+publisher:"King Abdullah University of Science and Technology" +contributor:("Keyes, David E.")

King Abdullah University of Science and Technology

1. AlOnazi, Amani. Design and Optimization of OpenFOAM-based CFD Applications for Modern Hybrid and Heterogeneous HPC Platforms.

Degree: Computer, Electrical and Mathematical Sciences and Engineering (CEMSE) Division, 2014, King Abdullah University of Science and Technology

URL: http://hdl.handle.net/10754/316389

► The progress of high performance computing platforms is dramatic, and most of the simulations carried out on these platforms result in improvements on one level,… (more)

Subjects/Keywords: hybrid multi GPU; Conjugate Gradient; Open FOAM; Multicore Solver

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APA (6^th Edition):

AlOnazi, A. (2014). Design and Optimization of OpenFOAM-based CFD Applications for Modern Hybrid and Heterogeneous HPC Platforms. (Thesis). King Abdullah University of Science and Technology. Retrieved from http://hdl.handle.net/10754/316389

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):

AlOnazi, Amani. “Design and Optimization of OpenFOAM-based CFD Applications for Modern Hybrid and Heterogeneous HPC Platforms.” 2014. Thesis, King Abdullah University of Science and Technology. Accessed April 12, 2021. http://hdl.handle.net/10754/316389.

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

MLA Handbook (7^th Edition):

AlOnazi, Amani. “Design and Optimization of OpenFOAM-based CFD Applications for Modern Hybrid and Heterogeneous HPC Platforms.” 2014. Web. 12 Apr 2021.

Vancouver:

AlOnazi A. Design and Optimization of OpenFOAM-based CFD Applications for Modern Hybrid and Heterogeneous HPC Platforms. [Internet] [Thesis]. King Abdullah University of Science and Technology; 2014. [cited 2021 Apr 12]. Available from: http://hdl.handle.net/10754/316389.

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

Council of Science Editors:

AlOnazi A. Design and Optimization of OpenFOAM-based CFD Applications for Modern Hybrid and Heterogeneous HPC Platforms. [Thesis]. King Abdullah University of Science and Technology; 2014. Available from: http://hdl.handle.net/10754/316389

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

King Abdullah University of Science and Technology

2. Alghamdi, Amal Mohammed. PetClaw: Parallelization and Performance Optimization of a Python-Based Nonlinear Wave Propagation Solver Using PETSc.

Degree: Computer, Electrical and Mathematical Sciences and Engineering (CEMSE) Division, 2012, King Abdullah University of Science and Technology

URL: http://hdl.handle.net/10754/229271

► Clawpack, a conservation laws package implemented in Fortran, and its Python-based version, PyClaw, are existing tools providing nonlinear wave propagation solvers that use state of… (more)

▼ Clawpack, a conservation laws package implemented in Fortran, and its Python-based version, PyClaw, are existing tools providing nonlinear wave propagation solvers that use state of the art finite volume methods. Simulations using those tools can have extensive computational requirements to provide accurate results. Therefore, a number of tools, such as BearClaw and MPIClaw, have been developed based on Clawpack to achieve significant speedup by exploiting parallel architectures. However, none of them has been shown to scale on a large number of cores. Furthermore, these tools, implemented in Fortran, achieve parallelization by inserting parallelization logic and MPI standard routines throughout the serial code in a non modular manner. Our contribution in this thesis research is three-fold. First, we demonstrate an advantageous use case of Python in implementing easy-to-use modular extensible scalable scientific software tools by developing an implementation of a parallelization framework, PetClaw, for PyClaw using the well-known Portable Extensible Toolkit for Scientific Computation, PETSc, through its Python wrapper petsc4py. Second, we demonstrate the possibility of getting acceptable Python code performance when compared to Fortran performance after introducing a number of serial optimizations to the Python code including integrating Clawpack Fortran kernels into PyClaw for low-level computationally intensive parts of the code. As a result of those optimizations, the Python overhead in PetClaw for a shallow water application is only 12 percent when compared to the corresponding Fortran Clawpack application. Third, we provide a demonstration of PetClaw scalability on up to the entirety of Shaheen; a 16-rack Blue Gene/P IBM supercomputer that comprises 65,536 cores and located at King Abdullah University of Science and Technology (KAUST). The PetClaw solver achieved above 0.98 weak scaling efficiency for an Euler application on the whole machine excluding the initialization overhead that is less significant in potential long runs of PetClaw applications. The solver also achieved superlinear strong scaling efficiency for an acoustics application on 1,024 cores. Furthermore, we provide reproducibility information for all the computational experiments presented in this thesis. Advisors/Committee Members: Ketcheson, David I. (advisor), Ahmadia, Aron (committee member), Keyes, David E. (committee member).

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APA (6^th Edition):

Alghamdi, A. M. (2012). PetClaw: Parallelization and Performance Optimization of a Python-Based Nonlinear Wave Propagation Solver Using PETSc. (Thesis). King Abdullah University of Science and Technology. Retrieved from http://hdl.handle.net/10754/229271

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):

Alghamdi, Amal Mohammed. “PetClaw: Parallelization and Performance Optimization of a Python-Based Nonlinear Wave Propagation Solver Using PETSc.” 2012. Thesis, King Abdullah University of Science and Technology. Accessed April 12, 2021. http://hdl.handle.net/10754/229271.

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

MLA Handbook (7^th Edition):

Alghamdi, Amal Mohammed. “PetClaw: Parallelization and Performance Optimization of a Python-Based Nonlinear Wave Propagation Solver Using PETSc.” 2012. Web. 12 Apr 2021.

Vancouver:

Alghamdi AM. PetClaw: Parallelization and Performance Optimization of a Python-Based Nonlinear Wave Propagation Solver Using PETSc. [Internet] [Thesis]. King Abdullah University of Science and Technology; 2012. [cited 2021 Apr 12]. Available from: http://hdl.handle.net/10754/229271.

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

Council of Science Editors:

Alghamdi AM. PetClaw: Parallelization and Performance Optimization of a Python-Based Nonlinear Wave Propagation Solver Using PETSc. [Thesis]. King Abdullah University of Science and Technology; 2012. Available from: http://hdl.handle.net/10754/229271

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

King Abdullah University of Science and Technology

3. Hidayah, Lailatul. VarB Plus: An Integrated Tool for Visualization of Genome Variation Datasets.

Degree: Computer, Electrical and Mathematical Sciences and Engineering (CEMSE) Division, 2012, King Abdullah University of Science and Technology

URL: http://hdl.handle.net/10754/244612

► Research on genomic sequences has been improving significantly as more advanced technology for sequencing has been developed. This opens enormous opportunities for sequence analysis. Various… (more)

▼ Research on genomic sequences has been improving significantly as more advanced technology for sequencing has been developed. This opens enormous opportunities for sequence analysis. Various analytical tools have been built for purposes such as sequence assembly, read alignments, genome browsing, comparative genomics, and visualization. From the visualization perspective, there is an increasing trend towards use of large-scale computation. However, more than power is required to produce an informative image. This is a challenge that we address by providing several ways of representing biological data in order to advance the inference endeavors of biologists. This thesis focuses on visualization of variations found in genomic sequences. We develop several visualization functions and embed them in an existing variation visualization tool as extensions. The tool we improved is named VarB, hence the nomenclature for our enhancement is VarB Plus. To the best of our knowledge, besides VarB, there is no tool that provides the capability of dynamic visualization of genome variation datasets as well as statistical analysis. Dynamic visualization allows users to toggle different parameters on and off and see the results on the fly. The statistical analysis includes Fixation Index, Relative Variant Density, and Tajima’s D. Hence we focused our efforts on this tool. The scope of our work includes plots of per-base genome coverage, Principal Coordinate Analysis (PCoA), integration with a read alignment viewer named LookSeq, and visualization of geo-biological data. In addition to description of embedded functionalities, significance, and limitations, future improvements are discussed. The result is four extensions embedded successfully in the original tool, which is built on the Qt framework in C++. Hence it is portable to numerous platforms. Our extensions have shown acceptable execution time in a beta testing with various high-volume published datasets, as well as positive feedback from several researchers in the field in terms of their usability and significance. Advisors/Committee Members: Pain, Arnab (advisor), Gao, Xin (committee member), Keyes, David E. (committee member).

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APA (6^th Edition):

Hidayah, L. (2012). VarB Plus: An Integrated Tool for Visualization of Genome Variation Datasets. (Thesis). King Abdullah University of Science and Technology. Retrieved from http://hdl.handle.net/10754/244612

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):

Hidayah, Lailatul. “VarB Plus: An Integrated Tool for Visualization of Genome Variation Datasets.” 2012. Thesis, King Abdullah University of Science and Technology. Accessed April 12, 2021. http://hdl.handle.net/10754/244612.

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

MLA Handbook (7^th Edition):

Hidayah, Lailatul. “VarB Plus: An Integrated Tool for Visualization of Genome Variation Datasets.” 2012. Web. 12 Apr 2021.

Vancouver:

Hidayah L. VarB Plus: An Integrated Tool for Visualization of Genome Variation Datasets. [Internet] [Thesis]. King Abdullah University of Science and Technology; 2012. [cited 2021 Apr 12]. Available from: http://hdl.handle.net/10754/244612.

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

Council of Science Editors:

Hidayah L. VarB Plus: An Integrated Tool for Visualization of Genome Variation Datasets. [Thesis]. King Abdullah University of Science and Technology; 2012. Available from: http://hdl.handle.net/10754/244612

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

King Abdullah University of Science and Technology

4. Danani, Bob K. Development of a Computational Steering Framework for High Performance Computing Environments on Blue Gene/P Systems.

Degree: Computer, Electrical and Mathematical Sciences and Engineering (CEMSE) Division, 2012, King Abdullah University of Science and Technology

URL: http://hdl.handle.net/10754/267252

► Computational steering has revolutionized the traditional workflow in high performance computing (HPC) applications. The standard workflow that consists of preparation of an application’s input, running… (more)

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APA (6^th Edition):

Danani, B. K. (2012). Development of a Computational Steering Framework for High Performance Computing Environments on Blue Gene/P Systems. (Thesis). King Abdullah University of Science and Technology. Retrieved from http://hdl.handle.net/10754/267252

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):

Danani, Bob K. “Development of a Computational Steering Framework for High Performance Computing Environments on Blue Gene/P Systems.” 2012. Thesis, King Abdullah University of Science and Technology. Accessed April 12, 2021. http://hdl.handle.net/10754/267252.

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

MLA Handbook (7^th Edition):

Danani, Bob K. “Development of a Computational Steering Framework for High Performance Computing Environments on Blue Gene/P Systems.” 2012. Web. 12 Apr 2021.

Vancouver:

Danani BK. Development of a Computational Steering Framework for High Performance Computing Environments on Blue Gene/P Systems. [Internet] [Thesis]. King Abdullah University of Science and Technology; 2012. [cited 2021 Apr 12]. Available from: http://hdl.handle.net/10754/267252.

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

Council of Science Editors:

Danani BK. Development of a Computational Steering Framework for High Performance Computing Environments on Blue Gene/P Systems. [Thesis]. King Abdullah University of Science and Technology; 2012. Available from: http://hdl.handle.net/10754/267252

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

King Abdullah University of Science and Technology

5. Ibeid, Huda. Modeling the Performance of Fast Mulipole Method on HPC platforms.

Degree: Computer, Electrical and Mathematical Sciences and Engineering (CEMSE) Division, 2012, King Abdullah University of Science and Technology

URL: http://hdl.handle.net/10754/267452

► The current trend in high performance computing is pushing towards exascale computing. To achieve this exascale performance, future systems will have between 100 million and… (more)

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

APA (6^th Edition):

Ibeid, H. (2012). Modeling the Performance of Fast Mulipole Method on HPC platforms. (Thesis). King Abdullah University of Science and Technology. Retrieved from http://hdl.handle.net/10754/267452

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):

Ibeid, Huda. “Modeling the Performance of Fast Mulipole Method on HPC platforms.” 2012. Thesis, King Abdullah University of Science and Technology. Accessed April 12, 2021. http://hdl.handle.net/10754/267452.

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

MLA Handbook (7^th Edition):

Ibeid, Huda. “Modeling the Performance of Fast Mulipole Method on HPC platforms.” 2012. Web. 12 Apr 2021.

Vancouver:

Ibeid H. Modeling the Performance of Fast Mulipole Method on HPC platforms. [Internet] [Thesis]. King Abdullah University of Science and Technology; 2012. [cited 2021 Apr 12]. Available from: http://hdl.handle.net/10754/267452.

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

Council of Science Editors:

Ibeid H. Modeling the Performance of Fast Mulipole Method on HPC platforms. [Thesis]. King Abdullah University of Science and Technology; 2012. Available from: http://hdl.handle.net/10754/267452

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

King Abdullah University of Science and Technology

6. Amir, Sahar. Accelerating Monte Carlo Molecular Simulations Using Novel Extrapolation Schemes Combined with Fast Database Generation on Massively Parallel Machines.

Degree: Computer, Electrical and Mathematical Sciences and Engineering (CEMSE) Division, 2013, King Abdullah University of Science and Technology

URL: http://hdl.handle.net/10754/292974

► We introduce an efficient thermodynamically consistent technique to extrapolate and interpolate normalized Canonical NVT ensemble averages like pressure and energy for Lennard-Jones (L-J) fluids. Preliminary… (more)

▼ We introduce an efficient thermodynamically consistent technique to extrapolate and interpolate normalized Canonical NVT ensemble averages like pressure and energy for Lennard-Jones (L-J) fluids. Preliminary results show promising applicability in oil and gas modeling, where accurate determination of thermodynamic properties in reservoirs is challenging. The thermodynamic interpolation and thermodynamic extrapolation schemes predict ensemble averages at different thermodynamic conditions from expensively simulated data points. The methods reweight and reconstruct previously generated database values of Markov chains at neighboring temperature and density conditions. To investigate the efficiency of these methods, two databases corresponding to different combinations of normalized density and temperature are generated. One contains 175 Markov chains with 10,000,000 MC cycles each and the other contains 3000 Markov chains with 61,000,000 MC cycles each. For such massive database creation, two algorithms to parallelize the computations have been investigated. The accuracy of the thermodynamic extrapolation scheme is investigated with respect to classical interpolation and extrapolation. Finally, thermodynamic interpolation benefiting from four neighboring Markov chains points is implemented and compared with previous schemes. The thermodynamic interpolation scheme using knowledge from the four neighboring points proves to be more accurate than the thermodynamic extrapolation from the closest point only, while both thermodynamic extrapolation and thermodynamic interpolation are more accurate than the classical interpolation and extrapolation. The investigated extrapolation scheme has great potential in oil and gas reservoir modeling.That is, such a scheme has the potential to speed up the MCMC thermodynamic computation to be comparable with conventional Equation of State approaches in efficiency. In particular, this makes it applicable to large-scale optimization of L-J model parameters for hydrocarbons and other important reservoir species. The efficiency of the thermodynamic dependent techniques is expected to make the Markov chains simulation an attractive alternative in compositional multiphase flow simulation. Advisors/Committee Members: Keyes, David E. (advisor), Moshkov, Mikhail (committee member), Sun, Shuyu (committee member).

Subjects/Keywords: molecular Simulation; Monte Carlo; Lenward-Jones Fluid; Interpolation; extrapolation; canonical ensemble

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APA (6^th Edition):

Amir, S. (2013). Accelerating Monte Carlo Molecular Simulations Using Novel Extrapolation Schemes Combined with Fast Database Generation on Massively Parallel Machines. (Thesis). King Abdullah University of Science and Technology. Retrieved from http://hdl.handle.net/10754/292974

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):

Amir, Sahar. “Accelerating Monte Carlo Molecular Simulations Using Novel Extrapolation Schemes Combined with Fast Database Generation on Massively Parallel Machines.” 2013. Thesis, King Abdullah University of Science and Technology. Accessed April 12, 2021. http://hdl.handle.net/10754/292974.

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

MLA Handbook (7^th Edition):

Amir, Sahar. “Accelerating Monte Carlo Molecular Simulations Using Novel Extrapolation Schemes Combined with Fast Database Generation on Massively Parallel Machines.” 2013. Web. 12 Apr 2021.

Vancouver:

Amir S. Accelerating Monte Carlo Molecular Simulations Using Novel Extrapolation Schemes Combined with Fast Database Generation on Massively Parallel Machines. [Internet] [Thesis]. King Abdullah University of Science and Technology; 2013. [cited 2021 Apr 12]. Available from: http://hdl.handle.net/10754/292974.

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

Council of Science Editors:

Amir S. Accelerating Monte Carlo Molecular Simulations Using Novel Extrapolation Schemes Combined with Fast Database Generation on Massively Parallel Machines. [Thesis]. King Abdullah University of Science and Technology; 2013. Available from: http://hdl.handle.net/10754/292974

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

King Abdullah University of Science and Technology

7. Xiao, Bingmu. Focusing of Acoustic Waves through Acoustic Materials with Subwavelength Structures.

Degree: Physical Science and Engineering (PSE) Division, 2013, King Abdullah University of Science and Technology

URL: http://hdl.handle.net/10754/294181

► In this thesis, wave propagation through acoustic materials with subwavelength slits structures is studied. Guided by the findings, acoustic wave focusing is achieved with a… (more)

Subjects/Keywords: Acoustic Focusing; Effective Medium Theory; Sub wave length

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APA (6^th Edition):

Xiao, B. (2013). Focusing of Acoustic Waves through Acoustic Materials with Subwavelength Structures. (Thesis). King Abdullah University of Science and Technology. Retrieved from http://hdl.handle.net/10754/294181

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):

Xiao, Bingmu. “Focusing of Acoustic Waves through Acoustic Materials with Subwavelength Structures.” 2013. Thesis, King Abdullah University of Science and Technology. Accessed April 12, 2021. http://hdl.handle.net/10754/294181.

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

MLA Handbook (7^th Edition):

Xiao, Bingmu. “Focusing of Acoustic Waves through Acoustic Materials with Subwavelength Structures.” 2013. Web. 12 Apr 2021.

Vancouver:

Xiao B. Focusing of Acoustic Waves through Acoustic Materials with Subwavelength Structures. [Internet] [Thesis]. King Abdullah University of Science and Technology; 2013. [cited 2021 Apr 12]. Available from: http://hdl.handle.net/10754/294181.

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

Council of Science Editors:

Xiao B. Focusing of Acoustic Waves through Acoustic Materials with Subwavelength Structures. [Thesis]. King Abdullah University of Science and Technology; 2013. Available from: http://hdl.handle.net/10754/294181

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

King Abdullah University of Science and Technology

8. Larisch, Lukas. Three-dimensional Modeling and Simulation of a Tuning Fork.

Degree: Computer, Electrical and Mathematical Sciences and Engineering (CEMSE) Division, 2018, King Abdullah University of Science and Technology

URL: http://hdl.handle.net/10754/628716

► The mathematical characterization of the sound of a musical instrument still follows Schumann’s laws [1]. According to this theory, the resonances of the instrument body,… (more)

Subjects/Keywords: tuning fork; linear elasticity; FEM; Solid mechanics; experimental model analysis; PINVIT

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APA (6^th Edition):

Larisch, L. (2018). Three-dimensional Modeling and Simulation of a Tuning Fork. (Thesis). King Abdullah University of Science and Technology. Retrieved from http://hdl.handle.net/10754/628716

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):

Larisch, Lukas. “Three-dimensional Modeling and Simulation of a Tuning Fork.” 2018. Thesis, King Abdullah University of Science and Technology. Accessed April 12, 2021. http://hdl.handle.net/10754/628716.

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

MLA Handbook (7^th Edition):

Larisch, Lukas. “Three-dimensional Modeling and Simulation of a Tuning Fork.” 2018. Web. 12 Apr 2021.

Vancouver:

Larisch L. Three-dimensional Modeling and Simulation of a Tuning Fork. [Internet] [Thesis]. King Abdullah University of Science and Technology; 2018. [cited 2021 Apr 12]. Available from: http://hdl.handle.net/10754/628716.

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

Council of Science Editors:

Larisch L. Three-dimensional Modeling and Simulation of a Tuning Fork. [Thesis]. King Abdullah University of Science and Technology; 2018. Available from: http://hdl.handle.net/10754/628716

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

King Abdullah University of Science and Technology

9. Alharthi, Noha. Fast High-order Integral Equation Solvers for Acoustic and Electromagnetic Scattering Problems.

Degree: Computer, Electrical and Mathematical Sciences and Engineering (CEMSE) Division, 2019, King Abdullah University of Science and Technology

URL: http://hdl.handle.net/10754/660105

► Acoustic and electromagnetic scattering from arbitrarily shaped structures can be numerically characterized by solving various surface integral equations (SIEs). One of the most effective techniques… (more)

▼ Acoustic and electromagnetic scattering from arbitrarily shaped structures can be numerically characterized by solving various surface integral equations (SIEs). One of the most effective techniques to solve SIEs is the Nyström method. Compared to other existing methods,the Nyström method is easier to implement especially when the geometrical discretization is non-conforming and higher-order representations of the geometry and unknowns are desired. However,singularities of the Green’s function are more difﬁcult to”manage”since they are not ”smoothened” through the use of a testing function. This dissertation describes purely numerical schemes to account for different orders of singularities that appear in acoustic and electromagnetic SIEs when they are solved by a high-order Nyström method utilizing a mesh of curved discretization elements. These schemes make use of two sets of basis functions to smoothen singular integrals: the grid robust high-order Lagrange and the high-order Silvester-Lagrange interpolation basis functions. Numerical results comparing the convergence of two schemes are presented. Moreover, an extremely scalable implementation of fast multipole method (FMM) is developed to efﬁciently (and iteratively) solve the linear system resulting from the discretization of the acoustic SIEs by the Nyström method. The implementation results in O(N log N) complexity for high-frequency scattering problems. This FMM-accelerated solver can handle N =2 billion on a 200,000-core Cray XC40 with 85% strong scaling efﬁciency. Iterative solvers are often ineffective for ill-conditioned problems. Thus, a fast direct (LU)solver,which makes use of low-rank matrix approximations,is also developed. This solver relies on tile low rank (TLR) data compression format, as implemented in the hierarchical computations on many corearchitectures (HiCMA) library. This requires to taskify the underlying SIE kernels to expose ﬁne-grained computations. The resulting asynchronous execution permit to weaken the artifactual synchronization points,while mitigating the overhead of data motion. We compare the obtained performance results of our TLRLU factorization against the state-of-the-art dense factorizations on shared memory systems. We achieve up to a fourfold performance speedup on a 3D acoustic problem with up to 150 K unknowns in double complex precision arithmetics. Advisors/Committee Members: Keyes, David E. (advisor), Hadwiger, Markus (committee member), Bagci, Hakan (committee member), Kressner, Daniel (committee member).

Subjects/Keywords: Boundary Integral Equation; Acoustic Scattering; LU-Based Solver; Fast Solvers; Fast Multipole Solvers; Tile Low-Rank Approximations

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APA (6^th Edition):

Alharthi, N. (2019). Fast High-order Integral Equation Solvers for Acoustic and Electromagnetic Scattering Problems. (Thesis). King Abdullah University of Science and Technology. Retrieved from http://hdl.handle.net/10754/660105

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):

Alharthi, Noha. “Fast High-order Integral Equation Solvers for Acoustic and Electromagnetic Scattering Problems.” 2019. Thesis, King Abdullah University of Science and Technology. Accessed April 12, 2021. http://hdl.handle.net/10754/660105.

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

MLA Handbook (7^th Edition):

Alharthi, Noha. “Fast High-order Integral Equation Solvers for Acoustic and Electromagnetic Scattering Problems.” 2019. Web. 12 Apr 2021.

Vancouver:

Alharthi N. Fast High-order Integral Equation Solvers for Acoustic and Electromagnetic Scattering Problems. [Internet] [Thesis]. King Abdullah University of Science and Technology; 2019. [cited 2021 Apr 12]. Available from: http://hdl.handle.net/10754/660105.

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

Council of Science Editors:

Alharthi N. Fast High-order Integral Equation Solvers for Acoustic and Electromagnetic Scattering Problems. [Thesis]. King Abdullah University of Science and Technology; 2019. Available from: http://hdl.handle.net/10754/660105

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

King Abdullah University of Science and Technology

10. Silva, Mickael Messias. A Numerical Investigation of Pre-chamber Combustion Engines.

Degree: Physical Science and Engineering (PSE) Division, 2020, King Abdullah University of Science and Technology

URL: http://hdl.handle.net/10754/664493

► This work aims to enhance fundamental and practical understanding of pre-chamber (PC) combustion engines, using computational fluid dynamics (CFD) simulations conducted with the software CONVERGE… (more)

▼ This work aims to enhance fundamental and practical understanding of pre-chamber (PC) combustion engines, using computational fluid dynamics (CFD) simulations conducted with the software CONVERGE employing the Reynolds-averaged Navier-Stokes turbulence closure and the well-stirred reactor combustion model for methane oxidation. First, to help the design of the KAUST pre-chamber, the simulations were conducted to assess the impact of design parameters such as throat and nozzle diameters, and nozzle length in a passively operated pre-chamber at lean conditions. The geometrical parameters showed to affect the pre-chamber combustion characteristics, such as pressure build-up, radical formation, heat release, and the composition of the jets penetrating and igniting the main chamber charge. It was found that the narrow-throat pre-chamber is strongly influenced by the throat diameter, but weakly influenced by nozzle length. A flow reversal pattern was observed, promoting the accumulation of intermediate species in the PC, leading to a secondary heat release. Subsequently, the validation of the actively fueled pre-chamber systems was assessed under different fueling strategy and validated against experimental data. The last chapter analyzes the impact of enrichment and stratification of the pre-chamber on the main chamber combustion. An open-cycle simulation was conducted to describe the full interaction between both chambers. The influence of fuel enrichment in the PC was compared to the passive mode operation and found to greatly impact in the overall system performance. It was found that the excessively rich PC does not yield the optimal results; instead, a pre-chamber with stoichiometric composition at spark timing does. Although the fuel distribution inside the PC 5 was not homogeneous, the active control of the PC was shown to enable a command of the pressure response. It was found that the upstream flame propagation forces part of the PC mixture to leak to the main chamber, creating localized fuel rich regions, which enhances the combustion of the MC charge. The overall MC combustion is found to be complex, influenced by the turbulent mixing and local cooling, and possibly local quenching events. The detailed interaction of mixing and combustion in the MC is not fully understood and is subject of future studies. Advisors/Committee Members: Im, Hong G. (advisor), Bengt, Johansson (committee member), Keyes, David E. (committee member).

Subjects/Keywords: Clean combustion; Engines; Computational fluid dynamics; Pre-chamber; Large scale simulation

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APA (6^th Edition):

Silva, M. M. (2020). A Numerical Investigation of Pre-chamber Combustion Engines. (Thesis). King Abdullah University of Science and Technology. Retrieved from http://hdl.handle.net/10754/664493

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):

Silva, Mickael Messias. “A Numerical Investigation of Pre-chamber Combustion Engines.” 2020. Thesis, King Abdullah University of Science and Technology. Accessed April 12, 2021. http://hdl.handle.net/10754/664493.

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

MLA Handbook (7^th Edition):

Silva, Mickael Messias. “A Numerical Investigation of Pre-chamber Combustion Engines.” 2020. Web. 12 Apr 2021.

Vancouver:

Silva MM. A Numerical Investigation of Pre-chamber Combustion Engines. [Internet] [Thesis]. King Abdullah University of Science and Technology; 2020. [cited 2021 Apr 12]. Available from: http://hdl.handle.net/10754/664493.

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

Council of Science Editors:

Silva MM. A Numerical Investigation of Pre-chamber Combustion Engines. [Thesis]. King Abdullah University of Science and Technology; 2020. Available from: http://hdl.handle.net/10754/664493

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

King Abdullah University of Science and Technology

11. Briantceva, Nadezhda. Fundamental Molecular Communication Modelling.

Degree: Computer, Electrical and Mathematical Sciences and Engineering (CEMSE) Division, 2020, King Abdullah University of Science and Technology

URL: http://hdl.handle.net/10754/664850

► As traditional communication technology we use in our day-to-day life reaches its limitations, the international community searches for new methods to communicate information. One such… (more)

Subjects/Keywords: Molecular communication; Finite difference scheme; Discontinuous Galerkin; Channel modelling

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APA (6^th Edition):

Briantceva, N. (2020). Fundamental Molecular Communication Modelling. (Thesis). King Abdullah University of Science and Technology. Retrieved from http://hdl.handle.net/10754/664850

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):

Briantceva, Nadezhda. “Fundamental Molecular Communication Modelling.” 2020. Thesis, King Abdullah University of Science and Technology. Accessed April 12, 2021. http://hdl.handle.net/10754/664850.

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

MLA Handbook (7^th Edition):

Briantceva, Nadezhda. “Fundamental Molecular Communication Modelling.” 2020. Web. 12 Apr 2021.

Vancouver:

Briantceva N. Fundamental Molecular Communication Modelling. [Internet] [Thesis]. King Abdullah University of Science and Technology; 2020. [cited 2021 Apr 12]. Available from: http://hdl.handle.net/10754/664850.

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

Council of Science Editors:

Briantceva N. Fundamental Molecular Communication Modelling. [Thesis]. King Abdullah University of Science and Technology; 2020. Available from: http://hdl.handle.net/10754/664850

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

King Abdullah University of Science and Technology

12. Mankowski, Michal. Dynamic Programming Multi-Objective Combinatorial Optimization.

Degree: Computer, Electrical and Mathematical Sciences and Engineering (CEMSE) Division, 2020, King Abdullah University of Science and Technology

URL: http://hdl.handle.net/10754/665627

► In this dissertation, we consider extensions of dynamic programming for combinatorial optimization. We introduce two exact multi-objective optimization algorithms: the multi-stage optimization algorithm that optimizes… (more)

▼ In this dissertation, we consider extensions of dynamic programming for combinatorial optimization. We introduce two exact multi-objective optimization algorithms: the multi-stage optimization algorithm that optimizes the problem relative to the ordered sequence of objectives (lexicographic optimization) and the bi-criteria optimization algorithm that simultaneously optimizes the problem relative to two objectives (Pareto optimization). We also introduce a counting algorithm to count optimal solution before and after every optimization stage of multi-stage optimization. We propose a fairly universal approach based on so-called circuits without repetitions in which each element is generated exactly one time. Such circuits represent the sets of elements under consideration (the sets of feasible solutions) and are used by counting, multi-stage, and bi-criteria optimization algorithms. For a given optimization problem, we should describe an appropriate circuit and cost functions. Then, we can use the designed algorithms for which we already have proofs of their correctness and ways to evaluate the required number of operations and the time. We construct conventional (which work directly with elements) circuits without repetitions for matrix chain multiplication, global sequence alignment, optimal paths in directed graphs, binary search trees, convex polygon triangulation, line breaking (text justification), one-dimensional clustering, optimal bitonic tour, and segmented least squares. For these problems, we evaluate the number of operations and the time required by the optimization and counting algorithms, and consider the results of computational experiments. If we cannot find a conventional circuit without repetitions for a problem, we can either create custom algorithms for optimization and counting from scratch or can transform a circuit with repetitions into a so-called syntactical circuit, which is a circuit without repetitions that works not with elements but with formulas representing these elements. We apply both approaches to the optimization of matchings in trees and apply the second approach to the 0/1 knapsack problem. We also briefly introduce our work in operation research with applications to health care. This work extends our interest in the optimization field from developing new methods included in this dissertation towards the practical application. Advisors/Committee Members: Moshkov, Mikhail (advisor), Keyes, David E. (committee member), Shihada, Basem (committee member), Boros, Endre (committee member).

Subjects/Keywords: Dynamic Programming; Combinatorial Optimization; Multi-Objective Optimization

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APA (6^th Edition):

Mankowski, M. (2020). Dynamic Programming Multi-Objective Combinatorial Optimization. (Thesis). King Abdullah University of Science and Technology. Retrieved from http://hdl.handle.net/10754/665627

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):

Mankowski, Michal. “Dynamic Programming Multi-Objective Combinatorial Optimization.” 2020. Thesis, King Abdullah University of Science and Technology. Accessed April 12, 2021. http://hdl.handle.net/10754/665627.

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

MLA Handbook (7^th Edition):

Mankowski, Michal. “Dynamic Programming Multi-Objective Combinatorial Optimization.” 2020. Web. 12 Apr 2021.

Vancouver:

Mankowski M. Dynamic Programming Multi-Objective Combinatorial Optimization. [Internet] [Thesis]. King Abdullah University of Science and Technology; 2020. [cited 2021 Apr 12]. Available from: http://hdl.handle.net/10754/665627.

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

Council of Science Editors:

Mankowski M. Dynamic Programming Multi-Objective Combinatorial Optimization. [Thesis]. King Abdullah University of Science and Technology; 2020. Available from: http://hdl.handle.net/10754/665627

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

King Abdullah University of Science and Technology

13. Alnasser, Ali. An Empirical Study of the Distributed Ellipsoidal Trust Region Method for Large Batch Training.

Degree: Computer, Electrical and Mathematical Sciences and Engineering (CEMSE) Division, 2021, King Abdullah University of Science and Technology

URL: http://hdl.handle.net/10754/667327

► Neural networks optimizers are dominated by rst-order methods, due to their inexpensive computational cost per iteration. However, it has been shown that rstorder optimization is… (more)

Subjects/Keywords: optimization; trust region; distributed computing; deep learning; machine learning

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APA (6^th Edition):

Alnasser, A. (2021). An Empirical Study of the Distributed Ellipsoidal Trust Region Method for Large Batch Training. (Thesis). King Abdullah University of Science and Technology. Retrieved from http://hdl.handle.net/10754/667327

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):

Alnasser, Ali. “An Empirical Study of the Distributed Ellipsoidal Trust Region Method for Large Batch Training.” 2021. Thesis, King Abdullah University of Science and Technology. Accessed April 12, 2021. http://hdl.handle.net/10754/667327.

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

MLA Handbook (7^th Edition):

Alnasser, Ali. “An Empirical Study of the Distributed Ellipsoidal Trust Region Method for Large Batch Training.” 2021. Web. 12 Apr 2021.

Vancouver:

Alnasser A. An Empirical Study of the Distributed Ellipsoidal Trust Region Method for Large Batch Training. [Internet] [Thesis]. King Abdullah University of Science and Technology; 2021. [cited 2021 Apr 12]. Available from: http://hdl.handle.net/10754/667327.

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

Council of Science Editors:

Alnasser A. An Empirical Study of the Distributed Ellipsoidal Trust Region Method for Large Batch Training. [Thesis]. King Abdullah University of Science and Technology; 2021. Available from: http://hdl.handle.net/10754/667327

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

King Abdullah University of Science and Technology

14. Babayev, Rafig. Hydrogen Combustion versus Diesel Isobaric Combustion in the Double Compression-Expansion Engine.

Degree: Physical Sciences and Engineering (PSE) Division, 2020, King Abdullah University of Science and Technology

URL: http://hdl.handle.net/10754/667503

► This thesis aims to contribute to the research and development of a new highly efficient split-cycle engine concept – the double compression-expansion engine (DCEE) –… (more)

▼ This thesis aims to contribute to the research and development of a new highly efficient split-cycle engine concept – the double compression-expansion engine (DCEE) – by expanding the knowledge of combustion processes suitable for this and, potentially, other modern engines, via experimental and computational studies. In this work, first, the importance of continued improvement of internal combustion engines is demonstrated by comparing the life-cycle CO2 emissions of different modes of transport, including walking and bicycling. Then, an isobaric combustion concept is proposed for use in modern high-pressure combustion engines, such as the DCEE. Isobaric combustion is compared to conventional diesel combustion at different pressure levels, fueling, and EGR rates, and shown to reduce cylinder wall heat transfer losses by 20 %, simultaneously improving the NOx emissions by a factor of two. An in-situ injection rate measurement technique is developed and applied to improve the understanding of the complex injection strategies required for isobaric combustion. It is also shown that isobaric combustion is possible to achieve with a single fuel injector, but using multiple injectors may offer additional benefits of even lower heat losses, better heat release control, and improved soot and NOx trade-off. Then, an alternative combustion system to the diesel isobaric is proposed – a hydrogen direct-injection (DI) compression-ignition (CI) combustion concept, which has the advantage of ideally eliminated CO2 and soot emissions. DICI H2 combustion is found to differ significantly from conventional diesel, most importantly, in terms of the injected and retained momentum, and in-cylinder flow patterns and fuel-air mixing. Thus, a completely different optimization path must be taken for H2 engines, which involves maximizing the free-jet mixing phase of combustion while minimizing the momentum-dominated global mixing phase. This is achieved computationally in this work by adapting the combustion chamber shape to the H2 jets and modifying the injector nozzle, which proved effective. Finally, hydrogen combustion is computationally compared to diesel in the context of the DCEE on the basis of thermodynamic system parameters and detailed energy breakdown, and proved superior. Brake thermal efficiencies in the range of 56 % are demonstrated for the entire DCEE powertrain fueled with hydrogen. Advisors/Committee Members: Johansson, Bengt (advisor), Im, Hong (committee member), Keyes, David E. (committee member), Taylor, Alex (committee member).

Subjects/Keywords: isobaric combustion; hydrogen combustion; multiple fuel injectors; DCEE; hydrogen engine; CFD

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APA (6^th Edition):

Babayev, R. (2020). Hydrogen Combustion versus Diesel Isobaric Combustion in the Double Compression-Expansion Engine. (Thesis). King Abdullah University of Science and Technology. Retrieved from http://hdl.handle.net/10754/667503

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):

Babayev, Rafig. “Hydrogen Combustion versus Diesel Isobaric Combustion in the Double Compression-Expansion Engine.” 2020. Thesis, King Abdullah University of Science and Technology. Accessed April 12, 2021. http://hdl.handle.net/10754/667503.

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

MLA Handbook (7^th Edition):

Babayev, Rafig. “Hydrogen Combustion versus Diesel Isobaric Combustion in the Double Compression-Expansion Engine.” 2020. Web. 12 Apr 2021.

Vancouver:

Babayev R. Hydrogen Combustion versus Diesel Isobaric Combustion in the Double Compression-Expansion Engine. [Internet] [Thesis]. King Abdullah University of Science and Technology; 2020. [cited 2021 Apr 12]. Available from: http://hdl.handle.net/10754/667503.

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

Council of Science Editors:

Babayev R. Hydrogen Combustion versus Diesel Isobaric Combustion in the Double Compression-Expansion Engine. [Thesis]. King Abdullah University of Science and Technology; 2020. Available from: http://hdl.handle.net/10754/667503

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

King Abdullah University of Science and Technology

15. Haji Ali, Abdul Lateef. Pedestrian Flow in the Mean Field Limit.

Degree: Computer, Electrical and Mathematical Sciences and Engineering (CEMSE) Division, 2012, King Abdullah University of Science and Technology

URL: http://hdl.handle.net/10754/250912

► We study the mean-field limit of a particle-based system modeling the behavior of many indistinguishable pedestrians as their number increases. The base model is a… (more)

Subjects/Keywords: Crowd modeling; Mean-Field; Helbing; Pedestrian; Particle MLMC

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APA (6^th Edition):

Haji Ali, A. L. (2012). Pedestrian Flow in the Mean Field Limit. (Thesis). King Abdullah University of Science and Technology. Retrieved from http://hdl.handle.net/10754/250912

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):

Haji Ali, Abdul Lateef. “Pedestrian Flow in the Mean Field Limit.” 2012. Thesis, King Abdullah University of Science and Technology. Accessed April 12, 2021. http://hdl.handle.net/10754/250912.

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

MLA Handbook (7^th Edition):

Haji Ali, Abdul Lateef. “Pedestrian Flow in the Mean Field Limit.” 2012. Web. 12 Apr 2021.

Vancouver:

Haji Ali AL. Pedestrian Flow in the Mean Field Limit. [Internet] [Thesis]. King Abdullah University of Science and Technology; 2012. [cited 2021 Apr 12]. Available from: http://hdl.handle.net/10754/250912.

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

Council of Science Editors:

Haji Ali AL. Pedestrian Flow in the Mean Field Limit. [Thesis]. King Abdullah University of Science and Technology; 2012. Available from: http://hdl.handle.net/10754/250912

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

King Abdullah University of Science and Technology

16. Abdulwahed, Naif B. CHAOS-BASED ADVANCED ENCRYPTION STANDARD.

Degree: Computer, Electrical and Mathematical Sciences and Engineering (CEMSE) Division, 2013, King Abdullah University of Science and Technology

URL: http://hdl.handle.net/10754/292821

► This thesis introduces a new chaos-based Advanced Encryption Standard (AES). The AES is a well-known encryption algorithm that was standardized by U.S National Institute of… (more)

▼ This thesis introduces a new chaos-based Advanced Encryption Standard (AES). The AES is a well-known encryption algorithm that was standardized by U.S National Institute of Standard and Technology (NIST) in 2001. The thesis investigates and explores the behavior of the AES algorithm by replacing two of its original modules, namely the S-Box and the Key Schedule, with two other chaos- based modules. Three chaos systems are considered in designing the new modules which are Lorenz system with multiplication nonlinearity, Chen system with sign modules nonlinearity, and 1D multiscroll system with stair case nonlinearity. The three systems are evaluated on their sensitivity to initial conditions and as Pseudo Random Number Generators (PRNG) after applying a post-processing technique to their output then performing NIST SP. 800-22 statistical tests. The thesis presents a hardware implementation of dynamic S-Boxes for AES that are populated using the three chaos systems. Moreover, a full MATLAB package to analyze the chaos generated S-Boxes based on graphical analysis, Walsh-Hadamard spectrum analysis, and image encryption analysis is developed. Although these S-Boxes are dynamic, meaning they are regenerated whenever the encryption key is changed, the analysis results show that such S-Boxes exhibit good properties like the Strict Avalanche Criterion (SAC) and the nonlinearity and in the application of image encryption. Furthermore, the thesis presents a new Lorenz-chaos-based key expansion for the AES. Many researchers have pointed out that there are some defects in the original key expansion of AES and thus have motivated such chaos-based key expansion proposal. The new proposed key schedule is analyzed and assessed in terms of confusion and diffusion by performing the frequency and SAC test respectively. The obtained results show that the new proposed design is more secure than the original AES key schedule and other proposed designs in the literature. The proposed design is then enhanced to increase the operating speed using the divide- and-conquer concept. Such enhancement, did not only make the AES algorithm more secure, but also enabled the AES to be faster, as it can now operate on higher frequencies, and more area-efficient. Advisors/Committee Members: Keyes, David E. (advisor), Alouini, Mohamed-Slim (committee member), Fahmy, Hossam A.H. (committee member), Salama, Khaled N. (committee member).

Subjects/Keywords: AES; Chaos; PRNG; Encryption; Key-schedule; S-Box

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APA (6^th Edition):

Abdulwahed, N. B. (2013). CHAOS-BASED ADVANCED ENCRYPTION STANDARD. (Thesis). King Abdullah University of Science and Technology. Retrieved from http://hdl.handle.net/10754/292821

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):

Abdulwahed, Naif B. “CHAOS-BASED ADVANCED ENCRYPTION STANDARD.” 2013. Thesis, King Abdullah University of Science and Technology. Accessed April 12, 2021. http://hdl.handle.net/10754/292821.

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

MLA Handbook (7^th Edition):

Abdulwahed, Naif B. “CHAOS-BASED ADVANCED ENCRYPTION STANDARD.” 2013. Web. 12 Apr 2021.

Vancouver:

Abdulwahed NB. CHAOS-BASED ADVANCED ENCRYPTION STANDARD. [Internet] [Thesis]. King Abdullah University of Science and Technology; 2013. [cited 2021 Apr 12]. Available from: http://hdl.handle.net/10754/292821.

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

Council of Science Editors:

Abdulwahed NB. CHAOS-BASED ADVANCED ENCRYPTION STANDARD. [Thesis]. King Abdullah University of Science and Technology; 2013. Available from: http://hdl.handle.net/10754/292821

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

King Abdullah University of Science and Technology

17. Scott, Anna A. The Intertropical Convergence Zone over the Middle East and North Africa: Detection and Trends.

Degree: Computer, Electrical and Mathematical Sciences and Engineering (CEMSE) Division, 2013, King Abdullah University of Science and Technology

URL: http://hdl.handle.net/10754/293680

► This thesis provides an overview of identifying the Intertropical Convergence Zone (ITCZ) in the Middle East and North Africa (MENA) region. The ITCZ is a… (more)

Subjects/Keywords: ITCZ; CLIMATE; AFRICA; PRECIPITATION; CONVERGENCE

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APA (6^th Edition):

Scott, A. A. (2013). The Intertropical Convergence Zone over the Middle East and North Africa: Detection and Trends. (Thesis). King Abdullah University of Science and Technology. Retrieved from http://hdl.handle.net/10754/293680

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):

Scott, Anna A. “The Intertropical Convergence Zone over the Middle East and North Africa: Detection and Trends.” 2013. Thesis, King Abdullah University of Science and Technology. Accessed April 12, 2021. http://hdl.handle.net/10754/293680.

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

MLA Handbook (7^th Edition):

Scott, Anna A. “The Intertropical Convergence Zone over the Middle East and North Africa: Detection and Trends.” 2013. Web. 12 Apr 2021.

Vancouver:

Scott AA. The Intertropical Convergence Zone over the Middle East and North Africa: Detection and Trends. [Internet] [Thesis]. King Abdullah University of Science and Technology; 2013. [cited 2021 Apr 12]. Available from: http://hdl.handle.net/10754/293680.

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

Council of Science Editors:

Scott AA. The Intertropical Convergence Zone over the Middle East and North Africa: Detection and Trends. [Thesis]. King Abdullah University of Science and Technology; 2013. Available from: http://hdl.handle.net/10754/293680

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

King Abdullah University of Science and Technology

18. Faria, Luiz. Qualitative and Asymptotic Theory of Detonations.

Degree: Computer, Electrical and Mathematical Sciences and Engineering (CEMSE) Division, 2014, King Abdullah University of Science and Technology

URL: http://hdl.handle.net/10754/335798

► Shock waves in reactive media possess very rich dynamics: from formation of cells in multiple dimensions to oscillating shock fronts in one-dimension. Because of the… (more)

Subjects/Keywords: detonation; Stability; chaos; shock waves; asymptotics

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APA (6^th Edition):

Faria, L. (2014). Qualitative and Asymptotic Theory of Detonations. (Thesis). King Abdullah University of Science and Technology. Retrieved from http://hdl.handle.net/10754/335798

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):

Faria, Luiz. “Qualitative and Asymptotic Theory of Detonations.” 2014. Thesis, King Abdullah University of Science and Technology. Accessed April 12, 2021. http://hdl.handle.net/10754/335798.

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

MLA Handbook (7^th Edition):

Faria, Luiz. “Qualitative and Asymptotic Theory of Detonations.” 2014. Web. 12 Apr 2021.

Vancouver:

Faria L. Qualitative and Asymptotic Theory of Detonations. [Internet] [Thesis]. King Abdullah University of Science and Technology; 2014. [cited 2021 Apr 12]. Available from: http://hdl.handle.net/10754/335798.

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

Council of Science Editors:

Faria L. Qualitative and Asymptotic Theory of Detonations. [Thesis]. King Abdullah University of Science and Technology; 2014. Available from: http://hdl.handle.net/10754/335798

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

19. Vilanova, Pedro. Multilevel Approximations of Markovian Jump Processes with Applications in Communication Networks.

Degree: Computer, Electrical and Mathematical Sciences and Engineering (CEMSE) Division, 2015, King Abdullah University of Science and Technology

URL: http://hdl.handle.net/10754/552664

► This thesis focuses on the development and analysis of efficient simulation and inference techniques for Markovian pure jump processes with a view towards applications in… (more)

▼ This thesis focuses on the development and analysis of efficient simulation and inference techniques for Markovian pure jump processes with a view towards applications in dense communication networks. These techniques are especially relevant for modeling networks of smart devices —tiny, abundant microprocessors with integrated sensors and wireless communication abilities— that form highly complex and diverse communication networks. During 2010, the number of devices connected to the Internet exceeded the number of people on Earth: over 12.5 billion devices. By 2015, Cisco’s Internet Business Solutions Group predicts that this number will exceed 25 billion. The first part of this work proposes novel numerical methods to estimate, in an efficient and accurate way, observables from realizations of Markovian jump processes. In particular, hybrid Monte Carlo type methods are developed that combine the exact and approximate simulation algorithms to exploit their respective advantages. These methods are tailored to keep a global computational error below a prescribed global error tolerance and within a given statistical confidence level. Indeed, the computational work of these methods is similar to the one of an exact method, but with a smaller constant. Finally, the methods are extended to systems with a disparity of time scales. The second part develops novel inference methods to estimate the parameters of Markovian pure jump process. First, an indirect inference approach is presented, which is based on upscaled representations and does not require sampling. This method is simpler than dealing directly with the likelihood of the process, which, in general, cannot be expressed in closed form and whose maximization requires computationally intensive sampling techniques. Second, a forward-reverse Monte Carlo Expectation-Maximization algorithm is provided to approximate a local maximum or saddle point of the likelihood function of the parameters given a set of observations. The third part is devoted to applications in communication networks where also mean field or fluid approximations techniques, to substantially reduce the computational work of simulating large communication networks are explored. These methods aim to capture the global behaviour of systems with large state spaces by using an aggregate approximation, which is often described by means of a non-linear dynamical system. Advisors/Committee Members: Tempone, Raul (advisor), Keyes, David E. (committee member), Gomes, Diogo A. (committee member), Shihada, Basem (committee member), Djehiche, Boualem (committee member).

Subjects/Keywords: inference for continuous-time; Markov Chains; error control; weak approximation; multilevel monte carlo; chernoff tau-leap

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APA (6^th Edition):

Vilanova, P. (2015). Multilevel Approximations of Markovian Jump Processes with Applications in Communication Networks. (Thesis). King Abdullah University of Science and Technology. Retrieved from http://hdl.handle.net/10754/552664

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):

Vilanova, Pedro. “Multilevel Approximations of Markovian Jump Processes with Applications in Communication Networks.” 2015. Thesis, King Abdullah University of Science and Technology. Accessed April 12, 2021. http://hdl.handle.net/10754/552664.

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

MLA Handbook (7^th Edition):

Vilanova, Pedro. “Multilevel Approximations of Markovian Jump Processes with Applications in Communication Networks.” 2015. Web. 12 Apr 2021.

Vancouver:

Vilanova P. Multilevel Approximations of Markovian Jump Processes with Applications in Communication Networks. [Internet] [Thesis]. King Abdullah University of Science and Technology; 2015. [cited 2021 Apr 12]. Available from: http://hdl.handle.net/10754/552664.

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

Council of Science Editors:

Vilanova P. Multilevel Approximations of Markovian Jump Processes with Applications in Communication Networks. [Thesis]. King Abdullah University of Science and Technology; 2015. Available from: http://hdl.handle.net/10754/552664

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

20. Zidan, Mohammed A. Memristor Circuits and Systems.

Degree: Computer, Electrical and Mathematical Sciences and Engineering (CEMSE) Division, 2015, King Abdullah University of Science and Technology

URL: http://hdl.handle.net/10754/552716

► Current CMOS-based technologies are facing design challenges related to the continuous scaling down of the minimum feature size, according to Moore’s law. Moreover, conventional computing… (more)

▼ Current CMOS-based technologies are facing design challenges related to the continuous scaling down of the minimum feature size, according to Moore’s law. Moreover, conventional computing architecture is no longer an effective way of fulfilling modern applications demands, such as big data analysis, pattern recognition, and vector processing. Therefore, there is an exigent need to shift to new technologies, at both the architecture and the device levels. Recently, memristor devices and structures attracted attention for being promising candidates for this job. Memristor device adds a new dimension for designing novel circuits and systems. In addition, high-density memristor-based crossbar is widely considered to be the essential element for future memory and bio-inspired computing systems. However, numerous challenges need to be addressed before the memristor genuinely replaces current memory and computing technologies, which is the motivation behind this research effort. In order to address the technology challenges, we begin by fabricating and modeling the memristor device. The devices fabricated at our local clean room enriched our understanding of the memristive phenomenon and enabled the experimental testing for our memristor-based circuits. Moreover, our proposed mathematical modeling for memristor behavior is an essential element for the theoretical circuit design stage. Designing and addressing the challenges of memristor systems with practical complexity, however, requires an extra step, which takes the form of a reliable and modular simulation platform. We, therefore, built a new simulation platform for the resistive crossbar, which can simulate realistic size arrays filled with real memory data. In addition, this simulation platform includes various crossbar nonidealities in order to obtain accurate simulation results. Consequently, we were able to address the significant challenges facing the high density memristor crossbar, as the building block for resistive-based memory systems and neural computing. For gateless arrays, we present multiport array structure and readout technique, which for the first time introduces a closed-form solution for the challenging crossbar sneak-paths problem. Moreover, a new adaptive threshold readout methodology is proposed, which employs the memory hierarchy locality property in order to improve the access time to the memristor crossbar. Another fast readout technique based on binary counters is presented for locality-less crossbar systems. On the other hand, for gated arrays, we present new readout technique and circuitry that combines the advantages of the gated and gateless memristor arrays, namely the high-density and low-power consumption. In general, the presented structures and readout methodologies empower much faster and power efficient access to the high-density memristive crossbar, compared to other works presented in the literature. Finally, at the circuit level, we propose novel reactance-less oscillators based on memristor devices, which find promising… Advisors/Committee Members: Salama, Khaled N. (advisor), Keyes, David E. (committee member), Hussain, Muhammad Mustafa (committee member), Manchon, Aurelien (committee member), Cheng, Tim K.T. (committee member).

Subjects/Keywords: Memristor; Memory; ReRam; Sneak-Paths; Oscillators; crossbar

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

APA (6^th Edition):

Zidan, M. A. (2015). Memristor Circuits and Systems. (Thesis). King Abdullah University of Science and Technology. Retrieved from http://hdl.handle.net/10754/552716

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):

Zidan, Mohammed A. “Memristor Circuits and Systems.” 2015. Thesis, King Abdullah University of Science and Technology. Accessed April 12, 2021. http://hdl.handle.net/10754/552716.

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

MLA Handbook (7^th Edition):

Zidan, Mohammed A. “Memristor Circuits and Systems.” 2015. Web. 12 Apr 2021.

Vancouver:

Zidan MA. Memristor Circuits and Systems. [Internet] [Thesis]. King Abdullah University of Science and Technology; 2015. [cited 2021 Apr 12]. Available from: http://hdl.handle.net/10754/552716.

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

Council of Science Editors:

Zidan MA. Memristor Circuits and Systems. [Thesis]. King Abdullah University of Science and Technology; 2015. Available from: http://hdl.handle.net/10754/552716

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

King Abdullah University of Science and Technology

21. Wu, Yuanqing. Parallel Reservoir Simulations with Sparse Grid Techniques and Applications to Wormhole Propagation.

Degree: Computer, Electrical and Mathematical Sciences and Engineering (CEMSE) Division, 2015, King Abdullah University of Science and Technology

URL: http://hdl.handle.net/10754/583033

► In this work, two topics of reservoir simulations are discussed. The first topic is the two-phase compositional flow simulation in hydrocarbon reservoir. The major obstacle… (more)

▼ In this work, two topics of reservoir simulations are discussed. The first topic is the two-phase compositional flow simulation in hydrocarbon reservoir. The major obstacle that impedes the applicability of the simulation code is the long run time of the simulation procedure, and thus speeding up the simulation code is necessary. Two means are demonstrated to address the problem: parallelism in physical space and the application of sparse grids in parameter space. The parallel code can gain satisfactory scalability, and the sparse grids can remove the bottleneck of flash calculations. Instead of carrying out the flash calculation in each time step of the simulation, a sparse grid approximation of all possible results of the flash calculation is generated before the simulation. Then the constructed surrogate model is evaluated to approximate the flash calculation results during the simulation. The second topic is the wormhole propagation simulation in carbonate reservoir. In this work, different from the traditional simulation technique relying on the Darcy framework, we propose a new framework called Darcy-Brinkman-Forchheimer framework to simulate wormhole propagation. Furthermore, to process the large quantity of cells in the simulation grid and shorten the long simulation time of the traditional serial code, standard domain-based parallelism is employed, using the Hypre multigrid library. In addition to that, a new technique called “experimenting field approach” to set coefficients in the model equations is introduced. In the 2D dissolution experiments, different configurations of wormholes and a series of properties simulated by both frameworks are compared. We conclude that the numerical results of the DBF framework are more like wormholes and more stable than the Darcy framework, which is a demonstration of the advantages of the DBF framework. The scalability of the parallel code is also evaluated, and good scalability can be achieved. Finally, a mixed finite element scheme is proposed for the wormhole simulation. Advisors/Committee Members: Sun, Shuyu (advisor), Keyes, David E. (committee member), Knio, Omar (committee member), Wu, Yu-Shu (committee member), Cai, Xiaochuan (committee member).

Subjects/Keywords: parallelism; Reservoir simulation; Sparse grids; Wormhole

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APA (6^th Edition):

Wu, Y. (2015). Parallel Reservoir Simulations with Sparse Grid Techniques and Applications to Wormhole Propagation. (Thesis). King Abdullah University of Science and Technology. Retrieved from http://hdl.handle.net/10754/583033

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):

Wu, Yuanqing. “Parallel Reservoir Simulations with Sparse Grid Techniques and Applications to Wormhole Propagation.” 2015. Thesis, King Abdullah University of Science and Technology. Accessed April 12, 2021. http://hdl.handle.net/10754/583033.

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

MLA Handbook (7^th Edition):

Wu, Yuanqing. “Parallel Reservoir Simulations with Sparse Grid Techniques and Applications to Wormhole Propagation.” 2015. Web. 12 Apr 2021.

Vancouver:

Wu Y. Parallel Reservoir Simulations with Sparse Grid Techniques and Applications to Wormhole Propagation. [Internet] [Thesis]. King Abdullah University of Science and Technology; 2015. [cited 2021 Apr 12]. Available from: http://hdl.handle.net/10754/583033.

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

Council of Science Editors:

Wu Y. Parallel Reservoir Simulations with Sparse Grid Techniques and Applications to Wormhole Propagation. [Thesis]. King Abdullah University of Science and Technology; 2015. Available from: http://hdl.handle.net/10754/583033

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

22. Elrasad, Amr. Efficient Bandwidth Management for Ethernet Passive Optical Networks.

Degree: Computer, Electrical and Mathematical Sciences and Engineering (CEMSE) Division, 2016, King Abdullah University of Science and Technology

URL: http://hdl.handle.net/10754/609535

► The increasing bandwidth demands in access networks motivates network operators, networking devices manufacturers, and standardization institutions to search for new approaches for access networks. These… (more)

▼ The increasing bandwidth demands in access networks motivates network operators, networking devices manufacturers, and standardization institutions to search for new approaches for access networks. These approaches should support higher bandwidth, longer distance between end user and network operator, and less energy consumption. Ethernet Passive Optical Network (EPON) is a favorable choice for broadband access networks. EPONs support transmission rates up to 10 Gbps. EPONs also support distance between end users and central office up to 20 Km. Moreover, optical networks have the least energy consumption among all types of networks. In this dissertation, we focus on reducing delay and saving energy in EPONs. Reducing delay is essential for delay-sensitive traffic, while minimizing energy consumption is an environmental necessity and also reduces the network operating costs. We identify five challenges, namely excess bandwidth allocation, frame delineation, congestion resolution, large round trip time delay in long-reach EPONs (LR-EPONs), and energy saving. We provide a Dynamic Bandwidth Allocation (DBA) approach for each challenge. We also propose a novel scheme that combines the features of the proposed approaches in one highly performing scheme. Our approach is to design novel DBA protocols that can further reduce the delay and be simultaneously simple and fair. We also present a dynamic bandwidth allocation scheme for Green EPONs taking into consideration maximizing energy saving under target delay constraints. Regarding excess bandwidth allocation, we develop an effective DBA scheme called Delayed Excess Scheduling (DES). DES achieves significant delay and jitter reduction and is more suitable for industrial deployment due to its simplicity. Utilizing DES in hybrid TDM/WDM EPONs (TWDM-EPONs) is also investigated. We also study eliminating the wasted bandwidth due to frame delineation. We develop an interactive DBA scheme, Efficient Grant Sizing Interleaved Polling (EGSIP), to compensate the unutilized bandwidth due to frame delineation. Our solution achieves delay reduction ratio up to 90% at high load. We also develop a Congestion Aware Limited Time (CALT) DBA scheme to detect and resolve temporary congestion in EPONs. CALT smartly adapts the optical networking unit (ONU) maximum transmission window according to the detected congestion level. Numerical results show that CALT is more robust at high load compared to other related published schemes. Regarding LR-EPONs, the main concern is large round trip delay mitigation. We address two problems, namely bandwidth over-granting in Multi-Thread Polling (MTP) and on-the-fly void filling. We combine, with some modifications, EGSIP and DES to resolve bandwidth over-granting in MTP. We also manage to adaptively tune MTP active running threads along with the offered load. Regarding on-the-fly void filling, Our approach, Parallel Void Thread (PVT), achieves large delay reduction for delay-sensitive traffic. PVT is designed as a plus function to DBA and can be… Advisors/Committee Members: Shihada, Basem (advisor), Keyes, David E. (committee member), Alouini, Mohamed-Slim (committee member), Mukherjee, Biswanath (committee member).

Subjects/Keywords: Passive optical network; dynamic bandwidth allocation; polling models; energy efficiency

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APA (6^th Edition):

Elrasad, A. (2016). Efficient Bandwidth Management for Ethernet Passive Optical Networks. (Thesis). King Abdullah University of Science and Technology. Retrieved from http://hdl.handle.net/10754/609535

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):

Elrasad, Amr. “Efficient Bandwidth Management for Ethernet Passive Optical Networks.” 2016. Thesis, King Abdullah University of Science and Technology. Accessed April 12, 2021. http://hdl.handle.net/10754/609535.

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

MLA Handbook (7^th Edition):

Elrasad, Amr. “Efficient Bandwidth Management for Ethernet Passive Optical Networks.” 2016. Web. 12 Apr 2021.

Vancouver:

Elrasad A. Efficient Bandwidth Management for Ethernet Passive Optical Networks. [Internet] [Thesis]. King Abdullah University of Science and Technology; 2016. [cited 2021 Apr 12]. Available from: http://hdl.handle.net/10754/609535.

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

Council of Science Editors:

Elrasad A. Efficient Bandwidth Management for Ethernet Passive Optical Networks. [Thesis]. King Abdullah University of Science and Technology; 2016. Available from: http://hdl.handle.net/10754/609535

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

King Abdullah University of Science and Technology

23. Ibeid, Huda. Fast Multipole-Based Elliptic PDE Solver and Preconditioner.

Degree: Computer, Electrical and Mathematical Sciences and Engineering (CEMSE) Division, 2016, King Abdullah University of Science and Technology

URL: http://hdl.handle.net/10754/621993

► Exascale systems are predicted to have approximately one billion cores, assuming Gigahertz cores. Limitations on affordable network topologies for distributed memory systems of such massive… (more)

▼ Exascale systems are predicted to have approximately one billion cores, assuming Gigahertz cores. Limitations on affordable network topologies for distributed memory systems of such massive scale bring new challenges to the currently dominant parallel programing model. Currently, there are many efforts to evaluate the hardware and software bottlenecks of exascale designs. It is therefore of interest to model application performance and to understand what changes need to be made to ensure extrapolated scalability. Fast multipole methods (FMM) were originally developed for accelerating N-body problems for particle-based methods in astrophysics and molecular dynamics. FMM is more than an N-body solver, however. Recent efforts to view the FMM as an elliptic PDE solver have opened the possibility to use it as a preconditioner for even a broader range of applications. In this thesis, we (i) discuss the challenges for FMM on current parallel computers and future exascale architectures, with a focus on inter-node communication, and develop a performance model that considers the communication patterns of the FMM for spatially quasi-uniform distributions, (ii) employ this performance model to guide performance and scaling improvement of FMM for all-atom molecular dynamics simulations of uniformly distributed particles, and (iii) demonstrate that, beyond its traditional use as a solver in problems for which explicit free-space kernel representations are available, the FMM has applicability as a preconditioner in finite domain elliptic boundary value problems, by equipping it with boundary integral capability for satisfying conditions at finite boundaries and by wrapping it in a Krylov method for extensibility to more general operators. Compared with multilevel methods, FMM is capable of comparable algebraic convergence rates down to the truncation error of the discretized PDE, and it has superior multicore and distributed memory scalability properties on commodity architecture supercomputers. Compared with other methods exploiting the low rank character of off-diagonal blocks of the dense resolvent operator, FMM-preconditioned Krylov iteration may reduce the amount of communication because it is matrix-free and exploits the tree structure of FMM. Fast multipole-based solvers and preconditioners are demonstrably poised to play a leading role in exascale computing. Advisors/Committee Members: Keyes, David E. (advisor), Bagci, Hakan (committee member), Gao, Xin (committee member), Yokota, Rio (committee member), Gropp, William D. (committee member).

Subjects/Keywords: Fast Multiple Method; Performance modeling; Boundary element method; Preconditioning

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

APA (6^th Edition):

Ibeid, H. (2016). Fast Multipole-Based Elliptic PDE Solver and Preconditioner. (Thesis). King Abdullah University of Science and Technology. Retrieved from http://hdl.handle.net/10754/621993

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):

Ibeid, Huda. “Fast Multipole-Based Elliptic PDE Solver and Preconditioner.” 2016. Thesis, King Abdullah University of Science and Technology. Accessed April 12, 2021. http://hdl.handle.net/10754/621993.

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

MLA Handbook (7^th Edition):

Ibeid, Huda. “Fast Multipole-Based Elliptic PDE Solver and Preconditioner.” 2016. Web. 12 Apr 2021.

Vancouver:

Ibeid H. Fast Multipole-Based Elliptic PDE Solver and Preconditioner. [Internet] [Thesis]. King Abdullah University of Science and Technology; 2016. [cited 2021 Apr 12]. Available from: http://hdl.handle.net/10754/621993.

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

Council of Science Editors:

Ibeid H. Fast Multipole-Based Elliptic PDE Solver and Preconditioner. [Thesis]. King Abdullah University of Science and Technology; 2016. Available from: http://hdl.handle.net/10754/621993

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

King Abdullah University of Science and Technology

24. Chavez Chavez, Gustavo Ivan. Robust and scalable hierarchical matrix-based fast direct solver and preconditioner for the numerical solution of elliptic partial differential equations.

Degree: Computer, Electrical and Mathematical Sciences and Engineering (CEMSE) Division, 2017, King Abdullah University of Science and Technology

URL: http://hdl.handle.net/10754/625172

► This dissertation introduces a novel fast direct solver and preconditioner for the solution of block tridiagonal linear systems that arise from the discretization of elliptic… (more)

▼ This dissertation introduces a novel fast direct solver and preconditioner for the solution of block tridiagonal linear systems that arise from the discretization of elliptic partial differential equations on a Cartesian product mesh, such as the variable-coefficient Poisson equation, the convection-diffusion equation, and the wave Helmholtz equation in heterogeneous media. The algorithm extends the traditional cyclic reduction method with hierarchical matrix techniques. The resulting method exposes substantial concurrency, and its arithmetic operations and memory consumption grow only log-linearly with problem size, assuming bounded rank of off-diagonal matrix blocks, even for problems with arbitrary coefficient structure. The method can be used as a standalone direct solver with tunable accuracy, or as a black-box preconditioner in conjunction with Krylov methods. The challenges that distinguish this work from other thrusts in this active field are the hybrid distributed-shared parallelism that can demonstrate the algorithm at large-scale, full three-dimensionality, and the three stressors of the current state-of-the-art multigrid technology: high wavenumber Helmholtz (indefiniteness), high Reynolds convection (nonsymmetry), and high contrast diffusion (inhomogeneity). Numerical experiments corroborate the robustness, accuracy, and complexity claims and provide a baseline of the performance and memory footprint by comparisons with competing approaches such as the multigrid solver hypre, and the STRUMPACK implementation of the multifrontal factorization with hierarchically semi-separable matrices. The companion implementation can utilize many thousands of cores of Shaheen, KAUST's Haswell-based Cray XC-40 supercomputer, and compares favorably with other implementations of hierarchical solvers in terms of time-to-solution and memory consumption. Advisors/Committee Members: Keyes, David E. (advisor), Moshkov, Mikhail (committee member), Ketcheson, David I. (committee member), Turkiyyah, George (committee member), Huang, Jingfang (committee member).

Subjects/Keywords: hierarchical matrices; cyclic reduction; fast solvers; Direct solvers; preconditioning; Parallel Computing

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APA (6^th Edition):

Chavez Chavez, G. I. (2017). Robust and scalable hierarchical matrix-based fast direct solver and preconditioner for the numerical solution of elliptic partial differential equations. (Thesis). King Abdullah University of Science and Technology. Retrieved from http://hdl.handle.net/10754/625172

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):

Chavez Chavez, Gustavo Ivan. “Robust and scalable hierarchical matrix-based fast direct solver and preconditioner for the numerical solution of elliptic partial differential equations.” 2017. Thesis, King Abdullah University of Science and Technology. Accessed April 12, 2021. http://hdl.handle.net/10754/625172.

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

MLA Handbook (7^th Edition):

Chavez Chavez, Gustavo Ivan. “Robust and scalable hierarchical matrix-based fast direct solver and preconditioner for the numerical solution of elliptic partial differential equations.” 2017. Web. 12 Apr 2021.

Vancouver:

Chavez Chavez GI. Robust and scalable hierarchical matrix-based fast direct solver and preconditioner for the numerical solution of elliptic partial differential equations. [Internet] [Thesis]. King Abdullah University of Science and Technology; 2017. [cited 2021 Apr 12]. Available from: http://hdl.handle.net/10754/625172.

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

Council of Science Editors:

Chavez Chavez GI. Robust and scalable hierarchical matrix-based fast direct solver and preconditioner for the numerical solution of elliptic partial differential equations. [Thesis]. King Abdullah University of Science and Technology; 2017. Available from: http://hdl.handle.net/10754/625172

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

King Abdullah University of Science and Technology

25. Huang, Huang. Computational Methods for Large Spatio-temporal Datasets and Functional Data Ranking.

Degree: Computer, Electrical and Mathematical Sciences and Engineering (CEMSE) Division, 2017, King Abdullah University of Science and Technology

URL: http://hdl.handle.net/10754/625200

► This thesis focuses on two topics, computational methods for large spatial datasets and functional data ranking. Both are tackling the challenges of big and high-dimensional… (more)

▼ This thesis focuses on two topics, computational methods for large spatial datasets and functional data ranking. Both are tackling the challenges of big and high-dimensional data. The first topic is motivated by the prohibitive computational burden in fitting Gaussian process models to large and irregularly spaced spatial datasets. Various approximation methods have been introduced to reduce the computational cost, but many rely on unrealistic assumptions about the process and retaining statistical efficiency remains an issue. We propose a new scheme to approximate the maximum likelihood estimator and the kriging predictor when the exact computation is infeasible. The proposed method provides different types of hierarchical low-rank approximations that are both computationally and statistically efficient. We explore the improvement of the approximation theoretically and investigate the performance by simulations. For real applications, we analyze a soil moisture dataset with 2 million measurements with the hierarchical low-rank approximation and apply the proposed fast kriging to fill gaps for satellite images. The second topic is motivated by rank-based outlier detection methods for functional data. Compared to magnitude outliers, it is more challenging to detect shape outliers as they are often masked among samples. We develop a new notion of functional data depth by taking the integration of a univariate depth function. Having a form of the integrated depth, it shares many desirable features. Furthermore, the novel formation leads to a useful decomposition for detecting both shape and magnitude outliers. Our simulation studies show the proposed outlier detection procedure outperforms competitors in various outlier models. We also illustrate our methodology using real datasets of curves, images, and video frames. Finally, we introduce the functional data ranking technique to spatio-temporal statistics for visualizing and assessing covariance properties, such as separability and full symmetry. We formulate test functions as functions of temporal lags for each pair of spatial locations and develop a rank-based testing procedure induced by functional data depth for assessing these properties. The method is illustrated using simulated data from widely used spatio-temporal covariance models, as well as real datasets from weather stations and climate model outputs. Advisors/Committee Members: Sun, Ying (advisor), Alouini, Mohamed-Slim (committee member), Genton, Marc G. (committee member), Keyes, David E. (committee member).

Subjects/Keywords: Large spatial data set; low rank approximation; Functional Data Analysis; spatio-temporal covariance; Statistical efficiency; Outlier detection

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APA (6^th Edition):

Huang, H. (2017). Computational Methods for Large Spatio-temporal Datasets and Functional Data Ranking. (Thesis). King Abdullah University of Science and Technology. Retrieved from http://hdl.handle.net/10754/625200

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):

Huang, Huang. “Computational Methods for Large Spatio-temporal Datasets and Functional Data Ranking.” 2017. Thesis, King Abdullah University of Science and Technology. Accessed April 12, 2021. http://hdl.handle.net/10754/625200.

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

MLA Handbook (7^th Edition):

Huang, Huang. “Computational Methods for Large Spatio-temporal Datasets and Functional Data Ranking.” 2017. Web. 12 Apr 2021.

Vancouver:

Huang H. Computational Methods for Large Spatio-temporal Datasets and Functional Data Ranking. [Internet] [Thesis]. King Abdullah University of Science and Technology; 2017. [cited 2021 Apr 12]. Available from: http://hdl.handle.net/10754/625200.

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

Council of Science Editors:

Huang H. Computational Methods for Large Spatio-temporal Datasets and Functional Data Ranking. [Thesis]. King Abdullah University of Science and Technology; 2017. Available from: http://hdl.handle.net/10754/625200

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

King Abdullah University of Science and Technology

26. Majeed, Muhammad Usman. Iterative Observer-based Estimation Algorithms for Steady-State Elliptic Partial Differential Equation Systems.

Degree: Computer, Electrical and Mathematical Sciences and Engineering (CEMSE) Division, 2017, King Abdullah University of Science and Technology

URL: http://hdl.handle.net/10754/625240

► Steady-state elliptic partial differential equations (PDEs) are frequently used to model a diverse range of physical phenomena. The source and boundary data estimation problems for… (more)

▼ Steady-state elliptic partial differential equations (PDEs) are frequently used to model a diverse range of physical phenomena. The source and boundary data estimation problems for such PDE systems are of prime interest in various engineering disciplines including biomedical engineering, mechanics of materials and earth sciences. Almost all existing solution strategies for such problems can be broadly classified as optimization-based techniques, which are computationally heavy especially when the problems are formulated on higher dimensional space domains. However, in this dissertation, feedback based state estimation algorithms, known as state observers, are developed to solve such steady-state problems using one of the space variables as time-like. In this regard, first, an iterative observer algorithm is developed that sweeps over regular-shaped domains and solves boundary estimation problems for steady-state Laplace equation. It is well-known that source and boundary estimation problems for the elliptic PDEs are highly sensitive to noise in the data. For this, an optimal iterative observer algorithm, which is a robust counterpart of the iterative observer, is presented to tackle the ill-posedness due to noise. The iterative observer algorithm and the optimal iterative algorithm are then used to solve source localization and estimation problems for Poisson equation for noise-free and noisy data cases respectively. Next, a divide and conquer approach is developed for three-dimensional domains with two congruent parallel surfaces to solve the boundary and the source data estimation problems for the steady-state Laplace and Poisson kind of systems respectively. Theoretical results are shown using a functional analysis framework, and consistent numerical simulation results are presented for several test cases using finite difference discretization schemes. Advisors/Committee Members: Laleg-Kirati, Taous-Meriem (advisor), Shamma, Jeff S. (committee member), Keyes, David E. (committee member), Wu, Ying (committee member), Smith, Ralph (committee member).

Subjects/Keywords: observer design; Inverse problems; Boundary Estimation; source localization; elliptic PDEs; kalman filter

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APA (6^th Edition):

Majeed, M. U. (2017). Iterative Observer-based Estimation Algorithms for Steady-State Elliptic Partial Differential Equation Systems. (Thesis). King Abdullah University of Science and Technology. Retrieved from http://hdl.handle.net/10754/625240

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):

Majeed, Muhammad Usman. “Iterative Observer-based Estimation Algorithms for Steady-State Elliptic Partial Differential Equation Systems.” 2017. Thesis, King Abdullah University of Science and Technology. Accessed April 12, 2021. http://hdl.handle.net/10754/625240.

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

MLA Handbook (7^th Edition):

Majeed, Muhammad Usman. “Iterative Observer-based Estimation Algorithms for Steady-State Elliptic Partial Differential Equation Systems.” 2017. Web. 12 Apr 2021.

Vancouver:

Majeed MU. Iterative Observer-based Estimation Algorithms for Steady-State Elliptic Partial Differential Equation Systems. [Internet] [Thesis]. King Abdullah University of Science and Technology; 2017. [cited 2021 Apr 12]. Available from: http://hdl.handle.net/10754/625240.

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

Council of Science Editors:

Majeed MU. Iterative Observer-based Estimation Algorithms for Steady-State Elliptic Partial Differential Equation Systems. [Thesis]. King Abdullah University of Science and Technology; 2017. Available from: http://hdl.handle.net/10754/625240

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

King Abdullah University of Science and Technology

27. Felício dos Reis, João Miguel. Stability of BDF-ADI Discretizations.

Degree: Computer, Electrical and Mathematical Sciences and Engineering (CEMSE) Division, 2017, King Abdullah University of Science and Technology

URL: http://hdl.handle.net/10754/625356

► We present new results on absolute stability for BDF-ADI (Backward differentiation formula Alternating Direction Implicit) methods applied to a linear advection and diffusion equations. Unconditional… (more)

Subjects/Keywords: Numerical analysis; Splitting methods; BDF-ADI; absolute stability; scour-cohn algorithm

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

APA (6^th Edition):

Felício dos Reis, J. M. (2017). Stability of BDF-ADI Discretizations. (Thesis). King Abdullah University of Science and Technology. Retrieved from http://hdl.handle.net/10754/625356

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):

Felício dos Reis, João Miguel. “Stability of BDF-ADI Discretizations.” 2017. Thesis, King Abdullah University of Science and Technology. Accessed April 12, 2021. http://hdl.handle.net/10754/625356.

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

MLA Handbook (7^th Edition):

Felício dos Reis, João Miguel. “Stability of BDF-ADI Discretizations.” 2017. Web. 12 Apr 2021.

Vancouver:

Felício dos Reis JM. Stability of BDF-ADI Discretizations. [Internet] [Thesis]. King Abdullah University of Science and Technology; 2017. [cited 2021 Apr 12]. Available from: http://hdl.handle.net/10754/625356.

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

Council of Science Editors:

Felício dos Reis JM. Stability of BDF-ADI Discretizations. [Thesis]. King Abdullah University of Science and Technology; 2017. Available from: http://hdl.handle.net/10754/625356

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

King Abdullah University of Science and Technology

28. Hadjimichael, Yiannis. Perturbed Strong Stability Preserving Time-Stepping Methods For Hyperbolic PDEs.

Degree: Computer, Electrical and Mathematical Sciences and Engineering (CEMSE) Division, 2017, King Abdullah University of Science and Technology

URL: http://hdl.handle.net/10754/625526

► A plethora of physical phenomena are modelled by hyperbolic partial differential equations, for which the exact solution is usually not known. Numerical methods are employed… (more)

▼ A plethora of physical phenomena are modelled by hyperbolic partial differential equations, for which the exact solution is usually not known. Numerical methods are employed to approximate the solution to hyperbolic problems; however, in many cases it is difficult to satisfy certain physical properties while maintaining high order of accuracy. In this thesis, we develop high-order time-stepping methods that are capable of maintaining stability constraints of the solution, when coupled with suitable spatial discretizations. Such methods are called strong stability preserving (SSP) time integrators, and we mainly focus on perturbed methods that use both upwind- and downwind-biased spatial discretizations. Firstly, we introduce a new family of third-order implicit Runge–Kuttas methods with arbitrarily large SSP coefficient. We investigate the stability and accuracy of these methods and we show that they perform well on hyperbolic problems with large CFL numbers. Moreover, we extend the analysis of SSP linear multistep methods to semi-discretized problems for which different terms on the right-hand side of the initial value problem satisfy different forward Euler (or circle) conditions. Optimal perturbed and additive monotonicity-preserving linear multistep methods are studied in the context of such problems. Optimal perturbed methods attain augmented monotonicity-preserving step sizes when the different forward Euler conditions are taken into account. On the other hand, we show that optimal SSP additive methods achieve a monotonicity-preserving step-size restriction no better than that of the corresponding non-additive SSP linear multistep methods. Furthermore, we develop the first SSP linear multistep methods of order two and three with variable step size, and study their optimality. We describe an optimal step-size strategy and demonstrate the effectiveness of these methods on various one- and multi-dimensional problems. Finally, we establish necessary conditions to preserve the total variation of the solution obtained when perturbed methods are applied to boundary value problems. We implement a stable treatment of nonreflecting boundary conditions for hyperbolic problems that allows high order of accuracy and controls spurious wave reflections. Numerical examples with high-order perturbed Runge–Kutta methods reveal that this technique provides a significant improvement in accuracy compared with zero-order extrapolation. Advisors/Committee Members: Ketcheson, David I. (advisor), Keyes, David E. (committee member), Samtaney, Ravi (committee member), Tzavaras, Athanasios (committee member), Higueras, Inmaculada (committee member).

Subjects/Keywords: time-integration; strong stability preservation; Runge-Kutta; linear multistep methods; Hyperbolic PDE

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

APA (6^th Edition):

Hadjimichael, Y. (2017). Perturbed Strong Stability Preserving Time-Stepping Methods For Hyperbolic PDEs. (Thesis). King Abdullah University of Science and Technology. Retrieved from http://hdl.handle.net/10754/625526

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):

Hadjimichael, Yiannis. “Perturbed Strong Stability Preserving Time-Stepping Methods For Hyperbolic PDEs.” 2017. Thesis, King Abdullah University of Science and Technology. Accessed April 12, 2021. http://hdl.handle.net/10754/625526.

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

MLA Handbook (7^th Edition):

Hadjimichael, Yiannis. “Perturbed Strong Stability Preserving Time-Stepping Methods For Hyperbolic PDEs.” 2017. Web. 12 Apr 2021.

Vancouver:

Hadjimichael Y. Perturbed Strong Stability Preserving Time-Stepping Methods For Hyperbolic PDEs. [Internet] [Thesis]. King Abdullah University of Science and Technology; 2017. [cited 2021 Apr 12]. Available from: http://hdl.handle.net/10754/625526.

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

Council of Science Editors:

Hadjimichael Y. Perturbed Strong Stability Preserving Time-Stepping Methods For Hyperbolic PDEs. [Thesis]. King Abdullah University of Science and Technology; 2017. Available from: http://hdl.handle.net/10754/625526

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

King Abdullah University of Science and Technology

29. Sarmiento, Adel. Structure-Preserving Methods for the Navier-Stokes-Cahn-Hilliard System to Model Immiscible Fluids.

Degree: Computer, Electrical and Mathematical Sciences and Engineering (CEMSE) Division, 2017, King Abdullah University of Science and Technology

URL: http://hdl.handle.net/10754/626270

► This work presents a novel method to model immiscible incompressible fluids in a stable manner. Here, the immiscible behavior of the flow is described by… (more)

▼ This work presents a novel method to model immiscible incompressible fluids in a stable manner. Here, the immiscible behavior of the flow is described by the incompressible Navier-Stokes-Cahn-Hilliard model, which is based on a diffuse interface method. We introduce buoyancy effects in the model through the Boussinesq approximation in a consistent manner. A structure-preserving discretization is used to guarantee the linear stability of the discrete problem and to satisfy the incompressibility of the discrete solution at every point in space by construction. For the solution of the model, we developed the Portable Extensible Toolkit for Isogeometric Analysis with Multi-Field discretizations (PetIGA-MF), a high-performance framework that supports structure-preserving spaces. PetIGA-MF is built on top of PetIGA and the Portable Extensible Toolkit for Scientific Computation (PETSc), sharing all their user-friendly, performance, and flexibility features. Herein, we describe the implementation of our model in PetIGA-MF and the details of the numerical solution. With several numerical tests, we verify the convergence, scalability, and validity of our approach. We use highly-resolved numerical simulations to analyze the merging and rising of droplets. From these simulations, we detailed the energy exchanges in the system to evaluate quantitatively the quality of our simulations. The good agreement of our results when compared against theoretical descriptions of the merging, and the small errors found in the energy analysis, allow us to validate our approach. Additionally, we present the development of an unconditionally energy-stable generalized-alpha method for the Swift-Hohenberg model that offers control over the numerical dissipation. A pattern formation example demonstrates the energy-stability and convergence of our method. Advisors/Committee Members: Parsani, Matteo (advisor), Calo, Victor M. (advisor), Keyes, David E. (committee member), Sun, Shuyu (committee member), Efendiev, Yalchin R. (committee member).

Subjects/Keywords: immiscible; incompressible; structure-preserving; divergence-conforming; Navier-Stokes-Cahn-Hilliard

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

APA (6^th Edition):

Sarmiento, A. (2017). Structure-Preserving Methods for the Navier-Stokes-Cahn-Hilliard System to Model Immiscible Fluids. (Thesis). King Abdullah University of Science and Technology. Retrieved from http://hdl.handle.net/10754/626270

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):

Sarmiento, Adel. “Structure-Preserving Methods for the Navier-Stokes-Cahn-Hilliard System to Model Immiscible Fluids.” 2017. Thesis, King Abdullah University of Science and Technology. Accessed April 12, 2021. http://hdl.handle.net/10754/626270.

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

MLA Handbook (7^th Edition):

Sarmiento, Adel. “Structure-Preserving Methods for the Navier-Stokes-Cahn-Hilliard System to Model Immiscible Fluids.” 2017. Web. 12 Apr 2021.

Vancouver:

Sarmiento A. Structure-Preserving Methods for the Navier-Stokes-Cahn-Hilliard System to Model Immiscible Fluids. [Internet] [Thesis]. King Abdullah University of Science and Technology; 2017. [cited 2021 Apr 12]. Available from: http://hdl.handle.net/10754/626270.

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

Council of Science Editors:

Sarmiento A. Structure-Preserving Methods for the Navier-Stokes-Cahn-Hilliard System to Model Immiscible Fluids. [Thesis]. King Abdullah University of Science and Technology; 2017. Available from: http://hdl.handle.net/10754/626270

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

King Abdullah University of Science and Technology

30. Bakhsh, Abeer. Linear Analyses of Magnetohydrodynamic Richtmyer-Meshkov Instability in Cylindrical Geometry.

Degree: Computer, Electrical and Mathematical Sciences and Engineering (CEMSE) Division, 2018, King Abdullah University of Science and Technology

URL: http://hdl.handle.net/10754/627830

► We investigate the Richtmyer-Meshkov instability (RMI) that occurs when an incident shock impulsively accelerates the interface between two different fluids. RMI is important in many… (more)

▼ We investigate the Richtmyer-Meshkov instability (RMI) that occurs when an incident shock impulsively accelerates the interface between two different fluids. RMI is important in many technological applications such as Inertial Confinement Fusion (ICF) and astrophysical phenomena such as supernovae. We consider RMI in the presence of the magnetic field in converging geometry through both simulations and analytical means in the framework of ideal magnetohydrodynamics (MHD). In this thesis, we perform linear stability analyses via simulations in the cylindrical geometry, which is of relevance to ICF. In converging geometry, RMI is usually followed by the Rayleigh-Taylor instability (RTI). We show that the presence of a magnetic field suppresses the instabilities. We study the influence of the strength of the magnetic field, perturbation wavenumbers and other relevant parameters on the evolution of the RM and RT instabilities. First, we perform linear stability simulations for a single interface between two different fluids in which the magnetic field is normal to the direction of the average motion of the density interface. The suppression of the instabilities is most evident for large wavenumbers and relatively strong magnetic fields strengths. The mechanism of suppression is the transport of vorticity away from the density interface by two Alfv ́en fronts. Second, we examine the case of an azimuthal magnetic field at the density interface. The most evident suppression of the instability at the interface is for large wavenumbers and relatively strong magnetic fields strengths. After the shock interacts with the interface, the emerging vorticity breaks up into waves traveling parallel and anti-parallel to the magnetic field. The interference as these waves propagate with alternating phase causing the perturbation growth rate of the interface to oscillate in time. Finally, we propose incompressible models for MHD RMI in the presence of normal or azimuthal magnetic field. The linearized equations are solved numerically using inverse Laplace transform. The incompressible models show that the magnetic field suppresses the RMI, and the mechanism of this suppression depends on the orientation of the initially applied magnetic field. The incompressible model agrees reasonably well with compressible linear simulations. Advisors/Committee Members: Samtaney, Ravi (advisor), Keyes, David E. (committee member), Kasimov, Aslan R. (committee member), Wheatley, V. (committee member).

Subjects/Keywords: Richtmyer-Meshkov; Magnetohydrodynamics; incompressible model; Rayleigh-Taylor instability; Cylindrical Geometry; Compressible flow

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

APA (6^th Edition):

Bakhsh, A. (2018). Linear Analyses of Magnetohydrodynamic Richtmyer-Meshkov Instability in Cylindrical Geometry. (Thesis). King Abdullah University of Science and Technology. Retrieved from http://hdl.handle.net/10754/627830

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):

Bakhsh, Abeer. “Linear Analyses of Magnetohydrodynamic Richtmyer-Meshkov Instability in Cylindrical Geometry.” 2018. Thesis, King Abdullah University of Science and Technology. Accessed April 12, 2021. http://hdl.handle.net/10754/627830.

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

MLA Handbook (7^th Edition):

Bakhsh, Abeer. “Linear Analyses of Magnetohydrodynamic Richtmyer-Meshkov Instability in Cylindrical Geometry.” 2018. Web. 12 Apr 2021.

Vancouver:

Bakhsh A. Linear Analyses of Magnetohydrodynamic Richtmyer-Meshkov Instability in Cylindrical Geometry. [Internet] [Thesis]. King Abdullah University of Science and Technology; 2018. [cited 2021 Apr 12]. Available from: http://hdl.handle.net/10754/627830.

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

Council of Science Editors:

Bakhsh A. Linear Analyses of Magnetohydrodynamic Richtmyer-Meshkov Instability in Cylindrical Geometry. [Thesis]. King Abdullah University of Science and Technology; 2018. Available from: http://hdl.handle.net/10754/627830

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