Process Metamorphosis and On-Line FEM for Mathematical Modeling of Metal Rolling-Part I: Theory

Zamanian, A.,Nam, S.Y.,Shin, T.J.,Hwang, S.M. The Korean Society for Technology of Plasticity 2019 소성가공 : 한국소성가공학회지 Vol.28 No.2

This paper introduces a new concept - on-line FE model, as applied to metal rolling. The new technology allows for completion of process simulation within a tiny fraction of a second without loss of high-level prediction accuracy inherent to FEM. The three steps of an on-line FE model design namely, process metamorphosis, mesh design, and process variable design, are described in detail. The procedure is demonstrated step by step through designing actual on-line models for the prediction of the dog-bone profile in edge rolling. The validity and prediction accuracy of the on-line FE models are analyzed and discussed.

Religious Coping and Quality of Life in Women with Breast Cancer

Zamanian, Hadi,Eftekhar-Ardebili, Hasan,Eftekhar-Ardebili, Mehrdad,Shojaeizadeh, Davood,Nedjat, Saharnaz,Taheri-Kharameh, Zahra,Daryaafzoon, Mona Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.17

Background: The aim of this study was to assess the predictive role of religious coping in quality of life of breast cancer patients. Materials and Methods: This multi-center cross-sectional study was conducted in Tehran, Iran, from October 2014 to May 2015. A total of 224 women with breast cancer completed measures of socio-demographic information, religious coping (brief RCOPE), and quality of life (FACT-B). Data were analyzed using descriptive statistics and the t-test, ANOVA, and linear regression analysis. Results: The mean age was 47.1 (SD=9.07) years and the majority were married (81.3%). The mean score for positive religious coping was 22.98 (SD=4.09) while it was 10.13 (SD=3.90) for negative religious coping. Multiple linear regression showed positive and negative religious coping as predictor variables explained a significant amount of variance in overall QOL score ($R^2=.22$, P=.001) after controlling for socio-demographic, and clinical variables. Positive religious coping was associated with improved QOL (${\beta}=0.29$; p=0.001). In contrast, negative religious coping was significantly associated with worse QOL (${\beta}=-0.26$; p=0.005). Conclusions: The results indicated the used types of religious coping strategies are related to better or poorer QOL and highlight the importance of religious support in breast cancer care.

Secondary resonances of a microresonator under AC-DC electrostatic and DC piezoelectric actuations

Zamanian, M.,Hosseini, S.A.A. Techno-Press 2012 Structural Engineering and Mechanics, An Int'l Jou Vol.42 No.5

This article studies the secondary resonances of a clamped-clamped microresonator under combined electrostatic and piezoelectric actuations. The electrostatic actuation is induced by applying the AC-DC voltage between the microbeam and the electrode plate that lies at the opposite side of the microbeam. The piezoelectric actuation is induced by applying the DC voltage between upper and lower sides of piezoelectric layer. It is assumed that the neutral axis of bending is stretched when the microbeam is deflected. The drift effect of piezoelectric layer (the phenomenon where there is a slow increase of the free strain after the application of a DC field) is neglected. The equations of motion are solved by using the multiple scale perturbation method. The system possesses a subharmonic resonance of order one-half and a superharmonic resonance of order two. It is shown that using the DC piezoelectric actuation, the sensitivity of AC-DC electrostatically actuated microresonator under subharmonic and superharmonic resonances may be tuned. In addition, it is shown that the tuning domain of the microbeam under combined electrostatic and piezoelectric actuations at subharmonic and superharmonic conditions is larger than the tuning domain of microbeam under only the electrostatic actuation.

Process Metamorphosis and On-Line FEM for Mathematical Modeling of Metal Rolling-Part II: Application

Zamanian, A.,Nam, S.Y.,Shin, T.J.,Hwang, S.M. The Korean Society for Technology of Plasticity 2019 소성가공 : 한국소성가공학회지 Vol.28 No.2

In this paper, we examine the application of a new concept - on-line FE model in various metal rolling processes. This technology allows for completion of process simulation within a tiny fraction of a second without losing the high level of prediction accuracy inherent to FEM. The procedure is systematically demonstrated through the design of actual on-line models for the prediction of the width spread in horizontal rolling of the slab using a dog bone profile and horizontal rolling of the strip with a strip profile. The validity and the prediction accuracy of the on-line FE models were analyzed and discussed.

Agglomeration effects on the buckling behaviour of embedded concrete columns reinforced with SiO₂ nano-particles

Zamanian, Mohammad,Kolahchi, Reza,Bidgoli, Mahmood Rabani Techno-Press 2017 Wind and Structures, An International Journal (WAS Vol.24 No.1

The use of nanotechnology materials and applications in the construction industry should be considered for enhancing material properties. However, the nonlinear buckling of an embedded straight concrete columns reinforced with silicon dioxide ($SiO_2$) nanoparticles is investigated in the present study. The column is simulated mathematically with Euler-Bernoulli and Timoshenko beam models. Agglomeration effects and the characteristics of the equivalent composite are determined using Mori-Tanaka approach. The foundation around the column is simulated with spring and shear layer. The governing equations are derived using energy method and Hamilton's principal. Differential quadrature method (DQM) is used in order to obtain the buckling load of structure. The influences of volume percent of $SiO_2$ nanoparticles, geometrical parameters and agglomeration on the buckling of column are investigated. Numerical results indicate that considering agglomeration effects leads to decrease in buckling load of structure.

Nonlinear response of a resonant viscoelastic microbeam under an electrical actuation

Zamanian, M.,Khadem, S.E.,Mahmoodi, S.N. Techno-Press 2010 Structural Engineering and Mechanics, An Int'l Jou Vol.35 No.4

In this paper, using perturbation and Galerkin method, the response of a resonant viscoelastic microbeam to an electric actuation is obtained. The microbeam is under axial load and electrical load. It is assumed that midplane is stretched, when the beam is deflected. The equation of motion is derived using the Newton's second law. The viscoelastic model is taken to be the Kelvin-Voigt model. In the first section, the static deflection is obtained using the Galerkin method. Exact linear symmetric mode shape of a straight beam and its deflection function under constant transverse load are used as admissible functions. So, an analytical expression that describes the static deflection at all points is obtained. Comparing the result with previous research show that using deflection function as admissible function decreases the computation errors and previous calculations volume. In the second section, the response of a microbeam resonator system under primary and secondary resonance excitation has been obtained by analytical multiple scale perturbation method combined with the Galerkin method. It is shown, that a small amount of viscoelastic damping has an important effect and causes to decrease the maximum amplitude of response, and to shift the resonance frequency. Also, it shown, that an increase of the DC voltage, ratio of the air gap to the microbeam thickness, tensile axial load, would increase the effect of viscoelastic damping, and an increase of the compressive axial load would decrease the effect of viscoelastic damping.

Process Metamorphosis and On-Line FEM for Mathematical Modeling of Metal Rolling-Part I: Theory

A.Zamanian,남승연,신태진,황상무 한국소성∙가공학회 2019 소성가공 : 한국소성가공학회지 Vol.28 No.2

This paper introduces a new concept – on-line FE model, as applied to metal rolling. The new technology allows for completion of process simulation within a tiny fraction of a second without loss of high-level prediction accuracy inherent to FEM. The three steps of an on-line FE model design namely, process metamorphosis, mesh design, and process variable design, are described in detail. The procedure is demonstrated step by step through designing actual on-line models for the prediction of the dog-bone profile in edge rolling. The validity and prediction accuracy of the on-line FE models are analyzed and discussed.

Process Metamorphosis and On-Line FEM for Mathematical Modeling of Metal Rolling-Part II: Application

A.Zamanian,남승연,신태진,황상무 한국소성∙가공학회 2019 소성가공 : 한국소성가공학회지 Vol.28 No.2

In this paper, we examine the application of a new concept – on-line FE model in various metal rolling processes. This technology allows for completion of process simulation within a tiny fraction of a second without losing the high level of prediction accuracy inherent to FEM. The procedure is systematically demonstrated through the design of actual on-line models for the prediction of the width spread in horizontal rolling of the slab using a dog bone profile and horizontal rolling of the strip with a strip profile. The validity and the prediction accuracy of the on-line FE models were analyzed and discussed.

Agglomeration effects on the buckling behaviour of embedded concrete columns reinforced with SiO2 nano-particles

Mehdi Zamanian,Reza Kolahchi,Mahmood Rabani Bidgoli 한국풍공학회 2017 Wind and Structures, An International Journal (WAS Vol.24 No.1

The use of nanotechnology materials and applications in the construction industry should be considered for enhancing material properties. However, the nonlinear buckling of an embedded straight concrete columns reinforced with silicon dioxide (SiO2) nanoparticles is investigated in the present study. The column is simulated mathematically with Euler-Bernoulli and Timoshenko beam models. Agglomeration effects and the characteristics of the equivalent composite are determined using Mori-Tanaka approach. The foundation around the column is simulated with spring and shear layer. The governing equations are derived using energy method and Hamilton\'s principal. Differential quadrature method (DQM) is used in order to obtain the buckling load of structure. The influences of volume percent of SiO2 nanoparticles, geometrical parameters and agglomeration on the buckling of column are investigated. Numerical results indicate that considering agglomeration effects leads to decrease in buckling load of structure.

Nonlinear response of a resonant viscoelastic microbeam under an electrical actuation

M. Zamanian,S.E. Khadem,S.N. Mahmoodi 국제구조공학회 2010 Structural Engineering and Mechanics, An Int'l Jou Vol.35 No.4

In this paper, using perturbation and Galerkin method, the response of a resonant viscoelastic microbeam to an electric actuation is obtained. The microbeam is under axial load and electrical load. It is assumed that midplane is stretched, when the beam is deflected. The equation of motion is derived using the Newton's second law. The viscoelastic model is taken to be the Kelvin-Voigt model. In the first section, the static deflection is obtained using the Galerkin method. Exact linear symmetric mode shape of a straight beam and its deflection function under constant transverse load are used as admissible functions. So, an analytical expression that describes the static deflection at all points is obtained. Comparing the result with previous research show that using deflection function as admissible function decreases the computation errors and previous calculations volume. In the second section, the response of a microbeam resonator system under primary and secondary resonance excitation has been obtained by analytical multiple scale perturbation method combined with the Galerkin method. It is shown, that a small amount of viscoelastic damping has an important effect and causes to decrease the maximum amplitude of response, and to shift the resonance frequency. Also, it shown, that an increase of the DC voltage, ratio of the air gap to the microbeam thickness, tensile axial load, would increase the effect of viscoelastic damping, and an increase of the compressive axial load would decrease the effect of viscoelastic damping.