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Slope Stability Analysis Of Haditha Dam After Earthquake Using Geo-Studio Software, Mohammed K. Malik, Ibtisam R. Karim Jul 2026

Slope Stability Analysis Of Haditha Dam After Earthquake Using Geo-Studio Software, Mohammed K. Malik, Ibtisam R. Karim

Engineering and Technology Journal

The current study is designed to analyze theslope stability of Haditha damwhich is an earth-fill dam constructed on the Euphrates River in the middle-west of Iraq. Finite element modeling was used in the present study to analyze the combined seepage and post-earthquake slope stability of Haditha earth dam. The maximum water level of a steady seepage case was considered to evaluate seepage. - Three different water levels (maximum, normal, and minimum) were applied, and nine different equilibrium slope stability limits were used to analyze the upstream and downstream slopes of the dam with three horizontal maximum accelerations.The input data given …


Hybrid Pso-Rbfnn And Proposed Algorithms Of Dddwt For The Heart Disease Classification, Ansam S. Jabbar Jul 2026

Hybrid Pso-Rbfnn And Proposed Algorithms Of Dddwt For The Heart Disease Classification, Ansam S. Jabbar

Engineering and Technology Journal

This paper introduced a Particle Swarm Optimization-Radial Basis Function Neural Networks (PSO-RBFNN)-based system for heart disease detection that used the PSO algorithm to optimize RBFNN parameters. The newly developed signal digital algorithm presents the results of a new image contrast enhancement approach using Double Density Discrete Wavelet transform DDDWT for extraction of features, using adaptive DDDWT for the elimination of noise, and the use of PSO and ANN methods to classify the output from the Electrocardiogram (EGGS). It also provides identification of all techniques and MATLAB codes used to improve the processes.This approach merged the global search power of the …


Intelligent Controller Design Based On Wind-Solar System, Areeg F. Hussein, Hanan A. R. Akkar Jul 2026

Intelligent Controller Design Based On Wind-Solar System, Areeg F. Hussein, Hanan A. R. Akkar

Engineering and Technology Journal

This paper presents an Intelligent controller designed to mastery the output power flow from the Solar System, the Wind system, the sum of the two systems or from the battery system, according to the Maximum power point tracking algorithm, to ensure the continuity of the output power at fast time response. The proposed controller has been designed using MATLAB m-file and trained with the different number of hidden neurons using two different algorithms to get as fast a response time with minimum Mean Square Error (MSE) as possible which resulted in six hidden neurons using Levenberg-Marquardt training algorithms.


Pattern Recognition Of Composite Motions Based On Emg Signal Via Machine Learning, Noof T. Mahmooda, Mahmuod H. Al-Muifraje, Sameer K. Salih, Thamir R. Saeed Jul 2026

Pattern Recognition Of Composite Motions Based On Emg Signal Via Machine Learning, Noof T. Mahmooda, Mahmuod H. Al-Muifraje, Sameer K. Salih, Thamir R. Saeed

Engineering and Technology Journal

In the past few years, physical therapy plays a crucial role during rehabilitation. Numerous efforts are made to demonstrate the effectiveness of medical/ clinical and human-machine interface (HMI) applications. One of the most common control methods is using electromyography (EMG) signals generated by muscle contractions to implement the prosthetic human body parts. This paper presents an EMG signal classification system based on the EMG signal. The data is collected from biceps and triceps muscles for six different motions, i.e., bowing, clapping, handshaking, hugging, jumping, and running using a Myo armband with eight electromyography sensors. The Root Mean Square, Difference Absolute …


Smart Door For Handicapped People Via Face Recognition And Voice Command Technique, Hanaa M. Salman, Rana T. Rasheed Jul 2026

Smart Door For Handicapped People Via Face Recognition And Voice Command Technique, Hanaa M. Salman, Rana T. Rasheed

Engineering and Technology Journal

Smart home indicates an application for different technological implementations, it could indicate any system which controls the door lock and several other devices. Facial identification which is an important section to achieve surveillance and safety, especially for handicapped people, can be considered as one of the ways that deal with biometrics and performed to identify facial images via utilizing fundamental features of the face. A Raspberry Pi-based face recognition system using conventional face detection and recognition techniques is going to be supplied, so the method in which image-built biometrics uses a Raspberry Pi is described. The aim of the paper …


Data Center Enhancement By Server Resources Utilization, Haider A. Ghanem, Rana F. Ghani, Mohammed N. Fadhil Jul 2026

Data Center Enhancement By Server Resources Utilization, Haider A. Ghanem, Rana F. Ghani, Mohammed N. Fadhil

Engineering and Technology Journal

Data centers are the main nerve of the Internet because of its hosting, storage, cloud computing and other services. All these services require a lot of work and resources, such as energy and cooling. The main problem is how to improve the work of data centers through increased resource utilization by using virtual host simulations and exploiting all server resources. In this paper, we have considered memory resources, where Virtual machines were distributed to hosts after comparing the virtual machines with the host from where the memory and putting the virtual machine on the appropriate host, this will reduce the …


Survey Of Recent Video Watermarking Techniques, Taisir N. Hummadia, Nidaa F. Hassanb Jul 2026

Survey Of Recent Video Watermarking Techniques, Taisir N. Hummadia, Nidaa F. Hassanb

Engineering and Technology Journal

With the development of the Internet coupled with expanding the accessibility of multimedia, various copyright issues have resulted. Several researchers have been working on watermarks to provide the security, durability, and a perception of multimedia. This paper a review of some recent works is presented related to video watermarking techniques, this study focuses on the pros and cons of recent video watermarking, areas of application, and the different types and attacks that are standing against these watermarking techniques. The results obtained from this study showed that watermark techniques based on the transfer domain, are more popular than those of the …


Detection Face Parts In Image Using Neural Network Based On Matlab, Shahad L. Galib, Fouad S. Tahir, Asma A. Abdulrahman Jul 2026

Detection Face Parts In Image Using Neural Network Based On Matlab, Shahad L. Galib, Fouad S. Tahir, Asma A. Abdulrahman

Engineering and Technology Journal

Recently, face recognition system (FRS) is implemented in different applications including a range of vital services like airports and banking systems for security purposes. Therefore, deployed surveillance systems have been established which led to the urgent need to develop a vital face recognition system. In this work, a new algorithm was proposed for recognition of the face, personal and color images by training the convolutional neural network using the MATLAB program to build a new program for detection of the face, then building a separate program to discover the lips, nose, and eyes, New methods were explored to analyze the …


License Plate Tilt Correction: A Review, Nada N. Kamal, Enas Tariq Jul 2026

License Plate Tilt Correction: A Review, Nada N. Kamal, Enas Tariq

Engineering and Technology Journal

Tilt correction is an essential step in the license plate recognition system (LPR). The main goal of this article is to provide a review of the various methods that are presented in the literature and used to correct different types of tilt that appear in the digital image of the license plates (LP). This theoretical survey will enable the researchers to have an overview of the available implemented tilt detection and correction algorithms. That’s how this review will simplify for the researchers the choice to determine which of the available rotation correction and detection algorithms to implement while designing their …


Using Texture Feature In Fruit Classification, Mauj H. Abd Al Karim, Abdulamir A. Karim Jul 2026

Using Texture Feature In Fruit Classification, Mauj H. Abd Al Karim, Abdulamir A. Karim

Engineering and Technology Journal

Recent advances in computer vision have allowed wide-ranging applications in every area of life. One such area of application is the classification of fresh products, but the classification of fruits and vegetables has proven to be a complex problem and needs further development. In recent years, various machine learning techniques have been exploited with many methods of describing the different features of fruit and vegetable classification in many real-life applications. Classification of fruits and vegetables presents significant challenges due to similarities between layers and irregular characteristics within the class.Hence , in this work, three feature extractor/ descriptor which are local …


Determination Efficient Classification Algorithm For Credit Card Owners: Comparative Study, Raghad A. Azeez Jul 2026

Determination Efficient Classification Algorithm For Credit Card Owners: Comparative Study, Raghad A. Azeez

Engineering and Technology Journal

Today in the business world, significant loss can happen when the borrowers ignore paying their loans. Convenient credit-risk management represents a necessity for lending institutions. In most times, some persons prefer to late their monthly payments, otherwise, they may face difficulties in the loan payment process to the financial institution. Mainly, most fiscal organizations are considered managed and refined client classification systems, scanning a valid client from invalid ones. This paper produces the data mining idea, specifically the classification technique of data mining and builds a system of data mining process structure. The credit scoring problem will be applied using …


Speaker Recognition Systems In The Last Decade – A Survey, Ahmed M. Ahmed, Aliaa K. Hassan Jul 2026

Speaker Recognition Systems In The Last Decade – A Survey, Ahmed M. Ahmed, Aliaa K. Hassan

Engineering and Technology Journal

Speaker Recognition Defined by the process of recognizing a person by his\her voice through specific features that extract from his\her voice signal. An Automatic Speaker recognition (ASP) is a biometric authentication system. In the last decade, many advances in the speaker recognition field have been attained, along with many techniques in feature extraction and modeling phases. In this paper, we present an overview of the most recent works in ASP technology. The study makes an effort to discuss several modeling ASP techniques like Gaussian Mixture Model GMM, Vector Quantization (VQ), and Clustering Algorithms. Also, several feature extraction techniques like Linear …


Novel Dynamic Batch-Sensitive Adam Optimiser For Vehicular Accident Injury Severity Prediction, Daniel Asare Kyei, Alimatu Saadia-Yussiff, Maame G. Asante-Mensah, Abdul Lateef-Yussiff, Charles Roland Haruna, Derry Emmanuel Jul 2026

Novel Dynamic Batch-Sensitive Adam Optimiser For Vehicular Accident Injury Severity Prediction, Daniel Asare Kyei, Alimatu Saadia-Yussiff, Maame G. Asante-Mensah, Abdul Lateef-Yussiff, Charles Roland Haruna, Derry Emmanuel

Iraqi Journal for Computer Science and Mathematics

The choice of optimiser is important in deep learning, as it strongly influences model efficiency and speed of convergence. However, many commonly used optimisers encounter difficulties when applied to imbalanced and sequential datasets, limiting their ability to capture patterns of minority classes. In this study, we propose Dynamic Batch-Sensitive Adam (DBS-Adam), an optimiser that dynamically scales the learning rate using a batch difficulty score derived from exponential moving averages of gradient norms and batch loss. DBS-Adam improves training stability and accelerates convergence by increasing updates for difficult batches and reducing them for easier ones. We evaluate DBS-Adam by integrating it …


Genpix: A Diverse Dataset For Fake Image Detection, Guessoum Dalila, Benblidia Nadjia, Boumahdi Fatima, Remmide Mohamed Abdelkarim, Nouri Tarek-Amine, Bataouche Azeddine-Lotfi Jul 2026

Genpix: A Diverse Dataset For Fake Image Detection, Guessoum Dalila, Benblidia Nadjia, Boumahdi Fatima, Remmide Mohamed Abdelkarim, Nouri Tarek-Amine, Bataouche Azeddine-Lotfi

Iraqi Journal for Computer Science and Mathematics

The rapid advancement of sophisticated generative models has intensified the need for robust fake image detection systems. However, many existing benchmark datasets suffer from limited diversity in content types and generation techniques, constraining the generalization ability of detection models. To address these limitations, we introduce GenPix (Generalized Pixels), a comprehensive dataset encompassing over 80,000 images spanning diverse categories, including faces, objects, and scenes, generated by multiple state-of-the-art models such as Generative Adversarial Networks (GANs) and diffusion-based architectures. The dataset includes samples from different generation methods to ensure broad coverage of fake image characteristics.

GenPix provides a realistic evaluation environment that …


Eyolov8-Msaff: An Enhanced Object Detection Algorithm With Multi-Scale Attention And Feature Fusion For Small And Dense Object Detection In Uav Applications, Mohammed Hasan Mutar, Morteza Valizadeh, Alaa Hussein Abdulaal, Mehdi Chehel Amirani Jul 2026

Eyolov8-Msaff: An Enhanced Object Detection Algorithm With Multi-Scale Attention And Feature Fusion For Small And Dense Object Detection In Uav Applications, Mohammed Hasan Mutar, Morteza Valizadeh, Alaa Hussein Abdulaal, Mehdi Chehel Amirani

Iraqi Journal for Computer Science and Mathematics

The proliferation of unmanned aerial vehicles (UAVs) has necessitated the development of sophisticated object detection algorithms capable of handling the unique challenges posed by aerial imagery. Traditional detection methods often struggle with small object sizes, dense distributions, and complex backgrounds characteristic of UAV-captured scenes. This research presents EYOLOv8-MSAFF (Enhanced YOLOv8 with Multi-Scale Attention and Feature Fusion), a novel deep learning architecture specifically engineered for superior performance in UAV-based object detection tasks. The proposed methodology integrates four innovative components: a Hybrid Spatial-Channel Attention Mechanism (HSCAM) that processes attention information in parallel rather than sequentially, an Adaptive Multi-Scale Feature Fusion Module (AMSFFM) …


A Novel Hierarchical Multi-Scale Attention Mechanism For Enhanced Yolov8 Performance In Unmanned Aerial Vehicle-Based Small Object Detection, Mohammed Hasan Mutar, Morteza Valizadeh, Alaa Hussein Abdulaal, Mehdi Chehel Amirani Jul 2026

A Novel Hierarchical Multi-Scale Attention Mechanism For Enhanced Yolov8 Performance In Unmanned Aerial Vehicle-Based Small Object Detection, Mohammed Hasan Mutar, Morteza Valizadeh, Alaa Hussein Abdulaal, Mehdi Chehel Amirani

Iraqi Journal for Computer Science and Mathematics

Object detection in Unmanned Aerial Vehicle (UAV) images presents significant challenges due to the prevalence of small and densely packed objects, as well as variations in scale, orientation, and lighting conditions. This paper introduces a novel object detection algorithm, Hierarchical Multi-Scale Attention YOLO (HMSA-YOLO), which is an improved version of YOLOv8 designed to address these challenges. The proposed method incorporates a novel Hierarchical Multi-Scale Attention (HMSA) module, a Bidirectional Feature Pyramid Network (BiFPN) for enhanced feature fusion, a modified loss function, and an adaptive anchor optimization technique. The HMSA module effectively captures both channel and spatial dependencies at multiple scales, …


Comparative Performance Evaluation Of A Gpu-Accelerated Watershed Model For Flood Inundation Mapping, Maliha Ali Jul 2026

Comparative Performance Evaluation Of A Gpu-Accelerated Watershed Model For Flood Inundation Mapping, Maliha Ali

Electronic Theses and Dissertations 2020 - Present

This study evaluates PyWMP (Python-based Watershed Modeling and Planning), which is a flood modeling framework developed by the Center for Water Resiliency and Risk Reduction (CWR3) at Florida Atlantic University (FAU). The framework includes a 2D Rain-on-Mesh (ROM) solver, which is an explicit finite-volume shallow-water equation model. PyWMP is compared against HEC-RAS 2D and Flood Modeller for their rain-on-grid capabilities for watershed-scale flood inundation mapping under three design storm scenarios. The performance of PyWMP was evaluated using both quantitative and spatial metrics. Mean absolute error values showed that the average depth difference between each model is under 1 foot. Percent …


Analysis Of Flood Modeling For The Replication Of An Extreme Rainfall Event In South Florida, Lusnel Fritznel Ferdinand Jul 2026

Analysis Of Flood Modeling For The Replication Of An Extreme Rainfall Event In South Florida, Lusnel Fritznel Ferdinand

Electronic Theses and Dissertations 2020 - Present

Flooding is the most common natural disaster in the United States, and trends show an increase in flood risk for the foreseeable future. Florida averages 45 flood disasters per year, at an annual cost of $86 million. Communities in Florida are susceptible to a variety of flood-inducing sources, including tropical cyclones, extreme rainfall, and rising sea levels, which can impact the tourism industry and the economic well-being of residents. The first objective of the thesis was to use flood modeling to replicate the extreme rainfall event that caused heavy flooding in Broward County, Florida, from April 12-13, 2023. A commercial …


Improving The Fpga Radio Design Cycle: Implementing Dvb-S2 Modulation Using Verilator And Gnu Radio, Seth Pellegrino Jul 2026

Improving The Fpga Radio Design Cycle: Implementing Dvb-S2 Modulation Using Verilator And Gnu Radio, Seth Pellegrino

Dissertations and Theses

In embedded digital radio systems, a central challenge is meeting the real-time throughput required to process the samples--especially for space-bound ultra-wideband SDRs which must handle more than 100 Gbps entirely onboard. An FPGA's programmable logic offers sufficient potential, but realizing a particular radio flow is a project usually fraught with defects and long turnaround times. We simulated Verilog modules in a custom harness that adapted a Verilated model to GNU Radio, which allowed for breaking down a complicated radio flow (here, DVB-S2 modulation) into a series of well-bounded problems each with clear criteria for success. The framework, built on open …


Integrated Construction Uncertainty Quantification Framework Icuqf, Felix Delmonte Jul 2026

Integrated Construction Uncertainty Quantification Framework Icuqf, Felix Delmonte

Mechanical and Civil Engineering Faculty Publications

This study develops ICUQF, an integrated uncertainty framework for digitally instrumented construction megaprojects that unite probabilistic simulation, fuzzy reasoning, Bayesian networks, AI-driven anomaly detection, BIM-linked digital twins, and organizational learning into a single operational architecture. The framework classifies uncertainty into aleatory variability, epistemic gaps, data-centric and model-centric risks, and cognitive or cultural sources, mapping each class to computational treatments such as Monte Carlo engines for stochastic variability, fuzzy intervals and p-boxes for imprecise expert judgments, and hierarchical Bayesian models for coherent evidence aggregation and online updating. ICUQF specifies data pipelines that connect IoT sensing, edge processing, cloud storage, and Common …


Impact Of Gas Interactions With Nano Porous Geological Material In The Presence Of Water Vapor, Matthew D. Powell Jul 2026

Impact Of Gas Interactions With Nano Porous Geological Material In The Presence Of Water Vapor, Matthew D. Powell

Chemical and Biological Engineering ETDs

Predicting gas transport in nanoporous geological material requires understanding competitive adsorption and transport under humid conditions. However, most adsorption studies rely on single-component equilibrium measurements that do not capture these effects. This dissertation develops an experimental methodology to directly quantify multicomponent gas adsorption and breakthrough behavior under controlled relative humidity. The method was first applied to the Kr/Xe–N2–H2O system, where it resolved competitive adsorption behavior in humid porous media and produced a bivariate model relating noble gas adsorption to noble gas partial pressure and water saturation. The methodology was then extended to the CO2–N2 H2O system. Results showed that water …


Design And Feasibility Study Of An Air-Cooled Reactor Cavity Cooling System For Fluoride-Salt-Cooled High-Temperature Reactors, Alexandra D. Martinez Jul 2026

Design And Feasibility Study Of An Air-Cooled Reactor Cavity Cooling System For Fluoride-Salt-Cooled High-Temperature Reactors, Alexandra D. Martinez

Nuclear Engineering ETDs

Licensing efforts for Fluoride-Salt-Cooled High-Temperature Reactors (FHRs) are dependent on passive safety systems designed for decay heat removal, yet no prior study has evaluated an air-based Reactor Cavity Cooling System (RCCS) for this role. This thesis addresses that gap by determining whether an air-cooled RCCS can be designed to passively remove post-shutdown decay heat from the Mk 1 FHR. An RCCS configuration was developed and sized using a one-dimensional lumped-parameter design methodology, then evaluated through system-level thermal-hydraulic modeling in RELAP5-3D under a conservative, lower-bound post-shutdown transient. The analysis characterizes the radial heat-transfer pathways from the FHR core to the RCCS …


Development Of Dynamic Proof-Mass Configurations For Broadband Piezoelectric Energy Harvesting, Nico E. Galarza Jul 2026

Development Of Dynamic Proof-Mass Configurations For Broadband Piezoelectric Energy Harvesting, Nico E. Galarza

Electrical and Computer Engineering ETDs

The purpose of this thesis is to investigate and develop dynamic proof-mass configurations for broadband piezoelectric energy harvesting. Conventional piezoelectric energy harvesters are typically limited by narrow operating bandwidths, restricting their performance under variable-frequency excitation. This research presents the design, fabrication, and experimental evaluation of multiple proof-mass concepts intended to increase the usable frequency range of cantilever-based piezoelectric energy harvesters. Several dynamic mass configurations were developed using additive manufacturing techniques and integrated with commercially available piezoelectric cantilevers. Experimental testing was conducted under controlled vibration conditions to characterize voltage response, resonant behavior, and bandwidth performance. The results demonstrate that dynamic proof-masses …


Investigating Light-Matter Interactions In Low-Dimensional Silicon Carbide, Nishan Shrestha Jul 2026

Investigating Light-Matter Interactions In Low-Dimensional Silicon Carbide, Nishan Shrestha

Mechanical Engineering ETDs

Recent advances in materials science have transformed the study and application of low-dimensional materials, with two-dimensional (2D) systems and nanoscale structures exhibiting properties beyond their bulk counterparts. Despite significant progress in materials such as graphene and silicon, the nanoscale exploration of silicon carbide (SiC) remains relatively underdeveloped, despite its critical importance in photonics and electronics and high temperature applications. Motivated by the transformative potential of nanoscale material design and the technological importance of SiC, this dissertation investigates structure and properties of low-dimensional silicon carbide structures. It explores the synthesis and optical properties of SiC nanosheets and nanowires using a variety …


Simulations Of Atmospheric Pressure Streamer Discharges: Mechanisms Of Streamer Propagation And Related Physics, Dejan Nikic Jul 2026

Simulations Of Atmospheric Pressure Streamer Discharges: Mechanisms Of Streamer Propagation And Related Physics, Dejan Nikic

Electrical and Computer Engineering ETDs

Gas discharge simulations are performed with particular focus on photoionization process in a positive streamer discharge. The effects of this process are investigated by isolating the change in photoionization mean free path (MFP) and keeping the additional processes constant. Furthermore, comparison are made between various effects of simulation parameters, such as initial conditions, geometry extent, simula- tion particle count etc. All of these simulations are performed using a modern Direct Simulation Monte Carlo Particle-in-Cell (DSMC-PIC) code developed by Sandia Na- tional Laboratories. Large scale simulations including 1 cm and 5 cm electrode gaps are performed under standard atmospheric condition air. …


Rthermal: Gate Level Power And Thermal Simulation For 3d-Stacked Chips, Peter Xiong Jul 2026

Rthermal: Gate Level Power And Thermal Simulation For 3d-Stacked Chips, Peter Xiong

Master's Theses

As the number of transistors in modern processors increases, heat dissipation has become a major bottleneck to scalability. The use of 3D stacking further intensifies this problem, as heat from multiple layers can accumulate vertically. These challenges create a growing need for tools that can accurately and efficiently simulate the thermal behavior of 3D chips during design and validation. Several existing tools model thermal behavior for 3D-stacked chips and can simulate average heat over large spatial regions or long time intervals. However, when heat is concentrated in a small area or over a short time window, such models can miss …


Preparation And Performance Study Of In-Situ Self-Assembled Biphasic Smmn2O5-Nimn2O4 Composite Cathode, Neng-Chu Xia, Yu Zhou, Qin Wang, Jia-You Zhang, Chun Yu, Yang Zhang, Wan-Bing Guan, Jian-Xin Wang Jul 2026

Preparation And Performance Study Of In-Situ Self-Assembled Biphasic Smmn2O5-Nimn2O4 Composite Cathode, Neng-Chu Xia, Yu Zhou, Qin Wang, Jia-You Zhang, Chun Yu, Yang Zhang, Wan-Bing Guan, Jian-Xin Wang

Journal of Electrochemistry

Mullite-structured oxides exhibit excellent oxygen reduction reaction activity, possess a low thermal expansion coefficient due to their unique crystal structure, and can eliminate the need for a barrier layer and simplify the preparation process as they contain no alkaline earth elements. Thus, they hold great promise as novel cathode materials for solid oxide fuel cells. In this work, a mullite-spinel-structured SmMn2O5-NiMn2O4 (SMO-NMO) composite cathode was one-step synthesized via a solid-liquid composite route, and its in-situ self-assembly enabled good compatibility with the electrolyte without any barrier layer. Characterization results showed that the SMO:NMO = …


In-Situ Stm Visualization Of Molecular Structural Evolution During Electrochemical Oxidation Coupling Of Para-Aminothiophenol On Au(111), Zi-Wei Ma, Tai-Rui Wu, An-Ni Zheng, Lai-Ke Chen, Yuan-Hui Xiao, Zhao-Bin Chen, Qing-Na Zheng, Jian-Zhang Zhou, Jia-Wei Yan, De-Yin Wu Jul 2026

In-Situ Stm Visualization Of Molecular Structural Evolution During Electrochemical Oxidation Coupling Of Para-Aminothiophenol On Au(111), Zi-Wei Ma, Tai-Rui Wu, An-Ni Zheng, Lai-Ke Chen, Yuan-Hui Xiao, Zhao-Bin Chen, Qing-Na Zheng, Jian-Zhang Zhou, Jia-Wei Yan, De-Yin Wu

Journal of Electrochemistry

Para-aminothiophenol (PATP) is not only a widely-used probe molecule in the field of surface-enhanced Raman spectroscopy (SERS), but also an important model molecule for interfacial reactions, exhibiting distinct photo- and electro-oxidation pathways, so that PATP is selectively activated under different external fields. The evolution of products and intermediates during electrochemical oxidative coupling remains unknown. In this study, we have investigated the dynamic electrochemical oxidation process of PATP on the Au(111) surface using cyclic voltammetry, electrochemical (EC)-SERS, and in situ electrochemical scanning tunneling microscopy (EC-STM). The results showed that PATP forms an unsaturated adsorption coverage on Au(111) in an acidic solution. …


Wildfire Impacts On Fluvial Hydrology From Watershed To National Scales, Paige G. Tunby Jul 2026

Wildfire Impacts On Fluvial Hydrology From Watershed To National Scales, Paige G. Tunby

Civil Engineering ETDs

Wildfires alter the water quantity and quality in downstream river networks. Fires promote biodiversity, maintain habitat, and provide many ecosystem services in a fire-adapted landscape. However, changes in the natural fire regimes can alter ecosystem function and threaten the water security of impacted downstream communities. The magnitude, timing, and persistence of these impacts are difficult to predict due to the lack of high-resolution datasets with adequate coverage to evaluate spatiotemporal trends after a fire. This dissertation moves us beyond the status quo to evaluate post-fire fluvial responses across scales, from the event-scale impacts after the Hermit’s Peak-Calf Canyon wildfire in …


Effect Of Geothermal Conditions On Silica Flour Modified Wellbore Cement, Travis Benjamin Broadhurst Jul 2026

Effect Of Geothermal Conditions On Silica Flour Modified Wellbore Cement, Travis Benjamin Broadhurst

Civil Engineering ETDs

Considerable work has been conducted on modified wellbore cements, but a knowledge gap exists in the effects of downhole conditions on cement, especially tensile strength. In this study, a pressure vessel simulates representative downhole conditions (2000C, 1.5 MPa) with a reference solution for geothermal brine and naturally occurring geothermal gases. Samples are removed after 28-days for unconfined compressive strength testing, Brazilian tensile strength testing, elastic moduli measurement, and chemical analyses by X-ray diffraction and electron microprobe. Aqueous chemical analysis suggests multiple active reactions between the geothermal fluid and cement that are exacerbated by higher temperatures, but do not …