240 Works

Highly efficient photoleletrochemical water splitting by optical, electrical and catalysis concurrent management

Hui-Chun Fu
One way of harnessing and storing our most abundant and renewable energy source, sunlight, is by utilizing it to split water for the hydrogen generation as a storable form of fuel. Si, the most investigated material for solar-to-hydrogen technology has great potential as the single photoelectrode. While some success has been achieved in Si-Based photoelectrochemical (PEC) systems, they suffer from low efficiency and short longevity. Moreover, in order for hydrogen to be commercially viable, the...

Algorithms and Frameworks for Graph Analytics at Scale

Fuad Tarek Jamour
Graph queries typically involve retrieving entities with certain properties and connectivity patterns. One popular property is betweenness centrality, which is a quantitative measure of importance used in many applications such as identifying influential users in social networks. Solving graph queries that involve retrieving important entities with user-defined connectivity patterns in large graphs requires efficient com- putation of betweenness centrality and efficient graph query engines. The first part of this thesis studies the betweenness centrality problem,...

Sim-to-Real Transfer for Autonomous Navigation

Matthias Müller
This work investigates the problem of transfer from simulation to the real world in the context of autonomous navigation. To this end, we first present a photo-realistic training and evaluation simulator (Sim4CV)* which enables several applications across various fields of computer vision. Built on top of the Unreal Engine, the simulator features cars and unmanned aerial vehicles (UAVs) with a realistic physics simulation and diverse urban and suburban 3D environments. We demonstrate the versatility of...

VCC-LF dataset

Rui Li & Wolfgang Heidrich
This is readme for VCC-LF dataset. This dataset provides light field mat files that capture by Lytro I. The light field resolusion is [h,w,u,v,d]. If you use these data or our toolkit code, please cite our paper properly @inproceedings{ lirsiggraphasia2019, title={Hierarchical and View-invariant Light Field Segmentation by Maximizing Entropy Rate on 4D Ray Graphs}, author={Li, Rui and Heidrich, Wolfgang}, booktitle={ACM Transactions on Graphics (Proc. SIGGRAPH Asia)}, year={2019}, publisher={ACM} }

Characterization of a Novel Nuclear Specific Dicer-isoform in Human Cells

Fatema H. Alquraish
For more than a decade, studies focused on RNA interference (RNAi) pathway as a pivotal gene regulatory mechanism. RNAi components are attracting considerable interest due to the recent evidence demonstrating that they play a role not only in post-transcriptional regulation but also in transcriptional level. The involvement of RNAi components in heterochromatin formation and RNA Pol II processivity and alternative splicing in different organisms has been shown. Dicer protein, a highly conserved protein among kingdoms,...

Analyzing and Manipulating Wave Propagation in Complex Structures

Rasha Al Jahdali
The focus of this dissertation is analyzing and manipulating acoustic wave propagation in metamaterials, which can be used to assist the design of acoustic devices. Metamaterials are artificial materials, which are arranged in certain patterns at a scale smaller than the wavelength and can exhibit properties beyond those naturally occurring materials. With metamaterials, novel phenomena, such as focusing, super absorption, cloaking and localization of ultrasound, are theoretically proposed and experimentally verified. In recent years, a...

Code for \"DDR: a method to predict drug target interactions using multiple similarities\"

Rawan S. Olayan, Haitham Ashoor & Vladimir B. Bajic
Motivation: Finding computationally drug-target interactions (DTIs) is a convenient strategy to identify new DTIs at low cost with reasonable accuracy. However, the current DTI prediction methods suffer a high false-positive prediction rate. Results: We developed DDR, a novel method that improves the DTI prediction accuracy. DDR is based on the use of a heterogeneous graph that contains known DTIs with multiple similarities between drugs and multiple similarities between target proteins. DDR applies non-linear similarity fusion...

Toward selective H2 evolution from overall water splitting and the trifluoromethylation of heteroarenes via heterogeneous photocatalysis

Muhammad Qureshi
Converting solar energy into useful chemical bonds via photocatalysis is a growing field aimed at addressing global challenges. The research disclosed describes heterogeneous photocatalysis as a nanophotoelectrochemical cell as photocatalysts enable both reduction and oxidation reactions using the local charge separation of photo-excited carriers. Herein, experimental and theoretical results of nanoscale electrolysis of water on the surface of CrOx/Pt/SrTiO3 showed that ohmic losses are negligible when the anode and cathode are within nanometer distances from...

A Computational Investigation of Multiple Injection Strategy in an Isobaric Combustion Engine

Hammam H. Aljabri
Abstract: This thesis aims to contribute to the development of the isobaric combustion engines by exploring multiple injection strategies, by means of computational simulations using a commercial software Converge. A single injection case validated with experimental data in terms pressure trace and heat release rate was used as a baseline reference. The adjustment of the turbulent kinetic energy dissipation constant is found to have the most significant influence in reproducing the pressure and heat release...

‘Allelofertile’ soil islands self-conditioned by Welwitschia mirabilis in the Namib Desert

Dalia H. Shabaan
Under the extreme arid conditions of deserts, long periods of drought, nutrient-poor soils and high temperatures severely challenge the primary productivity of the ecosystem. Desert plants have evolved morphological and physiological adaptations against abiotic stresses. Along with these adaptation strategies they can recondition their surrounding soil, which will result in the enrichment of nutrients and moisture in the soil surrounding the plant. Although such self-fertilization may support the growth of other sympatric plant species under...

Traffic Monitoring and MAC-Layer Design for Future IoT Systems

Enas M. Odat
The advances in the technology and the emergence of low complexity intelligent devices result in the evolution of the Internet-of-Things (IoT). In most IoT application scenarios, billions of things are interconnected together using standard communication protocols to provide services for different applications in the healthcare industry, smart cities, transportation, and food supply chain. Despite their advantage of connecting things anywhere, anytime, and anyplace, IoT presents many challenges due to the heterogeneity, density, the power constraints...

Towards Multistate Magnetic Tunnel Junctions for Memory and Logic Applications

Ulan Myrzakhan
For many decades, the revolution in semiconductor industry has continuously been powered by the successful down scaling of complementary metal-oxide semiconductor (CMOS) technology to produce integrated circuits with improved performance at lower cost. However, current charge-based CMOS technology is already approaching physical limits and, thus, encounters a number of technological challenges. Spintronics is an emerging and rapidly evolving research field that has a great potential to overcome these challenges confronting CMOS by introducing the electron...

Object Detection Using Multiple Level Annotations

Mengmeng Xu
Object detection is a fundamental problem in computer vision. Impressive results have been achieved on large-scale detection benchmarks by fully-supervised object detection (FSOD) methods. However, FSOD approaches require tremendous instance-level annotations, which are time-consuming to collect. In contrast, weakly supervised object detection (WSOD) exploits easily-collected image-level labels while it suffers from relatively inferior detection performance. This thesis studies hybrid learning methods on the object detection problems. We intend to train an object detector from a...

Investigation of Zinc Interactions to Human Serum Albumin and Their Modulation by Fatty Acids

Samah Al-Harthi
Zinc is an essential metal ion for the activity of multiple enzymes and transcription factors. Among many other transporting proteins human serum albumin (HSA) is the main carrier of Zn(II) in the blood plasma. HSA displays multiple ligand binding sites with extraordinary binding capacity for a wide range of ions and molecules including fatty acids. Hence, HSA controls the availability and distribution of those molecules throughout the body. Previous studies have established that the existence...

Application of Quantitative Phosphoproteomics to the Study of Cnidarian-Dinoflagellate Symbiosis

Fabia Simona
Corals are cnidarian animals that build the founding structures of tropical reefs, which survival depends upon the obligate symbiotic association to photosynthetic dinoflagellate algae in the family Symbiodiniaceae. As corals are facing increasing environmental and anthropogenic stress, understanding the molecular principles governing this unique symbiotic association is crucial to predict their adaptive potential. Due to logistic, costly, and experimental difficulties of working with corals, we use the sea anemone Aiptasia (sensu Exaiptasia pallida) as a...

Semantic Prioritization of Novel Causative Genomic Variants in Mendelian and Oligogenic Diseases

Imene Boudellioua
Recent advances in Next Generation Sequencing (NGS) technologies have facilitated the generation of massive amounts of genomic data which in turn is bringing the promise that personalized medicine will soon become widely available. As a result, there is an increasing pressure to develop computational tools to analyze and interpret genomic data. In this dissertation, we present a systematic approach for interrogating patients’ genomes to identify candidate causal genomic variants of Mendelian and oligogenic diseases. To...

Expression of EZH1-Polycomb Repressive Complex 2 and MALAT1 lncRNA and their Combined Role in Epigenetic Adaptive Response

Lamya Al Fuhaid
Living cells maintain stable transcriptional programs while exhibiting plasticity that allows them to respond to environmental stimuli. The Polycomb repressive complex 2 (PRC2) is a key regulator of chromatin structure that maintains gene silencing through the methylation of histone H3 on lysine 27 (H3K27me), establishing chromatin-based memory. Two variants of PRC2 are present in mammalian cells, PRC2-EZH2 which is predominantly present in differentiating cells, and PRC2-EZH1 that predominates in post-mitotic tissues. PRC2-EZH1α/β pathway is involved...

Leader-Follower Approach with an On-board Localization Scheme for Underwater Swarm Applications

Sarah Toonsi
A striking feature of swarm robotics is its ability to solve complex tasks through simple local interactions between robots. Those interactions require a good infrastructure in communication and localization. However, in underwater environments, the severe attenuation of radio waves complicates communication and localization of different vehicles. Existing literature on underwater swarms use centralized network topology which require physical vicinity to the central node to ensure reliability. We are interested in building a decentralized underwater swarm...

The role of NAC transcription factors in responses of plants to heat and salt stresses

Nouf Owdah Hameed Alshareef
Soil salinity and heat stress are two major abiotic stresses affecting plant growth and yield. Transcription factors (TFs) are key regulators in stress responses. They link stress sensing with many tolerance mechanisms by translating stress signals into changes in gene expression that ultimately contribute to stress tolerance. The NAC (NAM, ATAF and CUC) TF family have been found to be involved in responses to biotic and abiotic stresses. In this PhD project, the role of...

Arrival-time picking methodology using fuzzy c-means and Akaike information criterion for downhole microseismic data

Eduardo Valero Cano
Microseismic monitoring is a valuable technique to locate and characterize frac- tures in unconventional reservoirs. The monitoring is usually carried out from a large surface array of vertical-component receivers or a short downhole array of three- component receivers. For a downhole array, P- and S-wave arrival-time picking is typically required to process the microseismic data. Furthermore, arrival-time pick- ing is done automatically considering the large volumes of microseismic data. In this work, I propose a...

Biofouling in anaerobic membrane bioreactors: To control or not to?

Hong Cheng
Anaerobic membrane bioreactor (AnMBR) serves as a more sustainable form of wastewater treatment. However, biofouling is particularly detrimental to the performanceof AnMBRs. This dissertation focuses on understanding more about the biofouling in nMBR, and to devise strategies to control or make use of these biofoulant layers. First, we aim to investigate the microbial community structure of sludge and biofilm from 13 different AnMBRs. Our findings indicate 20 sludge core genera and 12 biofilm core genera...

Short-read Chromosome Level Genome Assembly of Digitaria exilis

Liubov Gapa
Genomics has become an important tool in agriculture. Many modern crop breeding approaches such as genomic selection and genome editing require detailed information of the genomic composition of a crop species. However, the assembly of high-quality genome sequences is prone to technical artifacts that arise from inaccuracies in the sequencing technology and assembly algorithms. This is particularly true for the genomes of cereal crops, which are often very large, repeat-rich, and polyploid. Until recently, the...

Synthesis, Characterization and Reactivity of Manganese PN3 Pincer Complexes

Razan Mal
Manganese is amongst the most abundant transition metals on earth. Playing several roles in enzymatic function, manganese is largely considered biocompatible and, in comparison to most transition metals, it is relatively inexpensive. It is surprising then, that manganese remains poorly explored in the field of pincer-based homogenous catalysis. PN3(P) pincer ligands have proved to impart different kinetic and thermodynamic properties to the complexes they are a part of when compared to analogous complexes of ligands...

Multiscale Hybridization towards Efficient Oil and Gas Flows Simulations within Fractured Rocks

Sahar Amir
Fractures impact the geological systems remarkably. So, their effects are included within the mathematical simulation models. Literature simulation schemes either lose the facture characteristics or are effort and time-consuming. So Hybrid-Fracture schemes are developed to overcome these drawbacks. In the dissertation, a generalized Hybrid-Embedded Fractures (HEF) scheme is developed. It establishes a hierarchical classification based on fracture length's relation to uniform grid-cell lengths. Tall and medium-length fractures are detected from images, classified using Machine-Learning (ML)...

Seawater-induced Biofouling in Direct Contact Membrane Distillation

Sarah A. Alsaidalani
Membrane distillation (MD) is a promising desalination technology which allows to achieve high salt rejection at low energy expenses as compared to conventional desalination processes. However, just like in any other membrane separation process, the MD membrane is susceptible to biofouling which is one of the critical problems in membrane-based systems. In this study, we investigated the effects of spacer design and feed temperature on the biofilm formation and proliferation in a flat-sheet direct contact...

Registration Year

  • 2019

Resource Types

  • Dissertation
  • Dataset
  • Software
  • Other


  • King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia