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Full-Text Articles in Engineering

Comparison Of [18f]Fdg With 18f-Labeled Amino Acids For Pet Imaging Of Breast Cancer, Ugur Akca Jan 2022

Comparison Of [18f]Fdg With 18f-Labeled Amino Acids For Pet Imaging Of Breast Cancer, Ugur Akca

All ETDs from UAB

Triple-negative breast cancer (TNBC) are identified by their lack of estrogen re-ceptor, progesterone receptor, and overexpression of human epidermal growth factor re-ceptor 2-gene. The glucose analog, 2-deoxy-2-[18F]-fluoro-D-glucose (FDG) is the most often utilized PET tracer for imaging TNBC. The use of FDG for imaging primary and metastatic brain tumors is limited by high FDG uptake in normal brain tissue and some forms of inflammation. Also, MRI brain imaging methods have limitation in determining the differentiation between recurrent malignant and treatment effect. Radiolabeled amino acids (AAs), which have a lower uptake in normal brain and inflammation compared to FDG, can be …


A Framework For Enterprise Systems Based On Process Improvement, Abdulrahman Alharthi Jan 2022

A Framework For Enterprise Systems Based On Process Improvement, Abdulrahman Alharthi

All ETDs from UAB

We introduce a framework for enterprise systems based on process-centered analysis. Because technology has drastically altered many aspects of our lives, such as work, leisure, travel, government, and company interactions worldwide, companies must strategically consider the Internet of Things in order to thrive in the new economy. Tanik and Jololian offered early work in this area, and included an analysis of the T-Strategy introduced by R.T. Yeh et al. in their book “Zero-time.” Our approach builds on this decade-old work, and involves the introduction of information flow analysis to process improvement [1]. We have identified two key points: centralization and …


A Framework For Designing Blockchain Systems In A Smart City Setting, Mohammad Alhefdi Jan 2022

A Framework For Designing Blockchain Systems In A Smart City Setting, Mohammad Alhefdi

All ETDs from UAB

As main characteristics of successful smart cities, the high demand for increased data security and accessibility and citizen engagement mean the role of blockchain technology has begun to increase. Nonetheless, blockchain technology also faces several challenges, which have slowed its adoption. In response, this dissertation introduces a framework for designing blockchain systems in a smart city setting and considers the smart city and blockchain challenges. Researchers have proposed several smart city models that study and analyze the complexity of smart cities to improve city security, functionality, services, and smartness. The proposed information-theoretical modeling approach to generate an innovated blockchain model …


Improving Continuity And Quality Assurance In Internet Of Things Infrastructure Using Blockchain, Hussain A. Alshehri Jan 2022

Improving Continuity And Quality Assurance In Internet Of Things Infrastructure Using Blockchain, Hussain A. Alshehri

All ETDs from UAB

In this research I present a rigorous study on the service continuity and quality assurance using the Internet of Things (IoT). The research aims at identifying risks and improving the risk mitigation tools that are currently in use for improving the IoT performance, and for pushing forward the implementation of IoT in mission critical applications. This objective can be accomplished by identifying the impact of the strategic planning, quality assurance, performance assurance, and risk management on the IoT used in businesses. While the focus is mainly on the business continuity domain, the technical aspects of IoT solutions are also covered. …


Modeling Local Heat-Exposure Vulnerability And Canopy-Level Thermal Comfort In Different Urban-Vegetation Morphology, Samain Sabrin Jan 2022

Modeling Local Heat-Exposure Vulnerability And Canopy-Level Thermal Comfort In Different Urban-Vegetation Morphology, Samain Sabrin

All ETDs from UAB

Globally, most cities experience Urban Heat Islands (UHIs) phenomena which increase the heat accumulation rate within city areas compared to the suburban and rural areas. In addition, poor air quality results in a higher prevalence of heat-related mortalities-morbidities and acute respiratory diseases. Vulnerability to UHIs impacts and air pollution varying in neighborhood scale is a function of factors including temperature pattern, the concentration of major air pollutants, land surface characteristics, socioeconomic factors, vulnerable age groups, and people's susceptibility to heat and pollution. Therefore, identifying vulnerability becomes crucial to adapt to changing climate and plan for mitigation strategies. Chapter one proposes …


Electromechanical Mechanisms Of Electromigration - Novel Approaches, Raghavendra Rao Morusupalli Jan 2022

Electromechanical Mechanisms Of Electromigration - Novel Approaches, Raghavendra Rao Morusupalli

All ETDs from UAB

Reliability of today’s interconnect lines in microelectronic devices is critical to product lifetime. The metal interconnects are carriers of large current densities and mechanical stresses, which can cause void formation or metal extrusion into the passivation leading to failure. The modeling and simulation of stress evolution caused by electromigration in interconnect lines and vias can provide a means for predicting the time to failure of the device. Reliability and performance are equally important in the microelectronics industry of today. Product lifetimes are expected to be as high as 10 to 15 years of service. A typical microprocessor has millions of …


Modeling Probabilistic Combinational Optimization Problems On Graphs Using Communication Channel, William Ngambou Djakam Jan 2022

Modeling Probabilistic Combinational Optimization Problems On Graphs Using Communication Channel, William Ngambou Djakam

All ETDs from UAB

This thesis studies Combinatorial Optimization Problems (COPs) on graphs that integrate uncertainty in the problem definition. We focus on Probabilistic Combinatorial Optimization Problems (PCOPs), where uncertainty is associated with the presence or absence of subsets of vertices that describe the problem. In general, combinatorial optimization problems are formulated as a Mixed Integer Linear Programming (MILP) model. This process aims to convert elements of decision-making into variables considering related constraints and choosing an objective function. In such cases, it is recommended to define an objective function that is a linear function with linear constraints. Also, when practical problems are formulated as …


How Does Loss Of Pulsatility Lead To Non-Surgical Bleeding In Continuous Flow Ventricular Assist Device Patterns, Khahn Tu Nguyen Jan 2022

How Does Loss Of Pulsatility Lead To Non-Surgical Bleeding In Continuous Flow Ventricular Assist Device Patterns, Khahn Tu Nguyen

All ETDs from UAB

The primary goal of this study is to evaluate the effect of diminished pulsatility associat-ed with Continuous Flow Ventricular Assist Devices (CF-VADs) on endothelial respons-es of pro-angiogenic/proinflammatory soluble factors and von Willebrand Factor (vWF). Non-surgical bleeding is one of the most common adverse events after CF-VAD implan-tation and is a major cause of morbidity in patients supported by CF-VAD therapy. Alt-hough the exact mechanisms remain unclear, development of arteriovenous malfor-mations (AVMs) and acquired von Willebrand factor syndrome (AVWS) are widely be-lieved to be major risk factors. Another challenge with the study of pulsatility is that pre-clinical studies to understand how …


Tissue Engineered Cardiac Muscle Patches With Human Pluripotent Stem Cells Enhance The Repairing Efficacy Of Infarcted Cardiac Muscle In Mouse Model, Xi Lou Jan 2022

Tissue Engineered Cardiac Muscle Patches With Human Pluripotent Stem Cells Enhance The Repairing Efficacy Of Infarcted Cardiac Muscle In Mouse Model, Xi Lou

All ETDs from UAB

Myocardial infarction (MI) remains one of the major contributors to heart failure, which can lead to death, and there has been a lack of effective treatments so far. Human pluripotent stem cells (hPSCs) have been found to be an encouraging candidate for MI treatment. But it is facing challenge of low engraftment, limited integration of transplanted cells with host myocardium. To enhance the therapeutic efficacy of stem cell therapy of MI treatment, two approaches have been explored: 1)The first approach was to overexpress N-cadherin (CDH2), a cell-cell adhesion molecule, in human induced pluripotent stem cell-derived cardiomyocytes (CDH2-hiPSC-CMs), and examine its …


Investigation Of Zinc Aluminate As A Refractory Material, Somnath Mandal Jan 2022

Investigation Of Zinc Aluminate As A Refractory Material, Somnath Mandal

All ETDs from UAB

As used chrome-based refractories may contain toxic Cr6+, the chrome-free phas-es qandilite (Mg2TiO4) and zinc aluminate (ZnAl2O4, gahnite) are being considered which are known to enhance thermomechanical properties and slag corrosion resistance. The pore generation and deleterious expansion during in situ Mg2TiO4 and ZnAl2O4 for-mation can limit their amount in a refractory composition. Hence, preformed, dense ag-gregates are desirable. Dilatometric studies revealed that when dead burned magnesia (DBM) is combined with industrial anatase instead of rutile, it expanded less (1% versus 7.2%) and the reaction occurred earlier (965℃ compared to 1120℃). The anatase-based qandilite aggregate had 0% porosity and a …


Role Of Electrophysiological Markers In Cognition In Parkinson's Disease, Adeel A. Memon Jan 2022

Role Of Electrophysiological Markers In Cognition In Parkinson's Disease, Adeel A. Memon

All ETDs from UAB

Parkinson's disease (PD) is more than a movement disorder, and non-motor symptoms, including cognitive deficits and sleep disorders, present early and adversely affect the quality of life of a person with Parkinson's disease (PwP). Unfortunately, no pharmacological therapies slow or halt the progression of cognitive decline in PD. A substantial obstacle to developing effective cognitive therapies is the heterogeneous cognitive profile in PD, as well as a lack of a reliable biomarker of cognitive impairment. Moreover, the ideal biomarker would be generalizable, widely accessible, easily measured, non-invasive, and, ideally, modifiable. Unfortunately, thus far, proposed markers of cognitive deficits often include …


A Value-Based Framework For Process Alignment In Complex Provisioning Systems, Michael Lipscomb Jan 2022

A Value-Based Framework For Process Alignment In Complex Provisioning Systems, Michael Lipscomb

All ETDs from UAB

Provisioning systems are human-built, process-based systems whose activities are directed toward providing something of value to another entity. The things provided are not limited to any one type but may include, for example, objects, services, and information. Systems under consideration herein are limited to those that are human based, decentralized, and complex. “Human based” means that many of the agents and all the customers of the system are human. “Decentralized” means that agents act beyond central control. Such a system presents different challenges from one in which tasks are delegated from a central authority. In a decentralized system, agents are …


Biomanufacturing Of Micro-Myocardial Tissue Through Suspension Differentiation With Improved Yields, Purity, And Quality, Asher M. Kahn-Krell Jan 2022

Biomanufacturing Of Micro-Myocardial Tissue Through Suspension Differentiation With Improved Yields, Purity, And Quality, Asher M. Kahn-Krell

All ETDs from UAB

Despite major advances in revascularization and drug therapy for post-myocardial infarction (MI) heart failure (HF), heart transplantation remains the only curative therapy to prevent progressive and debilitating disease. Researchers have long sought a replenishable and expandable source of cardiomyocytes (CMs), the primary functional cell in the heart muscle, for a broad array of applications related to the treatment of HF ranging from direct implantation to high throughput drug testing. The lack of cell cycle activity and cell division in adult CMs prevented the development of an expandable primary cell line. However, with the discovery of high efficiency stem cell differentiation …


Mechanotransduction Signaling On Ovarian Cancer Results In Increased Proliferation, Migration, And Chemoresistance In 2d And 3d In Vitro And In Vivo Models, Molly Buckley Jan 2022

Mechanotransduction Signaling On Ovarian Cancer Results In Increased Proliferation, Migration, And Chemoresistance In 2d And 3d In Vitro And In Vivo Models, Molly Buckley

All ETDs from UAB

Mechanical forces imparted on an ovarian tumor have recently been shown to have a grave impact on cancer development, progression, metastasis, and chemoresistance. The forces present include compression throughout the tumor, intrinsic and extrinsic shear stresses from ascitic fluid present in the peritoneal cavity as well as blood flow through the tumor via leaky and disorganized vessels created through tumor angiogenesis, and tension at the tumor periphery because of the constantly growing mass. Studies of the signaling pathways impacted by these mechanical forces could give great insight into new therapeu-tic targets for ovarian cancer, however, these studies have been severely …


Engineering Studies Towards Simultaneous Imaging Of Membrane Potential And Calcium Transients In Beating Hearts, Garrett Wood Jan 2022

Engineering Studies Towards Simultaneous Imaging Of Membrane Potential And Calcium Transients In Beating Hearts, Garrett Wood

All ETDs from UAB

Optical mapping uses fluorescent reporters to image propagation of signals like transmembrane potential (Vm) and/or calcium transients (CaT) in the heart with high spatiotemporal resolution. Simultaneous optical mapping of transmembrane potential and intracellular free calcium has been described in motionless ex vivo heart preparations, but simultaneous optical mapping of voltage and calcium in beating hearts is complicated by motion artifact and has yet to be reported. Studying these two parameters in beating hearts could produce invaluable information about the interactions between them under normal and pathophysiologic conditions. This thesis presents hardware development and design studies to demonstrate the feasibility of …


Developing Criteria For The Provision Of Alabama Service Assistance Program (Asap) Service, Charles Nwachukwu Agusiobo Jan 2022

Developing Criteria For The Provision Of Alabama Service Assistance Program (Asap) Service, Charles Nwachukwu Agusiobo

All ETDs from UAB

The Alabama Department of Transportation’s (ALDOTs) Alabama Service Assistance Program (ASAP) helps facilitate the safe and efficient movement of people and goods by providing Safety Service Patrols (SSP) along major interstates in Alabama and utilizing effective incident management strategies to minimize the impacts of freeway incidents. Efficient operation of ASAP improves timely emergency response, increases operational efficiency of the transportation facilities, improves user satisfaction, and results in safety benefits including prevention of secondary crashes. This study focused on developing a new methodology that can determine with greater efficiency when and where ASAP services are needed. The proposed methodology can replace …


Klf2 Regulation Of Glycocalyx Expression, Barrier Function, And Thromboinflammation In Human Lung Microvascular Endothelial Cells, Cambria O'Grady Jan 2022

Klf2 Regulation Of Glycocalyx Expression, Barrier Function, And Thromboinflammation In Human Lung Microvascular Endothelial Cells, Cambria O'Grady

All ETDs from UAB

KLF2 is an important transcription factor for maintaining vascular homeostasis. Its expression in endothelial cells is triggered by shear stress. The endothelial glycocalyx also plays a role in regulating vascular function, and prior work has shown that glycocalyx expression is affected by shear stress as well. However, the direct link between KLF2 and mechanisms that regulate glycocalyx synthesis has not been established. In the present study, we used human lung microvascular endothelial cells (HLMVECs) to observe changes in glycocalyx expression, barrier function, and thromboinflammation caused by KLF2 overexpression. Lentiviral transduction was the method used for KLF2 overexpression, resulting in a …


Spectrum-Efficient High-Density Data Communication For Wireless Sensor Networks, Md. Kamal Hossain Jan 2022

Spectrum-Efficient High-Density Data Communication For Wireless Sensor Networks, Md. Kamal Hossain

All ETDs from UAB

Spectrum-efficient data telemetry is critically important in high-density wireless sensor networks. The rapid expansion of the sensor network has generated a large volume of data on the limited bandwidth and brought new challenges, including transmission bottlenecks, latency, and congestion. The existing wireless technologies cannot support the proliferation of sensor devices for the limitations of spectrum and resources, including computational power, memory, and feature size that hinder the deployment of sophisticated signal processing. To overcome these limitations, orthogonal pulse-based telemetry provides an excellent alternative with reduced complexity, data compression, and efficient transmission. However, the number of data channels also limits the …


Validation Of The Ambassador Questionnaire For Undergraduate Students Conducting Engineering Outreach, Melissa G. Kuhn, Shanan Chappell Moots, Joanna K. Garner Jan 2022

Validation Of The Ambassador Questionnaire For Undergraduate Students Conducting Engineering Outreach, Melissa G. Kuhn, Shanan Chappell Moots, Joanna K. Garner

Center for Educational Partnerships Publications

Although K-12 engineering outreach commonly involves college students, the young professionals who act as ambassadors for their field are less likely to be studied than the students they serve. Yet, outreach activities may offer opportunities for undergraduate students to develop aspects of their professional selves. As there is currently no comprehensive measure that allows researchers, program evaluators, and outreach advisors to examine ambassadors' professional development and growth, this study sought to develop and validate an Ambassador Questionnaire (AQ). The multi-step process included the selection and adaptation of items from extant measures of engineering students' motivation, beliefs, professional skills, and perceptions …


A Physics-Based Model For Frost Buildup Under Turbulent Flow Using Direct Numerical Simulations, ‪Nadim Zgheib, N. Farzaneh, S. Balachandar, S. A. Sherif Jan 2022

A Physics-Based Model For Frost Buildup Under Turbulent Flow Using Direct Numerical Simulations, ‪Nadim Zgheib, N. Farzaneh, S. Balachandar, S. A. Sherif

Mechanical Engineering Faculty Publications

We present a new model for frost buildup under turbulent (and laminar) flow using direct numerical simulations. The physical model consists of two layers, the air and the frost. The air layer is fully resolved and consists of solving for the velocity, temperature, and vapor mass fraction fields. The frost layer thickness is resolved using conservation of mass and energy. Both phases are dynamically coupled using the immersed boundary method. Three-dimensional simulations are conducted in an open-channel configuration. A number of challenges need to be overcome to make these simulations feasible. First, to enforce far-field conditions of zero …


Efficient Near Infrared To Visible Light Upconversion From Er/Yb Codoped Pvdf Fibrous Mats Synthesized Using A Direct Polymer Doping Technique, Saptasree Bose, Jack Ryan Summers, Bhupendra B. Srivastava, Victoria Padilla-Gainza, Manuel Peredo, Carlos Trevino De Leon, Bryan Hoke, Santosh K. Gupta, Karen Lozano Jan 2022

Efficient Near Infrared To Visible Light Upconversion From Er/Yb Codoped Pvdf Fibrous Mats Synthesized Using A Direct Polymer Doping Technique, Saptasree Bose, Jack Ryan Summers, Bhupendra B. Srivastava, Victoria Padilla-Gainza, Manuel Peredo, Carlos Trevino De Leon, Bryan Hoke, Santosh K. Gupta, Karen Lozano

Mechanical Engineering Faculty Publications

Highlights

  • Direct Rare Earth doping in PVDF Polymer to overcome powder limitation.

  • PVDF Fiber with smooth and defect free texture designed by Forcespinning.

  • Doping Enhances Beta fraction of PVDF without affecting thermal Stability.

  • Efficient upconversion of NIR into visible light in PVDF:Yb3+,Er3+ fibrous mats.

  • Two-Photon absorption for both green and red upconversions.

Abstract

Upconverting-materials are capable of converting near infra-red (NIR) excitation into lower wavelengths. These materials could have a myriad of promising potential applications. However, in some areas, its use has been hindered by its low upconversion luminescence (UCL) efficiency and processing/handling disadvantages from luminescent materials in powder form. …


A Graph-Based Approach To Boundary Estimation With Mobile Sensors, Sean Onufer Stalley, Dingyu Wang, Gautam Dasarathy, John Lipor Jan 2022

A Graph-Based Approach To Boundary Estimation With Mobile Sensors, Sean Onufer Stalley, Dingyu Wang, Gautam Dasarathy, John Lipor

Electrical and Computer Engineering Faculty Publications and Presentations

We consider the problem of adaptive sampling for boundary estimation, where the goal is to identify the two dimensional spatial extent of a phenomenon of interest. Motivated by applications in estimating the spread of wildfires with a mobile sensor, we present a novel graph-based algorithm that is efficient in both the number of samples taken and the distance traveled. The key idea behind our approach is that by sampling locations close to known cut edges (edges whose vertices lie on opposite sides of the boundary), we can reliably find additional cut edges. Our approach repeats this process of using the …


Incentivizing Distributed Energy Resource Participation In Grid Services, Tylor Slay, John M. Acken, Robert B. Bass Jan 2022

Incentivizing Distributed Energy Resource Participation In Grid Services, Tylor Slay, John M. Acken, Robert B. Bass

Electrical and Computer Engineering Faculty Publications and Presentations

The bulk power system is experiencing a dramatic shift as renewable generation growth continues to accelerate. Large-scale renewables adoption will help societies transition to a low-carbon, low-cost, and environmental-friendly electrical power system. However, the transition from a paradigm of generation following load to one where load follows generation will require large-scale interconnection and coordinated operation of Distributed Energy Resources (DERs), supported by open communication protocols. In this future grid scenario, DER aggregations will provide critical grid services that enable high penetration levels of renewable generation. This position paper presents an Energy Service Interface (ESI) that defines scope for ensuring secure, …


A Field Test Of Direct Load Control Of Water Heaters And Its Implications For Consumers, Midrar Adham, Manasseh Obi, Robert B. Bass Jan 2022

A Field Test Of Direct Load Control Of Water Heaters And Its Implications For Consumers, Midrar Adham, Manasseh Obi, Robert B. Bass

Electrical and Computer Engineering Faculty Publications and Presentations

Utilities and customers are now operating more closely than ever. The prevailing numbers of grid-interactive Distributed Energy Resources are being integrated to provide grid reliability and stability. Different methods of control have been implemented to utilize these Distributed Energy Resources, such as Service-Oriented Load Control and Direct Load Control. This paper investigates the issues associated with the latter. A Direct Load Control method is applied to two Distributed Energy Resources, Electric Water Heater and Heat Pump Water Heater. A load shifting scenario is created where each water heater turns off during water draw events that coincide with peak demand periods. …


A Means For Tuning Primary Frequency Event Detection Algorithms, Sean Keene, Landon Hanks, Robert B. Bass Jan 2022

A Means For Tuning Primary Frequency Event Detection Algorithms, Sean Keene, Landon Hanks, Robert B. Bass

Electrical and Computer Engineering Faculty Publications and Presentations

Power system balancing authorities are routinely affected by sudden frequency fluctuations. These frequency events can precipitate cascading outages and cause damage to both customer-owned and utility equipment. In this document, we describe an Algorithm Evaluation Environment that uses a suite of metrics to evaluate an algorithm and quantify its efficacy. Using the Algorithm Evaluation Environment, a detection algorithm can be tuned to best match the definition of a frequency event as defined by experts within the context of their own balancing area. We demonstrate the utility of the Algorithm Evaluation Environment using a regression-based frequency event detection algorithm. This algorithm …


Engineering Countermeasures For Left Turns At Signalized Intersections: A Review, Siby Samuel, Amandeep Singh, Yusuke Yamani Jan 2022

Engineering Countermeasures For Left Turns At Signalized Intersections: A Review, Siby Samuel, Amandeep Singh, Yusuke Yamani

Psychology Faculty Publications

Left turn crashes can impact the safety of the drivers due to the speed and angle at which they occur. Left turns are specifically reported to affect older drivers more than the other types of crashes. This paper provides a review of the existing engineering countermeasures that have been evaluated to improve driver safety at left turns. Twenty- eight studies on left turn signal displays (protected left turns, flashing yellow arrow, and digital countdown timers), intersection geometry (offset left turn lanes, diverging diamond interchange, roundabouts, exit lanes for left turn, left turn bay extension, and contraflow left turn lanes), and …


Part I - Ai And Data As Medical Devices, W. Nicholson Price Ii Jan 2022

Part I - Ai And Data As Medical Devices, W. Nicholson Price Ii

Other Publications

It may seem counterintuitive to open a book on medical devices with chapters on software and data, but these are the frontiers of new medical device regulation and law. Physical devices are still crucial to medicine, but they – and medical practice as a whole – are embedded in and permeated by networks of software and caches of data. Those software systems are often mindbogglingly complex and largely inscrutable, involving artificial intelligence and machine learning. Ensuring that such software works effectively and safely remains a substantial challenge for regulators and policymakers. Each of the three chapters in this part examines …


An Intelligent Approach For Predicting The Strength Of Geosynthetic-Reinforced Subgrade Soil, Muhammad Nouman Amjad Raja, Sanjay K. Shukla, Muhammad Umer Arif Khan Jan 2022

An Intelligent Approach For Predicting The Strength Of Geosynthetic-Reinforced Subgrade Soil, Muhammad Nouman Amjad Raja, Sanjay K. Shukla, Muhammad Umer Arif Khan

Research outputs 2014 to 2021

In the recent times, the use of geosynthetic-reinforced soil (GRS) technology has become popular for constructing safe and sustainable pavement structures. The strength of the subgrade soil is routinely assessed in terms of its California bearing ratio (CBR). However, in the past, no effort was made to develop a method for evaluating the CBR of the reinforced subgrade soil. The main aim of this paper is to explore and appraise the competency of the several intelligent models such as artificial neural network (ANN), least median of squares regression, Gaussian processes regression, elastic net regularisation regression, lazy K-star, M-5 model …


Influence Of Mineralogy And Surfactant Concentration On Zeta Potential In Intact Sandstone At High Pressure, Faisal Ur Rahman Awan, Ahmed Al-Yaseri, Hamed Akhondzadeh, Sefan Iglauer, Alireza Keshavarz Jan 2022

Influence Of Mineralogy And Surfactant Concentration On Zeta Potential In Intact Sandstone At High Pressure, Faisal Ur Rahman Awan, Ahmed Al-Yaseri, Hamed Akhondzadeh, Sefan Iglauer, Alireza Keshavarz

Research outputs 2014 to 2021

Hypothesis:

Zeta-potential in the presence of brine has been studied for its application within hydrocarbon reservoirs. These studies have shown that sandstone’s zeta-potential remains negatively charged, non-zero, and levels-off at salinities > 0.4 mol.dm−3, thus becoming independent of salinity when ionic strength is increased further. However, research conducted to date has not yet considered clay-rich (i.e. clay ≥ 5 wt%) sandstones.

Experiments:

Firstly, streaming potential measurements were conducted on Bandera Gray sandstones (clay-rich and clay-poor) with 0.6 and 2 mol.dm−3 NaCl brine-saturated in pressurised environments (6.895 MPa overburden and 3.447 MPa back-pressure). Secondly, the streaming potential was determined …


Thermoeconomic Analysis And Multi-Objective Optimization Of A Novel Trigeneration System Consisting Of Kalina And Humidificationdehumidification Desalination Cycles, Pooria Behnam, Meysam Faegh, Iman Fakhari, Pouria Ahmadi, Ehsan Faegh, Marc A. Rosen Jan 2022

Thermoeconomic Analysis And Multi-Objective Optimization Of A Novel Trigeneration System Consisting Of Kalina And Humidificationdehumidification Desalination Cycles, Pooria Behnam, Meysam Faegh, Iman Fakhari, Pouria Ahmadi, Ehsan Faegh, Marc A. Rosen

Research outputs 2022 to 2026

Low-temperature geothermal heat sources have the highest share of geothermal energy in the world. Utilization of these heat sources for energy and freshwater generation can play an important role in meeting energy and freshwater demands. To do so, this study aims to propose a novel trigeneration cycle powered by low-temperature geothermal sources. The proposed system, which is an integration of Kalina and humidification-dehumidification (HDH) cycles, is used for the generation of electricity, heating, and freshwater. For the Kalina cycle, an evaporative condenser is used. It also acts as a humidifier and heater of the humidification-dehumidification desalination cycle, resulting in a …