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Articles 57511 - 57540 of 197988

Full-Text Articles in Engineering

Query Rewriting With Thesaurus-Based For Handling Semantic Heterogeneity In Database Integration, I Made Riyan Adi Nugroho, I Wayan Budi Sentana Jul 2020

Query Rewriting With Thesaurus-Based For Handling Semantic Heterogeneity In Database Integration, I Made Riyan Adi Nugroho, I Wayan Budi Sentana

Knowledge Engineering and Data Science

Nowadays, studies on handling semantic heterogeneity still become a challenge for researcher. Several methods have been used to solve these problems, one of which is query rewriting, implemented by rewriting a query into the latest one by using the selected schema. Semantic query rewriting needs a framework in order to identify the connection through the data schema sources. This line is used as a basis for scheme selection. Also, ontology is a model which often be used in these specific cases. The lack of ontology becomes a significant problem that usually seen. Therefore, this paper will describe an alternative framework …

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Human Intestinal Condition Identification Based-On Blended Spatial And Morphological Feature Using Artificial Neural Network Classifier, Ummi Athiyah, Arif Wirawan Muhammad, Ahmad Azhari Jul 2020

Human Intestinal Condition Identification Based-On Blended Spatial And Morphological Feature Using Artificial Neural Network Classifier, Ummi Athiyah, Arif Wirawan Muhammad, Ahmad Azhari

Knowledge Engineering and Data Science

Colon cancer is a type of disease that attacks the intestinal walls cell of humans. Colorectal endoscopic screening technique is a common step carried out by the health expert/gynecologist to determine the condition of the human intestine. Manual interpretation requires quite a long time to reach a result. Along with the development of increasingly advanced digital computing techniques, then some of the weaknesses of the manually endoscopic image interpretation analysis model can be corrected by automating the detection process of the presence or absence of cancerous cells in the gut. Identification of human intestinal conditions using an artificial neural network …

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Parallelization Of Partitioning Around Medoids (Pam) In K-Medoids Clustering On Gpu, Adhi Prahara, Dewi Pramudi Ismi, Ahmad Azhari Jul 2020

Parallelization Of Partitioning Around Medoids (Pam) In K-Medoids Clustering On Gpu, Adhi Prahara, Dewi Pramudi Ismi, Ahmad Azhari

Knowledge Engineering and Data Science

K-medoids clustering is categorized as partitional clustering. K-medoids offers better result when dealing with outliers and arbitrary distance metric also in the situation when the mean or median does not exist within data. However, k-medoids suffers a high computational complexity. Partitioning Around Medoids (PAM) has been developed to improve k-medoids clustering, consists of build and swap steps and uses the entire dataset to find the best potential medoids. Thus, PAM produces better medoids than other algorithms. This research proposes the parallelization of PAM in k-medoids clustering on GPU to reduce computational time at the swap step of PAM. The parallelization …

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Dynamics Of Discontinuities In Elastic Solids, Arkadi Berezovski, Mihhail Berezovski Jul 2020

Dynamics Of Discontinuities In Elastic Solids, Arkadi Berezovski, Mihhail Berezovski

Publications

The paper is devoted to evolving discontinuities in elastic solids. A discontinuity is represented as a singular set of material points. Evolution of a discontinuity is driven by the configurational force acting at such a set. The main attention is paid to the determination of the velocity of a propagating discontinuity. Martensitic phase transition fronts and brittle cracks are considered as representative examples.

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Feature Bagging And Extreme Learning Machines: Machine Learning With Severe Memory Constraints, Kallin Khan, Edward Ratner, Robert Ludwig, Amaury Lendasse Jul 2020

Feature Bagging And Extreme Learning Machines: Machine Learning With Severe Memory Constraints, Kallin Khan, Edward Ratner, Robert Ludwig, Amaury Lendasse

Engineering Management and Systems Engineering Faculty Research & Creative Works

With the Onset of Easy Access to Supercomputers with High Amounts of Memory Available, Machine Learning Algorithms Have Continued to Increase the Resources Necessary to Perform their Data Analysis. This Paper Aims to Show Development in the Other Direction, by Showing that through the Use of a Combination of Feature Bagging and Ensembles of Extreme Learning Machines (Elms) It is Possible to Leverage Machine Learning, Without Loss of Accuracy, on Devices Where Flash Memory is Very Scarce, and Random-Access Memory (Ram) is Even Scarcer, Such as on Embedded Systems. This Novel Strategy is Called Feature Bagged Extreme Learning Machines (Fb-Elms).

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Effect Of Rf Signals On Tvs Diode Trigger Voltage For Esd Protection, Giorgi Maghlakelidze, Shubhankar Marathe, Wei Huang, Joost Willemen, David Pommerenke Jul 2020

Effect Of Rf Signals On Tvs Diode Trigger Voltage For Esd Protection, Giorgi Maghlakelidze, Shubhankar Marathe, Wei Huang, Joost Willemen, David Pommerenke

Electrical and Computer Engineering Faculty Research & Creative Works

Discrete transient voltage suppressor devices are used in addition to the on-chip ESD protection to protect the ICs from ESD damage. In applications involving snapback TVS devices, the trigger voltage is selected to be higher than the desired signals on the net. The presence of RF on the net affects the TVS behavior, even if the RF levels are less than the snapback trigger voltage. Known effects are RF intermodulation and harmonic generation, which diminish SNR. This work describes the other effect on the TVS diodes - the observed reduction of the snapback trigger voltage, monotonically dependent on the amplitude …

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The Effect Of The Parallel-Plate Mode On Striplines In Inhomogeneous Dielectric Media, Jiayi He, Shaohui Yong, Zurab Kiguradze, Arun Chada, Bhyrav Mutnury, James Drewniak Jul 2020

The Effect Of The Parallel-Plate Mode On Striplines In Inhomogeneous Dielectric Media, Jiayi He, Shaohui Yong, Zurab Kiguradze, Arun Chada, Bhyrav Mutnury, James Drewniak

Electrical and Computer Engineering Faculty Research & Creative Works

Strip lines are widely used in high speed printed circuit boards (PCB). When the strip line is in inhomogeneous dielectric media, its principal operation mode is quasi-TEM. In this case, the parallel-plate mode between two ground planes can be excited as a parasitic mode. This paper investigates the effect of this parasitic mode on strip lines through simulations. The simulated S-parameters of strip lines when this parallel-plate mode is excited and suppressed are compared. The measured S-parameters of strip lines with and without the ground stitching vias are also compared. The impact of the parasitic mode on time domain crosstalk …

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A Study Of Coverlay Coated Microstrip Lines For Crosstalk Reduction In Ddr5, Qiang Ming Cai, Yuyu Zhu, Runren Zhang, Yinglei Ren, Xiaoning Ye, Jun Fan Jul 2020

A Study Of Coverlay Coated Microstrip Lines For Crosstalk Reduction In Ddr5, Qiang Ming Cai, Yuyu Zhu, Runren Zhang, Yinglei Ren, Xiaoning Ye, Jun Fan

Electrical and Computer Engineering Faculty Research & Creative Works

Crosstalk becomes a serious problem in microstrip design of printed circuit boards (PCBs) in DDR5. In high-density and high-speed PCBs, widening space or putting shielding between traces to mitigate crosstalk noise may become less effective, because of the limited space. This paper presents a simple and efficient crosstalk reduction approach by using coverlay coated microstrip lines. This coverlay is available in a variety of film and adhesive thicknesses, which is commonly used materials for the resistance welding transform in PCB production. Based on the simulated S-parameters, the FEXT keeps under -40 dB from dc to 16.0 GHz, and more than …

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Low Emf Design Of Cochlear Implant Wireless Power Transfer System Using A Shielding Coil, Seokwoo Hong, Seungtaek Jeong, Seongsoo Lee, Boogyo Sim, Hongseok Kim, Joungho Kim Jul 2020

Low Emf Design Of Cochlear Implant Wireless Power Transfer System Using A Shielding Coil, Seokwoo Hong, Seungtaek Jeong, Seongsoo Lee, Boogyo Sim, Hongseok Kim, Joungho Kim

Electrical and Computer Engineering Faculty Research & Creative Works

Wireless power transfer (WPT) technology is widely used for various applications because of convenience and safety. Especially, medical implant devices such as a cochlear implant are one of the typical applications of the WPT technology. However, WPT systems have problems with electromagnetic field (EMF) leakage, which can cause electro-magnetic interference (EMI) issues in the human body. In this paper, we propose an additional shielding coil for the effective suppression of EMF radiation of a WPT system. The proposed method reduces the EMF leakage in operating frequency range. We verified that the proposed shielding coil reduced the EMF leakage by 5.1 …

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Sensitivity Analysis Of Local Soldermask And Coverlay In High Speed Transimission Lines For Ddr5 Applications To Reduce Fext, Zhu Lin, Xin Cao, Qiang Ming Cai, Yinglei Ren, Xiaoning Ye, Jun Fan Jul 2020

Sensitivity Analysis Of Local Soldermask And Coverlay In High Speed Transimission Lines For Ddr5 Applications To Reduce Fext, Zhu Lin, Xin Cao, Qiang Ming Cai, Yinglei Ren, Xiaoning Ye, Jun Fan

Electrical and Computer Engineering Faculty Research & Creative Works

This article investigated the effects of local solder-mask and overlay structure changes on crosstalk. This structure is based on a four-layer high-speed PCB on a computer DDR5 board. Our goal is to use the obtained simulation results to locate the optimal response that not only meets the performance requirements but is also robust to geometric changes caused by manufacturing tolerances. These two methods have a good correlation with the simulation results and show strong capabilities in the practical applications.

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High-Speed Channel Equalization Applying Parallel Bayesian Machine Learning, Zurab Kiguradze, Nana Dikhaminjia, Mikheil Tsiklauri, Jiayi He, Bhyrav Mutnury, Arun Chada, James L. Drewniak Jul 2020

High-Speed Channel Equalization Applying Parallel Bayesian Machine Learning, Zurab Kiguradze, Nana Dikhaminjia, Mikheil Tsiklauri, Jiayi He, Bhyrav Mutnury, Arun Chada, James L. Drewniak

Electrical and Computer Engineering Faculty Research & Creative Works

Recovering attenuated signals caused by different issues including connections between connectors and chips of the devices, channel loss, and crosstalk is a challenging problem. Equalization is the most popular way to restore distorted signals. Different optimization algorithms are used to find the best tap coefficients for each equalization that improves eye opening and decreases the bit error rate (BER). Nowadays algorithms of equalization mainly operate to reduce the difference between input and output signals. In turn, this will increase eye height indirectly, but direct maximization of the eye height will restore the signal even better. The paper proposes a new …

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Rfi Estimation For Multiple Noise Sources Due To Modulation At A Digital Mic Using Diople Moment Based Reciprocity, Shengxuan Xia, Jingdong Sun, Qiaolei Huang, Yansheng Wang, Hanfeng Wang, Ken Wu, Songping Wu, Jun Fan Jul 2020

Rfi Estimation For Multiple Noise Sources Due To Modulation At A Digital Mic Using Diople Moment Based Reciprocity, Shengxuan Xia, Jingdong Sun, Qiaolei Huang, Yansheng Wang, Hanfeng Wang, Ken Wu, Songping Wu, Jun Fan

Electrical and Computer Engineering Faculty Research & Creative Works

Non-ideal ground structures in flexible printed circuit board, such as the meshed ground or discrete ground nets, can cause severe RFI to the nearby antennas. Those RF radiators can be modeled as a set of equivalent dipole moment(s) when they are electrically small. Then, the dipole moment-based reciprocity theorem can be applied to estimate the noise coupling level. In this article, a practical methodology using the dipole moment-based reciprocity is proposed to identify multiple radiation sources of a real cellphone product. Multiple equivalent dipole moments are constructed with one-to-one correspondence to the physical structures. The reciprocity calculations can eventually provide …

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Fabrication And Characterization Of Flexible Three-Phase Zno-Graphene-Epoxy Electro-Active Thin-Film Nanocomposites: Towards Applications In Wearable Biomedical Devices, Mandeep Singh, Sanjeev Kumar, Shervin Zoghi, Debaki Sarcar, Saquib Ahmed, Shaestagir Chowdhury, Sankha Banerjee Jul 2020

Fabrication And Characterization Of Flexible Three-Phase Zno-Graphene-Epoxy Electro-Active Thin-Film Nanocomposites: Towards Applications In Wearable Biomedical Devices, Mandeep Singh, Sanjeev Kumar, Shervin Zoghi, Debaki Sarcar, Saquib Ahmed, Shaestagir Chowdhury, Sankha Banerjee

Mechanical and Materials Engineering Faculty Publications and Presentations

Perovskite oxides have been used as sensors, actuators, transducers, for sound generation and detection, and also in optical instruments and microscopes. Perovskite halides are currently considered as optoelectronic devices such as solar cells, photodetectors, and radiation detection, but there are major issues with stability, interfacial recombination, and electron/hole mobility. The following work looks into the fabrication of non-toxic ZnO-based lead-free alternatives to perovskite oxides for use as secondary sensors or electron transport layers along with perovskite halides for application in stacked biomedical wearable devices. Three-phase, lead-free, Zinc Oxide-Graphene-Epoxy electroactive nanocomposite thin films were fabricated. The volume fraction of the Graphene …

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Experience Of Teaching Introduction To Electrical Engineering With An Online Platform, Junfei Li, Jaime Ramos-Salas, Cara Li Jul 2020

Experience Of Teaching Introduction To Electrical Engineering With An Online Platform, Junfei Li, Jaime Ramos-Salas, Cara Li

Electrical and Computer Engineering Faculty Publications

To engage engineering students in their field of studies, it is essential for the students to take major courses as early as possible. However, first year EE major students in our institution don’t have many options as almost all major courses need physics and math courses as prerequisites. For most of our students, the Introduction to Electrical Engineering is available to them as the only Electrical Engineering course during their first semester in college. It is offered to introduce the students to such topics as electrical circuits, digital logic, and robotics. In addition to learning fundamental topics, the students are …

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A Study Of The Thermodynamics Of Small Systems And Phase Transition In Bulk Square Well-Hard Disk Binary Mixture, Gulce Kalyoncu Jul 2020

A Study Of The Thermodynamics Of Small Systems And Phase Transition In Bulk Square Well-Hard Disk Binary Mixture, Gulce Kalyoncu

Graduate Theses and Dissertations

Under the umbrella of statistical mechanics and particle-based simulations, two distinct problems have been discussed in this study. The first part included systems of finite clusters of three and 13 particles, where the particles are interacting via Lennard Jones potential. A machine learning technique, Diffusion Maps (DMap), has been employed to the large datasets of thermodynamically small systems from Monte Carlo simulations in order to identify the structural and energetic changes in these systems. DMap suggests at most three dimensions are required to describe and identify the systems with 9 (N = 3) and 39 (N = 13) dimensions. At …

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Towards A Cyber-Physical Manufacturing Cloud Through Operable Digital Twins And Virtual Production Lines, Md Rakib Shahriar Jul 2020

Towards A Cyber-Physical Manufacturing Cloud Through Operable Digital Twins And Virtual Production Lines, Md Rakib Shahriar

Graduate Theses and Dissertations

In last decade, the paradigm of Cyber-Physical Systems (CPS) has integrated industrial manufacturing systems with Cloud Computing technologies for Cloud Manufacturing. Up to 2015, there were many CPS-based manufacturing systems that collected real-time machining data to perform remote monitoring, prognostics and health management, and predictive maintenance. However, these CPS-integrated and network ready machines were not directly connected to the elements of Cloud Manufacturing and required human-in-the-loop. Addressing this gap, we introduced a new paradigm of Cyber-Physical Manufacturing Cloud (CPMC) that bridges a gap between physical machines and virtual space in 2017. CPMC virtualizes machine tools in cloud through web services …

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Synthesis And Application Of Ceramic Paste For High-Temperature Electronic Packaging, Ardalan Nasiri Jul 2020

Synthesis And Application Of Ceramic Paste For High-Temperature Electronic Packaging, Ardalan Nasiri

Graduate Theses and Dissertations

This dissertation research focused on the synthesis and application of ceramic paste for high-temperature applications. An alumina paste material comprising aluminum dihydric phosphate and alumina powder was developed for high-temperature electronic packaging. Nano aluminum nitride and nano-silica powders were embedded to promote the paste curing process, limit the grain growth, and increase its bond shear strength. The chip-to-substrate bond strength was enhanced and met the MIL-STD requirements for die-attach assembly. Its encapsulation property was improved with fewer cracks compared to similar commercial ceramic encapsulants. The die-attach material and encapsulation properties tested at 500°C showed no defect or additional cracks. Thermal …

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Converter- And Module-Level Packaging For High Power Density And High Efficiency Power Conversion, Amol Rajendrakumar Deshpande Jul 2020

Converter- And Module-Level Packaging For High Power Density And High Efficiency Power Conversion, Amol Rajendrakumar Deshpande

Graduate Theses and Dissertations

Advancements in the converter- and module-level packaging will be the key for the development of the emerging high-power, high power-density, high-eciency power conversion applications, such as traction, shipboards, more-electric-aircraft, and locomotive. Wide bandgap (WBG) devices such as silicon carbide (SiC) MOSFET attract much attention in these applications for their fast switching speeds, resulting in low loss and a consequent possibility for high switching frequency to increase the power density. However, for high-current, high power implementations, WBG devices are still available in small die sizes. Multiple SiC devices need to be connected in parallel to replace a large IGBT die. It …

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Design And Optimization Of Multichip Gan Module Enabling Improved Switching Performance, Asif Imran Emon Jul 2020

Design And Optimization Of Multichip Gan Module Enabling Improved Switching Performance, Asif Imran Emon

Graduate Theses and Dissertations

Wide bandgap semiconductors (SiC & GaN) due to their enhanced performance and superior material properties compared to traditional silicon power devices have become the ultimate choice for future high-performance power electronics energy conversion. GaN high electron mobility transistor (HEMT) offers very fast switching capability enabling the designer to push switching frequency to the MHz range. Traditional device packaging becomes a limiting factor in fully harnessing the benefits offered by these advanced power devices, and thus, improved and advanced packaging structures are a must to bridge the gap between GaN devices and their applications. A co-design, co-optimization method has been followed …

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Conducted Emi Mitigation In Power Converters Using Active Emi Filters, Balaji Narayanasamy Jul 2020

Conducted Emi Mitigation In Power Converters Using Active Emi Filters, Balaji Narayanasamy

Graduate Theses and Dissertations

Wide bandgap devices enable high power density power converters. Despite the advantages of increased switching frequency, the passive components are still a major bottleneck towards enabling high power density. Among the passive components in the converter, the passive EMI filters are unavoidable to ensure compliance with conducted EMI standards. Active EMI filters help reduce the volume of the passive components and have been around for three decades now. Firstly, this work presents a summary of all the different active EMI filters based on the type of noise-sensing, noise-processing, the type of active circuits used and the type of control methods. …

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Towards High Efficiency And High Power Density Converter: System Level Design, Modulation, And Active Emi Filters, Hongwu Peng Jul 2020

Towards High Efficiency And High Power Density Converter: System Level Design, Modulation, And Active Emi Filters, Hongwu Peng

Graduate Theses and Dissertations

Power converter exposes strong challenges to its efficiency, power density and reliability. For the grid-connected inverter application, three-level (3-L) T-type neutral-point-clamped (TNPC) inverters has higher efficiency and lower total harmonic distortion (THD) compared to two-level inverter. Hybrid switch concept combines the benefit of both silicon carbide (SiC) MOSFET and Si IGBT. By applying hybrid switch structure in 3-L T-type inverter, the total power density of 3-L TNPC inverter will be higher while the cost will be lower than that of all-SiC 3-L T-type inverter. The hybrid switch based 3-L TNPC inverter also imposes challenge to its modulation and control, a …

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Investigation Of The Structural, Electronic, And Thermoelectric Properties Of Mono- Chalcogenides, Aida Sheibani Jul 2020

Investigation Of The Structural, Electronic, And Thermoelectric Properties Of Mono- Chalcogenides, Aida Sheibani

Graduate Theses and Dissertations

The structural, electronic, and thermoelectric properties of GeTe are studied using density functional theory and Boltzmann transport equations. This material has a rhombohedral crystal structure in ambient temperature with a ferroelectric behavior due to lack of inversion symmetry. This study suggests that the presence of asymmetry in GeTe can lead to an improvement in the thermoelectric properties of this material. In addition, studies on introducing Group III, IV, and V dopants to GeSe show that while these impurities can improve the power factor and decrease the lattice thermal conductivity, they cannot enhance the figure of merit.

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Nonlinear Dimensionality Reduction For The Thermodynamics Of Small Clusters Of Particles, Aditya Dendukuri Jul 2020

Nonlinear Dimensionality Reduction For The Thermodynamics Of Small Clusters Of Particles, Aditya Dendukuri

Graduate Theses and Dissertations

This work employs tools and methods from computer science to study clusters comprising a small number N of interacting particles, which are of interest in science, engineering, and nanotechnology. Specifically, the thermodynamics of such clusters is studied using techniques from spectral graph theory (SGT) and machine learning (ML). SGT is used to define the structure of the clusters and ML is used on ensembles of cluster configurations to detect state variables that can be used to model the thermodynamic properties of the system. While the most fundamental description of a cluster is in 3N dimensions, i.e., the Cartesian coordinates of …

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Development Of High-Density Propulsion System Technologies For Interplanetary Small Satellites And Cubesats, Morgan Andrew Roddy Jul 2020

Development Of High-Density Propulsion System Technologies For Interplanetary Small Satellites And Cubesats, Morgan Andrew Roddy

Graduate Theses and Dissertations

The goal of this research was to support the development of a novel propulsion system for small satellites (<180 kg) and CubeSats. This was pursued by conducting a collection of studies that were designed to provide engineering data that would be critical in designing a functional prototype. The novel propulsion system was conceived by the author to provide best-in-class performance for the small satellite and CubeSat families of spacecraft. This context presents specific design requirements that the presented technology attempts to satisfy. The most critical among these is high density; the propellant was designed to be stored with high density and the thruster was designed to be as compact as possible. The propulsion system is composed of two primary elements, a propellant generator and a thruster. The propellant generator works by sublimating a solid crystal into vapor and then using this vapor to etch a dense metal. The resulting gaseous byproducts of this reaction are the propellant. This dissertation used xenon difluoride (XeF2) vapor to etch tungsten (W) which react to form xenon gas (Xe) and tungsten hexafluoride (WF6). This approach gave a theoretical propellant storage density 5.40 g/cm3; and 5.17 g/cm3 was demonstrated. The sublimation dynamics of the XeF2 were studied as a function of surface area and temperature and it was found to be suitable for the intended application due to its high effluence rate; that is, it sublimates fast enough to be useful. The sublimation rates are on the order of 10’s of µg/s. The etch rate of XeF2 on W was also studied and found to be suitably fast to provide useful amounts of reactants for use as a propellant, again on the order of 1’s of µg/s. The thruster is an electrostatic radio frequency (RF) ion thruster design and is manufactured with Low Temperature Co-Fired Ceramic (LTCC) materials system and manufacturing technology. Manufacturing samples of the thruster were built at the University of Arkansas in July 2015 and tested at NASA’s Marshall Space Flight Center in May 2018. Testing validated the viability of the LTCC thruster and provided valuable information on how to improve the thruster’s design.

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Radiation-Balanced Fiber Lasers And Amplifiers, Esmaeil Mobini Souchelmaei Mr Jul 2020

Radiation-Balanced Fiber Lasers And Amplifiers, Esmaeil Mobini Souchelmaei Mr

Optical Science and Engineering ETDs

Over the past decades, high-power fiber lasers and amplifiers have been extensively under research to achieve higher output powers. However, temperature rise in the core of fiber lasers and amplifiers has been a big issue in power-scaling. Radiation-balancing is a viable technique introduced for effective heat mitigation in lasers and amplifiers by S. Bowman in 1995. Radiation-balancing relies on solid-state laser cooling as a self-cooling mechanism to mitigate the generated heat in lasers and amplifiers. To implement the mentioned idea in fiber lasers and amplifiers, a set of issues should be scrutinized; (i) the amenability of silica glass (as the …

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Asymptotic Analysis For Overlap In Waveform Relaxation Methods For Rc Type Circuits, Martin J. Gander, Pratik M. Kumbhar, Albert E. Ruehli Jul 2020

Asymptotic Analysis For Overlap In Waveform Relaxation Methods For Rc Type Circuits, Martin J. Gander, Pratik M. Kumbhar, Albert E. Ruehli

Electrical and Computer Engineering Faculty Research & Creative Works

Waveform relaxation (WR) methods are based on partitioning large circuits into sub-circuits which then are solved separately for multiple time steps in so called time windows, and an iteration is used to converge to the global circuit solution in each time window. Classical WR converges quite slowly, especially when long time windows are used. To overcome this issue, optimized WR (OWR) was introduced which is based on optimized transmission conditions that transfer information between the sub-circuits more efficiently than classical WR. We study here for the first time the influence of overlapping sub-circuits in both WR and OWR applied to …

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Developing A New Formula For Predicting Oil Recovery Factor In Water Flooded-Heterogeneous Reservoirs, Mohamed Khaled Aljifri Jul 2020

Developing A New Formula For Predicting Oil Recovery Factor In Water Flooded-Heterogeneous Reservoirs, Mohamed Khaled Aljifri

Theses

In this work, two sets of empirical correlations were developed for predicting the recovery factor (RF) in water-flooded layered oil reservoirs. The first set of these correlations encompasses four key parameters believed to have a significant impact on waterflooding performance, namely, reservoir heterogeneity (permeability variation coefficient), injected water viscosity, permeability anisotropy (ratio of vertical permeability to horizontal permeability), and water injection rate. This first set consists of two expanded forms, one for predicting the RF at water breakthrough time (BT) and the other for predicting the RF at the end of the project (EOP). Out of the aforementioned four key …

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Ce-Qual-W2 Hydrodynamic And Water Quality Model Of The Cedar River Municipal Watershed, Amory Spencer Cervarich Jul 2020

Ce-Qual-W2 Hydrodynamic And Water Quality Model Of The Cedar River Municipal Watershed, Amory Spencer Cervarich

Dissertations and Theses

The laterally averaged, two-dimensional model CE-QUAL-W2 was used to develop a water quality model of the Cedar River Municipal Watershed as a reservoir management and climate change scenario tool. The 90,638-acre watershed, located 56 kilometers southeast of Seattle, WA, provides drinking water to over 1.4 million people. The watershed relies on two waterbodies for storage, Chester Morse Lake and the Masonry Pool. The Masonry Dam is the main storage structure in the watershed. The Cedar River flows downstream from the Masonry Dam for 57 kilometers to Lake Washington. The reservoir model simulated Chester Morse Lake and the Masonry Pool. The …

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A Comparison Of Half And Quarter Space Penetration Into Granular Media, Ivan L. Guzman, Magued Iskander, Stephan Bless Jul 2020

A Comparison Of Half And Quarter Space Penetration Into Granular Media, Ivan L. Guzman, Magued Iskander, Stephan Bless

Publications and Research

In this study, two experimental techniques are compared for the purpose of visualizing projectile penetration at speeds ranging between 60 and 150 m/s into granular media. The two techniques are half space penetration into a transparent synthetic soil surrogate and quarter space penetration of an opaque natural sand and transparent soil surrogate against an observation window. In both techniques a pneumatic projectile accelerator was employed to launch the projectiles, and high-speed imagery was employed to visualize the penetration events unintrusively. Transparency in transparent targets was achieved by saturating angular fused quartz with a refractive index matched pore fluid made of …

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Simulation And Optimal Control Of Crude Oil Separation Process At Offshore Facilities To Improve Efficiency Of Oil And Condensate Recovery, Yee Kai Chin Jul 2020

Simulation And Optimal Control Of Crude Oil Separation Process At Offshore Facilities To Improve Efficiency Of Oil And Condensate Recovery, Yee Kai Chin

Student Works (2020-2029)

Crude oil separation process is the most crucial process in offshore production facilities in ensuring the well fluid is separated efficiently and persistently. Waxy crude or sluggish feed stream is the major disturbance that could cause operational issues and production loss due to process upset. The main objective of this research is to model offshore crude oil separation process and introduce state space control to optimize the control of total liquid and water level within the permissible range as well as to evaluate the effect of disturbances to the controls. This work presents two different modelling methods in developing three-phase …

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