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Journal of marine Science and Application 2016年第4期15卷 463-477页

作者： S.m.Zadeh D.m.WPowers K.Sammut a.m.yazdani Centre for maritime Engineering Control and Imaging School of Computer Science Engineering and Mathematics Flinders University Adelaide SA 5042 Australia

Autonomous Underwater Vehicles （AUVs） are capable of conducting various underwater missions and marine tasks over long periods of time. In this study, a novel conflict-free motion-planning framework is introduced. This framework enhances AUV mission performance by completing the maximum number of highest priority tasks in a limited time through a large-scale waypoint cluttered operating field and ensuring safe deployment during the mission. The proposed combinatorial route-path-planner model takes advantage of the Biogeography- Based Optimization （BBO） algorithm to satisfy the objectives of both higher- and lower-level motion planners and guarantee the maximization of mission productivity for a single vehicle operation. The performance of the model is investigated under different scenarios, including cost constraints in time-varying operating fields. To demonstrate the reliability of the proposed model, the performance of each motion planner is separately assessed and statistical analysis is conducted to evaluate the total performance of the entire model. The simulation results indicate the stability of the proposed model and the feasibility of its application to real-time experiments.

关键词： autonomous underwater vehicles underwater missions route planning biogeography-based optimization computational intelligence

Efficient AUV Path Planning in Time-Variant Underwater Environment Using Differential Evolution Algorithm

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Journal of marine Science and Application 2018年第4期17卷 585-591页

作者： S.mahmoud Zadeh D.m.W Powers a.m.yazdani K.Sammut A.Atyabi School of Computer Science Engineering and Mathematics Flinders University Tonsley Centre for maritime Engineering Control and Imaging Flinders University Seattle Children's Research Institute University of Washington

Robust and efficient AUV path planning is a key element for persistence AUV maneuvering in variable underwater environments. To develop such a path planning system, in this study, differential evolution(DE) algorithm is employed. The performance of the DE-based planner in generating time-efficient paths to direct the AUV from its initial conditions to the target of interest is investigated within a complexed 3D underwater environment incorporated with turbulent current vector fields, coastal area,islands, and static/dynamic obstacles. The results of simulations indicate the inherent efficiency of the DE-based path planner as it is capable of extracting feasible areas of a real map to determine the allowed spaces for the vehicle deployment while coping undesired current disturbances, exploiting desirable currents, and avoiding collision boundaries in directing the vehicle to its destination. The results are implementable for a realistic scenario and on-board real AUV as the DE planner satisfies all vehicular and environmental constraints while minimizing the travel time/distance, in a computationally efficient manner.

关键词： Path planning Differential evolution Autonomous underwater vehicles Evolutionary algorithms Obstacle avoidance

Synergistic effect of seawater's parameters on the corrosion rate of the austenitic stainless steel 304

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Acta metallurgica Sinica(English Letters) 2010年第3期23卷 161-170页

作者： S.Atashin m.Pakshir A.yazdani Department of materials Science and Engineering Shiraz University

In this article the corrosion rate of the austenitic stainless steel type 304, under the synergistic effect of environmental factors has been assessed via potentiodynamic polarization ***, velocity, pH and temperature are the factors which induce effects on the corrosion rate of the considered *** analysis is applied using the full two-level factorial experimental design method, which results in the contribution value of each parameter in changing the quantity of average corrosion rate in both individual and synergistic *** this quantitative analysis, qualitative analysis has been used to predict the variation *** two analyses show the important role of the synergistic action, which changes the variation direction of corrosion rate and the contribution percentage of each parameter in varying the value of corrosion *** both these analyses can show the magnitude and quality of each parameter＇s effect, which is remarkably valuable in marine applications.

关键词： Stainless steel 304 Environmental parameters Seawater corrosion Synergistic effect

Interaction between B-Doped C60 Fullerene and Glycine Amino Acid from First-Principles Simulation

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Chinese Physics Letters 2010年第4期27卷 83-86页

作者： m. D. Ganji H. yazdani Department of Chemistry Islamic Azad University Ghaemshahr branch Mazandaran Iran

The possibility of formation of complexes between glycine and boron doped C60 （C59B） fullerene is investigated and compared with that of C60 fullerene by using the density functional theory calculations. It has been found that the binding of glycine to C59B generated the most stable complexes via its carbonyl oxygen active site, with a binding energy of-37.89 kcal/mol, while the glycine molecule prefers to bind to the pure C60 cage via its amino nitrogen active site, consistent with the recent experimental and theoretical studies. We have also tested the stability of the most stable Gly-C59B complex with ab initio molecular dynamics simulation, carried out at room temperature. These indicate that the B-doped C60 fullerenes seem to be more suitable materials for bindings to proteins than pure C60 fullerenes.

关键词： Surfaces interfaces and thin films Biological physics Condensed matter: structural mechanical & thermal Chemical physics and physical chemistry

The Energy Distribution of a Noncommutative Reissner–Nordström Black Hole

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Chinese Physics Letters 2013年第9期30卷 25-28页

作者： Kourosh Nozari A.yazdani Center for Excellence in Astronomy and Astrophysics(CEAAI-RIAAm)-maragha P.O.Box55134-441MaraghaIran Department of Physics Faculty of Basic SciencesUniversity of MazandaranP.O.Box 47416-95447BabolsarIran

We study the energy distribution of a noncommutative Reissner–Nordström black *** consider both Ein-stein and møller prescriptions,and compare our results with the corresponding results obtained recently for a Schwar... 详细信息

关键词： Reissner commutative black

Effect of sub-zero cooling on microstructure and mechanical properties of a low alloyed austempered ductile iron

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China Foundry 2007年第2期4卷 120-123页

作者： S. yazdani m. Ardestani Faculty of materials Engineering Sahand University of TechnologyTabrizIRAN

The effect of sub-zero cooling on microstructure and mechanical properties of a low alloyed austempered ductile iron has been investigated. Austempering of samples was performed at 325℃and 400℃after austenitizing at 875℃and 950℃. The sub-zero treatments were carried out by cooling down the samples to -30℃, -70℃and -196℃. The changes in volume fraction of austenite and mechanical properties were determined after cooling to each temperature. The austenite volume fraction of samples which were austenitized at 875℃and austempered at 325℃remained unchanged, whilst it reduced in samples austenitized at 950℃and 875℃for austempering temperature of 400℃. In these specimens, some austenite transformed to martensite after subzero cooling. mechanical property measurements showed a slight increase in strength and hardness and decrease in elongation and toughness due to this transformation behavior.

关键词： austempered ductile iron austenite sub-zero cooling martensitic transformation ausferrite

Smart component monitoring system increases the efficiency of photovoltaic plants

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Clean Energy 2023年第2期7卷 I0001-I0009,312页

作者： Hassan yazdani mehdi Radmehr Alireza Ghorbani Department of Electrical Engineering Sari BranchIslamic Azad UniversitySariIran

Due to the increasing expansion of renewable energy,especially the widespread installation of solar power plants worldwide,to better exploit and increase the efficiency and quality of power generation,we need to closely monitor the performance of important components of the *** this study,using an innovative smart monitoring system and electronic sensors,we monitored compo-nents such as power in photovoltaic(PV)arrays in real time,including the phenomenon of hot spots as an example of power loss in PV *** of hot spots is very difficult to deal with in a large power *** results also demonstrated smart monitoring that increased detection speed and increased the efficiency rate per supervisory technician by≤36% compared with the previous ef-ficiency rate,which was 10% per technical staff,and increased the quality of the operation of each solar power *** this paper,meteorological data were coordinated with research data to validate the ***,to compare the results of using the smart monitoring method with the conventional observation method,a complete diagram of a 5-kW solar system in mATLAB■2018 was simulated and output diagrams were ***,to provide a comprehensive validation,our research results were com-pared with technical data obtained from a local 5-kW solar power plant located in Sari,Iran(36°33ʹ48″N,53°03ʹ36″E)with an average annual irradiation of 1490 kWh/m^(2).When the simulation results and research are analysed,it is clear that the smart and real-time monitoring approach brings various benefits to solar power plants.

关键词： photovoltaic power plant online monitoring efficiency solar cell power PV modules

Dry sliding wear of Ni alloyed austempered ductile iron

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China Foundry 2016年第5期13卷 361-367页

作者： E.Akbarzadeh Chiniforush m.A.Rahimi S.yazdani Faculty of materials Engineering Sahand University of Technology

measurements of dry sliding wear are presented for ductile irons with composition Fe-3.56C-2.67Si- 0.25mo-0.5Cu and Ni contents of 0.8 and 1.5 in wt.% with applied loads of 50, 100 and 150 N for austempering temperatures of 270, 320, and 370 ℃ after austenitizing at 870 ℃ for 120 min. The mechanical property measurements show that the grades of the ASTm 897m： 1990 Standard can be satisfied for the selected austempering conditions. The results show that wear resistance is independent of austempedng temperature with an applied load of 50 N, but there is a strong dependence at higher austempering temperatures with applied loads of 100 and 150 N. Observations indicate that wear is due to subsurface fatigue with cracks nucleated at deformed graphite nodules.

关键词： austempered ductile iron wear austenite ausferrite nickel

An Investigation on Rotating Bending Fatigue Behavior of Nanostructured Low-Temperature Bainitic Steel

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Acta metallurgica Sinica(English Letters) 2014年第2期27卷 233-238页

作者： B.R.Shendy m.N.Yoozbashi B.Avishan S.yazdani Faculty of materials Engineering Sahand University of Technology University of Applied Science and Technology Faculty of Engineering Azarbaijan Shahid Madani University

The aim of this work is to investigate the fatigue behavior of a new class of nanostructured, low-temperature bainitic steels, where rotating bending fatigue tests were conducted on samples isothermally transformed at 300, 250, and 200 ℃, after which, fracture surfaces were examined using scanning electron microscopy. Results showed that, fatigue limits of about 820, 945, and 1,005 mPa were achieved for the samples transformed at each transformation temperature, respectively. moreover, according to the SEm micrographs, secondary crack initiation was observed in the high carbon retained austenite blocks for samples transformed at 300 ℃ and at the interface of blocky austenite-bainitic ferrite for samples transformed at 250 and 200 ℃.

关键词： Fatigue Bainitic ferrite Retained austenite Fractography

Recent progress on in situ characterizations of electrochemically intercalated transition metal dichalcogenides

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Nano Research 2019年第9期12卷 2126-2139页

作者： Sajad yazdani milad Yarali Judy J. Cha Department of mechanical Engineering and materials Science Yale UniversityNew HavenCT 06511USA Energy Sciences Institute Yale University West CampusWest HavenCT 06516USA

Layered transition metal dichalcogenides(TmDCs)have been extensively studied owing to their unique physical and chemical *** van der Waals(vdW)interact!ons betwee n the stacki ng layers of TmDCs allow intercalati on of various species including mono vale nt alkali,divale nt alkaline earth and multivale nt metal ions,zero-vale nt transiti on metals,as well as orga nic molecules,all of which can drastically alter fun dame ntal properties of the *** urge to understa nd the phe nomena and the desire to exploit them for applicati ons have inspired a great deal of investigations.A large portion of the mystery has been unveiled over the past decade of intense research;however,many questions remain open and require further *** review is concerned with investigations on structural and electronic evolution of TmDCs drive n by electrochemically con trolled in tercalati ***,we aim to survey the rece nt adva nces and experime ntal platforms for mon itoring the in tercalati on processes in situ by utilizi ng nano *** additi on,several in quiries and prospects are outlined in a broader con text for future ave nues of studies.

关键词： transition metal dichalcogenides electrochemical intercalation in situ characterizations transmission electron microscopy(TEm) magnetotransport measurements