You searched for +publisher:"University of Colorado" +contributor:("Franck Vernerey").
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University of Colorado
1.
Boudaoui, Khalid.
Development of Educational Software for the Design of Slender Reinforced Concrete Columns.
Degree: MS, 2013, University of Colorado
URL: http://scholar.colorado.edu/cven_gradetds/22 
► Education of undergraduate students in first class of reinforced concrete design must include design of slender compression members since they are common components in…
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▼ Education of undergraduate students in first class of reinforced concrete design must include design of slender compression members since they are common components in structures such as buildings and bridges. Education must engage students to function as designers, that is, to determine the geometry of the member as well as the layout of the steel reinforcement to withstand a set of loadings. Educational software application, CU Slender Column, is developed to support the education of students in reinforced concrete design. CU Slender Column studies single slender reinforced concrete columns with circular cross section. Designs account for slenderness effects by applying the American Concrete Institute (ACI) 318 moment magnification method for both non-sway and sway frames. To help students in the design, CU Slender Column provides feedbacks relative to the accuracy of numerical values of strengths and loads as well as the satisfaction of ACI provisions. Also, it is demonstrated that CU Slender Column is an efficient tool able to deal with a wide range of design situations. The demonstration of the performance of CU Slender Column is done by developing 38 examples exploring different column designs passing or failing in strength or in ACI provisions.
Advisors/Committee Members: George Hearn, Abbie Liel, Franck Vernerey.
Subjects/Keywords: Columns; concrete design; loadings; University of Colorado; software; aci; Civil Engineering; Education; Educational Methods; Higher Education
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APA (6th Edition):
Boudaoui, K. (2013). Development of Educational Software for the Design of Slender Reinforced Concrete Columns. (Masters Thesis). University of Colorado. Retrieved from http://scholar.colorado.edu/cven_gradetds/22
Chicago Manual of Style (16th Edition):
Boudaoui, Khalid. “Development of Educational Software for the Design of Slender Reinforced Concrete Columns.” 2013. Masters Thesis, University of Colorado. Accessed November 22, 2019.
http://scholar.colorado.edu/cven_gradetds/22.
MLA Handbook (7th Edition):
Boudaoui, Khalid. “Development of Educational Software for the Design of Slender Reinforced Concrete Columns.” 2013. Web. 22 Nov 2019.
Vancouver:
Boudaoui K. Development of Educational Software for the Design of Slender Reinforced Concrete Columns. [Internet] [Masters thesis]. University of Colorado; 2013. [cited 2019 Nov 22].
Available from: http://scholar.colorado.edu/cven_gradetds/22.
Council of Science Editors:
Boudaoui K. Development of Educational Software for the Design of Slender Reinforced Concrete Columns. [Masters Thesis]. University of Colorado; 2013. Available from: http://scholar.colorado.edu/cven_gradetds/22
University of Colorado
2.
Garriga Font, Marti.
Micro-Crawlers in Confined Space: Volume Oscillating Hydrogels.
Degree: ME, 2016, University of Colorado
URL: http://scholar.colorado.edu/cven_gradetds/45
► Recent research has shown that certain polymer hydrogels with simple elongated geometries are capable of moving in a crawling fashion, their motion mechanics inspired…
(more)
▼ Recent research has shown that certain polymer hydrogels with simple elongated geometries are capable of moving in a crawling fashion, their motion mechanics inspired by small animals such as earthworms and amoeboids. The focus of this master's thesis is to study the motion capacity of soft matter robots based on polymer hydrogels that undergo periodic inflation and deflation, coupled with symmetry-breaking mechanisms in confined conditions representing a porous channel. A mathematical model in the continuum mechanics frame that evaluates the time-history evolution and motion capabilities of these gels has been developed.
The prime application of these robots is targeted drug delivery; their size, ranging from millimeters to micrometers, and mechanical features which allow for large elastic deformations, make them suitable candidates to carry drugs through porous media like the human body to specific locations, such as tumor cells or damaged tissue, and upon gel degradation release the drug. Targeted drug delivery has two significant advantages compared to current drug application: it allows for customization based on individual patient cellular activity and diminishes side effects. An example of the second advantage is traditional chemotherapy which kills cells that divide rapidly regardless of if they are cancer cells or other cell types that exhibit this behavior in normal circumstances such as bone marrow cells.
One of the main challenges of targeted drug delivery is ensuring that the robot moves successfully from the insertion point to the destination point through human body porous system, hence the motivation for this thesis.
Advisors/Committee Members: Franck Vernerey, Mark P. Stoykovich, Ronald Y. S. Pak.
Subjects/Keywords: robots; polymer hydrogels; targeted drug delivery; Mechanical Engineering
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APA (6th Edition):
Garriga Font, M. (2016). Micro-Crawlers in Confined Space: Volume Oscillating Hydrogels. (Thesis). University of Colorado. Retrieved from http://scholar.colorado.edu/cven_gradetds/45
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Garriga Font, Marti. “Micro-Crawlers in Confined Space: Volume Oscillating Hydrogels.” 2016. Thesis, University of Colorado. Accessed November 22, 2019.
http://scholar.colorado.edu/cven_gradetds/45.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Garriga Font, Marti. “Micro-Crawlers in Confined Space: Volume Oscillating Hydrogels.” 2016. Web. 22 Nov 2019.
Vancouver:
Garriga Font M. Micro-Crawlers in Confined Space: Volume Oscillating Hydrogels. [Internet] [Thesis]. University of Colorado; 2016. [cited 2019 Nov 22].
Available from: http://scholar.colorado.edu/cven_gradetds/45.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Garriga Font M. Micro-Crawlers in Confined Space: Volume Oscillating Hydrogels. [Thesis]. University of Colorado; 2016. Available from: http://scholar.colorado.edu/cven_gradetds/45
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Colorado
3.
Zhang, Boning.
Grain-Scale Computational Modeling of Quasi-Static and Dynamic Loading on Natural Soils.
Degree: PhD, 2016, University of Colorado
URL: http://scholar.colorado.edu/cven_gradetds/28
► The discrete properties and different constituents, i.e. sand grains, clay matrix, pore-air, and pore-water in natural soil make it very complicated to investigate its…
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▼ The discrete properties and different constituents, i.e. sand grains, clay matrix, pore-air, and pore-water in natural soil make it very complicated to investigate its mechanical behavior. As granular material, the macro-behavior of natural soil depends very much on the particle-level interactions. Thus it is necessary to develop a computational modeling for natural soils at grain-scale considering sand grains, clay matrix, pore-air, and pore-water.
The Discrete Element Method (DEM) is used very often to study the behaviors of sand grains. A three-dimensional DEM code ellip3d is extended to polyEllip3d to simulate sand grains using poly-ellipsoids, which are non-symmetric and have more resistance to rolling than ellipsoids. In order to bridge DEM simulation to experiments,
Colorado Mason sand grains in SMT images are approximated by poly-ellipsoids and these equivalent polyellipsoids can be used directly to conduct DEM simulations. In addition, a simple particle fracture model is proposed to study the fracture behavior of sand grains. This particle fracture model will be calibrated and compared with the experimental results.
A coupling model for DEM and Peri-Dynamics (PD) is established to study the sand-clay matrix interaction, in which cohesive soil clay matrix is modeled using PD with ability to fracture and fragment clay constituent. Both DEM-PD coupled model and Finite Element Analysis (FEA) are used to solve a rigid inclusion problem and their results are compared to semi-verify our DEM-PD model. In the case that the soil is purely cohesionless (e.g.,only sand grains) and modeled using DEM, then the pore-water is modeled using another particle method, Smoothed Particle Hydrodynamics (SPH). DEM-SPH coupled model is also developed to study the interaction between fluid and particles, which can be used in the future to conduct more simulations in sand-pore-water-system, such as drainage problem. Several test examples are conducted to verify the DEM-SPH coupling model in this research. The various C++ codes developed, such as polyEllip3d, DEM-SPH, and DEM-PD are parallelized using hybrid MPI/OpenMP.
Finally, stress and strain measures for granular material at large deformation are developed and implemented to study the macroscopic mechanical behavior of natural soils. Thus these stress and strain measures can be used in upscaling to bridge microscale (e.g., grain-scale in this research) to the macroscale (e.g., continuum scale of natural soil).
Advisors/Committee Members: Richard Regueiro, Ronald Pak, Jeong-Hoon Song, Franck Vernerey.
Subjects/Keywords: computational modeling; discrete element method; grain-scale; natural soils; peri-dynamics; smoothed particle hydrodynamics; Civil Engineering
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APA (6th Edition):
Zhang, B. (2016). Grain-Scale Computational Modeling of Quasi-Static and Dynamic Loading on Natural Soils. (Doctoral Dissertation). University of Colorado. Retrieved from http://scholar.colorado.edu/cven_gradetds/28
Chicago Manual of Style (16th Edition):
Zhang, Boning. “Grain-Scale Computational Modeling of Quasi-Static and Dynamic Loading on Natural Soils.” 2016. Doctoral Dissertation, University of Colorado. Accessed November 22, 2019.
http://scholar.colorado.edu/cven_gradetds/28.
MLA Handbook (7th Edition):
Zhang, Boning. “Grain-Scale Computational Modeling of Quasi-Static and Dynamic Loading on Natural Soils.” 2016. Web. 22 Nov 2019.
Vancouver:
Zhang B. Grain-Scale Computational Modeling of Quasi-Static and Dynamic Loading on Natural Soils. [Internet] [Doctoral dissertation]. University of Colorado; 2016. [cited 2019 Nov 22].
Available from: http://scholar.colorado.edu/cven_gradetds/28.
Council of Science Editors:
Zhang B. Grain-Scale Computational Modeling of Quasi-Static and Dynamic Loading on Natural Soils. [Doctoral Dissertation]. University of Colorado; 2016. Available from: http://scholar.colorado.edu/cven_gradetds/28
University of Colorado
4.
Margolis, Nate.
Hygromorphic Scales for Use in Water from Morning Dew and Elementary Model of Hydrogel Expansion Properties.
Degree: MS, Materials Science and Engineering, 2017, University of Colorado
URL: https://scholar.colorado.edu/mats_gradetds/5
► Secure access to water is a growing problem in the world today. Millions of people do not have contact with fresh or clean water…
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▼ Secure access to water is a growing problem in the world today. Millions of people do not have contact with fresh or clean water for drinking. Consuming dirty water leads to many illnesses and deaths every year. When water is scarce people are less likely to follow basic hygiene which also adds to the problem of sickness from water. Currently most of the population gets their water from run-off such as rivers, lakes and other fresh water bodies. Aquafers can also provide water, however, once they do not replenish themselves so once they are empty they will no longer provide a fresh water source. This is a serious problem because the population has grown to 7 billion people and only 2% of the world’s water is fresh water. Of this, most the fresh water is locked in the polar ice caps. This leaves only .77% of the available fresh water accessible for human use. While wealthy countries may not feel this burden due to their infrastructure. Impoverish countries will feel the full burden of a lack of water. This has led to a growing number of water conflicts over the years some of which have resulted in human deaths. There are several ways that people can collect water from the atmosphere such as collecting rain water or using a solar still to evaporate water out of an undrinkable source. In parts of the world where fog is prevalent, meshes have been used to collect the moisture from the air. However, these systems only work where the environment allows for it. In some places in the world, the only amount of water may come from morning dew. Certain places receive more water from morning dew than they do from annual precipitation. By studying nature, a novel water collection device was developed, tested and modeled. The model is compared to the test data to see the ways in which the device can be optimized. This could be used to help alleviate the growing problems of water shortages in specific parts of the world. The model and device design shows promising data but still has room for improvement. Potential changes for improved performance are explored.
Advisors/Committee Members: Franck Vernerey, Yunping Xi, Rong Long.
Subjects/Keywords: Biomimicry; Climate Change; Environment; Hydrogel; Hygromorphic Scales; Water Collection; Environmental Design; Materials Science and Engineering
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APA (6th Edition):
Margolis, N. (2017). Hygromorphic Scales for Use in Water from Morning Dew and Elementary Model of Hydrogel Expansion Properties. (Masters Thesis). University of Colorado. Retrieved from https://scholar.colorado.edu/mats_gradetds/5
Chicago Manual of Style (16th Edition):
Margolis, Nate. “Hygromorphic Scales for Use in Water from Morning Dew and Elementary Model of Hydrogel Expansion Properties.” 2017. Masters Thesis, University of Colorado. Accessed November 22, 2019.
https://scholar.colorado.edu/mats_gradetds/5.
MLA Handbook (7th Edition):
Margolis, Nate. “Hygromorphic Scales for Use in Water from Morning Dew and Elementary Model of Hydrogel Expansion Properties.” 2017. Web. 22 Nov 2019.
Vancouver:
Margolis N. Hygromorphic Scales for Use in Water from Morning Dew and Elementary Model of Hydrogel Expansion Properties. [Internet] [Masters thesis]. University of Colorado; 2017. [cited 2019 Nov 22].
Available from: https://scholar.colorado.edu/mats_gradetds/5.
Council of Science Editors:
Margolis N. Hygromorphic Scales for Use in Water from Morning Dew and Elementary Model of Hydrogel Expansion Properties. [Masters Thesis]. University of Colorado; 2017. Available from: https://scholar.colorado.edu/mats_gradetds/5
University of Colorado
5.
Hallowell, Spencer T.
Modeling the Micro Behavior and Failure of Collagen Based Fibrous Materials.
Degree: MS, 2011, University of Colorado
URL: https://scholar.colorado.edu/cven_gradetds/230
► The field of tissue engineering has expanded vastly over the last decade. Due to difficulties in testing tissues in vivo, numerical models must be produced…
(more)
▼ The field of tissue engineering has expanded vastly over the last decade. Due to difficulties in testing tissues in vivo, numerical models must be produced to determine their mechanical behavior. Load bearing tissues in mammals are typically composed of collagenous fibrous networks connected by covalent cross links. To accurately model the behavior of these complicated tissues, a two dimensional Representative Volume Element has been formulated. The RVE utilizes truss elements, linear elastic springs and constraint forces to provide accurate behavior. The RVE behavior is calibrated to mimic experimental tensile testing of collagen gels by Xu et al. (International Journal of Biomaterials, 2011, pp. 1-12). The RVE behavior represented that of the experiments including producing a "J" shaped stress-strain curve and a brittle failure point of rupture. The simple truss structure RVE is simple enough to be utilized in multiscale finite element methods, while still describing accurate behavior of collagenous materials.
Advisors/Committee Members: Franck Vernerey, Ronald Pak, Carlos Felippa, Jon Dow.
Subjects/Keywords: collagen; failure; finite element; mechanics; modeling; Civil Engineering; Structures and Materials
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APA (6th Edition):
Hallowell, S. T. (2011). Modeling the Micro Behavior and Failure of Collagen Based Fibrous Materials. (Masters Thesis). University of Colorado. Retrieved from https://scholar.colorado.edu/cven_gradetds/230
Chicago Manual of Style (16th Edition):
Hallowell, Spencer T. “Modeling the Micro Behavior and Failure of Collagen Based Fibrous Materials.” 2011. Masters Thesis, University of Colorado. Accessed November 22, 2019.
https://scholar.colorado.edu/cven_gradetds/230.
MLA Handbook (7th Edition):
Hallowell, Spencer T. “Modeling the Micro Behavior and Failure of Collagen Based Fibrous Materials.” 2011. Web. 22 Nov 2019.
Vancouver:
Hallowell ST. Modeling the Micro Behavior and Failure of Collagen Based Fibrous Materials. [Internet] [Masters thesis]. University of Colorado; 2011. [cited 2019 Nov 22].
Available from: https://scholar.colorado.edu/cven_gradetds/230.
Council of Science Editors:
Hallowell ST. Modeling the Micro Behavior and Failure of Collagen Based Fibrous Materials. [Masters Thesis]. University of Colorado; 2011. Available from: https://scholar.colorado.edu/cven_gradetds/230
University of Colorado
6.
Segura, Christopher L.
Implementation of Lumped Plasticity Models and Developments in an Object Oriented Nonlinear Finite Element Code.
Degree: MS, 2011, University of Colorado
URL: https://scholar.colorado.edu/cven_gradetds/237
► Numerical simulation tools capable of modeling nonlinear material and geometric behavior are important to structural engineers concerned with approximating the strength and deformation capacity…
(more)
▼ Numerical simulation tools capable of modeling nonlinear material and geometric behavior are important to structural engineers concerned with approximating the strength and deformation capacity of a structure. While structures are typically designed to behave linear elastic when subjected to building code design loads, exceedance of the linear elastic range is often an important consideration, especially with regards to structural response during hazard level events (i.e. earthquakes, hurricanes, floods), where collapse prevention is the primary goal. This thesis addresses developments made to Mercury, a nonlinear finite element program developed in MATLAB for numerical simulation and in C++ for real time hybrid simulation. Developments include the addition of three new constitutive models to extend Mercury's lumped plasticity modeling capabilities, a constitutive driver tool for testing and implementing Mercury constitutive models, and Mercury pre and post-processing tools. Mercury has been developed as a tool for transient analysis of distributed plasticity models, offering accurate nonlinear results on the material level, element level, and structural level. When only structural level response is desired (collapse prevention), obtaining material level results leads to unnecessarily lengthy computational time. To address this issue in Mercury, lumped plasticity capabilities are developed by implementing two lumped plasticity flexural response constitutive models and a column shear failure constitutive model. The models are chosen for implementation to address two critical issues evident in structural testing: column shear failure and strength and stiffness degradation under reverse cyclic loading. These tools make it possible to model post-peak behavior, capture strength and stiffness degradation, and predict global collapse. During the implementation process, a need was identified to create a simple program, separate from Mercury, to simplify the process of implementing a new constitutive model. A constitutive driver tool with a graphical user interface is developed to address this issue, providing benefits for Mercury development and classroom learning. A Mercury pre and post-processor graphical user interface is also implemented. The developed tool is a standalone application which allows Mercury users to visualize numerical models for verification and view analysis results without the need to transfer information. Mercury analysis may also be run from within the application. All necessary pre-process, analysis, and post-process procedures are, therefore, combined into the program, collectively referred to as Mercury++.
Advisors/Committee Members: Victor E. Saouma, Abbie Liel, Franck Vernerey.
Subjects/Keywords: finite element; graphical user interface; lumped plasticity; mercury; nonlinear structural analysis; object oriented MATLAB; Civil Engineering
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APA (6th Edition):
Segura, C. L. (2011). Implementation of Lumped Plasticity Models and Developments in an Object Oriented Nonlinear Finite Element Code. (Masters Thesis). University of Colorado. Retrieved from https://scholar.colorado.edu/cven_gradetds/237
Chicago Manual of Style (16th Edition):
Segura, Christopher L. “Implementation of Lumped Plasticity Models and Developments in an Object Oriented Nonlinear Finite Element Code.” 2011. Masters Thesis, University of Colorado. Accessed November 22, 2019.
https://scholar.colorado.edu/cven_gradetds/237.
MLA Handbook (7th Edition):
Segura, Christopher L. “Implementation of Lumped Plasticity Models and Developments in an Object Oriented Nonlinear Finite Element Code.” 2011. Web. 22 Nov 2019.
Vancouver:
Segura CL. Implementation of Lumped Plasticity Models and Developments in an Object Oriented Nonlinear Finite Element Code. [Internet] [Masters thesis]. University of Colorado; 2011. [cited 2019 Nov 22].
Available from: https://scholar.colorado.edu/cven_gradetds/237.
Council of Science Editors:
Segura CL. Implementation of Lumped Plasticity Models and Developments in an Object Oriented Nonlinear Finite Element Code. [Masters Thesis]. University of Colorado; 2011. Available from: https://scholar.colorado.edu/cven_gradetds/237
University of Colorado
7.
Figueroa, Jonathan Jorge.
A Comprehensive Analysis and Elementary Model of Phototropism and Gravitropism.
Degree: MS, 2012, University of Colorado
URL: https://scholar.colorado.edu/cven_gradetds/204
► The utilization of the surrounding environment is a distinct feature that plants harness to sustain equilibrium and continual maintenance. Plants undergo rapid changes and…
(more)
▼ The utilization of the surrounding environment is a distinct feature that plants harness to sustain equilibrium and continual maintenance. Plants undergo rapid changes and various stresses that add to an already complex system consisting of elaborate functions. Phototropism involves the activation of photoreceptive pigments, cell proteins and plant hormones through light reception which brings about curvature. Gravitropism is induced through the sedimentation of starch sacs that activate cells and allows for curvature response to gravity. Both processes are vital to the plant and can result in various structural responses. Recent research points to a specific plant hormone specified as auxin as the catalyst for differential growth and curvature.
An extensive analysis reveals the exact mechanisms behind phototropism and gravitropism from the molecular level to the global level. A plant experiencing a phototropic response utilizes specific pigments that differentiate the spectra of light. These protein based pigments localize to the plasma membrane of the plant cells and induces a state of phosphorylation. More proteins are activated and begin to interact with the naturally occurring auxin. Auxin then moves laterally across the different cell layers of the plant and produces curvature. Gravitropism follows a similar pattern but it is the endodermis of the plant that recognizes gravity. There are distinct organelles within the vacuoles of the cell that sediment in response to the vector of gravity. Upon sedimentation, an interaction with the cell's cytoskeleton takes place and proteins are again activated. Interaction with auxin occurs resulting in lateral movement that initiates curvature.
Cell expansion is the result of the interaction between auxin and the cell. Internal turgor pressure and cell wall compliance are the two main factors involved in cell expansion. A model is created with the relationship of auxin and cell expansion in terms of the different tropisms. In the model, the stem of a plant is considered and assumptions of curvature are made. Experimental data is gathered and comparisons with the model are drawn. The model is a substantial starting point but has room for improvement. The proper curvature response is simulated and potential applications are explored.
Advisors/Committee Members: Franck Vernerey, Ronald Y. S. Pak, Mark Stoykovich.
Subjects/Keywords: auxin; cell expansion; gravitropism; modelling; phototropism; Civil and Environmental Engineering
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APA (6th Edition):
Figueroa, J. J. (2012). A Comprehensive Analysis and Elementary Model of Phototropism and Gravitropism. (Masters Thesis). University of Colorado. Retrieved from https://scholar.colorado.edu/cven_gradetds/204
Chicago Manual of Style (16th Edition):
Figueroa, Jonathan Jorge. “A Comprehensive Analysis and Elementary Model of Phototropism and Gravitropism.” 2012. Masters Thesis, University of Colorado. Accessed November 22, 2019.
https://scholar.colorado.edu/cven_gradetds/204.
MLA Handbook (7th Edition):
Figueroa, Jonathan Jorge. “A Comprehensive Analysis and Elementary Model of Phototropism and Gravitropism.” 2012. Web. 22 Nov 2019.
Vancouver:
Figueroa JJ. A Comprehensive Analysis and Elementary Model of Phototropism and Gravitropism. [Internet] [Masters thesis]. University of Colorado; 2012. [cited 2019 Nov 22].
Available from: https://scholar.colorado.edu/cven_gradetds/204.
Council of Science Editors:
Figueroa JJ. A Comprehensive Analysis and Elementary Model of Phototropism and Gravitropism. [Masters Thesis]. University of Colorado; 2012. Available from: https://scholar.colorado.edu/cven_gradetds/204
University of Colorado
8.
Kaufman, Yevgeniy.
The Influence of Representative Volume Element Size, Soil Fabric, and Interparticle Elasto-Plasticity in Three-Dimensional Ellipsoidal Discrete Element Modeling of Granular Assemblies.
Degree: ME, 2012, University of Colorado
URL: https://scholar.colorado.edu/cven_gradetds/283
► In this comparative study of RVEs, a DEM code ELLIP3D is utilized to simulate quartz sand in triaxial compression tests with particle assemblies attained…
(more)
▼ In this comparative study of RVEs, a DEM code ELLIP3D is utilized to simulate quartz sand in triaxial compression tests with particle assemblies attained from an in situ fabric generated by synchrotron X-ray microcomputed tomography. In order to attain meaningful results for engineered systems at the macroscopic scale using DEM, RVE volume sizes play a significant role in the accuracy of simulating physical experiments. Simulation time or the number of particles limits the capacity of DEM to simulate large-scale granular systems, which is why it is crucial to determine an efficient quantity and quality of RVEs. ELLIP3D simulations have been carried out to evaluate a minimum threshold for RVE size for which a comparison of results from various sized boxed particle assemblies provides valuable information on the quantitative behavior of RVEs. The mid-progress and final results of the ELLIP3D simulations are compared to experimental data from synchrotron micro-computed tomography (SMT) scans. These data containing the initial numerical packing from the scans provide us with the particles' radii, positions, and orientations which are approximated as ellipsoids, which is a current limitation of ELLIP3D, but extension to poly-ellipsoids is being planned. Additionally, a comparison between simulations of triaxial compression on in situ fabric versus a slightly displaced fabric due to gravity deposition on an assembly of ellipsoidal particles is explored. Furthermore, a bilinear elasto-plasticity constitutive model is implemented into ELLIP3D to explore a more realistic phenomenon within the interparticle interaction for materials that exhibit such behavior. Elasto-plastic deformation is appropriate in studies involving metallic powders. The results of a two-particle compaction simulation using DE modeling are compared to finite element (FE) simulations.
Advisors/Committee Members: Richard A. Regueiro, Franck Vernerey, Ronald Pak.
Subjects/Keywords: bilinear elasto-plasticity; discrete element modeling; distinct element modeling; granular materials; representative volume element; soil fabric; Engineering Mechanics; Geotechnical Engineering
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APA (6th Edition):
Kaufman, Y. (2012). The Influence of Representative Volume Element Size, Soil Fabric, and Interparticle Elasto-Plasticity in Three-Dimensional Ellipsoidal Discrete Element Modeling of Granular Assemblies. (Thesis). University of Colorado. Retrieved from https://scholar.colorado.edu/cven_gradetds/283
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Kaufman, Yevgeniy. “The Influence of Representative Volume Element Size, Soil Fabric, and Interparticle Elasto-Plasticity in Three-Dimensional Ellipsoidal Discrete Element Modeling of Granular Assemblies.” 2012. Thesis, University of Colorado. Accessed November 22, 2019.
https://scholar.colorado.edu/cven_gradetds/283.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Kaufman, Yevgeniy. “The Influence of Representative Volume Element Size, Soil Fabric, and Interparticle Elasto-Plasticity in Three-Dimensional Ellipsoidal Discrete Element Modeling of Granular Assemblies.” 2012. Web. 22 Nov 2019.
Vancouver:
Kaufman Y. The Influence of Representative Volume Element Size, Soil Fabric, and Interparticle Elasto-Plasticity in Three-Dimensional Ellipsoidal Discrete Element Modeling of Granular Assemblies. [Internet] [Thesis]. University of Colorado; 2012. [cited 2019 Nov 22].
Available from: https://scholar.colorado.edu/cven_gradetds/283.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Kaufman Y. The Influence of Representative Volume Element Size, Soil Fabric, and Interparticle Elasto-Plasticity in Three-Dimensional Ellipsoidal Discrete Element Modeling of Granular Assemblies. [Thesis]. University of Colorado; 2012. Available from: https://scholar.colorado.edu/cven_gradetds/283
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Colorado
9.
Wang, Xingang.
Thermal Strain of Concrete Under Low Temperatures and Durability and Processing Techniques of Concrete with Cnts.
Degree: MS, 2013, University of Colorado
URL: https://scholar.colorado.edu/cven_gradetds/291
► This thesis consists of two topics: Thermal strain of concrete under low temperatures, and durability and processing techniques of concrete with CNTs. The low…
(more)
▼ This thesis consists of two topics: Thermal strain of concrete under low temperatures, and durability and processing techniques of concrete with CNTs. The low temperature test studies the anti-freezing action of concrete under cooling environment. Concrete mixes using different amounts of air-entraining agent and water/cement ratios were made and cured under different humidity environments. During the cooling process from 10 ºC to -25 ºC, the strain of concrete was measured every 3~5 ºC. The strain-temperature curve of concrete under different mixing proportion was produced from these results. A numerical model was developed based on the theory of the self-consistent model. No knowledge of real pore shapes is needed to apply in the model. The only inputs for the model came from the (Brunauer-Emmett-Teller) BET test, which gave the pore size distribution of concrete sample. The validity of the numerical model was compared to the experimental results, and showed similarity in trend and peak strain. CNT is one of the most popular topics in engineering. CNT has an extremely high strength and Young's modulus. CNT is a nano-scale material, however, and tends to clump together, which makes it difficult to apply. Other research has successfully incorporated CNT into cement paste and polymer materials. This has not yet been done into concrete. This research mainly focuses on the important factors that must be solved to adopt CNT in concrete area. An ultrasonicator was used to aid the dispersion and distribution of CNT in water, while several chemicals were also adopted for this purpose. Both strength and durability were tested for CNT concrete of different mix designs. It is suggested that ultrasonicator can improve the strength of pure CNT concrete (without chemicals) by around 100%. In addition, the sodium polyacrylate treated CNT concrete has showed best durability result and good strength result.
Advisors/Committee Members: Yunping Xi, Franck Vernerey, Keith Porter.
Subjects/Keywords: cnt; concrete; low temperature; self consistent model; strength; Civil Engineering; Engineering Science and Materials
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APA (6th Edition):
Wang, X. (2013). Thermal Strain of Concrete Under Low Temperatures and Durability and Processing Techniques of Concrete with Cnts. (Masters Thesis). University of Colorado. Retrieved from https://scholar.colorado.edu/cven_gradetds/291
Chicago Manual of Style (16th Edition):
Wang, Xingang. “Thermal Strain of Concrete Under Low Temperatures and Durability and Processing Techniques of Concrete with Cnts.” 2013. Masters Thesis, University of Colorado. Accessed November 22, 2019.
https://scholar.colorado.edu/cven_gradetds/291.
MLA Handbook (7th Edition):
Wang, Xingang. “Thermal Strain of Concrete Under Low Temperatures and Durability and Processing Techniques of Concrete with Cnts.” 2013. Web. 22 Nov 2019.
Vancouver:
Wang X. Thermal Strain of Concrete Under Low Temperatures and Durability and Processing Techniques of Concrete with Cnts. [Internet] [Masters thesis]. University of Colorado; 2013. [cited 2019 Nov 22].
Available from: https://scholar.colorado.edu/cven_gradetds/291.
Council of Science Editors:
Wang X. Thermal Strain of Concrete Under Low Temperatures and Durability and Processing Techniques of Concrete with Cnts. [Masters Thesis]. University of Colorado; 2013. Available from: https://scholar.colorado.edu/cven_gradetds/291
University of Colorado
10.
Margolis, Nate.
Hygromorphic Scales for Use in Water from Morning Dew and Elementary Model of Hydrogel Expansion Properties.
Degree: MSMatSE, 2017, University of Colorado
URL: https://scholar.colorado.edu/mats_gradetds/7
► Secure access to water is a growing problem in the world today. Millions of people do not have contact with fresh or clean water…
(more)
▼ Secure access to water is a growing problem in the world today. Millions of people do not have contact with fresh or clean water for drinking. Consuming dirty water leads to many illnesses and deaths every year. When water is scarce people are less likely to follow basic hygiene which also adds to the problem of sickness from water. Currently most of the population gets their water from run-off such as rivers, lakes and other fresh water bodies. Aquafers can also provide water, however, once they do not replenish themselves so once they are empty they will no longer provide a fresh water source. This is a serious problem because the population has grown to 7 billion people and only 2% of the world’s water is fresh water. Of this, most the fresh water is locked in the polar ice caps. This leaves only .77% of the available fresh water accessible for human use. While wealthy countries may not feel this burden due to their infrastructure. Impoverish countries will feel the full burden of a lack of water. This has led to a growing number of water conflicts over the years some of which have resulted in human deaths. There are several ways that people can collect water from the atmosphere such as collecting rain water or using a solar still to evaporate water out of an undrinkable source. In parts of the world where fog is prevalent, meshes have been used to collect the moisture from the air. However, these systems only work where the environment allows for it. In some places in the world, the only amount of water may come from morning dew. Certain places receive more water from morning dew than they do from annual precipitation. By studying nature, a novel water collection device was developed, tested and modeled. The model is compared to the test data to see the ways in which the device can be optimized. This could be used to help alleviate the growing problems of water shortages in specific parts of the world. The model and device design shows promising data but still has room for improvement. Potential changes for improved performance are explored.
Advisors/Committee Members: Franck Vernerey, Yunping Xi, Rong Long.
Subjects/Keywords: biomimicry; climate change; environment; hydrogel; hygromorphic scales; water collection; Environmental Health; Materials Science and Engineering; Systems Engineering and Multidisciplinary Design Optimization
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APA (6th Edition):
Margolis, N. (2017). Hygromorphic Scales for Use in Water from Morning Dew and Elementary Model of Hydrogel Expansion Properties. (Masters Thesis). University of Colorado. Retrieved from https://scholar.colorado.edu/mats_gradetds/7
Chicago Manual of Style (16th Edition):
Margolis, Nate. “Hygromorphic Scales for Use in Water from Morning Dew and Elementary Model of Hydrogel Expansion Properties.” 2017. Masters Thesis, University of Colorado. Accessed November 22, 2019.
https://scholar.colorado.edu/mats_gradetds/7.
MLA Handbook (7th Edition):
Margolis, Nate. “Hygromorphic Scales for Use in Water from Morning Dew and Elementary Model of Hydrogel Expansion Properties.” 2017. Web. 22 Nov 2019.
Vancouver:
Margolis N. Hygromorphic Scales for Use in Water from Morning Dew and Elementary Model of Hydrogel Expansion Properties. [Internet] [Masters thesis]. University of Colorado; 2017. [cited 2019 Nov 22].
Available from: https://scholar.colorado.edu/mats_gradetds/7.
Council of Science Editors:
Margolis N. Hygromorphic Scales for Use in Water from Morning Dew and Elementary Model of Hydrogel Expansion Properties. [Masters Thesis]. University of Colorado; 2017. Available from: https://scholar.colorado.edu/mats_gradetds/7
University of Colorado
11.
Kan, Jian.
Blebbing of Hydrogel During Volume-Phase Transition.
Degree: MS, 2019, University of Colorado
URL: https://scholar.colorado.edu/mcen_gradetds/197
► Hydrogels are networks of polymer chains that are capable of absorbing solvent to become gel-like elastomeric materials. One common observation is the formation of…
(more)
▼ Hydrogels are networks of polymer chains that are capable of absorbing solvent to become gel-like elastomeric materials. One common observation is the formation of patterns on the stimuli-sensitive gel during the phase transition from swollen to shrunk phase. Our research investigates the mechanics behind gel blebbing; when a temperature-sensitive hydrogel encounters a sudden temperature change, multiple ballon-like bubbles can be seen forming on the gel surface during its shrinking phase. The previous researches established that the surface patterns are the result of an impermeable membrane forming on the surface, creating a surface layer which traps the solvent inside and causing bubbles to inflate. However, the details and kinetics of this inflation of blebs, as well as how neighboring blebs interact with each other, have not been fully understood. <a></a>In this paper, we first propose a single-bleb system, which explains how delamination and adhesion of its surface layer caused by the internal pressure change could affect the profile of a bleb. Next, we show how we can adapt this model to a multi-bleb system on a large scale surface, and how interactions between blebs could be simplified as “tunnels” transporting solvent between them. We also discuss how changing bath temperature and gel crosslink density could affect this profiles of blebbing according to our theory, then showing how this model aligns with data from our experiments using it{Polyacrylamide} hydrogels. We hope this research can provide more understanding of soft materials, such as soft robots and complex biological materials.
Advisors/Committee Members: Franck Vernerey, Jiangliang Xiao, Rong Long.
Subjects/Keywords: Blebbing; Hydrogel; Phase-transition; PNIPAm; Shrinking; Soft material; Mechanical Engineering
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APA (6th Edition):
Kan, J. (2019). Blebbing of Hydrogel During Volume-Phase Transition. (Masters Thesis). University of Colorado. Retrieved from https://scholar.colorado.edu/mcen_gradetds/197
Chicago Manual of Style (16th Edition):
Kan, Jian. “Blebbing of Hydrogel During Volume-Phase Transition.” 2019. Masters Thesis, University of Colorado. Accessed November 22, 2019.
https://scholar.colorado.edu/mcen_gradetds/197.
MLA Handbook (7th Edition):
Kan, Jian. “Blebbing of Hydrogel During Volume-Phase Transition.” 2019. Web. 22 Nov 2019.
Vancouver:
Kan J. Blebbing of Hydrogel During Volume-Phase Transition. [Internet] [Masters thesis]. University of Colorado; 2019. [cited 2019 Nov 22].
Available from: https://scholar.colorado.edu/mcen_gradetds/197.
Council of Science Editors:
Kan J. Blebbing of Hydrogel During Volume-Phase Transition. [Masters Thesis]. University of Colorado; 2019. Available from: https://scholar.colorado.edu/mcen_gradetds/197
University of Colorado
12.
Miao, Feng.
Mechanics of Interaction between Cell Membrane and a Rigid Substrate.
Degree: PhD, Mechanical Engineering, 2012, University of Colorado
URL: http://scholar.colorado.edu/mcen_gradetds/51
► Cells can response to various environmental stimuli, including chemicals, light, gravity, stiffness etc. Recent studies have showed that cells are sensitive to local substrate…
(more)
▼ Cells can response to various environmental stimuli, including chemicals, light, gravity, stiffness etc. Recent studies have showed that cells are sensitive to local substrate features like grooves, ridges and wells. Cell-substrate interaction is the gateway for the cell to feel the environmental stimuli, especially mechanical ones. However, the nature of how cells detect and respond to external topographic features is still unclear. In this paper, we presented a FEA based computational model for cell-substrate interactions. The cell-substrate adhesion is achieved by the forming of receptor-ligand bonds. Cell crawling and adhesion are studied with this model. We modeled a single cell's adhesion on rectangular and v-shaped rigid groove substrates. We found out that cell adhesion zone length is dependent on the groove height. The relationship between groove width and critical groove adhesion height is obtained on rectangular groove surface, and we also develop a theory to predict the critical adhesion height for a given groove width. On v-shaped groove substrates, we obtained the relationship of aspect ratio with groove height. We gained some insights about how cell adhesion can detect and respond to groove features through its mechanical interaction.
Advisors/Committee Members: H. Jerry Qi, Yifu Ding, Jianliang Xiao, Wei Tan, Franck Vernerey.
Subjects/Keywords: Cell adhesion; Cell alignment; Cell crawling; Cell mechanics; Contact guidance; FEA; Mechanical Engineering
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APA (6th Edition):
Miao, F. (2012). Mechanics of Interaction between Cell Membrane and a Rigid Substrate. (Doctoral Dissertation). University of Colorado. Retrieved from http://scholar.colorado.edu/mcen_gradetds/51
Chicago Manual of Style (16th Edition):
Miao, Feng. “Mechanics of Interaction between Cell Membrane and a Rigid Substrate.” 2012. Doctoral Dissertation, University of Colorado. Accessed November 22, 2019.
http://scholar.colorado.edu/mcen_gradetds/51.
MLA Handbook (7th Edition):
Miao, Feng. “Mechanics of Interaction between Cell Membrane and a Rigid Substrate.” 2012. Web. 22 Nov 2019.
Vancouver:
Miao F. Mechanics of Interaction between Cell Membrane and a Rigid Substrate. [Internet] [Doctoral dissertation]. University of Colorado; 2012. [cited 2019 Nov 22].
Available from: http://scholar.colorado.edu/mcen_gradetds/51.
Council of Science Editors:
Miao F. Mechanics of Interaction between Cell Membrane and a Rigid Substrate. [Doctoral Dissertation]. University of Colorado; 2012. Available from: http://scholar.colorado.edu/mcen_gradetds/51
University of Colorado
13.
Feaver, A.F. Amy.
Euclid's Algorithm in Multiquadratic Fields.
Degree: PhD, Mathematics, 2014, University of Colorado
URL: http://scholar.colorado.edu/math_gradetds/30
► In this thesis we find that all imaginary n-quadratic fields with n>3 have class number larger than 1 and therefore cannot be Euclidean. We…
(more)
▼ In this thesis we find that all imaginary
n-quadratic fields with
n>3 have class number larger than 1 and therefore cannot be Euclidean. We also examine imaginary triquadratic fields, presenting a complete list of 17 imaginary triquadratic fields with class number 1, and classifing many of them according to whether or not they are norm-Euclidean. We find that at least three of these fields are norm-Euclidean, and at least five are not.
Advisors/Committee Members: Katherine Stange, David Grant, Robert Tubbs, Eric Stade, Franck Vernerey.
Subjects/Keywords: Class Number; Euclidean Rings; Number Fields; Mathematics
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APA (6th Edition):
Feaver, A. F. A. (2014). Euclid's Algorithm in Multiquadratic Fields. (Doctoral Dissertation). University of Colorado. Retrieved from http://scholar.colorado.edu/math_gradetds/30
Chicago Manual of Style (16th Edition):
Feaver, A F Amy. “Euclid's Algorithm in Multiquadratic Fields.” 2014. Doctoral Dissertation, University of Colorado. Accessed November 22, 2019.
http://scholar.colorado.edu/math_gradetds/30.
MLA Handbook (7th Edition):
Feaver, A F Amy. “Euclid's Algorithm in Multiquadratic Fields.” 2014. Web. 22 Nov 2019.
Vancouver:
Feaver AFA. Euclid's Algorithm in Multiquadratic Fields. [Internet] [Doctoral dissertation]. University of Colorado; 2014. [cited 2019 Nov 22].
Available from: http://scholar.colorado.edu/math_gradetds/30.
Council of Science Editors:
Feaver AFA. Euclid's Algorithm in Multiquadratic Fields. [Doctoral Dissertation]. University of Colorado; 2014. Available from: http://scholar.colorado.edu/math_gradetds/30
University of Colorado
14.
Sliker, Levin John.
Experimental Analysis and Modeling of Robot-Tissue Contact Mechanics for In Vivo Mobility.
Degree: PhD, Mechanical Engineering, 2015, University of Colorado
URL: http://scholar.colorado.edu/mcen_gradetds/105
► Robotic mobility within the gastrointestinal (GI) tract is an intriguing concept, which has received wide attention from within the research community over the past…
(more)
▼ Robotic mobility within the gastrointestinal (GI) tract is an intriguing concept, which has received wide attention from within the research community over the past ten years. Capsule endoscopes (CEs) exist commercially, but lack an active mobility system, rendering them as passive devices. These passive devices are only capable of observational procedures, and are limited by the passive speed (dependent on intestinal peristalsis), inability to control orientation, and vulnerability to retention, requiring surgical removal in severe cases. Additionally, passive capsules take photos throughout their journey, resulting in a compilation of thousands of images, which can take the attending physician hours to review.
Due to these drawbacks, traditional endoscopes remain as the most popular intervention for GI related procedures. A traditional endoscope consists of a long flexible tube with a camera on the end of it. The tube usually has ports for tools, insufflation and irrigation. A user interface is located on the operator end of the scope, and can be manipulated to steer the tip of the scope. The scope is inserted through the oral or rectal orifice and is advanced by pushing the scope. As the scope is pushed, frictional forces can accumulate, resulting in advancement of the body of scope without advancement of the tip, termed looping. Looping results in distention of the bowel wall, pain for the patient and in rare cases perforation.
A robotic capsule endoscope (RCE) for oral endoscopies or robotic capsule colonoscope (RCC) for rectal colonoscopies is a capsular device (tethered or non-tethered) that propels itself through the GI tract. Self-propulsion could result in less looping, less pain for the patient, more ergonomic operation for the physician, control over capsule position and orientation, and the addition of diagnostic and therapeutic tools over existing passive CEs.
This work focuses on the contact mechanics of robot-tissue interaction in the GI tract with the goal of furthering the understanding of the physical problem so that more efficient and optimized mobility systems may be designed for RCEs and RCCs. This work also focuses on the design of an RCC which uses micro-patterned polydimethylsiloxane (PDMS) treads as a mobility method. The thesis is divided into nine chapters. Chapter 1 provides an overview of capsule and flexible endoscope technology as it relates to screening, diagnostics and therapy. A thorough overview of existing mobility methods (both commercial and experimental) for RCEs is also presented along with a background on micro-patterning for friction enhancement. Chapter 2 presents the qualitative analysis of micro-patterned treads through the development and in vivo testing of a series of two-wheeled robots as well as a testing apparatus for quantitatively evaluating micro-patterned robotic wheels in a static environment. Chapter 3 presents the development of a novel testing apparatus for evaluating robotic wheels in a dynamic environment, and results from data…
Advisors/Committee Members: Virginia Ferguson, Martin Dunn, Franck Vernerey, Kurt Maute, Jonathan Schoen.
Subjects/Keywords: Capsule endoscope; Contact mechanics; Gastrointestinal; Surgical robot; Tissue mechanics; Biomechanical Engineering; Biomedical Devices and Instrumentation; Robotics
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APA (6th Edition):
Sliker, L. J. (2015). Experimental Analysis and Modeling of Robot-Tissue Contact Mechanics for In Vivo Mobility. (Doctoral Dissertation). University of Colorado. Retrieved from http://scholar.colorado.edu/mcen_gradetds/105
Chicago Manual of Style (16th Edition):
Sliker, Levin John. “Experimental Analysis and Modeling of Robot-Tissue Contact Mechanics for In Vivo Mobility.” 2015. Doctoral Dissertation, University of Colorado. Accessed November 22, 2019.
http://scholar.colorado.edu/mcen_gradetds/105.
MLA Handbook (7th Edition):
Sliker, Levin John. “Experimental Analysis and Modeling of Robot-Tissue Contact Mechanics for In Vivo Mobility.” 2015. Web. 22 Nov 2019.
Vancouver:
Sliker LJ. Experimental Analysis and Modeling of Robot-Tissue Contact Mechanics for In Vivo Mobility. [Internet] [Doctoral dissertation]. University of Colorado; 2015. [cited 2019 Nov 22].
Available from: http://scholar.colorado.edu/mcen_gradetds/105.
Council of Science Editors:
Sliker LJ. Experimental Analysis and Modeling of Robot-Tissue Contact Mechanics for In Vivo Mobility. [Doctoral Dissertation]. University of Colorado; 2015. Available from: http://scholar.colorado.edu/mcen_gradetds/105
University of Colorado
15.
Lang, Christapher.
An XFEM Approach to Modeling Material Interface Uncertainty.
Degree: PhD, Aerospace Engineering Sciences, 2015, University of Colorado
URL: http://scholar.colorado.edu/asen_gradetds/111
► The focus of this research is uncertainty modeling for problems with random geometry. This dissertation develops a computational framework, based on the eXtended Finite…
(more)
▼ The focus of this research is uncertainty modeling for problems with random geometry. This dissertation develops a computational framework, based on the eXtended Finite Element Method (XFEM) and a Polynomial Chaos Expansion (PCE), for modeling heterogeneous materials with uncertain material interfaces. The uncertain geometry is characterized based on a finite set of random parameters, which requires a collection of measurement data or images. The XFEM is particularly useful for problems with changing interface geometries, as remeshing is avoided since a conforming mesh is not required. The XFEM is extended to the probability domain by a PCE based on the random parameters defining the uncertain geometry, and a random level set function implicitly defines the uncertain geometry. An intrusive PCE is implemented, which integrates the expansion within the deterministic model. Problems with continuous and discontinuous solutions at the material interface are solved, which utilize different enrichment functions. An accurate integration approach is introduced for the stochastic domain for both types of solutions. For problems with continuous solutions at the interface, a strategy for choosing a proper C0-continuous enrichment function is presented. A PCE is best suited to approximating a smooth behavior of the degrees of freedom, and this research shows that a proper C0-continuous enrichment function leads to a smooth behavior of the degrees of freedom when the spatial mesh is converged. To address solving problems with discontinuous solutions at the interface, an implementation of the Heaviside enriched XFEM is presented which provides a robust approach for handling complex interface configurations. A preconditioning scheme was developed to avoid ill-conditioning due to small intersected element volumes. The Heaviside enriched XFEM extended to the probability domain leads to a smooth behavior of the degrees of freedom regardless of the spatial mesh size. The C0-continuous enrichment requires simultaneous spatial and stochastic refinement to reduce the approximation error, while the Heaviside enrichment function leads to a solution that converges at low stochastic approximation orders for each spatial mesh size. Numerical examples include heat diffusion and linear elasticity for problems containing a single inclusion with random geometry.
Advisors/Committee Members: Kurt Maute, Alireza Doostan, Carlos Felippa, Franck Vernerey, Kim Bey.
Subjects/Keywords: Level Set Method; Polynomial Chaos; Uncertainty Analysis; XFEM; X-SFEM; Structures and Materials
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APA (6th Edition):
Lang, C. (2015). An XFEM Approach to Modeling Material Interface Uncertainty. (Doctoral Dissertation). University of Colorado. Retrieved from http://scholar.colorado.edu/asen_gradetds/111
Chicago Manual of Style (16th Edition):
Lang, Christapher. “An XFEM Approach to Modeling Material Interface Uncertainty.” 2015. Doctoral Dissertation, University of Colorado. Accessed November 22, 2019.
http://scholar.colorado.edu/asen_gradetds/111.
MLA Handbook (7th Edition):
Lang, Christapher. “An XFEM Approach to Modeling Material Interface Uncertainty.” 2015. Web. 22 Nov 2019.
Vancouver:
Lang C. An XFEM Approach to Modeling Material Interface Uncertainty. [Internet] [Doctoral dissertation]. University of Colorado; 2015. [cited 2019 Nov 22].
Available from: http://scholar.colorado.edu/asen_gradetds/111.
Council of Science Editors:
Lang C. An XFEM Approach to Modeling Material Interface Uncertainty. [Doctoral Dissertation]. University of Colorado; 2015. Available from: http://scholar.colorado.edu/asen_gradetds/111
University of Colorado
16.
Coffin, Peter B.
Levelset-XFEM Topology Optimization with Applications to Convective Heat Transfer.
Degree: PhD, Aerospace Engineering Sciences, 2015, University of Colorado
URL: http://scholar.colorado.edu/asen_gradetds/122
► Computational design optimization is a technique that provides designers with automated approaches to developing novel and non-intuitive optimal designs. Topology optimization is a subset…
(more)
▼ Computational design optimization is a technique that provides designers with automated approaches to developing novel and non-intuitive optimal designs. Topology optimization is a subset of design optimization that seeks to determine the optimal geometry allowing for topologic changes during the design process. The thesis focuses on the design of devices whose performance is dominated by convective heat transfer. Convective heat transfer is a process that results from the coupling between thermal fields and fluid motion. Frequently benefitting from complicated geometries, convective design problems are an ideal case for computational design optimization. Commonly used simple engineering models of convection like Newton's Law of Cooling rely on design dependent boundary conditions that may lie along immersed design edges. These boundary conditions are difficult to represent accurately with traditional density approaches for topology optimization. In this thesis Level Set Method (LSM) and the eXtended Finite Element Methods (XFEM) are developed to handle convective design problems to ensure crisp resolution of design boundaries for accurate physical modeling. The LSM is used to provide a precise definition of geometric boundaries. Here the explicit LSM is used, which updates the parameterized Level Set Field (LSF) via Nonlinear Programming methods (NLP). The XFEM is incorporated to provide for crisp resolution of the LSM geometry within the discretization of the governing equations. With accurate resolution of simplified convection boundary conditions, complicated, potentially unphysical geometries are developed. To overcome this issue this thesis develops new regularization approaches for explicit LSMs. To enforce a minimum feature size a new measure is developed that identifies violations of the minimum feature size. To demonstrate the applicability of the LSXFEM approach we study more complicated, coupled problems where the fluid motion is driven by buoyancy forces. The natural convection model is applied to both 2D and 3D steady-state design problems and 2D transient problems.
Advisors/Committee Members: Kurt Maute, Alireza Doostan, Mahmoud Hussein, John Evans, Franck Vernerey.
Subjects/Keywords: level set method; cooling and heating devices; steady state; Aerospace Engineering; Mechanical Engineering
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APA (6th Edition):
Coffin, P. B. (2015). Levelset-XFEM Topology Optimization with Applications to Convective Heat Transfer. (Doctoral Dissertation). University of Colorado. Retrieved from http://scholar.colorado.edu/asen_gradetds/122
Chicago Manual of Style (16th Edition):
Coffin, Peter B. “Levelset-XFEM Topology Optimization with Applications to Convective Heat Transfer.” 2015. Doctoral Dissertation, University of Colorado. Accessed November 22, 2019.
http://scholar.colorado.edu/asen_gradetds/122.
MLA Handbook (7th Edition):
Coffin, Peter B. “Levelset-XFEM Topology Optimization with Applications to Convective Heat Transfer.” 2015. Web. 22 Nov 2019.
Vancouver:
Coffin PB. Levelset-XFEM Topology Optimization with Applications to Convective Heat Transfer. [Internet] [Doctoral dissertation]. University of Colorado; 2015. [cited 2019 Nov 22].
Available from: http://scholar.colorado.edu/asen_gradetds/122.
Council of Science Editors:
Coffin PB. Levelset-XFEM Topology Optimization with Applications to Convective Heat Transfer. [Doctoral Dissertation]. University of Colorado; 2015. Available from: http://scholar.colorado.edu/asen_gradetds/122
University of Colorado
17.
Nguyen, Lan T.
Confined Masonry: Theoretical Fundamentals, Experimental Test, Finite Element Models, and Future Uses.
Degree: PhD, 2014, University of Colorado
URL: https://scholar.colorado.edu/cven_gradetds/436
► Inspired from the MS thesis that investigated the underlying relationship between the implicit level of risk accepted for natural hazards and the level of…
(more)
▼ Inspired from the MS thesis that investigated the underlying relationship between the implicit level of risk accepted for natural hazards and the level of economic, social and political development of Haiti, a developing country, this dissertation focuses structurally on the use of low-rise confined masonry (CM) buildings in natural hazard consideration areas. The research emphasizes the responses of the CM shear wall structure as a whole, as well as the material conditions in detail. Key findings are presented from experimental tests, computational modeling procedures, analytical results, and reliability analysis for CM structures followed with the summary of the behavior of CM subjected to in-plane loading. This project covers behavior and reliability of CM structures subject to earthquake loading and enables informed decisions about risk in earthquake engineering design, including assessment of existing structures and retrofit design. Through experimental tests, development of a finite element analysis algorithm, and reliability analysis, this study found that structural integrity of a CM system is especially sensitive to the compression confining the wall from the surrounding concrete tie-frame and the materials used in the masonry panel. These parameters are addressed through the use of micro and macro modeling concepts, with the final model based on a macro-modeling strategy built by a force-deformation envelope curve prediction, and analysis that shows the structural safety aspect of CM in a recommended reliability index. Unreinforced masonry contributes significantly to the number of structural failures, value of economic losses, and business disruption associated with natural hazards in the U.S. This study is an initial step towards providing the Masonry Standards Joint Committee (MSJC) with information on the CM system and build guidelines as a variation of the masonry infill system. For regular masonry buildings, this study provides a mechanism to improve the consistency and efficiency of building codes through explicit evaluation of design provisions. This research outcome is applicable to a large number of unreinforced masonry structures throughout the world, and as extension ranging from the vulnerability of lifeline system to historical preservation of masonry structures.
Advisors/Committee Members: Ross Corotis, Franck Vernerey, Petros Sideris, Guido Camata, Michael Schuller.
Subjects/Keywords: confined masonry; experimental; finite element; reliability; shear wall; testing; Civil Engineering; Engineering Mechanics
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APA (6th Edition):
Nguyen, L. T. (2014). Confined Masonry: Theoretical Fundamentals, Experimental Test, Finite Element Models, and Future Uses. (Doctoral Dissertation). University of Colorado. Retrieved from https://scholar.colorado.edu/cven_gradetds/436
Chicago Manual of Style (16th Edition):
Nguyen, Lan T. “Confined Masonry: Theoretical Fundamentals, Experimental Test, Finite Element Models, and Future Uses.” 2014. Doctoral Dissertation, University of Colorado. Accessed November 22, 2019.
https://scholar.colorado.edu/cven_gradetds/436.
MLA Handbook (7th Edition):
Nguyen, Lan T. “Confined Masonry: Theoretical Fundamentals, Experimental Test, Finite Element Models, and Future Uses.” 2014. Web. 22 Nov 2019.
Vancouver:
Nguyen LT. Confined Masonry: Theoretical Fundamentals, Experimental Test, Finite Element Models, and Future Uses. [Internet] [Doctoral dissertation]. University of Colorado; 2014. [cited 2019 Nov 22].
Available from: https://scholar.colorado.edu/cven_gradetds/436.
Council of Science Editors:
Nguyen LT. Confined Masonry: Theoretical Fundamentals, Experimental Test, Finite Element Models, and Future Uses. [Doctoral Dissertation]. University of Colorado; 2014. Available from: https://scholar.colorado.edu/cven_gradetds/436
University of Colorado
18.
Engvall, Luke H.
Geometrically Exact and Analysis Suitable Mesh Generation Using Rational Bernstein–Bezier Elements.
Degree: PhD, 2018, University of Colorado
URL: https://scholar.colorado.edu/mcen_gradetds/170
► This dissertation presents two novel contributions to the fields of isogeometric analysis and <i>p</i>-version finite elements. First, we present a framework for geometrically exact…
(more)
▼ This dissertation presents two novel contributions to the fields of isogeometric analysis and <i>p</i>-version finite elements. First, we present a framework for geometrically exact volumetric mesh generation. By leveraging ideas from both traditional mesh generation as well as isogeometric analysis, we develop a framework for volumetric mesh generation using rational Bernstein – Bézier discretizations. Within this framework, we provide a set of easily verifiable sufficient conditions for guaranteeing that a mesh will be geometrically exact. Second, we develop a complete theory of mesh quality for these rational Bernstein – Bézier elements. From this, we derive a set of easily computable mesh quality metrics for verifying that a rational Bernstein – Bézier discretization will be analysis suitable.
Advisors/Committee Members: John A. Evans, Peter Hamlington, Kenneth Jansen, Daven Henze, Franck Vernerey.
Subjects/Keywords: curvilinear mesh generation; higher-order finite elements; isogeometric analysis; mesh generation; discretization; Engineering; Mechanical Engineering
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APA (6th Edition):
Engvall, L. H. (2018). Geometrically Exact and Analysis Suitable Mesh Generation Using Rational Bernstein–Bezier Elements. (Doctoral Dissertation). University of Colorado. Retrieved from https://scholar.colorado.edu/mcen_gradetds/170
Chicago Manual of Style (16th Edition):
Engvall, Luke H. “Geometrically Exact and Analysis Suitable Mesh Generation Using Rational Bernstein–Bezier Elements.” 2018. Doctoral Dissertation, University of Colorado. Accessed November 22, 2019.
https://scholar.colorado.edu/mcen_gradetds/170.
MLA Handbook (7th Edition):
Engvall, Luke H. “Geometrically Exact and Analysis Suitable Mesh Generation Using Rational Bernstein–Bezier Elements.” 2018. Web. 22 Nov 2019.
Vancouver:
Engvall LH. Geometrically Exact and Analysis Suitable Mesh Generation Using Rational Bernstein–Bezier Elements. [Internet] [Doctoral dissertation]. University of Colorado; 2018. [cited 2019 Nov 22].
Available from: https://scholar.colorado.edu/mcen_gradetds/170.
Council of Science Editors:
Engvall LH. Geometrically Exact and Analysis Suitable Mesh Generation Using Rational Bernstein–Bezier Elements. [Doctoral Dissertation]. University of Colorado; 2018. Available from: https://scholar.colorado.edu/mcen_gradetds/170
University of Colorado
19.
Liang, Yu-chang.
Experimental Study and Theoretical Modeling of Recycled Aggregate Concrete and Evaluation of Long-Term Performance of Reinforced Concrete Bridge Decks.
Degree: PhD, 2012, University of Colorado
URL: https://scholar.colorado.edu/cven_gradetds/317
► This dissertation covers two themes: one for experimental and theoretical studies of recycled aggregate concrete (RAC) and the other for the performance evaluation of…
(more)
▼ This dissertation covers two themes: one for experimental and theoretical studies of recycled aggregate concrete (RAC) and the other for the performance evaluation of chemical sealers applied to reinforced concrete (RC) bridge decks. For the first theme, the research has found that a better mixing approach, better water to cement ratio, and more appropriate surface treatments can improve RAC's mechanical properties. We further checked its durability properties. Also, this research has developed a theoretical model for analyzing and predicting various properties of RACs such as bulk modulus, volume fraction, shear modulus, and shrinkage strain. One of the durability properties, drying shrinkage, was used to modify this multiscale and multiphase model. The second theme includes: (1) discovering the corrosion initiation time of the rebar embedded in RC bridge decks attacked by the chloride ions from deicers; (2) giving the rankings of four popular sealer products applied to RC bridge decks based on the results of long-term performance monitoring; and (3) deriving diffusion equation models in comparisons with field performance measurements and combining those with concrete composite damage model.
Advisors/Committee Members: Yunping Xi, Ross Corotis, Mettupalayam Siva, Franck Vernerey, Kevin Rens.
Subjects/Keywords: composite damage model; mixing approach; multiscale and multiphase model; surface treatment; Architecture; Civil Engineering
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APA (6th Edition):
Liang, Y. (2012). Experimental Study and Theoretical Modeling of Recycled Aggregate Concrete and Evaluation of Long-Term Performance of Reinforced Concrete Bridge Decks. (Doctoral Dissertation). University of Colorado. Retrieved from https://scholar.colorado.edu/cven_gradetds/317
Chicago Manual of Style (16th Edition):
Liang, Yu-chang. “Experimental Study and Theoretical Modeling of Recycled Aggregate Concrete and Evaluation of Long-Term Performance of Reinforced Concrete Bridge Decks.” 2012. Doctoral Dissertation, University of Colorado. Accessed November 22, 2019.
https://scholar.colorado.edu/cven_gradetds/317.
MLA Handbook (7th Edition):
Liang, Yu-chang. “Experimental Study and Theoretical Modeling of Recycled Aggregate Concrete and Evaluation of Long-Term Performance of Reinforced Concrete Bridge Decks.” 2012. Web. 22 Nov 2019.
Vancouver:
Liang Y. Experimental Study and Theoretical Modeling of Recycled Aggregate Concrete and Evaluation of Long-Term Performance of Reinforced Concrete Bridge Decks. [Internet] [Doctoral dissertation]. University of Colorado; 2012. [cited 2019 Nov 22].
Available from: https://scholar.colorado.edu/cven_gradetds/317.
Council of Science Editors:
Liang Y. Experimental Study and Theoretical Modeling of Recycled Aggregate Concrete and Evaluation of Long-Term Performance of Reinforced Concrete Bridge Decks. [Doctoral Dissertation]. University of Colorado; 2012. Available from: https://scholar.colorado.edu/cven_gradetds/317
University of Colorado
20.
Zou, Zhanan.
Bio-Mimetic Smart System Functioning Like Natural Skin and Muscle.
Degree: PhD, 2019, University of Colorado
URL: https://scholar.colorado.edu/mcen_gradetds/193
► Soft machines, or soft robotics, are emerging technologies bringing many exciting prospects for the coming future. Creating soft machines with biomimetic functions is of key…
(more)
▼ Soft machines, or soft robotics, are emerging technologies bringing many exciting prospects for the coming future. Creating soft machines with biomimetic functions is of key importance for applications in bettering human life and creating more complex robotic systems. Various mechanisms have been adopted to mimic natural tactile sense, tough, muscular motion, and even artificial intelligence. Among these, developing a bio-mimetic system capable of self-healing and degradation that behaves like a muscular hydrostat is appealing for soft robotics. This thesis will mainly focus on developing both artificial skin and artificial muscles that can self-heal, be recycled, and function like biological tissue. To develop a biomimetic artificial skin, we adopted an imine-bonded polymer as the main component, and embedded silver nanoparticles as well as liquid metals to create conductive components. Our artificial skin is capable of re-healing and recycling, and can be mounted to a complex 3D surface without introducing damage and strains. Such artificial skin, at the same time, can sense pressure and temperature change, flow across the surface, and humidity change in the atmosphere. Recyclability enables this platform to not only serve as an artificial skin, but also for other electronics applications. The artificial muscles were also developed for this project based on a recently invented Liquid Crystal Elastomer, whose behavior is most similar to that of natural muscles. To achieve large actuation strains, a fast response, and small scale local controlling, a Liquid Metal was introduced for stimulating the artificial muscle. Over 100% linear contracting strain was realized based on such a combination, which is greater than that of natural muscles. Bending and twisting deformation were also realized easily on such system. To further demonstrate the advantages of our artificial muscle, we integrated it into other passive soft elastomers like Ecoflex to mimic the camouflage behavior of cephalopods.
Advisors/Committee Members: Jianliang Xiao, Gregory Whiting, Wei Zhang, Rong Long, Franck Vernerey.
Subjects/Keywords: artificial skin; artificial muscle; Imine-bonding; liquid crystal elastomer; soft robotics; Mechanical Engineering
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APA (6th Edition):
Zou, Z. (2019). Bio-Mimetic Smart System Functioning Like Natural Skin and Muscle. (Doctoral Dissertation). University of Colorado. Retrieved from https://scholar.colorado.edu/mcen_gradetds/193
Chicago Manual of Style (16th Edition):
Zou, Zhanan. “Bio-Mimetic Smart System Functioning Like Natural Skin and Muscle.” 2019. Doctoral Dissertation, University of Colorado. Accessed November 22, 2019.
https://scholar.colorado.edu/mcen_gradetds/193.
MLA Handbook (7th Edition):
Zou, Zhanan. “Bio-Mimetic Smart System Functioning Like Natural Skin and Muscle.” 2019. Web. 22 Nov 2019.
Vancouver:
Zou Z. Bio-Mimetic Smart System Functioning Like Natural Skin and Muscle. [Internet] [Doctoral dissertation]. University of Colorado; 2019. [cited 2019 Nov 22].
Available from: https://scholar.colorado.edu/mcen_gradetds/193.
Council of Science Editors:
Zou Z. Bio-Mimetic Smart System Functioning Like Natural Skin and Muscle. [Doctoral Dissertation]. University of Colorado; 2019. Available from: https://scholar.colorado.edu/mcen_gradetds/193
University of Colorado
21.
Shahabi, Farhad.
Finite Strain Micromorphic Elasticity, Elastoplasticity, and Dynamics for Multiscale Finite Element Analysis.
Degree: PhD, 2017, University of Colorado
URL: https://scholar.colorado.edu/cven_gradetds/96
► This study stands as an attempt to consider the micro-structure of materials in a continuum framework by the aid of micromorphic continuum theory in the…
(more)
▼ This study stands as an attempt to consider the micro-structure of materials in a continuum framework by the aid of micromorphic continuum theory in the sense of Eringen. Since classical continuum mechanics do not account for the micro-structural characteristics of materials, they cannot be used to address the macroscopic mechanical response of all micro-structured materials. In the “representative volume element (RVE)” based methods, classical continuum mechanics may be applied to analyze mechanical deformation and stresses of materials at the relevant micro-structural length-scale (such as grains of a polycrystalline metal, or sand, or metal matrix composite, etc), but when applying standard homogenization methods, such lower length scale effects get smeared out at the continuum scale. The micromorphic continuum theory provides the ability to incorporate the micro-structural effects into the macroscopic mechanical behavior. Therefore, the micromorphic continuum is a tool for a higher resolution multi-scale material modeling through capturing the material's micro-structural physics via bridging to the direct numerical simulations (DNS) at the lower length scale. In the micromorphic continuum theory of Eringen, the fundamental assumption is that the material is made of “micro-elements” in such a way that the classical continuum mechanics balance equations and thermodynamics are valid within a micro-element. Note that micro-elements represent the material's micro-structure in a micromorphic continuum. The micro-element deformation with respect to the centroid of a macroscopic continuum point is governed by an independent micro-deformation tensor χ which adds 9 additional degrees of freedom to the continuum model. The micromorphic additional degrees of freedom represent micro-stretch, micro-shear, and micro-rotation of the micro-elements. The macroscopic deformation (macro-element deformation) in the micromorphic continuum is handled through the deformation gradient tensor F. If the hypothesis of micromorphic continuum works, in a multi-scale modeling framework, assuming proper constitutive models can be formulated, and material parameters calibrated, micromorphic continuum theory may fill the gap between the RVE-micro-structural-length-scale models and the macroscopic continuum scale. The advantage of using micromorphic continuum is that it provides a chance of linking the macroscopic model to the lower length scale simulations (DNS) and reducing the computational cost by switching from DNS to the macro-scale finite element analysis or other numerical methods at the continuum scale. The linking is done through defining the overlap coupling region between the lower length scale analysis and micromorphic continuum to calibrate the material parameters and the micromorphic continuum model degrees of freedom. Therefore, in the framework of multi-scale modeling, micromorphic continuum can be used as a filter on top of the DNS simulations to capture underlying length scale and better inform the macroscopic model. This is…
Advisors/Committee Members: Richard A. Regueiro, Ronald Y. S. Pak, John A. Evans, Franck Vernerey, Jeong-Hoon Song.
Subjects/Keywords: Dynamics; Elastoplasticity; Finite Element Analysis; Large Deformation; Micromorphic Continuum; Micropolar Continuum; Engineering Mechanics; Mechanical Engineering
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APA (6th Edition):
Shahabi, F. (2017). Finite Strain Micromorphic Elasticity, Elastoplasticity, and Dynamics for Multiscale Finite Element Analysis. (Doctoral Dissertation). University of Colorado. Retrieved from https://scholar.colorado.edu/cven_gradetds/96
Chicago Manual of Style (16th Edition):
Shahabi, Farhad. “Finite Strain Micromorphic Elasticity, Elastoplasticity, and Dynamics for Multiscale Finite Element Analysis.” 2017. Doctoral Dissertation, University of Colorado. Accessed November 22, 2019.
https://scholar.colorado.edu/cven_gradetds/96.
MLA Handbook (7th Edition):
Shahabi, Farhad. “Finite Strain Micromorphic Elasticity, Elastoplasticity, and Dynamics for Multiscale Finite Element Analysis.” 2017. Web. 22 Nov 2019.
Vancouver:
Shahabi F. Finite Strain Micromorphic Elasticity, Elastoplasticity, and Dynamics for Multiscale Finite Element Analysis. [Internet] [Doctoral dissertation]. University of Colorado; 2017. [cited 2019 Nov 22].
Available from: https://scholar.colorado.edu/cven_gradetds/96.
Council of Science Editors:
Shahabi F. Finite Strain Micromorphic Elasticity, Elastoplasticity, and Dynamics for Multiscale Finite Element Analysis. [Doctoral Dissertation]. University of Colorado; 2017. Available from: https://scholar.colorado.edu/cven_gradetds/96
University of Colorado
22.
Stender, Michael Eric.
Osteochondral Tissue Modeling of Damage, Poroelastcity, and Remodeling in Osteoarthritis.
Degree: PhD, Mechanical Engineering, 2015, University of Colorado
URL: http://scholar.colorado.edu/mcen_gradetds/108
► Arthritis is the most costly disability in the United States annually incurring billions of dollars in treatment costs and lost wages. Osteoarthritis, a classification…
(more)
▼ Arthritis is the most costly disability in the United States annually incurring billions of dollars in treatment costs and lost wages. Osteoarthritis, a classification of arthritis, affects articulating synovial joints (e.g., hip, knee, shoulder) and results in moderate to severe pain. In extreme cases, osteoarthritis causes loss of joint mobility. Presently, there is not a clear understanding of how osteoarthritis initiates, propagates, and ultimately degrades the mechanics of healthy synovial joints. This doctoral work uses computational modeling techniques and finite element analysis to elucidate the initiation and evolution of osteoarthritis with the ultimate goal of contributing to improved clinical treatments. The first project was to develop a damage model for articular cartilage, the tissue lining the contact surfaces of synovial joints. An articular cartilage damage model was developed with the capability to model 3-D fully anisotropic damage including complete tissue tensile failure and progressive damage to critical structural elements. The second project was to develop a model of the complete bone-cartilage unit including poroelastic material behavior (i.e., solid-fluid interactions during loading of porous materials). This model demonstrated differences in poroelastic behavior between normal and osteoarthritic joint tissues and suggested that alterations in fluid flow patterns as a result of osteoarthritis may lead to increasingly diminished joint health. The final project integrated the first and second projects with a previously developed bone remodeling algorithm to study the initiation and progression behavior of osteoarthritis. This model showed that while articular cartilage damage and bone remodeling may initially as independent processes, they likely become interdependent as osteoarthritis progresses. Overall, these results improve our understanding of the in vivo mechanics of osteoarthritis initiation and progression and may guide future experimental and computational studies with the ultimate goal of improving clinical outcomes for osteoarthritis patients.
Advisors/Committee Members: Virginia L. Ferguson, Richard A. Reguerio, Dana R. Carpenter, Rong Long, Franck Vernerey.
Subjects/Keywords: bone; cartilage; damage; finite element; osteoarthritis; poroelasticity; Biomechanical Engineering; Biomechanics and Biotransport
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APA (6th Edition):
Stender, M. E. (2015). Osteochondral Tissue Modeling of Damage, Poroelastcity, and Remodeling in Osteoarthritis. (Doctoral Dissertation). University of Colorado. Retrieved from http://scholar.colorado.edu/mcen_gradetds/108
Chicago Manual of Style (16th Edition):
Stender, Michael Eric. “Osteochondral Tissue Modeling of Damage, Poroelastcity, and Remodeling in Osteoarthritis.” 2015. Doctoral Dissertation, University of Colorado. Accessed November 22, 2019.
http://scholar.colorado.edu/mcen_gradetds/108.
MLA Handbook (7th Edition):
Stender, Michael Eric. “Osteochondral Tissue Modeling of Damage, Poroelastcity, and Remodeling in Osteoarthritis.” 2015. Web. 22 Nov 2019.
Vancouver:
Stender ME. Osteochondral Tissue Modeling of Damage, Poroelastcity, and Remodeling in Osteoarthritis. [Internet] [Doctoral dissertation]. University of Colorado; 2015. [cited 2019 Nov 22].
Available from: http://scholar.colorado.edu/mcen_gradetds/108.
Council of Science Editors:
Stender ME. Osteochondral Tissue Modeling of Damage, Poroelastcity, and Remodeling in Osteoarthritis. [Doctoral Dissertation]. University of Colorado; 2015. Available from: http://scholar.colorado.edu/mcen_gradetds/108
University of Colorado
23.
Blackwell, Robert Allen.
Modeling Cytoskeletal Active Matter Systems.
Degree: PhD, Physics, 2016, University of Colorado
URL: http://scholar.colorado.edu/phys_gradetds/162
► Active networks of filamentous proteins and crosslinking motor proteins play a critical role in many important cellular processes. One of the most important microtubule-motor…
(more)
▼ Active networks of filamentous proteins and crosslinking motor proteins play a critical role in many important cellular processes. One of the most important microtubule-motor protein assemblies is the mitotic spindle, a self-organized active liquid-crystalline structure that forms during cell division and that ultimately separates chromosomes into two daughter cells. Although the spindle has been intensively studied for decades, the physical principles that govern its self-organization and function remain mysterious. To evolve a better understanding of spindle formation, structure, and dynamics, I investigate course-grained models of active liquid-crystalline networks composed of microtubules, modeled as hard spherocylinders, in diffusive equilibrium with a reservoir of active crosslinks, modeled as hookean springs that can adsorb to microtubules and and translocate at finite velocity along the microtubule axis. This model is investigated using a combination of brownian dynamics and kinetic monte carlo simulation. I have further refined this model to simulate spindle formation and kinetochore capture in the fission yeast S. pombe. I then make predictions for experimentally realizable perturbations in motor protein presence and function in S. pombe.
Advisors/Committee Members: Matthew A. Glaser, Meredith D. Betterton, Noel Clark, Leo Radzihovsky, Franck Vernerey.
Subjects/Keywords: brownian dynamics; cytoskeleton; kinetic monte carlo; motor proteins; pombe; spindle; Biophysics; Condensed Matter Physics
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APA (6th Edition):
Blackwell, R. A. (2016). Modeling Cytoskeletal Active Matter Systems. (Doctoral Dissertation). University of Colorado. Retrieved from http://scholar.colorado.edu/phys_gradetds/162
Chicago Manual of Style (16th Edition):
Blackwell, Robert Allen. “Modeling Cytoskeletal Active Matter Systems.” 2016. Doctoral Dissertation, University of Colorado. Accessed November 22, 2019.
http://scholar.colorado.edu/phys_gradetds/162.
MLA Handbook (7th Edition):
Blackwell, Robert Allen. “Modeling Cytoskeletal Active Matter Systems.” 2016. Web. 22 Nov 2019.
Vancouver:
Blackwell RA. Modeling Cytoskeletal Active Matter Systems. [Internet] [Doctoral dissertation]. University of Colorado; 2016. [cited 2019 Nov 22].
Available from: http://scholar.colorado.edu/phys_gradetds/162.
Council of Science Editors:
Blackwell RA. Modeling Cytoskeletal Active Matter Systems. [Doctoral Dissertation]. University of Colorado; 2016. Available from: http://scholar.colorado.edu/phys_gradetds/162
University of Colorado
24.
Na, Okpin.
Parallel Computational Modeling and Experimental Studies on Durability of Cementitious Materials and Structures.
Degree: PhD, 2011, University of Colorado
URL: https://scholar.colorado.edu/cven_gradetds/218
► In order to predict long-term performance of reinforced concrete structures, a clear understanding of deterioration mechanism in portland cement concrete is a crucial issue.…
(more)
▼ In order to predict long-term performance of reinforced concrete structures, a clear understanding of deterioration mechanism in portland cement concrete is a crucial issue. There are several deterioration mechanisms, and chloride-induced corrosion of reinforcement is an important one. The transport rates of chloride and other ions from deicing salts determine the time at which the corrosion of reinforcement starts, which is an important parameter for evaluating the durability of the structure. The main objective of this thesis is to develop a generalized framework based on parallel computing technique to analyze the durability performance of reinforced concrete structures with an emphasis on the coupled transport processes of chloride and other species from deicing salts in non-saturated concrete under ambient temperature.
The generalized framework for the coupled transport processes is based on a modified Nernst-Planck equation, which includes the coupling effects of both moisture transfer and thermal conduction in concrete. For the parallel implementation, an overlapping addictive Schwarz method as preconditioner is used. In order to predict numerically the transport processes in a large-scale structure with a realistic boundary condition, various chloride concentrations and environmental humidity models. The prediction by the theoretical models and parallel algorithm agree quite well with available experimental data. In addition to the theoretical and numerical studies, experimental studies are conducted to investigate and improve various properties of sustainable cementitious materials made of rubber particles from waste tires, including compressive strength, bond strength, chloride permeability resistance, drying shrinkage, and freeze-thaw resistance.
Advisors/Committee Members: Yunping Xi, Xial Chuan Cai, Mettupalayam V. Sivaselvan, Franck Vernerey, Richard A. Regueiro.
Subjects/Keywords: chloride diffusion; chloride induced corrosion; domain decomposition method; durability of concrete; finite element method; parallel computiation; Civil Engineering
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APA (6th Edition):
Na, O. (2011). Parallel Computational Modeling and Experimental Studies on Durability of Cementitious Materials and Structures. (Doctoral Dissertation). University of Colorado. Retrieved from https://scholar.colorado.edu/cven_gradetds/218
Chicago Manual of Style (16th Edition):
Na, Okpin. “Parallel Computational Modeling and Experimental Studies on Durability of Cementitious Materials and Structures.” 2011. Doctoral Dissertation, University of Colorado. Accessed November 22, 2019.
https://scholar.colorado.edu/cven_gradetds/218.
MLA Handbook (7th Edition):
Na, Okpin. “Parallel Computational Modeling and Experimental Studies on Durability of Cementitious Materials and Structures.” 2011. Web. 22 Nov 2019.
Vancouver:
Na O. Parallel Computational Modeling and Experimental Studies on Durability of Cementitious Materials and Structures. [Internet] [Doctoral dissertation]. University of Colorado; 2011. [cited 2019 Nov 22].
Available from: https://scholar.colorado.edu/cven_gradetds/218.
Council of Science Editors:
Na O. Parallel Computational Modeling and Experimental Studies on Durability of Cementitious Materials and Structures. [Doctoral Dissertation]. University of Colorado; 2011. Available from: https://scholar.colorado.edu/cven_gradetds/218
University of Colorado
25.
Musiket, Kamtornkiat.
Mechanical Properties of Recycled Aggregate Concrete Under Different Loading Rates.
Degree: PhD, 2014, University of Colorado
URL: https://scholar.colorado.edu/cven_gradetds/123
► This dissertation is an extensive experimental, theoretical, and numerical study on mechanical properties of Recycled Aggregate Concrete (RAC). Fracture properties of RAC at different loading…
(more)
▼ This dissertation is an extensive experimental, theoretical, and numerical study on mechanical properties of Recycled Aggregate Concrete (RAC). Fracture properties of RAC at different loading rates vary comparing with those obtained at quasi-static rate. The present experimental results showed that the brittleness of RAC decreases and R-curve increases corresponding to higher strain rates. Based on the present experimental results and the results in literature, a model was proposed for the fracture energy release rate of RAC at various strain rates. The modulus of elasticity of RAC at different loading rates was also studied. A similar trend with normal concrete was found, that is, the modulus of elasticity increases with increasing strain rates. Viscoelastic theory was used to develop a model for predicting the elastic modulus of RAC at various loading rates. Differing from previous empirical models, the viscoelastic model can cover any selected range of strain rates and more importantly it can distinguish the contribution of the material stiffness in each decade (each order of magnitude of the rate) within the selected loading range. The model predictions were in good agreement with test data. Although the compressive strength and modulus of elasticity of RAC increase quite significantly with increasing loading rate, the increase of compressive strains at peak load was found to be less significant than the strength and stiffness. Recycled aggregate is often treated by a surface coating to reduce its moisture absorbing capacity and to increase the bond between the residual and the new cement paste. To consider this special composition feature of recycled aggregates, a multiphase model based on composite mechanics was proposed to determine the modulus of elasticity of RAC with different strengths and volume fractions of residual cement paste and coating materials. This multiphase model was further integrated with the viscoelastic model such that the generalized comprehensive model, called Strain Rate Multiphase Model (SRMM), can be used to predict stiffness of any multiphase composite material including RAC at different strain rates. The SRMM was validated using the commercial finite element software ABAQUS on crack propagation of RAC notched-beams. The numerical simulations were compared with the present test data, and they agreed reasonably well. Therefore, SRMM is a versatile and reliable model to evaluate the modulus of elasticity of composite materials such as RAC subjected to various loading rates. The experimental and theoretical approaches developed in this dissertation paved the way for further investigation of other properties of composite materials such as RAC under different loading rates.
Advisors/Committee Members: Yunping Xi, Franck Vernerey, Abbie Liel, Mija Helena. Hubler, Wil V. Srubar III.
Subjects/Keywords: elastic modulus of concrete; extended finite element; multiphase composite model; recycled aggregate concrete; strain rate effect; viscoelastic model; Civil Engineering
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APA ·
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APA (6th Edition):
Musiket, K. (2014). Mechanical Properties of Recycled Aggregate Concrete Under Different Loading Rates. (Doctoral Dissertation). University of Colorado. Retrieved from https://scholar.colorado.edu/cven_gradetds/123
Chicago Manual of Style (16th Edition):
Musiket, Kamtornkiat. “Mechanical Properties of Recycled Aggregate Concrete Under Different Loading Rates.” 2014. Doctoral Dissertation, University of Colorado. Accessed November 22, 2019.
https://scholar.colorado.edu/cven_gradetds/123.
MLA Handbook (7th Edition):
Musiket, Kamtornkiat. “Mechanical Properties of Recycled Aggregate Concrete Under Different Loading Rates.” 2014. Web. 22 Nov 2019.
Vancouver:
Musiket K. Mechanical Properties of Recycled Aggregate Concrete Under Different Loading Rates. [Internet] [Doctoral dissertation]. University of Colorado; 2014. [cited 2019 Nov 22].
Available from: https://scholar.colorado.edu/cven_gradetds/123.
Council of Science Editors:
Musiket K. Mechanical Properties of Recycled Aggregate Concrete Under Different Loading Rates. [Doctoral Dissertation]. University of Colorado; 2014. Available from: https://scholar.colorado.edu/cven_gradetds/123
University of Colorado
26.
Sharma, Ashesh.
Advances in Design and Optimization Using Immersed Boundary Methods.
Degree: PhD, 2017, University of Colorado
URL: https://scholar.colorado.edu/asen_gradetds/190
► This thesis is concerned with topology optimization which provides engineers with a systematic approach to optimize the layout and geometry of a structure against…
(more)
▼ This thesis is concerned with topology optimization which provides engineers with a systematic approach to optimize the layout and geometry of a structure against various design criteria. Traditional topology optimization uses density-based methods to capture topological changes in geometry. Density-based methods describe a structural layout using artificial elemental densities. To obtain a good resolution of the geometry, fine meshes are required. This however leads to large computational costs in 3D. Using coarser but practical meshes results in blurred structural boundaries and unreliable prediction of physical response along those boundaries. Using immersed boundary methods instead, such as the extended finite element method (XFEM), alleviates these issues. The XFEM provides clear description of the geometry, and approximation of the physical response along boundaries has been shown to converge to the approximation using body-fitted meshes. This thesis focuses on the use of XFEM for topology optimization. Design geometry in this thesis is tracked precisely using the level set method (LSM). The LSM-XFEM approach is used to solve variety of multiphysics design and optimization problems. However, being a relatively new field of study the LSM-XFEM approach continues to pose many interesting challenges limiting its applicability to topology optimization. The goal of this thesis is to present advances made towards making LSM-XFEM more viable and reliable for design and optimization of multiphysics problems. Specifically, i) The numerical behavior of XFEM-based shape sensitivities has not yet been investigated. This thesis presents a first-of-its kind study on the numerical behavior of shape sensitivities using the XFEM. ii) The matter of overestimation of stresses using the XFEM, a longstanding issue with no concrete resolution available in the literature, is addressed for robust stress-based optimization. iii) LSM-based topology optimization is known to suffer from slow design evolution resulting from localized sensitivities. A recently proposed concept of geometric primitives as design variables alleviates this issue. Literature on this concept has been restricted to single material problems using linear elasticity. Using the XFEM, this thesis extends the concept of geometric primitives as design variables to multiphase multiphysics problems in 3D.
Advisors/Committee Members: Kurt K. Mautre, John A. Evans, Alireza Doostan, Carlos A. Felippa, Franck Vernerey.
Subjects/Keywords: computational mechanics; level set method; shape sensitivities; stress stabilization; topology optimization; XFEM; computational physics; Applied Mathematics; Engineering; Other Physics
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APA (6th Edition):
Sharma, A. (2017). Advances in Design and Optimization Using Immersed Boundary Methods. (Doctoral Dissertation). University of Colorado. Retrieved from https://scholar.colorado.edu/asen_gradetds/190
Chicago Manual of Style (16th Edition):
Sharma, Ashesh. “Advances in Design and Optimization Using Immersed Boundary Methods.” 2017. Doctoral Dissertation, University of Colorado. Accessed November 22, 2019.
https://scholar.colorado.edu/asen_gradetds/190.
MLA Handbook (7th Edition):
Sharma, Ashesh. “Advances in Design and Optimization Using Immersed Boundary Methods.” 2017. Web. 22 Nov 2019.
Vancouver:
Sharma A. Advances in Design and Optimization Using Immersed Boundary Methods. [Internet] [Doctoral dissertation]. University of Colorado; 2017. [cited 2019 Nov 22].
Available from: https://scholar.colorado.edu/asen_gradetds/190.
Council of Science Editors:
Sharma A. Advances in Design and Optimization Using Immersed Boundary Methods. [Doctoral Dissertation]. University of Colorado; 2017. Available from: https://scholar.colorado.edu/asen_gradetds/190
University of Colorado
27.
Jing, Yuxiang.
Deterioration of Multi-Functional Cementitious Materials in Nuclear Power Plants.
Degree: PhD, 2018, University of Colorado
URL: https://scholar.colorado.edu/cven_gradetds/360
► To ensure safe operation of nuclear power plants (NPPs) during their service life and enhance the performance of spent nuclear fuel (SNF) storage systems, comprehensive…
(more)
▼ To ensure safe operation of nuclear power plants (NPPs) during their service life and enhance the performance of spent nuclear fuel (SNF) storage systems, comprehensive investigation on the behavior of concrete and their components under the long-term nuclear radiation is needed. A theoretical model was developed first to predict the deterioration of concrete under neutron radiation, taking into account both of the effects of neutron radiation and the radiation-induced heating on the mechanical property and volume change of concrete. It was shown that the volume change of concrete is dominated by the expanding characteristic of aggregates. Since neutron radiation can deteriorate mechanical properties of the concrete materials, it’s critical to obtain the accurate neutron radiation levels in concrete structures during their service live. Neutron diffusion equations and heat conduction equation were used for prediction of neutron radiation and thermal field in concrete, respectively. The effects of potential variations of transport properties due to neutron radiation and elevated temperature on neutron diffusion in concrete were estimated. A simplified example of a typical concrete biological shielding wall was analyzed up to 80 years, and the results were discussed. The results show that neutron radiation and elevated temperature can result in considerable increases of neutron flux and fluence in the concrete. In order to understand the current state of knowledge about nuclear irradiated concrete, a collection of articles on neutron and gamma-ray radiation damage to concrete and/or its components was acquired. Information on testing conditions and concrete performance was extracted from the collected literature, and a database was developed. Data analysis of the effect of neutrons levels, water-cement ratio, aggregate fraction, and temperature on various properties of cementitious materials subjected to neutrons irradiation was conducted, and the results were presented. In order to monitor the long-term deterioration process of concrete used in NPPs, the self-sensing capability of carbon fiber reinforced cementitious composites under mechanical loading and elevated temperature was experimentally studied, and the results were described. It has potential to become a sensor and can be used to monitor the long-term variation of strain in concrete of NPPs structures or SNF storage systems.
Advisors/Committee Members: Yunping Xi, Franck Vernerey, Jeong-Hoon Song, Mija H. Hubler, Ross B. Corotis.
Subjects/Keywords: spent nuclear fuel; neutron radiation; concrete; nuclear power plants; deterioration; Civil Engineering; Nuclear
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APA (6th Edition):
Jing, Y. (2018). Deterioration of Multi-Functional Cementitious Materials in Nuclear Power Plants. (Doctoral Dissertation). University of Colorado. Retrieved from https://scholar.colorado.edu/cven_gradetds/360
Chicago Manual of Style (16th Edition):
Jing, Yuxiang. “Deterioration of Multi-Functional Cementitious Materials in Nuclear Power Plants.” 2018. Doctoral Dissertation, University of Colorado. Accessed November 22, 2019.
https://scholar.colorado.edu/cven_gradetds/360.
MLA Handbook (7th Edition):
Jing, Yuxiang. “Deterioration of Multi-Functional Cementitious Materials in Nuclear Power Plants.” 2018. Web. 22 Nov 2019.
Vancouver:
Jing Y. Deterioration of Multi-Functional Cementitious Materials in Nuclear Power Plants. [Internet] [Doctoral dissertation]. University of Colorado; 2018. [cited 2019 Nov 22].
Available from: https://scholar.colorado.edu/cven_gradetds/360.
Council of Science Editors:
Jing Y. Deterioration of Multi-Functional Cementitious Materials in Nuclear Power Plants. [Doctoral Dissertation]. University of Colorado; 2018. Available from: https://scholar.colorado.edu/cven_gradetds/360
University of Colorado
28.
Isbuga, Volkan.
Finite Strain Micromorphic Finite Element Analysis of Elastoplastic Geomaterials.
Degree: PhD, 2012, University of Colorado
URL: https://scholar.colorado.edu/cven_gradetds/290
► A three dimensional micromorphic finite strain linear isotropic elastoplastic model for geomaterials is developed and implemented into a finite element code. First, we present…
(more)
▼ A three dimensional micromorphic finite strain linear isotropic elastoplastic model for geomaterials is developed and implemented into a finite element code. First, we present the finite element formulation and implementation for the finite strain elasticity together with various examples to investigate the effects of the additional degrees of freedom, additional elastic moduli, length scale, and boundary conditions on micro-displacement tensor field that are all introduced by the micromorphic continuum. We present some findings and results of the finite element analysis of one dimensional and three dimensional problems. Three dimensional results demonstrate that the micromorphic contribution leads to unpredicted behavior under three dimensional stress states, whereas a one dimensional example presents comparatively clear trends for different cases. Examples also present length scale effects and computational benefits of the formulation by direct finite strain elasticity by providing a comparison with rate form of semi implicit time integration formulation in the Total Lagrangian finite element implementation. The work, then, is extended to finite strain micromorphic elastoplasticity by using slightly different types of yield criteria. We assume yield functions to be in the form of standard Drucker-Prager yield condition and a similar form of a Drucker-Prager-like yield function. The effect of elastic length scale is investigated in a one dimensional problem, together with the different yield functions and micro boundary conditions. We also consider a plain strain problem as more advanced geometry compared to the one dimensional example. The results which are obtained by Drucker-Prager-like yield criterion including micromorphic terms for this plain strain problem are presented to compare the effect of different number of additional degrees of freedom and the effect of the boundary conditions on the micro-displacement tensor field as well.
Advisors/Committee Members: Richard A. Regueiro, Franck Vernerey, Carlos A. Felippa, Ronald Y.S. Pak, Stein Sture.
Subjects/Keywords: elastoplasticity; finite element; finite strain; micromorphic; Civil Engineering
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APA (6th Edition):
Isbuga, V. (2012). Finite Strain Micromorphic Finite Element Analysis of Elastoplastic Geomaterials. (Doctoral Dissertation). University of Colorado. Retrieved from https://scholar.colorado.edu/cven_gradetds/290
Chicago Manual of Style (16th Edition):
Isbuga, Volkan. “Finite Strain Micromorphic Finite Element Analysis of Elastoplastic Geomaterials.” 2012. Doctoral Dissertation, University of Colorado. Accessed November 22, 2019.
https://scholar.colorado.edu/cven_gradetds/290.
MLA Handbook (7th Edition):
Isbuga, Volkan. “Finite Strain Micromorphic Finite Element Analysis of Elastoplastic Geomaterials.” 2012. Web. 22 Nov 2019.
Vancouver:
Isbuga V. Finite Strain Micromorphic Finite Element Analysis of Elastoplastic Geomaterials. [Internet] [Doctoral dissertation]. University of Colorado; 2012. [cited 2019 Nov 22].
Available from: https://scholar.colorado.edu/cven_gradetds/290.
Council of Science Editors:
Isbuga V. Finite Strain Micromorphic Finite Element Analysis of Elastoplastic Geomaterials. [Doctoral Dissertation]. University of Colorado; 2012. Available from: https://scholar.colorado.edu/cven_gradetds/290
University of Colorado
29.
Shahabi, Farhad.
Finite Strain Micromorphic Elasticity, Elastoplasticity, and Dynamics for Multiscale Finite Element Analysis.
Degree: PhD, 2017, University of Colorado
URL: https://scholar.colorado.edu/cven_gradetds/404
► This study stands as an attempt to consider the micro-structure of materials in a continuum framework by the aid of micromorphic continuum theory in…
(more)
▼ This study stands as an attempt to consider the micro-structure of materials in a continuum framework by the aid of micromorphic continuum theory in the sense of Eringen. Since classical continuum mechanics do not account for the micro-structural characteristics of materials, they cannot be used to address the macroscopic mechanical response of all micro-structured materials. In the "representative volume element (RVE)" based methods, classical continuum mechanics may be applied to analyze mechanical deformation and stresses of materials at the relevant micro-structural length-scale (such as grains of a polycrystalline metal, or sand, or metal matrix composite, etc), but when applying standard homogenization methods, such lower length scale effects get smeared out at the continuum scale. The micromorphic continuum theory provides the ability to incorporate the micro-structural effects into the macroscopic mechanical behavior. Therefore, the micromorphic continuum is a tool for a higher resolution multi-scale material modeling through capturing the material's micro-structural physics via bridging to the direct numerical simulations (DNS) at the lower length scale. In the micromorphic continuum theory of Eringen, the fundamental assumption is that the material is made of "micro-elements" in such a way that the classical continuum mechanics balance equations and thermodynamics are valid within a micro-element. Note that micro-elements represent the material's micro-structure in a micromorphic continuum. The micro-element deformation with respect to the centroid of a macroscopic continuum point is governed by an independent micro-deformation tensor <b>χ</b> which adds 9 additional degrees of freedom to the continuum model. The micromorphic additional degrees of freedom represent micro-stretch, micro-shear, and micro-rotation of the micro-elements. The macroscopic deformation (macro-element deformation) in the micromorphic continuum is handled through the deformation gradient tensor <b><i>F</i></b>. If the hypothesis of micromorphic continuum works, in a multi-scale modeling framework, assuming proper constitutive models can be formulated, and material parameters calibrated, micromorphic continuum theory may fill the gap between the RVE-micro-structural-length-scale models and the macroscopic continuum scale. The advantage of using micromorphic continuum is that it provides a chance of linking the macroscopic model to the lower length scale simulations (DNS) and reducing the computational cost by switching from DNS to the macro-scale finite element analysis or other numerical methods at the continuum scale. The linking is done through defining the overlap coupling region between the lower length scale analysis and micromorphic continuum to calibrate the material parameters and the micromorphic continuum model degrees of freedom. Therefore, in the framework of multi-scale modeling, micromorphic continuum can be used as a filter on top of the DNS simulations to capture underlying length scale and better inform the…
Advisors/Committee Members: Richard A. Regueiro, Ronald Y. S. Pak, John A. Evans, Franck Vernerey, Jeong-Hoon Song.
Subjects/Keywords: dynamics; elastoplasticity; finite element analysis; large deformation; micromorphic continuum; micropolar continuum; Applied Mechanics; Mechanical Engineering
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APA ·
Chicago ·
MLA ·
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CSE |
Export
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Manager
APA (6th Edition):
Shahabi, F. (2017). Finite Strain Micromorphic Elasticity, Elastoplasticity, and Dynamics for Multiscale Finite Element Analysis. (Doctoral Dissertation). University of Colorado. Retrieved from https://scholar.colorado.edu/cven_gradetds/404
Chicago Manual of Style (16th Edition):
Shahabi, Farhad. “Finite Strain Micromorphic Elasticity, Elastoplasticity, and Dynamics for Multiscale Finite Element Analysis.” 2017. Doctoral Dissertation, University of Colorado. Accessed November 22, 2019.
https://scholar.colorado.edu/cven_gradetds/404.
MLA Handbook (7th Edition):
Shahabi, Farhad. “Finite Strain Micromorphic Elasticity, Elastoplasticity, and Dynamics for Multiscale Finite Element Analysis.” 2017. Web. 22 Nov 2019.
Vancouver:
Shahabi F. Finite Strain Micromorphic Elasticity, Elastoplasticity, and Dynamics for Multiscale Finite Element Analysis. [Internet] [Doctoral dissertation]. University of Colorado; 2017. [cited 2019 Nov 22].
Available from: https://scholar.colorado.edu/cven_gradetds/404.
Council of Science Editors:
Shahabi F. Finite Strain Micromorphic Elasticity, Elastoplasticity, and Dynamics for Multiscale Finite Element Analysis. [Doctoral Dissertation]. University of Colorado; 2017. Available from: https://scholar.colorado.edu/cven_gradetds/404
. 
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