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Petroleum Science 2013年第3期10卷 373-384页

作者： behrouz Asgarian Hamed Rahman Shokrgozar Department of Civil Engineering K. N. Toosi University of TechnologyNo. 1346 Valiasr Street Mirdamad Intersection 19967 P.O. Box. 15875-4416Tehran Iran

In this paper, the seismic response of a newly designed steel jacket offshore platform with a float over deck （FOD） system in the Persian Gulf was investigated through incremental dynamic analysis. Comparison of incremental dynamic analysis results for both directions of the platform shows that the lateral strength of the platform in the float over direction is less than its lateral strength in other direction. Dynamic characteristics measurement of a scale model of platform was also performed using forced vibration tests. From experimental measurement of the scaled model, it was observed that dynamic characteristic of the platform is different in the float over direction compared to the other direction. Therefore, a new offshore installed bracing system for the float over direction was proposed for improvement of seismic performance of this type of platform. Finally, the structure with the modified system was assessed using the probabilistic seismic assessment method as well as experimental measurement of its dynamic characteristics. It was observed that the proposed offshore installed bracing system improves the performance of platforms subjected to strong ground motion.

关键词： Steel jacket type offshore platform float-over deck mean annual frequency force vibration test seismic performance dynamic characteristics

Solvent Effects on Complexation of Molybdenum（Ⅵ） with Nitrilotriacetic Acid in Different Aqueous Solutions of Propanol

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Chinese Journal of Chemistry 2007年第3期25卷 284-288页

作者： MOHAMMADI behrouz MOHAMMADI Jalalb Chemistry Department Shahid Beheshti University Tehran Evin Iran Chemistry Department Tabriz University Tabriz Iran

By using spectrophotometric and potentiometric techniques the formation constants of the species formed in the systems H^＋＋ Mo（Ⅵ）＋nitrilotriacetic acid and H^＋＋ nitrilotriacetic acid have been determined in aqueous solutions of propanol at 25 ℃ and constant ionic strength 0.1 molodm^-3 sodium perchlorate. The composition of the complex was determined by the continuous variation method. It was shown that molybdenum（Ⅵ） forms a mononuclear 1 ： 1 complex with nitrilotriacetic acid of the type MoO3L^-3 at -lg[H^＋] =5.8. The formation constants in various media were analyzed in terms of Kamlet and Taft＇s parameters. Linear relationships were observed when lg Ks was plotted versusp. Finally, the results were discussed in terms of the effect of solvent on complexation.

关键词： solvent effect molybdenum(Ⅵ) nitrilotriacetic acid (NTA) propanol

Seismic progressive-failure analysis of tall steel structures under beam-removal scenarios

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Frontiers of Structural and Civil Engineering 2019年第4期13卷 904-917页

作者： behrouz BEHNAM Fahimeh SHOJAEI Hamid Reza RONAGH School of Civil and Environmental Engineering Amirkabir University of Technology Tehran 13496 Iran Independent Researcher Earthquake Engineer Parand 37611 Iran Centre for Infrastructure Engineering Western Sydney University NSW 2751 Australia

Investigating progressive collapse of tall structures under beam removal scenarios after earthquake is a complex subject because the earthquake damage acts as an initial condition for the subsequent scenario. An investigation is performed here on a 10 story steel moment resisting structure designed to meet the life safety level of performance when different beam removal scenarios after earthquake are considered. To this end, the structure is first subjected to the design earthquake simulated by Tabas earthquake acceleration. The beam removal scenarios are then considered at different locations assuming that both ends connections of the beam to columns are simultaneously detached from the columns;thus the removed beam falls on the underneath floor with an impact. This imposes considerable loads to the structure leading to a progressive collapse in all the scenarios considered. The results also show that the upper stories are much more vulnerable under such scenarios than the lower stories. Hence, more attention shall be paid to the beam-to-column connections of the upper stories during the process of design and construction.

关键词： progressive collapse tall steel moment-resisting frames non-linear dynamic analysis beam-removal scenario impact

Survivability evaluation for networks carrying complex traffic flows

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Digital Communications and Networks 2023年第2期9卷 534-544页

作者： Amin Jamali Mehdi Berenjkoub Hossein Saidi behrouz Shahgholi Ghahfarokhi Faculty of Computer Engineering University of IsfahanIsfahan***Iran Department of Electrical and Computer Engineering Isfahan University of TechnologyIsfahan***Iran

The capability of a system to fulfill its mission promptly in the presence of attacks,failures,or accidents is one of the qualitative definitions of *** this paper,we propose a model for survivability quantification,which is acceptable for networks carrying complex traffic *** network traffic is considered as general multi-rate,heterogeneous traffic,where the individual bandwidth demands may aggregate in complex,nonlinear *** probability is the chosen measure for survivability *** study an arbitrary topology and some other known topologies for the *** and dependent failure scenarios as well as deterministic and random traffic models are ***,we provide survivability evaluation results for different network *** results show that by using about 50%of the link capacity in networks with a relatively high number of links,the blocking probability remains near zero in the case of a limited number of failures.

关键词： Blocking probability Complex traffic Link failure Network survivability Disaster recovery Information assurance

Forced Vibration Analysis of Functionally Graded Anisotropic Nanoplates Resting on Winkler/Pasternak-Foundation

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Computers, Materials & Continua 2020年第2期62卷 607-629页

作者： behrouz Karami Maziar Janghorban Timon Rabczuk Department of Mechanical Engineering Marvdasht BranchIslamic Azad UniversityMarvdashtIran Institute of Research and Development Duy Tan UniversityDa NangViet Nam

This study investigates the forced vibration of functionally graded hexagonal nano-size plates for the first time.A quasi-three-dimensional(3D)plate theory including stretching effect is used to model the anisotropic plate as a continuum one where small-scale effects are considered based on nonlocal strain gradient ***,the plate is assumed on a Pasternak foundation in which normal and transverse shear loads are taken into *** governing equations of motion are obtained via the Hamiltonian principles which are solved using analytical based methods by means of Navier’s *** influences of the exponential factor,nonlocal parameter,strain gradient parameter,Pasternak foundation coefficients,length-to-thickness,and length-to-width ratios on the dynamic response of the nanoplates are *** addition,the accuracy of an isotropic approximate instead of the anisotropic model is *** dynamic behavior of the system shows that mechanical mathematics-based models may get better results considering the anisotropic model because the dynamic response can cause prominent differences(up to 17%)between isotropic approximation and anisotropic model.

关键词： Functionally graded materials dynamic deflection nonlocal train gradient theory Winkler-Pasternak elastic foundation

Enhancing scalability of peer-to-peer energy markets using adaptive segmentation method

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Journal of Modern Power Systems and Clean Energy 2019年第4期7卷 791-801页

作者： Mohsen KHORASANY Yateendra MISHRA behrouz BABAKI Gerard LEDWICH Department of Electrical Engineering and Computer Science Queensland University of TechnologyBrisbaneAustralia Polytechnique Montréal MontréalCanada

This paper proposes an adaptive segmentation method as a market clearing mechanism for peer-to-peer(P2P)energy trading scheme with large number of market *** the proposed method,market players participate in the market by announcing their *** the first step,players are assigned to different segments based on their features,where the balanced k-means clustering method is implemented to form *** segments are formed based on the similarity between players,where the amount of energy for trade and its corresponding price are considered as features of *** the next step,a distributed method is employed to clear the market in each segment without any need to private information of *** novelty of this paper relies on developing an adaptive algorithm for dividing large number of market players into multiple segments to enhance scalability of the P2P trading by reducing data exchange and communication *** proposed approach can be used along with any distributed method for market *** this paper,two different structures including community-based market and decentralized bilateral trading market are used to demonstrate the efficacy of the proposed *** results show the beneficial properties of the proposed segmentation method.

关键词： Energy trading Market segmentation Distributed optimization Peer-to-peer(P2P)market Alternating direction method of multipliers

Relativistic Oscillators in a Noncommutative Space and in a Magnetic Field

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Communications in Theoretical Physics 2011年第3期55卷 405-409页

作者： behrouz Mirza Rasoul Narimani Somayeh Zare Department of Physics Isfahan University of Technology Isfahan 84156-83111 Iran

In this work, we study the relativistic oscillators in a noncommutative space and in a magnetic field. It is shown that the effect of the magnetic field may compete with that of the noncommutative space and that is ab... 详细信息

关键词： noncommutative space Landau problem Kemmer oscillator

Electrochemical preparation and characterization of brain-like nanostructures of Y_2O_3

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Journal of Rare Earths 2013年第3期31卷 281-288页

作者： Mustafa Aghazadeh Mojtaba Hosseinifard Mohammad Hassan Peyrovi behrouz Sabour Department of Chemistry Islamic Azad UniversityShar-e-Ray BranchTehranIran Department of Chemistry Faculty of ScienceShahid Beheshti UniversityG.C.P.O.Box 19396-4716TehranIran

Nanostructured Y203 was successfully prepared via a two-step and template-free method. Firstly, yttrium hydroxide precursor was galvanostatically grown on the steel substrate from chloride bath by direct and pulse current deposition modes. Direct cunent deposition was carried out at the constant current density of 0.1 A/dm2 for 600 s. The pulse current was also performed at a typical on-time and off-time （ton=l S and Germ s） with an average current density of 0.05 A/dm2 （la=0.05 A/din2） for 600 s. The obtained hydroxide films were then scraped from the substrates and thermally converted into final oxide product via heat-treatment. Thermal behaviors and phase transformations during the heat treatment of the hydroxide powder samples were investigated by differential scanning calorimetry （DSC） and thermogravimetric analysis （TGA）. The final oxide products were characterized by means of X-ray diffraction （XRD）, Fourier transform infrared spectroscopy （FTIR） and scanning electron microscopy （SEM）. The results showed that the well-crystallized Y203 with brainand sphere-like morphology were achievable via pulse and direct deposition modes, respectively. It was concluded that pulse current cathodic electrodeposition offered a facile route for preparation ofnanostructured Y203.

关键词： cathodic electrodeposition heat-treatment electrochemical growth yttrium oxide brain-like nanostructure rare earths

A comparative study between friction stir processing and friction stir vibration processing to develop magnesium surface nanocomposites

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International Journal of Minerals,Metallurgy and Materials 2020年第8期27卷 1133-1146页

作者： behrouz Bagheri Mahmoud Abbasi Amin Abdollahzadeh Amir Hossein Kokabi Department of Mining and Metallurgy Amirkabir University of TechnologyTehranIran Faculty of Engineering University of KashanRavandi Blvd.KashanIran Department of Materials Science and Engineering Sharif University of TechnologyTehranIran Institute of Materials Engineering and Advanced Processes Department of Mining and MetallurgyAmirkabir University of TechnologyTehranIran

Friction stir processing(FSP)can be used to improve surface *** this study,a modified method of FSP called friction stir vibration processing(FSVP)was applied to develop a surface composite on AZ91 magnesium *** this technique,the workpiece is vibrated normal to the processing *** results illustrated that compared with the FSP method,the FSVP caused a better homogeneous distribution of SiC particles in the *** results also showed that matrix grains of friction stir vibration processed(FSV-processed)samples((26.43±2.00)μm)were finer than those of friction stir processed(FS-processed)specimens((39.43±2.00)μm).The results indicated that the ultimate tensile strength(UTS)of FSV-processed specimens(361.82 MPa)was higher than that of FS-processed specimens(324.97 MPa).The higher plastic strain in the material during FSVP,due to workpiece vibration,resulted in higher dynamic recrystallization,and consequently,finer grains were *** elongation and formability index of the FSV-processed specimen(16.88%and 6107.52 MPa·%,respectively)were higher than those of the FS-processed sample(15.24%and 4952.54 MPa·%,respectively).Moreover,the effects of FSVP were also found to intensify as the vibration frequency increased.

关键词： friction stir processing friction stir vibration processing surface composite mechanical properties microstructure

A synthesis of spirofuran-indenoquinoxalines via isocyanid-based one-pot four-component reaction

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Chinese Chemical Letters 2016年第7期27卷 1040-1043页

作者： Nahid Sabouri Gholam Hossein Mahdavinia behrouz Notash Department of Chemistry Marvdasht Branch Islamic Azad University Department of Chemistry Shahid Beheshti University

A simple and versatile procedure for the combinatorial synthesis of（Z）-dialkyl-5-（alkylimino）-5Hspiro[furan-2,ll’-indeno[l,2-b]quinoxaline]-3,4-dicarboxylates via the catalyst-free one-pot fourcomponent reaction ... 详细信息

关键词： One-pot Multicomponent Catalyst free Spirofuranindenoquinoxalines Isocyanide