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Chinese Journal of Chemical Engineering 2019年第5期27卷 1021-1029页

作者： mohammad Reza Aghajanzadeh mohammad Sharifi Department of Petroleum Engineering Amirkabir University of Technology

In this study, the performance of stable nanofluid containing SiO2 nanoparticles dispersed and stabilized in high salinity brine for asphaltene inhibition in dynamic condition is evaluated. In the first stage of this work, the stability of silica nanoparticles in different range of water salinity(0–100000 mg·L-1) is investigated. Next, stable nanofluid containing highest salinity is selected as asphaltene inhibitor agent to inject into the damaged core sample. The estimated values of oil recovery for base case, after damage process and after inhibition of asphaltene precipitation using nanofluid are 51.6%, 36.1% and 46.7%, respectively. The results showed the reduction in core damage after using nanofluid. In addition, the relative permeability curves are plotted for the base case, after damage process and also after inhibition of asphaltene precipitation using nanofluid. Comparison of relative permeability curves shows, relative permeability of oil phase decreased after damage process as compared with the base case. But after using nanofluid the oil relative permeability curve has shifted to the right and effective permeability of oil phase has been improved.

关键词： Formation damage Enhanced oil recovery Salinity Asphaltene Core flooding Nano particles

Nonlinear analysis of cable structures using the dynamic relaxation method

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Frontiers of Structural and Civil Engineering 2021年第1期15卷 253-274页

作者： mohammad REZAIEE-PAJAND mohammad mohammadI-KHATAMI Department of Civil Engineering Ferdowsi University of MashhadMashhad ***Iran

The analysis of cable structures is one of the most challenging problems for civil and mechanical *** they have highly nonlinear behavior,it is difficult to find solutions to these *** far,different assumptions and methods have been proposed to solve such *** dynamic relaxation method(DRM)is an explicit procedure for analyzing these types of *** utilize this scheme,investigators have suggested various stiffness matrices for a cable *** this study,the efficiency and suitability of six well-known proposed matrices are assessed using the *** achieve this goal,16 numerical examples and two criteria,namely,the number of iterations and the analysis time,are *** on a comprehensive comparison,the methods are ranked according to the two *** numerical findings clearly reveal the best ***,a variety of benchmark problems are suggested by the authors for future studies of cable structures.

关键词： nonlinear analysis cable structure stiffness matrix dynamic relaxation method

DEM Numerical Simulation of Abrasive Wear Characteristics of a Bioinspired Ridged Surface

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Journal of Bionic Engineering 2010年第2期7卷 175-181页

作者： mohammad Almagzoub mohammad Carlo Menon Key Laboratory of Bionic Engineering Jilin University College of Biological and Agricultural Engineering Jilin University MENRVA Group Simon Fraser University

This paper presents numerical investigations into a ridged surface whose design is inspired by the geometry of a Farrer’*** objective of the performed research is to assess if the proposed Bioinspired Ridged Surface (BRS) can potentiallyimprove wear resistance of soil-engaging components used in agricultural machinery and to validate numerical simulationsperformed using software based on the Discrete Element Method (DEM).The wear performance of the BRS is experimentallydetermined and also compared with a conventional flat *** size of soil particles and relative velocities between theabrasive sand and the testing surfaces are *** results show that the numerical simulations are in agreement withthe experimental results and support the hypothesis that abrasive wear is greatly reduced by substituting a conventional flatsurface with the BRS.

关键词： bioinspired ridged surface abrasive wear numerical simulation Discrete Element Method (DEM)

Impact of demand growth on the capacity of long-duration energy storage under deep decarbonization

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Clean Energy 2024年第4期8卷 237-247页

作者： Sara ashfaq Ilyass El Myasse Daming Zhang Ahmed S.Musleh Carnegie Institution Stanford UniversityStanfordCAUSA Electric Power Research Institute(EPRI) Palo AltoCAUSA EEIS Laboratory ENSET MohammediaHassan II UniversityCasablancaMorocco School of Electrical Engineering and Telecommunications University of New South WalesSydneyAustralia

The weather-dependent uncertainty of wind and solar power generation presents a challenge to the balancing of power generation and demand in highly renewable electricity *** energy storage can provide flexibility to firm up the variability of renewables and to respond to the increased load demand under decarbonization *** paper explores how the battery energy storage capacity requirement for compressed-air energy storage(CAES)will grow as the load demand *** we used an idealized lowest-cost optimization model to study the response of highly renewable electricity systems to the increasing load demand of California under deep *** show that providing bulk CAES to the zero-emission power system offers substantial benefits,but it cannot fully compensate for the 100%variability of highly renewable power *** capacity requirement of CAES increases by≤33.3%with a 1.5 times increase in the load demand and by≤50%with a two-times increase in the load *** this analysis,a zero-emission electricity system operating at current costs becomes more cost-effective when there is firm power *** least competitive nuclear option plays this role and reduces system costs by 16.4%,curtails the annual main node by 36.8%,and decreases the CAES capacity requirements by≤80.7%in the case of a double-load *** CAES has potential in addressing renewable variability,its widespread deployment is constrained by geographical,societal,and economic fac***,if California is aiming for an energy system that is reliant on wind and solar power,then an additional dispatchable power source other than CAES or similar load flexibility is *** fully harness the benefits of bulk CAES,the development and implementation of cost-effective approaches are crucial in significantly reducing system costs.

关键词： compressed-air energy storage deep decarbonization macro-energy modelling load growth renewable energy

A Unified Optimization-Based Framework to Adjust Consensus Convergence Rate and Optimize the Network Topology in Uncertain Multi-Agent Systems

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IEEE/CAA Journal of Automatica Sinica 2021年第9期8卷 1539-1548页

作者： mohammad Saeed Sarafraz mohammad Saleh Tavazoei Department of Electrical Engineering Sharif University of TechnologyTehran 11365-9363Iran

This paper deals with the consensus problem in an uncertain multi-agent system whose agents communicate with each other through a weighted undirected(primary)*** considered multi-agent system is described by an uncertain state-space model in which the involved matrices belong to some matrix *** the main contribution of the paper,a unified optimization-based framework is proposed for simultaneously reducing the weights of the edges of the primary communication graph(optimizing the network topology)and synthesizing a controller such that the consensus in the considered uncertain multi-agent system is ensured with an adjustable convergence *** the NP-hardness nature of the optimization problem related to the aforementioned framework,this problem is relaxed such that it can be solved by regular LMI ***/practical-based examples are presented to verify the usefulness of the obtained results.

关键词： Convergence-rate element-wise uncertainty robust controller topology design

Socio-political and ecological stresses on traditional pastoral systems:A review

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Journal of Geographical Sciences 2019年第10期29卷 1758-1770页

作者： MUHAMMAD Khurshid mohammad Nafees ABDULLAH Khan MEHMET Somuncu ashfaq Ahmad Khan WAJID Rashid Department of Environmental Sciences The University of HaripurKhyber Pakhtunkhwa 22620 Pakistan Department of Environmental Sciences University of PeshawarPeshawar 25000 Pakistan Department of Geography Ankara UniversitySihhiye 06100 Ankara Turkey Department of Geography Karabuk UniversityKarabuk 78000 Turkey Department of Environmental Sciences The University of SwatSwat 19130 Pakistan

Pastoralism is a viable socio-economic system-shaped by landless and agro-pastoral communities in many pastoral regions of the world. This system is mainly based on seasonal migration of pastoralists and their livestock herds between upland and lowland pastures. Traditionally pastoral activities make significant contributions to mountain livelihood subsistence, regional economies and environmental sustainability. However, the pastoralist’s lifestyle and their economies are increasingly confronted to various socio-political, economic and ecological stresses from the last few decades. Extensive literature reviewed on this subject with the aim to explore the current emerging challenges faced by pastoral communities in different pastoral regions. It has been revealed from literature that the prevalent socio-political and economic stress on pastoralism caused by modernization, insecure land tenure, integration of market economy, civil insecurities and pastoralist’s exclusion in states policies while ecological stress on pastoral activities emerged with increasing focus on nature conservation in pastoral regions and climate change induced hazards and disasters. As a consequence of these challenges, pastoral households are abandoning livestock herding–as a traditional way of life and are in continuous transition to transform their pastoral practices and institutions. Thus, the attention and consultation of key stakeholders are needed toward pastoral resource development that improve and sustain traditional pastoral practices in a socio-politically and ecologically stressed environment of the world.

关键词： pastoralism marginalization pastoral system pastures livestock pastoralists

A fast and accurate dynamic relaxation scheme

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Frontiers of Structural and Civil Engineering 2019年第1期13卷 176-189页

作者： mohammad REZAIEE-PAJAND mohammad mohammadI-KHATAMI Department of Civil Engineering Ferdowsi University of MashhadMashhadIran

Dynamic relaxation method (DRM)is one of the suitable numerical procedures for nonlinear structural *** the fictitious inertia and damping forces to the static equation,and turning it to the dynamic system,are the basis of this *** selection of the DRM artificial factors leads to the better convergence rate and efficient *** study aims to increase the numerical stability,and to decrease the analysis *** fulfil this objective,the reduction rate of analysis error for consecutive iterations is *** on this formulation,a new time step is found for the viscous dynamic *** combining this novel relationship with the other DRM factors,various geometrical nonlinear structures,such as trusses,frames,and shells,are *** obtained results verify the efficiency of authors'scheme.

关键词： viscous dynamic relaxation time step displacement error geometric nonlinear analysis

Biomechanics of knee joint during forward-walking and drop-landing after anterior cruciate ligament reconstruction:finite element and gait analysis

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Acta Mechanica Sinica 2024年第11期40卷 53-75页

作者： Midiya Khademi mohammad Haghpanahi mohammad Razi Ali Sharifnezhad mohammad Nikkhoo Department of Biomedical Engineering Science and Research BranchIslamic Azad UniversityTehran ***Iran Department of Mechanical Engineering Iran University of Science and TechnologyTehran ***Iran Department of Orthopedics Iran University of Medical SciencesTehran ***Iran Department of Sport Biomechanics and Technology Sport Science Research InstituteTehran ***Iran

The anterior cruciate ligament plays a crucial role in maintaining stability within the knee joint,particularly for athletes who frequently experience its *** study presents a novel approach using personalized three-dimensional(3D)parametric finite element modeling of the knee joint to simulate the treatment following anterior cruciate ligament reconstruction(ACLR)in both forward walking(FW)and drop landing(DL)*** study encompasses two distinct cohorts:five healthy athletes and five ACLR *** motion analysis was conducted on both cohorts,with the ACLR patient group evaluated at 6 and 9 months post-surgery.A comprehensive 3D parametric model of the knee joint was meticulously *** findings reveal a notable reduction in stress on crucial knee structures such as the autograft,meniscus,and cartilages over time for both FW and DL tasks following ACLR,with a reduction in tissue tension of approximately 9.5%and 37%for FW and DL,*** personalized model not only facilitates the investigation of knee joint tissue biomechanics post-ACLR but also aids in estimating the return-to-sports timeline for *** accommodating individual tissue geometries and incorporating patient-specific kinetic data,this model enhances our comprehension of post-ACLR biomechanics across various functional tasks,thereby optimizing rehabilitation strategies.

关键词： Anterior cruciate ligament reconstruction(ACLR) Forward walking(FW) Drop landing(DL) Knee finite element model Gait analysis

Particle swarm optimization algorithm for simultaneous optimal placement and sizing of shunt active power conditioner(APC)and shunt capacitor in harmonic distorted distribution system

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Journal of Central South University 2017年第9期24卷 2035-2048页

作者： mohammadi mohammad Department of Electrical Engineering Borujerd BranchIslamic Azad UniversityBorujerdIran

Due to development of distribution systems and increase in electricity demand,the use of capacitor banks *** the other point of view,nonlinear loads generate and inject considerable harmonic currents into power *** this condition if capacitor banks are not properly selected and placed in the power system,they could amplify and propagate these harmonics and deteriorate power quality to unacceptable *** attention of disadvantages of passive filters,such as occurring resonance,nowadays the usage of this type of harmonic compensator is *** the other side,one of parallel multi-function compensating devices which are recently used in distribution system to mitigate voltage sag and harmonic distortion,performs power factor correction,and improves the overall power quality as active power conditioner(APC).Therefore,the utilization of APC in harmonic distorted system can affect and change the optimal location and size of shunt capacitor bank under harmonic distortion *** paper presents an optimization algorithm for improvement of power quality using simultaneous optimal placement and sizing of APC and shunt capacitor banks in radial distribution networks in the presence of voltage and current *** algorithm is based on particle swarm optimization(PSO).The objective function includes the cost of power losses,energy losses and those of the capacitor banks and APCs.

关键词： shunt capacitor banks active power conditioner multi-objective function particle swarm optimization (PSO) harmonic distorted distribution system

IMC based robust PID controller tuning for disturbance rejection

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Journal of Central South University 2016年第3期23卷 581-597页

作者： mohammad Shamsuzzoha Department of Chemical Engineering King Fahd University of Petroleum and Minerals

It is well-known that the IMC-PID controller tuning gives fast and improved set point response but slow disturbance rejection. A modification has been proposed in IMC-PID tuning rule for the improved disturbance rejection. For the modified IMC-PID tuning rule, a method has been developed to obtain the IMC-PID setting in closed-loop mode without acquiring detailed information of the process. The proposed method is based on the closed-loop step set point experiment using a proportional only controller with gain K_(c0). It is the direct approach to find the PID controller setting similar to classical Ziegler-Nichols closed-loop method. Based on simulations of a wide range of first-order with delay processes, a simple correlation has been derived to obtain the modified IMC-PID controller settings from closed-loop experiment. In this method, controller gain is a function of the overshoot obtained in the closed loop set point experiment. The integral and derivative time is mainly a function of the time to reach the first peak(overshoot). Simulation has been conducted for the broad class of processes and the controllers were tuned to have the same degree of robustness by measuring the maximum sensitivity, Ms, in order to obtain a reasonable comparison. The PID controller settings obtained in the proposed tuning method show better performance and robustness with other two-step tuning methods for the broad class of processes. It has also been applied to temperature control loop in distillation column model. The result has been compared to the open loop tuning method where it gives robust and fast response.

关键词： PI/PID controller step test closed-loop response IMC-PID overshoot