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Optimization of passive control performance for different hard disk drives subjected to shock excitation

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Journal of Central South University 2017年第4期24卷 891-899页

作者： seyed Rashid Alavi Mehdi Rahmati saeed Ziaei-Rad Department of Mechanical Engineering Isfahan University of Technology Isfahan 84156-83111 Iran Isfahan Mathematics House Isfahan 81698-51177 Iran

Laptop personal computers(LPCs) and their components are vulnerable devices in harsh mechanical environments. One of the most sensitive components of LPCs is hard disk drive(HDD) which needs to be protected against damages attributable to shock and vibration in order to have better magnetic read/write performance. In the present work, a LPC and its HDD are modeled as two degrees of freedom system and the nonlinear optimization method is employed to perform a passive control through minimizing peak of HDD absolute acceleration caused by a base shock excitation. The presented shock excitation is considered as half-sine pulse of acceleration. In addition, eleven inequality constraints are defined based on geometrical limitations and allowable intervals of lumped modal parameters. The target of the optimization is to reach optimum modal parameters of rubber mounts and rubber feet as design variables and subsequently propose new characteristics of rubber mounts and rubber feet to be manufactured for the HDD protection against shock excitation. The genetic algorithm and the modified constrained steepest descent algorithm are employed in order to solve the nonlinear optimization problem for three widely-used commercial cases of HDD. Finally, the results of both optimization methods are compared to make sure about their accuracy.

关键词： hard disk drive passive control shock excitation sequential quadratic programming genetic algorithm rubber

Energy Management of Networked Smart Railway Stations Considering Regenerative Braking, Energy Storage System, and Photovoltaic Units

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Energy Engineering 2023年第1期120卷 69-86页

作者： saeed Akbari seyed saeed Fazel Hamed Hashemi-Dezaki School of Railway Engineering Iran University of Science and TechnologyTehran13114-16846Iran Department of Electrical and Computer Engineering University of KashanKashan***Iran Research and Innovational Center for Electrical Engineering(RICE) Faculty of Electrical EngineeringUniversity ofWest Bohemia(UWB)Pilsen30100Czech Republic

The networking of microgrids has received significant attention in the form of a smart *** this paper,a set of smart railway stations,which is assumed as microgrids,is connected *** has been tried to manage the energy exchanged between the networked microgrids to reduce received energy from the utility ***,the operational costs of stations under various conditions decrease by applying the proposed *** smart railway stations are studied in the presence of photovoltaic(PV)units,energy storage systems(ESSs),and regenerative braking *** regenerative braking is one of the essential ***,the stochastic behaviors of the ESS’s initial state of energy and the uncertainty of PV power generation are taken into account through a scenario-based *** networked microgrid scheme of railway stations(based on coordinated operation and scheduling)and independent operation of railway stations are *** proposed method is applied to realistic case studies,including three stations of Line 3 of Tehran Urban and Suburban Railway Operation Company(TUSROC).The rolling stock is simulated in the MATLAB ***,the coordinated operation of networked microgrids and independent operation of railway stations are optimized in the GAMS environment utilizing mixed-integer linear programming(MILP).

关键词： Energy management system(EMS) smart railway stations coordinated operation photovoltaic generation regenerative braking uncertainty scenario-based model mixed-integer linear programming(MILP)

Kinetic modeling of copper bioleaching from low-grade ore from the Shahrbabak Copper Complex

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International Journal of Minerals,Metallurgy and Materials 2017年第6期24卷 611-620页

作者： Saman Beikzadeh Noei saeed Sheibani Fereshteh Rashchi seyed Mohammad Javad Mirazimi School of Metallurgy and Materials Engineering College of Engineering University of Tehran Tehran 13145-1318 Iran

The copper recovery from low-grade copper sulfide ore was investigated using microbial leaching. Several parameters substantially affect the bioleaching of copper; among them, pulp density and nutrient media were selected for investigation. The optimum conditions for copper recovery were a pulp density of 5 g/mL, a mixed-mineral salt medium of Acidithiobacillus thiooxidans(70vol%) and Acidithiobacillus ferrooxidans(30vol%), and 10vol% of inoculum. Under these conditions, the maximum bioleaching capacity of the medium for copper recovery was determined to be approximately 99%. The effect of pulp density on the kinetics of the bioleaching process was surveyed using both da Silva's method and constrained multilinear regression analysis. The kinetics of copper dissolution followed the shrinking core model, and the process was diffusion controlled at a pulp density of 5 g/mL. Nevertheless, at higher pulp densities, the process was controlled by chemical reaction.

关键词： bioleaching kinetics modeling copper mesophilic bacteria

Sediment contribution from different geologic formations and land uses in an Iranian small watershed,case study

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International Journal of Sediment Research 2017年第2期32卷 210-220页

作者： seyed Hamidreza Sadeghi saeed Najafi Alireza Riyahi Bakhtiari Department of Watershed Management Engineering Faculty of Natural ResourcesTarbiat Modares University Department of Environmental Sciences Faculty of Natural ResourceTarbiat Modares University

Many intra and extra problems occurred due to unsustainable human use of natural resources leading to increasing sediment loads in the ***,few studies have been comprehensively conducted in progressing countries to prioritize sediment sources from different points of views,particularly in some countries like Iran where such valuable information is essential for proper watershed resources *** present study was therefore planned to assess the importance of potential sediment sources viz.,spatial sources(geologic units) and source types(land use units) in sediment yield in Idelo watershed as one of the important sub-watersheds of Sefidrood large Watershed in Zanjan Province,Iran,using composite *** addition,the results of the sediment fingerprinting approach were compared with those of field measurement data obtained from studying soil erosion types(viz.,sheet,rill and gully erosion).Toward this attempt,16 tracers were detected in different geologic units and land uses and the sediment yielded at the watershed *** results showed that the composite fingerprints of the different geologic units comprising As,N,Cu,Zn,OC and Co tracers could correctly distinguish 86% of the sediment source *** red gypsiferous marl contributed 85 percent in sediment *** regard to source types,the optimum composite fingerprint encompassed only N and Cu and provided a discriminatory efficiency of 90%.Besides that,the rangelands with 48.8% study area coverage had a significant contribution of 88% in sediment *** field measurements confirmed the reliability of results of fingerprinting approach in apportioning watershed scale sediment sources on the base of consistency of the two sets of *** was also understood from the results,besides successful applicability of composite fingerprinting in assessing the provenance of the sediment yielded at the watershed outlet that the geologic formations and land use types played differe

关键词： Composite fingerprinting Multivariate mixing model Soil erosion Spatial sources Source types

Tribological behaviour of AZ31 magnesium alloy reinforced by bimodal size B_(4)C after precipitation hardening

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Journal of Magnesium and Alloys 2022年第11期10卷 3267-3280页

作者： seyed Kiomars Moheimani Azadeh Keshtgar saeed Khademzadeh Morteza Tayebi Ali Rajaee Abdollah Saboori Advanced Materials Research Center Department of Materials EngineeringNajafabad BranchIslamic Azad UniversityNajafabadIran Department of Research and Development Nejat Darya CompanyBoushehrIran Center for Risk and Reliability University of MarylandCollege ParkMD 20742United States Department of Industrial Engineering University of Padova35131 PadovaItaly Young Researchers and Elites Club Science and Research BranchIslamic Azad UniversityTehranIran Department of Materials and Polymer Engineering Hakim Sabzevari UniversitySabzevarIran Integrated Additive Manufacturing Center(IAM) Department of Management and Production Engineering(DIGEP)Politecnico di TorinoCorso Duca Degli Abruzzi2410129TorinoItaly

This study investigated dry sliding wear properties of AZ31 magnesium alloy and B_(4)C-reinforced AZ31 composites containing 5, 10, and 20 wt.% B_(4)C with bimodal sizes under different loadings(10-80 N) at various sliding speeds(0.1-1 m/s) via the pin-on-disc *** evaluations showed that when the distribution of B_(4)C particles was uniform the hardness of the composites increased by enhancing the reinforcement content. The unreinforced alloy and the composite samples were examined to determine the wear mechanism maps and identify the dominant wear mechanisms in each wear condition and reinforcement content. For this purpose, wear rates and friction coefficients were recorded during the wear tests and worn surfaces were characterized by scanning electron microscopy and energy dispersive X-ray spectrometry analyses. The determined wear mechanisms were abrasion, oxidation, delamination, adhesion, and plastic deformation as a result of thermal softening and melting. The wear evaluations revealed that the composites containing 5 and 10 wt.% B_(4)C had a significantly higher wear resistance in all the conditions. However, 20 wt.% B_(4)C/AZ31 composite had a lower resistance at high sliding speeds(0.5-1 m/s) and high loadings(40-80 N) in comparison with the unreinforced alloy. The highest wear resistance was obtained at high sliding speeds and low loadings with the domination of oxidative wear.

关键词： B_(4)C AZ31 alloy Metal matrix composite Wear mechanism Bimodal

Incorporating microgrids coupling with utilization of flexible switching to enhance self-healing ability of electric distribution systems

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Protection and Control of Modern Power Systems 2021年第1期6卷 300-310页

作者： saeed Mousavizadeh Arman Alahyari seyed Reza Movahhed Ghodsinya Mahmoud-Reza Haghifam Faculty of Electrical and Computer Engineering Tarbiat Modares UniversityPO Box 14115-111TehranIran Skolkovo Institute of Science and Technology(Skoltech) MoscowRussia Department of Electrical Engineering University of Torbat HeydariehTorbat HeydariehIran

Electric distribution networks have to deal with issues caused by natural disasters. These problems possess unique characteristics, and their severity can make load restoration methods impotent. One solution that can help in alleviating the aftermath is the use of microgrids (MGs). Employing the cumulative capacity of the generation resources through MG coupling facilitates the self-healing capability and leads to better-coordinated energy management during the restoration period, while the switching capability of the system should also be considered. In this paper, to form and schedule dynamic MGs in distribution systems, a novel model based on mixed-integer linear programming (MILP) is proposed. This approach employs graph-related theories to formulate the optimal formation of the networked MGs and management of their proper participation in the load recovery process. In addition, the Benders decomposition technique is applied to alleviate computability issues of the optimization problem. The validity and applicability of the proposed model are evaluated by several simulation studies.

关键词： Load restoration Distribution network Microgrids coupling Benders decomposition

Multi-objective design optimization of a large-scale directdrive permanent magnet generator for wind energy conversion systems

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Frontiers in Energy 2014年第2期8卷 182-191页

作者： Arash Hasssanpour ISFAHANI Amirhossein Haji-seyed BOROUJERDI saeed HASANZADEH Everette Energy LLC Dallas 75225 USA Faculty of Electrical and Engineering Islamic Azad University Islamshahr Branch Tehran 33147-67653 Iran Facuty of Electrical and Computer Engineering Qom University of Technology Qom 1519-37195 Inan

This paper presents a simukaneous multi- objective optimization of a direct-drive permanent magnet synchronous generator and a three-blade horizontal-axis wind turbine for a large scale wind energy conversion system. Analytical models of the generator and the turbine are used along with the cost model for optimization. Three important characteristics of the system i.e.,the total cost of the generator and blades, the annual energy output and the total mass of generator and blades are chosen as objective functions for a multi-objective optimization. Genetic algorithm （GA） is then employed to optimize the value of eight design parameters including seven generator parameters and a turbine parameter resulting in a set of Pareto optimal solutions. Four optimal solutions are then selected by applying some practical restrictions on the Pareto front. One of these optimal designs is chosen for finite element verification. A circuit-fed coupled time stepping finite element method is then performed to evaluate the no-load and the full load performance analysis of the system including the generator, a rectifier and a resistive load. The results obtained by the finite element analysis （FEA） verify the accuracy of the analytical model and the proposed method.

关键词： permanent magnet synchronous generator wind turbine direct-drive multi-objective optimization,

Warpage and Shrinkage Optimization of Injection-Molded Plastic Spoon Parts for Biodegradable Polymers Using Taguchi, ANOVA and Artificial Neural Network Methods

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Journal of Materials Science & Technology 2016年第8期32卷 710-720页

作者： Erfan Oliaei Behzad Shiroud Heidari seyed Mohammad Davachi Mozhgan Bahrami saeed Davoodi Iman Hejazi Javad Seyfi Applied Science Nano Research Group ASNARKA P.C. *** Tehran Iran Macromolecular Science and Engineering University of Michigan Ann Arbor Michigan 48109-2136. United States Department of Chemical Engineering Shahrood Branch Islamic Azad University RO. Box 36155-163 Shahrood lran

In this study, it is attempted to give an insight into the injection processability of three self-prepared polymers from A to Z. This work presents material analysis, injection molding simulation, design of ex- periments alongside considering all interaction effects of controlling parameters carefully for green biodegradable polymeric systems, including polylactic acid （PLA）, polylactic acid-thermoplastic poly- urethane （PLA-TPU） and polylactic acid-thermoplastic starch （PLA-TPS）. The experiments were carried out using injection molding simulation software Autodesk Moldflov~~ in order to minimize warpage and volumetric shrinkage for each of the mentioned systems. The analysis was conducted by changing five significant processing parameters, including coolant temperature, packing time, packing pressure, mold temperature and melt temperature. Taguchi＇s [.27 （35） orthogonal array was selected as an efficient method for design of simulations in order to consider the interaction effects of the parameters and reduce spu- rious simulations. Meanwhile, artificial neural network （ANN） was also used for pattern recognition and optimization through modifying the processing conditions. The Taguchi coupled analysis of variance （ANOVA） and ANN analysis resulted in definition of optimum levels for each factor by two completely different methods. According to the results, melting temperature, coolant temperature and packing time had significant influence on the shrinkage and warpage. The ANN optimal level selection for minimiza- tion of shrinkage and/or warpage is in good agreement with ANOVA optimal level selection results. This investigation indicates that PLA-TPU compound exhibits the highest resistance to warpage and shrink- age defects compared to the other studied compounds.

关键词： Injection molding simulation Yaguchi Artificial neural networks Biodegradable plastic Disposable spoons

Performance and emission characteristics of a diesel engine operating on different water in diesel emulsion fuels:optimization using response surface methodology(RSM)

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Frontiers in Energy 2019年第4期13卷 636-657页

作者： seyed saeed HOSEINI Mohammad Amin SOBATI School of Chemical Engineering Iran University of Science and Technology(IUST)Tehran 16765163Iran

The nitrogen oxide(NOx)release of diesel engines can be reduced using water in diesel emulsion fuel without any engine *** the present paper,different formulations of water in diesel emulsion fuels were prepared by ultrasonic *** water droplet size in the emulsion,polydisperisty index,and the stability of prepared fuel was examined,***,the performance characteristics and exhaust emission of a single cylinder air-cooled diesel engine were investigated using different water in diesel emulsion *** effect of water content(in the range of 5%-10% by volume),surfactant content(in the range of 0.5%-2% by volume),and hydrophilic-lipophilic balance(HLB)(in the range of 5-8)was examined using Box-Behnken design(BBD)as a subset of response surface methodology(RSM).Considering multi-objective optimization,the best formulation for the emulsion fuel was found to be 5%water,2% surfactant,and HLB of 6.8.A comparison was made between the best emulsion fuel and the neat diesel fuel for engine performance and emission characteristics.A considerable decrease in the nitrogen oxide emission(-18.24%)was observed for the best emulsion fuel compared to neat diesel fuel.

关键词： water in diesel emulsion fuel hydrophiliclipophilic balance(HLB) response surface methodology(RSM) emulsion stability engine performance exhaust emission