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Kourosh H. Shirazi

Bio: Kourosh H. Shirazi is an academic researcher from Shahid Chamran University of Ahvaz. The author has contributed to research in topics: Nonlinear system & Finite element method. The author has an hindex of 15, co-authored 55 publications receiving 722 citations.


Papers
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Journal ArticleDOI
TL;DR: In this paper, the quintic non-linear equation of motion is derived based on Hamilton's principle and solved by means of an analytical technique, namely the Homotopy analysis method.
Abstract: non-linear vibration analysis of beam used in steel structures is of particular importance in mechanical and industrial applications. To achieve a proper design of the beam structures, it is essential to realize how the beam vibrates in its transverse mode which in turn yields the natural frequency of the system. Equation of transversal vibration of hinged–hinged flexible beam subjected to constant excitation at its free end is identified as a non-linear differential equation. The quintic non-linear equation of motion is derived based on Hamilton’s principle and solved by means of an analytical technique, namely the Homotopy analysis method. To verify the soundness of the results, a comparison between analytical and numerical solutions is developed. Finally, to express the impact of the quintic nonlinearity, the non-linear responses obtained by HAM are compared with the results from usual beam theory.

75 citations

Journal ArticleDOI
TL;DR: In this article, the roll steer of a front McPherson suspension system is studied and the design characteristics of mechanism are optimized using Genetic Algorithm method and a set of mathematical equations are derived to determine the suspension behavior of a typical vehicle through the rolling.

54 citations

Journal ArticleDOI
TL;DR: In this paper, a new asymptotic procedure is presented to predict the nonlinear vibrational behavior of micro-beams pre-deformed by an electric field, which includes both even and odd nonlinearities.

53 citations

Journal ArticleDOI
TL;DR: In this article, an exact equivalent function (EF) for deadzone nonlinearity in an analytical investigation of nonlinear differential equations is presented. And the analytical solution of dynamic behavior of the mentioned system, a powerful method, called He's parameter expanding method (HPEM) is used.
Abstract: This paper presents the application of novel and reliable exact equivalent function (EF) for deadzone nonlinearity in an analytical investigation of nonlinear differential equations. A highly nonlinear equation of cantilever beam vibration with a deadzone nonlinear boundary condition is used to indicate the effectiveness of this EF. To obtain the analytical solution of dynamic behavior of the mentioned system, a powerful method, called He’s parameter expanding method (HPEM) is used. Comparison of the obtained solutions using a numerical method reveals the accuracy of this analytical EF. [DOI: 10.1115/1.4005924]

49 citations

Journal ArticleDOI
TL;DR: In this article, a nonlinear frequency-amplitude relation is developed to investigate the vibrational amplitude effect on the dynamic pull-in instability of double-sided-actuated nano-torsional switches.

45 citations


Cited by
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01 Jan 1992
TL;DR: Two novel algorithms to realize a finite dimensional, linear time-invariant state-space model from input-output data are presented: an RQ factorization followed by a singular value decomposition and the solution of an overdetermined set of equations.
Abstract: In this paper, we present two novel algorithms to realize a finite dimensional, linear time-invariant state-space model from input-output data. The algorithms have a number of common features. They are classified as one of the subspace model identification schemes, in that a major part of the identification problem consists of calculating specially structured subspaces of spaces defined by the input-output data. This structure is then exploited in the calculation of a realization. Another common feature is their algorithmic organization: an RQ factorization followed by a singular value decomposition and the solution of an overdetermined set (or sets) of equations. The schemes assume that the underlying system has an output-error structure and that a measurable input sequence is available. The latter characteristic indicates that both schemes are versions of the MIMO Output-Error State Space model identification (MOESP) approach. The first algorithm is denoted in particular as the (elementary MOESP scheme)...

660 citations

Journal ArticleDOI
TL;DR: In this paper, the authors quantitatively analyzed and evaluated current research status of energy management strategies for HEVs based on bibliometrics for the first time, through content analysis involving analysis of author keywords and abstracts.
Abstract: Hybrid electric vehicles (HEVs) are one of the most viable technologies to achieve the goals of energy saving and environmental protection before a breakthrough in battery technology and fuel cell technology. Energy management strategy as a key technology of HEVs is studied extensively and deeply to improve the performance of HEVs and speed up the industrialization of HEVs. This paper quantitatively analyzes and evaluates current research status of energy management strategies for HEVs based on bibliometrics for the first time, through content analysis involving analysis of author keywords and abstracts. Then qualitative analysis is performed for all kinds of energy management strategies that are used in HEVs in detail, essential characteristics involving pros and cons, interconnections and improvement potential among various energy management strategies are revealed from the view of control theory. Finally, latest developing trends in energy management strategies of HEVs are presented to improve the performance of HEVs based on above quantitative analysis and qualitative analysis, covering driving cycle recognition/prediction algorithms, integrated multi-objective, coordinated optimization energy management strategies, good balance between computation complexity and optimization performance of energy management strategies, fair and credible evaluation system of energy management strategies. This paper not only first provides a comprehensive analysis of energy management strategies for HEVs, but also puts forward the emphasis and orientation of future study, which will broaden relevant researchers׳ vision and promote the development of a simple and practical energy management controller with low cost and high performance for HEVs.

288 citations

Journal ArticleDOI
TL;DR: Various powertrain systems and topologies of (plug-in) hybrid electric vehicles and full-electric vehicles are assessed and EMSs as applied in the literature are systematically surveyed for a qualitative investigation, classification, and comparison through a comprehensive review.
Abstract: Hybrid and electric vehicles have been demonstrated as auspicious solutions for ensuring improvements in fuel saving and emission reductions. From the system design perspective, there are numerous indicators affecting the performance of such vehicles, in which the powertrain type, component configuration, and energy management strategy (EMS) play a key role. Achieving an energy-efficient powertrain requires tackling several conflicting control objectives such as the drivability, fuel economy, reduced emissions, and battery state of charge preservation, which make the EMS the most crucial aspect of powertrain system design. Accordingly, in the present study, various powertrain systems and topologies of (plug-in) hybrid electric vehicles and full-electric vehicles are assessed. In addition, EMSs as applied in the literature are systematically surveyed for a qualitative investigation, classification, and comparison of existing approaches in terms of the principles, advantages, and drawbacks through a comprehensive review. Furthermore, potential challenges considering the gaps in research are addressed, and directives paving the way toward further development of powertrains and EMSs in all respects are thoroughly provided.

261 citations

Journal ArticleDOI
TL;DR: This work aims to provide a comprehensive scientific publication on the current status and future expectations of fuel cells in the vehicle industry to engineers and researchers interested in this field.
Abstract: The implementations of fuel cells (FCs) in the vehicle industry have gained great attention for the last few decades owing to simple utilization, silent operation, high efficiency and modular structure. Technological advancements show that the use of FCs in electric vehicles (EVs) will increase rapidly and cause a revolution, and will be an alternative to traditional vehicles in the future. Commercial vehicles, projects and research show that work is underway to ensure that FCEVs have sufficient performance advances for their daily transportation needs. However, the lack of a detailed study that will shed light on researchers working in this field is obvious. It aims to provide a comprehensive scientific publication on the current status and future expectations to engineers and researchers interested in this field. In the current study, numerous studies have been examined in detail and added as supplementary to the bibliography. In this context, FCEVs are classified under headings of configurations, systems components, control/management, technical challenges, marketing and future aspects. First of all, FC types and electric motors are discussed in terms of their application areas, characteristic properties and operating conditions. Power converters, which are voltage regulation and motor drive topologies used in FCEVs, are detailed according to the structural frequency of use, structure, and complexity. In the next sections, control issues for converters and technical challenges are branched for FCEVs. In final section, the current status and future aspects are reported using a large number of marketing and target data.

211 citations

01 Jan 2005
TL;DR: In this paper, an approximate analytical expression of the critical pull-in gap with Casimir force is presented by the perturbation theory, from which one can notice the nonlinear effect of Casimir forces on the pullin parameters.
Abstract: Casimir effect on the critical pull-in gap and pull-in voltage of nanoelectromechanical switches is studied. An approximate analytical expression of the critical pull-in gap with Casimir force is presented by the perturbation theory. The corresponding pull-in parameters are computed numerically, from which one can notice the nonlinear effect of Casimir force on the pull-in parameters. The detachment length has been presented, which increases with increasing thickness of the beam.

192 citations