subject:(Direct method)

Universiteit Utrecht

1. Stoter, Marten. The Direct Method in Foreign Language Teaching in the Netherlands.

Degree: 2007, Universiteit Utrecht

URL: http://dspace.library.uu.nl:8080/handle/1874/31758

► The Direct Method in foreign language teaching in the Netherlands (or 'Doeltaal = Voertaal' principle as it is usually referred to) is generally noted as… (more)

Subjects/Keywords: Letteren; Direct Method; Doeltaal Voertaal

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APA (6^th Edition):

Stoter, M. (2007). The Direct Method in Foreign Language Teaching in the Netherlands. (Masters Thesis). Universiteit Utrecht. Retrieved from http://dspace.library.uu.nl:8080/handle/1874/31758

Chicago Manual of Style (16^th Edition):

Stoter, Marten. “The Direct Method in Foreign Language Teaching in the Netherlands.” 2007. Masters Thesis, Universiteit Utrecht. Accessed January 26, 2021. http://dspace.library.uu.nl:8080/handle/1874/31758.

MLA Handbook (7^th Edition):

Stoter, Marten. “The Direct Method in Foreign Language Teaching in the Netherlands.” 2007. Web. 26 Jan 2021.

Vancouver:

Stoter M. The Direct Method in Foreign Language Teaching in the Netherlands. [Internet] [Masters thesis]. Universiteit Utrecht; 2007. [cited 2021 Jan 26]. Available from: http://dspace.library.uu.nl:8080/handle/1874/31758.

Council of Science Editors:

Stoter M. The Direct Method in Foreign Language Teaching in the Netherlands. [Masters Thesis]. Universiteit Utrecht; 2007. Available from: http://dspace.library.uu.nl:8080/handle/1874/31758

Queens University

2. Bespalko, Dustin John. Validation of the Lattice Boltzmann Method for Direct Numerical Simulation of Wall-Bounded Turbulent Flows .

Degree: Mechanical and Materials Engineering, 2011, Queens University

URL: http://hdl.handle.net/1974/6729

► In this work, the lattice Boltzmann method (LBM) was validated for direct numerical simulation (DNS) of wall-bounded turbulent flows. The LBM is a discrete-particle-based method… (more)

▼ In this work, the lattice Boltzmann method (LBM) was validated for direct numerical simulation (DNS) of wall-bounded turbulent flows. The LBM is a discrete-particle-based method that numerically solves the Boltzmann equation as opposed to conventional DNS methods that are based on the Navier-Stokes (NS) equations. The advantages of the LBM are its simple implementation, its ability to handle complex geometries, and its scalability on modern high-performance computers. An LBM code was developed and used to simulate fully-developed turbulent channel flow. In order to validate the results, the turbulence statistics were compared to those calculated from a conventional NS-based finite difference (FD) simulation. In the present study, special care was taken to make sure the computational domains for LBM and FD simulations were the same. Similar validation studies in the literature have used LBM simulations with smaller computational domains in order to reduce the computational cost. However, reducing the size of the computational domain affects the turbulence statistics and confounds the results of the validation. The turbulence statistics calculated from the LBM and FD simulations were found to agree qualitatively; however, there were several significant deviations, particularly in the variance profiles. The largest discrepancy was in the variance of the pressure fluctuations, which differed by approximately 7%. Given that both the LBM and FD simulations resolved the full range of turbulent scales and no models were used, this error was deemed to be significant. The cause of the discrepancy in the pressure variance was found to be the compressibility of the LBM. The LBM allows the density to vary, while the FD method does not since it solves the incompressible form of the NS equations. The effect of the compressibility could be reduced by lowering the Mach number, but this would come at the cost of significantly increasing the computational cost. Therefore, the conclusion of this work is that, while the LBM is capable of producing accurate solutions for incompressible turbulent flows, it is significantly more expensive than conventional methods for simple wall-bounded turbulent flows.

Subjects/Keywords: Lattice Boltzmann Method ; Direct Numerical Simulation ; Turbulence

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APA (6^th Edition):

Bespalko, D. J. (2011). Validation of the Lattice Boltzmann Method for Direct Numerical Simulation of Wall-Bounded Turbulent Flows . (Thesis). Queens University. Retrieved from http://hdl.handle.net/1974/6729

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

Chicago Manual of Style (16^th Edition):

Bespalko, Dustin John. “Validation of the Lattice Boltzmann Method for Direct Numerical Simulation of Wall-Bounded Turbulent Flows .” 2011. Thesis, Queens University. Accessed January 26, 2021. http://hdl.handle.net/1974/6729.

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

MLA Handbook (7^th Edition):

Bespalko, Dustin John. “Validation of the Lattice Boltzmann Method for Direct Numerical Simulation of Wall-Bounded Turbulent Flows .” 2011. Web. 26 Jan 2021.

Vancouver:

Bespalko DJ. Validation of the Lattice Boltzmann Method for Direct Numerical Simulation of Wall-Bounded Turbulent Flows . [Internet] [Thesis]. Queens University; 2011. [cited 2021 Jan 26]. Available from: http://hdl.handle.net/1974/6729.

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

Council of Science Editors:

Bespalko DJ. Validation of the Lattice Boltzmann Method for Direct Numerical Simulation of Wall-Bounded Turbulent Flows . [Thesis]. Queens University; 2011. Available from: http://hdl.handle.net/1974/6729

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

Texas A&M University

3. Kang, Shin Kyu. Immersed Boundary Methods in the Lattice Boltzmann Equation for Flow Simulation.

Degree: PhD, Nuclear Engineering, 2012, Texas A&M University

URL: http://hdl.handle.net/1969.1/ETD-TAMU-2010-12-8710

► In this dissertation, we explore direct-forcing immersed boundary methods (IBM) under the framework of the lattice Boltzmann method (LBM), which is called the direct-forcing immersed… (more)

▼ In this dissertation, we explore direct-forcing immersed boundary methods (IBM) under the framework of the lattice Boltzmann method (LBM), which is called the direct-forcing immersed boundary-lattice Boltzmann method (IB-LBM). First, we derive the direct-forcing formula based on the split-forcing lattice Boltzmann equation, which recovers the Navier-Stokes equation with second-order accuracy and enables us to develop a simple and accurate formula due to its kinetic nature. Then, we assess the various interface schemes under the derived direct-forcing formula. We consider not only diffuse interface schemes but also a sharp interface scheme. All tested schemes show a second-order overall accuracy. In the simulation of stationary complex boundary flows, we can observe that the sharper the interface scheme is, the more accurate the results are. The interface schemes are also applied to moving boundary problems. The sharp interface scheme shows better accuracy than the diffuse interface schemes but generates spurious oscillation in the boundary forcing terms due to the discontinuous change of nodes for the interpolation. In contrast, the diffuse interface schemes show smooth change in the boundary forcing terms but less accurate results because of discrete delta functions. Hence, the diffuse interface scheme with a corrected radius can be adopted to obtain both accurate and smooth results. Finally, a direct-forcing immersed boundary method (IBM) for the thermal lattice Boltzmann method (TLBM) is proposed to simulate non-isothermal flows. The direct-forcing IBM formulas for thermal equations are derived based on two TLBM models: a double-population model with a simplified thermal lattice Boltzmann equation (Model 1) and a hybrid model with an advection-diffusion equation of temperature (Model 2). The proposed methods are validated through natural convection problems with stationary and moving boundaries. In terms of accuracy, the results obtained from the IBMs based on both models are comparable and show a good agreement with those from other numerical methods. In contrast, the IBM based on Model 2 is more numerically efficient than the IBM based on Model 1. Overall, this study serves to establish the feasibility of the direct-forcing IB-LBM as a viable tool for computing various complex and/or moving boundary flow problems. Advisors/Committee Members: Hassan, Yassin A. (advisor), Annamalai, Kalyan (committee member), Chen, Hamn-Ching (committee member), Marlow, William H. (committee member).

Subjects/Keywords: Direct-forcing immersed boundary method; Lattice Boltzmann Method; Complex moving boundary

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APA (6^th Edition):

Kang, S. K. (2012). Immersed Boundary Methods in the Lattice Boltzmann Equation for Flow Simulation. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/ETD-TAMU-2010-12-8710

Chicago Manual of Style (16^th Edition):

Kang, Shin Kyu. “Immersed Boundary Methods in the Lattice Boltzmann Equation for Flow Simulation.” 2012. Doctoral Dissertation, Texas A&M University. Accessed January 26, 2021. http://hdl.handle.net/1969.1/ETD-TAMU-2010-12-8710.

MLA Handbook (7^th Edition):

Kang, Shin Kyu. “Immersed Boundary Methods in the Lattice Boltzmann Equation for Flow Simulation.” 2012. Web. 26 Jan 2021.

Vancouver:

Kang SK. Immersed Boundary Methods in the Lattice Boltzmann Equation for Flow Simulation. [Internet] [Doctoral dissertation]. Texas A&M University; 2012. [cited 2021 Jan 26]. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2010-12-8710.

Council of Science Editors:

Kang SK. Immersed Boundary Methods in the Lattice Boltzmann Equation for Flow Simulation. [Doctoral Dissertation]. Texas A&M University; 2012. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2010-12-8710

Virginia Tech

4. Grey, Christopher Norton. Cold-Formed Steel Behavior: Elastic Buckling Simplified Methods for Structural Members with Edge-Stiffened Holes and Purlin Distortional Buckling Strength Under Gravity Loading.

Degree: MS, Structural Engineering and Materials, 2011, Virginia Tech

URL: http://hdl.handle.net/10919/32829

► Elastic Buckling Simplified Methods for Structural Members with Edge-Stiffened Holes: Presently, the current design methods available to engineers to predict the strength of cold-formed steel… (more)

▼ Elastic Buckling Simplified Methods for Structural Members with Edge-Stiffened Holes: Presently, the current design methods available to engineers to predict the strength of cold-formed steel members with edge-stiffened holes remains largely unaddressed in the North American Specification for the Design of Cold-Formed Steel Structural Members (NAS). Research was conducted to explore and develop a further understanding of the effects of stiffened edge holes on the elastic buckling parameters for local, distortional, and global buckling. Elastic buckling parameter studies have been conducted on a suite of cold-formed members including recently developed DeltaSTUDs manufactured by Steelform Building Products, Inc. and a series of common Steel Stud Manufacturers Association (SSMA) members. Furthermore, a suite of simplified methods for determining elastic buckling parameters used to predict capacity with the Direct Strength Method (DSM) for members with edge stiffened holes were developed and validated. The elastic buckling studies are used to validate the simplified methods presented in this thesis. All simplified methods are further validated with thin shell finite element eigen-buckling parameter studies where the edge-stiffened holes are explicitly modeled. Purlin Distortional Buckling Strength Under Gravity Loading: Laterally braced cold-formed steel beams generally fail due to local and/or distortional buckling in combination with yielding. For many members, distortional buckling is the dominant buckling mode and is addressed in the current North American Specification for the Design of Cold-formed Steel Structural Members. The current main code equation, AISI C3.1.4-10 for calculating the available distortional buckling stress was derived experimentally based on a series of four-point bending tests at John Hopkins University. Where this provides a good basis for determining capacity, in most loading conditions purlins are subjected to a downward uniform loading that provides additional resistance to distortional buckling in the top flange beyond the resistance of the steel roofing panel. This research describes an experimental study to explore and quantify the difference in distortional buckling flexural capacity of metal building Z-purlins treated as isolated components and Z-purlins loaded with a constant pressure applied to metal roof panels. A series of three different types of tests have been developed to quantify the system effect provided by the metal roof panels as well as downward pressure on distortional buckling. Results are also extended to validate the Direct Strength Method when predicting flexural capacity of purlins in a roof system. Advisors/Committee Members: Moen, Cristopher D. (committeechair), Eatherton, Matthew R. (committee member), Wright, William J. (committee member).

Subjects/Keywords: finite strip method; direct strength method; computational modeling; finite element solution

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APA (6^th Edition):

Grey, C. N. (2011). Cold-Formed Steel Behavior: Elastic Buckling Simplified Methods for Structural Members with Edge-Stiffened Holes and Purlin Distortional Buckling Strength Under Gravity Loading. (Masters Thesis). Virginia Tech. Retrieved from http://hdl.handle.net/10919/32829

Chicago Manual of Style (16^th Edition):

Grey, Christopher Norton. “Cold-Formed Steel Behavior: Elastic Buckling Simplified Methods for Structural Members with Edge-Stiffened Holes and Purlin Distortional Buckling Strength Under Gravity Loading.” 2011. Masters Thesis, Virginia Tech. Accessed January 26, 2021. http://hdl.handle.net/10919/32829.

MLA Handbook (7^th Edition):

Grey, Christopher Norton. “Cold-Formed Steel Behavior: Elastic Buckling Simplified Methods for Structural Members with Edge-Stiffened Holes and Purlin Distortional Buckling Strength Under Gravity Loading.” 2011. Web. 26 Jan 2021.

Vancouver:

Grey CN. Cold-Formed Steel Behavior: Elastic Buckling Simplified Methods for Structural Members with Edge-Stiffened Holes and Purlin Distortional Buckling Strength Under Gravity Loading. [Internet] [Masters thesis]. Virginia Tech; 2011. [cited 2021 Jan 26]. Available from: http://hdl.handle.net/10919/32829.

Council of Science Editors:

Grey CN. Cold-Formed Steel Behavior: Elastic Buckling Simplified Methods for Structural Members with Edge-Stiffened Holes and Purlin Distortional Buckling Strength Under Gravity Loading. [Masters Thesis]. Virginia Tech; 2011. Available from: http://hdl.handle.net/10919/32829

University of Hawaii – Manoa

5. Zhao, Lijuan. Economic determinants and consequences of direct method cash flow disclosure.

Degree: 2016, University of Hawaii – Manoa

URL: http://hdl.handle.net/10125/101381

►

Ph.D. University of Hawaii at Manoa 2012.

The statement of cash flows of a business can be presented by using either the direct method (DM)… (more)

Subjects/Keywords: cash flow; direct method; indirect method; international management

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APA (6^th Edition):

Zhao, L. (2016). Economic determinants and consequences of direct method cash flow disclosure. (Thesis). University of Hawaii – Manoa. Retrieved from http://hdl.handle.net/10125/101381

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

Chicago Manual of Style (16^th Edition):

Zhao, Lijuan. “Economic determinants and consequences of direct method cash flow disclosure.” 2016. Thesis, University of Hawaii – Manoa. Accessed January 26, 2021. http://hdl.handle.net/10125/101381.

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

MLA Handbook (7^th Edition):

Zhao, Lijuan. “Economic determinants and consequences of direct method cash flow disclosure.” 2016. Web. 26 Jan 2021.

Vancouver:

Zhao L. Economic determinants and consequences of direct method cash flow disclosure. [Internet] [Thesis]. University of Hawaii – Manoa; 2016. [cited 2021 Jan 26]. Available from: http://hdl.handle.net/10125/101381.

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

Council of Science Editors:

Zhao L. Economic determinants and consequences of direct method cash flow disclosure. [Thesis]. University of Hawaii – Manoa; 2016. Available from: http://hdl.handle.net/10125/101381

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

University of Cincinnati

6. Yang, Xiaolin. Direct and Line Based Iterative Methods for Solving Sparse Block Linear Systems.

Degree: MS, Engineering and Applied Science: Aerospace Engineering, 2018, University of Cincinnati

URL: http://rave.ohiolink.edu/etdc/view?acc_num=ucin1543921330763997

► Solving sparse linear system of equations represents the major computation cost in many scientific and engineering areas. There are two major approaches for solving large… (more)

Subjects/Keywords: Engineering; sparse matrix; direct method; line-based iterative method; Discontinuous Galerkin Method

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APA (6^th Edition):

Yang, X. (2018). Direct and Line Based Iterative Methods for Solving Sparse Block Linear Systems. (Masters Thesis). University of Cincinnati. Retrieved from http://rave.ohiolink.edu/etdc/view?acc_num=ucin1543921330763997

Chicago Manual of Style (16^th Edition):

Yang, Xiaolin. “Direct and Line Based Iterative Methods for Solving Sparse Block Linear Systems.” 2018. Masters Thesis, University of Cincinnati. Accessed January 26, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1543921330763997.

MLA Handbook (7^th Edition):

Yang, Xiaolin. “Direct and Line Based Iterative Methods for Solving Sparse Block Linear Systems.” 2018. Web. 26 Jan 2021.

Vancouver:

Yang X. Direct and Line Based Iterative Methods for Solving Sparse Block Linear Systems. [Internet] [Masters thesis]. University of Cincinnati; 2018. [cited 2021 Jan 26]. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=ucin1543921330763997.

Council of Science Editors:

Yang X. Direct and Line Based Iterative Methods for Solving Sparse Block Linear Systems. [Masters Thesis]. University of Cincinnati; 2018. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=ucin1543921330763997

Queens University

7. Jabbari Sahebari, Aidin. Analysis of Idealized Numerical Simulations to Calibrate and Validate Boundary Layer Models .

Degree: Civil Engineering, 2015, Queens University

URL: http://hdl.handle.net/1974/13568

► The accuracy of the inertial dissipation method (IDM), commonly applied to estimate the observed rate of turbulent dissipation in bottom boundary layers (BBL), is evaluated… (more)

▼ The accuracy of the inertial dissipation method (IDM), commonly applied to estimate the observed rate of turbulent dissipation in bottom boundary layers (BBL), is evaluated by performing direct numerical simulations (DNS) and large eddy simulations (LES) of unidirectional turbulent channel flows. Errors in the IDM occur as the mean velocity is commonly used for the convection velocity and when the canonical Kolmogorov -5/3 constants, which assume isotropy and homogeneity of the flow, are applied. The optimal convection velocity, as previously shown by many researchers, is found to be 2 times greater than the local mean velocity near the bed and the Kolmogorov constants are significantly affected by anisotropy. Usage of the canonical Kolmogorov constants leads to significant errors (>50%) in computation of dissipation. Using the same DNS and LES data, the accuracy of Kolmogorov 2/3 constants, used in the structure function method (SFM) to compute dissipation, is also investigated. As with the IDM, comparison of the dissipation, calculated directly from DNS/LES with that from the SFM, shows that usage of canonical constants results in considerable error (>50%) from the vertical or spanwise velocity components. Application of anisotropy-adjusted constants to data from the BBL of Lake Erie shows that these constants improve computed dissipation by a factor of two, with results within 20% of published dissipation obtained from the Batchelor fitting method. DNS and LES of oscillating turbulent flows were also carried out to calibrate and evaluate common analytical models used in oscillatory BBLs in lakes and costal oceans. These include the log-law, Stokes second problem, the IDM, and a one-equation Spalart-Allmaras model. Velocity profile predictions from the Spalart-Allmaras model were found to be more accurate than those from the log-law and Stokes’ second problem. Comparison of the LES data and the turbulence models, with published field measurements, shows that the rate of dissipation from the IDM is more accurate than that obtained from the log-law, particularly when the flow reverses. The differences between the IDM and LES suggest that the errors in prediction of dissipation can be due to the anisotropy conditions in the BBL.

Subjects/Keywords: Structure Function Method ; Direct Numerical Simulations ; Inertial Dissipation Method ; Large Eddy Simulations ; Boundary Layers

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APA (6^th Edition):

Jabbari Sahebari, A. (2015). Analysis of Idealized Numerical Simulations to Calibrate and Validate Boundary Layer Models . (Thesis). Queens University. Retrieved from http://hdl.handle.net/1974/13568

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

Chicago Manual of Style (16^th Edition):

Jabbari Sahebari, Aidin. “Analysis of Idealized Numerical Simulations to Calibrate and Validate Boundary Layer Models .” 2015. Thesis, Queens University. Accessed January 26, 2021. http://hdl.handle.net/1974/13568.

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

MLA Handbook (7^th Edition):

Jabbari Sahebari, Aidin. “Analysis of Idealized Numerical Simulations to Calibrate and Validate Boundary Layer Models .” 2015. Web. 26 Jan 2021.

Vancouver:

Jabbari Sahebari A. Analysis of Idealized Numerical Simulations to Calibrate and Validate Boundary Layer Models . [Internet] [Thesis]. Queens University; 2015. [cited 2021 Jan 26]. Available from: http://hdl.handle.net/1974/13568.

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

Council of Science Editors:

Jabbari Sahebari A. Analysis of Idealized Numerical Simulations to Calibrate and Validate Boundary Layer Models . [Thesis]. Queens University; 2015. Available from: http://hdl.handle.net/1974/13568

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

Delft University of Technology

8. Swart, Wouter (author). Methods for improving the computational performance of sequentially linear analsysis.

Degree: 2018, Delft University of Technology

URL: http://resolver.tudelft.nl/uuid:dc35a7e3-beb7-4d46-88c6-36e6f980a597

►

The numerical simulation of brittle failure with nonlinear finite element analysis (NLFEA) remains a challenge due to robustness issues. These problems are attributed to the… (more)

▼

The numerical simulation of brittle failure with nonlinear finite element analysis (NLFEA) remains a challenge due to robustness issues. These problems are attributed to the softening material behaviour and the iterative nature of the Newton-Raphson type methods used in NLFEA. However, robust numerical simulations become increasingly important, for example due to recent developments in Groningen. To address these issues, sequentially linear analysis (SLA) was developed which exploits the fact that a linear analysis is inherently stable. By assuming a stepwise material degradation the nonlinear response of a structure can be approximated with a sequence of linear analyses. Although this approach has been proven to be effective for several case studies, the numerical performance is still a problem that has to be solved. After every linear analysis, a single element is damaged resulting in incremental damage. As a result, the system of equations only changes locally between these linear analyses. Traditional solution techniques do not exploit this property and calculate a matrix factorisation every linear analysis, resulting in high computational times per analysis step. Since SLA typically requires many linear analyses to obtain the desired structural response, this leads to unacceptable analysis times. The aim of this thesis is to improve the computational performance of SLA by developing numerical solution techniques which exploit the incremental approach of SLA. To this extend, the following methods have been developed. A direct solution technique has been developed which is based on the Woodbury matrix identity. This identity allows for the numerically cheap computation of the inverse of a low-rank corrected matrix. In this approach, the expensive matrix factorisation does not have to be calculated every linear analysis step. Instead, the old factorisation can be reused along with some additional matrix- and vector multiplications and solving a significantly smaller linear system of equations. An optimal strategy is derived to determine at which point a new factorisation should be calculated. An improved preconditioner for the conjugate gradient (CG) method has been developed. Instead of an incomplete factorisation, the complete factorisation is used as a preconditioner which reduces the number of required CG iterations significantly. The point at which too many CG iterations are required and a new factorisation is necessary, is determined using the same strategy as the first method. From numerical experiments it follows that both methods perform significantly better than the direct solution method, especially for large 3-dimensional problems. The best performance is achieved using the Woodbury matrix identity resulting in the solver no longer being the dominant factor in SLA. Furthermore, significantly larger problems are not solvable in time frames in which previously only smaller problems were solved.

Applied Mathematics

Advisors/Committee Members: van Gijzen, Martin (mentor), Schreppers, G.M.A (graduation committee), Rots, Jan (graduation committee), van Horssen, Wim (graduation committee), Delft University of Technology (degree granting institution).

Subjects/Keywords: Finite Element Analysis; Preconditioning; Structural analysis; Direct method; Iterative method; Low-rank matrix correction

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APA (6^th Edition):

Swart, W. (. (2018). Methods for improving the computational performance of sequentially linear analsysis. (Masters Thesis). Delft University of Technology. Retrieved from http://resolver.tudelft.nl/uuid:dc35a7e3-beb7-4d46-88c6-36e6f980a597

Chicago Manual of Style (16^th Edition):

Swart, Wouter (author). “Methods for improving the computational performance of sequentially linear analsysis.” 2018. Masters Thesis, Delft University of Technology. Accessed January 26, 2021. http://resolver.tudelft.nl/uuid:dc35a7e3-beb7-4d46-88c6-36e6f980a597.

MLA Handbook (7^th Edition):

Swart, Wouter (author). “Methods for improving the computational performance of sequentially linear analsysis.” 2018. Web. 26 Jan 2021.

Vancouver:

Swart W(. Methods for improving the computational performance of sequentially linear analsysis. [Internet] [Masters thesis]. Delft University of Technology; 2018. [cited 2021 Jan 26]. Available from: http://resolver.tudelft.nl/uuid:dc35a7e3-beb7-4d46-88c6-36e6f980a597.

Council of Science Editors:

Swart W(. Methods for improving the computational performance of sequentially linear analsysis. [Masters Thesis]. Delft University of Technology; 2018. Available from: http://resolver.tudelft.nl/uuid:dc35a7e3-beb7-4d46-88c6-36e6f980a597

University of Illinois – Urbana-Champaign

9. Uddin, Hasib. Direct numerical simulation of a tumbling short cylinder in low Reynolds number compressible flow.

Degree: PhD, 0242, 2014, University of Illinois – Urbana-Champaign

URL: http://hdl.handle.net/2142/50381

► The delivery of fusion material to the center of a laser inertial confinement engine happens by injecting a frozen hydrogen isotope mixture that resides inside… (more)

▼ The delivery of fusion material to the center of a laser inertial confinement engine happens by injecting a frozen hydrogen isotope mixture that resides inside a carefully crafted capsule called hohlraum. Because of the injection mechanism, the capsule necessarily has the shape of a modified short cylinder traveling along its axis of symmetry. The flow details and stability of this geometry are of significant importance to the reliable operation of the device. The gas inside the fusion chamber is very hot and the viscosity is relatively high, which for the typical injection velocities of the capsule results in a low Reynolds number flow. In this connection, a low Reynolds number compressible flow past a dynamically moving rigid short cylinder has been investigated using three-dimensional direct numerical simulation (DNS) as a model of the real capsule. A Cartesian-based novel embedded geometry method for compressible fluid-structure interaction problems is developed and coupled with a low-numerical-dissipation compressible flow solver to perform simulations in a parallel multiprocessor environment. In this method, the surface of the cylinder is uniquely identified by a zero level set separating the fluid and solid region. A PDE-based global extension technique inspired by analytical continuation is used to smoothly propagate the surface boundary conditions inside the fictitious solid domain. This approach ensures smooth and noise-free reconstruction of pressure and viscous stresses on the surface of the solid body and utilization of a global high-order spatial discretization scheme due to the smooth nature of the flow quantities at each time step stage. The translational and rotational dynamics of the cylinder by modeling the 6-degree of freedom (DoF) motion employ a non-singular quaternion-based framework. The longitudinal stability of the cylinder is affected by the variation in angle of attack, aspect ratio and Reynolds number. The present work focuses on Reynolds number, Re = 60 and a Mach number, M = 0.25 to closely mimic the flow conditions inside an inertial confinement fusion chamber. A critical angle of attack has been identified beyond which the short cylinder will start to tumble based on a set of stationary simulations. Additionally, the force coefficients and pitching moments from coupled moving boundary simulations are investigated. Advisors/Committee Members: Pantano-Rubino, Carlos A. (advisor), Pantano-Rubino, Carlos A. (Committee Chair), Christensen, Kenneth T. (committee member), Vakakis, Alexander F. (committee member), Bodony, Daniel J. (committee member).

Subjects/Keywords: Embedded geometry method; immersed boundary method; fluid-structure interaction; direct numerical simulation; tumbling cylinder

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APA (6^th Edition):

Uddin, H. (2014). Direct numerical simulation of a tumbling short cylinder in low Reynolds number compressible flow. (Doctoral Dissertation). University of Illinois – Urbana-Champaign. Retrieved from http://hdl.handle.net/2142/50381

Chicago Manual of Style (16^th Edition):

Uddin, Hasib. “Direct numerical simulation of a tumbling short cylinder in low Reynolds number compressible flow.” 2014. Doctoral Dissertation, University of Illinois – Urbana-Champaign. Accessed January 26, 2021. http://hdl.handle.net/2142/50381.

MLA Handbook (7^th Edition):

Uddin, Hasib. “Direct numerical simulation of a tumbling short cylinder in low Reynolds number compressible flow.” 2014. Web. 26 Jan 2021.

Vancouver:

Uddin H. Direct numerical simulation of a tumbling short cylinder in low Reynolds number compressible flow. [Internet] [Doctoral dissertation]. University of Illinois – Urbana-Champaign; 2014. [cited 2021 Jan 26]. Available from: http://hdl.handle.net/2142/50381.

Council of Science Editors:

Uddin H. Direct numerical simulation of a tumbling short cylinder in low Reynolds number compressible flow. [Doctoral Dissertation]. University of Illinois – Urbana-Champaign; 2014. Available from: http://hdl.handle.net/2142/50381

Oklahoma State University

10. Zhang, Haoyu. Rapid Determination of Dissolved Organic Carbon by Persulfate Oxidation Vial and Uv/vis Spectrophotometer.

Degree: Civil & Environmental Engineering, 2013, Oklahoma State University

URL: http://hdl.handle.net/11244/15214

► Dissolved organic carbon (DOC) has long been studied to determine and characterize natural organic matter (NOM). The goal of this thesis is to test a… (more)

Subjects/Keywords: dissolved organic carbon; method performance; persulfate oxidation; toc direct method; uv/vis

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APA (6^th Edition):

Zhang, H. (2013). Rapid Determination of Dissolved Organic Carbon by Persulfate Oxidation Vial and Uv/vis Spectrophotometer. (Thesis). Oklahoma State University. Retrieved from http://hdl.handle.net/11244/15214

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

Chicago Manual of Style (16^th Edition):

Zhang, Haoyu. “Rapid Determination of Dissolved Organic Carbon by Persulfate Oxidation Vial and Uv/vis Spectrophotometer.” 2013. Thesis, Oklahoma State University. Accessed January 26, 2021. http://hdl.handle.net/11244/15214.

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

MLA Handbook (7^th Edition):

Zhang, Haoyu. “Rapid Determination of Dissolved Organic Carbon by Persulfate Oxidation Vial and Uv/vis Spectrophotometer.” 2013. Web. 26 Jan 2021.

Vancouver:

Zhang H. Rapid Determination of Dissolved Organic Carbon by Persulfate Oxidation Vial and Uv/vis Spectrophotometer. [Internet] [Thesis]. Oklahoma State University; 2013. [cited 2021 Jan 26]. Available from: http://hdl.handle.net/11244/15214.

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

Council of Science Editors:

Zhang H. Rapid Determination of Dissolved Organic Carbon by Persulfate Oxidation Vial and Uv/vis Spectrophotometer. [Thesis]. Oklahoma State University; 2013. Available from: http://hdl.handle.net/11244/15214

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

Cornell University

11. Sheheitli, Hiba. On The Dynamics Of Systems With Vastly Different Frequencies.

Degree: PhD, Theoretical and Applied Mechanics, 2012, Cornell University

URL: http://hdl.handle.net/1813/29321

► The method of direct partition of motion (DPM) has been widely used to study the dynamics of non-autonomous oscillatory systems subject to external high frequency… (more)

▼ The method of direct partition of motion (DPM) has been widely used to study the dynamics of non-autonomous oscillatory systems subject to external high frequency excitation. In this work, we explore the non-trivial dynamics that arise in autonomous systems with vastly different frequencies, in which the fast excitation is intrinsic to the system and possibly influenced by the slow dynamics. Using three model problems, we illustrate how DPM could be useful for the analysis of such systems and when combined with WKB can serve to capture the strong modulation of a fast oscillator due to coupling to a much slower one -a phenomenon that is not readily handled using standard perturbation methods. First, we study a system of three coupled limit cycle oscillators, which when uncoupled, have the frequencies [omega]1 = O (1), [omega]2 = O(1/[epsilon]) and [omega]3 = O(1/[epsilon]2), respectively, where [epsilon] << 1. Approximate expressions for the limit cycles of oscillators 1 and 2 are found in terms of Jacobi elliptic functions. For coupling strengths exceeding critical bifurcation values, the limit cycle of oscillator 1 or 2 is found to disappear. In the second problem, we consider a simple pendulum coupled to a horizontal mass-spring system of a much higher frequency. In contrast to the first problem, the coupling here allows the slow oscillator to affect the leading order dynamics of the fast oscillator. This calls for a rescaling of fast time, inspired by the WKB method, to be employed in conjunction with DPM. We obtain a critical energy value at which a pitchfork bifurcation of periodic orbits is found to occur, giving rise to non-local periodic and quasi-periodic orbits in which the pendulum oscillates about an angle between zero and [pi]/2 from the downwards position. Finally, the developed method is utilized to explain the non-trivial dynamics arising in a model of a thin elastica presented by Cusumano and Moon in 1995. We observe that for the corresponding experimental system, the ratio of the two natural frequencies of the system was [ALMOST EQUAL TO] 44 which can be considered to be of O (1/[epsilon]) where [epsilon] << 1. Hence, the system is best viewed as one with vastly different frequencies. The method leads to an approximate expression for the non-local modes of the type observed in the experiments as well as the bifurcation energy value at which these modes are born. The formal approximate solutions obtained for these problems are validated by comparison with numerical integration. Advisors/Committee Members: Rand, Richard Herbert (chair), Healey, Timothy James (committee member), Strogatz, Steven H (committee member).

Subjects/Keywords: method of direct partition of motion; non-local modes

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APA (6^th Edition):

Sheheitli, H. (2012). On The Dynamics Of Systems With Vastly Different Frequencies. (Doctoral Dissertation). Cornell University. Retrieved from http://hdl.handle.net/1813/29321

Chicago Manual of Style (16^th Edition):

Sheheitli, Hiba. “On The Dynamics Of Systems With Vastly Different Frequencies.” 2012. Doctoral Dissertation, Cornell University. Accessed January 26, 2021. http://hdl.handle.net/1813/29321.

MLA Handbook (7^th Edition):

Sheheitli, Hiba. “On The Dynamics Of Systems With Vastly Different Frequencies.” 2012. Web. 26 Jan 2021.

Vancouver:

Sheheitli H. On The Dynamics Of Systems With Vastly Different Frequencies. [Internet] [Doctoral dissertation]. Cornell University; 2012. [cited 2021 Jan 26]. Available from: http://hdl.handle.net/1813/29321.

Council of Science Editors:

Sheheitli H. On The Dynamics Of Systems With Vastly Different Frequencies. [Doctoral Dissertation]. Cornell University; 2012. Available from: http://hdl.handle.net/1813/29321

North Carolina State University

12. Klingshirn, Daniel J. Experimental and Analytical Investigation of Optimized Cold-Formed Steel Compression Members.

Degree: MS, Civil Engineering, 2009, North Carolina State University

URL: http://www.lib.ncsu.edu/resolver/1840.16/2119

► In recent years, load-bearing light steel framing (LSF) systems have become popular in the low to mid-rise construction market in the United States. This construction… (more)

▼ In recent years, load-bearing light steel framing (LSF) systems have become popular in the low to mid-rise construction market in the United States. This construction market covers a wide range of building usage, including apartment and office buildings, hotels, and schools. In the past, standard C-shaped metal studs have been the only option for designers and contractors when selecting a cross section for load bearing studs. An alternative cross section, which has primarily been used as a roof purlin in Europe and is seldom found in the U.S., is the sigma-shaped section. Recognizing the potential of this section for use within a LSF system, a research program was completed at North Carolina State UniversityÃ¢â‚¬â„¢s Constructed Facilities Laboratory (CFL) to evaluate the axial compression capacity for the proprietary stud product SigmaStudÃ‚Â®. The experimental test program, which includes fifty-eight sigma-shaped stud tests and forty-eight comparable C-stud tests, was developed with the ultimate goal of adding the SigmaStudÃ‚Â® to the pre-qualified column set of the relatively new Direct Strength Method (DSM) design method. Studs were tested at various lengths to force global, distortional, and local buckling failure modes. Additionally, the test program contained studs with and without web holes. Comparisons of experimental results with the AISI design methods, Effective Width (EWM) and Direct Strength (DSM), are discussed. Based on the results of this research program, the SigmaStudÃ‚Â® section is recommended to be added to the pre-qualified member set of the DSM. Both design methods are shown to produce accurate strength predictions. Another important conclusion from this test program is that the optimized sigma-shaped stud is shown to be a much more efficient use of material than a comparable C-stud. Strength increases ranged from 30-175% for 24Ã¢â‚¬Â studs and 45-450% for 120Ã¢â‚¬Â studs. Web holes were shown to decrease stud capacity in most cases, although strength increases were observed in both short and long studs. Additionally, long studs are shown to be very sensitive to loading eccentricity, while short studs are not. Advisors/Committee Members: Dr. Nabil A. Rahman, Committee Co-Chair (advisor), Dr. Emmett Sumner, Committee Chair (advisor), Dr. James Nau, Committee Member (advisor).

Subjects/Keywords: cold-formed steel; Direct Strength Method; optimized sections; sigma section

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APA (6^th Edition):

Klingshirn, D. J. (2009). Experimental and Analytical Investigation of Optimized Cold-Formed Steel Compression Members. (Thesis). North Carolina State University. Retrieved from http://www.lib.ncsu.edu/resolver/1840.16/2119

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

Chicago Manual of Style (16^th Edition):

Klingshirn, Daniel J. “Experimental and Analytical Investigation of Optimized Cold-Formed Steel Compression Members.” 2009. Thesis, North Carolina State University. Accessed January 26, 2021. http://www.lib.ncsu.edu/resolver/1840.16/2119.

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

MLA Handbook (7^th Edition):

Klingshirn, Daniel J. “Experimental and Analytical Investigation of Optimized Cold-Formed Steel Compression Members.” 2009. Web. 26 Jan 2021.

Vancouver:

Klingshirn DJ. Experimental and Analytical Investigation of Optimized Cold-Formed Steel Compression Members. [Internet] [Thesis]. North Carolina State University; 2009. [cited 2021 Jan 26]. Available from: http://www.lib.ncsu.edu/resolver/1840.16/2119.

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

Council of Science Editors:

Klingshirn DJ. Experimental and Analytical Investigation of Optimized Cold-Formed Steel Compression Members. [Thesis]. North Carolina State University; 2009. Available from: http://www.lib.ncsu.edu/resolver/1840.16/2119

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

University of the Western Cape

13. Streit, Günther Arthur. Comparison of the accuracy of direct versus indirect bracket placement in orthodontics: An in vitro study .

Degree: 2020, University of the Western Cape

URL: http://hdl.handle.net/11394/7304

► The purpose of this study was to compare the accuracy of direct versus indirect bracket placement in orthodontics in a controlled setting. The more accurate… (more)

Subjects/Keywords: Treatment time; Patient care; Orthodontics; Direct and indirect method; Bracket placement

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APA (6^th Edition):

Streit, G. A. (2020). Comparison of the accuracy of direct versus indirect bracket placement in orthodontics: An in vitro study . (Thesis). University of the Western Cape. Retrieved from http://hdl.handle.net/11394/7304

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

Chicago Manual of Style (16^th Edition):

Streit, Günther Arthur. “Comparison of the accuracy of direct versus indirect bracket placement in orthodontics: An in vitro study .” 2020. Thesis, University of the Western Cape. Accessed January 26, 2021. http://hdl.handle.net/11394/7304.

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

MLA Handbook (7^th Edition):

Streit, Günther Arthur. “Comparison of the accuracy of direct versus indirect bracket placement in orthodontics: An in vitro study .” 2020. Web. 26 Jan 2021.

Vancouver:

Streit GA. Comparison of the accuracy of direct versus indirect bracket placement in orthodontics: An in vitro study . [Internet] [Thesis]. University of the Western Cape; 2020. [cited 2021 Jan 26]. Available from: http://hdl.handle.net/11394/7304.

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

Council of Science Editors:

Streit GA. Comparison of the accuracy of direct versus indirect bracket placement in orthodontics: An in vitro study . [Thesis]. University of the Western Cape; 2020. Available from: http://hdl.handle.net/11394/7304

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

AUT University

14. Chen, Xi. The influence of FDI on China’s tourism industry .

Degree: 2010, AUT University

URL: http://hdl.handle.net/10292/904

► This study aims to analyze the influence of foreign direct investment in China’s tourism industry since the late 1970s, when the Government reopened China to… (more)

Subjects/Keywords: Foreign direct investment; Tourism industry; Comparative method; Case study

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APA (6^th Edition):

Chen, X. (2010). The influence of FDI on China’s tourism industry . (Thesis). AUT University. Retrieved from http://hdl.handle.net/10292/904

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

Chicago Manual of Style (16^th Edition):

Chen, Xi. “The influence of FDI on China’s tourism industry .” 2010. Thesis, AUT University. Accessed January 26, 2021. http://hdl.handle.net/10292/904.

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

MLA Handbook (7^th Edition):

Chen, Xi. “The influence of FDI on China’s tourism industry .” 2010. Web. 26 Jan 2021.

Vancouver:

Chen X. The influence of FDI on China’s tourism industry . [Internet] [Thesis]. AUT University; 2010. [cited 2021 Jan 26]. Available from: http://hdl.handle.net/10292/904.

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

Council of Science Editors:

Chen X. The influence of FDI on China’s tourism industry . [Thesis]. AUT University; 2010. Available from: http://hdl.handle.net/10292/904

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

Baylor University

15. Xu, Tian, 1988-. Application of direct current resistivity method to environmental and hydrological problems.

Degree: PhD, Baylor University. Dept. of Geosciences., 2016, Baylor University

URL: http://hdl.handle.net/2104/9618

► The direct current resistivity (DCR) method is a well-established geophysical method that is widely used in environmental, civil engineering, and hydrological investigations. DCR has the… (more)

Subjects/Keywords: Direct current resistivity. Electrical resistivity method. Electrical resistivity. Tomography.

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APA (6^th Edition):

Xu, Tian, 1. (2016). Application of direct current resistivity method to environmental and hydrological problems. (Doctoral Dissertation). Baylor University. Retrieved from http://hdl.handle.net/2104/9618

Chicago Manual of Style (16^th Edition):

Xu, Tian, 1988-. “Application of direct current resistivity method to environmental and hydrological problems.” 2016. Doctoral Dissertation, Baylor University. Accessed January 26, 2021. http://hdl.handle.net/2104/9618.

MLA Handbook (7^th Edition):

Xu, Tian, 1988-. “Application of direct current resistivity method to environmental and hydrological problems.” 2016. Web. 26 Jan 2021.

Vancouver:

Xu, Tian 1. Application of direct current resistivity method to environmental and hydrological problems. [Internet] [Doctoral dissertation]. Baylor University; 2016. [cited 2021 Jan 26]. Available from: http://hdl.handle.net/2104/9618.

Council of Science Editors:

Xu, Tian 1. Application of direct current resistivity method to environmental and hydrological problems. [Doctoral Dissertation]. Baylor University; 2016. Available from: http://hdl.handle.net/2104/9618

16. Lunden, Madelene. An evaluation of a newly developed method with required beneficial qualities for measuring pCO2 from fresh water : Test-study performed in a small boreal stream network, south west of Sweden during March – October 2013 and 2014.

Degree: Faculty of Arts and Sciences, 2015, Linköping UniversityLinköping University

URL: http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-118790

►

Studies have concluded that streams emit CO2, which indicates that natural sources of Greenhouse Gases can contribute to climate changefeedback. Why this is of… (more)

▼

Studies have concluded that streams emit CO2, which indicates that natural sources of Greenhouse Gases can contribute to climate changefeedback. Why this is of interest is to be able to make reliable climate models. These studies are however debated, since there are differentmethods to measure CO2 evasion from streams which conclude that different hydrological and chemical factors are affecting the gas exchange themost. It is based on an upside-down-placed chamber in the streams, containing a sensor which is able to directly measure the partial pressure ofCO2 (pCO2) in streams. An advantage with this method is that it is built on cheap equipment and therefore can be afforded to cover a bigcatchment with differing hydrological factors. The aim for the thesis is to evaluate the usefulness of this new method by running several statisticalanalyses on the collected data and also by comparing the trend from the statistical results to other methods statistical trends of pCO2. What can beconcluded by this study is that discharge affects the pCO2 in streams and it often appears with a negative correlation. Also, diurnal patterns ofpCO2 seem to appear, with a peak before lunch and minimum levels in the afternoon, which could indicate that pCO2 are dependent onphotosynthesis/respiration and/or temperature. These conclusions are of interest to understand how C acts in freshwater and respond to the climatechange. The study has to be extended with investigation of how more factors affect pCO2 and also some improvement for the method, before itcan be fully used.

Forskning har visat att små skogsbäckar släpper ut CO2 och på så sätt bidrar de till naturliga utsläpp av växthusgaser ochklimatförändringar. Studiernas resultat är dock debatterade då de till att börja med används olika metoder för att dra dessa slutsatser,vilka pekar på både olika kvantiter av CO2 utsläpp och också på olika påverkan från hydrologiska och kemiska faktorer. På grund avdetta har en alldeles ny metod utvecklats. Den grundar sig på en uppochnervänd kammare placerad i vatten som med hjälp av eninbyggd sensor fångar upp och mäter partialtrycket CO2 (pCO2) i vattnet. En fördel är att den är byggd av enkelt material til l lågt pris,vilket gör att metoden kan användas på många platser samtidigt, då man har råd med ett stort antal kammare. Målet för avhandlingenär att utvärdera nyttan av denna nya metod genom att köra flera statistiska analyser på de insamlade uppgifterna och även genom attjämföra utvecklingen från statistiska resultaten till andra metoder statistiska trender av pCO2. Studien kan visa att vattenhastighetenpåverkar pCO2 från bäckarna, och korrelationens struktur är betydande på vattennivån i bäcken. Man kan även dra slutsatser om attdet finns en dygnsrytm i hur CO2 släpps ut från bäckar med högsta utsläpp under förmiddagen och lägsta på eftermiddagen. Dettaskulle kunna bero på att CO2 utsläpp beror på fotosyntes/respiration och/eller temperaturskillnader. Dessa slutsatser är väldigtintressanta för att bygga på kunskapen om hur…

Subjects/Keywords: pCO2; direct measuring; new chamber method; required qualities

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

APA (6^th Edition):

Lunden, M. (2015). An evaluation of a newly developed method with required beneficial qualities for measuring pCO2 from fresh water : Test-study performed in a small boreal stream network, south west of Sweden during March – October 2013 and 2014. (Thesis). Linköping UniversityLinköping University. Retrieved from http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-118790

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

Chicago Manual of Style (16^th Edition):

Lunden, Madelene. “An evaluation of a newly developed method with required beneficial qualities for measuring pCO2 from fresh water : Test-study performed in a small boreal stream network, south west of Sweden during March – October 2013 and 2014.” 2015. Thesis, Linköping UniversityLinköping University. Accessed January 26, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-118790.

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

MLA Handbook (7^th Edition):

Lunden, Madelene. “An evaluation of a newly developed method with required beneficial qualities for measuring pCO2 from fresh water : Test-study performed in a small boreal stream network, south west of Sweden during March – October 2013 and 2014.” 2015. Web. 26 Jan 2021.

Vancouver:

Lunden M. An evaluation of a newly developed method with required beneficial qualities for measuring pCO2 from fresh water : Test-study performed in a small boreal stream network, south west of Sweden during March – October 2013 and 2014. [Internet] [Thesis]. Linköping UniversityLinköping University; 2015. [cited 2021 Jan 26]. Available from: http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-118790.

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

Council of Science Editors:

Lunden M. An evaluation of a newly developed method with required beneficial qualities for measuring pCO2 from fresh water : Test-study performed in a small boreal stream network, south west of Sweden during March – October 2013 and 2014. [Thesis]. Linköping UniversityLinköping University; 2015. Available from: http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-118790

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

University of the Western Cape

17. Cunnama, Daniel. Galaxy Evolution and Cosmology using Supercomputer Simulations by Daniel Cunnama .

Degree: 2013, University of the Western Cape

URL: http://hdl.handle.net/11394/4042

► Numerical simulations play a crucial role in testing current cosmological models of the formation and evolution of the cosmic structure observed in the modern Universe.… (more)

▼ Numerical simulations play a crucial role in testing current cosmological models of the formation and evolution of the cosmic structure observed in the modern Universe. Simulations of the collapse of both baryonic and non-baryonic matter under the influence of gravity have yielded important results in our understanding of the large scale structure of the Universe. In addition to the underlying large scale structure, simulations which include gas dynamics can give us valuable insight into, and allow us to make testable predictions on, the nature and distribution of baryonic matter on a wide range of scales. In this work we give an overview of cosmological simulations and the methods employed in the solution of many body problems. We then present three projects focusing on scales ranging from individual galaxies to the cosmic web connecting clusters of galaxies thereby demonstrating the potential and diversity of numerical simulations in the fields of cosmology and astrophysics. We firstly investigate the environmental dependance of neutral hydrogen in the intergalactic medium by utilising high resolution cosmological hydrodynamic simulations in Chapter 3. We find that the extent of the neutral hydrogen radial profile is dependant on both the environment of the galaxy and its classification within the group ie. whether it is a central or satellite galaxy. We investigate whether this effect could arise from ram pressure forces exerted on the galaxies and find good agreement between galaxies experiencing high ram pressure forces and those with a low neutral hydrogen content. In Chapter 4 we investigate the velocity–shape alignment of clusters in a dark matter only simulation and the effect of such an alignment on measurements of the kinetic Sunyaev–Zeldovich (kSZ) effect. We find an alignment not only exists but can lead to an enhancement in the kSZ signal of up to 60% when the cluster is orientated along the line-of-sight. Finally we attempt to identify shocked gas in clusters and filaments using intermediate resolution cosmological hydrodynamic simulations in Chapter 5 with a view to predicting the synchrotron emission from these areas, something that may be detectable with the Square Kilometer Array.

Subjects/Keywords: Dark matter; dark energy; direct method; particle mesh codes

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APA (6^th Edition):

Cunnama, D. (2013). Galaxy Evolution and Cosmology using Supercomputer Simulations by Daniel Cunnama . (Thesis). University of the Western Cape. Retrieved from http://hdl.handle.net/11394/4042

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

Chicago Manual of Style (16^th Edition):

Cunnama, Daniel. “Galaxy Evolution and Cosmology using Supercomputer Simulations by Daniel Cunnama .” 2013. Thesis, University of the Western Cape. Accessed January 26, 2021. http://hdl.handle.net/11394/4042.

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

MLA Handbook (7^th Edition):

Cunnama, Daniel. “Galaxy Evolution and Cosmology using Supercomputer Simulations by Daniel Cunnama .” 2013. Web. 26 Jan 2021.

Vancouver:

Cunnama D. Galaxy Evolution and Cosmology using Supercomputer Simulations by Daniel Cunnama . [Internet] [Thesis]. University of the Western Cape; 2013. [cited 2021 Jan 26]. Available from: http://hdl.handle.net/11394/4042.

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

Council of Science Editors:

Cunnama D. Galaxy Evolution and Cosmology using Supercomputer Simulations by Daniel Cunnama . [Thesis]. University of the Western Cape; 2013. Available from: http://hdl.handle.net/11394/4042

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

University of New South Wales

18. Bai, Siwei. Computational models of electroconvulsive therapy and transcranial direct current stimulation for treatment of depression.

Degree: Graduate School of Biomedical Engineering, 2012, University of New South Wales

URL: http://handle.unsw.edu.au/1959.4/52478 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:11151/SOURCE01?view=true

► Electroconvulsive therapy (ECT) and transcranial direct current stimulation (tDCS) are two important forms of transcranial electrical stimulation in clinical psychiatry. They have shown impressive therapeutic… (more)

▼ Electroconvulsive therapy (ECT) and transcranial direct current stimulation (tDCS) are two important forms of transcranial electrical stimulation in clinical psychiatry. They have shown impressive therapeutic results in the treatment of major depression and other psychiatric disorders. The aim of this thesis was to develop novel computational models of ECT and tDCS to assist in the further understanding of these two brain-stimulation techniques, to explore possible refinements and improvements in treatment efficacy.Head models of three different subjects were reconstructed from corresponding computed tomography (CT) or magnetic resonance imaging (MRI) scans. One was a low-resolution model rendered from a set of CT scans, incorporating skull conductivity anisotropy. The other two were high-resolution models reconstructed from MRI scans, with one incorporating white matter conductivity anisotropy. In both high-resolution models, several brain cortical regions of interest were segmented and defined; these are known to be involved in therapeutic or adverse stimulation outcomes. In one set of simulations, these structural head models were taken to be passive volume conductors, to investigate the effect of various electrode montages on the distribution of current density or electric field within the head. Results showed that current distribution in the brain was highly dependent on the electrode placement on the scalp. For example, when simulating three different right unilateral (RUL) ECT montages, the non-conventional montages with an electrode on the forehead appeared to have superiority over conventional RUL, because stimulation strength was stronger in regions believed responsible for the treatment efficacy, such as the anterior cingulate gyrus, and was weaker in regions that have been speculated to exert adverse effects, such as the hippocampus.In addition, a continuum active model of neural excitation was also developed to simulate direct activation of the brain following an ECT stimulus. This model was integrated into the passive head model to investigate the influence of different electrode placements, as well as the time-dependent effects of ECT stimulus parameters on brain activation. For instance, when the stimulus pulse width was reduced, maximum current density was unchanged but the spatial extent of activation was reduced. Moreover, results showed that stimulus frequency influenced the stimulus efficiency, that is, of all the brain neurons that were able to be directly activated by a single pulse, 80%, 10% and 0% were capable of being activated by both of two consecutive pulses with frequencies of 60 Hz, 90 Hz and 120 Hz, respectively. Advisors/Committee Members: Loo, Colleen, Psychiatry, Faculty of Medicine, UNSW.

Subjects/Keywords: Transcranial direct current stimulation; Finite element method; Electroconvulsive therapy

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APA (6^th Edition):

Bai, S. (2012). Computational models of electroconvulsive therapy and transcranial direct current stimulation for treatment of depression. (Doctoral Dissertation). University of New South Wales. Retrieved from http://handle.unsw.edu.au/1959.4/52478 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:11151/SOURCE01?view=true

Chicago Manual of Style (16^th Edition):

Bai, Siwei. “Computational models of electroconvulsive therapy and transcranial direct current stimulation for treatment of depression.” 2012. Doctoral Dissertation, University of New South Wales. Accessed January 26, 2021. http://handle.unsw.edu.au/1959.4/52478 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:11151/SOURCE01?view=true.

MLA Handbook (7^th Edition):

Bai, Siwei. “Computational models of electroconvulsive therapy and transcranial direct current stimulation for treatment of depression.” 2012. Web. 26 Jan 2021.

Vancouver:

Bai S. Computational models of electroconvulsive therapy and transcranial direct current stimulation for treatment of depression. [Internet] [Doctoral dissertation]. University of New South Wales; 2012. [cited 2021 Jan 26]. Available from: http://handle.unsw.edu.au/1959.4/52478 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:11151/SOURCE01?view=true.

Council of Science Editors:

Bai S. Computational models of electroconvulsive therapy and transcranial direct current stimulation for treatment of depression. [Doctoral Dissertation]. University of New South Wales; 2012. Available from: http://handle.unsw.edu.au/1959.4/52478 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:11151/SOURCE01?view=true

University of New South Wales

19. Yu, Chuan. The role of direct method operating cash flow disclosures in a voluntary setting.

Degree: Accounting, 2016, University of New South Wales

URL: http://handle.unsw.edu.au/1959.4/56696 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:41204/SOURCE02?view=true

► This thesis aims to enhance our understanding of the direct method operating cash flow disclosures through three inter-related studies. The first study focuses on understanding… (more)

▼ This thesis aims to enhance our understanding of the direct method operating cash flow disclosures through three inter-related studies. The first study focuses on understanding various lobbying positions taken on the issue of mandating the direct method operating cash flow disclosures. Comment letters submitted in response to the joint Discussion Paper issued by the IASB and FASB in 2008 are collected and reviewed. These comment letters are submitted by various types of respondents from all over the world, allowing researchers to conduct an in-depth analysis on their lobbying positions. Results from this study highlight the tension among various interested parties, especially between preparers and users. Preparers are the most active group in the lobbying process and they overall strongly object to the mandating of the direct method disclosures. In contrast, responses from the smaller sample of users show an overall positive attitude toward the adoption of the direct method.The second and the third study explore the determinants and usefulness of the direct method operating cash flow disclosures in a voluntary setting (the U.S.). The net benefits of disclosure choice can be viewed with higher clarity in such a setting, permitting a direct study of the attributes of firms most likely to benefit from such disclosures. In the second study, I explore firm-level attributes or economic settings associated with voluntarily adopting firms. In the third study, I investigate whether the disclosed direct method components in this voluntary setting are relatively and incrementally useful beyond the estimated analogues in predicting future operating cash flows and earnings. I further explore whether any incremental usefulness of the disclosed components varies under the different settings identified in the second study. The second study finds that firms are more likely to adopt the direct method when they have higher leverage, lower discretionary accruals, longer operating cycles, less complex business operations, and when they operate in a less competitive market. Furthermore, results from the third study show that the disclosed direct method components of operating cash flows are incrementally more useful in settings where firms have higher incentives to adopt the direct method. Advisors/Committee Members: Sidhu, Baljit, Accounting, Australian School of Business, UNSW.

Subjects/Keywords: Determinants and usefulness; The direct method; Statement of cash flows; Lobbying

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

APA (6^th Edition):

Yu, C. (2016). The role of direct method operating cash flow disclosures in a voluntary setting. (Doctoral Dissertation). University of New South Wales. Retrieved from http://handle.unsw.edu.au/1959.4/56696 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:41204/SOURCE02?view=true

Chicago Manual of Style (16^th Edition):

Yu, Chuan. “The role of direct method operating cash flow disclosures in a voluntary setting.” 2016. Doctoral Dissertation, University of New South Wales. Accessed January 26, 2021. http://handle.unsw.edu.au/1959.4/56696 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:41204/SOURCE02?view=true.

MLA Handbook (7^th Edition):

Yu, Chuan. “The role of direct method operating cash flow disclosures in a voluntary setting.” 2016. Web. 26 Jan 2021.

Vancouver:

Yu C. The role of direct method operating cash flow disclosures in a voluntary setting. [Internet] [Doctoral dissertation]. University of New South Wales; 2016. [cited 2021 Jan 26]. Available from: http://handle.unsw.edu.au/1959.4/56696 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:41204/SOURCE02?view=true.

Council of Science Editors:

Yu C. The role of direct method operating cash flow disclosures in a voluntary setting. [Doctoral Dissertation]. University of New South Wales; 2016. Available from: http://handle.unsw.edu.au/1959.4/56696 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:41204/SOURCE02?view=true

Boston University

20. Krishnan, Anush. Towards the study of flying snake aerodynamics, and an analysis of the direct forcing method.

Degree: PhD, Mechanical Engineering, 2015, Boston University

URL: http://hdl.handle.net/2144/15705

► Immersed boundary methods are a class of techniques in computational fluid dynamics where the Navier-Stokes equations are simulated on a computational grid that does not… (more)

▼ Immersed boundary methods are a class of techniques in computational fluid dynamics where the Navier-Stokes equations are simulated on a computational grid that does not conform to the interfaces in the domain of interest. This facilitates the simulation of flows with complex moving and deforming geometries without considerable effort wasted in generating the mesh. The first part of this dissertation is concerned with the aerodynamics of the cross-section of a species of flying snake, Chrysopelea paradisi (paradise tree snake). Past experiments have shown that the unique cross-section of this snake, which can be described as a lifting bluff body, produces an unusual lift curve – with a pronounced peak in lift coefficient at an angle of attack of 35 degrees for Reynolds numbers 9000 and beyond. We studied the aerodynamics of the cross-section using a 2-D immersed boundary method code. We were able to qualitatively reproduce the spike in the lift coefficient at the same angle of attack for flows beyond a Reynolds number of 2000. This phenomenon was associated with flow separation at the leading edge of the body that did not result in a stall. This produced a stronger vortex and an associated reduction in pressure on the dorsal surface of the snake cross-section, which resulted in higher lift. The second part of this work deals with the analysis of the direct forcing method, which is a popular immersed boundary method for flows with rigid boundaries. We begin with the fully discretized Navier-Stokes equations along with the appropriate boundary conditions applied at the solid boundary, and derive the fractional step method as an approximate block LU decomposition of this system. This results in an alternate formulation of the direct forcing method that takes into consideration mass conservation at the immersed boundaries and also handles the pressure boundary conditions more consistently. We demonstrate that this method is between first and second-order accurate in space when linear interpolation is used to enforce the boundary conditions on velocity. We then develop a theory for the order of accuracy of the direct forcing method with linear interpolation. For a simple 1-D case, we show that the method can converge at a range of rates for different locations of the solid body with respect to the mesh. But this effect averages out in higher dimensions and results in a scheme that has the same order of accuracy as the expected order of accuracy of the interpolation at the boundary. The discrete direct forcing method for the Navier-Stokes equations exhibits an order of accuracy between 1 and 2 because the velocities at the boundary are linearly interpolated, but the resulting boundary conditions on the pressure gradient turn out to be only first-order accurate. We recommend linearly interpolating the pressure gradient as well to make the method fully second-order accurate. We have also developed two open source codes in the course of these studies. The first, cuIBM, is a two-dimensional immersed boundary…

Subjects/Keywords: Mechanical engineering; Chrysopelea paradisi; Direct forcing method; Flying snakes; Fractional step method; Immersed boundary method; Lift enhancement

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APA (6^th Edition):

Krishnan, A. (2015). Towards the study of flying snake aerodynamics, and an analysis of the direct forcing method. (Doctoral Dissertation). Boston University. Retrieved from http://hdl.handle.net/2144/15705

Chicago Manual of Style (16^th Edition):

Krishnan, Anush. “Towards the study of flying snake aerodynamics, and an analysis of the direct forcing method.” 2015. Doctoral Dissertation, Boston University. Accessed January 26, 2021. http://hdl.handle.net/2144/15705.

MLA Handbook (7^th Edition):

Krishnan, Anush. “Towards the study of flying snake aerodynamics, and an analysis of the direct forcing method.” 2015. Web. 26 Jan 2021.

Vancouver:

Krishnan A. Towards the study of flying snake aerodynamics, and an analysis of the direct forcing method. [Internet] [Doctoral dissertation]. Boston University; 2015. [cited 2021 Jan 26]. Available from: http://hdl.handle.net/2144/15705.

Council of Science Editors:

Krishnan A. Towards the study of flying snake aerodynamics, and an analysis of the direct forcing method. [Doctoral Dissertation]. Boston University; 2015. Available from: http://hdl.handle.net/2144/15705

21. El Kanfoud, Ibtissam. Résolution de problèmes de rayonnement électromagnétique appliqués à l’imagerie médicale avec FreeFEM++ : Resolution of electromagnetic radiation problem applied to medical imaging with FreeFEM++.

Degree: Docteur es, Électronique, 2019, Université Côte d'Azur (ComUE)

URL: http://www.theses.fr/2019AZUR4000

► L'utilisation des microondes pour le diagnostic est en plein essor dans le domaine médical. Une des toutes dernières applications concerne la détection d'AVC (Accident vasculaire… (more)

▼ L'utilisation des microondes pour le diagnostic est en plein essor dans le domaine médical. Une des toutes dernières applications concerne la détection d'AVC (Accident vasculaire Cérébral) par imagerie microonde. La Société EMTensor GmbH basée à Vienne en Autriche étudie actuellement un tel système en collaboration avec le LEAT, le LJAD de l’Université Côte d’Azur et le LJLL de Sorbonne Université, pour le diagnostic et le contrôle de l'efficacité de traitement. Le but de ce travail était de modéliser le système de mesure de l'imagerie du cerveau, développé par la société EMTensor GmbH. Il s'agit d'un système d'émission/réception composé de 160 antennes disposées en 5 couronnes de 32 antennes réparties sur une cuve métallique cylindrique de section circulaire semi-ouverte. Un des enjeux majeurs de ce travail consiste en la modélisation et la simulation électromagnétique (EM) du système complet incluant un modèle réaliste de cerveau. La difficulté réside à la fois dans la taille du problème EM à simuler en raison du rapport entre la taille considérable du système et la taille très faible de certaines inhomogénéités à l’intérieur du cerveau, et dans la grande hétérogénéité des permittivités diélectriques présentes à l’intérieur du cerveau. Nous avons décidé d’utiliser un code open source, FreeFem++ pour cette modélisation car il permet de déployer du calcul hautement parallèle et la décomposition de domaines, qui sont bien adaptés à la complexité du problème EM. Dans un premier temps, nous avons comparé les résultats de simulation du système de mesure à vide (sans le cerveau) aux mesures et aux résultats obtenus par le logiciel de simulation EM HFSS basé sur la FEM comme FreeFem++. Nous avons ensuite simulé un modèle de tête tridimensionnel virtuel, à partir de coupe d’image du cerveau (scanner et IRM), en partenariat avec EMTensor en recherchant la position et le type d'AVC (ischémique et hémorragique). L'influence du bruit de mesure, la valeur du gel d'adaptation utilisé, le couplage entre les capteurs et le couplage entre la tête et les capteurs sont également étudiés. Afin de valider ces modèles, deux cas simples ont été étudiés. Un grand tube et un petit tube en plastique sont remplis de liquide d'adaptation symbolisant les caractéristiques diélectriques d'un cerveau afin de retrouver la forme du tube utilisé. Nous avons montré qu’il est possible de développer des algorithmes de reconstruction pour montrer permettant de retrouver la forme des objets par imagerie qualitative. Enfin, avec les partenaires et l'entreprise d'EMTensor nous avons appliqué une méthode quantitative à la détection d’un AVC ischémique par la tomographie microonde. Le problème direct repose sur l’utilisation de FreeFem++, en utilisant des éléments d'ordre supérieur et des préconditionneurs parallèles pour la méthode de décomposition de domaine. Nous avons résolu le problème inverse par un algorithme de minimisation, afin de reconstruire des images tomographiques du cerveau dans des temps compatibles avec les impératifs médicaux définis par… Advisors/Committee Members: Migliaccio, Claire (thesis director), Dolean, Victorita (thesis director).

Subjects/Keywords: Réseaux d'antennes; Problème direct; Microwave tomography; Antenna arrays; Direct problem; Inverse problem; Electromagnetic diffraction; Finite element method; Free FEM++

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

APA (6^th Edition):

El Kanfoud, I. (2019). Résolution de problèmes de rayonnement électromagnétique appliqués à l’imagerie médicale avec FreeFEM++ : Resolution of electromagnetic radiation problem applied to medical imaging with FreeFEM++. (Doctoral Dissertation). Université Côte d'Azur (ComUE). Retrieved from http://www.theses.fr/2019AZUR4000

Chicago Manual of Style (16^th Edition):

El Kanfoud, Ibtissam. “Résolution de problèmes de rayonnement électromagnétique appliqués à l’imagerie médicale avec FreeFEM++ : Resolution of electromagnetic radiation problem applied to medical imaging with FreeFEM++.” 2019. Doctoral Dissertation, Université Côte d'Azur (ComUE). Accessed January 26, 2021. http://www.theses.fr/2019AZUR4000.

MLA Handbook (7^th Edition):

El Kanfoud, Ibtissam. “Résolution de problèmes de rayonnement électromagnétique appliqués à l’imagerie médicale avec FreeFEM++ : Resolution of electromagnetic radiation problem applied to medical imaging with FreeFEM++.” 2019. Web. 26 Jan 2021.

Vancouver:

El Kanfoud I. Résolution de problèmes de rayonnement électromagnétique appliqués à l’imagerie médicale avec FreeFEM++ : Resolution of electromagnetic radiation problem applied to medical imaging with FreeFEM++. [Internet] [Doctoral dissertation]. Université Côte d'Azur (ComUE); 2019. [cited 2021 Jan 26]. Available from: http://www.theses.fr/2019AZUR4000.

Council of Science Editors:

El Kanfoud I. Résolution de problèmes de rayonnement électromagnétique appliqués à l’imagerie médicale avec FreeFEM++ : Resolution of electromagnetic radiation problem applied to medical imaging with FreeFEM++. [Doctoral Dissertation]. Université Côte d'Azur (ComUE); 2019. Available from: http://www.theses.fr/2019AZUR4000

22. Kang, Sangwoo. Direct sampling method in inverse electromagnetic scattering problem : Imagerie non itérative en problème inverse de diffraction des ondes : méthode DSM.

Degree: Docteur es, Génie électrique, 2019, Université Paris-Saclay (ComUE)

URL: http://www.theses.fr/2019SACLS417

►

Le problème de l'imagerie non itérative dans le cadre de la diffraction électromagnétique inverse utilisant la méthode d'échantillonnage direct (DSM) est considéré. Grâce à une… (more)

▼

Le problème de l'imagerie non itérative dans le cadre de la diffraction électromagnétique inverse utilisant la méthode d'échantillonnage direct (DSM) est considéré. Grâce à une combinaison de l'expression asymptotique du champ proche ou du champ lointain diffracté et de l'hypothèse de petits obstacles, les expressions analytiques de la fonction d'indicateur DSM sont présentées dans diverses configurations telles que des configurations 2D/3D, mono-/multi-configurations statiques, à vue limitée/complète et fréquence unique/ diversité en fréquence. Une fois l'expression analytique obtenue, sa structure est analysée et des améliorations proposées. Notre approche est validée à l’aide de données de simulation, et d’expériences le cas échéant. Premièrement, la structure mathématique du DSM à fréquence fixe en 2D dans divers problèmes de diffusion est établie, permettant une analyse théorique de son efficacité et de ses limites. Pour surmonter les limitations connues, une méthode alternative d'échantillonnage direct (DSMA) est proposée. Puis le cas multi-fréquence est investigué en introduisant et en analysant le DSM multi-fréquence (MDSM) et le DSMA multi-fréquence (MDSMA). Enfin, notre approche est étendue aux problèmes de diffraction électromagnétique inverse 3D pour lesquels le choix de la polarisation du dipôle de test est un paramètre clé. De par notre approche analytique, ce choix peut être effectué sur la base de la polarisation du champ incident.

The non-iterative imaging problem within the inverse electromagnetic scattering framework using the direct sampling method (DSM) is considered. Thanks to the combination of the asymptotic expression of the scattered near-field or far-field and of the small obstacle hypothesis the analytical expressions of the DSM indicator function are presented in various configurations such as 2D/3D configurations and/or mono-/multi-static configurations and/or limited-/full-view case and/or mono-/multi-frequency case. Once the analytical expression obtained, its structure is analyzed and improvements proposed. Our approach is validated using synthetic data and experimental ones when available. First, the mathematical structure of DSM at a fixed frequency in 2D various scattering problems is established allowing a theoretical analysis of its efficiency and limitations. To overcome the known limitations an alternative direct sampling method (DSMA) is proposed. Next, the multi-frequency case is investigated by introducing and analyzing the multi-frequency DSM (MDSM) and the multi-frequency DSMA (MDSMA).Finally, our approach is extended to 3D inverse electromagnetic scattering problems for which the choice of the polarization of the test dipole is a key parameter. Thanks to our analytical analysis it can be made based on the polarization of the incident field.

Advisors/Committee Members: Lambert, Marc (thesis director).

Subjects/Keywords: Méthode d'échantillonnage direct; Problème de diffusion électromagnétique inverse; Analyse mathématique; Direct sampling method; Inverse electromagnetic scattering problem; Mathematical analysis

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APA (6^th Edition):

Kang, S. (2019). Direct sampling method in inverse electromagnetic scattering problem : Imagerie non itérative en problème inverse de diffraction des ondes : méthode DSM. (Doctoral Dissertation). Université Paris-Saclay (ComUE). Retrieved from http://www.theses.fr/2019SACLS417

Chicago Manual of Style (16^th Edition):

Kang, Sangwoo. “Direct sampling method in inverse electromagnetic scattering problem : Imagerie non itérative en problème inverse de diffraction des ondes : méthode DSM.” 2019. Doctoral Dissertation, Université Paris-Saclay (ComUE). Accessed January 26, 2021. http://www.theses.fr/2019SACLS417.

MLA Handbook (7^th Edition):

Kang, Sangwoo. “Direct sampling method in inverse electromagnetic scattering problem : Imagerie non itérative en problème inverse de diffraction des ondes : méthode DSM.” 2019. Web. 26 Jan 2021.

Vancouver:

Kang S. Direct sampling method in inverse electromagnetic scattering problem : Imagerie non itérative en problème inverse de diffraction des ondes : méthode DSM. [Internet] [Doctoral dissertation]. Université Paris-Saclay (ComUE); 2019. [cited 2021 Jan 26]. Available from: http://www.theses.fr/2019SACLS417.

Council of Science Editors:

Kang S. Direct sampling method in inverse electromagnetic scattering problem : Imagerie non itérative en problème inverse de diffraction des ondes : méthode DSM. [Doctoral Dissertation]. Université Paris-Saclay (ComUE); 2019. Available from: http://www.theses.fr/2019SACLS417

23. Nagase, Denis Yudi. Estudo, in vitro, da influência da técnica e do aparelho de fotopolimerização na resistência de união de pinos intra-radiculares.

Degree: Mestrado, Dentística, 2010, University of São Paulo

URL: http://www.teses.usp.br/teses/disponiveis/23/23134/tde-22052010-094428/ ;

►

Objetivo: Este estudo se propõe a verificar a influencia do tipo de luz fotopolimerizadora na força de retenção de pinos intra-radiculares, tanto na técnica direta… (more)

▼

Objetivo: Este estudo se propõe a verificar a influencia do tipo de luz fotopolimerizadora na força de retenção de pinos intra-radiculares, tanto na técnica direta como na direta indireta. Métodos: 40 raízes de dentes bovinos com comprimento de 12 mm foram tratadas endodonticamente e divididas aleatoriamente em 4 grupos de acordo com a técnica de obtenção dos pinos e luz fotopolimerizadora (n=10): grupo 1 (técnica direta associada à lâmpada halogena); grupo 2 (técnica direta ao LED); grupo 3 (técnica direta-indireta associada à lampada halógena); e grupo 4 (técnica direta-indireta associada ao LED). A força de retenção foi determinada através do teste de tração usando Universal Testing Machine (Instron). Todos os dados foram analisados usando one-way analysis of variance (ANOVA) com a significância de p<0.05 e complementadas com teste de Tukey. Após o teste, as interfaces adesivas onde ocorreram as falhas foram examinadas e classificadas. Resultado: Os grupos 3 (246,05N ± 29,51) e 4 (241,60N ± 28,95) não apresentaram força de retenção estatisticamente diferente mas foram maiores que os grupos 1 (142,30N ± 25,60) e 2 (178,56N ± 25,67). A maior parte das fraturas ocorreu na interface dentina/resina. Conclusão: Com base nos resultados obtidos, concluímos que o método direto-indireto proporcionou a melhor retenção dos pinos de fibra de vidro.

Objectives: The purpose of this study is to verify the influence of light curing type on retention force of direct technique and direct-indirect technique. Methods: Fourth bovine single root teeth with 12mm of length were used in this study. The roots were endodontically treated and randomly divided in four groups according to the light curing unit and technique used: group 1(direct technique, halogen lamp), group 2(direct technique, LED), group 3(direct-indirect technique, halogen lamp), group 4(direct-indirect technique, lamp). The retention force was determined sing a Universal Testing Machine (Instron). All data were analyzed using one-way analysis of variance (ANOVA) and Tukey test. After the test, the failure was examined and classified according to the fracture place: post/ resin; resin/dentin; mix. Results: Group 3 (246,05N ± 29,51) and 4(241,60N ± 28,95)4 (95,18N) did not show statistically difference but presented higher retention force than group 1 (142,30N ± 25,60) and 2 (178,56N ± 25,67). Most of fracture occurred in interface between dentin/resin. Conclusion: Based on the obtained results, it was concluded that adhesive cementation technique influenced in the retention of glass fiber post.

Advisors/Committee Members: Oda, Margareth.

Subjects/Keywords: Direct method; Direct-indirect method; Fiber post; Força de retenção; Halogen lamp; Lâmpada halógena; LED; LED; Método direto; Método direto-indireto; Pinos de fibra; Retention force

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APA (6^th Edition):

Nagase, D. Y. (2010). Estudo, in vitro, da influência da técnica e do aparelho de fotopolimerização na resistência de união de pinos intra-radiculares. (Masters Thesis). University of São Paulo. Retrieved from http://www.teses.usp.br/teses/disponiveis/23/23134/tde-22052010-094428/ ;

Chicago Manual of Style (16^th Edition):

Nagase, Denis Yudi. “Estudo, in vitro, da influência da técnica e do aparelho de fotopolimerização na resistência de união de pinos intra-radiculares.” 2010. Masters Thesis, University of São Paulo. Accessed January 26, 2021. http://www.teses.usp.br/teses/disponiveis/23/23134/tde-22052010-094428/ ;.

MLA Handbook (7^th Edition):

Nagase, Denis Yudi. “Estudo, in vitro, da influência da técnica e do aparelho de fotopolimerização na resistência de união de pinos intra-radiculares.” 2010. Web. 26 Jan 2021.

Vancouver:

Nagase DY. Estudo, in vitro, da influência da técnica e do aparelho de fotopolimerização na resistência de união de pinos intra-radiculares. [Internet] [Masters thesis]. University of São Paulo; 2010. [cited 2021 Jan 26]. Available from: http://www.teses.usp.br/teses/disponiveis/23/23134/tde-22052010-094428/ ;.

Council of Science Editors:

Nagase DY. Estudo, in vitro, da influência da técnica e do aparelho de fotopolimerização na resistência de união de pinos intra-radiculares. [Masters Thesis]. University of São Paulo; 2010. Available from: http://www.teses.usp.br/teses/disponiveis/23/23134/tde-22052010-094428/ ;

NSYSU

24. Chou, Po-hao. Modeling and Temperature Control of a Cooling Machine with Hot Gas Bypass.

Degree: Master, Electrical Engineering, 2017, NSYSU

URL: http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0023117-160520

► This thesis aims at controlling the temperature of an industrial water-cooling machine to a high precision even under constantly changing thermal load. The cooling water… (more)

Subjects/Keywords: Anti-windup feedback; water-cooling machine; least squares method; gain scheduling compensator; feedforward compensator; direct Synthesis method; PID controller

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

APA (6^th Edition):

Chou, P. (2017). Modeling and Temperature Control of a Cooling Machine with Hot Gas Bypass. (Thesis). NSYSU. Retrieved from http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0023117-160520

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

Chicago Manual of Style (16^th Edition):

Chou, Po-hao. “Modeling and Temperature Control of a Cooling Machine with Hot Gas Bypass.” 2017. Thesis, NSYSU. Accessed January 26, 2021. http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0023117-160520.

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

MLA Handbook (7^th Edition):

Chou, Po-hao. “Modeling and Temperature Control of a Cooling Machine with Hot Gas Bypass.” 2017. Web. 26 Jan 2021.

Vancouver:

Chou P. Modeling and Temperature Control of a Cooling Machine with Hot Gas Bypass. [Internet] [Thesis]. NSYSU; 2017. [cited 2021 Jan 26]. Available from: http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0023117-160520.

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

Council of Science Editors:

Chou P. Modeling and Temperature Control of a Cooling Machine with Hot Gas Bypass. [Thesis]. NSYSU; 2017. Available from: http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0023117-160520

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

Texas A&M University

25. Karagoz, Secgin. Process Design, Simulation and Integration of Dimethyl Ether (DME) Production from Shale Gas by Direct and Indirect Methods.

Degree: MS, Chemical Engineering, 2014, Texas A&M University

URL: http://hdl.handle.net/1969.1/153529

► As the energy demand is increasing constantly, sustainable energy resources are needed to meet this demand and enable economic stability. In order to attain this… (more)

▼ As the energy demand is increasing constantly, sustainable energy resources are needed to meet this demand and enable economic stability. In order to attain this goal, researchers continue to develop new technologies and methods in the field of sustainable energy. Over the last decade, the U.S has witnessed substantial growth in shale gas production. Consequently, shale gas has become a competitive feedstock for usage as energy and production of chemicals and petrochemicals. A valuable product which may be obtained from shale gas is dimethyl ether (DME). Dimethyl ether can be used in many areas such as power generation, transportation fuel, and domestic heating and cooking. Dimethyl ether is currently produced from natural gas, coal and biomass through synthesis gas as an intermediate. Recently, the attention to DME has increased because of its potential in addressing energy security and environmental problems. DME is produced conventionally through two steps (indirect process) which are methanol synthesis and dehydration of the methanol to DME. Another way to produce DME is the direct synthesis of DME from syngas. In order to use DME as a fuel alternative, it must be produced at low cost in large quantities. The purpose of this study is to develop a process synthesis, simulation, and integration of a shale gas-to-DME plant by direct and indirect methods. Techno-economic analysis is carried out to assess the profitability of the base-case processes under current market conditions. A sensitivity analysis is also conducted to evaluate the process profitability under variable market conditions. Finally, the both methods are compared in terms of the fixed capital cost, operating cost, return on investment, and CO_(2) and water impact. Indirect and direct process simulation of commercial DME plant was carried out by Aspen Plus. The shale gas feedstock was taken from one of the wells in Barnett shale play. The DME production capacities of the base cases for the direct and indirect processes were set to 3,250 tonnes per day. The direct and indirect process flowsheets were synthesized using five and seven main processing steps, respectively. Pinch analysis was used to conduct heat integration of the process. As a result of study, it was found that the direct method has advantage over the indirect method in terms of the fixed capital cost, operating cost, return on investment, and CO_(2) impact. The capital investment of the direct production method is 25% less than the indirect method. The direct method is more economically attractive than the indirect method. When a sensitivity analysis is considered, the prices of methanol and shale gas are the most important factors impacting the operating cost. The contribution of energy integration on the ROI of the direct method is approximately 2.25%. The ROI of the indirect method is improved by 1.83% after energy integration. In contrast to the other criteria, the indirect way has significant advantage over the direct way by producing almost 1760 ton/d water. The direct method… Advisors/Committee Members: El-Halwagi, Mahmoud M. (advisor), Mannan, M. Sam (committee member), Nasr-El-Din, Hisham (committee member).

Subjects/Keywords: Shale gas; Natural gas; Dimethyl ether; Direct Method; Indirect Method; Process integration; Process simulation; Techno-economic analysis; Barnett Shale

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APA (6^th Edition):

Karagoz, S. (2014). Process Design, Simulation and Integration of Dimethyl Ether (DME) Production from Shale Gas by Direct and Indirect Methods. (Masters Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/153529

Chicago Manual of Style (16^th Edition):

Karagoz, Secgin. “Process Design, Simulation and Integration of Dimethyl Ether (DME) Production from Shale Gas by Direct and Indirect Methods.” 2014. Masters Thesis, Texas A&M University. Accessed January 26, 2021. http://hdl.handle.net/1969.1/153529.

MLA Handbook (7^th Edition):

Karagoz, Secgin. “Process Design, Simulation and Integration of Dimethyl Ether (DME) Production from Shale Gas by Direct and Indirect Methods.” 2014. Web. 26 Jan 2021.

Vancouver:

Karagoz S. Process Design, Simulation and Integration of Dimethyl Ether (DME) Production from Shale Gas by Direct and Indirect Methods. [Internet] [Masters thesis]. Texas A&M University; 2014. [cited 2021 Jan 26]. Available from: http://hdl.handle.net/1969.1/153529.

Council of Science Editors:

Karagoz S. Process Design, Simulation and Integration of Dimethyl Ether (DME) Production from Shale Gas by Direct and Indirect Methods. [Masters Thesis]. Texas A&M University; 2014. Available from: http://hdl.handle.net/1969.1/153529

Washington State University

26. [No author]. Measurements of Gaseous Emissions from Naturally Ventilated Livestock Barns .

Degree: 2015, Washington State University

URL: http://hdl.handle.net/2376/6206

► Agriculture contributes over 80% of national NH3 emission and ~55% is attributed to animal livestock operations. Livestock barns are one of the major emission sources… (more)

▼ Agriculture contributes over 80% of national NH3 emission and ~55% is attributed to animal livestock operations. Livestock barns are one of the major emission sources due to their large footprint. Therefore, a pressing need exists to develop effective emissions mitigation techniques. However, lack of reliable emission measuring techniques, especially for naturally ventilated (NV) livestock barns, impedes development of effective strategies for mitigating emissions. Furthermore, multiple inlets and outlets associated with NV animal housing and unstable ambient meteorology presents a huge challenge in the determination of ventilation rate.Due to high investment in use of the direct method, indirect methods are preferably used for determining ventilation rates in NV animal buildings. In this thesis, two widely used indirect methods (CO2-balance and H2O-balance method) were evaluated against a direct method. The results revealed that CO2-balance method overestimated barn air exchange rates (AER), while H2O-balance method underestimated the AER. Integration time and wind velocity, on the other hand, had significant effects on both indirect methods. The two indirect methods also were not reliable during milking time or at low indoor-outdoor differences in temperatures, absolute humidity, and CO2 concentrations.In view of complexity of current direct methods, two simple direct methods were developed and determined to be suitable for AER measurement with marginal relative errors. The two methods were based on measurements of wind speed at a local weather tower or at only one location adjacent to the center of the barn. The third simple approach, via CO2-balance method, evaluated two gas-sampling regimes: indoor-outdoor and perimeter samplings. The results showed no significant differences between the two sampling regimes. The indoor-outdoor sampling regime was thus recommended because of its cost-effectiveness.The last research component was the search for robust but simple and reliable devices for determining NH3 concentrations in NV dairy barns. Towards this effort, two passive samplers, Ogawa passive sampler (Ogawa) and passive flux sampler (PFS), were evaluated against a photoacoustic infrared spectroscope (INNOVA). Results indicated that the two passive samplers are reliable alternatives to the sophisticated and expensive INNOVA for up to three-days continuous monitoring of NH3 concentrations in NV dairy barns. Advisors/Committee Members: Ndegwa, Pius M (advisor).

Subjects/Keywords: Environmental engineering; Agriculture engineering; direct method; emission rate; gas concentration; indirect method; naturally ventilation; ventilation rate

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APA (6^th Edition):

author], [. (2015). Measurements of Gaseous Emissions from Naturally Ventilated Livestock Barns . (Thesis). Washington State University. Retrieved from http://hdl.handle.net/2376/6206

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

Chicago Manual of Style (16^th Edition):

author], [No. “Measurements of Gaseous Emissions from Naturally Ventilated Livestock Barns .” 2015. Thesis, Washington State University. Accessed January 26, 2021. http://hdl.handle.net/2376/6206.

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

MLA Handbook (7^th Edition):

author], [No. “Measurements of Gaseous Emissions from Naturally Ventilated Livestock Barns .” 2015. Web. 26 Jan 2021.

Vancouver:

author] [. Measurements of Gaseous Emissions from Naturally Ventilated Livestock Barns . [Internet] [Thesis]. Washington State University; 2015. [cited 2021 Jan 26]. Available from: http://hdl.handle.net/2376/6206.

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

Council of Science Editors:

author] [. Measurements of Gaseous Emissions from Naturally Ventilated Livestock Barns . [Thesis]. Washington State University; 2015. Available from: http://hdl.handle.net/2376/6206

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

Brno University of Technology

27. Šenk, Vít. Keramické materiály s pěnovou strukturou: Ceramic materials with foam structure.

Degree: 2019, Brno University of Technology

URL: http://hdl.handle.net/11012/7445

► Bachelor’s thesis is concerned to preparation ceramic materials with a foam structure suitable for supporting, catalytic and biological applications. A part of work is focused… (more)

Subjects/Keywords: Keramické pěny; otevřená pórovitost; templátová metoda; metoda přímého pěnění; Foam ceramic; cellular ceramic; open porosity; replica method; direct foaming method

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APA (6^th Edition):

Šenk, V. (2019). Keramické materiály s pěnovou strukturou: Ceramic materials with foam structure. (Thesis). Brno University of Technology. Retrieved from http://hdl.handle.net/11012/7445

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

Chicago Manual of Style (16^th Edition):

Šenk, Vít. “Keramické materiály s pěnovou strukturou: Ceramic materials with foam structure.” 2019. Thesis, Brno University of Technology. Accessed January 26, 2021. http://hdl.handle.net/11012/7445.

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

MLA Handbook (7^th Edition):

Šenk, Vít. “Keramické materiály s pěnovou strukturou: Ceramic materials with foam structure.” 2019. Web. 26 Jan 2021.

Vancouver:

Šenk V. Keramické materiály s pěnovou strukturou: Ceramic materials with foam structure. [Internet] [Thesis]. Brno University of Technology; 2019. [cited 2021 Jan 26]. Available from: http://hdl.handle.net/11012/7445.

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

Council of Science Editors:

Šenk V. Keramické materiály s pěnovou strukturou: Ceramic materials with foam structure. [Thesis]. Brno University of Technology; 2019. Available from: http://hdl.handle.net/11012/7445

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

Delft University of Technology

28. Yang, Boyuan (author). Comparisons of implicit and explicit time integration methods in finite element analysis for linear elastic material and quasi-brittle material in dynamic problems.

Degree: 2019, Delft University of Technology

URL: http://resolver.tudelft.nl/uuid:3bf6605b-c108-4de8-a5fa-6305f7321ff4

► In finite element analysis, nonlinear time-history analysis is a realistic and accurate analysis type for dynamic or seismic analysis due to its solutions contain wealthy… (more)

▼ In finite element analysis, nonlinear time-history analysis is a realistic and accurate analysis type for dynamic or seismic analysis due to its solutions contain wealthy data and complete response time-history. The most commonly used method, probably the only practical procedure, in nonlinear time-history analysis is the direct time integration method. In general, every direct time integration method could be classified as either an implicit method or an explicit method. Understanding the differences between the two categories in both theoretical and practical aspects is very important for engineers to make the best analysis strategy for a specific dynamic or seismic analysis. In this treatise, the most popular method in each category, i.e., implicit Newmark method and explicit central difference method, will be introduced and used in transient analyses and results comparisons. In total, five cases studies are included in this thesis, including three cases with linear elastic materials and two cases with quasi-brittle masonry material. These five cases are studied to answer the main research questions of this research: What differences can be observed in comparisons of solutions obtained from implicit and explicit methods for linear elastic material in transient analysis and for quasi-brittle material under seismic load? Also, how are the performances of both methods with respect to the stability and accuracy aspects? The results comparisons show that for linear elastic material, both methods could generate accurate solutions with proper time steps. However, the explicit method shows a better representation of the high-frequency response of the structure. For quasi-brittle masonry material, both methods are possible to generate good results. However, the implicit method may have convergence problems during the iterations, which could lead to inaccurate predictions of nonlinear behavior of the structure. The explicit method shows very good predictions for nonlinear behavior, but the computation time is quite long and the critical time step is highly influenced by many factors in the finite element model. Moreover, the mass scaling technique, which is generally used in the explicit method, is also investigated in this thesis. Advisors/Committee Members: Hendriks, Max (mentor), Rots, Jan (graduation committee), Tsouvalas, Apostolos (graduation committee), Schreppers, G.M.A (graduation committee), Delft University of Technology (degree granting institution).

Subjects/Keywords: Finite Element Analysis; DIANA FEA; Direct time integration; Implicit method; Explicit method; Nonlinear Dynamics; Masonry material

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APA (6^th Edition):

Yang, B. (. (2019). Comparisons of implicit and explicit time integration methods in finite element analysis for linear elastic material and quasi-brittle material in dynamic problems. (Masters Thesis). Delft University of Technology. Retrieved from http://resolver.tudelft.nl/uuid:3bf6605b-c108-4de8-a5fa-6305f7321ff4

Chicago Manual of Style (16^th Edition):

Yang, Boyuan (author). “Comparisons of implicit and explicit time integration methods in finite element analysis for linear elastic material and quasi-brittle material in dynamic problems.” 2019. Masters Thesis, Delft University of Technology. Accessed January 26, 2021. http://resolver.tudelft.nl/uuid:3bf6605b-c108-4de8-a5fa-6305f7321ff4.

MLA Handbook (7^th Edition):

Yang, Boyuan (author). “Comparisons of implicit and explicit time integration methods in finite element analysis for linear elastic material and quasi-brittle material in dynamic problems.” 2019. Web. 26 Jan 2021.

Vancouver:

Yang B(. Comparisons of implicit and explicit time integration methods in finite element analysis for linear elastic material and quasi-brittle material in dynamic problems. [Internet] [Masters thesis]. Delft University of Technology; 2019. [cited 2021 Jan 26]. Available from: http://resolver.tudelft.nl/uuid:3bf6605b-c108-4de8-a5fa-6305f7321ff4.

Council of Science Editors:

Yang B(. Comparisons of implicit and explicit time integration methods in finite element analysis for linear elastic material and quasi-brittle material in dynamic problems. [Masters Thesis]. Delft University of Technology; 2019. Available from: http://resolver.tudelft.nl/uuid:3bf6605b-c108-4de8-a5fa-6305f7321ff4

University of Texas – Austin

29. Koo, Heeseok. Large-eddy simulations of scramjet engines.

Degree: PhD, Aerospace Engineering, 2011, University of Texas – Austin

URL: http://hdl.handle.net/2152/ETD-UT-2011-05-3203

► The main objective of this dissertation is to develop large-eddy simulation (LES) based computational tools for supersonic inlet and combustor design. In the recent past,… (more)

▼ The main objective of this dissertation is to develop large-eddy simulation (LES) based computational tools for supersonic inlet and combustor design. In the recent past, LES methodology has emerged as a viable tool for modeling turbulent combustion. LES computes the large scale mixing process accurately, thereby providing a better starting point for small-scale models that describe the combustion process. In fact, combustion models developed in the context of Reynolds-averaged Navier Stokes (RANS) equations exhibit better predictive capability when used in the LES framework. The development of a predictive computational tool based on LES will provide a significant boost to the design of scramjet engines. Although LES has been used widely in the simulation of subsonic turbulent flows, its application to high-speed flows has been hampered by a variety of modeling and numerical issues. In this work, we develop a comprehensive LES methodology for supersonic flows, focusing on the simulation of scramjet engine components. This work is divided into three sections. First, a robust compressible flow solver for a generalized high-speed flow configuration is developed. By using carefully designed numerical schemes, dissipative errors associated with discretization methods for high-speed flows are minimized. Multiblock and immersed boundary method are used to handle scramjet-specific geometries. Second, a new combustion model for compressible reactive flows is developed. Subsonic combustion models are not directly applicable in high-speed flows due to the coupling between the energy and velocity fields. Here, a probability density function (PDF) approach is developed for high-speed combustion. This method requires solution to a high dimensional PDF transport equation, which is achieved through a novel direct quadrature method of moments (DQMOM). The combustion model is validated using experiments on supersonic reacting flows. Finally, the LES methodology is used to study the inlet-isolator component of a dual-mode scramjet. The isolator is a critical component that maintains the compression shock structures required for stable combustor operation in ramjet mode. We simulate unsteady dynamics inside an experimental isolator, including the propagation of an unstart event that leads to loss of compression. Using a suite of simulations, the sensitivity of the results to LES models and numerical implementation is studied. Advisors/Committee Members: Raman, Venkat (advisor), Varghese, Philip L. (committee member), Clemens, Noel T. (committee member), Moser, Robert D. (committee member), Ezekoye, Ofodike A. (committee member).

Subjects/Keywords: Large-eddy simulations; Combustion model; DQMOM; Direct quadrature method of moments; Compressible flow; Shock capturing method; Hyperviscosity; Scramjet; Inlet-isolator; Unstart

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

APA (6^th Edition):

Koo, H. (2011). Large-eddy simulations of scramjet engines. (Doctoral Dissertation). University of Texas – Austin. Retrieved from http://hdl.handle.net/2152/ETD-UT-2011-05-3203

Chicago Manual of Style (16^th Edition):

Koo, Heeseok. “Large-eddy simulations of scramjet engines.” 2011. Doctoral Dissertation, University of Texas – Austin. Accessed January 26, 2021. http://hdl.handle.net/2152/ETD-UT-2011-05-3203.

MLA Handbook (7^th Edition):

Koo, Heeseok. “Large-eddy simulations of scramjet engines.” 2011. Web. 26 Jan 2021.

Vancouver:

Koo H. Large-eddy simulations of scramjet engines. [Internet] [Doctoral dissertation]. University of Texas – Austin; 2011. [cited 2021 Jan 26]. Available from: http://hdl.handle.net/2152/ETD-UT-2011-05-3203.

Council of Science Editors:

Koo H. Large-eddy simulations of scramjet engines. [Doctoral Dissertation]. University of Texas – Austin; 2011. Available from: http://hdl.handle.net/2152/ETD-UT-2011-05-3203

Universidade Nova

30. Simões, Flávio Manuel Vilas-Boas. Does direct cash flow presentation help in predicting future operating cash flow?.

Degree: 2012, Universidade Nova

URL: http://www.rcaap.pt/detail.jsp?id=oai:run.unl.pt:10362/9526

►

A Work Project, presented as part of the requirements for the Award of a Masters Degree in Finance from the NOVA – School of Business… (more)

Subjects/Keywords: Operating cash flows; Direct method; Financial statement presentation; IAS 7; Estimation errors

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APA (6^th Edition):

Simões, F. M. V. (2012). Does direct cash flow presentation help in predicting future operating cash flow?. (Thesis). Universidade Nova. Retrieved from http://www.rcaap.pt/detail.jsp?id=oai:run.unl.pt:10362/9526

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

Chicago Manual of Style (16^th Edition):

Simões, Flávio Manuel Vilas-Boas. “Does direct cash flow presentation help in predicting future operating cash flow?.” 2012. Thesis, Universidade Nova. Accessed January 26, 2021. http://www.rcaap.pt/detail.jsp?id=oai:run.unl.pt:10362/9526.

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

MLA Handbook (7^th Edition):

Simões, Flávio Manuel Vilas-Boas. “Does direct cash flow presentation help in predicting future operating cash flow?.” 2012. Web. 26 Jan 2021.

Vancouver:

Simões FMV. Does direct cash flow presentation help in predicting future operating cash flow?. [Internet] [Thesis]. Universidade Nova; 2012. [cited 2021 Jan 26]. Available from: http://www.rcaap.pt/detail.jsp?id=oai:run.unl.pt:10362/9526.

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

Council of Science Editors:

Simões FMV. Does direct cash flow presentation help in predicting future operating cash flow?. [Thesis]. Universidade Nova; 2012. Available from: http://www.rcaap.pt/detail.jsp?id=oai:run.unl.pt:10362/9526

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

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Open Access Theses and Dissertations