subject:(Hyperelasticity)

Brno University of Technology

1. Burdík, Martin. Výpočtové modelování tlumiče rázů z plastických a hyperelastických materiálů: Computational models of shock absorbers of plastic and hyperelastic materials.

Degree: 2019, Brno University of Technology

URL: http://hdl.handle.net/11012/8769

► An aim of the given thesis is creating of a computational model of strain-stress behaviour of shock absorbers made of plastic and hyperelastic material. First… (more)

Subjects/Keywords: tlumič rázu; hyperelasticity; plasticity; Shock absorber; hyperelasticity; plasticity

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APA (6^th Edition):

Burdík, M. (2019). Výpočtové modelování tlumiče rázů z plastických a hyperelastických materiálů: Computational models of shock absorbers of plastic and hyperelastic materials. (Thesis). Brno University of Technology. Retrieved from http://hdl.handle.net/11012/8769

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Burdík, Martin. “Výpočtové modelování tlumiče rázů z plastických a hyperelastických materiálů: Computational models of shock absorbers of plastic and hyperelastic materials.” 2019. Thesis, Brno University of Technology. Accessed March 04, 2021. http://hdl.handle.net/11012/8769.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Burdík, Martin. “Výpočtové modelování tlumiče rázů z plastických a hyperelastických materiálů: Computational models of shock absorbers of plastic and hyperelastic materials.” 2019. Web. 04 Mar 2021.

Vancouver:

Burdík M. Výpočtové modelování tlumiče rázů z plastických a hyperelastických materiálů: Computational models of shock absorbers of plastic and hyperelastic materials. [Internet] [Thesis]. Brno University of Technology; 2019. [cited 2021 Mar 04]. Available from: http://hdl.handle.net/11012/8769.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Burdík M. Výpočtové modelování tlumiče rázů z plastických a hyperelastických materiálů: Computational models of shock absorbers of plastic and hyperelastic materials. [Thesis]. Brno University of Technology; 2019. Available from: http://hdl.handle.net/11012/8769

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

2. Chen, Zhuo-Wei. Simulation numérique du comportement dynamique des organes pelviens : Numerical simulation of dynamic behavior of pelvic organs.

Degree: Docteur es, Mécanique, 2013, Evry-Val d'Essonne

URL: http://www.theses.fr/2013EVRY0009

►

Le prolapsus des organes pelviens (vessie, rectum, utérus, vagin) est un problème de santé qui touche de plus en plus de femmes. Ce trouble, dont… (more)

▼

Le prolapsus des organes pelviens (vessie, rectum, utérus, vagin) est un problème de santé qui touche de plus en plus de femmes. Ce trouble, dont la fréquence augmente avec le vieillissement de la population, altère inévitablement la qualité de vie des malades. Pour autant, les causes de cette pathologie sont mal connues et les pratiques chirurgicales demeurent mal évaluées. La réalisation d’un simulateur du comportement dynamique des organes pelviens permettant au chirurgien d’estimer l’impact fonctionnel de son geste avant sa réalisation est donc un besoin identifié. Ce travail concerne ainsi le développement, par la méthode des éléments finis, d’un modèle numérique du mouvement des organes pelviens et de leurs interactions. Un modèle est construit à partir d’une segmentation de l’IRM des patiente, permettant de générer la géométrie des organes pelviens. Des lois hyperélastiques sont ensuite adoptées pour modéliser le comportement mécanique des organes. Des résultats qualitatifs sont obtenus, permettant de comprendre les causes de certaines formes de prolapsus et d’estimer l’effet virtuel des interactions entre les organes.

Pelvic organ prolapse is a health problem that occurs only in women and becomes more common. These disorders whose frequency increases with the aging of the population affect the patients’ quality of life. However, the causes of these diseases are poorly understood and the surgical practices remain poorly evaluated. The realization of a simulator will allow surgeon to estimate the functional impact of his actions before implementation, to perform the surgery in a more controlled and reliable way. This work concerns the development of a numerical model of pelvic organs’ movement and their interactions based on the finite element methods. A first model is constructed from patients MRI images, allowing the generation of the organ geometries. Hyperelastic modeling of the organs behaviors were considered. Qualitative results could help to understand the reasons for the prolapse and to estimate the potential effect of organs interactions.

Advisors/Committee Members: Feng, Zhi-Qiang (thesis director), Joli, Pierre (thesis director).

Subjects/Keywords: Hyperélasticité; Hyperelasticity; Pelvic organs; Soft tissue

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APA (6^th Edition):

Chen, Z. (2013). Simulation numérique du comportement dynamique des organes pelviens : Numerical simulation of dynamic behavior of pelvic organs. (Doctoral Dissertation). Evry-Val d'Essonne. Retrieved from http://www.theses.fr/2013EVRY0009

Chicago Manual of Style (16^th Edition):

Chen, Zhuo-Wei. “Simulation numérique du comportement dynamique des organes pelviens : Numerical simulation of dynamic behavior of pelvic organs.” 2013. Doctoral Dissertation, Evry-Val d'Essonne. Accessed March 04, 2021. http://www.theses.fr/2013EVRY0009.

MLA Handbook (7^th Edition):

Chen, Zhuo-Wei. “Simulation numérique du comportement dynamique des organes pelviens : Numerical simulation of dynamic behavior of pelvic organs.” 2013. Web. 04 Mar 2021.

Vancouver:

Chen Z. Simulation numérique du comportement dynamique des organes pelviens : Numerical simulation of dynamic behavior of pelvic organs. [Internet] [Doctoral dissertation]. Evry-Val d'Essonne; 2013. [cited 2021 Mar 04]. Available from: http://www.theses.fr/2013EVRY0009.

Council of Science Editors:

Chen Z. Simulation numérique du comportement dynamique des organes pelviens : Numerical simulation of dynamic behavior of pelvic organs. [Doctoral Dissertation]. Evry-Val d'Essonne; 2013. Available from: http://www.theses.fr/2013EVRY0009

George Mason University

3. Garrity, Michael J. Computational Membrane Model Using Finite Element Method for Flexible-Wing Based Micro Air Vehicles .

Degree: 2011, George Mason University

URL: http://hdl.handle.net/1920/6605

► Current designs for Micro Air Vehicles (MAVs) consist of a flexible wing with rigid battens for support. This paper analyzes the development and evaluation of… (more)

Subjects/Keywords: Membrane; MAV; Flexible; Hyperelasticity; Model; C++

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APA (6^th Edition):

Garrity, M. J. (2011). Computational Membrane Model Using Finite Element Method for Flexible-Wing Based Micro Air Vehicles . (Thesis). George Mason University. Retrieved from http://hdl.handle.net/1920/6605

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Garrity, Michael J. “Computational Membrane Model Using Finite Element Method for Flexible-Wing Based Micro Air Vehicles .” 2011. Thesis, George Mason University. Accessed March 04, 2021. http://hdl.handle.net/1920/6605.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Garrity, Michael J. “Computational Membrane Model Using Finite Element Method for Flexible-Wing Based Micro Air Vehicles .” 2011. Web. 04 Mar 2021.

Vancouver:

Garrity MJ. Computational Membrane Model Using Finite Element Method for Flexible-Wing Based Micro Air Vehicles . [Internet] [Thesis]. George Mason University; 2011. [cited 2021 Mar 04]. Available from: http://hdl.handle.net/1920/6605.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Garrity MJ. Computational Membrane Model Using Finite Element Method for Flexible-Wing Based Micro Air Vehicles . [Thesis]. George Mason University; 2011. Available from: http://hdl.handle.net/1920/6605

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Indian Institute of Science

4. Patil, Kunal D. Geometric And Material Stability Criteria For Material Models In Hyperelasticity.

Degree: MSc Engg, Faculty of Engineering, 2013, Indian Institute of Science

URL: http://etd.iisc.ac.in/handle/2005/2120

► In the literature, there are various material models proposed so as to model the constitutive behavior of hyperelastic materials for example, St. Venant-Kirchho_ model, Mooney-Rivlin… (more)

Subjects/Keywords: Hyperelasticity; Deformation Theory; Material Instability; Finite Deformation; Hyperelasticity - Material Models; Material Models; Geometric Instability; Finite Deformation Theory; Hyperelastic Materials; Materials Science

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APA (6^th Edition):

Patil, K. D. (2013). Geometric And Material Stability Criteria For Material Models In Hyperelasticity. (Masters Thesis). Indian Institute of Science. Retrieved from http://etd.iisc.ac.in/handle/2005/2120

Chicago Manual of Style (16^th Edition):

Patil, Kunal D. “Geometric And Material Stability Criteria For Material Models In Hyperelasticity.” 2013. Masters Thesis, Indian Institute of Science. Accessed March 04, 2021. http://etd.iisc.ac.in/handle/2005/2120.

MLA Handbook (7^th Edition):

Patil, Kunal D. “Geometric And Material Stability Criteria For Material Models In Hyperelasticity.” 2013. Web. 04 Mar 2021.

Vancouver:

Patil KD. Geometric And Material Stability Criteria For Material Models In Hyperelasticity. [Internet] [Masters thesis]. Indian Institute of Science; 2013. [cited 2021 Mar 04]. Available from: http://etd.iisc.ac.in/handle/2005/2120.

Council of Science Editors:

Patil KD. Geometric And Material Stability Criteria For Material Models In Hyperelasticity. [Masters Thesis]. Indian Institute of Science; 2013. Available from: http://etd.iisc.ac.in/handle/2005/2120

University of Saskatchewan

5. St. Jean, Simon. Applications of symmetries and conservation laws to the study of nonlinear elasticity equations.

Degree: 2014, University of Saskatchewan

URL: http://hdl.handle.net/10388/ETD-2015-05-1773

► Mooney-Rivlin hyperelasticity equations are nonlinear coupled partial differential equations (PDEs) that are used to model various elastic materials. These models have been extended to account… (more)

Subjects/Keywords: Applied Mathematics; Conservation Law; Differential Equations; Elasticity; Hyperelasticity; Lie Symmetry Analysis

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APA (6^th Edition):

St. Jean, S. (2014). Applications of symmetries and conservation laws to the study of nonlinear elasticity equations. (Thesis). University of Saskatchewan. Retrieved from http://hdl.handle.net/10388/ETD-2015-05-1773

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

St. Jean, Simon. “Applications of symmetries and conservation laws to the study of nonlinear elasticity equations.” 2014. Thesis, University of Saskatchewan. Accessed March 04, 2021. http://hdl.handle.net/10388/ETD-2015-05-1773.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

St. Jean, Simon. “Applications of symmetries and conservation laws to the study of nonlinear elasticity equations.” 2014. Web. 04 Mar 2021.

Vancouver:

St. Jean S. Applications of symmetries and conservation laws to the study of nonlinear elasticity equations. [Internet] [Thesis]. University of Saskatchewan; 2014. [cited 2021 Mar 04]. Available from: http://hdl.handle.net/10388/ETD-2015-05-1773.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

St. Jean S. Applications of symmetries and conservation laws to the study of nonlinear elasticity equations. [Thesis]. University of Saskatchewan; 2014. Available from: http://hdl.handle.net/10388/ETD-2015-05-1773

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Western Ontario

6. Sheikh Bagher Mohajer, Mohammad Mahdi. Wave Propagation in Viscoelastic Dielectric Elastomer Media.

Degree: 2020, University of Western Ontario

URL: https://ir.lib.uwo.ca/etd/6847

► Dielectric elastomers (DEs) are capable of producing large deformation under electric stimuli, which makes them desirable materials for a variety of applications including biomimetics, dynamics,… (more)

Subjects/Keywords: Rayleigh-Lamb wave; Electroelastic wave; Waveguide; Dielectric elastomers; viscoelasticity; hyperelasticity

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APA (6^th Edition):

Sheikh Bagher Mohajer, M. M. (2020). Wave Propagation in Viscoelastic Dielectric Elastomer Media. (Thesis). University of Western Ontario. Retrieved from https://ir.lib.uwo.ca/etd/6847

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Sheikh Bagher Mohajer, Mohammad Mahdi. “Wave Propagation in Viscoelastic Dielectric Elastomer Media.” 2020. Thesis, University of Western Ontario. Accessed March 04, 2021. https://ir.lib.uwo.ca/etd/6847.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Sheikh Bagher Mohajer, Mohammad Mahdi. “Wave Propagation in Viscoelastic Dielectric Elastomer Media.” 2020. Web. 04 Mar 2021.

Vancouver:

Sheikh Bagher Mohajer MM. Wave Propagation in Viscoelastic Dielectric Elastomer Media. [Internet] [Thesis]. University of Western Ontario; 2020. [cited 2021 Mar 04]. Available from: https://ir.lib.uwo.ca/etd/6847.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Sheikh Bagher Mohajer MM. Wave Propagation in Viscoelastic Dielectric Elastomer Media. [Thesis]. University of Western Ontario; 2020. Available from: https://ir.lib.uwo.ca/etd/6847

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Western Ontario

7. Gillani, Asim. Development Of Material Model Subroutines For Linear And Nonlinear Response Of Elastomers.

Degree: 2018, University of Western Ontario

URL: https://ir.lib.uwo.ca/etd/5837

► The nature of elastomers has been extensively studied ever since the vulcanization of rubber in the 19th century. Elastomers have been heavily employed in various… (more)

Subjects/Keywords: Elastomers; Viscoelasticity; hyperelasticity; user material subroutines; finite element simulation.; Applied Mechanics

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APA (6^th Edition):

Gillani, A. (2018). Development Of Material Model Subroutines For Linear And Nonlinear Response Of Elastomers. (Thesis). University of Western Ontario. Retrieved from https://ir.lib.uwo.ca/etd/5837

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Gillani, Asim. “Development Of Material Model Subroutines For Linear And Nonlinear Response Of Elastomers.” 2018. Thesis, University of Western Ontario. Accessed March 04, 2021. https://ir.lib.uwo.ca/etd/5837.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Gillani, Asim. “Development Of Material Model Subroutines For Linear And Nonlinear Response Of Elastomers.” 2018. Web. 04 Mar 2021.

Vancouver:

Gillani A. Development Of Material Model Subroutines For Linear And Nonlinear Response Of Elastomers. [Internet] [Thesis]. University of Western Ontario; 2018. [cited 2021 Mar 04]. Available from: https://ir.lib.uwo.ca/etd/5837.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Gillani A. Development Of Material Model Subroutines For Linear And Nonlinear Response Of Elastomers. [Thesis]. University of Western Ontario; 2018. Available from: https://ir.lib.uwo.ca/etd/5837

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Brno University of Technology

8. Mucha, Petr. Deformačně-napěťová analýza výdutí tepen: Stress-strain analysis of aneurysms of arteries.

Degree: 2019, Brno University of Technology

URL: http://hdl.handle.net/11012/25201

► This diploma thesis deals with the creation of computational model of arterial aneurysm, which respects its real geometry and constitutive behaviour. Subsequently there is explored… (more)

Subjects/Keywords: hyperelasticita; arteriální výduť; redukovaná geometrie; hyperelasticity; arterial aneurysm; reduced geometry

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APA (6^th Edition):

Mucha, P. (2019). Deformačně-napěťová analýza výdutí tepen: Stress-strain analysis of aneurysms of arteries. (Thesis). Brno University of Technology. Retrieved from http://hdl.handle.net/11012/25201

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Mucha, Petr. “Deformačně-napěťová analýza výdutí tepen: Stress-strain analysis of aneurysms of arteries.” 2019. Thesis, Brno University of Technology. Accessed March 04, 2021. http://hdl.handle.net/11012/25201.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Mucha, Petr. “Deformačně-napěťová analýza výdutí tepen: Stress-strain analysis of aneurysms of arteries.” 2019. Web. 04 Mar 2021.

Vancouver:

Mucha P. Deformačně-napěťová analýza výdutí tepen: Stress-strain analysis of aneurysms of arteries. [Internet] [Thesis]. Brno University of Technology; 2019. [cited 2021 Mar 04]. Available from: http://hdl.handle.net/11012/25201.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Mucha P. Deformačně-napěťová analýza výdutí tepen: Stress-strain analysis of aneurysms of arteries. [Thesis]. Brno University of Technology; 2019. Available from: http://hdl.handle.net/11012/25201

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Duke University

9. abboud, nabil. A Class of Tetrahedral Finite Elements for Complex Geometry and Nonlinear Mechanics: A Variational Multiscale Approach .

Degree: 2019, Duke University

URL: http://hdl.handle.net/10161/20117

► In this work, a stabilized finite element framework is developed to simulate small and large deformation solid mechanics problems involving complex geometries and complicated… (more)

▼ In this work, a stabilized finite element framework is developed to simulate small and large deformation solid mechanics problems involving complex geometries and complicated constitutive models. In particular, the focus is on solid dynamics problems involving nearly and fully incompressible materials. The work is divided into three main themes, the first is concerned with the development of stabilized finite element algorithms for hyperelastic materials, the second handles the case of viscoelastic materials, and the third focuses on algorithms for J2-plastic materials. For all three cases, problems in the small and large deformation regime are considered, and for the J2-plasticity case, both quasi-static and dynamic problems are examined. Some of the key features of the algorithms developed in this work is the simplicity of their implementation into an existing finite element code, and their applicability to problems involving complicated geometries. The former is achieved by using a mixed formulation of the solid mechanics equations where the velocity and pressure unknowns are represented by linear shape functions, whereas the latter is realized by using triangular elements which offer numerous advantages compared to quadrilaterals, when meshing complicated geometries. To achieve the stability of the algorithm, a new approach is proposed in which the variational multiscale approach is applied to the mixed form of the solid mechanics equations written down as a first order system, whereby the pressure equation is cast in rate form. Through a series of numerical simulations, it is shown that the stability properties of the proposed algorithm is invariant to the constitutive model and the time integrator used. By running convergence tests, the algorithm is shown to be second order accurate, in the L²-nrom, for the displacements, velocities, and pressure. Finally, the robustness of the algorithm is showcased by considering realistic test cases involving complicated geometries and very large deformation. Advisors/Committee Members: Scovazzi, Guglielmo (advisor).

Subjects/Keywords: Applied mathematics; Finite Elements; Hyperelasticity; Plasticity; Stabilization; Variational Multiscale; Viscoelasticity

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APA (6^th Edition):

abboud, n. (2019). A Class of Tetrahedral Finite Elements for Complex Geometry and Nonlinear Mechanics: A Variational Multiscale Approach . (Thesis). Duke University. Retrieved from http://hdl.handle.net/10161/20117

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

abboud, nabil. “A Class of Tetrahedral Finite Elements for Complex Geometry and Nonlinear Mechanics: A Variational Multiscale Approach .” 2019. Thesis, Duke University. Accessed March 04, 2021. http://hdl.handle.net/10161/20117.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

abboud, nabil. “A Class of Tetrahedral Finite Elements for Complex Geometry and Nonlinear Mechanics: A Variational Multiscale Approach .” 2019. Web. 04 Mar 2021.

Vancouver:

abboud n. A Class of Tetrahedral Finite Elements for Complex Geometry and Nonlinear Mechanics: A Variational Multiscale Approach . [Internet] [Thesis]. Duke University; 2019. [cited 2021 Mar 04]. Available from: http://hdl.handle.net/10161/20117.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

abboud n. A Class of Tetrahedral Finite Elements for Complex Geometry and Nonlinear Mechanics: A Variational Multiscale Approach . [Thesis]. Duke University; 2019. Available from: http://hdl.handle.net/10161/20117

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Louisiana State University

10. Samadidooki, Aref. Experimental, Analytical, and Numerical Evaluation of the Mechanical Properties of the Brain Tissue.

Degree: PhD, Applied Mechanics, 2018, Louisiana State University

URL: https://digitalcommons.lsu.edu/gradschool_dissertations/4622

► A true understanding of the mechanisms behind most of the brain diseases is still out of reach. For several years, the interest of scientists… (more)

▼ A true understanding of the mechanisms behind most of the brain diseases is still out of reach. For several years, the interest of scientists has been focused on the genetic and biological causes, however, recent studies unraveled the importance of the biomechanics of the brain growth, folding, impact resistance, and deformation on its pathological conditions. While, a wide range of different methods have been used for characterization of the mechanical properties of the brain at the tissue level, the obtained results from different studies are extremely scattered and sometimes in contrast to one another. Since the brain tissue is extremely soft, its mechanical properties are quite a challenge to be obtained. In this study, the accurate analysis of the mechanical heterogeneity of the brain tissue is performed through dynamic and pseudo-static indentation techniques to evaluate the viscoelastic response of the brain and presenting its anisotropy, inhomogeneity, and rate dependence. In addition, this research provides a detailed reference for modeling the nonlinear mechanical behavior of soft tissues, in general, and the brain tissue, in particular, with addressing important considerations for mechanical modeling in uniaxial loading conditions. With thoroughly presenting the physical basis of the modeling procedure, it is shown that if such considerations are neglected, a considerable inaccurate evaluation of the mechanical properties of the tissue can be expected, although the results might mathematically be correct. Moreover, a new model is developed for the mechanical behavior of the brain tissue that addresses the tension-compression asymmetry with taking into account the compressibility of the tissue in different loading conditions. This model is implemented by utilizing a combined analytical and numerical scheme. The results of this research could be used as input variables for computer simulations of the brain tissue in studying the traumatic brain injury, malformation of the brain folds, and other pathobiological conditions associated with the mechanical behavior of the brain.

Subjects/Keywords: Brain Biomechanics; Indirect Indentation; Viscoelasticity; Hyperelasticity; Finite Element Modeling

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APA (6^th Edition):

Samadidooki, A. (2018). Experimental, Analytical, and Numerical Evaluation of the Mechanical Properties of the Brain Tissue. (Doctoral Dissertation). Louisiana State University. Retrieved from https://digitalcommons.lsu.edu/gradschool_dissertations/4622

Chicago Manual of Style (16^th Edition):

Samadidooki, Aref. “Experimental, Analytical, and Numerical Evaluation of the Mechanical Properties of the Brain Tissue.” 2018. Doctoral Dissertation, Louisiana State University. Accessed March 04, 2021. https://digitalcommons.lsu.edu/gradschool_dissertations/4622.

MLA Handbook (7^th Edition):

Samadidooki, Aref. “Experimental, Analytical, and Numerical Evaluation of the Mechanical Properties of the Brain Tissue.” 2018. Web. 04 Mar 2021.

Vancouver:

Samadidooki A. Experimental, Analytical, and Numerical Evaluation of the Mechanical Properties of the Brain Tissue. [Internet] [Doctoral dissertation]. Louisiana State University; 2018. [cited 2021 Mar 04]. Available from: https://digitalcommons.lsu.edu/gradschool_dissertations/4622.

Council of Science Editors:

Samadidooki A. Experimental, Analytical, and Numerical Evaluation of the Mechanical Properties of the Brain Tissue. [Doctoral Dissertation]. Louisiana State University; 2018. Available from: https://digitalcommons.lsu.edu/gradschool_dissertations/4622

11. Ferranto, Justin S. Material and Geometric Analysis of Structures Subjected to Large Deformation.

Degree: 2016, University of Nevada – Reno

URL: http://hdl.handle.net/11714/2285

► The two major focuses of this dissertation are: (1) Studying the structural behaviors of hyper-elastic membranes subjected to extremely large deformation. These membranes are used… (more)

▼ The two major focuses of this dissertation are: (1) Studying the structural behaviors of hyper-elastic membranes subjected to extremely large deformation. These membranes are used in a reconfigurable tooling system (RTS) which was under development during the course of this study. (2) Establishing a continuum constitutive model for fabric materials under in-plane large deformation through theoretical and numerical analyses. This model may also be applied to study a class of materials which involve significant internal structure reconfiguration during deformation.The RTS allows quick onsite fabrication of high temperature composite parts. RTS applications include rapid onsite repair of aircraft components. The RTS uses a hyperelastic membrane as an interface between the state-change material and model. This membrane may be subjected to 800% engineering strain during operation. In this part of the study, material properties of the membranes have been characterized through three tests: simple tension, equal biaxial tension and planar tension. Nine-term Money-Rivlin constants are obtained through data regression. Finite element simulations have been conducted to simulate the deformed shapes of a membrane around several representative geometries under various vacuum pressure and constraint conditions. Experimental results have been compared with predictions from finite element simulations. This study contributes to understanding the behavior of membrane structures under large deformations in general; the results are used to generate design guidelines for RTS applicability.Fabric materials are widely used in industry for numerous applications. They exhibit a meso-scale complexity and involve significant internal structure reconfiguration during large deformation, which prohibits the direct application of the theory of continuum mechanics when studying these materials. In the second part of this work, a unique meso-scale FEA model, utilizing new modeling techniques and boundary conditions, is developed. This model can be used to simulate the weaving/loom process, and to predict the mechanical behaviors of a representative unit of fabric subjected to multi-axial large deformations. This model has also been used to examine the mechanism of fabric internal structure reconfiguration during deformation under various load paths. An energy based continuum model for plain weave fabric is developed, where a sinusoidal shape function is used to describe the yarn waviness before and after deformation. Castigliano's theorem is applied to determine the interactions between yarns. The model presented has been validated with the FEA model, and compared with third party experiments. Favorable agreements have been found. This model has the potential for developing a general constitutive relationship for a broad class of materials which involve significant internal structure reconfiguration during deformation Advisors/Committee Members: Shan, Wanliang (advisor), Luo, Shen-Yi (advisor), Gibson, Ronald (committee member), Liao, Yiliang (committee member), Upadhyay, Arun (committee member), Shan, Wanliang (committee member), Luo, Shen-Yi (committee member).

Subjects/Keywords: Fabric; Hyperelasticity; Large Deformation; Mooney-Rivlin; Plain Weave; Textile

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APA (6^th Edition):

Ferranto, J. S. (2016). Material and Geometric Analysis of Structures Subjected to Large Deformation. (Thesis). University of Nevada – Reno. Retrieved from http://hdl.handle.net/11714/2285

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Ferranto, Justin S. “Material and Geometric Analysis of Structures Subjected to Large Deformation.” 2016. Thesis, University of Nevada – Reno. Accessed March 04, 2021. http://hdl.handle.net/11714/2285.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Ferranto, Justin S. “Material and Geometric Analysis of Structures Subjected to Large Deformation.” 2016. Web. 04 Mar 2021.

Vancouver:

Ferranto JS. Material and Geometric Analysis of Structures Subjected to Large Deformation. [Internet] [Thesis]. University of Nevada – Reno; 2016. [cited 2021 Mar 04]. Available from: http://hdl.handle.net/11714/2285.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Ferranto JS. Material and Geometric Analysis of Structures Subjected to Large Deformation. [Thesis]. University of Nevada – Reno; 2016. Available from: http://hdl.handle.net/11714/2285

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Duke University

12. abboud, nabil. A Class of Tetrahedral Finite Elements for Complex Geometry and Nonlinear Mechanics: A Variational Multiscale Approach .

Degree: 2019, Duke University

URL: http://hdl.handle.net/10161/22076

► In this work, a stabilized finite element framework is developed to simulate small and large deformation solid mechanics problems involving complex geometries and complicated… (more)

▼ In this work, a stabilized finite element framework is developed to simulate small and large deformation solid mechanics problems involving complex geometries and complicated constitutive models. In particular, the focus is on solid dynamics problems involving nearly and fully incompressible materials. The work is divided into three main themes, the first is concerned with the development of stabilized finite element algorithms for hyperelastic materials, the second handles the case of viscoelastic materials, and the third focuses on algorithms for J2-plastic materials. For all three cases, problems in the small and large deformation regime are considered, and for the J2-plasticity case, both quasi-static and dynamic problems are examined. Some of the key features of the algorithms developed in this work is the simplicity of their implementation into an existing finite element code, and their applicability to problems involving complicated geometries. The former is achieved by using a mixed formulation of the solid mechanics equations where the velocity and pressure unknowns are represented by linear shape functions, whereas the latter is realized by using triangular elements which offer numerous advantages compared to quadrilaterals, when meshing complicated geometries. To achieve the stability of the algorithm, a new approach is proposed in which the variational multiscale approach is applied to the mixed form of the solid mechanics equations written down as a first order system, whereby the pressure equation is cast in rate form. Through a series of numerical simulations, it is shown that the stability properties of the proposed algorithm is invariant to the constitutive model and the time integrator used. By running convergence tests, the algorithm is shown to be second order accurate, in the L²-nrom, for the displacements, velocities, and pressure. Finally, the robustness of the algorithm is showcased by considering realistic test cases involving complicated geometries and very large deformation. Advisors/Committee Members: Scovazzi, Guglielmo (advisor).

Subjects/Keywords: Applied mathematics; Finite Elements; Hyperelasticity; Plasticity; Stabilization; Variational Multiscale; Viscoelasticity

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

abboud, n. (2019). A Class of Tetrahedral Finite Elements for Complex Geometry and Nonlinear Mechanics: A Variational Multiscale Approach . (Thesis). Duke University. Retrieved from http://hdl.handle.net/10161/22076

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

abboud, nabil. “A Class of Tetrahedral Finite Elements for Complex Geometry and Nonlinear Mechanics: A Variational Multiscale Approach .” 2019. Thesis, Duke University. Accessed March 04, 2021. http://hdl.handle.net/10161/22076.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

abboud, nabil. “A Class of Tetrahedral Finite Elements for Complex Geometry and Nonlinear Mechanics: A Variational Multiscale Approach .” 2019. Web. 04 Mar 2021.

Vancouver:

abboud n. A Class of Tetrahedral Finite Elements for Complex Geometry and Nonlinear Mechanics: A Variational Multiscale Approach . [Internet] [Thesis]. Duke University; 2019. [cited 2021 Mar 04]. Available from: http://hdl.handle.net/10161/22076.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

abboud n. A Class of Tetrahedral Finite Elements for Complex Geometry and Nonlinear Mechanics: A Variational Multiscale Approach . [Thesis]. Duke University; 2019. Available from: http://hdl.handle.net/10161/22076

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

13. Wheatley, Benjamin Brandt. Finite element analysis of skeletal muscle: a validated approach to modeling muscle force and intramuscular pressure.

Degree: PhD, Mechanical Engineering, 2017, Colorado State University

URL: http://hdl.handle.net/10217/181381

► Impaired muscle function can such as weakness is a reduction in muscle quality or quantity. Muscle weakness is debilitating conditions which can result from neuromuscular… (more)

▼ Impaired muscle function can such as weakness is a reduction in muscle quality or quantity. Muscle weakness is debilitating conditions which can result from neuromuscular diseases and conditions such as multiple sclerosis, muscular dystrophy, stroke, injury, and aging. Impaired muscle function leads to disability, risk of injury, decreases in quality of life, and even death. Early disease detection, rehabilitation efforts, surgical techniques, and drug delivery can all be improved with the ability to identify muscle weakness by determining individual muscle force in vivo. Current clinical methods fail to measure individual muscle force as they are either inaccurate for individual muscle estimations (torque measurements) or are too invasive (buckle transducer insertion). Electromyography (EMG) is commonly used to diagnose improper muscle function, yet it is only a measurement of electrical activity. Thus, there is no minimally invasive clinical method which currently evaluates muscle force in vivo, which makes identifying and treating impaired muscle a challenge. Pressure of interstitial fluid within muscle (i.e. Intramuscular Pressure, IMP) is the direct result of active muscle contraction or passive stretch. A low profile pressure microsensor can be used to measure IMP and thus evaluate force of individual muscles in vivo. Accurate microsensor use however, is reliant upon developing a relationship between IMP and force, which is currently incomplete. Specifically, while force and IMP are correlated, the variability of IMP in vivo makes muscle force estimates from IMP measurements a challenge. Additionally, the distribution of IMP throughout muscle is variable and poorly understood. The goal of this work is to develop a computational model which can be used to better understand the behavior of intramuscular pressure. However, a lack of mechanical experimental analysis of skeletal muscle makes developing a robust model a challenge. Thus, two specific aims are proposed: 1) Experimentally investigate the passive properties of skeletal muscle and identify proper modeling assumptions to make in developing a constitutive approach. 2) Develop and implement a finite element approach for skeletal muscle which is capable of simulating muscle force and intramuscular pressure under passive stretch and active contraction conditions. Implementation of this model will provide insight into the potential causes of variability of intramuscular pressure measurements in vivo and future clinical approaches. Advisors/Committee Members: Haut Donahue, Tammy L. (advisor), Browning, Raymond C. (committee member), Kaufman, Kenton R. (committee member), Puttlitz, Christian M. (committee member).

Subjects/Keywords: constitutive modeling; muscle weakness; viscoelasticity; hyperelasticity; computational modeling; poroelasticity

10 more images…

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APA (6^th Edition):

Wheatley, B. B. (2017). Finite element analysis of skeletal muscle: a validated approach to modeling muscle force and intramuscular pressure. (Doctoral Dissertation). Colorado State University. Retrieved from http://hdl.handle.net/10217/181381

Chicago Manual of Style (16^th Edition):

Wheatley, Benjamin Brandt. “Finite element analysis of skeletal muscle: a validated approach to modeling muscle force and intramuscular pressure.” 2017. Doctoral Dissertation, Colorado State University. Accessed March 04, 2021. http://hdl.handle.net/10217/181381.

MLA Handbook (7^th Edition):

Wheatley, Benjamin Brandt. “Finite element analysis of skeletal muscle: a validated approach to modeling muscle force and intramuscular pressure.” 2017. Web. 04 Mar 2021.

Vancouver:

Wheatley BB. Finite element analysis of skeletal muscle: a validated approach to modeling muscle force and intramuscular pressure. [Internet] [Doctoral dissertation]. Colorado State University; 2017. [cited 2021 Mar 04]. Available from: http://hdl.handle.net/10217/181381.

Council of Science Editors:

Wheatley BB. Finite element analysis of skeletal muscle: a validated approach to modeling muscle force and intramuscular pressure. [Doctoral Dissertation]. Colorado State University; 2017. Available from: http://hdl.handle.net/10217/181381

Universidade do Rio Grande do Sul

14. Wrubleski, Eduardo Guilherme Mötke. Inclusão de efeitos dissipativos em modelos constitutivos hiperelásticos através da modificação da função energia de deformação.

Degree: 2015, Universidade do Rio Grande do Sul

URL: http://hdl.handle.net/10183/114972

►

Este trabalho apresenta uma metodologia para a inclusão de fenômenos dissipativos em relações constitutivas hiperelásticas. Embora seja dada ênfase para o efeito Mullins e histerese,… (more)

▼

Este trabalho apresenta uma metodologia para a inclusão de fenômenos dissipativos em relações constitutivas hiperelásticas. Embora seja dada ênfase para o efeito Mullins e histerese, esse procedimento pode ser aplicado a outros fenômenos como, por exemplo, de dano. Para isso, adota-se um modelo fenomenológico que inclui amolecimento em um modelo constitutivo hiperelástico através da pseudo-elasticidade, que permite que diferentes potenciais de energia possam ser utilizados em diferentes etapas do carregamento. Foram utilizados dois modelos hiperelásticos incompressíveis: Ogden e Hoss-Marczak. Para esse estudo, foram selecionados quatro diferentes materiais da literatura, três deles apresentavam apenas dados experimentais para tração uniaxial, enquanto o outro disponibilizou os ensaios de tração uniaxial, tração equibiaxial e cisalhamento puro. Foram selecionados dois parâmetros de amolecimento da literatura (Ogden e Roxburgh, 1999, e Dorfmann e Ogden, 2003) para modelar fenômenos dissipativos e então foram propostos novos parâmetros de amolecimento. Verificação gráfica dos resultados e um coeficiente de correlação (R2) foram utilizados para comparar o desempenho desses parâmetros. Os materiais foram considerados isotrópicos e incompressíveis e o carregamento quasi-estático para obtenção dos resultados. Alguns parâmetros propostos não capturaram o efeito dissipativo, outros superestimaram o amolecimento, enquanto os da literatura capturaram o efeito. Ao final, obteve-se resultados bastante satisfatórios para um dos parâmetros propostos, que se verificou ser uma generalização do modelo de Dorfmann e Ogden, 2003.

This work applies a methodology to include dissipative effects in hyperelastic constitutive relations. The paper focuses on the Mullins effect and hysteresis. However, the methodology can also be applied to other phenomena, like damage. Basically, it is a phenomenological inclusion of the softening behavior in a hyperelastic constitutive model using pseudo-elasticity, in which different energy potentials can be used in different steps of the loading. Two hyperelastic models were employed: Ogden’s and Hoss-Marczak’s models. Four different materials were modeled, three of them subjected to uniaxial tension only, and a fourth subjected to the three classical loadings, namely, uniaxial tension, equibiaxial tension and pure shear. Two softening parameters from the literature were implemented and new softening parameters were proposed. Graphical inspection and R2 correlation coefficient were used to compare the softening parameters. The materials were considered isotropic and incompressible, being subjected to quasi-static loading. Some of the proposed parameters did not captured the dissipative effect, other overestimate the softening, and those from the literature were able to capture the effects. Finally, very satisfying results were obtained with one the proposed softening parameters, which was a generalization of the one proposed by Dorfmann e Ogden, 2003.

Advisors/Committee Members: Marczak, Rogerio Jose.

Subjects/Keywords: Pseudo-elasticity; Elasticidade; Ensaios de tração; Hyperelasticity; Histerese; Mulins effect; Hysteresis; Constitutive models

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Wrubleski, E. G. M. (2015). Inclusão de efeitos dissipativos em modelos constitutivos hiperelásticos através da modificação da função energia de deformação. (Thesis). Universidade do Rio Grande do Sul. Retrieved from http://hdl.handle.net/10183/114972

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Wrubleski, Eduardo Guilherme Mötke. “Inclusão de efeitos dissipativos em modelos constitutivos hiperelásticos através da modificação da função energia de deformação.” 2015. Thesis, Universidade do Rio Grande do Sul. Accessed March 04, 2021. http://hdl.handle.net/10183/114972.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Wrubleski, Eduardo Guilherme Mötke. “Inclusão de efeitos dissipativos em modelos constitutivos hiperelásticos através da modificação da função energia de deformação.” 2015. Web. 04 Mar 2021.

Vancouver:

Wrubleski EGM. Inclusão de efeitos dissipativos em modelos constitutivos hiperelásticos através da modificação da função energia de deformação. [Internet] [Thesis]. Universidade do Rio Grande do Sul; 2015. [cited 2021 Mar 04]. Available from: http://hdl.handle.net/10183/114972.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Wrubleski EGM. Inclusão de efeitos dissipativos em modelos constitutivos hiperelásticos através da modificação da função energia de deformação. [Thesis]. Universidade do Rio Grande do Sul; 2015. Available from: http://hdl.handle.net/10183/114972

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

15. Bang, Dongjun. Peridynamic Modeling of Hyperelastic Materials .

Degree: 2016, University of Arizona

URL: http://hdl.handle.net/10150/595809

► This study concerns the development of the peridynamic strain energy density function for a Neo-Hookean type membrane under equibiaxial, planar and uniaxial loading conditions. The… (more)

Subjects/Keywords: hyperelasticity; peridynamics; Mechanical Engineering; deformation

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Bang, D. (2016). Peridynamic Modeling of Hyperelastic Materials . (Doctoral Dissertation). University of Arizona. Retrieved from http://hdl.handle.net/10150/595809

Chicago Manual of Style (16^th Edition):

Bang, Dongjun. “Peridynamic Modeling of Hyperelastic Materials .” 2016. Doctoral Dissertation, University of Arizona. Accessed March 04, 2021. http://hdl.handle.net/10150/595809.

MLA Handbook (7^th Edition):

Bang, Dongjun. “Peridynamic Modeling of Hyperelastic Materials .” 2016. Web. 04 Mar 2021.

Vancouver:

Bang D. Peridynamic Modeling of Hyperelastic Materials . [Internet] [Doctoral dissertation]. University of Arizona; 2016. [cited 2021 Mar 04]. Available from: http://hdl.handle.net/10150/595809.

Council of Science Editors:

Bang D. Peridynamic Modeling of Hyperelastic Materials . [Doctoral Dissertation]. University of Arizona; 2016. Available from: http://hdl.handle.net/10150/595809

Rochester Institute of Technology

16. Lillie, Jeffrey S. Development, Validation, and Clinical Application of a Numerical Model for Pulse Wave Velocity Propagation in a Cardiovascular System with Application to Noninvasive Blood Pressure Measurements.

Degree: PhD, Microsystems Engineering, 2017, Rochester Institute of Technology

URL: https://scholarworks.rit.edu/theses/9379

► High blood pressure blood pressure is an important risk factor for cardiovascular disease and affects almost one-third of the U.S. adult population. Historical cuff-less… (more)

▼ High blood pressure blood pressure is an important risk factor for cardiovascular disease and affects almost one-third of the U.S. adult population. Historical cuff-less non-invasive techniques used to monitor blood pressure are not accurate and highlight the need for first principal models. The first model is a one-dimensional model for pulse wave velocity (PWV) propagation in compliant arteries that accounts for nonlinear fluids in a linear elastic thin walled vessel. The results indicate an inverse quadratic relationship (R²=.99) between ejection time and PWV, with ejection time dominating the PWV shifts (12%). The second model predicts the general relationship between PWV and blood pressure with a rigorous account of nonlinearities in the fluid dynamics, blood vessel elasticity, and finite dynamic deformation of a membrane type thin anisotropic wall. The nonlinear model achieves the best match with the experimental data. To retrieve individual vascular information of a patient, the inverse problem of hemodynamics is presented, calculating local orthotropic hyperelastic properties of the arterial wall. The final model examines the impact of the thick arterial wall with different material properties in the radial direction. For a hypertensive subject the thick wall model provides improved accuracy up to 8.4% in PWV prediction over its thin wall counterpart. This translates to nearly 20% improvement in blood pressure prediction based on a PWV measure. The models highlight flow velocity is additive to the classic pressure wave, suggesting flow velocity correction may be important for cuff-less, non-invasive blood pressure measures. Systolic flow correction of the measured PWV improves the R2 correlation to systolic blood pressure from 0.81 to 0.92 for the mongrel dog study, and 0.34 to 0.88 for the human subjects study. The algorithms and insight resulting from this work can enable the development of an integrated microsystem for cuff-less, non-invasive blood pressure monitoring. Advisors/Committee Members: David A. Borkholder.

Subjects/Keywords: Blood pressure; Convective fluid; Finite deformation; Hyperelasticity; Nonlinear 1D model; Pulse wave velocity

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Lillie, J. S. (2017). Development, Validation, and Clinical Application of a Numerical Model for Pulse Wave Velocity Propagation in a Cardiovascular System with Application to Noninvasive Blood Pressure Measurements. (Doctoral Dissertation). Rochester Institute of Technology. Retrieved from https://scholarworks.rit.edu/theses/9379

Chicago Manual of Style (16^th Edition):

Lillie, Jeffrey S. “Development, Validation, and Clinical Application of a Numerical Model for Pulse Wave Velocity Propagation in a Cardiovascular System with Application to Noninvasive Blood Pressure Measurements.” 2017. Doctoral Dissertation, Rochester Institute of Technology. Accessed March 04, 2021. https://scholarworks.rit.edu/theses/9379.

MLA Handbook (7^th Edition):

Lillie, Jeffrey S. “Development, Validation, and Clinical Application of a Numerical Model for Pulse Wave Velocity Propagation in a Cardiovascular System with Application to Noninvasive Blood Pressure Measurements.” 2017. Web. 04 Mar 2021.

Vancouver:

Lillie JS. Development, Validation, and Clinical Application of a Numerical Model for Pulse Wave Velocity Propagation in a Cardiovascular System with Application to Noninvasive Blood Pressure Measurements. [Internet] [Doctoral dissertation]. Rochester Institute of Technology; 2017. [cited 2021 Mar 04]. Available from: https://scholarworks.rit.edu/theses/9379.

Council of Science Editors:

Lillie JS. Development, Validation, and Clinical Application of a Numerical Model for Pulse Wave Velocity Propagation in a Cardiovascular System with Application to Noninvasive Blood Pressure Measurements. [Doctoral Dissertation]. Rochester Institute of Technology; 2017. Available from: https://scholarworks.rit.edu/theses/9379

17. Oueslati, Zied. Modèle de comportement pour la modélisation du thermoformage de feuilles plastiques multicouches : Constitutive law for modeling multilayered thermplastic sheets thermoforming.

Degree: Docteur es, Mécanique Avancée, 2015, Compiègne

URL: http://www.theses.fr/2015COMP2213

►

Les Thermoplastique Polyoléfine (TPO) se sont avérés très intéressants pour les applications automobiles. Les caractéristiques mécaniques de ces matériaux sont en bon accord avec le… (more)

▼

Les Thermoplastique Polyoléfine (TPO) se sont avérés très intéressants pour les applications automobiles. Les caractéristiques mécaniques de ces matériaux sont en bon accord avec le contexte environnemental et économique de la dernière décennie. En fait, au-delà de leur coût et recyclabilité, ils permettent un gain de poids important, une excellente flexibilité de conception et de hautes qualité en terme d'apparence ou de caractéristiques tactiles et olfactives. Le but de cette étude était de modéliser le comportement des nouvelles feuilles de TPO pour les applications de thermoformage. Le matériau étudié peut atteindre de très hautes valeurs d'allongement (jusqu’à 800%) et se distingue par une isotropie transverse. Afin de prédire correctement la distribution de l'épaisseur des pièces thermoformées finales, des essais detraction uniaxiale ont été menés le long des directions longitudinale, transversale et diagonale et à 5 températures différentes de ambiante à 120 °C. Un nouveau modèle hyperélastique isotrope transverstal a été développé. Les paramètres matériau à chacune des températures ont été identifiés en utilisant des méthodes inverses, et de bons résultats ont été obtenus. La procédure d'identification s'est avéré être difficile en raison de la grande sensibilité des paramètres et les problèmes d'instabilité en grandes déformations. Des techniques de mesures champ de déplacement 3D ont finalement été menées et associés à un test de thermoformage afin de valider la procédure matériel d'identification.

Thermoplastic PolyOiefin (TPO) materials have shown great interest for automotive applications. The mechanical characteristics of these materials are in good agreements with the environmental and economical context of the last decade. ln fact, beyond their cost and recyclability, they allow important weight gain, excellent design flexibility, and high quality whether in term of appearance or tactile and olfactory perceptions. The aim of this study was to model the behavior of new TPO sheets for thermoforming applications. The studied material can reach very high stretch ranges (up to 800%) and was found to be transversely isotropie. ln order to properly predict the thickness distribution of the final thermoformed parts, uniaxial tensile tests were performed along the longitudinal, transverse and diagonal directions, at 5 different temperatures from ambient to 120°C. A new transversely isotropic hyperelastic model was developed using User Subroutines in Abaqus software. The material parameters at each temperature have been identified using inverse methods, and good results have been obtained. The identification procedure has shown to be difficult because of the high sensitivity of the material parameters and the instability problems at high stretch ranges. 3D displacement field techniques were finally conducted and associated to a thermoforming test in order to validate the material parameter identification procedure.

Advisors/Committee Members: Rachik, Mohamed (thesis director).

Subjects/Keywords: Hyperélasticité; Identification inverse; Mesures de champs; Modélisation; TPO; Thermoplastics; Anisotropy; Polyolefins; Hyperelasticity; Optimization; Mathematical models

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Oueslati, Z. (2015). Modèle de comportement pour la modélisation du thermoformage de feuilles plastiques multicouches : Constitutive law for modeling multilayered thermplastic sheets thermoforming. (Doctoral Dissertation). Compiègne. Retrieved from http://www.theses.fr/2015COMP2213

Chicago Manual of Style (16^th Edition):

Oueslati, Zied. “Modèle de comportement pour la modélisation du thermoformage de feuilles plastiques multicouches : Constitutive law for modeling multilayered thermplastic sheets thermoforming.” 2015. Doctoral Dissertation, Compiègne. Accessed March 04, 2021. http://www.theses.fr/2015COMP2213.

MLA Handbook (7^th Edition):

Oueslati, Zied. “Modèle de comportement pour la modélisation du thermoformage de feuilles plastiques multicouches : Constitutive law for modeling multilayered thermplastic sheets thermoforming.” 2015. Web. 04 Mar 2021.

Vancouver:

Oueslati Z. Modèle de comportement pour la modélisation du thermoformage de feuilles plastiques multicouches : Constitutive law for modeling multilayered thermplastic sheets thermoforming. [Internet] [Doctoral dissertation]. Compiègne; 2015. [cited 2021 Mar 04]. Available from: http://www.theses.fr/2015COMP2213.

Council of Science Editors:

Oueslati Z. Modèle de comportement pour la modélisation du thermoformage de feuilles plastiques multicouches : Constitutive law for modeling multilayered thermplastic sheets thermoforming. [Doctoral Dissertation]. Compiègne; 2015. Available from: http://www.theses.fr/2015COMP2213

Université de Grenoble

18. Machado, Guilherme. Contribution à l'étude de l'anisotropie induite par l'effet Mullins dans les élastomères silicones chargés : A contribution to the study of induced anisotropy by Mullins effect in silicone rubber.

Degree: Docteur es, Matériaux, mécanique, génie civil, électrochimie, 2011, Université de Grenoble

URL: http://www.theses.fr/2011GRENI029

►

Le présent travail étudie la caractérisation expérimentale et la modélisation de l'anisotropie induite par effet Mullins, i.e., la perte de raideur après les premiers cycles… (more)

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Le présent travail étudie la caractérisation expérimentale et la modélisation de l'anisotropie induite par effet Mullins, i.e., la perte de raideur après les premiers cycles de chargement, très souvent observée dans les matériaux de type élastomère. Après une description des caractéristiques mécaniques du matériau silicone utilisé dans notre étude, des essais expérimentaux originaux sont développés pour créer des historiques de chargement complexes. D'une part, des successions d'essais de traction uniaxiale classiques sont réalisées, avec changement de directions de chargement. D'autre part, des états hétérogènes de contrainte et déformation obtenus lors d'essais de gonflement de membrane circulaire ont été complètement caractérisés grâce à des mesures de champs cinématiques réalisées par la méthode de corrélations d'images 3D ; les chargements effectués sont alors de type traction biaxiale-traction simple. Les paramètres clés pour la modélisation de l'effet Mullins ont ainsi pu être mis en évidence, avec notamment ses parts isotrope et anisotrope. Un modèle a ainsi été développé à partir d'une théorie de double réseau prenant en compte des critères expérimentalement motivés. Une version adaptée à une implantation simple dans un code de calculs éléments finis est finalement développée pour la réalisation de calculs de structures.

The present work studies the experimental characterization and modeling of the anisotropy induced by Mullins effect, i.e., the loss of stiffness in the first loading cycles, often observed in rubber-like materials. After a description of the mechanical characteristics of the particular silicone material used in our study, experimental tests are developed to create original and complex loading histories. First, successions of conventional uniaxial tensile tests are performed with changing directions of loading. Second, the state of heterogeneous stress and strain obtained in circular membrane swelling tests was completely characterized by means of kinematic field measurements made by the 3D image correlation method, and the loadings are then biaxial tension followed by uniaxial traction. The key parameters for modeling the Mullins effect were able to be identified, including its isotropic and anisotropic parts. A model was thus developed based on the double-network theory taking into account the experimentally motivated criteria. A suitable version with simple implementation in a finite element computer code was finally developed to allow the calculation of a structural part.

Advisors/Committee Members: Favier, Denis (thesis director).

Subjects/Keywords: Effet Mullins; Hyperélasticité; Élastomères silicone; Anisotropie; Mullins effect; Hyperelasticity; Silicone rubber; Anistropy

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Machado, G. (2011). Contribution à l'étude de l'anisotropie induite par l'effet Mullins dans les élastomères silicones chargés : A contribution to the study of induced anisotropy by Mullins effect in silicone rubber. (Doctoral Dissertation). Université de Grenoble. Retrieved from http://www.theses.fr/2011GRENI029

Chicago Manual of Style (16^th Edition):

Machado, Guilherme. “Contribution à l'étude de l'anisotropie induite par l'effet Mullins dans les élastomères silicones chargés : A contribution to the study of induced anisotropy by Mullins effect in silicone rubber.” 2011. Doctoral Dissertation, Université de Grenoble. Accessed March 04, 2021. http://www.theses.fr/2011GRENI029.

MLA Handbook (7^th Edition):

Machado, Guilherme. “Contribution à l'étude de l'anisotropie induite par l'effet Mullins dans les élastomères silicones chargés : A contribution to the study of induced anisotropy by Mullins effect in silicone rubber.” 2011. Web. 04 Mar 2021.

Vancouver:

Machado G. Contribution à l'étude de l'anisotropie induite par l'effet Mullins dans les élastomères silicones chargés : A contribution to the study of induced anisotropy by Mullins effect in silicone rubber. [Internet] [Doctoral dissertation]. Université de Grenoble; 2011. [cited 2021 Mar 04]. Available from: http://www.theses.fr/2011GRENI029.

Council of Science Editors:

Machado G. Contribution à l'étude de l'anisotropie induite par l'effet Mullins dans les élastomères silicones chargés : A contribution to the study of induced anisotropy by Mullins effect in silicone rubber. [Doctoral Dissertation]. Université de Grenoble; 2011. Available from: http://www.theses.fr/2011GRENI029

19. Crabbé, Blandine. Gradient damage models in large deformation : Modèles d'endommagement à gradient en grandes déformations.

Degree: Docteur es, Mécanique des matériaux, 2018, Université Paris-Saclay (ComUE)

URL: http://www.theses.fr/2018SACLX085

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Les modèles d'endommagement à gradient, aussi dénommés modèles à champs de phases, sont désormais largement utilisés pour modéliser la rupture fragile et ductile, depuis l'initiation… (more)

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Les modèles d'endommagement à gradient, aussi dénommés modèles à champs de phases, sont désormais largement utilisés pour modéliser la rupture fragile et ductile, depuis l'initiation de l'endommagement jusqu'à la propagation d'une fissure. Cependant, la majorité des études disponibles dans la littérature ne concerne que le cadre des petites déformations, et très peu d'études poussées ont été menées afin d'étudier leur pertinence dans un contexte de grandes déformations. Ce serait pourtant d'un intérêt primordial, notamment pour l'industrie pneumatique, qui deviendrait alors capable de prédire plus précisément l'initiation de l'endommagement dans ses structures.Dans la première partie de ce travail, nous établissons des solutions analytiques d'évolution de l'endommagement (homogène et localisée) pour des matériaux visqueux, en petites et en grandes déformations. En petites déformations, les modèles rhéologiques de Maxwell et Poynting-Thomson sont étudiés, et en grandes déformations, les modèles de Maxwell et Zener sont choisis. Une étude sur l'évolution de l'endommagement dans un cas purement hyperélastique est aussi menée.A cette première partie analytique succède une partie numérique, qui détaille l'implémentation des modèles d'endommagement à gradient dans des codes éléments finis en grandes déformations. De même qu'en petites déformations, une stratégie de minimisation alternée est adoptée pour résoudre successivement les problèmes d'endommagement et de déplacement. Le matériau suit une loi de Mooney-Rivlin quasi-incompressible, et une méthode mixte en déplacement-pression est utilisée. Des tests en 2D et 3D sont effectués, qui mettent en évidence la capacité des modèles à initier de l'endommagement en grandes déformations.Les modèles d'endommagement utilisés pour la seconde partie ne sont cependant capables d'initier de l'endommagement que dans les zones où la déformation est importante, c'est-à-dire dans les zones de forte contrainte déviatorique. Il a toutefois été montré que certains matériaux polymères, quasi-incompressibles, s'endommagent dans les zones de forte pression hydrostatique. Par conséquent, la recherche et l'étude d'un modèle d'endommagement capable d'initier de l'endommagement dans les zones de forte pression, pour des matériaux quasi-incompressibles lorsqu'ils sont sains, fait l'objet d'une troisième partie.Enfin, la croissance brusque de cavités dans un matériau hyperélastique, appelée phénomène de cavitation, est étudiée, ainsi que son interaction avec l'endommagement. Dans un premier temps, nous considérons la cavitation comme une simple bifurcation hyperélastique d'un matériau néo-hookéen compressible isotrope, et déterminons l'expression analytique de l'élongation critique pour laquelle la cavitation fait son apparition. Dans un second temps, nous montrons qu'il y a une compétition entre la cavitation et l'endommagement, et qu'en fonction de la valeur du ratio des élongations critiques respectives pour chaque phénomène, deux types de rupture apparaissent.

Gradient damage models, also…

Advisors/Committee Members: Marigo, Jean-Jacques (thesis director).

Subjects/Keywords: Endommagement; Rupture; Cavitation; Hyperélasticité; Pression; Viscoélasticité; Damage; Rupture; Cavitation; Hyperelasticity; Pressure; Viscoelasticity; 531.015

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Crabbé, B. (2018). Gradient damage models in large deformation : Modèles d'endommagement à gradient en grandes déformations. (Doctoral Dissertation). Université Paris-Saclay (ComUE). Retrieved from http://www.theses.fr/2018SACLX085

Chicago Manual of Style (16^th Edition):

Crabbé, Blandine. “Gradient damage models in large deformation : Modèles d'endommagement à gradient en grandes déformations.” 2018. Doctoral Dissertation, Université Paris-Saclay (ComUE). Accessed March 04, 2021. http://www.theses.fr/2018SACLX085.

MLA Handbook (7^th Edition):

Crabbé, Blandine. “Gradient damage models in large deformation : Modèles d'endommagement à gradient en grandes déformations.” 2018. Web. 04 Mar 2021.

Vancouver:

Crabbé B. Gradient damage models in large deformation : Modèles d'endommagement à gradient en grandes déformations. [Internet] [Doctoral dissertation]. Université Paris-Saclay (ComUE); 2018. [cited 2021 Mar 04]. Available from: http://www.theses.fr/2018SACLX085.

Council of Science Editors:

Crabbé B. Gradient damage models in large deformation : Modèles d'endommagement à gradient en grandes déformations. [Doctoral Dissertation]. Université Paris-Saclay (ComUE); 2018. Available from: http://www.theses.fr/2018SACLX085

Université Montpellier II

20. Jaudouin, Olivier. Physico-chimie de matériaux à base d'élastomères modifiés hyperélastiques : Physical chemistry of materials based on modified hyperelastic elastomers.

Degree: Docteur es, Chimie et physicochimie des matériaux, 2012, Université Montpellier II

URL: http://www.theses.fr/2012MON20036

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Cette thèse vise à développer des matériaux destinés à remplacer les gants des boîtes à gants utilisées en milieu nucléaire confiné par des disques élastomères… (more)

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Cette thèse vise à développer des matériaux destinés à remplacer les gants des boîtes à gants utilisées en milieu nucléaire confiné par des disques élastomères pouvant prendre la forme des mains lorsqu'un opérateur insère son bras et revenir à leur forme initiale lorsqu'il l'enlève. Le but du travail est de réaliser et d'étudier les propriétés physico-chimiques de matériaux capables de se déformer à plus de 2000 %, à être totalement élastique, à résister au déchirement et aux radiations. Dans un premier temps, une étude bibliographique a montré que les matériaux les plus susceptibles d'y répondre sont les élastomères thermoplastiques. Des matériaux de deux familles d'élastomères thermoplastiques ont donc été réalisés et étudiés. Les premiers sont les élastomères thermoplastiques polyuréthanes. L'influence de la stœchiométrie des monomères et de la structure chimique de différents allongeurs de chaînes sur les propriétés mécaniques a été étudiée. Il en ressort que ces matériaux sont trop visqueux pour répondre au cahier des charges mais une relation intéressante de linéarité entre la contrainte à l'écoulement et le taux de viscosité de l'ensemble de ces formulations a été observée. Les seconds matériaux sont des copolymères Styrène-Ethylène-Butylène-Styrène (SEBS). Les effets du procédé de mise en œuvre ainsi que l'incorporation de plastifiants, de nanoparticules ou de polyuréthane sur les propriétés mécaniques de ces matériaux ont été étudiés. Il a été mis en évidence que le procédé de mise en œuvre influence fortement les propriétés mécaniques et que l'ajout de nanoparticules et de polyuréthane permet d'améliorer certaines propriétés mécaniques. Globalement, les matériaux développés ont des propriétés très proches de celles de matériaux hyperélastiques.

The aim of this PhD work is to replace current gloves of gloveboxes used in nuclear area by elastomer discs which could take the shape of the arm of an operator and come back to their original shape when the arm is removed. The goal of the work is to design and study a material meeting the following specifications: at least 2 000 % strain at break, very high elastic properties, tear and radiation resistant. A bibliographic study showed that the most relevant materials are thermoplastic elastomers. As a consequence, two kinds of these materials were formulated. First ones are thermoplastic polyurethane elastomers. The influence of stoichiometric ratios and different chain extenders on mechanical properties was studied. These materials are too viscous to match the specifications but an interesting linear relation between flow stress and viscosity ratio was observed. Second ones are Styrene-Ethylene-Butylene-Styrene copolymers (SEBS). Studies on the influence of the process and incorporation of plasticizers, nanoparticules or polyurethane were carried out. It was highlighted that the process strongly influences mechanical properties and addition of nanoparticules or polyurethane can increase some of these properties. On the whole, the materials developed are very…

Advisors/Committee Members: Robin, Jean-Jacques (thesis director), Lopez-Cuesta, José-Marie (thesis director).

Subjects/Keywords: Elastomères thermoplastiques; Polyuréthane; Sebs; Propriétés mécaniques; Hyperélasticité; Thermoplastic elastomers; Polyurethane; Sebs; Mechanical properties; Hyperelasticity

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Jaudouin, O. (2012). Physico-chimie de matériaux à base d'élastomères modifiés hyperélastiques : Physical chemistry of materials based on modified hyperelastic elastomers. (Doctoral Dissertation). Université Montpellier II. Retrieved from http://www.theses.fr/2012MON20036

Chicago Manual of Style (16^th Edition):

Jaudouin, Olivier. “Physico-chimie de matériaux à base d'élastomères modifiés hyperélastiques : Physical chemistry of materials based on modified hyperelastic elastomers.” 2012. Doctoral Dissertation, Université Montpellier II. Accessed March 04, 2021. http://www.theses.fr/2012MON20036.

MLA Handbook (7^th Edition):

Jaudouin, Olivier. “Physico-chimie de matériaux à base d'élastomères modifiés hyperélastiques : Physical chemistry of materials based on modified hyperelastic elastomers.” 2012. Web. 04 Mar 2021.

Vancouver:

Jaudouin O. Physico-chimie de matériaux à base d'élastomères modifiés hyperélastiques : Physical chemistry of materials based on modified hyperelastic elastomers. [Internet] [Doctoral dissertation]. Université Montpellier II; 2012. [cited 2021 Mar 04]. Available from: http://www.theses.fr/2012MON20036.

Council of Science Editors:

Jaudouin O. Physico-chimie de matériaux à base d'élastomères modifiés hyperélastiques : Physical chemistry of materials based on modified hyperelastic elastomers. [Doctoral Dissertation]. Université Montpellier II; 2012. Available from: http://www.theses.fr/2012MON20036

Brno University of Technology

21. Holubář, Oldřich. Analýza šíření tlakové vlny v aortě: Analysis of pulse wave propagation in aorta.

Degree: 2019, Brno University of Technology

URL: http://hdl.handle.net/11012/17996

► This master thesis is focused on usage of monitoring pulse wave propagation in aortic system in a field of diagnostic abdominal aortic aneurysm (AAA). There… (more)

Subjects/Keywords: aneurysma; interakce tělesa s tekutinou; hyperelasticita; MKP; FSI; aneurysm; fluid structure interaction; hyperelasticity; FEM; FSI

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Holubář, O. (2019). Analýza šíření tlakové vlny v aortě: Analysis of pulse wave propagation in aorta. (Thesis). Brno University of Technology. Retrieved from http://hdl.handle.net/11012/17996

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Holubář, Oldřich. “Analýza šíření tlakové vlny v aortě: Analysis of pulse wave propagation in aorta.” 2019. Thesis, Brno University of Technology. Accessed March 04, 2021. http://hdl.handle.net/11012/17996.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Holubář, Oldřich. “Analýza šíření tlakové vlny v aortě: Analysis of pulse wave propagation in aorta.” 2019. Web. 04 Mar 2021.

Vancouver:

Holubář O. Analýza šíření tlakové vlny v aortě: Analysis of pulse wave propagation in aorta. [Internet] [Thesis]. Brno University of Technology; 2019. [cited 2021 Mar 04]. Available from: http://hdl.handle.net/11012/17996.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Holubář O. Analýza šíření tlakové vlny v aortě: Analysis of pulse wave propagation in aorta. [Thesis]. Brno University of Technology; 2019. Available from: http://hdl.handle.net/11012/17996

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

22. Basile, Graziano. Analisi teorico sperimentale di materiali iperelastici.

Degree: 2012, Università degli Studi di Catania

URL: http://hdl.handle.net/10761/1108

► Il presente lavoro è incentrato sulla caratterizzazione di materiali a comportamento Iperelastico, e quindi volto alla determinazione dei parametri della funzione energia di deformazione. Per… (more)

▼ Il presente lavoro è incentrato sulla caratterizzazione di materiali a comportamento Iperelastico, e quindi volto alla determinazione dei parametri della funzione energia di deformazione. Per la realizzazione delle prove meccaniche, sono stati progettati e realizzati i sistemi di test di tipo planare, utilizzati anche per prove monoassiali, e di un opportuno sistema per test biassiali. I sistemi permettono in maniera agevole la realizzazione dei test necessari e passare in maniera veloce da un set-up ad un altro. Per l impossibilità di poter applicare le tecniche di estensimetria di contatto, per via delle grandi deformazioni in gioco, è presentata una metodologia di rilievo mediante l utilizzo di una camera CCD ad alta risoluzione ed una procedura automatica di post elaborazione e sincronizzazione dei dati provenienti dalla prova mediante l utilizzo dei software Labview® e Matlab®. Il sistema misuristico messo a punto ha dato ottimi risultati e la perfetta sovrapposizione delle curve sforzo-deformazione ottenute con le curve provenienti dalla macchina di prova, nel caso di prove monoassiali e planari, mostrando la bontà della procedura e l applicabilità sui test biassiali dove non è possibile effettuare un confronto diretto con i dati provenienti dalla macchina monoassiale. Il materiale utilizzato al raggiungimento dello scopo è un silicone commerciale, prodotto dalla Angst + Pfister, con sigla VMQ. Infine, ottenute le curve caratteristiche, quindi caratterizzato il materiale secondo il miglior fit con i modelli disponibili in letteratura, è stata verificata la rispondenza del modello con l analisi numerica agli elementi finiti. È stato anche proposto un metodo iterativo basato sull analisi dell immagine e analisi numeriche agli elementi finiti per l identificazione della componente volumetrica. Concludendo, il presente lavoro non ha avuto come unico obiettivo quello di testare un materiale a comportamento non lineare, ma anche quello di realizzare in maniera semplice ed accessibile una metodologia di test soprattutto nel caso bi-assiale e nel contempo capire e darne il giusto peso al termine volumetrico nei modelli di energia di deformazione.

Subjects/Keywords: Area 09 - Ingegneria industriale e dell'informazione; Hyperelasticity, Elastomers, Characterization, Biaxial, Mooney, Optical Method

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Basile, G. (2012). Analisi teorico sperimentale di materiali iperelastici. (Thesis). Università degli Studi di Catania. Retrieved from http://hdl.handle.net/10761/1108

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Basile, Graziano. “Analisi teorico sperimentale di materiali iperelastici.” 2012. Thesis, Università degli Studi di Catania. Accessed March 04, 2021. http://hdl.handle.net/10761/1108.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Basile, Graziano. “Analisi teorico sperimentale di materiali iperelastici.” 2012. Web. 04 Mar 2021.

Vancouver:

Basile G. Analisi teorico sperimentale di materiali iperelastici. [Internet] [Thesis]. Università degli Studi di Catania; 2012. [cited 2021 Mar 04]. Available from: http://hdl.handle.net/10761/1108.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Basile G. Analisi teorico sperimentale di materiali iperelastici. [Thesis]. Università degli Studi di Catania; 2012. Available from: http://hdl.handle.net/10761/1108

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

23. Lacour, Thomas. Modélisation de la vaporisation acoustique de gouttelettes micro- ou nano-métriques encapsulées par des coques hyperélastiques ou des tensio-actifs : Modeling acoustic vaporization of micro- or nano-metric encapsulated droplet within a hyperelastic shell or surfactants.

Degree: Docteur es, Acoustique, 2018, Sorbonne université

URL: http://www.theses.fr/2018SORUS469

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Les particules nanométriques à cœur liquide présentent un fort intérêt pour l’imagerie médicale, l’embolothérapie ou la délivrance ciblée de médicaments. Elles permettent de réduire les… (more)

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Les particules nanométriques à cœur liquide présentent un fort intérêt pour l’imagerie médicale, l’embolothérapie ou la délivrance ciblée de médicaments. Elles permettent de réduire les effets secondaires et la résistance des tumeurs. Leurs fonctions thérapeutiques peuvent être activées mécaniquement à l’aide d’ultrasons focalisés entraînant un changement de phase du liquide interne : c’est le processus de vaporisation acoustique. Un modèle à quatre phases (vapeur+liquide+coque+milieu externe) est proposé pour décrire la dynamique de la vaporisation acoustique, couplant une généralisation de l’équation de Rayleigh-Plesset avec l’équation de la chaleur dans les phases denses. Une attention particulière est donnée à la modélisation des propriétés mécaniques de l’encapsulation et notamment à la prise en compte des grandes transformations engendrées par le changement de phase. Deux types d’encapsulation sont considérés : une coque viscoélastique (viscosité linéaire + hyperélasticité) et une membrane de tensioactifs (tension de surface dynamique). Différents régimes de vaporisation sont définis suivant que la dynamique de la bulle de vapeur présente ou non des rebonds. Ces régimes dépendent, pour un fluide donné (ici des nanogouttelettes de PerFluoroPentane dans de l’eau), de six paramètres clefs : deux paramètres acoustiques (amplitude et fréquence), deux paramètres géométriques (volume de vapeur et volume liquide) et deux paramètres mécaniques (constantes élastiques linéaire et non linéaire pour la coque hyperélastique ou tension de surface initiale et module élastique pour la tension de surface). Un seuil de vaporisation séparant ces différents régimes est alors proposé, dont la sensibilité aux paramètres précédemment cités est étudiée. L’existence d’un optimum d’excitation acoustique minimale en amplitude pour atteindre la vaporisation sans rebond est mise en évidence.

Nanodroplets have great, promising medical applications such as contrast imaging, embolotherapy or targeted drug delivery. Their functions can be mechanically activated by means of focused ultrasound inducing a phase change of the inner liquid known as acoustic droplet vaporization (ADV) process. In this context, a four-phases (vapor+liquid+surfactant layer+surrounding environment) model of ADV is proposed. Attention is especially devoted to the large but finite deformation expected after the complete vaporization of the inner liquid. Two kinds of encapsulation are considered: a viscoelastic shell (linear viscosity and hyperelasticity) and a surfactants membrane (dynamical surface tension). Various responses to ultrasound excitation are illustrated, depending on surfactant properties and acoustical excitation parameters. Different classes of ADV outcomes are exhibited within a phase diagram, and a relevant threshold ensuring complete vaporization is defined. The dependence of this threshold with acoustical, geometrical and mechanical parameters is also discussed. Finaly, an optimum point is highlighted in the context of medical applications.

Advisors/Committee Members: Coulouvrat, François (thesis director), Valier-Brasier, Tony (thesis director).

Subjects/Keywords: Nanoparticules; Vaporisation; Rayleigh-Plesset; Hyperélasticité; Tensioactifs; Seuil; Nanoparticles; Vaporization; Rayleigh-Plesset; Hyperelasticity; Surfactants; Threshold; 620.2

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Lacour, T. (2018). Modélisation de la vaporisation acoustique de gouttelettes micro- ou nano-métriques encapsulées par des coques hyperélastiques ou des tensio-actifs : Modeling acoustic vaporization of micro- or nano-metric encapsulated droplet within a hyperelastic shell or surfactants. (Doctoral Dissertation). Sorbonne université. Retrieved from http://www.theses.fr/2018SORUS469

Chicago Manual of Style (16^th Edition):

Lacour, Thomas. “Modélisation de la vaporisation acoustique de gouttelettes micro- ou nano-métriques encapsulées par des coques hyperélastiques ou des tensio-actifs : Modeling acoustic vaporization of micro- or nano-metric encapsulated droplet within a hyperelastic shell or surfactants.” 2018. Doctoral Dissertation, Sorbonne université. Accessed March 04, 2021. http://www.theses.fr/2018SORUS469.

MLA Handbook (7^th Edition):

Lacour, Thomas. “Modélisation de la vaporisation acoustique de gouttelettes micro- ou nano-métriques encapsulées par des coques hyperélastiques ou des tensio-actifs : Modeling acoustic vaporization of micro- or nano-metric encapsulated droplet within a hyperelastic shell or surfactants.” 2018. Web. 04 Mar 2021.

Vancouver:

Lacour T. Modélisation de la vaporisation acoustique de gouttelettes micro- ou nano-métriques encapsulées par des coques hyperélastiques ou des tensio-actifs : Modeling acoustic vaporization of micro- or nano-metric encapsulated droplet within a hyperelastic shell or surfactants. [Internet] [Doctoral dissertation]. Sorbonne université; 2018. [cited 2021 Mar 04]. Available from: http://www.theses.fr/2018SORUS469.

Council of Science Editors:

Lacour T. Modélisation de la vaporisation acoustique de gouttelettes micro- ou nano-métriques encapsulées par des coques hyperélastiques ou des tensio-actifs : Modeling acoustic vaporization of micro- or nano-metric encapsulated droplet within a hyperelastic shell or surfactants. [Doctoral Dissertation]. Sorbonne université; 2018. Available from: http://www.theses.fr/2018SORUS469

Pontifical Catholic University of Rio de Janeiro

24. EDGAR NOBUO MAMIYA. [en] APPLICATION OF A CONTINUATED METHOD OF FINITE ELASTICITY PROBLEMS OF INCOMPRESSIBLE MATERIALS.

Degree: 2018, Pontifical Catholic University of Rio de Janeiro

URL: http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=33289

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[pt] Apresenta-se aqui uma aplicação do método de continuação, baseado no algoritmo de Euler-Quase Newton, a problemas de equilíbrio de materiais hiperelásticos incompressíveis sujeitos a… (more)

Subjects/Keywords: [pt] GRANDES DEFORMACOES; [en] LARGE STRAIN; [pt] MATERIAIS INCOMPRESSIVEIS; [en] INCOMPRESSIBLE MATERIALS; [pt] HIPERELASTICIDADE; [en] HYPERELASTICITY

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

MAMIYA, E. N. (2018). [en] APPLICATION OF A CONTINUATED METHOD OF FINITE ELASTICITY PROBLEMS OF INCOMPRESSIBLE MATERIALS. (Thesis). Pontifical Catholic University of Rio de Janeiro. Retrieved from http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=33289

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

MAMIYA, EDGAR NOBUO. “[en] APPLICATION OF A CONTINUATED METHOD OF FINITE ELASTICITY PROBLEMS OF INCOMPRESSIBLE MATERIALS.” 2018. Thesis, Pontifical Catholic University of Rio de Janeiro. Accessed March 04, 2021. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=33289.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

MAMIYA, EDGAR NOBUO. “[en] APPLICATION OF A CONTINUATED METHOD OF FINITE ELASTICITY PROBLEMS OF INCOMPRESSIBLE MATERIALS.” 2018. Web. 04 Mar 2021.

Vancouver:

MAMIYA EN. [en] APPLICATION OF A CONTINUATED METHOD OF FINITE ELASTICITY PROBLEMS OF INCOMPRESSIBLE MATERIALS. [Internet] [Thesis]. Pontifical Catholic University of Rio de Janeiro; 2018. [cited 2021 Mar 04]. Available from: http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=33289.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

MAMIYA EN. [en] APPLICATION OF A CONTINUATED METHOD OF FINITE ELASTICITY PROBLEMS OF INCOMPRESSIBLE MATERIALS. [Thesis]. Pontifical Catholic University of Rio de Janeiro; 2018. Available from: http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=33289

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Michigan

25. Bischoff, Jeffrey Edward. Constitutive modeling and testing of biological soft tissue.

Degree: PhD, Mechanical engineering, 2001, University of Michigan

URL: http://hdl.handle.net/2027.42/124834

► Biological soft tissue is a complex engineering material whose mechanical response is intimately connected to its heterogeneous, multilayered, biphasic structure. Tissues such as skin and… (more)

▼ Biological soft tissue is a complex engineering material whose mechanical response is intimately connected to its heterogeneous, multilayered, biphasic structure. Tissues such as skin and heart are composed of load bearing fibrous networks of collagen and elastin; ground substance containing proteins, sugars, and water; cells such as fibroblasts; and other tissue specific components like vasculature and hair follicles. The presence and orientation of these components result in a constitutive response that is nonlinear, anisotropic, and viscoelastic. Constitutive models have been proposed to model the mechanical behavior of these tissues but most are phenomenological such that the material parameters do not reflect the histology of the tissue. A sound microstructurally based model has the capability to accurately capture the constitutive response of tissue, satisfy basic continuum mechanical requirements by virtue of its physical basis, and yield clinically useful metrics of the mechanical response that relate to the underlying tissue histology. A new microstructural model has been developed that has as its basis an orthotropic network of nonlinear elastic fibers within an incompressible medium. The resulting constitutive response predicted by this model is nonlinear, hyperelastic, and orthotropic. The parameters within the model reflect the orientation and alignment of the underlying load bearing collagen network and thus reflect the histology of the tissue. This model has been used to fit data from uniaxial tension and load controlled biaxial tension experiments. Additionally, the orthotropy and nonlinearity demonstrated in newly acquired data from uniaxial compression tests on canine myocardium have been successfully captured using this model. Most mechanical tests on soft tissue do not result in homogeneous deformations, due to either complex boundary and loading conditions or tissue heterogeneity within the sample. For application of the new model to these problems, the model has been incorporated into commercial finite element code. The resulting computational model has been used to demonstrate the effects of spatially varying fiber orientation on the response of tissue to various common experimental protocols. Advisors/Committee Members: Arruda, Ellen M. (advisor), Grosh, Karl (advisor).

Subjects/Keywords: Biological; Constitutive Modeling; Hyperelasticity; Orthotropy; Soft Tissue; Testing

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Bischoff, J. E. (2001). Constitutive modeling and testing of biological soft tissue. (Doctoral Dissertation). University of Michigan. Retrieved from http://hdl.handle.net/2027.42/124834

Chicago Manual of Style (16^th Edition):

Bischoff, Jeffrey Edward. “Constitutive modeling and testing of biological soft tissue.” 2001. Doctoral Dissertation, University of Michigan. Accessed March 04, 2021. http://hdl.handle.net/2027.42/124834.

MLA Handbook (7^th Edition):

Bischoff, Jeffrey Edward. “Constitutive modeling and testing of biological soft tissue.” 2001. Web. 04 Mar 2021.

Vancouver:

Bischoff JE. Constitutive modeling and testing of biological soft tissue. [Internet] [Doctoral dissertation]. University of Michigan; 2001. [cited 2021 Mar 04]. Available from: http://hdl.handle.net/2027.42/124834.

Council of Science Editors:

Bischoff JE. Constitutive modeling and testing of biological soft tissue. [Doctoral Dissertation]. University of Michigan; 2001. Available from: http://hdl.handle.net/2027.42/124834

University of Waterloo

26. Nafo, Wanis. Mechanical Characterization of Soft Materials Using Volume-Controlled Cavitation.

Degree: 2020, University of Waterloo

URL: http://hdl.handle.net/10012/15727

► The mechanical properties of soft materials are used in a wide range of fields and applications including biomedical engineering, sports, and automobile industry, in addition… (more)

▼ The mechanical properties of soft materials are used in a wide range of fields and applications including biomedical engineering, sports, and automobile industry, in addition to medical applications. Therefore, several methods have been used to measure these properties including tension, compression, and indentation. This study focuses on the application of multiaxial loading using cavitation mechanics to measure nonlinear mechanical properties of soft materials. It was found that applying controlled cavitation within the internal structure of soft materials provided enough information to characterize their mechanical behavior. This is done by inserting a needle-balloon tool inside the tested material while being attached to a system that allows for injections of an incompressible fluid (water) into the balloon. To establish this methodology as a robust characterization technique of the mechanics of soft materials, it was used in a four-stages investigation: developing an analytical framework to characterize the non-linear elastic behavior of rubber-like materials (elastomeric gels), measuring the hyperelastic properties of soft biological tissues (porcine liver), comparing the cavity expansion test with a conventional uniaxial tensile testing, and establishing an analytical framework to characterize the time-dependent behavior of viscoelastic materials. In the first stage, a solution that relates the applied radial loads and tangential deformation is introduced. This solution allows the calibration of hyperelastic strain energy functions (SEF), which were Yeoh, Arruda-Boyce and Ogden (used in all stages). Finite element simulations were used to validate the material parameters of the three hyperelastic models. Computed tomography (CT) imaging was used to validate the spherical configuration assumption of the inflated balloon inside the sample. The validation process considered the two types of stresses generated during the test, radial and hoop stresses. It was observed that the radial stresses were insignificant compared to the hoop stresses. In the second stage, a smaller balloon was used to test porcine liver tissues; however, the protocol of this stage was similar to the first stage. Few changes were introduced to the definition of the deformation term, as a result, the measured deformations in the cavity test coincided with the deformation levels reported in literature. In addition, the three hyperelastic models predicted initial shear moduli that agreed with their counterparts reported in literature using conventional testing techniques. To understand the similarities and differences between the cavity expansion test and conventional axial loading, the third stage addressed the comparison between the cavitation and uniaxial tension characterization. The comparison focused on the stress levels, range of strains as well as the initial shear moduli. It was found that the strain levels in the hydrogels were similar up to the failure point. In addition, the hoop stresses generated due to cavity loads were…

Subjects/Keywords: mechanical characterization; Cavity expansion; hyperelasticity; viscoelasticity; computed tomography; biological tissues; PVA hydrogels; Tissues; Mechanical properties; Cavitation; Elasticity; Tomography; Colloids

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Nafo, W. (2020). Mechanical Characterization of Soft Materials Using Volume-Controlled Cavitation. (Thesis). University of Waterloo. Retrieved from http://hdl.handle.net/10012/15727

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Nafo, Wanis. “Mechanical Characterization of Soft Materials Using Volume-Controlled Cavitation.” 2020. Thesis, University of Waterloo. Accessed March 04, 2021. http://hdl.handle.net/10012/15727.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Nafo, Wanis. “Mechanical Characterization of Soft Materials Using Volume-Controlled Cavitation.” 2020. Web. 04 Mar 2021.

Vancouver:

Nafo W. Mechanical Characterization of Soft Materials Using Volume-Controlled Cavitation. [Internet] [Thesis]. University of Waterloo; 2020. [cited 2021 Mar 04]. Available from: http://hdl.handle.net/10012/15727.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Nafo W. Mechanical Characterization of Soft Materials Using Volume-Controlled Cavitation. [Thesis]. University of Waterloo; 2020. Available from: http://hdl.handle.net/10012/15727

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Jönköping University

27. Montagut, Arturo Sancho. Material Characterization for the Simulation of Drop Tests Against PMMA Sheets.

Degree: Materials and Manufacturing, 2020, Jönköping University

URL: http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-49494

► There is a high demand for implementing simulations in the design and product devel-opment processes, avoiding the execution of costly tests on prototypes and… (more)

Subjects/Keywords: Abaqus; Polymers; PMMA; Acrylic; Simulation; Material Models; Hyperelasticity; Plasticity; Viscoelasticity; Drucker Prager; Yeoh; Drop Test; Luminaires; Other Materials Engineering; Annan materialteknik

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Montagut, A. S. (2020). Material Characterization for the Simulation of Drop Tests Against PMMA Sheets. (Thesis). Jönköping University. Retrieved from http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-49494

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Montagut, Arturo Sancho. “Material Characterization for the Simulation of Drop Tests Against PMMA Sheets.” 2020. Thesis, Jönköping University. Accessed March 04, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-49494.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Montagut, Arturo Sancho. “Material Characterization for the Simulation of Drop Tests Against PMMA Sheets.” 2020. Web. 04 Mar 2021.

Vancouver:

Montagut AS. Material Characterization for the Simulation of Drop Tests Against PMMA Sheets. [Internet] [Thesis]. Jönköping University; 2020. [cited 2021 Mar 04]. Available from: http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-49494.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Montagut AS. Material Characterization for the Simulation of Drop Tests Against PMMA Sheets. [Thesis]. Jönköping University; 2020. Available from: http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-49494

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Universidade do Rio Grande do Sul

28. Lancini, Emmanuel. Caracterização constitutiva de elastômeros utilizando testes de componentes.

Degree: 2012, Universidade do Rio Grande do Sul

URL: http://hdl.handle.net/10183/55462

►

Análises numéricas confiáveis do comportamento mecânico de materiais como borrachas, dependem muito de uma calibração precisa do modelo constitutivo hiperelástico utilizado. Estes modelos são calibrados… (more)

▼

Análises numéricas confiáveis do comportamento mecânico de materiais como borrachas, dependem muito de uma calibração precisa do modelo constitutivo hiperelástico utilizado. Estes modelos são calibrados ajustando as curvas teóricas aos dados experimentais, obtidos por meio de ensaios usuais. Em muitos casos as amostras de matéria prima desses elastômeros já não se encontram disponíveis ou é impossível fabricar os corpos de prova requeridos. O objetivo deste trabalho é verificar a possibilidade de encontrar constantes constitutivas testando o próprio componente, ao invés dos usuais ensaios de tração, compressão e cisalhamento. A abordagem proposta consiste em criar uma rotina de programação associada a uma função custo onde, a partir de uma estimativa inicial de constantes constitutivas, sejam realizados processos iterativos de otimização buscando aproximar as curvas de força × deslocamento teórica e experimental. Um componente automotivo será utilizado nos estudos e dois modelos constitutivos hiperelásticos serão testados. As equações de tensões nominais dos modelos hiperelásticos serão utilizadas para predizer o comportamento teórico dos ensaios usuais, de forma a verificar a qualidade das constantes obtidas. Conclui-se que é possível utilizar o ensaio da própria peça para caracterizar o material hiperelástico, com resultados comparáveis aos que seriam obtidos com os ensaios típicos para esta aplicação.

The reliable numerical analysis of the mechanical behavior of rubber-like materials depends strongly on accurately calibrated hyperelastic constitutive models. Such models are calibrated by fitting theoretical curves against experimental data obtained in well known tests. In many cases samples of the original elastomer are no longer available or it is impossible to manufacture the specimens required by the standard tests. The aim of this work is verify the possibility of finding the constitutive constants by testing the actual component instead of the usual tensile, compression and shear tests. The proposed approach consists in creating a programming routine with a cost function that, starting from an initial estimate of the constitutive constants, iterate through an optimization algorithm in order to fit the theoretical force × displacement curves to the experimental ones. An automotive component will be used during the studies and two hyperelastic constitutive models will be tested. The nominal stress equations for the hyperelastic models are used to predict the standard tests behavior, to assess the quality of the constants obtained. The results shown that is possible to characterize an hyperelastic material by testing the actual component, with results comparable to those which would be obtained with standard tests.

Advisors/Committee Members: Marczak, Rogerio Jose.

Subjects/Keywords: Hyperelasticity; Elastômeros; Optimization; Elementos finitos; Otimização matemática; Constitutive parameters; Ensaios de materiais; Elastomers; Finite element updating

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Lancini, E. (2012). Caracterização constitutiva de elastômeros utilizando testes de componentes. (Thesis). Universidade do Rio Grande do Sul. Retrieved from http://hdl.handle.net/10183/55462

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Lancini, Emmanuel. “Caracterização constitutiva de elastômeros utilizando testes de componentes.” 2012. Thesis, Universidade do Rio Grande do Sul. Accessed March 04, 2021. http://hdl.handle.net/10183/55462.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Lancini, Emmanuel. “Caracterização constitutiva de elastômeros utilizando testes de componentes.” 2012. Web. 04 Mar 2021.

Vancouver:

Lancini E. Caracterização constitutiva de elastômeros utilizando testes de componentes. [Internet] [Thesis]. Universidade do Rio Grande do Sul; 2012. [cited 2021 Mar 04]. Available from: http://hdl.handle.net/10183/55462.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Lancini E. Caracterização constitutiva de elastômeros utilizando testes de componentes. [Thesis]. Universidade do Rio Grande do Sul; 2012. Available from: http://hdl.handle.net/10183/55462

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Queensland University of Technology

29. Moody, Hayley Ruscoe. Benchmarking of the biomechanical characteristics of normal and degraded articular cartilage to facilitate mathematical modelling.

Degree: 2006, Queensland University of Technology

URL: https://eprints.qut.edu.au/16402/

► In order to validate the appropriate functional characteristics of cartilage, we need to systematically study and understand what constitutes normality and degradation in cartilage. This… (more)

▼ In order to validate the appropriate functional characteristics of cartilage, we need to systematically study and understand what constitutes normality and degradation in cartilage. This thesis provides an important step in this direction. To understand the mechanical repercussions of disruption to the matrix properties, cartilage is often artificially degraded using common enzymes. Although the process of artificial degradation does not provide an accurate representation of osteoarthritis, it can provide insight into the biomechanical properties of single matrix components by examining the behaviour of the tissue following its removal. Through histological analysis utilising the optical absorbance measurements of Safranin O stain, this work has demonstrated that for a given time and enzyme concentration, the action of Trypsin on proteoglycans is highly variable and is dependent on: * The initial distribution and concentration of proteoglycans at different depths * The intrinsic sample depth * The location in the joint space, and * The medium type. These findings provide initial data towards a mathematical model which researchers can use to optimise Trypsin treatment of articular cartilage, and therefore model degeneration in vitro with a better degree of certainty. The variability noted in the distribution and concentration of proteoglycans, and most likely the collagen network, creates a large variation in the compressive and tensile stiffness of all samples, and total failure strain energy. The average values for each of these tests indicate that a loss of proteoglycan through Trypsin treatment results in decreased compressive stiffness, increased tensile stiffness, and little change to the failure strains or total failure strain energy. Conversely, disruption to the collagen network shows increased compressive and tensile stiffness, as well as failure strain and total failure strain energy. Due to the large variation in the results for each treatment group, the average values for the treated samples fall within the range of results for normal cartilage. These values cannot therefore be used as dependable parameters to benchmark cartilage, since the parameters for artificially degraded cartilage are within the normal levels. The Yeoh and Polynomial hyperelastic laws were found to best represent the material characteristics of cartilage across the range of tested samples, regardless of differences in health and strength. The results presented here provide important insight into the biomechanical outcomes of artificial degradation and provide direction for future research in this area.

Subjects/Keywords: articular cartilage; enzyme degradation; compression; hyperelasticity; fracture mechanics

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Moody, H. R. (2006). Benchmarking of the biomechanical characteristics of normal and degraded articular cartilage to facilitate mathematical modelling. (Thesis). Queensland University of Technology. Retrieved from https://eprints.qut.edu.au/16402/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Moody, Hayley Ruscoe. “Benchmarking of the biomechanical characteristics of normal and degraded articular cartilage to facilitate mathematical modelling.” 2006. Thesis, Queensland University of Technology. Accessed March 04, 2021. https://eprints.qut.edu.au/16402/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Moody, Hayley Ruscoe. “Benchmarking of the biomechanical characteristics of normal and degraded articular cartilage to facilitate mathematical modelling.” 2006. Web. 04 Mar 2021.

Vancouver:

Moody HR. Benchmarking of the biomechanical characteristics of normal and degraded articular cartilage to facilitate mathematical modelling. [Internet] [Thesis]. Queensland University of Technology; 2006. [cited 2021 Mar 04]. Available from: https://eprints.qut.edu.au/16402/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Moody HR. Benchmarking of the biomechanical characteristics of normal and degraded articular cartilage to facilitate mathematical modelling. [Thesis]. Queensland University of Technology; 2006. Available from: https://eprints.qut.edu.au/16402/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

30. Paul, Jordi. Nonlinear hyperelasticity-based mesh optimisation.

Degree: 2016, Technische Universität Dortmund

URL: http://dx.doi.org/10.17877/DE290R-17940

► In this work, various aspects of PDE-based mesh optimisation are treated. Different existing methods are presented, with the focus on a class of nonlinear mesh… (more)

Subjects/Keywords: Mesh optimisation; Hyperelasticity; Nonlinear optimisation; Nonlinear solvers; Preconditioning; r-adaptivity; 510; Nichtlineare Finite-Elemente-Methode; Adaptives Gitter; Hyperelastizität

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Paul, J. (2016). Nonlinear hyperelasticity-based mesh optimisation. (Doctoral Dissertation). Technische Universität Dortmund. Retrieved from http://dx.doi.org/10.17877/DE290R-17940

Chicago Manual of Style (16^th Edition):

Paul, Jordi. “Nonlinear hyperelasticity-based mesh optimisation.” 2016. Doctoral Dissertation, Technische Universität Dortmund. Accessed March 04, 2021. http://dx.doi.org/10.17877/DE290R-17940.

MLA Handbook (7^th Edition):

Paul, Jordi. “Nonlinear hyperelasticity-based mesh optimisation.” 2016. Web. 04 Mar 2021.

Vancouver:

Paul J. Nonlinear hyperelasticity-based mesh optimisation. [Internet] [Doctoral dissertation]. Technische Universität Dortmund; 2016. [cited 2021 Mar 04]. Available from: http://dx.doi.org/10.17877/DE290R-17940.

Council of Science Editors:

Paul J. Nonlinear hyperelasticity-based mesh optimisation. [Doctoral Dissertation]. Technische Universität Dortmund; 2016. Available from: http://dx.doi.org/10.17877/DE290R-17940

Open Access Theses and Dissertations