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Discrete time multiple spacecraft formation flying attitude optimal control in presence of relative state constraints

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Chinese Journal of Aeronautics 2021年第4期34卷 293-305页

作者： hossein MORADI PARI hossein BOLANDI Department of Electrical Engineering Iran University of Science and TechnologyTehran 009821Iran

This paper addresses the challenge of synchronized multiple spacecraft attitude reorientation in presence of pointing and boundary constraints with limited inter-spacecraft communication *** attitude pointing constraint among the fleet of spacecraft has also been modeled and considered during the attitude maneuvers toward the desired *** fling control structure that consists of decentralized path planners based on virtual structure approach joint with discrete time optimal local controller is designed to achieve the mission's *** to digital computing of spacecraft's onboard computer,local optimal controller based on discrete time prediction and correction algorithm has been *** time step of local optimal algorithm execution is designed so that the spacecraft track their desired attitudes with appropriate error *** convergence of the proposed architecture and stability of local controller's tracking error within appropriate upper bound are ***,a numerical simulation of a stereo imaging scenario is presented to verify the performance of the proposed architecture and the effectiveness of the algorithm.

关键词： Decentralized Discrete time Formation flying Optimal control Spacecraft Virtual structure approach

Effect of different treatments on electrokinetic remediation of Zn, Pb and Cd from a contaminated calcareous soil

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Chinese Journal of Chemical Engineering 2021年第10期34卷 255-265页

作者： hossein Beyrami National Salinity Research Center Agricultural ResearchEducation and Extension OrganizationYazdIran

Electrokinetic remediation is a promising method to decontamination of the heavy metals from *** this paper,the remediation of a contaminated calcareous soil with Zn,Cd and Pb sampled from around Zanjan province of Iran,was investigated using electrokinetic *** this paper,the soil contain a high concentration of Zn(1400 mg·kg^(-1)),Cd(15 mg·kg^(-1))and Pb(250 mg·kg^(-1)).Electrokinetic decontamination consists of two series of experiments as follows:(1)the effect of five treatments including the use of distilled water,acetic acid and EDTA electrolyte solutions,and approaching anodes systems,and the circulation flow of electrolyte at two different voltage gradient(i.e.1.33 and 2.66 V·cm^(-1)),and(2)the effect of moisture content(saturated,FC and 0.7 FC,FC indicated soil moisture at "Field Capacity")with a voltage gradient of 1.33 V·cm^(-1).After applying electric current for 5 days,the results of experiments indicated that the removal efficiency of heavy metals can be increased by raising the voltage *** this matter,the highest remediation can be observed among different treatments in EDTA(Ethylene diamine tetra acetic acid)treatment(40.11%,43.10%and 24.7%for Zn,Cd and Pb,respectively).Moreover,the heavy metals removal at the saturated moisture was at the highest level so that 32.62%cadmium,31.33%zinc and 18.82%lead being removed after 120 h of electric current *** decreasing moisture to 0.7 FC,the removal percentage for the three heavy metals obtained 20.97%,18.44%and 12.25%,***,Cd had the highest removal,and Zn and Pb were next among the three heavy metals in question.

关键词： Decontamination Soil moisture Voltage gradient Cadmium Lead Zinc

Effects of Location,Size and Number of Wind Turbine Receptors on Blade Lightning Protection

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电力系统自动化 2012年第8期36卷 122-127页

作者： hossein Kazemi KAREGAR hossein BAGHERIAN Faculty of Electrical &Computer Engineering Shahid Beheshti University

Electric and magnetic fields generated by lightning cause a serious hazard to various *** wind turbine installations with higher power capacity are *** power capacity requires higher height and so there is more probability of lightning *** are the most probable components to be struck by *** most common lightning protection system for the blades consists of several metallic receptors on the blade *** are connected to the ground by metallic down-conductors placed inside the blade *** paper studies effects of the receptor configurations on protecting the blade against lightning *** this purpose,an analysis procedure based on finite element method(FEM)in COMSOL Multiphysics software environment is *** voltage distribution around the blade is simulated for various configurations of *** best configuration is *** are performed on the blade model of a special wind turbine,which isVESTAS V47".

关键词：风力发电机组受体刀片防雷叶片表面位置最佳配置发电能力

REMOVAL OF MERCURY FROM WATER USING POLYPYRROLE AND ITS COMPOSITES

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Chinese Journal of Polymer Science 2007年第4期25卷 393-397页

作者： hossein Eisazadeh Faculty of Chemical Engineering University of MazandaranP.O.Box 484BabolIran

One of the suitable methods for removing heavy metals from water is by using surface adsorption process. In this paper, the preparation of polypyrrole and its composites as adsorbents are discussed and the capability of separating mercury from water is investigated. The results indicated that the polypyrrole and its composites are able to remove mercury from aqueous media. Furthermore the adsorption percentage is related to the surface morphology, type of additives and its concentration.

关键词： Polypyrrole and its composites Mercury removal Additives Surface morphology.

Thermodynamics of 4D dS/AdS Gauss–Bonnet black holes according to consistent gravity theory in the presence of a cloud of strings

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Communications in Theoretical Physics 2022年第4期74卷 72-84页

作者： hossein Ghaffarnejad Faculty of Physics Semnan UniversityP.C.35131-19111SemnanIran

By looking at the Lovelock theorem one can infer that the gravity model given by[1]cannot be applicable for all types of 4D Einstein–Gauss–Bonnet(EGB)curved *** reason for this is that in 4D space-time,the Gauss–Bonnet invariant is a total derivative and hence it does not contribute to gravitational ***,the authors of[2]presented an alternative consistent EGB gravity model instead of[1]by applying a break-of-diffeomorphism *** this work,we use the alternative model to produce a de Sitter(dS)/Anti-de Sitter(AdS)black hole metric and then investigate its thermodynamic behavior in the presence of a cloud of Nambu–Goto *** derivations show that the resulting diagrams of pressure vs specific volume at a constant temperature are similar to that for a van der Waals gas/fluid in an ordinary thermodynamic system in the d S sector but not in the Ad S *** this,we infer that the black hole participates in the small-to-large black hole phase transition in the dS background,while it exhibits a Hawking–Page phase transition in the AdS *** the latter case,an evaporating black hole eventually reaches an AdS vacuum space because of its instability.

关键词： Lovelock gravity string Nambu-Goto Gauss-Bonnet black hole thermodynamic cosmological constant phase transition

Correlation of the mean activity coefficient of aqueous electrolyte solutions using an equation of state

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Chinese Journal of Chemical Engineering 2016年第10期24卷 1456-1463页

作者： Seyed hossein Mazloumi Chemical Engineering Department Faculty of EngineeringFerdowsi University of Mashhad

Accurate calculation of thermodynamic properties of electrolyte solution is essential in the design and optimization of many processes in chemical industries. A new electrolyte equation of state is developed for aqueous electrolyte solutions. The Carnahan-Starling repulsive model and an attractive term based on square-well potential are adopted to represent the short range interaction of ionic and molecular species in the new electrolyte EOS. The long range interaction of ionic species is expressed by a simplified version of Mean Spherical Approximation theory （MSA）. The new equation of state also contains a Born term for charging free energy of ions. Three adjustable parameters of new eEOS per each electrolyte solution are size parameter, square-well potential depth and square-well potential interaction range. The new eEOS is applied for correlation of mean activity coefficient and prediction of osmotic coefficient of various strong aqueous electrolyte solutions at 25℃ and 0.1 MPa. In addition, the extension of the new eEOS for correlation of mean activity coefficient and solution density of a few aqueous electrolytes at temperature range of 0 to 100℃ is carried out.

关键词： Aqueous electrolyte solution Electrolyte equation of state Activity coefficient Osmotic coefficient Solution density

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Journal of Systems Science & Complexity 2014年第1期27卷 3-20页

作者： HASSANI hossein ABDOLLAHZADEH Majid IRANMANESH hossein MIRANIAN Arash Executive Business Centre Bournemouth University Bournemouth 89 Holdenhurst Road BH8 8EB UK. Department of Mechanical Engineering Pard@ Branch Islamic Azad University Pardis new city TehranIran. Department of Industrial Engineering College of Engineering University of Tehran Iran Institute of Inter-national Energy Studies ( IIES) Tehran Iran. Department of Mechanical Engineering Pardis Branch Islamic Azad University Pardis New City TehranIran.

This paper proposes a selfsimilar local neurofuzzy （SSLNF） model with mutual informati onbased input selection algorithm for the shortterm electricity demand forecasting. The proposed self similar model is composed of a number of local models, each being a local linear neurofuzzy （LLNF） model, and their associated validity functions and can be interpreted itself as an LLNF model. The proposed model is trained by a nested local liner model tree （NLOLIMOT） learning algorithm which partitions the input space into axisorthogonal subdomains and then fits an LLNF model and its associated validity function on each subdomain. Furthermore, the proposed approach allows different input spaces for rule premises （validity functions） and consequents （local models）. This appealing property is employed to assign the candidate input variables （i.e., previous load and temperature） which influence shortterm electricity demand in linear and nonlinear ways to local models and validity functions, respectively. Numerical results from shortterm load forecasting in the New England in 2002 demonstrated the accuracy of the SSLNF model for the STLF applications.

关键词： Mutual information self-similar local neuro-fuzzy model short-term load forecasting.

Thermal Analysis Simulation of Germanium Zone Refining Process Assuming a Constant Radio-Frequency Heating Source

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Chinese Physics Letters 2016年第5期33卷 123-126页

作者： Mahdi Ezheiyan hossein Sadeghi Mohammad-hossein Tavakoli Department of Physics Malek-Ashtar University of Technology Department of Physics Bu-Ali Sina University

Three-dimensional thermal a nalysis simulation of a horizontal zone refining system is conducted for germanimn semiconductor materials. The considered geometry includes a g＇ral）hite boat filled with germanium placed in a cylindrical quartz tube. A flow of Ar and H2 gas mixture is purged througll the tube. A narrow section of the, boat is assmned to be exposed to a constant heat rate produced b v an rf coil located outside the quartz tube. The results of this analysis provide essential information about various parameters such as the shape of tile molten zone, required power and temperature gradient in the system.

关键词： of on Thermal Analysis Simulation of Germanium Zone Refining Process Assuming a Constant Radio-Frequency Heating Source in is for

Biostratigraphy and Sequence Stratigraphy of the Tarbur Formation(Maastrichtian)from Iranian Zagros Foreland Basin,Southwest of Iran

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Acta Geologica Sinica(English Edition) 2022年第1期96卷 147-166页

作者： hossein GHANBARLOO Amrollah SAFARI hossein VAZIRI-MOGHADDAM Department of Geology University of IsfahanIsfahanIran

Shallow carbonate deposits(Tarbur Formation)were formed in the Zagros foreland basin with dynamic tectonics during the Maastrichtian *** the viewpoint of reconstruction of depositional conditions in these deposits,studies of biostratigraphy,microfacies,microtaphofacies,and sequence stratigraphy were performed in a single area at Tang-e Shabi Khoon,northwest of *** on the identification of two assemblage zones consisting of benthic foraminifera in these strata,the formation was deposited during the middle to late *** number of cycles in test size and type of coiling in Loftusia decreased from the study area toward the northwest of the Neotethys *** input of clastic sediments affected the distribution of Loftusia and rudists in the study *** microfacies,six microtaphofacies,and one terrigenous facies(shale)were identified based on the sedimentary *** deposits of the middle-late Maastrichtian were deposited on a homoclinal carbonate *** platform can be divided into restricted and semi-restricted lagoon,shoal,and open marine *** the study area,the deposits of the Tarbur Formation were deposited during four third-order depositional *** fault activities affected the formation of depositional sequences in the study area.

关键词： biostratigraphy microfacies microtaphofacies rudist patchy reef ramp Tarbur Formation Maastrichtian