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A novel semi-active TMD with folding variable stiffness spring

Earthquake Engineering and Engineering Vibration 2014年第3期13卷 509-518页

作者： M.H.Rafi eipour a.k.ghorbani-tanha M.Rahimian R.Mohammadi-Ghazi Department of Civil Engineering Science and Research Branch Islamic Azad University Tehran 39187-97717 Iran School of Civil Engineering College of Engineering University of Tehran P.O.Box 11155-4563 Tehran Iran Department of Civil and Environmental Engineering Massachusetts Institute of Technology Cambridge MA USA Formerly with School of Civil Engineering College of Engineering University of Tehran P.O.Box 11155-4563 Tehran Iran

An innovative variable stiffness device is proposed and investigated based on numerical simulations. The device, called a folding variable stiffness spring （FVSS）, can be widely used, especially in tuned mass dampers （TMDs） with adaptive stiffness. An important characteristic of FVSS is its capability to change the stiffness between lower and upper bounds through a small change of distance between its supports. This special feature results in lower time-lag errors and readjustment in shorter time intervals. The governing equations of the device are derived and simplified for a symmetrical FVSS with similar elements. This device is then used to control a single-degree-of-freedom （SDOF） structure as well as a multi-degree-of-freedom （MDOF） structure via a semi-active TMD. Numerical simulations are conducted to compare several control cases for these structures. To make it more realistic, a real direct current motor with its own limitations is simulated in addition to an ideal control case with no limitations and both the results are compared. It is shown that the proposed device can be effectively used to suppress undesirable vibrations of a structure and considerably improves the performance of the controller compared to a passive device.

关键词： semi-active tuned mass damper variable stiffness folding variable stiffness spring

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Predicting density log from well log using machine learning techniques and heuristic optimization algorithm:A comparative study

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Petroleum Research 2024年第2期9卷 176-192页

作者： Mehdi Rahmati Ghasem Zargar Abbas Ayatizadeh tanha National Iranian Drilling Company Well Logging DepartmentAhwazIran Faculty Member of Petroleum University of Technology Iran Department of Petroleum Engineering Tarbiat Modares UniversityTehranIran

In the petroleum industry,the analysis of petrophysical parameters is critical for efficient reservoir management,production optimization,development strategies,and accurate hydrocarbon reserve *** recent years,the integration of machine learning methodologies has revolutionized the field,addressing challenges in geology,geophysics,and petroleum engineering,even when confronted with limited or imperfect *** study focuses on the prediction of density logs,a pivotal factor in evaluating reservoir hydrocarbon *** is important to note that during well logging operations,log data for specific depths of interest may be missing or incorrect,presenting a significant *** tackle this issue,we employed the Adaptive Neuro-Fuzzy Inference System(ANFIS)and Artificial Neural Networks(ANN)in combination with advanced optimization algorithms,including Particle Swarm Optimization(PSO),Imperialist Competitive Algorithms(ICA),and Genetic Algorithms(GA).These methods exhibit promising performance in predicting density logs from gamma-ray,neutron,sonic,and photoelectric log ***,our results highlight that the Genetic Algorithms-based Artificial Neural Network(GA-ANN)approach outperforms all other methods,achieving an impressive Mean Squared Error(MSE)of *** comparison,ANFIS records an MSE of 0.0015,ICA-ANN 0.0090,PSO-ANN 0.0093,and ANN 0.0183.

关键词： Density log Machine learning approaches Artificial neural networks(ANN) Adaptive neuro-fuzzy inference system(ANFIS) Optimization algorithm

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Annual growth of Fagus orientalis is limited by spring drought conditions in Iran’s Golestan Province

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Journal of Forestry Research 2024年第1期35卷 128-142页

作者： khalil ghorbani Jahangir Mohammadi Laleh Rezaei Ghaleh Department of Water Engineering Faculty of Water and Soil EngineeringGorgan University of Agricultural Sciences and Natural ResourcesGorganIran Department of Forestry Gorgan University of Agricultural Sciences and Natural ResourcesGorganIran Department of Water Engineering Faculty of AgricultureUrmia UniversityUrmiaIran

Due to the lack of a uniform and accurate defi-nition of‘drought’,several indicators have been introduced based on different variables and methods,and the efficiency of each of these is determined according to their relationship with *** relationship between two drought indices,SPI(standardized precipitation index)and SPEI(standard-ized precipitation-evapotranspiration index)in different sea-sons was investigated using annual rings of 15 tree samples to determine the effect of drought on the growth of oriental beech(Fagus orientalis Lipsky)in the Hyrcanian forests of northern *** different evapotranspiration calcula-tion methods were evaluated on SPEI efficiency based on Hargreaves-Samani,Thornthwaite,and Penman-Monteith methods using the step-by-step M5 decision tree regression *** results show that SPEI based on the Penman-Monteith in a three-month time scale(spring)had similar temporal changes and a better relationship with annual tree rings(R^(2)=0.81)at a 0.05 significant *** change and a decreasing trend in the time series of annual tree rings are similar to the variation in the SPEI based on the Penman-Monteith *** affecting evapotranspiration,temperature,wind speed,and sunshine hours(used in the Penman-Monteith method),increased but precipitation *** non-linear modeling methods,SPEI based on Penman-Monteith best illustrated climate changes affecting tree growth.

关键词： Climate change Drought index Hyrcanian forests SPEI'Annual growth rings Fagus orientalis

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Modelling rapid non-destructive test using light weight deflectometer on granular soils across different degrees of saturation

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第7期16卷 2732-2748页

作者： Javad ghorbani Arooran Sounthararajah Troyee Tanu Dutta Jayantha kodikara ARC Smart Pavements Hub Dept.of Civil EngineeringMonash UniversityVIC3800Australia

This study introduces an advanced finite element model for the light weight deflectometer(LWD),which integrates contact mechanics with fully coupled *** simulating LWD tests on granular soils at various saturation levels,the model accurately reflects the dependence of the LWD modulus on dry density,water content,and effective *** model addresses and overcomes the limitations of previous finite element models for this specific ***,this research presents the first experimentally validated fully coupled contact impact ***,the research provides a comparative assessment of elastoplastic and nonlinear elastic models and contrasts an enriched node-tosegment method(developed in this study)with the more precise mortar technique for contact *** comparisons reveal unique advantages and challenges for each ***,the study underscores the importance of careful application of the LWD modulus,emphasising the need for sophisticated tools to interpret soil behaviour accurately.

关键词： Granular soils Plasticity Finite element analysis Contact mechanics Modulus Degree of saturation

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Targeted anti-tumor synergistic effects of Myc decoy oligodeoxynucleotides-loaded selenium nanostructure combined with chemoradiotherapy on LNCaP prostate cancer cells

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Oncology Research 2024年第1期32卷 101-125页

作者： ROGHAYEH ghorbani MAHMOUD GHARBAVI ALI SHARAFI ELHAM RISMANI HAMED REZAEEJAM YOUSEF MORTAZAVI BEHROOZ JOHARI Department of Medical Biotechnology School of MedicineZanjan University of Medical SciencesZanjanIran Nanotechnology Research Center Ahvaz Jundishapur University of Medical SciencesAhvazIran Zanjan Pharmaceutical Biotechnology Research Center Zanjan University of Medical SciencesZanjanIran Department of Pharmaceutical Biotechnology School of PharmacyZanjan University of Medical SciencesZanjanIran Molecular Medicine Department Biotechnology Research CenterPasteur Institute of IranPasteur AvenueTehranIran Department of Radiology Technology School of Allied Medical SciencesZanjan University of Medical SciencesZanjanIran

In the present study,we investigated the synergistic effects of targeted methotrexate-selenium nanostructure containing Myc decoy oligodeoxynucleotides along with X-irradiation exposure as a combination therapy on LNCaP prostate cancer *** decoy ODNs were designed based on the promoter of Bcl-2 gene and analyzed by molecular docking and molecular dynamics *** were loaded on the synthesized Se@BSA@Chi-MTX *** physicochemical characteristics of nanostructures were determined by FTIR,DLS,UV-vis,TEM,EDX,in vitro release,and hemolysis ***,the cytotoxicity properties of them with and without X-irradiation were investigated by uptake,MTT,cell cycle,apoptosis,and scratch assays on the LNCaP cell *** results of DLS and TEM showed negative charge(−9 mV)and nanometer size(40 nm)for Se@BSA@Chi-DEC-MTX NPs,*** results of FTIR,UV-vis,and EDX showed the proper interaction of different parts and the correct synthesis of *** results of hemolysis showed the hemocompatibility of this nanoparticle in concentrations less than 6 mg/*** ODNs release from the nanostructures showed a pH-dependent manner,and the release rate was 15%higher in acidic *** targeted Se@BSA@Chi-labeled ODN-MTX NPs were efficiently taken up by LNCaP cells by targeting the prostate-specific membrane antigen(PSMA).The significant synergistic effects of nanostructure(containing MTX drug)treatment along with X-irradiation showed cell growth inhibition,apoptosis induction(~57%),cell cycle arrest(G2/M phase),and migration inhibition(up to 90%)compared to the *** results suggested that the Se@BSA@Chi-DEC-MTX NPs can potentially suppress the cell growth of LNCaP *** nanostructure system can be a promising approach for targeted drug delivery and chemoradiotherapy in prostate cancer treatment.

关键词： Chemoradiotherapy Combination therapy Decoy oligodeoxynucleotides Myc transcription factor Selenium nanoparticle Prostate cancer

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Event segmentation in ADHD:neglect of social information and deviant theta activity point to a mechanism underlying ADHD

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General Psychiatry 2024年第3期37卷 431-439页

作者： Astrid Prochnow Xianzhen Zhou Foroogh ghorbani Veit Roessner Bernhard Hommel Christian Beste Cognitive Neurophysiology Department of Child and Adolescent PsychiatryFaculty of MedicineTU DresdenDresdenGermany Faculty of Psychology Shandong Normal UniversityJinanShandongChina

Background Attention-deficit/hyperactivity disorder(ADHD)is one of the most frequently diagnosed psychiatric conditions in children and *** the symptoms appear to be well described,no coherent conceptual mechanistic framework integrates their occurrence and variance and the associated problems that people with ADHD *** The current study proposes that altered event segmentation processes provide a novel mechanistic framework for understanding deficits in *** Adolescents with ADHD and neurotypically developing(NT)peers watched a short movie and were then asked to indicate the boundaries between meaningful segments of the *** recorded electroencephalography(EEG)data were analysed for differences in frequency band activity and effective connectivity between brain *** Compared with their NT peers,the ADHD group showed less dependence of their segmentation behaviour on social information,indicating that they did not consider social information to the same extent as their unaffected *** divergence was accompanied by differences in EEG theta band activity and a different effective connectivity network architecture at the source ***,NT adolescents primarily showed error signalling in and between the left and right fusiform gyri related to social information processing,which was not the case in the ADHD *** the ADHD group,the inferior frontal cortex associated with attentional sampling served as a hub instead,indicating problems in the deployment of attentional *** This study shows that adolescents with ADHD perceive events differently from their NT peers,in association with a different brain network architecture that reflects less adaptation to the situation and problems in attentional sampling of environmental *** results call for a novel conceptual view of ADHD,based on event segmentation theory.

关键词： instead meaningful primarily

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Semi-active fuzzy control of Lali Cable-Stayed Bridge using MR dampers under seismic excitation

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Frontiers of Structural and Civil Engineering 2020年第3期14卷 706-721页

作者： Sajad JAVADINASAB HORMOZABAD Amir k ghorbani-tanha School of Civil Engineering College of EngineeringUniversity of TehranTehran 11155-4563Iran

Seismic control of cable-stayed bridges is of paramount importance due to their complex dynamic behavior,high flexibility,and low structural *** the present study,several semi-active Fuzzy Control Algorithms(FCAs)for vibration mitigation of Lali Cable-Stayed Bridge are *** demonstrate the efficiency of the algorithms,a comprehensive nonlinear 3-D model of the bridge is created using *** efficient method for connecting MATLAB and OpenSees is devised for applying FCAs to the structural model of the *** innovative fuzzy rulebases are introduced.A total of six different fiuzzy rule-bases are *** efficiency of the FCAs is evaluated in a comparative *** performance of fuzzy control systems is also compared with a sky-hook and a passive-on ***,the sensitivity of efficiency of control systems to the peak ground acceleration is evaluated *** addition,the effect of time lag is also *** study thoroughly examines the efficiency of the FCAs in different ***,the results can be regarded as a general guide to design semi-active fuzzy control systems for vibration mitigation of cable-stayed bridges.

关键词： semi-active control Fuzzy Control Algorithm cable-stayed bridge MR damper Lali Bridge

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Closure to“Discussion on‘Optimum placement and characteristics of velocity-dependent dampers under seismic excitation' by SA Mousavi and Ak ghorbani-tanha”by Izuru Takewaki

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Earthquake Engineering and Engineering Vibration 2013年第4期12卷 681-682页

作者： Seyed Amin Mousavi Amir k.ghorbani-tanha School of Civil Engineering College of EngineeringUniversity of Tehran

The authors would like to thank the discusser for his considerations and comments. The discusser believes that some of the derived formulations need to be referred to his previously published works and also some relat... 详细信息

关键词： Optimum placement and characteristics of velocity-dependent dampers under seismic excitation by SA Mousavi and Ak ghorbani-tanha Closure to

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Exploring the relationship between ambient sulfur dioxide and semen quality parameters:A systematic review and meta-analysis

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Asian pacific Journal of Reproduction 2024年第1期13卷 12-21页

作者： Seyed Sobhan Bahreiny Mojtaba Aghaei Mohammad Reza Dabbagh Hamid ghorbani Moslem Javidan Reza Mohammadpour Fard Student Research Committee Ahvaz Jundishapur University of Medical SciencesAhvazIran Medical Basic Sciences Research Institute Physiology Research CenterDepartment of PhysiologySchool of MedicineAhvaz Jundishapur University of Medical SciencesAhvazIran Department of Biology Faculty of ScienceShahid Chamran University of AhvazAhvazIran Department of Immunology Faculty of MedicineAhvaz Jundishapur University of Medical SciencesAhvazIran

Objective:To investigate the relationship between ambient sulfur dioxide(SO2)exposure and semen quality ***:A systematic literature search was conducted to identify relevant studies investigating the association between SO2 exposure and semen quality *** search encompassed the timeframe from January 2000 to May 2023 and included electronic databases such as Web of Science,Google Scholar,PubMed,Cochrane,and *** effect estimates with 95%confidence intervals(CI)were calculated using percent changes(PC).The meta-analysis included seven studies with 6711 participants and 15087 semen ***:The results revealed a significant negative association between ambient SO2 exposure and certain semen quality *** particular,SO2 exposure was associated with a significant decrease in progressive motility(PC=0.032;95%CI:-0.063 to-0.001;P=0.044)and sperm concentration(PC=-0.020;95%CI:-0.036 to-0.005;P=0.012).However,no statistically significant associations were observed for total sperm count(PC=-0.038;95%CI:-0.079 to 0.003;P=0.070),seminal fluid volume(PC=-0.009;95%CI:-0.048 to-0.030;P=0.662)and sperm motility(PC=-0.17;95%CI:-0.363 to 0.022;P=0.830).In addition,the results of the subgroup analysis revealed specific variables that were associated with the decrease in relevant sperm ***:This systematic review and meta-analysis provides compelling evidence supporting a consistent negative association between exposure to ambient SO2 and semen quality parameters.

关键词： Semen quality Sulfur dioxide Ambient air pollution Meta-analysis

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Application of artificial neural networks in optimal tuning of tuned mass dampers implemented in high-rise buildings subjected to wind load

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Earthquake Engineering and Engineering Vibration 2018年第4期17卷 903-915页

作者： Meysam Ramezani Akbar Bathaei Amir k.ghorbani-tanha School of Civil Engineering College of Engineering University of Tehran

High-rise buildings are usually considered as flexible structures with low inherent damping. Therefore, these kinds of buildings are susceptible to wind-induced vibration. Tuned Mass Damper（TMD） can be used as an effective device to mitigate excessive vibrations. In this study, Artificial Neural Networks is used to find optimal mechanical properties of TMD for high-rise buildings subjected to wind load. The patterns obtained from structural analysis of different multi degree of freedom（MDF） systems are used for training neural networks. In order to obtain these patterns, structural models of some systems with 10 to 80 degrees-of-freedoms are built in MATLAB/SIMULINk program. Finally, the optimal properties of TMD are determined based on the objective of maximum displacement response reduction. The Auto-Regressive model is used to simulate the wind load. In this way, the uncertainties related to wind loading can be taken into account in neural network’s outputs. After training the neural network, it becomes possible to set the frequency and TMD mass ratio as inputs and get the optimal TMD frequency and damping ratio as outputs. As a case study, a benchmark 76-story office building is considered and the presented procedure is used to obtain optimal characteristics of the TMD for the building.

关键词： artificial neural networks tuned mass damper wind load auto-regressive model optimal frequency anddamping

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