from single-piezometer boreholes,the excavation risk was assessed to be at high level and the tunnel seemed to be unstable,thus an incorrect conclusion was derived from the misleading *** take cost mitigation measures into account,it was necessary to calculate the hydraulic head at tunnel level *** installing nested and clustered wells the mean hydraulic head was measured to be 70 m,significantly different from the 90 m previously determined by *** the updated value,the groundwater inflow and bulkhead load,formerly calculated as 0.65 m^(3)/s and 9.5 bars,were determined to be 0.49 m^(3)/s and 7.5 bars,respectively.

关键词： Nested wells Clustered wells hydraulic head Pumping test Mechanized tunneling Iran

Task Scheduling Optimization in Cloud Computing Based on Genetic Algorithms

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Computers, Materials & Continua 2021年第12期69卷 3289-3301页

作者： Ahmed Y.hamed Monagi h.Alkinani Faculty of Computers and Information Department of Computer ScienceSohag UniversitySohag82524Egypt Department of Computer Science and Artificial Intelligence College of Computer Science and EngineeringUniversity of JeddahJeddah21959Saudi Arabia

Task scheduling is the main problem in cloud computing that reduces system performance;it is an important way to arrange user needs and perform multiple *** computing is the most popular technology nowadays and has many research potential in various areas like resource allocation,task scheduling,security,privacy,*** improve system performance,an efficient task-scheduling algorithm is *** task-scheduling algorithms focus on task-resource requirements,CPU memory,execution time,and execution *** this paper,a task scheduling algorithm based on a Genetic Algorithm(GA)has been presented for assigning and executing different *** proposed algorithm aims to minimize both the completion time and execution cost of tasks and maximize resource *** evaluate our algorithm’s performance by applying it to two examples with a different number of tasks and *** first example contains ten tasks and four processors;the computation costs are generated *** last example has eight processors,and the number of tasks ranges from twenty to seventy;the computation cost of each task on different processors is generated *** achieved results show that the proposed approach significantly succeeded in finding the optimal solutions for the three objectives;completion time,execution cost,and resource utilization.

关键词： Cloud computing task scheduling genetic algorithm optimization algorithm

Investigating the Role of Bushehr Nuclear Power Plants(BNPPs)in Line with Achieving the Perspective of Sustainable Energy Development in Iran

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Journal of Thermal Science 2022年第5期31卷 1392-1406页

作者： NASOURI masoud DELGARM Navid Department of Environment Aras International CampusUniversity of TehranTehran***Iran Department of Mechanical Engineering Malek-Ashtar University of TechnologyIsfahan83145/115Iran

In line with achieving the outlook of Sustainable Energy Development(SED),Iran intends to increase the share of clean power to at least 8%of the country’s capacity by the end of *** research aims to investigate the role and share of Bushehr Nuclear Power Plants(BNPP-1,2,3)in achieving the SED perspective of Iran,which has never been examined so *** this connection,the comparative analyses of various power plants(PPs)of Iran including nuclear,fossil fuel,biomass,wind,solar thermal,photovoltaic,geothermal,and hydro PPs are carried out and *** main indicators of SED such as Levelized Cost of Electricity(LCOE)metric,grid-level system cost,investment cost,external cost,average CO_(2) equivalent emission,ecosystem impact,required land area,required water,preservation of natural resources,human health,created jobs,international cooperation,social acceptance and Corporate Social Responsibility(CSR),and energy-water hub are thoroughly *** statistical data used in the present study are extracted based on the authors’experiences gained during the construction,operation and maintenance(O&M)of BNPP-1,the energy-environment balance sheets of Iran,as well as the design documents of ***,the gathered data are evaluated using MatLab programing language and analyzed in terms of comparative *** evaluations of BNPP-1 performance within the framework of SED indicate that BNPP-1 has little effect on ecosystems and is among the lowest greenhouse gases emitters compared to other Iran’s PPs so that it annually prevent the release of 0.7 million tonnes of carbon,SO_(x),and NO_(x) compared to a gas-fired ***,the cost analysis shows that the external cost of BNPP-1 is nearly zero and the grid-level cost is approximately 3 USD/(MW·h)which is much lower than that for renewable *** per the LCOE metric and the cost of fuel supply,BNPP-1 is cost-competitive with other Iran’s *** nuclear fuel cost of BNPP-1 is nearly 49 million USD per

关键词： BNPP Sustainable Energy Development(SED) economic social environment