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Articles 8251 - 8280 of 198101

Full-Text Articles in Engineering

Determination Of Excess Pore Pressure In Under Consolidating Soil By Using Cptu, Karolina Villa Delfia Ihut, Martin Wijaya, Aswin Lim, Alfrendo Satyanaga, Grisella Aglia, Sharfina Faradiba Syifanaya, Andy Sugianto Aug 2025

Determination Of Excess Pore Pressure In Under Consolidating Soil By Using Cptu, Karolina Villa Delfia Ihut, Martin Wijaya, Aswin Lim, Alfrendo Satyanaga, Grisella Aglia, Sharfina Faradiba Syifanaya, Andy Sugianto

Makara Journal of Technology

North Jakarta is predominantly composed of soft soil that is still undergoing consolidation. According to research by Raharjo et al. (2022), excess pore pressure is still present in the soils of Jakarta. The degree of consolidation and excess pore pressure values indicate that consolidation is not yet complete (Raharjo et al., 2022). In this study, the researchers developed two methods to determine excess pore pressure using field testing. The Stress History and Normalized Soil Engineering Properties (SHANSEP) model equation from Ladd and Foot (1974), as well as Finite Element Method (FEM) modeling using the PLAXIS program, were utilized …


A Green Concrete Mixture Using Rice Husk As Partially Cement Replacement, Khloud Khalid Eldamshiry, Zeina Salama, Amany Micheal, Rania Rushdy Moussa, Ayatallah Raafat Aug 2025

A Green Concrete Mixture Using Rice Husk As Partially Cement Replacement, Khloud Khalid Eldamshiry, Zeina Salama, Amany Micheal, Rania Rushdy Moussa, Ayatallah Raafat

Architectural Engineering

Egypt's agricultural waste production has increased significantly in recent decades, leading to improper disposal methods and environmental pollution. Rice husks are the most common agricultural solid waste in Egypt, contributing to "black clouds" and causing health issues. On the other hand, Cement, a crucial component of construction materials, generates unsound residues and greenhouse gas emissions. Green concrete with rice husks could be a profitable solution for environmentally sound construction, reducing cement consumption and increasing the durability and integrity of new materials. This study investigates the use untreated rice husk fibres with a concrete mixture, avoiding burning and contributing to environmental …


Effect Of Contact Time And Concentration On Adsorption Of Pb2+Metal Ion Utilizing Crab Shell Chitosan And Activated Bentonite Clay Composite, Nia Sasria, Adi Wisaka, Ade Wahyu Yusariarta Putra Parmita, Gusti Umindya Nur Tajalla Aug 2025

Effect Of Contact Time And Concentration On Adsorption Of Pb2+Metal Ion Utilizing Crab Shell Chitosan And Activated Bentonite Clay Composite, Nia Sasria, Adi Wisaka, Ade Wahyu Yusariarta Putra Parmita, Gusti Umindya Nur Tajalla

Makara Journal of Technology

Indonesia produced 1,508 tons of nonliving crabs in the January–March 2020 period. The number of shells generated can account for 40%–60% of the overall weight. Therefore, using crab shells made into chitosan is expected to increase the economic value and reduce waste from crab shells. Chitosan can be modified with clay previously activated with an acid solution to form a chitosan–clay composite to improve the adsorption capacity. This study aims to analyze the differences in characteristics between chitosan and clay before and after the immobilization process. A comparison of chitosan and clay (1:2) is conducted on the basis of variations …


The Utilisation Of The Fourth Industrial Revolution (4ir) Technologies In E-Government Service Delivery: A Systematic Literature Review, Arnet Zitha, Noluntu Mpekoa, Sheethal Tom Aug 2025

The Utilisation Of The Fourth Industrial Revolution (4ir) Technologies In E-Government Service Delivery: A Systematic Literature Review, Arnet Zitha, Noluntu Mpekoa, Sheethal Tom

African Conference on Information Systems and Technology

The integration of Fourth Industrial Revolution (4IR) technologies is transforming e-Government by boosting citizen engagement and enhancing service efficiency. However, gaps still exist in understanding the various applications, impacts, and barriers to adoption. This systematic review synthesises literature from 16 studies published between 2017 and 2025, illustrating how technologies like blockchain, artificial intelligence, big data, Internet of Things, and machine learning are employed and their effects on e-Government service delivery. The review reveals that 4IR technologies continue to play a vital role in e-Government services by addressing security threats, simplifying verification and authentication, building trust, and improving the quality and …


Human-Machine Communication: Complete Volume. Volume 10 Aug 2025

Human-Machine Communication: Complete Volume. Volume 10

Human-Machine Communication

This is the complete volume of HMC Volume 10.


The Emergence Of Ai Chatbots In Education, Trek Martin Aug 2025

The Emergence Of Ai Chatbots In Education, Trek Martin

Journal of Graduate Education Research

The recent advent of popular AI applications in educational contexts has sparked renewed interest in the question of AI and guided learning platforms as teaching tools. What are the possibilities for learning? In the attempt to answer that question, limitations of the field must be brought to full attention, as well an understanding of whether or not those limitations will continue into the immediate future; this research examines the technical evolution of artificial intelligence in education, from early symbolic reasoning systems to modern machine-learning-based chatbots. It then examines that evolution in terms of the key challenges it faced throughout, and …


Piezoelectric Dc Generator Through Sequential In-Phase Polarization Variation, Hyun Soo Kim, Sunghoon Hur, In Woo Oh, Chulwan Lim, Huimin Qiao, Hyung Jin Choi, Min Seok Kim, Dae Sol Kong, Jong Hoon Jung, Joonchul Shin, Seung Hyub Baek, Jun Chen, Chong Yun Kang, Jeong Min Baik, Yu U. Wang, Shashank Priya, Seong H. Kim, Yunseok Kim, Hyung Suk Oh, Kyung Hoon Cho, Jungho Ryu, Hyun Cheol Song Aug 2025

Piezoelectric Dc Generator Through Sequential In-Phase Polarization Variation, Hyun Soo Kim, Sunghoon Hur, In Woo Oh, Chulwan Lim, Huimin Qiao, Hyung Jin Choi, Min Seok Kim, Dae Sol Kong, Jong Hoon Jung, Joonchul Shin, Seung Hyub Baek, Jun Chen, Chong Yun Kang, Jeong Min Baik, Yu U. Wang, Shashank Priya, Seong H. Kim, Yunseok Kim, Hyung Suk Oh, Kyung Hoon Cho, Jungho Ryu, Hyun Cheol Song

Michigan Tech Publications

Energy harvesting has drawn growing interest as a reliable power source for IoT applications, with piezoelectric materials notable for their high sensitivity and straightforward integration. Their robust mechanical-electrical coupling also makes them ideal for harnessing environmental vibrations or mechanical motions. Still, standard piezoelectric harvesters inherently produce alternating current (AC), necessitating complex rectification steps and leading to substantial energy loss. This work introduces a direct current (DC) harvesting method that employs a novel in-phase polarization strategy, enabling a stable, continuous DC output. This approach surpasses prior attempts that offered only low or pulsed DC signals, achieving an open-circuit voltage of 33.44 …


An Audio Data-Driven Roadway Digital Twin And Its Underlying Framework For A Digitized Transportation Construction Environment, Anisha Deria, Pedro J. Chacon Dominguez, Yong-Cheol Lee, Jin W. Choi Aug 2025

An Audio Data-Driven Roadway Digital Twin And Its Underlying Framework For A Digitized Transportation Construction Environment, Anisha Deria, Pedro J. Chacon Dominguez, Yong-Cheol Lee, Jin W. Choi

Michigan Tech Publications

The increasing need to build and maintain transportation systems has led project managers to manage multiple projects simultaneously. Roadway projects often entail several miles of job site, making it difficult to keep track of progress and maintenance activities. To improve the situation, this study proposes an audio data-driven roadway digital twin framework for real-time and remote monitoring of construction projects. The latent characteristics of a digital twin required for establishing a digitized work environment were investigated. As a primary method of seamlessly linking virtual and physical environments, audio data classified and analyzed by deep neural network (DNN) has been employed …


Deep Learning And Machine Learning Based Prediction Of Significant Wave Height Along The Grand Coast Of Dakar, Senegal, Dialo Diop, Xu Dongsheng, Sanjay Kumar Shukla Aug 2025

Deep Learning And Machine Learning Based Prediction Of Significant Wave Height Along The Grand Coast Of Dakar, Senegal, Dialo Diop, Xu Dongsheng, Sanjay Kumar Shukla

Research outputs 2022 to 2026

Recently, deep learning (DL) has become an essential tool for processing large datasets and is playing a crucial role in scientific research. It significantly contributes to protecting the marine environment and forecasting oceanic phenomena. This study applies an autoregressive integrated moving average model (ARIMA) time series model to forecast significant wave heights (SWHs) at two beaches in Dakar, Senegal: Malika and Yoff. Additionally, the long short-term memory network (LSTM) is used for comparative analysis. Both models estimate SWH for future predictions ranging from 12 hours to 60 days. The study utilized ERA5 reanalysis data, comprising 52584 elements of SWH and …


Smart Mobility Technologies In Urban Areas Of Emerging Economies: A Bibliometric Analysis, Peter Mugisha, Rose Luke, Joash Mageto, Hossana Twinomurinzi Aug 2025

Smart Mobility Technologies In Urban Areas Of Emerging Economies: A Bibliometric Analysis, Peter Mugisha, Rose Luke, Joash Mageto, Hossana Twinomurinzi

African Conference on Information Systems and Technology

Despite the adoption of smart mobility solutions in emerging economies, challenges such as traffic congestion, pollution and inadequate infrastructure still persist. This study analyses 540 scholarly articles published between 2003 and 2024 to evaluate how smart mobility technologies – such as Intelligent Transportation Systems (ITS), Internet of Things (IoT) and Artificial Intelligence (AI) – have been implemented in these regions. Data was retrieved from Scopus and Web of Science and analysed using Biblioshiny for bibliometric mapping and Atlas.ti for thematic analysis. The review identifies research trends and gaps, showing how ITS has improved transport management in cities like Nairobi, and …


Modeling, Control, And Learning For Whole-Body Manipulation With Large-Scale Soft Robots, Curtis C. Johnson Aug 2025

Modeling, Control, And Learning For Whole-Body Manipulation With Large-Scale Soft Robots, Curtis C. Johnson

Theses and Dissertations

This dissertation addresses the challenge of enabling soft robots to perform contact-rich manipulation tasks by overcoming limitations in hardware, modeling, control, and learning. First, we present hardware advancements with PneuDrive, a pneumatic control system for actuating soft robots. We also introduce Baloo, a hybrid soft-rigid robotic torso which achieves a single-arm payload capacity of 19.3 kg and robust whole-body grasping capabilities. We also develop a full-body tactile sensing system enabling piezoresistive sensor arrays to cover large areas (1 square meter) with over 8000 distributed sensing points. Second, we focus on developing tractable dynamic models based on the Recursive Newton-Euler algorithm …


Effect Of Saccharin On Crystallization Behavior Of Electroless Cobalt Plating, Yu-Xin Luo, Jing-Jing Wang, Lu Wang, Zi-Yi Yan, Yi Ma, Xin Bo, Jing-Shuang Dang, Zeng-Lin Wang Aug 2025

Effect Of Saccharin On Crystallization Behavior Of Electroless Cobalt Plating, Yu-Xin Luo, Jing-Jing Wang, Lu Wang, Zi-Yi Yan, Yi Ma, Xin Bo, Jing-Shuang Dang, Zeng-Lin Wang

Journal of Electrochemistry

In the process of electroless cobalt plating, the saccharin additive can significantly change the surface morphology, texture orientation, and conductivity of the cobalt coating layer. When the amount of saccharin was 3 mg·L–1, the cobalt coating transformed from disordered large grains to a honeycomb structure, with a preferred orientation of (002) facet on hexagonal close-packed (HCP) cobalt crystals. The resistivity of the cobalt film decreased to 14.4 μΩ·cm, and further decreased to 10.7 μΩ·cm after the annealing treatment. When the concentration of saccharin was increased, the grain size was gradually refined and a “stone forest” structure was observed, …


Predicting The Response Of Tendon-Driven Prosthetic Finger With Hyperelastic Joints, Lucas Gallup, Mohamed Trabia, Brendan O'Toole Aug 2025

Predicting The Response Of Tendon-Driven Prosthetic Finger With Hyperelastic Joints, Lucas Gallup, Mohamed Trabia, Brendan O'Toole

Mechanical Engineering Faculty Research

Properly designed prosthetics hands can enhance the quality of life for those suffering from limb loss. Recently, 3D-printed prosthetic hands are becoming common. In these prostheses, fingers flex through the tendons that are activated by motion of the wrist. To provide spring action, thermoplastic polyurethane (TPU) hyperelastic joints are used to connect digits to each other as well as to the wrist. While these designs are common, no model for the relationship between tendon tension and joint flexion is available. This work has developed a quasi-static virtual work-based model to predict the relationship between tendon forces and the flexion of …


Superhydrophilic Porous Coooh Nano-Architecture With Abundant Oxygen Vacancies For Enhanced Urea Electrooxidation At Ampere-Level Current Densities, Wen-Jing Lv, Xiao-Man Tang, Xue-Tong Wang, Wen-Cai Liu, Jian-Wen Zhu, Guo-Jing Wang, Yuan-Zhi Zhu Aug 2025

Superhydrophilic Porous Coooh Nano-Architecture With Abundant Oxygen Vacancies For Enhanced Urea Electrooxidation At Ampere-Level Current Densities, Wen-Jing Lv, Xiao-Man Tang, Xue-Tong Wang, Wen-Cai Liu, Jian-Wen Zhu, Guo-Jing Wang, Yuan-Zhi Zhu

Journal of Electrochemistry

The conversion of urea-containing wastewater into clean hydrogen energy has gained increasing attention. However, challenges remain, particularly with sluggish catalytic kinetics and limited long-term stability of urea oxidation reaction (UOR). Herein, we report the loosely porous CoOOH nano-architecture (CoOOH LPNAs) with hydrophilic surface and abundant oxygen vacancies (Ov) on carbon fiber paper (CFP) by electrochemical reconstruction of the CoP nanoneedles precursor. The resulting three-dimensional electrode exhibited an impressively low potential of 1.38 V at 1000 mA·cm−2 and excellent durability for UOR. Furthermore, when tested in an anion exchange membrane (AEM) electrolyzer, it required only 1.53 V at …


Low Head Dam Fatalities Data 1900 To August 2025, Rollin H. Hotchkiss, Edward William Kern, John Guymon, Paige A. Gordichuk Aug 2025

Low Head Dam Fatalities Data 1900 To August 2025, Rollin H. Hotchkiss, Edward William Kern, John Guymon, Paige A. Gordichuk

ScholarsArchive Data

This dataset documents fatalities at low head dams in the United States between 1900 and August 2025. The records were compiled between 2012 and 2025 by research assistants at Brigham Young University under the direction of Dr. Rollin Hotchkiss. Data were incorporated into the database from Dr. Bruce Tschantz, Charlie Walbridge of the American Whitewater Association, public submissions through a “Report an Incident” form, and publicly available sources, including newspaper archives and public records. Originally stored in a MySQL database and later transferred to Google Sheets, the August 2025 version was exported to Excel. The purpose of the dataset is …


Structure Regulation Engineering For Biomass-Derived Carbon Anodes Enabling High-Rate Dual-Ion Batteries, Rui Zhou, Rui Liu, Yun-Nuo Li, Si-Jie Jiang, Tian-Tian Jing, Yan-Song Xu, Fei-Fei Cao Aug 2025

Structure Regulation Engineering For Biomass-Derived Carbon Anodes Enabling High-Rate Dual-Ion Batteries, Rui Zhou, Rui Liu, Yun-Nuo Li, Si-Jie Jiang, Tian-Tian Jing, Yan-Song Xu, Fei-Fei Cao

Journal of Electrochemistry

Dual-ion batteries (DIBs) usually use carbon-based materials as electrodes, showing advantages in high operating voltage, potential low cost, and environmental friendliness. Different from conventional “rocking chair” type secondary batteries, DIBs perform a unique working mechanism, which employ both cation and anion taking part in capacity contribution at an anode and a cathode, respectively, during electrochemical reactions. Graphite has been identified as a suitable cathode material for anion intercalation at high voltages (> 4.8 V) with fast reaction kinetics. However, the development of DIBs is being hindered by dynamic mismatch between a cathode and an anode due to sluggish Li+ …


First Principles Materials Discovery And Design For Photovoltaic And Solar Thermal Alloys Using High Throughput Methods, Andrew Pike Aug 2025

First Principles Materials Discovery And Design For Photovoltaic And Solar Thermal Alloys Using High Throughput Methods, Andrew Pike

Dartmouth College Ph.D Dissertations

Materials selection has been a challenge since the dawn of time. With the advent of computational methods and high throughput databases, materials can be discovered and assessed before they are even synthesized. In this thesis I will discuss my work towards designing new materials for clean energy uses, especially alloys which have been underexplored from computational methods. To begin, I present a case study explaining the synthesis of the Yb14ZnSb11 thermoelectric material. Next, I explore the class of AM2Pn2 Zintl materials. From the previously identified BaCd2P2, it is suspected that …


Design And Optimization Of Anode Catalysts For Direct Ethanol Fuel Cells: Advances And Challenges In C-C Bond Activation And Selective Modulation Of The C1 Pathway, Kai-Chi Qin, Meng-Tian Huo, Yu Liang, Si-Yuan Zhu, Zi-Hao Xing, Jin-Fa Chang Aug 2025

Design And Optimization Of Anode Catalysts For Direct Ethanol Fuel Cells: Advances And Challenges In C-C Bond Activation And Selective Modulation Of The C1 Pathway, Kai-Chi Qin, Meng-Tian Huo, Yu Liang, Si-Yuan Zhu, Zi-Hao Xing, Jin-Fa Chang

Journal of Electrochemistry

Direct ethanol fuel cells (DEFCs) are a promising alternative to conventional energy sources, offering high energy density, environmental sustainability, and operational safety. Compared to methanol fuel cells, DEFCs exhibit lower toxicity and a more mature preparation process. Unlike hydrogen fuel cells, DEFCs provide superior storage and transport feasibility, as well as cost-effectiveness, significantly enhancing their commercial viability. However, the stable C–C bond in ethanol creates a high activation energy barrier, often resulting in incomplete electrooxidation. Current commercial platinum (Pt)- and palladium (Pd)-based catalysts demonstrate low C–C bond cleavage efficiency (


Methane Partial Oxidation With Ni-Mg-Al Hydrotalcites: Impact Of Magnesium On Catalyst Performance, Dalia A. Ali Dr. Aug 2025

Methane Partial Oxidation With Ni-Mg-Al Hydrotalcites: Impact Of Magnesium On Catalyst Performance, Dalia A. Ali Dr.

Chemical Engineering

The partial oxidation of methane (POM) is a promising route for hydrogen-rich syngas production with lower energy requirements compared to steam reforming. Herein, Ni-incorporated Mg-Al hydrotalcite- derived mixed oxide catalysts (5Ni-HT-x, x = 60, 65, 70, 75 wt.% Mg) were synthesized via co-precipitation and evaluated for CH₄ conversion and H₂ yield. Characterization techniques, including X-ray Diffraction (XRD), X-ray Photoelectron Spectroscopy (XPS), BET, H₂-TPR, TEM, FTIR, TGA, and Raman spectroscopy, were employed to investigate catalyst structure, active site stability, and carbon deposition. As a constituent of hydrotalcite-derived mixed oxides (HT), Ni2+ is strongly bound within the hydrotalcite- derived mixed oxides structure, …


Pressure And Force Dynamics In Artificial Muscle Actuators: A State-Space And Optimization-Based Approach, Mohammad Elzein Aug 2025

Pressure And Force Dynamics In Artificial Muscle Actuators: A State-Space And Optimization-Based Approach, Mohammad Elzein

Dissertations and Theses

This two-part investigation explores the dynamic behavior of braided pneumatic actuators (BPAs) under bio-inspired pulse modulation, with the aim of improving their biomimetic force output and control. The first study examines the effect of pulse length and inter-pulse timing on BPA performance, revealing that force output is highly sensitive to the temporal structure of input pulses mirroring biological muscle behavior. Using dual-pulse actuation schemes, the results demonstrate that force responses exceed the additive contributions of individual pulses, with peak amplification occurring consistently at a 27 ms inter-pulse gap. Shorter pulse lengths (10–20 ms) yielded the highest normalized force increases, up …


Hydrosocial Ocean Commons: Offshore Wind Energy In Oregon, Bryce Ashlyn Sprauer Aug 2025

Hydrosocial Ocean Commons: Offshore Wind Energy In Oregon, Bryce Ashlyn Sprauer

Dissertations and Theses

The ocean has been culturally and legally conceptualized as a commons, a space of subsistence inherited by all. Enclosure or privatization creates overlapping jurisdictions of ocean space. The ocean is also the world's most significant carbon capture, absorbing billions of tons of anthropogenic carbon dioxide since the Industrial Revolution. Now, the ocean offers an additional opportunity to decarbonize energy production and reduce greenhouse gas emissions through 'new frontiers' of offshore wind technology; however, this potential is entangled within neoliberalism. Offshore wind is entering a fragmented legal landscape where the social-legal process of ocean jurisdiction remains contested. As the "new frontier" …


Upcycling Waste To Wealth: Cuo-Sio₂/Reduced Graphene Nanocomposite From Pomegranate Peels For One-Pot Low-Temperature Conversion Of Waste Oils Into Valuable Fatty Acid Monomers, Attia Attia, Shahenda Mahran Dr., Maria Centeno Prof., Basudeb Saha Aug 2025

Upcycling Waste To Wealth: Cuo-Sio₂/Reduced Graphene Nanocomposite From Pomegranate Peels For One-Pot Low-Temperature Conversion Of Waste Oils Into Valuable Fatty Acid Monomers, Attia Attia, Shahenda Mahran Dr., Maria Centeno Prof., Basudeb Saha

Petroleum Engineering and Gas

and hence reduce the price of the fatty acid monomers. This study reports for the first time a novel, environmentally benign, highly active copper oxide-silica oxide/reduced graphene oxide (CuO-SiO2/RGO), heterogeneous nano-catalyst derived from waste pomegranate peels, for the one-pot, low-temperature synthesis of fatty acid monomers from high-acid-value waste vegetable oil (WVO). The synthesised nano-catalyst was extensively characterised using XRD, FT-IR, TEM, SEM, EDX and TGA-DTA. Further, it was utilised to synthesise fatty acidrich oleic phenoxypropyl acrylate (OPA) monomer from high acid value WVO via a single-step reaction.


Assessing Solar Radiation Patterns In Sarawak Using Measured Data And The Hargreaves-Samani Model For Photovoltaic Systems Application, Chun Yong Soo, Xian Hwa Chan, Wan Mohamad Husni Wan Mokhtar, Ahmad Rujhan Mohd Rais Aug 2025

Assessing Solar Radiation Patterns In Sarawak Using Measured Data And The Hargreaves-Samani Model For Photovoltaic Systems Application, Chun Yong Soo, Xian Hwa Chan, Wan Mohamad Husni Wan Mokhtar, Ahmad Rujhan Mohd Rais

Makara Journal of Technology

This study evaluates the Hargreaves-Samani model for estimating solar radiation in five locations in Sarawak: Bintulu, Kapit, Sri Aman, Kuching, and Miri (Subis), using minimum and maximum temperatures as key inputs. Analysis reveals stable minimum temperatures (19.7 °C to 28.8 °C), supporting consistent solar radiation patterns favorable for Photovoltaic (PV) performance. Miri (Subis) recorded the highest daily maximum temperature of 44.8 °C, while Kuching had the lowest at 24.7 °C, highlighting significant regional climatic variability. Analysis also indicates strong solar potential in Bintulu, Kapit, Sri Aman, Kuching, and Miri, with radiation peaking at 7.5 kWh/m², though seasonal variations impact PV …


Direct Control Strategy Using Polynomial Fuzzy-Based Adaptive Fractional Order Pid Controller, Ali Rospawan, Clara Lavita Angelina, Faisal Samsuri, Muhammad Yeza Baihaqi, Edmun Halawa, Muhammad Munajat, Vincent Vincent, Surawan Setiyadi, Irwan Purnama, Joni Welman Simatupang Aug 2025

Direct Control Strategy Using Polynomial Fuzzy-Based Adaptive Fractional Order Pid Controller, Ali Rospawan, Clara Lavita Angelina, Faisal Samsuri, Muhammad Yeza Baihaqi, Edmun Halawa, Muhammad Munajat, Vincent Vincent, Surawan Setiyadi, Irwan Purnama, Joni Welman Simatupang

Makara Journal of Technology

This paper presents a novel direct control strategy using a polynomial fuzzy neural network-based adaptive fractional order proportional integral derivative (PFNN-AFOPID) controller for nonlinear and time-varying systems. The proposed approach integrates the enhanced flexibility of fractional order calculus PID with the superior nonlinear approximation capabilities of polynomial fuzzy models, enabling dynamic adjustment of all control parameters without requiring precise mathematical modeling of system dynamics. By extending traditional PID control with fractional-order operations, the controller achieves improved frequency response and robustness against disturbances. Experimental validation on a DC motor position control system demonstrates significant performance improvements. Compared to traditional PID, the …


Explaining Time Series Classifiers Through Post-Hoc Xai Methods Capturing Temporal Dependencies, Ephrem Tibebe Mekonnen Aug 2025

Explaining Time Series Classifiers Through Post-Hoc Xai Methods Capturing Temporal Dependencies, Ephrem Tibebe Mekonnen

Conference papers

Time series classification is essential in domains such as healthcare and finance, where accurate predictions can have significant real-world consequences. However, in many high-stakes applications, understanding why a model makes a certain decision is just as important as the prediction itself. While deep learning models excel at capturing complex temporal patterns, their black-box nature limits transparency, making it difficult to trust and interpret their decisions. Although eXplainable AI (XAI) methods have advanced considerably for image and tabular data, applying them to time series remains challenging due to the intricate temporal dependencies and high dimensionality of the data. Post-hoc model-agnostic XAI …


Computational Fluid Dynamics (Cfd) Modeling For Bio-Inspired Aerodynamic Optimization In Autonomous Drones, Hyginus C.O. Unegbu, Danjuma Saleh Yawas Aug 2025

Computational Fluid Dynamics (Cfd) Modeling For Bio-Inspired Aerodynamic Optimization In Autonomous Drones, Hyginus C.O. Unegbu, Danjuma Saleh Yawas

Makara Journal of Technology

This study explores the aerodynamic benefits of bio-inspired design modifications for autonomous drones using advanced Computational Fluid Dynamics (CFD) simulations. Four bio-inspired configurations—leading-edge serrations, winglets, riblet surfaces, and curved wings—were assessed and compared against a baseline drone model to evaluate their impact on aerodynamic performance. The results indicated that all bio-inspired designs significantly enhanced lift, reduced drag, and improved overall aerodynamic efficiency. The leading-edge serration configuration achieved the highest performance gains, with a 33.6% increase in maximum lift coefficient (CL) and a 29.5% improvement in lift-to-drag ratio (CL/CD), primarily due to delayed flow separation and reduced turbulence. Winglets minimized wingtip …


Free-Running Ring Oscillators For Crystal-Free Communication Systems: Design, Simulation Challenges, And Frequency Stability Improvements, Haziq Rohail Aug 2025

Free-Running Ring Oscillators For Crystal-Free Communication Systems: Design, Simulation Challenges, And Frequency Stability Improvements, Haziq Rohail

Dissertations and Theses

This thesis presents techniques for enhancing the frequency stability of ring oscillators (ROs) for crystal-free wireless communication systems. The first major contribution is a tutorial-style study of frequency stability metrics, providing clear definitions, conversions methods, and comparative analysis of commonly used figures of merit such as phase noise, Allan deviation, and jitter. The second contribution addresses the challenges of simulating phase noise in free-running ROs. Key techniques including Periodic Steady-State Noise (PNoise), Harmonic Balance Noise (HBNoise), and transient noise analysis are evaluated in terms of accuracy, convergence behavior, and simulation runtime. Based on these results, practical guidelines are offered for …


Impact Of Fault Resistance On The Performance Of Ann-Based Faults Classification In The Farm Of Pv Systems, Anwer Mahmood Fadhil, Omar Sharaf Al-Deen Al-Yozbaky Aug 2025

Impact Of Fault Resistance On The Performance Of Ann-Based Faults Classification In The Farm Of Pv Systems, Anwer Mahmood Fadhil, Omar Sharaf Al-Deen Al-Yozbaky

AUIQ Technical Engineering Science

This research provides an analytical study of the effect of fault resistance on the accuracy of fault classification in solar farms, with the aim of evaluating the performance of classification algorithms in realistic environments where the characteristics of electrical signals resulting from faults change. A model of a 290kW photovoltaic farm, consisting of 100 strings each containing 7 solar panels, was adopted, and the simulation was carried out using MATLAB/Simulink software. The study included different scenarios for electrical faults, such as line-to-ground (LG) and line-to-line (LL) failures, with the failure impedance changing from 0 to 500 ohms by a step …


Assessment Of The Thermal Performance Of Cables At Zummar Station, Considering The Impact Of Harmonics, Riyad Zaki Sabri Younis, Khaled Mohammed Othman Aug 2025

Assessment Of The Thermal Performance Of Cables At Zummar Station, Considering The Impact Of Harmonics, Riyad Zaki Sabri Younis, Khaled Mohammed Othman

AUIQ Technical Engineering Science

This study evaluates the thermal impact of harmonic distortion on underground power cables through a real-life case study conducted at the Zummar 33/11 kV substation. Field measurements indicated that the cable most exposed to thermal stress was the one supplying an industrial area, where a Total Harmonic Distortion (THD) level of 23.8% was recorded due to nonlinear loads. Numerical simulations were carried out using the Finite Element Method (FEM) to analyze the thermal performance of the cable system under different seasonal loading conditions. The results showed that harmonics not only increased the temperature of the affected cable but also indirectly …


Hourly Simulated Power Production Data With Snow Loss Model At Existing Utility-Scale Pv Sites (>5 Mw) In The U.S. Eastern Interconnection In 2018, Shelbie Wickett, Ana Dyreson Aug 2025

Hourly Simulated Power Production Data With Snow Loss Model At Existing Utility-Scale Pv Sites (>5 Mw) In The U.S. Eastern Interconnection In 2018, Shelbie Wickett, Ana Dyreson

Simulated Solar Capacity Including Snow Cover in the Eastern U.S.

Project Summary: We ran PySAM power production simulations for utility-scale (>5 MW) PV sites located in the U.S. Eastern Interconnection in the year 2018. Site panel mounts (fixed-tilt or single-axis tracking), capacities, and locations (latitudes and longitudes) were extracted from Lawrence Berkeley National Laboratory's Utility-Scale Solar 2024 Edition dataset. See 2018_PV_existing_site_metadata.csv file for individual site metadata.