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2024

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Metakaolin-Based Geopolymer Concrete; Synthesis, Development And Characterization, Heba Fouad Dec 2024

Metakaolin-Based Geopolymer Concrete; Synthesis, Development And Characterization, Heba Fouad

Theses and Dissertations

Geopolymers are rendered as an essential sustainable replacement to the widely used Ordinary Portland Cement (OPC) which causes immense carbon dioxide emissions, hence a detrimental impact on society’s health and the environment. Geopolymers are three-dimensional networks of polymerized tetrahedral silicate and aluminate in the form of Q4(4Al), Q4(3Al) and Q4(2Al) which act as the principal binding phase in concrete. Past research has reported the synthesis of geopolymers from different aluminosilicates precursors, their characterization, and their wide range properties. However, previous studies still have not properly investigated effective range of synthesis ratios for a particular source material, optimum curing regimes, short- …


Cooperative Rendezvous In Multi-Vehicle Systems, Rajeev Shobhit Voleti Dec 2024

Cooperative Rendezvous In Multi-Vehicle Systems, Rajeev Shobhit Voleti

Mechanical and Aerospace Engineering Dissertations

The field of cooperative, multi-vehicle systems has witnessed a significant expansion and evolution, yielding considerable opportunities for improved autonomy, resilience, and robustness. Despite these promising developments, complex challenges persist in ensuring secure and efficient rendezvous among cooperative peers. The term "rendezvous," within the realm of cooperative control, refers to the simultaneous convergence of multi-vehicle systems to a designated target location. In missile guidance, the problem of multiple pursuer missiles achieving rendezvous with a target is termed as a salvo attack. Current methodologies often grapple with issues related to synchronization, high latency and network security, all of which can adversely impact …


Non-Intrusive Reduced Order Model Formulation For Inverse Shape Design Including Deforming Meshes And Multiphysics Problems., Kapil Aryal Dec 2024

Non-Intrusive Reduced Order Model Formulation For Inverse Shape Design Including Deforming Meshes And Multiphysics Problems., Kapil Aryal

Mechanical and Aerospace Engineering Dissertations

Despite significant advancements in computer capabilities for numerical simulations, engineers continue to face limitations when dealing with large-scale full-order model(FOM) simulations. These simulations often necessitate repeated solves, such as those encountered in inverse design, real-time solution prediction, error quantification, and solver convergence, among others. To address these challenges, reduced order modeling (ROM) has emerged as a valuable approach. This thesis focuses on the development of an ROM framework that combines Proper Orthogonal Decomposition (POD) with machine learning techniques. This integrated approach is applied to a diverse range of heat transfer and fluid flow inverse design problems. POD constructs optimal sets …


Turbulent Shockwave/Boundary-Layer Interactions Generated By Sharp Swept Fins, Dustin Levi Otten Dec 2024

Turbulent Shockwave/Boundary-Layer Interactions Generated By Sharp Swept Fins, Dustin Levi Otten

Mechanical and Aerospace Engineering Dissertations

The shock/turbulent boundary layer interaction (STBLI) generated by a sharp fin with a 60 deg leading edge sweep mounted above a flat plate at Mach 2.5 was studied numerically. Incipient separation due to this highly swept fin was determined by varying the fin angle to the incoming freestream. The effect of a small fin/plate gap on STBLI incipient separation was established. Sweeping the fin increases the deflection required for incipient separation as the sweep reduces the interaction strength. A gap causes flow leakage under the fin, further reducing the interaction strength on the windward side. The incipient angle of attack …


Microstructural Finite Element Modeling Of High-Performance Carbon Fiber-Reinforced Composites To Characterize Microscale Material Properties And Fiber-Direction Compressive Strength, Quy Tung Ling Vu Dec 2024

Microstructural Finite Element Modeling Of High-Performance Carbon Fiber-Reinforced Composites To Characterize Microscale Material Properties And Fiber-Direction Compressive Strength, Quy Tung Ling Vu

Mechanical and Aerospace Engineering Dissertations

Carbon fiber-reinforced composites are increasingly used in aerospace application thanks to their excellent specific stiffness and strength. However, incomplete understanding of their failure behaviors leads to composite components often being designed with a high Safety Factor, limiting their advantages. Using computational methods, this project studies carbon fiber-reinforced composite microstructures for the objective of understanding and improving material performances under compression load which is one of the main considerations in primary aerospace structure design. A Finite Element (FE) model for the evaluation of composite compression behaviors was developed, allowing the identification of several key material properties affecting composite performance. The numerical …


Cooperative Manipulation And Formation Control Using Multiple Aerial Vehicles, Uluhan Cem Kaya Dec 2024

Cooperative Manipulation And Formation Control Using Multiple Aerial Vehicles, Uluhan Cem Kaya

Mechanical and Aerospace Engineering Dissertations

Recent advancements in autonomous systems have significantly impacted both academia and industry, opening new research avenues. One of them is the collaboration of multiple systems to achieve a common goal, which is known as a cooperative system. In the lack of human intelligence, decision making and perception capabilities, uncrewed autonomous systems could mutually benefit from each other’s capabilities when they are deployed and utilized together. This research tackles the collaboration of group of uncrewed aerial systems (UASs) where the constraint on individual vehicles requires a varying level of coordination and cooperation. Such cooperation can be in the form of a …


Method-Of-Characteristics Models For Flowfield Evaluation Of Hypervelocity Test Facilities, Anannthkumar Jayamani Dec 2024

Method-Of-Characteristics Models For Flowfield Evaluation Of Hypervelocity Test Facilities, Anannthkumar Jayamani

Mechanical and Aerospace Engineering Dissertations

Ground test facilities are an imperative part of the design and development of flying vehicles. In the case of high-enthalpy facilities, evaluating the gasdynamic and thermochemical state of the test gas poses challenges due to high temperature effects. This study aims to contribute to the development impulse facilities by developing reduced-order models resolving the flowfields of such facilities. Developed as a part of this study are various method-of-characteristics (MoC) algorithms which consider gases under varying levels of thermochemical complexity. The algorithms span from simple calorically perfect gases to full thermochemical nonequilibrium. The first set of algorithms was limited to unsteady …


Enhancing Concrete Sustainability With Self-Healing Technologies, Al Shimaa Abdullatif Dec 2024

Enhancing Concrete Sustainability With Self-Healing Technologies, Al Shimaa Abdullatif

Theses and Dissertations

Thanks to its strength, durability and affordability, Portland cement concrete is the most commonly used building material worldwide. However, concrete cracking is inevitable due to numerous factors including shrinkage, exposure to external chemicals, internals reactions, excessive loads, to name but a few. Self-healing is a promising technique that can enable concrete to autogenously heal cracks and alleviate much of the damage. Such healing can without a doubt extend the service life with less need for external repair works therefore it contributes to sustainability. Over the years, several means of self-healing agents have been explored including bio-based procedures and the incorporation …


Speech Coding Based On A Hybrid Approach: Dct, Huffman And Run-Length Coding, Sundos Abdulameer Alazawi, Esraa Jaffar Baker, Shahbaa Mohammed Abdulmaged Dec 2024

Speech Coding Based On A Hybrid Approach: Dct, Huffman And Run-Length Coding, Sundos Abdulameer Alazawi, Esraa Jaffar Baker, Shahbaa Mohammed Abdulmaged

Al-Esraa University College Journal for Engineering Sciences

The exponential expansion of data in the digital world necessitates the development of effective methods for data transmission and storage. Data compression (DC) strategies are suggested to reduce the quantity of data stored or conveyed due to constrained resources. As a result of DC ideas' ability to efficiently use existing storage space and transmission capacity, different methods have been developed in various areas. Speech coding is a lossy method of coding; therefore, the output signal differs slightly from the input signal. Speech coding is useful for message encryption, communication over long distances and speech quality. In the fields of digital …


The Evolution Of The University Of Al-Anbar Urban Planning Based On The Mental Picture's Diversity And The Contemporary Planning Spaces Filling, Ali Abdulsamea Hameed Dec 2024

The Evolution Of The University Of Al-Anbar Urban Planning Based On The Mental Picture's Diversity And The Contemporary Planning Spaces Filling, Ali Abdulsamea Hameed

Al-Esraa University College Journal for Engineering Sciences

This research concentrated on the role of environmental graphic design (EGD) and the place-making idea in the interior environment of Al-Anbar University. To develop an identity being visual for the University of Al-Anbar internal environment (IE) is this goal of project. The search sought to create and enhance the shape of the internal University of Al-Anbar vacuum by reviving the idea of place building. In order to build and filling the internal emptiness of the campus, the identity being visual must also be strengthened. The descriptive analytical approach was chosen since it was best suited to achieve the goal of …


Exploring The Benefits Of Feature Selection Based On Bat Algorithm And Deep Learning In Brain Cancer Diagnosis, Noor Fawzi Shafiq Dec 2024

Exploring The Benefits Of Feature Selection Based On Bat Algorithm And Deep Learning In Brain Cancer Diagnosis, Noor Fawzi Shafiq

Al-Esraa University College Journal for Engineering Sciences

Brain cancer is considered one of the most dangerous types that must be treated as soon as possible. Therefore, it is necessary to detect brain cancer in its early stages to enhance the diagnosis of the condition. This study proposes to combine the bat algorithm (BA) with deep learning methods to identify and classify brain tumors in medical images accurately.

In this paper, the bat algorithm was used to select distinctive features from the input brain images. The Bat Algorithm (BA) is a metaheuristic optimization algorithm that mimics the echolocation behavior of bats. It efficiently explores the feature space to …


An Intelligent System Using Deep Learning For Healthcare Monitoring In Light Of The Covid-19 And Future Pandemics Based On Iot, Sara Salman Qasim, Rajaa J. Khanjar, Jamal Nasir Hasoon, Baesher Abdullateff Abad, Ali Hussein Fadil, Shajan.M. Alsowaidi Dec 2024

An Intelligent System Using Deep Learning For Healthcare Monitoring In Light Of The Covid-19 And Future Pandemics Based On Iot, Sara Salman Qasim, Rajaa J. Khanjar, Jamal Nasir Hasoon, Baesher Abdullateff Abad, Ali Hussein Fadil, Shajan.M. Alsowaidi

Al-Esraa University College Journal for Engineering Sciences

Recently, the Internet of Things has become a compelling research field as a new topic of research in various disciplines, particularly in the field of healthcare, because the Internet of Things is rebuilding modern healthcare systems by integrating technology, economics, and social perspectives. The development of healthcare systems from traditional to more personalized systems in which patients can be easily diagnosed, monitored and treated and many people can be helped. People are treated and cared for remotely and this is what some people need in the crisis the world has been through like COVID-19. This epidemic is caused by the …


Capacity Of Self Compact Concrete Walls Using Attapulgite As A Partial Replacement Of Cement Under One Way And Two Way Action Restriction, Wissam Kadhim Alsaraj, Luma Abdul Ghani Zghair, Akhlas Hashem Mohammed Dec 2024

Capacity Of Self Compact Concrete Walls Using Attapulgite As A Partial Replacement Of Cement Under One Way And Two Way Action Restriction, Wissam Kadhim Alsaraj, Luma Abdul Ghani Zghair, Akhlas Hashem Mohammed

Al-Esraa University College Journal for Engineering Sciences

This investigation about the structural performance of sustainable self-compact concrete walls exposed to eccentric axial regularly dispersed loading, including the effect of aspect ratio (AR) and slenderness ratio (λ) by one-way and two-way action. The experimental program includes testing ten wall panels, the eccentricity of the loading system equivalent to one-sixth of depth. These wall panels are separated into four groups, each one consisting of three specimens. first and second groups clarify the aspect ratio (H/L) effect. The results indicated for decreasing AR from (0.75 to 0.625), (0.625 to 0.5), and (0.75 to 0.5), the increase of final load is …


A Study On Improving The Accuracy And Effectiveness Of Similarity Detection Processes In Text Files Using Nlp Techniques, Noor Abdulmuttaleb Jaafar Dec 2024

A Study On Improving The Accuracy And Effectiveness Of Similarity Detection Processes In Text Files Using Nlp Techniques, Noor Abdulmuttaleb Jaafar

Al-Esraa University College Journal for Engineering Sciences

The rapid expansion of the Internet has revolutionized access to information, especially in the area of unstructured data, most of which consists of textual content. While instant access to information brings many advantages, it has also given rise to a prevalent problem – plagiarism. Copying and reusing materials without proper permission poses a significant threat to academic integrity and integrity. Rates of plagiarism, especially in academic and scientific publications, have risen with the advent of the Internet, reaching alarming levels, such as 60% in student projects. This study examines the proposed model that includes computation of similarity using cosine coefficients, …


Unveiling The Hidden Threat: How Wireless Networks Fuel Serious Cyber Attacks, Ibtesam Jomaa Hawi Dec 2024

Unveiling The Hidden Threat: How Wireless Networks Fuel Serious Cyber Attacks, Ibtesam Jomaa Hawi

Al-Esraa University College Journal for Engineering Sciences

The spread of wireless networks has led to an increase in serious cyber attacks due to their weak architecture. This article focuses on reevaluating cybersecurity in wireless network technology by integrating statistical information detection methods and artificial intelligence (AI) algorithms. To construct a wireless networking scenario that accurately reflects real-life conditions, we created a data fabrication that included four pre-existing anomalies as well as four newly introduced anomalies. The synthetic dataset created from these generation processes contains 20 thousand distinguishable values, which are later divided into training and validation sets. Using the strategy described before, we began to analyze the …


Beyond The Surface: Understanding Temperature Polarisation In Dcmd Membranes Through Varied Operational Parameters, Hiras Ahamed Hijaz, Masoumeh Zargar, Abdellah Shafieian, Amir Razmjou, Mehdi Khiadani Dec 2024

Beyond The Surface: Understanding Temperature Polarisation In Dcmd Membranes Through Varied Operational Parameters, Hiras Ahamed Hijaz, Masoumeh Zargar, Abdellah Shafieian, Amir Razmjou, Mehdi Khiadani

Research outputs 2022 to 2026

Conventionally, a single Temperature Polarisation Coefficient (TPC) value is calculated to quantify Temperature Polarisation (TP). In this research, the extent of polarisation is investigated by capturing temperature profiles at specific points along a MD membrane using miniature thermocouples, eliminating the need for TPC calculations. The extent of polarisation at a point is affected by two contributory factors, namely the proximity of flow inlets and the difference in vapour pressure across the membrane at that point. Under this direction, this work examined the influence of permeate temperature, feed salinity, and flow direction on the development of the temperature profiles. Our analysis …


Identifying Challenges Faced By Small And Medium Enterprises (Smes) In The Middle East And North Africa (Mena) Region Through Total Quality Management, Mohamad Atef Dec 2024

Identifying Challenges Faced By Small And Medium Enterprises (Smes) In The Middle East And North Africa (Mena) Region Through Total Quality Management, Mohamad Atef

Theses and Dissertations

Recently, Small and Medium Enterprises (SMEs) have become recognized as an important driver of global economic growth and innovation. This phenomenon is particularly evident in the MENA region, where small and medium-sized enterprises (SMEs) make a significant contribution to the businesses. SMEs offer significant benefits in terms of job creation, revenue generation, and fostering economic diversity. Although SMEs have a vital contribution in the economy of the MENA region, SMEs face many challenges that hinder their development and long-term viability. Focusing on these challenges is very important for fostering a vibrant and resilient economic environment. The objective of this thesis …


Hitch Cart “Landing Gear”, Rebekah White, Jose Raygoza, Randy Hernandez, Brandon Leon Dec 2024

Hitch Cart “Landing Gear”, Rebekah White, Jose Raygoza, Randy Hernandez, Brandon Leon

Mechanical Engineering

This report aims to allow our sponsor, to review our design process of the Hitch Cart Landing Gear Prototype. In the design overview section of this report, we discuss the primary design modifications we made to the wheel mechanism of the existing hitch cart prototype, including the addition of the ACME screws and the folding brackets. This allows our sponsor to see the intended improvements made to the past prototype and understand the primary goal of our project. Then, in the implementation section, we cover the entire manufacturing process to allow our sponsor to understand what manufacturing steps must be …


Engineered Microalgae Cultivations Systems: Conversion Of Wastewater Nutrients Into Biofuels And Bioplastics, Jacob Watkins Dec 2024

Engineered Microalgae Cultivations Systems: Conversion Of Wastewater Nutrients Into Biofuels And Bioplastics, Jacob Watkins

All Graduate Theses and Dissertations, Fall 2023 to Present

Dissolved Nitrogen and Phosphorus in wastewater can contribute to harmful algae blooms if released into the environment. One technology that can be used to recover dissolved nutrients from wastewater is the Rotating Algae Biofilm Reactor (RABR), which supports microalgae growth in an easily-harvested biofilm and produces nitrogenand phosphorus-rich biomass that can be used to produce slow-release fertilizers, biofuels, and compostable bioplastics. This thesis (1) examines the effects of several environmental factors on the biomass production rate and nutrient removal efficiency of RABRs treating municipal wastewater, (2) quantifies the composition and biofuel yields of microalgae biomass cultivated using a RABR at …


Analysis Of An Outdoor Pilot-Scale Rotating Algae Biofilm Reactor For Power Optimization, Ash-Enhanced Productivity, And Nutrient Uptake, Peter F. Jeppesen Dec 2024

Analysis Of An Outdoor Pilot-Scale Rotating Algae Biofilm Reactor For Power Optimization, Ash-Enhanced Productivity, And Nutrient Uptake, Peter F. Jeppesen

All Graduate Theses and Dissertations, Fall 2023 to Present

Outdoor testing of a rotating algae biofilm reactor (RABR) was performed to see how well it could remove nutrients from water and produce algae. By adjusting the operation settings, we found the lowest power needed to remove nitrogen and phosphorus. The lowest power values needed were 1.36 kWh per kilogram of nitrogen and 20.1 kWh per kilogram of phosphorus. The algae production rate reached a maximum of 7.09 grams per square meter per day. Detailed analysis showed that the reactor worked like a continuous flow system, and the performance was influenced by factors including light and temperature. The results also …


Finite-Time Control Strategies For Rendezvous And Proximity Operations, John Tamotsu Akagi Dec 2024

Finite-Time Control Strategies For Rendezvous And Proximity Operations, John Tamotsu Akagi

All Graduate Theses and Dissertations, Fall 2023 to Present

One common metric to use when designing a controller is the time that the system will take to reach the desired state. Unfortunately, many approaches to developing controllers only guarantee that the system will approach, but not exactly reach, the desired state. This can become a limitation in time-sensitive situations where rapid and complete convergence is necessary. One group of control methods, known as finite-time control, does guarantee both faster convergence and that the desired state will be reached, but often fails to define exactly what time that will occur, how much control will be used to get there, and …


Hafnium Oxide Coating To Improve The Oxidation Behavior Of Zirconium Diboride, Jan E. Förster, William G. Fahrenholtz, Gregory E. Hilmas, Ravisankar Naraparaju Dec 2024

Hafnium Oxide Coating To Improve The Oxidation Behavior Of Zirconium Diboride, Jan E. Förster, William G. Fahrenholtz, Gregory E. Hilmas, Ravisankar Naraparaju

Materials Science and Engineering Faculty Research & Creative Works

Hafnium dioxide (HfO2) coatings were successfully deposited on zirconium diboride (ZrB2) using reactive magnetron sputtering. After the oxidation at 1500°C or 1600°C, the mutual dissolution of HfO2 and thermally grown ZrO2 was observed which has resulted in the formation of a mixed oxide zone. As the enrichment of the mixed oxide zone by ZrO2 progresses, monoclinic/tetragonal phase transition temperature of ∼1790°C for nominally pure HfO2 moves towards ∼1500 °C. Finally, the inevitable phase transition from monoclinic to tetragonal structure results in the development of cracks, pores, and gaps within the mixed oxide …


Operation Webs - Tiny Home On Wheels: Quantity Take-Off, Estimate, And Site Logistics, Brendan Moynahan Dec 2024

Operation Webs - Tiny Home On Wheels: Quantity Take-Off, Estimate, And Site Logistics, Brendan Moynahan

Construction Management

The objective of this paper is to highlight and discuss the process of performing quantity take-offs, completing an estimate, and creating a site logistics plan for the Operation WEBS (Women Empowered Build Strong) Tiny Home on Wheels project performed at the Paso Robles State Fair. This project is a part of the interdisciplinary project based senior project completed by California Polytechnic State University, San Luis Obispo, College of Architecture and Environmental Design students Brendan Moynahan and Jake Torres. Brendan Moynahan performed the deliverables covered in this paper while Jake Torres completed his own deliverables for another paper. Our individual responsibilities …


Engineering Faculty Perceptions On Student-Use Of Generative Artificial Intelligence (Gai) In Course Completion, Michaela Harper Dec 2024

Engineering Faculty Perceptions On Student-Use Of Generative Artificial Intelligence (Gai) In Course Completion, Michaela Harper

All Graduate Theses and Dissertations, Fall 2023 to Present

Computer science and engineering faculty often argue whether students should be allowed to use GAI tools, such as ChatGPT, or banned from using them for fear of decreasing learning and workforce quality. This research gathers and reports engineering and computer science faculty members’ perceptions, opinions, and recommendations for GAI use in higher education. Faculty members agree that these technologies are here to stay and must be understood to address GAI in college and university courses. However, their willingness to implement GAI into their courses varied based on prior experience in industry and with the technology itself. Those with very limited …


Performance Of Optimized Composition Of Epoxy Resin Adhesive Used In High Friction Surface Treatment, Jiapeng Li, Xiao Huan, Shubing Wang, Yanping Sheng, Dahui Xu, Zhanping You Dec 2024

Performance Of Optimized Composition Of Epoxy Resin Adhesive Used In High Friction Surface Treatment, Jiapeng Li, Xiao Huan, Shubing Wang, Yanping Sheng, Dahui Xu, Zhanping You

Michigan Tech Publications, Part 2

The High Friction Surface Treatment (HFST) paving technique is widely employed in engineering practices globally, serving to enhance the long-term anti-skid performance of pavements. However, there still exist significant gaps in research regarding the modified and optimized composition and corresponding content of the polymer binding materials used in HFST, as well as the performance of the pavements laid with modified and optimized blended aggregates during service. To address these issues, this research first modified and optimized the composition ratio of traditional epoxy resin materials. Subsequently, a toughened, high-flow epoxy bonding system suitable for the maintenance of concrete pavements was prepared. …


Using Nano-Ities For Detection Of Metal Ions In Complex Aqueous Solutions, Mohammed Muzammil Nishar Ahmed Dec 2024

Using Nano-Ities For Detection Of Metal Ions In Complex Aqueous Solutions, Mohammed Muzammil Nishar Ahmed

Theses and Dissertations

Recent urbanization has induced a rapid increase in heavy metal exposure to humans. The exploitation of heavy metals for economic gains coupled with poor and economically infeasible recycling methods have led to poor management of heavy metal wastes, which has opened up several pathways for heavy metals to enter the human body. Such heavy metals target many vital organs, but the early symptoms are common and difficult to diagnose. Severe symptoms appear in later stages and are very expensive to treat and the damage caused to the health are not typically reversable in such later stages. To counter this issue, …


Designing A Robust Lab Scale Electrocoagulation Reactor For Removal Of Micro- And Nanoplastics From Drinking Water, Emmanuel Louis Aduhene Dec 2024

Designing A Robust Lab Scale Electrocoagulation Reactor For Removal Of Micro- And Nanoplastics From Drinking Water, Emmanuel Louis Aduhene

All Graduate Reports and Creative Projects, Fall 2023 to Present

The widespread occurrence of micro and nanoplastics in drinking water sources could cause serious public health issues. These plastics particles, products of industrial operations and weathering of larger plastics, can interact with other contaminants in the environment, leading to more severe environmental pollution. Present drinking water treatment technologies were designed to remove suspended colloids. However, due to the distinct chemical and physical properties of micro and nanoplastics from conventional colloids, it is challenging for traditional chemical coagulation/flocculation/sedimentation process to achieve satisfying removal performance. This report investigates a design of a lab-scale electrocoagulation reactor for the removal of nanoplastics from drinking …


Quantitative Evaluation Of Baseflow Separation Methods Using An Integrated Hydrologic Model: A Case Study In A Snow-Dominated Watershed, Jihad Othman Dec 2024

Quantitative Evaluation Of Baseflow Separation Methods Using An Integrated Hydrologic Model: A Case Study In A Snow-Dominated Watershed, Jihad Othman

All Graduate Reports and Creative Projects, Fall 2023 to Present

Baseflow, commonly referred to as the groundwater contribution to streamflow, constitutes approximately 50% of streamflow in mountainous regions of the Western United States. Accurately quantifying the amount of baseflow is critical for water management and decision-making, as it significantly impacts stream water quality, low flow availability, and ecosystem health. Traditionally, baseflow has been estimated using conceptual and automated baseflow separation methods, which are known to be both arbitrary and ambiguous, posing a challenge to validate them. In this study, we developed an integrated hydrologic model that seamlessly integrated the exchange between surface and subsurface flows to physically quantify the baseflow …


A Secure Cross-Domain Authentication Scheme Based On Threshold Signature For Mec, Lei Chen, Chong Guo, Bei Gong, Muhammad Waqas, Lihua Deng, Haowen Qin Dec 2024

A Secure Cross-Domain Authentication Scheme Based On Threshold Signature For Mec, Lei Chen, Chong Guo, Bei Gong, Muhammad Waqas, Lihua Deng, Haowen Qin

Research outputs 2022 to 2026

The widespread adoption of fifth-generation mobile networks has spurred the rapid advancement of mobile edge computing (MEC). By decentralizing computing and storage resources to the network edge, MEC significantly enhances real-time data access services and enables efficient processing of large-scale dynamic data on resource-limited devices. However, MEC faces considerable security challenges, particularly in cross-domain service environments, where every device poses a potential security threat. To address this issue, this paper proposes a secure cross-domain authentication scheme based on a threshold signature tailored to MEC’s multi-subdomain nature. The proposed scheme employs a (t,n) threshold mechanism to bolster system resilience and security, …


Stress-Dependent Mohr–Coulomb Shear Strength Parameters For Intact Rock, Hao Li, Leo Pel, Zhenjiang You, David Smeulders Dec 2024

Stress-Dependent Mohr–Coulomb Shear Strength Parameters For Intact Rock, Hao Li, Leo Pel, Zhenjiang You, David Smeulders

Research outputs 2022 to 2026

Rock strength is imperative for the design and stability analysis of engineering structures. The Mohr–Coulomb (M-C) criterion holds significant prominence in geotechnical engineering. However, the M-C criterion fails to accurately capture the nonlinear strength response and neglects the critical state of rocks, potentially leading to inaccuracies in the design phase of deep engineering projects. This study introduces an innovative stress-dependent friction angle and cohesion (SFC) for the M-C criterion to capture the nonlinear strength responses of intact rocks, spanning from non-critical to critical states (brittle to ductile regions). A novel method for determining these stress-dependent parameters at each corresponding σ3 …