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Fe^(3+)-Doped Anatase TiO_2 Study Prepared by New Sol-Gel Precursors

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Chinese Physics Letters 2018年第2期35卷 102-106页

作者： Bahram khoshnevisan Mohammad Bagher Marami Majid Farahmandjou Department of Physics Faculty of ScienceUniversity of Kashan Departments of Physics Varamin Pishva BranchIslamis Azad University

FeTi_1-O_2（= 0.00,0.05,0.10） nanocomposites are synthesized using a sol-gel method involving an ethanol solvent in the presence of ethylene glycol as the stabilizer,and acetic acid as the chemical *** structural and optical analyses are studied to reveal their physicochemical *** the x-ray diffractometer（XRD）analysis,the size of the nanoparticles（NPs） is found to be 18-32 nm,where the size of the NPs decreases down to 18 nm when Fe impurity of up to 10% is added,whereas their structure remains *** results also indicate that the structure of the NPs is tetragonal in the anatase *** Fourier transform infrared spectroscopy analysis suggests the presence of a vibration bond（Ti-O） in the *** photoluminescence analysis indicates that the diffusion of Fe^（3＋） ions into the TiO_2 matrix results in a decreasing electron-hole recombination,and increases the photocatalytic properties,where the best efficiency appears at an impurity of10%.The UV-diffuse reflection spectroscopy analysis indicates that with the elevation of iron impurity,the band gap value decreases from 3.47 eV for the pure sample to 2.95 eV for the 10 mol% Fe-doped TiO_2 NPs.

关键词： Fe Doped Anatase TiO2 Study Prepared by New Sol-Gel Precursors TiO

An Improved Farmland Fertility Algorithm with Hyper-Heuristic Approach for Solving Travelling Salesman Problem

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Computer Modeling in Engineering & Sciences 2023年第6期135卷 1981-2006页

作者： Farhad Soleimanian Gharehchopogh benyamin Abdollahzadeh Bahman Arasteh Department of Computer Engineering Urmia BranchIslamic Azad UniversityUrmiaIran Department of Software Engineering Faculty of Engineering and Natural ScienceIstinye UniversityIstanbulTurkey

Travelling Salesman Problem(TSP)is a discrete hybrid optimization problem considered *** aims to discover the shortest Hamilton route that visits each city precisely once and then returns to the starting point,making it the shortest route *** paper employed a Farmland Fertility Algorithm(FFA)inspired by agricultural land fertility and a hyper-heuristic technique based on the Modified Choice Function(MCF).The neighborhood search operator can use this strategy to automatically select the best heuristic method formaking the best ***-Kernighan(LK)local search has been incorporated to increase the efficiency and performance of this suggested approach.71 TSPLIB datasets have been compared with different algorithms to prove the proposed algorithm’s performance and *** results indicated that the proposed algorithm outperforms comparable methods of average mean computation time,average percentage deviation(PDav),and tour length.

关键词： Travelling salesman problem optimization farmland fertility optimization algorithm Lin-Kernighan

Correlations between various rock mass classification/characterization systems for the Zagros tunnel-W Iran

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Journal of Mountain Science 2020年第7期17卷 1790-1806页

作者： Shahriar SADEGHI Ebrahim SHARIFI TESHNIZI benyamin GHOREISHI Department of Geology Faculty of scienceImam Khomeini International UniversityQazvin34149-16818Iran Engineering Geology Young Researchers and Elite ClubShahrekord BranchIslamic Azad UniversityShahrekord15655-461Iran

This study deals with the comparative investigation on various classification/characterization systems for sedimentary rocks in two parts,40 kmlong of the Zagros tunnel,west of *** results of extensive geotechnical explorations and field measurements were applied to obtain the rock mass classification/characterization systems such as Rock Mass Rating(RMR),Rock Condition Rating(RCR),Q-system(Q),Rock Mass Number(QN),Rock Mass index(RMi),Rock Structure Rating(RSR),and Geological Strength Index(GSI)for a wide range of sedimentary rocks.A set of systems inter-relationship is *** of these correlation relations such as RMR-Q,RMR-RMi,RMi-Q,RCR,GSI-GSI(Cai)are similar to the one or more relations proposed in the previous studies,however,some of them such as RSR-RMR,RSR-Q,RCR-QN and GSI-RMR are not similar to the previous *** set orientation and joint set number are more important parameters that cause weak correlation coefficients where both side classifications are not similar in considering them in calculating *** it is proposed to find relations between any pairs of systems that both of them consider or not consider these *** relations are proposed for a wide range of sedimentary rocks and can be applied for similar geological environments.

关键词： Rock mass dassification/characterization systems Zagros Tunnel Sedimentaiy rocks

Direct extraction of Mo(Ⅵ) from sulfate solution by synergistic extractants in the rotation column

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Chinese Journal of Chemical Engineering 2020年第2期28卷 445-455页

作者： benyamin Shakib Meisam Torab-Mostaedi Mohammad Outokesh Mehdi Asadollahzadeh Department of Energy Engineering Sharif University of TechnologyP.O.Box 11365-8639TehranIran Materials and Nuclear Fuel Research School Nuclear Science and Technology Research InstituteP.O.Box:11365-8486TehranIran

Direct extraction of molybdenum from sulfate solution with synergistic extractants(mixture of D2EHPA and TBP)was studied in the rotation *** influence of extractant concentration and initial pH of aqueous phase was studied in the bench scale *** outcomes demonstrated that the synergistic solvent extraction enhances the constancy of the extracted complexes for transfer into the organic *** the continuous experiments,the effect of different operating parameters such as speed of agitation,inlet solvent flow rate and inlet aqueous flow rate on the holdup,mean drop size,drop size distribution,slip and characteristic velocities and extraction percentage were *** correlations were proposed for prediction of hydrodynamic parameters with consideration of reaction extraction condition in the rotation ***,these correlations were compared with the experimental *** to the results,the direct extraction of Mo(Ⅵ)from aqueous solution and sulfuric media with extraction efficiency of 90.4%was obtained at higher rotor speed(240 r·min–1 rpm)in this column.

关键词： Direct extraction Molybdenum Rotation column Synergistic Extractant

A rate-based robust queue management system through multi-loop internal model controller with initial value compensation

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Journal of Control and Decision 2015年第4期2卷 257-277页

作者： Ladan khoshnevisan Farzad R.Salmasi Faculty of Engineering Electrical Engineering DepartmentUniversity of TehranTehranIran

An efficient congestion control approach should gain weighted fairness and also robustness against external ***,variations in the number of active sources cause a network to operate as a switched system in which the initial values affect the transient *** main contribution of this article is to design a rate-based adaptive robust queue management contemplating the initial value compensation(IVC).The congestion is avoided via Two-Degree-of-Freedom Internal Model Control protocol as a robust *** utilisation factors are designated according to the delay of each source(weighted fairness)in which the sources will use the maximum value of the bottleneck capacity(maximum utilisation).On the other hand,the number of the users is determined adaptively and effects of non-zero initial values are eliminated through a protocol called *** results through Network Simulator 2 and Simulink software confirm the analytical results and the efficacy of the proposed method.

关键词： adaptive robust queue management initial value compensation maximum utilisation switched system weighted fairness

Ab-Initio Study of Cobalt Impurity Effects on Phonon Spectra, Mechanical and Thermal Properties of Single Wall Carbon Nanotube （5,0）

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Chinese Physics Letters 2014年第4期31卷 110-113页

作者： H. Tashakori B. khoshnevisan F. Kanjouri Faculty of Physics University of Kashan Kashan Iran Faculty of Physics Kharazmi University Karaj Iran

We use density functional perturbation theory based on the pseudo-potential to calculate the phonon spectrum, phonon density of states, specific heat capacity and mechanical properties of pristine and cobalt doped （5,0） single wall carbon nanotube （CNT）. In the calculations, we consider one Co atom in the center of the unit cell of the tube and it is shown that the pristine （5~0） CNT is nonmagnetic while the Co-doped tube becomes magnetic. Young＇s modulus for both systems is about 1 TPa （＇after Co-doping it goes slightly higher） and the Poisson ratio for the pristine tube becomes quite a bit larger than the doped one. On the other hand, the calculated value of radial breath mode for the pristine CNT is in good agreement with the experimental reports while after Co-doping it is increased. In addition, heat capacity of the doped CNT is reduced, which leads to some important empirical applications.

关键词： CHEMICAL vapor deposition DENSITY functional theory PERTURBATION (Mathematics) CARBON nanotubes POISSON'S ratio

Integral sliding-mode robust observer-based congestion control for wireless access networks

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Journal of Control and Decision 2022年第2期9卷 152-164页

作者： Ladan khoshnevisan Farzad R.Salmasia Xinzhi Liub School of Electrical and Computer Engineering College of EngineeringUniversity of TehranTehranIran bDepartment of Applied Mathematics Faculty of MathematisUniversity of WaterlooWaterlooCanada

Designing a robust active queue management(RAQM)is mandatory to avoid congestion in networks with wireless access links,because transmission control protocol(TCP)can detect con-gestion after its occurrence in a communication network and wireless links suffer from bottleneck capacity variations caused by fading and packet error rate(PER)in the acknowledgement ***,the average window size cannot be measured explicitly from the output signal and input and state delay are imposed to a network,which complicate theRAQMdesign problem in nonlinear ***,the main contribution of this study is to design a robust observer based control procedure based on integral sliding mode protocol to estimate the average window size,to control congestion in a TCP/RAQM network and to compensate input and state ***-ulation results via professional simulator NS-2 and SIMULINK confirm that the procedure can effectively estimate the window size and can robustly avoid congestion.

关键词： Congestion control integral sliding mode robust active queue management(RAQM) robust observer-based control(ROBC) transmission control protocol(TCP) wireless access network

Invariant G^(2)V algorithm for computing SAGBI-Grobner bases

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Science China Mathematics 2013年第9期56卷 1781-1794页

作者： HASHEMI Amir M.-ALIZADEH benyamin RIAHI Monireh Department of Mathematical Sciences Isfahan University of Technology Young Researchers Club Science and Research BranchIslamic Azad University Department of Mathematics Damghan University

Faugère and Rahmany have presented the invariant F5 algorithm to compute SAGBI-Grbner bases of ideals of invariant rings. This algorithm has an incremental structure, and it is based on the matrix version of F5 algorithm to use F5 criterion to remove a part of useless reductions. Although this algorithm is more efficient than the Buchberger-like algorithm, however it does not use all the existing criteria (for an incremental structure) to detect superfluous reductions. In this paper, we consider a new algorithm, namely, invariant G2V algorithm, to compute SAGBI-Grbner bases of ideals of invariant rings using more criteria. This algorithm has a new structure and it is based on the G2V algorithm; a variant of the F5 algorithm to compute Grbner bases. We have implemented our new algorithm in Maple , and we give experimental comparison, via some examples, of performance of this algorithm with the invariant F5 algorithm.

关键词： G^(2)V algorithm invariant F5 algorithm invariant G^(2)V algorithm SAGBI-Grobner bases

Polymer interdigitated pillar electrostatic(PIPE)actuators

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Microsystems & Nanoengineering 2022年第1期8卷 185-192页

作者： Di Ni Ronald Heisser benyamin Davaji Landon Ivy Robert Shepherd Amit Lal School of Electrical and Computer Engineering Cornell UniversityIthacaNY 14853USA Sibley School of Mechanical and Aerospace Engineering Cornell UniversityIthacaNY 14853USA

This work reports a three-dimensional polymer interdigitated pillar electrostatic actuator that can produce force densities 5-10×higher than those of biological *** theory of operation,scaling,and stability is investigated using analytical and FEM *** actuator consists of two high-density arrays of interdigitated pillars that work against a restoring force generated by an integrated flexure *** actuator architecture enables linear actuation with higher displacements and pull-in free actuation to prevent the in-use stiction associated with other electrostatic *** pillars and springs are 3D printed together in the same *** pillars are coated with a gold-palladium alloy layer to form conductive *** space between the pillars is filled with liquid dielectrics for higher breakdown voltages and larger electrostatic forces due to the increase in the dielectric *** demonstrated a prototype actuator that produced a maximum work density of 54.6μJ/cc and an electrical-tomechanical energy coupling factor of 32%when actuated at 4000 *** device was operated for more than 100,000 cycles with no degradation in *** flexible polymer body was robust,allowing the actuator to operate even after high mechanical force impact,which was demonstrated by operation after drop *** it is scaled further,the reported actuator will enable soft and flexible muscle-like actuators that can be stacked in series and parallel to scale the resulting *** work paves the way for high-energy density actuators for microrobotic applications.

关键词： alloy electrostatic enable