236 Works

Bose-Einstein Condensation of Light in Disordered Nano Cavities at Room Temperature

Andris Erglis
Bose-Einstein Condensation is a macroscopic occupation of bosons in the lowest energy state. For atoms, extremely low temperatures are required to observe this phenomenon. For photons, condensation has been demonstrated at room temperature, requiring a large number of particles (N ∼ 77000) and very complicated setup. Here we study the possibility of observing BEC of light at room temperature with a much lower number of particles by leveraging disorder in a dielectric material. There is...

Design, fabrication and application of fractional-order capacitors

Agamyrat Agambayev
The fractional–order capacitors add an additional degree of freedom over conventional capacitors in circuit design and facilitate circuit configurations that would be impractical or impossible to implement with conventional capacitors. We propose a generic strategy for fractional-order capacitor fabrication that integrates layers of conductive, semiconductor and ferroelectric polymer materials to create a composite with significantly improved constant phase angle, constant phase zone, and phase angle variation performance. Our approach involves a combination of dissolving the...

Shallow Soft Sediment Communities in the Central Red Sea: Revealing Patterns in Community Structure across Space and Time

Zahra Hassan Ali Alsaffar
Due to intensive coastal development, a combination of local (e.g. pollution, fishing) and global pressures (such as climate change) is affecting marine habitats worldwide. This is a pressing issue in Saudi Arabia, particularly considering the plans for the expansion of sea-related activities within the Saudi Arabia's Vision 2030 framework. Sustaining some of those activities, such as tourism, is dependent upon the maintenance of good ecosystem health. National monitoring programs in Saudi Arabia are scarce and...

Structural Analysis of Arabidopsis thaliana CDC48A ATPase using Single Particle Cryo-Electron Microscopy

Lila A. Aldakheel
Cdc48A and its human homologue P97 are from ATPase family, which play a variety of roles in cellular activates and it has a crucial involvement in protein quality control pathways. It is best known for its involvement in endoplasmic reticulum associated protein degradation (ERAD), where it mediates the degradation of the aggerated or misfolded proteins by the proteasome. Considering the multiple functions of Cdc48A in many protein regulatory processes, it is a potential therapeutic target...

Engineering Plasmonic Nanostructures and Their Application in Bioanalysis

Yang Zhang
Plasmonic nanostructures, like noble metal, have gained large attention due to their plasmonic properties so they can reach areas like electronics, photo-catalysis, biomedicine, and sensing. Plasmonic nanomaterials are known for their local surface plasmon resonance and enhanced electromagnetic field and wavelength dependence. The higher the electromagnetic field at the surface of the nanoparticles can interact with nearby molecules, the bigger the influence is on the intensity of the molecule signals. This phenomenon is called surface-enhanced...

Power Adaption Over Fluctuating Two-Ray Fading Channels and Fisher-Snedecor F Fading Channels

Hui Zhao
In this thesis, we investigate the ergodic capacity under several power adaption schemes, including optimal power and rate algorithm (OPRA), optimal rate algo rithm (ORA), channel inversion (CI), and truncated channel inversion (TCI), over fluctuating two-ray (FTR) fading channels and Fisher-Snedecor F fading channels. After some mathematical manipulations, the exact expressions for the EC under those power adaption schemes are derived. To simplify the expressions and also get some insights from the analysis, the corresponding...

Novel Nanofibrous Peptide Scaffolds for Tissue Regeneration

Wafaa Arab
A huge discrepancy between the number of patients on the waiting list for organ transplants and the actual available donors has led to search for alternative approaches to substitute compromised or missing tissues and organs. Tissue engineering is a promising alternative to organ transplantation with the aim to fabricate functional organs through the use of biological or biocompatible scaffolds. Nanogels made from self-assembling ultrashort peptides are promising biomaterials for a variety of biomedical applications. Our...

Unstructured Computations on Emerging Architectures

Mohammed Al Farhan
This dissertation describes detailed performance engineering and optimization of an unstructured computational aerodynamics software system with irregular memory accesses on various multi- and many-core emerging high performance computing scalable architectures, which are expected to be the building blocks of energy-austere exascale systems, and on which algorithmic- and architecture-oriented optimizations are essential for achieving worthy performance. We investigate several state-of-the-practice shared-memory optimization techniques applied to key kernels for the important problem class of unstructured meshes. We...

Uncertainty Quantification and Assimilation for Efficient Coastal Ocean Forecasting

Adil Siripatana
Bayesian inference is commonly used to quantify and reduce modeling uncertainties in coastal ocean models by computing the posterior probability distribution function (pdf) of some uncertain quantities to be estimated conditioned on available observations. The posterior can be computed either directly, using a Markov Chain Monte Carlo (MCMC) approach, or by sequentially processing the data following a data assimilation (DA) approach. The advantage of data assimilation schemes over MCMC-type methods arises from the ability to...

Electrothermally Tuned and Electrostatically Actuated MEMS Resonators: Dynamics and Applications

Amal Hajjaj
The objective of this thesis is to present a theoretical and experimental investigation of the dynamics of micro and nano-electromechanical systems electrothermally tuned and electrostatically actuated, and explore their potential for practical applications. The first part of the dissertation presents the tuning of the frequency of clamped-clamped micro and nano-resonators, straight and curved. These resonators are electrothermally or electrostatically tuned. The effect of geometric parameters on the frequency variation is investigated experimentally and theoretically using...

High Performance Polar Decomposition on Manycore Systems and its application to Symmetric Eigensolvers and the Singular Value Decomposition

Dalal Sukkari
The Polar Decomposition (PD) of a dense matrix is an important operation in linear algebra, while being a building block for solving the Symmetric Eigenvalue Problem (SEP) and computing the Singular Value Decomposition (SVD). It can be directly calculated through the SVD itself, or iteratively using the QR Dynamically-Weighted Halley (QDWH) algorithm. The former is difficult to parallelize due to the preponderant number of memory-bound operations during the bidiagonal reduction. The latter is an iterative...

Applications in computational structural biology: the generation of a protein modelling pipeline and the structural analysis of patient-derived mutations

Francisco J. Guzmán-Vega
Besides helping us advance the understanding of the physicochemical principles governing the three-dimensional folding of proteins and their mechanisms of action, the ability to build, evaluate, and optimize reliable 3D protein models has provided valuable tools for the development of different applications in the fields of biotechnology, medicine, and synthetic biology. The development of automated algorithms has made many of the current methodologies for protein modelling and visualization available to researchers from all backgrounds, without...

Modular Autonomous Taxiing Simulation and 3D Siamese Vehicle Tracking

Jesus Alejandro Zarzar Torano
The automation of navigation for different kinds of vehicles is a research problem of great interest. This problem has applications with unmanned aerial vehicles (UAVs) as well as manned vehicles such as cars and planes. The goal of an autonomous vehicle is to navigate safely from one point to another given a set of high-level instructions and data from a set of sensors. This thesis explores an implementation of a modular approach for autonomously driving...

Wavelength Dependence of Underwater Turbulence Characterized Using Laser-Based White Light

Omar Alkhazragi
The means of communication in oceanic environments is currently dominated by sonar. Although it is reliable for long-distance transmission, the vision of internet of underwater things (IoUT) requires an alternate means for high-data-rate transmission. It is also envisaged that a networked underwater and above-water objects, such as sensor nodes, and autonomous underwater vehicles will benefit seafloor exploration. The use of laser-based optical communication is poised to realize this dream while working hand-in-hand with acoustic and...

Standardized short-term bleaching assays resolve differences in coral thermotolerance across microhabitat reef sites

Gabriela Perna
Coral bleaching is now the main driver of reef degradation. The common notion is that most corals bleach and suffer mortality at just 1-2°C above their mean summer maximum temperatures, but some species and genotypes resist or recover better than others. Here we conducted a series of 18-hour short-term heat stress assays side-by-side with a long-term heat stress experiment to assess the ability of both approaches to resolve putative differences in coral thermotolerance and provide...

Development of State-Of-The-Art Interfacially Polymerized Defect-Free Thin-Film Composite Membranes for Gas- and Liquid Separations

Zain Ali
This research was undertaken to develop state-of-the-art interfacially polymerized (IP) defect-free thin-film composite (TFC) membranes and understand their structure-function-performance relationships. Recent research showed the presence of defects in interfacially polymerized commercial membranes which potentially deter performance in liquid separations and render the membranes inadequate for gas separations. Firstly, a modified method (named KRO1) was developed to fabricate interfacially polymerized defect-free TFCs using m-phenylene diamine (MPD) and trimesoyl chloride (TMC). The systematic study revealed the ability...

A single molecule view of FEN1 remarkable substrate recognition, perfect catalysis and regulation

Manal Zaher
DNA replication is one of the most fundamental processes in all living organisms. Its semi-discontinuous nature dictates that the lagging strand is synthesized in short fragments called Okazaki fragments. In eukaryotes, each Okazaki fragment is initiated by an ~ 30-40 nucleotide-long RNA-DNA hybrid primer that is synthesized by Pol α-primase complex. To ensure genomic stability, the RNA primer has to be excised, any misincorporations by Pol α have to be corrected for and finally the...

Non-equilibrium transport in topologically non-trivial systems

Sumit Ghosh
One of the most remarkable achievements of modern condensed matter physics is the discovery of topological phases of matter. Materials in a non-trivial topological phase or the topological insulators can be distinguished by their unique electronic and transport properties which are indifferent to different types of perturbations and thus open new routes towards the dissipationless transport. Explaining their properties requires proper involvement of relativistic approach as well as topological analysis. Among different classes of topological...

Robust Estimation of Scatter Matrix, Random Matrix Theory and an Application to Spectrum Sensing

Zhedong Liu
The covariance estimation is one of the most critical tasks in multivariate statistical analysis. In many applications, reliable estimation of the covariance matrix, or scatter matrix in general, is required. The performance of the classical maximum likelihood method relies a great deal on the validity of the model assumption. Since the assumptions are often approximately correct, many robust statistical methods have been proposed to be robust against the deviation from the model assumptions. M-estimator is...

Characterization of microbiologically influenced corrosion in pipelines by using metagenomics

Badoor Nasser
Corrosion in pipelines and reservoir tanks in oil plants is a serious problem in the energy industries around the world because it causes a huge economic loss due to not only frequent replacements of the parts of pipelines and tanks but also potential damage of the entire fields of crude oil. Previous studies have revealed that corrosions are generated mainly by microbial activities and they are now called as Microbial Influenced Corrosion (MIC) or simply...

Variations in reef-associated fish communities in response to different benthic states in the east central Red Sea

George Short
Coral reefs are priority habitats which are vulnerable to natural and anthropogenic disturbances. These can cause phase shifts from coral habitat to degraded algal-dominated states – and consequent changes in the distribution, abundance and activity of associated fish species. In the eastern Red Sea, human-induced reef degradation is likely to increase with planned development of the Saudi Arabian coast and the changing climate. The present study therefore investigates the ecological effects of coral-algal phase shifts...

Random Matrix Theory: Selected Applications from Statistical Signal Processing and Machine Learning

Khalil Elkhalil
Random matrix theory is an outstanding mathematical tool that has demonstrated its usefulness in many areas ranging from wireless communication to finance and economics. The main motivation behind its use comes from the fundamental role that random matrices play in modeling unknown and unpredictable physical quantities. In many situations, meaningful metrics expressed as scalar functionals of these random matrices arise naturally. Along this line, the present work consists in leveraging tools from random matrix theory...

Evaluating the regulation of signaling pathways downstream of CD44 antibody treatment in AML

Arwa Alghuneim
Acute myeloid leukemia (AML) is a subset of leukemia that is characterized by the clonal expansion of cytogenetically and molecularly abnormal myeloid blasts. These blasts are highly proliferative accumulating in bone marrow and blood which leads to severe infections, anemia, and bone marrow failure. The poor prognosis of AML patients caused by the low tolerance to intensive chemotherapy has encouraged the pursuit of alternative therapeutic approaches. Differentiation therapy which involves the use of agents that...

On the Lp-Integrability of Green’s function for Elliptic Operators

Abdulrahman Alharbi
In this thesis, we discuss some of the results that were proven by Fabes and Stroock in 1984. Our main purpose is to give a self-contained presentation of the proof of this results. The first result is on the existence of a “reverse H ̈older inequality” for the Green’s function. We utilize the work of Muckenhoupt on the reverse Ho ̈lder inequality and its connection to the A∞ class to establish a comparability property for...

New Approaches in Bayesian Estimation of Earthquake Fault Model Parameters from InSAR and GPS

Rishabh Dutta
InSAR and GPS observations of Earth’s surface displacements are used to infer earthquake source parameters. Bayesian estimation of the source parameters produces the probability densities of the plausible parameters that are consistent with the observations. This facilitates analysis of the model parameters uncertainties and trade-offs regardless of the complexities (e.g., non-linearity, non-uniqueness, under- or over- parametrization, etc.) of the problem. In this thesis, I show various approaches, e.g., use of a priori information and innovative...

Registration Year

  • 2019
    236

Resource Types

  • Dissertation
    227
  • Dataset
    7
  • Software
    2

Affiliations

  • King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
    230
  • King Abdullah University of Science and Technology
    6
  • Stanford University
    2
  • International Centre for Genetic Engineering and Biotechnology
    2
  • University of California, Santa Cruz
    2
  • Southern Cross University
    1
  • Great Barrier Reef Marine Park Authority
    1
  • University of Cambridge
    1
  • Austral University of Chile
    1
  • Curtin University
    1