Loading...
Search for:
mahboobi--h
0.109 seconds
Total 8866 records
Molecular dynamics study of bio-manipulation in aqueous media
, Article Micro and Nano Letters ; Volume 11, Issue 1 , 2016 , Pages 9-14 ; 17500443 (ISSN) ; Pishkenari, H. N ; Mahboobi, S. H ; Sharif University of Technology
Institution of Engineering and Technology
2016
Abstract
Nano-manipulation is one of the most important aspects of nano-robotics and nano-assembly. The positioning process is considered by many researches to be one of the most important parts of nano-assembly, but has been poorly investigated, particularly for biologic samples. This Letter is devoted to modelling the process of positioning a biomolecule with atomic force microscopy (AFM) in an aqueous media using molecular dynamics simulations. Carbon nanotube (CNT) and graphite sheet are selected as AFM tip and substrate, respectively. To consider the effects of the medium on the manipulation, several models for decreasing the calculations including implicit, coarse grained, and all-atom methods...
Dynamic modeling and sensitivity analysis of atomic force microscope pushing force in nanoparticle manipulation on a rough substrate [electronic resource]
, Article Journal of Advanced Science, Engineering and Medicine ; 2013, Vol. 5, pp. 1-10 ; Mahboobi, Seyed Hanif ; Meghdari, Ali ; Sharif University of Technology
Abstract
An Atomic Force Microscope (AFM) is a capable tool to manipulate nanoparticles by exerting pushing force on the nanoparticles located on the substrate. In reality, the substrate cannot be considered as a smooth surface particularly at the nanoscale. Hence, the particle may encounter a step on the substrate during a manipulation. In this study, dynamics of the nanoparticle on a stepped substrate and critical pushing force in the manipulation are investigated. There are two possible dynamic modes that may happen in the manipulation on the stepped substrate. In one mode, the nanoparticle may slide on the step edge and then climb up to the step which is a desired mode. Another possible mode is...
Modal analysis of metallic nanocantilevers with FCC lattice using atomic approximation method
, Article 2006 ASME International Mechanical Engineering Congress and Exposition, IMECE2006, Chicago, IL, 5 November 2006 through 10 November 2006 ; 2006 ; 1096665X (ISSN); 0791837904 (ISBN); 9780791837900 (ISBN) ; Pishkenari, H. N ; Mahboobi, S. H ; Meghdari, A ; Sharif University of Technology
American Society of Mechanical Engineers (ASME)
2006
Abstract
In this research, we will use an accelerator for MD simulations, called Atomic Approximation Method, which leads to more efficient simulations without harming the physical properties in simulations. The main idea of this method is to define a virtual material with lower number of atoms, which has the same physical properties as the original material. To demonstrate the validity of the proposed technique the modal analysis results are compared with the ones of the conventional molecular dynamics method. It is shown that this method accelerates conventional MD simulations significantly. Copyright © 2006 by ASME
Adaptive regulation and set-point tracking of the Lorenz attractor
, Article Chaos, Solitons and Fractals ; Volume 32, Issue 2 , 2007 , Pages 832-846 ; 09600779 (ISSN) ; Shahrokhi, M ; Mahboobi, S. H ; Sharif University of Technology
2007
Abstract
In this paper, an approach is proposed for controlling the uncertain Lorenz system. Based on an identification technique, a controller is designed that guarantees the regulation of all states in the presence of system uncertainty. Since in some applications the challenging problem of output tracking is desired, we have proposed several effective set-point tracking control techniques. The control schemes that are based on the feedback linearization method, can stabilize the internal dynamics of the system. Simulation results have illustrated the effectiveness of the proposed schemes. © 2005 Elsevier Ltd. All rights reserved
Observer-based control design for three well-known chaotic systems
, Article Chaos, Solitons and Fractals ; Volume 29, Issue 2 , 2006 , Pages 381-392 ; 09600779 (ISSN) ; Shahrokhi, M ; Pishkenari, H. N ; Sharif University of Technology
2006
Abstract
In this paper, a singularity-free approach is proposed for controlling three well-known chaotic systems namely Lorenz, Chen and Lu. The control design guarantees the regulation of two states and boundedness of the remaining state. The stability of the proposed scheme has been shown using the Lyapunov stability theorem. Implementation of the proposed control technique requires system states, while in most of practical applications only the system output is available. To overcome this problem, a nonlinear observer is coupled with the controller. Simulation results have illustrated the effectiveness and robustness of the proposed schemes. If the control action is applied to the second system...
Molecular dynamics simulation of manipulation of metallic nanoclusters on double-layer substrates [electronic resource]
, Article Physica E: Low-dimensional Systems and Nanostructures ; 2010, Vol. 42, No. 9, pp. 2364-2374 ; Meghdari, Ali ; Jalili, Nader ; Amiri, Farshid ; Sharif University of Technology
Abstract
Molecular dynamics simulations are carried out to investigate the manipulation of metallic clusters on double-layer surfaces. The system parts are made of transition metals. The conditions which are subjected to change in the tests are material combinations for cluster, main substrate and lubricant layer (adlayer). In addition to qualitative observations, two criteria which represent the particle deformation and substrate abrasion are utilized as evaluation tools and are computed for each case. Obtaining this sort of knowledge is highly beneficial for further experiments in order to be able to plan the conditions and routines, which guarantee better success in the manipulation process
Robust adaptive backstepping control of uncertain Lorenz system
, Article Chaos ; Vol. 20, issue. 2 , 2010 ; ISSN: 10541500 ; Jalili, N ; Mahboobi, S. H ; Alasty, A ; Meghdari, A ; Sharif University of Technology
2010
Abstract
In this paper, a novel robust adaptive control method is proposed for controlling the Lorenz chaotic attractor. A new backstepping controller for the Lorenz system based on the Lyapunov stability theorem is proposed to overcome the singularity problem that appeared in using the typical backstepping control method. By exploiting the property of the system, the resulting controller is shown to be singularity free and the closed loop system is globally stable. Due to unavailability of system states measurement in practice, the controller is selected such that only one system state is needed. To overcome the problem of parameter uncertainty, an additional term to Lyapunov function is added and...
Manipulation of biomolecules: A molecular dynamics study
, Article Current Applied Physics ; Volume 14, Issue 9 , September , 2014 , Pages 1216-1227 ; ISSN: 15671739 ; Nejat Pishkenari, H ; Mahboobi, S. H ; Meghdari, A ; Sharif University of Technology
2014
Abstract
With the rapid progression of bionanorobotics, manipulation of nano-scale biosamples is becoming increasingly attractive for different biological purposes. Nevertheless, the interaction between a robotic probe and a biological sample is poorly understood and the conditions for appropriate handling is not well-known. Here, we use the molecular dynamics (MD) simulation method to investigate the manipulation process when a nanoprobe tries to move a biosample on a substrate. For this purpose, we have used Ubiquitin (UBQ) as the biomolecule, a single-walled carbon nanotube (SWCNT) as the manipulation probe, and a double-layered graphene sheets as the substrate. A series of simulations were...
Optimum design and vibration suppression of a piezoelectric amplified microactuator using FEM analysis
, Article s20th International Microprocesses and Nanotechnology Conference, MNC 2007, Kyoto, 5 November 2007 through 8 November 2007 ; February , 2007 , Pages 378-379 ; 4990247248 (ISBN); 9784990247249 (ISBN) ; Shahidi, A ; Pirouzpanah, S ; Esteki, H ; Sarkar, S ; Sharif University of Technology
2007
Abstract
In this research the optimum design of a piezoelectric amplified microactuator has been achieved via equation (1) and sensitivity analysis in FEM simulation software. In addition, for the sake of simplicity and utilizing the FEM software simulation facilities, the control strategy has been embedded in FEM simulation as a programming routine. The simulations showed the efficiency of the proposed controller to suppress the microactuator's undesired vibrations
A novel approach for optimal design of a rover mechanism
, Article Journal of Intelligent and Robotic Systems: Theory and Applications ; Volume 44, Issue 4 , 2005 , Pages 291-312 ; 09210296 (ISSN) ; Pishkenari, H. N ; Gaskarimahalle, A. L ; Mahboobi, S. H ; Karimi, R ; Sharif University of Technology
2005
Abstract
This article presents an overview of the mechanical design and fabrication of a Rescue Robot (CEDRA) for operation in unstructured environments. In order to obtain an appropriate mechanism for climbing the stairs, a novel method has been developed. In this kinematics-based approach we don't need to perform any dynamic analysis which is highly complicated and time consuming for most rovers. According to the essential characteristics needed for rovers, two objective functions were defined. We have shown that the new mechanism performs better on rough terrains than the previous well-known mechanism widely used in the Mars rovers. Moreover the design parameters are optimized by means of Genetic...
An effective approach for dynamic analysis of rovers
, Article Robotica ; Volume 23, Issue 6 , 2005 , Pages 771-780 ; 02635747 (ISSN) ; Karimi, R ; Pishkenari, H. N ; Gaskarimahalle, A. L ; Mahboobi, S. H ; Sharif University of Technology
2005
Abstract
In this paper a novel approach to dynamic formulation of rovers has been presented. The complexity of these multi-body systems especially on rough terrain, challenged us to use the Kane's method which has been preferred to others in these cases. As an example, symbolic equations of a six-wheeled rover, named CEDRA Rescue Robot which uses a shrimp like mechanism, have been derived and a simulation of forward and inverse dynamics has been presented. Due to the clear form of equations, each term defines a physical meaning which represents the effect of each parameter, resulting in a frame-work for performance comparison of rovers. Although the method has been described for a 2-D non-slipping...
Optimal design and fabrication of "CEDRA" rescue robot using genetic algorithm
, Article 2004 ASME Design Engineering Technical Conferences and Computers and Information in Engineering Conference, Salt Lake City, UT, 28 September 2004 through 2 October 2004 ; Volume 2 A , 2004 , Pages 541-548 ; Pishkenari, H. N ; Gaskarimahalle, A. L ; Mahboobi, S. H ; Karimi, R ; Sharif University of Technology
American Society of Mechanical Engineers
2004
Abstract
This article presents an overview of the mechanical design features, fabrication and control of a Rescue Robot (CEDRA) for operation in unstructured environments. As a preliminary step, the essential characteristics of a robot in damaged and unstable situations have been established. According to these features and kinematical equations of the robot, design parameters are optimized by means of Genetic Algorithm. Optimum parameters are then utilized in construction. Upon fabrication, this unit has been tested in clean laboratory environment, as well as, ill-conditioned arenas similar to earthquake zones. The obtained results have been satisfactory in all aspects, and improvements are...
Simulation of imaging in tapping-mode atomic-force microscopy: a comparison amongst a variety of approaches
, Article Journal of Physics D: Applied Phyics ; Vol.44, Number 7, p.1-9, 2011 ; Mahboobi, S. H ; Meghdari, A. (Ali) ; Sharif University of Technology
Abstract
Models capable of accurate simulation of microcantilever dynamics coupled with complex tip–sample interactions are essential for interpretation and prediction of the imaging results in amplitude modulation or tapping-mode atomic-force microscopy (AM-AFM or TM-AFM). In this paper, four approaches based on combinations of lumped and finite element methods for modelling of cantilever dynamics, and van der Waals and molecular dynamics for modelling of tip–sample interactions, are used to simulate the precise imaging by AM-AFM. Based on the simulated imaging and force determination, the efficiency of different modelling schemes is evaluated. This comparison is performed considering their...
Robust adaptive backstepping control of uncertain Lorenz system
, Article Chaos ; Volume 20, Issue 2 , 2010 ; 10541500 (ISSN) ; Jalili, N ; Mahboobi, S. H ; Alasty, A ; Meghdari, A ; Sharif University of Technology
2010
Abstract
In this paper, a novel robust adaptive control method is proposed for controlling the Lorenz chaotic attractor. A new backstepping controller for the Lorenz system based on the Lyapunov stability theorem is proposed to overcome the singularity problem that appeared in using the typical backstepping control method. By exploiting the property of the system, the resulting controller is shown to be singularity free and the closed loop system is globally stable. Due to unavailability of system states measurement in practice, the controller is selected such that only one system state is needed. To overcome the problem of parameter uncertainty, an additional term to Lyapunov function is added and...
Molecular Dynamics Simulation of Nanoscale Effects in Nanomanipulation
, Ph.D. Dissertation Sharif University of Technology ; Meghdari, Ali (Supervisor)
Abstract
Metallic clusters are among the best candidates that may be utilized as building blocks for constructing nanostructures. Despite their great potential, a variety of questions arises about their suitability as building blocks at the nanoscale level. One of the key factors in the assembly of nanoclusters is the precise positioning that is required by a manipulation system. The response of clusters, which are subjected to this process, is of great importance. Currently, the size of clusters used as building blocks is shrinking down to a few nanometers. In such cases, the particle nature of matter plays an important role in manipulator/cluster/substrate interactions. Having a deeper insight into...
Robust adaptive backstepping control of uncertain lorenz system [electronic resource]
, Article Journal of American Institute of Physics ; 2010, Vol. 20, pp. 1-5 ; Jalili, Nader ; Mahboobi, Seyed Hanif ; Alasty, Aria ; Meghdari, Ali ; Sharif University of Technology
Abstract
In this paper, a novel robust adaptive control method is proposed for controlling the Lorenz chaotic attractor. A new backstepping controller for the Lorenz system based on the Lyapunov stability theorem is proposed to overcome the singularity problem that appeared in using the typical backstepping control method. By exploiting the property of the system, the resulting controller is shown to be singularity free and the closed loop system is globally stable. Due to unavailability of system states measurement in practice, the controller is selected such that only one system state is needed. To overcome the problem of parameter uncertainty, an additional term to Lyapunov function is added and...
Molecular dynamics study of success evaluation for metallic nanoparticles manipulation on gold substrate
, Article Proceedings of the ASME International Design Engineering Technical Conferences and Computers and Information in Engineering Conference 2009, DETC2009, 30 August 2009 through 2 September 2009 ; Volume 6 , August–September , 2010 , Pages 345-346 ; 9780791849033 (ISBN) ; Meghdari, A ; Jalili, N ; Sharif University of Technology
2010
Abstract
Using molecular dynamics, the behavior of nanoparticles during manipulation process is investigated in this paper. The system consists of a tip, cluster and substrate. The focus of the present research is on ultra-fine metallic nanoclusters. The system of concern is made of different transition metals. Two criteria have been proposed for evaluation of success in a pushing process. Such criteria describe the intactness of nanoparticle/substrate pair. The effects of cluster material and manipulation speed on the success of the process are investigated by atomistic simulations. Such qualitative simulation studies can evaluate the level of success of manipulation regarding different working...
Molecular dynamics study of success evaluation for metallic nanoparticles manipulation on gold substrate
, Article Proceedings of the ASME Design Engineering Technical Conference, 30 August 2009 through 2 September 2009, San Diego, CA ; Volume 6 , 2009 , Pages 345-346 ; 9780791849033 (ISBN) ; Meghdari, A ; Jalili, N ; Sharif University of Technology
2009
Abstract
Using molecular dynamics, the behavior of nanoparticles during manipulation process is investigated in this paper. The system consists of a tip, cluster and substrate. The focus of the present research is on ultra-fine metallic nanoclusters. The system of concern is made of different transition metals. Two criteria have been proposed for evaluation of success in a pushing process. Such criteria describe the intactness of nanoparticle/substrate pair. The effects of cluster material and manipulation speed on the success of the process are investigated by atomistic simulations. Such qualitative simulation studies can evaluate the level of success of manipulation regarding different working...
Developing a Molecular Dynamics Simulation Software for Modeling of Nano-Contact Processes (CEDRA Molecular Dynamics Software )
,
M.Sc. Thesis
Sharif University of Technology
;
Meghdari, Ali
(Supervisor)
;
Mahboobi, Hanif
(Supervisor)
Abstract
Molecular Dynamics as a powerful method in the field of Nano-simulation has been widely used in recent years. Different contact processes such as Nano-manipulation, AFM Imaging, and Nano-indentation can be simulated using this method. There have been numerous researches done on calculating techniques of simulation of different phenomena in Nano-technology. Specifically, friction and Nano-indentation which are parts of Nano-contact processes have been simulated by different investigators. However, on some other parts, e.g. Nano-manipulation and AFM Imaging, there are few studies done up to now. Thus, a simulation and computational software seems necessary in this field. The main goal of...
Qualitative study of nanocluster positioning process: 2D molecular dynamics simulations
, Article 2008 ASME International Mechanical Engineering Congress and Exposition, IMECE 2008, Boston, MA, 31 October 2008 through 6 November 2008 ; Volume 13, Issue PART B , 2009 , Pages 1161-1170 ; 9780791848746 (ISBN) ; Meghdari, A ; Jalili, N ; Amiri, F ; Sharif University of Technology
2009
Abstract
One of the key factors in the assembly of nanoclusters is the precise positioning of them by a manipulation system. Currently the size of clusters used as building blocks is shrinking down to a few nanometers. In such cases, the particle nature of matter plays an important role in the manipulator/cluster/substrate interactions. Having a deeper insight to the aforementioned nanoscale interactions is crucial for prediction and understanding of the behavior of nanoclusters during the positioning process. In the present research, 2D molecular dynamics simulations have been used to investigate such behaviors. Performing planar simulations can provide a fairly acceptable qualitative tool for our...