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Optimal PD/PID control of smart base isolated buildings equipped with piezoelectric friction dampers

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Earthquake Engineering and Engineering Vibration 2013年第1期12卷 39-54页

作者： sadegh etedali Mohammad Reza Sohrabi Saeed Tavakoli .Department of Civil Engineering Faculty of EngineeringUniversity of Sistan and Baluchestan Department of Civil Engineering Faculty of EngineeringUniversity of Sistan and Baluchestan Faculty of Electrical and Computer Engineering University of Sistan and Baluchestan

Long-period pulses in near-field earthquakes lead to large displacements in the base of isolated *** dissipate energy in isolated structures using semi-active control,piezoelectric friction dampers（PFD） can be *** performance of a PFD is highly dependent on the strategy applied to adjust its contact *** this paper,the seismic control of a benchmark isolated building equipped with PFD using PD/PID controllers is *** genetic algorithms,these controllers are optimized to create a balance between the performance and robustness of the closed-loop structural *** advantage of this technique is that the controller forces can easily be *** addition,the structure is equipped with only a single sensor at the base floor to measure the base *** seven pairs of earthquakes and nine performance indices,the performance of the closed-loop system is ***,the results are compared with those given by two well-known methods：the maximum possive operation of piezoelectric friction dampers and LQG *** simulation results show that the proposed controllers perform better than the others in terms of simultaneous reduction of floor acceleration and maximum displacement of the ***,they are able to reduce the displacement of the isolator systems for different earthquakes without losing the advantages of isolation.

关键词： seismic isolation semi-active control piezoelectric friction dampers PD/PID controllers

A hybrid LQR-PID control design for seismic control of buildings equipped with ATMD

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Frontiers of Structural and Civil Engineering 2018年第1期12卷 44-57页

作者： Amir Hossein HEIDARI sadegh etedali Mohamad Reza JAVAHERI-TAFTI Department of Civil Engineering Taft Branch Islamic Azad University Taft Iran Department of Civil Engineering Birjand University of Technology P.O. Box 97175-569 Birjand Iran

This paper presents an efficient hybrid control approach through combining the idea of proportional- integral-derivative （PID） controller and linear quadratic regulator （LQR） control algorithm. The proposed LQR-PID controller, while having the advantage of the classical PID controller, is easy to implement in seismic-excited structures. Using an optimization procedure based on a cuckoo search （CS） algorithm, the LQR-PID controller is designed for a seismic- excited structure equipped with an active tuned mass damper （ATMD）. Considering four earthquakes, the performance of the proposed LQR-PID controller is evaluated. Then, the results are compared with those given by a LQR controller. The simulation results indicate that the LQR-PID performs better than the LQR controller in reduction of seismic responses of the structure in the terms of displacement and acceleration of stories of the structure.

关键词： eismic control tuned mass dampers cuckoo search PID controller LQR controller

Future meteorological drought conditions in southwestern Iran based on the NEX-GDDP climate dataset

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Journal of Arid Land 2023年第4期15卷 377-392页

作者： Sakine KOOHI Hadi RAMEZANI etedali Department of Water Engineering Faculty of Agriculture and Natural ResourcesImam Khomeini International UniversityQazvin 96818Iran

Investigation of the climate change effects on drought is required to develop management strategies for minimizing adverse social and economic ***,studying the future meteorological drought conditions at a local scale is *** this study,we assessed the efficiency of seven downscaled Global Climate Models(GCMs)provided by the NASA Earth Exchange Global Daily Downscaled Projections(NEX-GDDP),and investigated the impacts of climate change on future meteorological drought using Standard Precipitation Index(SPI)in the Karoun River Basin(KRB)of southwestern Iran under two Representative Concentration Pathway(RCP)emission scenarios,i.e.,RCP4.5 and *** results demonstrated that SPI estimated based on the Meteorological Research Institute Coupled Global Climate Model version 3(MRI-CGCM3)is consistent with the one estimated by synoptic stations during the historical period(1990-2005).The root mean square error(RMSE)value is less than 0.75 in 77%of the synoptic *** have high uncertainty in most synoptic stations except those located in the *** the average of a few GCMs to improve performance and reduce uncertainty is suggested by the *** results revealed that with the areas affected by wetness decreasing in the KRB,drought frequency in the North KRB is likely to increase at the end of the 21st century under RCP4.5 and RCP8.5 *** the seasonal scale,the decreasing trend for SPI in spring,summer,and winter shows a drought tendency in this *** climate-induced drought hazard can have vast consequences,especially in agriculture and rural ***,an increasing trend in drought during the growing seasons under RCP scenarios is vital for water managers and farmers to adopt strategies to reduce the *** results of this study are of great value for formulating sustainable water resources management plans affected by climate change.

关键词： climate change meteorological drought Global Climate Models(GCMs) Standard Precipitation Index(SPI) Representative Concentration Pathway(RCP) NASA Earth Exchange Global Daily Downscaled Projections(NEX-GDDP) southwestern Iran

Spatiotemporal variations of evapotranspiration and reference crop water requirement over 1957-2016 in Iran based on CRU TS gridded dataset

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Journal of Arid Land 2021年第8期13卷 858-878页

作者： Brian COLLINS Hadi RAMEZANI etedali Ameneh TAVAKOL Abbas KAVIANI College of Science and Engineering James Cook UniversityTownsvilleQLD 4811Australia Department of Water Sciences and Engineering Imam Khomeini International UniversityQazvin 34148Iran Biological and Agricultural Engineering Kansas State UniversityManhattanKS 66506USA

Agriculture needs to produce more food to feed the growing population in the 21st *** makes the reference crop water requirement(WREQ)a major challenge especially in regions with limited water and high water ***,with large climatic variability,is experiencing a serious water crisis due to limited water resources and inefficient *** order to overcome the issue of uneven distribution of weather stations,gridded Climatic Research Unit(CRU)data was applied to analyze the changes in potential evapotranspiration(PET),effective precipitation(EFFPRE)and *** of data using in situ observation showed an acceptable performance of CRU in *** in PET,EFFPRE and WREQ were analyzed in two 30-a periods 1957-1986 and *** two periods showed an increase in PET and WREQ in regions extended from the southwest to northeast and a decrease in the southeast,more significant in summer and ***,EFFPRE decreased in the southeast,northeast,and northwest,especially in winter and *** of annual trends revealed an upward trend in PET(14.32 mm/decade)and WREQ(25.50 mm/decade),but a downward trend in EFFPRE(-11.8 mm/decade)over the second *** in PET,EFFPRE and WREQ in winter have the impact on the annual *** climate variables,WREQ showed a significant correlation(r=0.59)with minimum *** increase in WREQ and decrease in EFFPRE would exacerbate the agricultural water crisis in *** all changes in PET and WREQ,immediate actions are needed to address the challenges in agriculture and adapt to the changing climate.

关键词： evapotranspiration reference crop water requirement effective precipitation trend Iran spatiotemporal change CRU TS data

Evaluation of CRU TS, GPCC, AgMERRA, and AgCFSR meteorological datasets for estimating climate and crop variables: A case study of maize in Qazvin Province, Iran

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Journal of Arid Land 2022年第12期14卷 1361-1376页

作者： Faraz GORGIN PAVEH Hadi RAMEZANI etedali Brian COLLINS Syracuse University Syracuse 13244USA Imam Khomeini International University Qazvin 34149-16818Iran Centre for Crop Science The University of QueenslandBrisbane 4072Australia

In the past few decades,meteorological datasets from remote sensing techniques in agricultural and water resources management have been used by various researchers and *** on the literature,meteorological datasets are not more accurate than synoptic stations,but their various advantages,such as spatial coverage,time coverage,accessibility,and free use,have made these techniques superior,and sometimes we can use them instead of synoptic *** this study,we used four meteorological datasets,including Climatic Research Unit gridded Time Series(CRU TS),Global Precipitation Climatology Centre(GPCC),Agricultural National Aeronautics and Space Administration Modern-Era Retrospective Analysis for Research and Applications(AgMERRA),Agricultural Climate Forecast System Reanalysis(AgCFSR),to estimate climate variables,i.e.,precipitation,maximum temperature,and minimum temperature,and crop variables,i.e.,reference evapotranspiration,irrigation requirement,biomass,and yield of maize,in Qazvin Province of Iran during *** first,data were gathered from the four meteorological datasets and synoptic station in this province,and climate variables were ***,after using the AquaCrop model to calculate the crop variables,we compared the results of the synoptic station and meteorological *** the four meteorological datasets showed strong performance for estimating climate *** and AgCFSR had more accurate estimations for precipitation and maximum ***,their normalized root mean square error was inferior to CRU for minimum ***,they were all very efficient for estimating the biomass and yield of maize in this *** reference evapotranspiration and irrigation requirement CRU TS and GPCC were the most efficient rather than AgMERRA and *** for the estimation of biomass and yield,all the four meteorological datasets were *** sum up,GPCC and AgCFSR were the two best datasets in thi

关键词： climate variables crop variables meteorological datasets precipitation reference evapotranspiration irrigation requirement Iran

Effect of carbon nanotube on physical and mechanical properties of natural fiber/glass fiber/cement composites

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Journal of Forestry Research 2015年第1期26卷 247-251页

作者： Hamed Younesi Kordkheili Shokouh etedali Shehni Ghorban Niyatzade School of Wood and Paper Science and Technology Maziyar University Department of Wood and Paper Science Faculty of Natural ResourcesTarbiat Modares University Department of Chemistry Payam Noor University

The objective of this investigation was to introduce a cement-based composite of higher quality. For this purpose new hybrid nanocomposite from bagasse fiber,glass fiber and multi-wall carbon nanotubes（MWCNTs）were manufactured. The physical and mechanical properties of the manufactured composites were measured according to standard methods. The properties of the manufactured hybrid nanocomposites were dramatically better than traditional composites. Also all the reinforced composites with carbon nanotube, glass fiber or bagasse fiber exhibited better properties rather than neat *** results indicated that bagasse fiber proved suitable for substitution of glass fiber as a reinforcing agent in the cement composites. The hybrid nanocomposite containing10 % glass fiber, 10 % bagasse fiber and 1.5 % MWCNTs was selected as the best compound.

关键词： Cement hybrid nanocomposites Multi-wall carbon nanotubes Bagasse fiber Physical and mechanical properties