A new control approach for seismic control of buildings equipped with active mass damper: Optimal fractional-order brain emotional learning-based intelligent controller

Abbas-Ali Zamani,Sadegh Etedali 국제구조공학회 2023 Structural Engineering and Mechanics, An Int'l Jou Vol.87 No.4

The idea of the combination of the fractional-order operators with the brain emotional learning-based intelligent controller (BELBIC) is developed for implementation in seismic-excited structures equipped with active mass damper (AMD). For this purpose, a new design framework of the mentioned combination namely fractional-order BEBIC (FOBELBIC) is proposed based on a modified-teaching-learning-based optimization (MTLBO) algorithm. The seismic performance of the proposed controller is then evaluated for a 15-story building equipped with AMD subjected to two far-field and two near-field earthquakes. An optimal BELBIC based on the MTLBO algorithm is also introduced for comparison purposes. In comparison with the structure equipped with a passive tuned mass damper (TMD), an average reduction of 44.7% and 42.8% are obtained in terms of the maximum absolute and RMS top floor displacement for FOBELBIC, while these reductions are obtained as 30.4% and 30.1% for the optimal BELBIC, respectively. Similarly, the optimal FOBELBIC results in an average reduction of 42.6% and 39.4% in terms of the maximum absolute and RMS top floor acceleration, while these reductions are given as 37.9% and 30.5%, for the optimal BELBIC, respectively. Consequently, the superiority of the FOBELBIC over the BELBIC is concluded in the reduction of maximum and RMS seismic responses.

Continuous-time Nonlinear Robust MPC for Offset-free Tracking of Piece-wise Constant Setpoints with Unknown Disturbance

Abbas Zamani,Hossein Bolandi 제어·로봇·시스템학회 2022 International Journal of Control, Automation, and Vol.20 No.4

This paper develops a novel robust tracking predictive controller for continuous-time nonlinear systems capable to deal with changing setpoints and unknown non-additive bounded disturbance. The sudden changes in a setpoint and/or existence of disturbance may lead to feasibility and stability issues if a stabilizing terminal constraint-based predictive controller is used. The robust tracking MPC presented in this paper extends the artificial reference-based nonlinear MPC for continuous-time systems and disturbance rejection. Closed-loop input-to-state stability and recursive feasibility of the optimization problem are guaranteed by tightening the terminal region, input constraint, and appropriate terminal cost function. An explicit formula that specifies the bound of sampling time interval is also introduced. We show that the proposed controller can reach an offset-free tracking if the disturbance is slowly time varying. However, in the case of non-slowly varying disturbance, a specific bound on tracking error will be guaranteed using an appropriate disturbance observation error based Lyapunov function. The satellite attitude control system simulation results are provided to show the efficiency of the proposed controller.

Seismic response of smart nanocomposite cylindrical shell conveying fluid flow using HDQ-Newmark methods

Abbas Zamani,Reza Kolahchi,Mahmood Rabani Bidgoli 사단법인 한국계산역학회 2017 Computers and Concrete, An International Journal Vol.20 No.6

In this research, seismic response of pipes is examined by applying nanotechnology and piezoelectric materials. For this purpose, a pipe is considered which is reinforced by carbon nanotubes (CNTs) and covered with a piezoelectric layer. The structure is subjected to the dynamic loads caused by earthquake and the governing equations of the system are derived using mathematical model via cylindrical shell element and Mindlin theory. Navier-Stokes equation is employed to calculate the force due to the fluid in the pipe. Mori-Tanaka approach is used to estimate the equivalent material properties of the nanocomposite and to consider the effect of the CNTs agglomeration on the scismic response of the structure. Moreover, the dynamic displacement of the structure is extracted using harmonic differential quadrature method (HDQM) and Newmark method. The main goal of this research is the analysis of the seismic response using piezoelectric layer and nanotechnology. The results indicate that reinforcing the pipeline by CNTs leads to a reduction in the displacement of the structure during an earthquake. Also the negative voltage applied to the piezoelectric layer reduces the dynamic displacement.

Stability of homomorphisms and derivations in proper JCQ^{*}-triples associated to the Pexiderized Cauchy type mapping

Abbas Najati,G. Zamani Eskandani,박춘길 대한수학회 2009 대한수학회보 Vol.46 No.1

In this paper, we investigate homomorphisms in proper JCQ^{*}-triples and derivations on proper JCQ^{*}-triples associated to the following Pexiderized functional equation [f(x+y+z) = f_{0}(x)+ f_{1}(y)+f_{2}(z)]. This is applied to investigate homomorphisms and derivations in proper JCQ^{*}-triples. In this paper, we investigate homomorphisms in proper JCQ^{*}-triples and derivations on proper JCQ^{*}-triples associated to the following Pexiderized functional equation [f(x+y+z) = f_{0}(x)+ f_{1}(y)+f_{2}(z)]. This is applied to investigate homomorphisms and derivations in proper JCQ^{*}-triples.

STABILITY OF DERIVATIONS ON PROPER LIE CQ^*-ALGEBRAS

Najati, Abbas,Eskandani, G. Zamani Korean Mathematical Society 2009 대한수학회논문집 Vol.24 No.1

In this paper, we obtain the general solution and the generalized Hyers-Ulam-Rassias stability for a following functional equation $$\sum\limits_{i=1}^mf(x_i+\frac{1}{m}\sum\limits_{{i=1\atop j{\neq}i}\.}^mx_j)+f(\frac{1}{m}\sum\limits_{i=1}^mx_i)=2f(\sum\limits_{i=1}^mx_i)$$ for a fixed positive integer m with $m\;{\geq}\;2$. This is applied to investigate derivations and their stability on proper Lie $CQ^*$-algebras. The concept of Hyers-Ulam-Rassias stability originated from the Th. M. Rassias stability theorem that appeared in his paper: On the stability of the linear mapping in Banach spaces, Proc. Amer. Math. Soc. 72(1978), 297-300.

STABILITY OF HOMOMORPHISMS AND DERIVATIONS IN PROPER JCQ^*-TRIPLES ASSOCIATED TO THE PEXIDERIZED CAUCHY TYPE MAPPING

Najati, Abbas,Eskandani, G. Zamani,Park, Choon-Kil 대한수학회 2009 대한수학회보 Vol.46 No.1

In this paper, we investigate homomorphisms in proper $JCQ^*$-triples and derivations on proper $JCQ^*$-triples associated to the following Pexiderized functional equation $$f(x+y+z)=f_0(x)+f_1(y)+f_2(z)$$. This is applied to investigate homomorphisms and derivations in proper $JCQ^*$-triples.

Bending analysis of bi-directional functionally graded Euler-Bernoulli nano-beams using integral form of Eringen’s non-local elasticity theory

Mohammad Zamani Nejad,Amin Hadi,Arash Omidvari,Abbas Rastgoo 국제구조공학회 2018 Structural Engineering and Mechanics, An Int'l Jou Vol.67 No.4

The main aim of this paper is to investigate the bending of Euler-Bernouilli nano-beams made of bi-directional functionally graded materials (BDFGMs) using Eringen‟s non-local elasticity theory in the integral form with compare the differential form. To the best of the researchers‟ knowledge, in the literature, there is no study carried out into integral form of Eringen‟s non-local elasticity theory for bending analysis of BDFGM Euler-Bernoulli nano-beams with arbitrary functions. Material properties of nano-beam are assumed to change along the thickness and length directions according to arbitrary function. The approximate analytical solutions to the bending analysis of the BDFG nano-beam are derived by using the Rayleigh-Ritz method. The differential form of Eringen‟s non-local elasticity theory reveals with increasing size effect parameter, the flexibility of the nano-beam decreases, that this is unreasonable. This problem has been resolved in the integral form of the Eringen‟s model. For all boundary conditions, it is clearly seen that the integral form of Eringen‟s model predicts the softening effect of the non-local parameter as expected. Finally, the effects of changes of some important parameters such as material length scale, BDFG index on the values of deflection of nano-beam are studied.

Improvement of performance of tetraphenylporphyrin-based red organic light emitting diodes using WO3 and C60 buffer layers

Mina Neghabi,Abbas Behjat,Bi Bi Fatemeh Mirjalili,Leila Zamani 한국물리학회 2013 Current Applied Physics Vol.13 No.1

One of the porphyrin derivatives, meso-tetraphenylporphyrin (TPP), has been synthesized and examined as an emitter material (EM) for efficient fluorescent red organic light-emitting diodes (OLEDs). By inserting a tungsten oxide (WO3) layer into the interface of anode (ITO) and hole transport layer N,N0-Di-[(1-napthyl)-N,N0-diphenyl]-(1,10-biphenyl)-4,40-diamine (NPB) and by using fullerene (C60) in contact with a LiF/Al cathode, the performance of devices was markedly improved. The current densityevoltageeluminance (JeVeL) characterizations of the samples show that red OLEDs with both WO3 and C60 as buffer layers have a lower driving voltage and higher luminance compared with the devices without buffer layers. The red OLED with the configuration ITO/WO3 (3 nm)/NPB (50 nm)/TPP (60 nm)/BPhen (30 nm)/C60 (5 nm)/LiF (0.8 nm)/Al (100 nm) achieved the high luminance of 6359 cd/m2 at the low driving voltage of 8 V. At a current density of 20 mA/cm2, a pure red emission with CIE coordinates of (0.65; 0.35) is observed for this device. Moreover, a power efficiency of 2.07 lm/W and a current efficiency of 5.17 cd/A at 20 mA/cm2 were obtained for the fabricated devices. The study of the energy level diagram of the devices revealed that the improvement in performance of the devices with buffer layers could be attributed to lowering of carrier-injecting barrier and more balanced charge injection and transport properties.

Bending analysis of bi-directional functionally graded Euler-Bernoulli nano-beams using integral form of Eringen's non-local elasticity theory

Nejad, Mohammad Zamani,Hadi, Amin,Omidvari, Arash,Rastgoo, Abbas Techno-Press 2018 Structural Engineering and Mechanics, An Int'l Jou Vol.67 No.4

The main aim of this paper is to investigate the bending of Euler-Bernouilli nano-beams made of bi-directional functionally graded materials (BDFGMs) using Eringen's non-local elasticity theory in the integral form with compare the differential form. To the best of the researchers' knowledge, in the literature, there is no study carried out into integral form of Eringen's non-local elasticity theory for bending analysis of BDFGM Euler-Bernoulli nano-beams with arbitrary functions. Material properties of nano-beam are assumed to change along the thickness and length directions according to arbitrary function. The approximate analytical solutions to the bending analysis of the BDFG nano-beam are derived by using the Rayleigh-Ritz method. The differential form of Eringen's non-local elasticity theory reveals with increasing size effect parameter, the flexibility of the nano-beam decreases, that this is unreasonable. This problem has been resolved in the integral form of the Eringen's model. For all boundary conditions, it is clearly seen that the integral form of Eringen's model predicts the softening effect of the non-local parameter as expected. Finally, the effects of changes of some important parameters such as material length scale, BDFG index on the values of deflection of nano-beam are studied.

Free vibrations analysis of arbitrary three-dimensionally FGM nanoplates

Dehshahri, Kasra,Nejad, Mohammad Zamani,Ziaee, Sima,Niknejad, Abbas,Hadi, Amin Techno-Press 2020 Advances in nano research Vol.8 No.2

In this paper, the free vibrations analysis of the nanoplates made of three-directional functionally graded material (TDFGM) with small scale effects is presented. To study the small-scale effects on natural frequency, modified strain gradient theory (MSGT) has been used. Material properties of the nanoplate follow an arbitrary function that changes in three directions along the length, width and thickness of the plate. The equilibrium equations and boundary conditions of nanoplate are obtained using the Hamilton's principle. The generalized differential quadrature method (GDQM) is used to solve the governing equations and different boundary conditions for obtaining the natural frequency of nanoplate made of three-directional functionally graded material. The present model can be transformed into a couple stress plate model or a classic plate model if two or all parameters of the length scales set to zero. Finally, numerical results are presented to study the small-scale effect and heterogeneity constants and the aspect ratio with different boundary conditions on the free vibrations of nanoplates. To the best of the researchers' knowledge, in the literature, there is no study carried out into MSGT for free vibration analysis of FGM nanoplate with arbitrary functions.