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Spatiotemporal landscape pattern changes and their effects on land surface temperature in greenbelt with semi-arid climate:A case study of the Erbil City,Iraq

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Journal of Arid Land 2024年第9期16卷 1214-1231页

作者： Suzan ISMAIL hamid MALIKI Department of Architecture College of EngineeringSalahaddin UniversityErbil 44002Iraq

Urban expansion of cities has caused changes in land use and land cover(LULC)in addition to transformations in the spatial characteristics of landscape *** alterations have generated heat islands and rise of land surface temperature(LST),which consequently have caused a variety of environmental issues and threated the sustainable development of urban *** are employed as an urban planning containment policy to regulate urban expansion,safeguard natural open spaces,and serve adaptation and mitigation *** they are regarded as a powerful measure for enhancing urban environmental *** the fact that,the relation between landscape structure change and variation of LST has been examined thoroughly in many studies,but there is a limitation concerning this relation in semi-arid climate and in greenbelts as well,with the lacking of comprehensive research combing both ***,this study investigated the spatiotemporal changes of landscape pattern of LULC and their relationship with variation of LST within an inner greenbelt in the semi-arid Erbil City of northern *** study utilized remote sensing data to retrieve LST,classified LULC,and calculated landscape metrics for analyzing spatial changes during the study *** results indicated that both composition and configuration of LULC had an impact on the variation of LST in the study *** Pearson's correlation showed the significant effect of Vegetation 1 type(VH),cultivated land(CU),and bare soil(BS)on LST,as increase of LST was related to the decrease of VH and the increases of CU and BS,while,neither Vegetation 2 type(VL)nor built-up(BU)had any ***,the spatial distribution of LULC also exhibited significant effects on LST,as LST was strongly correlated with landscape indices for VH,CU,and ***,for BU,only aggregation index metric affected LST,while none of VL metrics had a *** study provides insights for landscape pla

关键词： land use and land cover change landscape pattern land surface temperature greenbelt remote sensing

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Velocity gradient elasticity for nonlinear vibration of carbon nanotube resonators

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Frontiers of Structural and Civil Engineering 2020年第6期14卷 1520-1530页

作者： hamid MSEDIGHI Hassen MOUAKAD Mechanical Engineering Deparment Faculty of Engineering Shahid Chamran University of AhvazAhvaz ***Iran Driling Center of Exellence and Research Center Shahid Chamran University of AhvazAhvaz ***Iran Mechanical and Industrial Engineering Department Collge of EngineeringSultan Qaboos UniversitMuscalOMAN

In this study,for the first time,we investigate the nonlocality superimposed to the size effects on the nonlinear dynamics of an electrically actuated single-walled carbon-nanotube-based *** undertake two models to capture the nanostructure nonlocal size effects:the strain and the velocity gradient *** use a reduced-order model based on the differential quadrature method(DQM)to discretize the goverming nonlinear equation of motion and acquire a discretized-parameter nonlinear model of the *** structural nonlinear behavior of the system assuming both strain and velocity gradient theories is investigated using the discretized *** results suggest that nonlocal and size effects should not be neglected because they improve the prediction of corresponding dynamic amplitudes and,most importantly,the critical resonant frequencies of such *** these effects may impose a considerable source of error,which can be amended using more accurate modeling techniques.

关键词： velocity gradient elasticity theory nanotube resonators differential-quadrature method nonlinear vibration

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Preparation of La-Mo-V mixed-oxide systems and their application in the direct synthesis of acetic acid

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Journal of Natural Gas Chemistry 2008年第3期17卷 213-224页

作者： hamid Reza Arandiyan Matin Parvari Chemical Engineering Department Iran University of Science and Technology

In this study, mixed metal oxides developed with a perovskite-type structure that show great potential for use in catalysis. Perovskite oxide catalysts with the composition LaMoxV1-xOn （x = 0.1, 0.3, 0.5, 0.7, and 0.9） have been synthesized by the sol-gel method and then used in the ethane dry reforming reaction for the direct synthesis of acetic acid. The influence of the nature of the metallic source （metal, nitrate, acetylacetonate, and ammonium） on gel formation has been studied by Fourier-transform infrared spectroscopy （FT-IR） and thermogravimetric analysis （TGA-DTA）. After calcination, the obtained perovskites were characterized by X-ray diffraction （XRD） and energy-dispersive X-ray spectrometry （EDS） coupled with scanning electron microscopy （SEM）. The catalysts were then subjected to thermo-programmed reduction （TPR）. The surface area （BET） was found to increase from 2.6 m^2/g （x = 0.1） to 5.1 m2/g （x = 1.0） with increasing molybdenum content following calcinations at 750 °C, and pure LaMoxV1-xOn perovskite was obtained with good homogeneity. The catalysts have been characterized by XRD, SEM, EDS, and carbon analysis （CA）. The results indicate that through this synthesis it is possible to obtain highly crystalline, homogeneous and pure solids, with well-defined structures. The direct synthesis of acetic acid from ethane over the perovskite catalysts was studied at temperatures between 450 and 850 °C and elevated pressures between 1 and 8 bar. It was found that the yield of acetic acid and the selectivity of its formation could be increased by incorporating more molybdenum into the perovskite structure. The experimental studies have shown that the calcination temperature and the molybdenum content have a significant influence on the catalytic activity. Amongst the catalysts tested, LaMo0.7V0.3O4.2 exhibited the best activity and stability.

关键词： acetic acid catalyst perovskite activity LaMoxV1-xOn

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Numerical and experimental study of an innovative pipeline design in a granular pneumatic-conveying system

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Particuology 2018年第3期16卷 196-203页

作者： Hasan Ghafori hamid Reza Ebrahimi Department of Mechanical Engineering MaJlesi Branch Islamic Azad University lsfilhan Iran Department of Chemical Engineering Majlesi Branch Islamic Azad University lsfahan Iran

During gas-solid mixture conveying in a dense phase, material is conveyed in dunes on the bottom of the pipeline, or as a pulsating moving bed. This phenomenon increases the pressure drop and power consumption. We introduce a new technique to reduce the pressure drop, which is termed the perforated double tube. To validate this new model, the gas-solid flow pattern and pressure drop were studied numerically and experimentally. The power consumption was also studied experimentally. Numerical studies were performed by the Eulerian-Lagrangian approach to predict gas and particle movement in the pipeline, Comparisons between the numerical predictions and the experimental results for the gas-solid flow patterns and pressure drop show good agreement.

关键词： Computational fluid dynamics Power consumption Perforated double tube Pneumatic conveying

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Static and Dynamic Pull-In Instability of Nano-Beams Resting on Elastic Foundation Based on the Nonlocal Elasticity Theory

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Chinese Journal of Mechanical Engineering 2017年第2期30卷 385-397页

作者： hamid M Sedighi ASHKAN Sheikhanzadeh Mechanical Engineering Department Faculty of EngineeringShahid Chamran University of Ahvaz Departmentof Mechanical Engineering Najafabad BranchIslamic Azad Univesity

This paper provides the static and dynamic pullin behavior of nano-beams resting on the elastic foundation based on the nonlocal theory which is able to capture the size effects for structures in micron and sub-micron scales. For this purpose, the governing equation of motion and the boundary conditions are driven using a variational approach. This formulation includes the influences of fringing field and intermolecular forces such as Casimir and van der Waals forces. The differential quadrature （DQ） method is employed as a high-order approximation to discretize the governing nonlinear differential equation, yielding more accurate results with a Considerably smaller number of grid points. In addition, a powerful analytical method called parameter expansion method （PEM） is utilized to compute the dynamic solution and frequency-amplitude relationship. It is illustrated that the first two terms in series expansions are sufficient to produce an acceptable solution of the mentioned structure. Finally, the effects of basic parameters on static and dynamic pull-in insta- bility and natural frequency are studied.

关键词： Static and dynamic pull·in voltages Size dependent Nonlocal theory Euler·Bernoulli beam model Differential quadrature method Parameter Expansion method

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Analytical modeling of static behavior of electrostatically actuatednano/micromirrors considering van der Waals forces

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Acta Mechanica Sinica 2012年第3期28卷 729-736页

作者： hamid Moeenfard Mohammad Taghi Ahmadian School of Mechanical Engineering Sharif University of Technology Center of Excellence in Design Robotics and AutomationSchool of Mechanical EngineeringSharif University of Technology

In this paper, the effect of van der Waals （vdW） force on the pull-in behavior of electrostatically actuated nano/micromirrors is investigated. First, the minimum po- tential energy principle is utilized to find the equation gov- erning the static behavior of nano/micromirror under electro- static and vdW forces. Then, the stability of static equilib- rium points is analyzed using the energy method. It is found that when there exist two equilibrium points, the smaller one is stable and the larger one is unstable. The effects of dif- ferent design parameters on the mirror＇s pull-in angle and pull-in voltage are studied and it is found that vdW force can considerably reduce the stability limit of the mirror. At the end, the nonlinear equilibrium equation is solved numer- ically and analytically using homotopy perturbation method （HPM）. It is observed that a sixth order perturbation approx- imation can precisely model the mirror＇s behavior. The re- suits of this paper can be used for stable operation design and safe fabrication of torsional nano/micro actuators.

关键词： Nano/micromirror Electrostatic actuation vdW force Pull-in. Homotopy perturbation method (HPM)

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Effect of seismic wave propagation in massed medium on rate-dependent anisotropic damage growth in concrete gravity dams

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Frontiers of Structural and Civil Engineering 2021年第2期15卷 346-363页

作者： Alireza DANESHYAR hamid MOHAMMADNEZHAD Mohsen GHAEMIAN Civil Engineering Department Sharif University of TechnologyTehran11155-9313Iran Faculty of Civil Water and Environmental EngineeringShahid Beheshti UniversityTehran11155-9313Iran

Seismic modeling of massive structures requires special caution,as wave propagation effects significantly affect the *** becomes more crucial when the path-dependent behavior of the material is *** coexistence of these conditions renders numerical earthquake analysis of concrete dams ***,a finite element model for a comprehensive nonlinear seismic simulation of concrete gravity dams,including realistic soil-structure interactions,is introduced.A semi-infinite medium is formulated based on the domain reduction method in conjunction with standard viscous *** representation of radiation damping in a half-space medium and wave propagation effects in a massed foundation are verified using an analytical solution of vertically propagating shear waves in a viscoelastic half-space domain.A rigorous nonlinear finite element model requires a precise description of the material ***,a microplane-based anisotropic damage-plastic model of concrete is formulated to reproduce irreversible deformations and tensorial degeneration of concrete in a coupled and rate-dependent ***,the Koyna concrete gravity dam is analyzed based on different assumptions of foundation,concrete response,and reservoir *** between responses obtained based on conventional assumptions with the results of the presented comprehensive model indicates the significance of considering radiation damping and employing a rigorous constitutive material model,which is pursued for the presented model.

关键词： soil-structure interaction massed foundation radiation damping anisotropic damage

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Generating one-,two-,three-and four-scroll attractors from a novel four-dimensional smooth autonomous chaotic system

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Chinese Physics B 2010年第6期19卷 106-114页

作者： Sara Dadras hamid Reza Momeni Automation and Instruments Lab Electrical Engineering DepartmentTarbiat Modares UniversityP.O.Box 14115-143TehranIran

A new four-dimensional quadratic smooth autonomous chaotic system is presented in this paper, which can exhibit periodic orbit and chaos under the conditions on the system parameters. Importantly, the system can generate one-, two-, three- and four-scroll chaotic attractors with appropriate choices of parameters. Interestingly, all the attractors are generated only by changing a single parameter. The dynamic analysis approach in the paper involves time series, phase portraits, Poincare maps, a bifurcation diagram, and Lyapunov exponents, to investigate some basic dynamical behaviours of the proposed four-dimensional system.

关键词： new smooth autonomous four-dimensional chaotic system multi-scroll chaotic attractor Poincare mapping bifurcation Lyapunov exponent

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Transferring information through a mixed-five-spin chain channel

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Chinese Physics B 2016年第8期25卷 53-58页

作者： hamid Arian Zad Hossein Movahhedian Department of Physics Shahrood University of Technology

We initially introduce one-dimensional mixed-five-spin chain with Ising-XY model which includes mixture of spins-1/2 and spins-1. Here, it is considered that nearest spins（1, 1/2） have Ising-type interaction and nearest spins（1/2, 1/2）have both XY-type and Dzyaloshinskii–Moriya（DM） interactions together. Nearest spins（1, 1） have X X Heisenberg interaction. This system is in the vicinity of an external homogeneous magnetic field B in thermal equilibrium state. We promote the quantum information transmitting protocol verified for a normal spin chain with simple model（refer to Rossini D, Giovannetti V and Fazio R 2007 Int. J. Quantum Infor. 5 439）（widely in reference： Giovannetti V and Fazio R 2005 Phys. Rev. A 71 032314） by means of considering the suggested mixed-five-spin chain as a quantum communication channel for transmitting both qubits and qutrits ideally. Hence, we investigate some useful quantities such as quantum capacity and quantum information transmission rate for the system. Finally, we conclude that, when the DM interaction between spins（1/2, 1/2） increases the system is a more ideal channel for transmitting information.

关键词： Dzyaloshinskii-Moriya interaction XX Heisenberg interaction communication channel transmission rate

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Preserving Privacy of Software-Defined Networking Policies by Secure Multi-Party Computation

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Journal of Computer Science & Technology 2020年第4期35卷 863-874页

作者： Maryam Zarezadeh hamid Mala Homa Khajeh Faculty of Computer Engineering University of IsfahanIsfahan ***Iran Independent Researcher Isfahan ***Iran

In software-defined networking(SDN),controllers are sinks of information such as network topology collected from *** often like to protect their internal network topology and keep their network policies *** borrow techniques from secure multi-party computation(SMC)to preserve the privacy of policies of SDN controllers about status of *** the other hand,the number of controllers is one of the most important concerns in scalability of SMC application in *** address this issue,we formulate an optimization problem to minimize the number of SDN controllers while considering their reliability in SMC *** use Non-Dominated Sorting Genetic Algorithm II(NSGA-II)to determine the optimal number of controllers,and simulate SMC for typical SDNs with this number of *** results show that applying the SMC technique to preserve the privacy of organization policies causes only a little delay in SDNs,which is completely justifiable by the privacy obtained.

关键词： software-defined networking (SDN) privacy secure multi-party computation (SMC) structure function multi-objective optimization

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