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Articles 1 - 30 of 10269
Full-Text Articles in Engineering
Hardware Acceleration Of Numerical Methods For Solving Ordinary Differential Equations, Soham Bhattacharya
Hardware Acceleration Of Numerical Methods For Solving Ordinary Differential Equations, Soham Bhattacharya
Theses and Dissertations
Along with the advancement in technology, the role of hardware accelerators is increasing consistently, delivering advancements in scientific simulations and data analysis in scientific computing, signal processing tasks in communication systems, matrix operations, and neural network computations in artificial intelligence and machine learning models. On the other hand, several high-speed computer applications in this era of high-performance computing often depend on ordinary differential equations (ODEs); however, their nonlinear nature can present a challenge to obtaining analytic solutions. Consequently, numerical approaches prove effective in delivering only approximate solutions to these equations. This research discusses the implementation of a customized hardware accelerator …
Shape Memory Alloy Capsule Micropump For Drug Delivery Applications, Youssef Mohamed Kotb
Shape Memory Alloy Capsule Micropump For Drug Delivery Applications, Youssef Mohamed Kotb
Theses and Dissertations
Implantable drug delivery devices have many benefits over traditional drug administration techniques and have attracted a lot of attention in recent years. By delivering the medication directly to the tissue, they enable the use of larger localized concentrations, enhancing the efficacy of the treatment. Passive-release drug delivery systems, one of the various ways to provide medication, are great inventions. However, they cannot dispense the medication on demand since they are nonprogrammable. Therefore, active actuators are more advantageous in delivery applications. Smart material actuators, however, have greatly increased in popularity for manufacturing wearable and implantable micropumps due to their high energy …
Federated Learning Based Autoencoder Ensemble System For Malware Detection On Internet Of Things Devices, Steven Edward Arroyo
Federated Learning Based Autoencoder Ensemble System For Malware Detection On Internet Of Things Devices, Steven Edward Arroyo
Theses and Dissertations
New technologies are being introduced at a rate faster than ever before and smaller in size. Due to the size of these devices, security is often difficult to implement. The existing solution is a firewall-segmented “IoT Network” that only limits the effect of these infected devices on other parts of the network. We propose a lightweight unsupervised hybrid-cloud ensemble anomaly detection system for malware detection. We perform transfer learning using a generalized model trained on multiple IoT device sources to learn network traffic on new devices with minimal computational resources. We further extend our proposed system to utilize federated learning …
Physical Effects On The Worst-Case Delay Analysis And Signal Integrity Of Buses And Spirals, Mahmoud Mahany
Physical Effects On The Worst-Case Delay Analysis And Signal Integrity Of Buses And Spirals, Mahmoud Mahany
Theses and Dissertations
Physical effects have a significant impact on the IC design which will be investigated in this thesis. Moving toward advanced technology nodes, magnetic effects become more dominant than capacitive effects. As the dimensions of the devices go down and the interconnect manipulates the circuit behavior more and more. Cross talking and voltage drops are affecting the design heavily, however - going to the full electromagnetic point of view - current return path (CRP) adds significant parasitics to the performance of the chip. Neglecting the CRP gives wrong intuition and simulation of the designs, especially that the environment and surroundings can …
Feasibility Of Parallelized Measurement Of Local Thermal Properties, Alexander J. Hansen
Feasibility Of Parallelized Measurement Of Local Thermal Properties, Alexander J. Hansen
Theses and Dissertations
This thesis documents research done in the development and the exploration of feasibility for a high-throughput method to measure local thermal properties. The present capabilities in the measurement of local thermophysical properties such as thermal conductivity, thermal diffusivity, and Kapitza resistance are very inefficient and impractical to fully understand and characterize heat transport through certain materials and features. This work follows up on past work in local thermal property measurement via the spatial domain thermoreflectance (SDTR) method, and explores the possibility of parallelizing the process. The parallelized SDTR (P-SDTR) method involves using laser projector sources to periodically heat and measure …
Infared Light-Based Data Association And Pose Estimation For Aircraft Landing In Urban Environments, David Akagi
Infared Light-Based Data Association And Pose Estimation For Aircraft Landing In Urban Environments, David Akagi
Theses and Dissertations
In this thesis we explore an infrared light-based approach to the problem of pose estimation during aircraft landing in urban environments where GPS is unreliable or unavailable. We introduce a novel fiducial constellation composed of sparse infrared lights that incorporates projective invariant properties in its design to allow for robust recognition and association from arbitrary camera perspectives. We propose a pose estimation pipeline capable of producing high accuracy pose measurements at real-time rates from monocular infrared camera views of the fiducial constellation, and present as part of that pipeline a data association method that is able to robustly identify and …
Control, Localization, And Shock Optimization Of Icosahedral Tensegrity Systems, Brett Layer
Control, Localization, And Shock Optimization Of Icosahedral Tensegrity Systems, Brett Layer
Theses and Dissertations
Exploring the design space of tensegrity systems is the basis of the work presented in this thesis. The areas explored as part of this research include the optimization of tensegrity structures to minimize the size of a tensegrity structure given payload shock constraints, and the control and locomotion of an icosahedral tensegrity system using movable masses and using an accelerometer in conjunction with leveraging geometrical knowledge of an icosahedral tensegrity system to localize the system after the system moves. In the optimization design space, a simplified model was created to represent an icosahedral tensegrity structure. This was done by assuming …
Back To The Future: A Case For The Resurgence Of Approximation Theory For Enabling Data Driven “Intelligence”, Michael Dominic Ciocco
Back To The Future: A Case For The Resurgence Of Approximation Theory For Enabling Data Driven “Intelligence”, Michael Dominic Ciocco
Theses and Dissertations
Artificial Intelligence (AI) has exploded into mainstream consciousness with commercial investments exceeding $90 billion in the last year alone. Inasmuch as consumer-facing applications such ChatGPT offer astounding access to algorithms that were hitherto restricted to academic research labs, public focus of attention on AI has created an avalanche of misinformation. The nexus of investor-driven hype, “surprising” inaccuracies in the answers provided by AI models – now anthropomorphically labeled as “hallucinations”, and impending legislation by well-meaning and concerned governments has resulted in a crisis of confidence in the science of AI. The primary driver for AI’s recent growth is the convergence …
Digitally Beamformed 2d Scanning Phased Array Radar For Networked Unmanned Air Vehicle Detection And Tracking, Carson Reed Brown
Digitally Beamformed 2d Scanning Phased Array Radar For Networked Unmanned Air Vehicle Detection And Tracking, Carson Reed Brown
Theses and Dissertations
Radar systems vary significantly in size, weight, power, and cost (SWaP-C) characteristics with many high SWaP-C models being inaccessible to consumers. Recognizing this, we have engineered an effective but low SWaP-C networked radar system tailored for detecting and tracking unmanned air vehicle (UAV) traffic. Using field-programmable gate arrays (FPGAs), and custom-designed printed circuit boards (PCBs), our system achieves remarkable efficiency without compromising performance. We use patch antennas for our transmitter and in our 4x4 receiver array. With our low SWaP-C system we have successfully concluded outdoor range testing, detecting corner reflector targets at a remarkable 10dB above our noise floor …
Effects Of Print Process Parameters On Droplet-Powder Interaction In Binder Jet Additive Manufacturing, Jacob Lawrence
Effects Of Print Process Parameters On Droplet-Powder Interaction In Binder Jet Additive Manufacturing, Jacob Lawrence
Theses and Dissertations
Binder jet additive manufacturing (BJ) offers unique advantages, including the ability to produce complex geometries and utilize a wide range of materials, but faces challenges related to part quality and defect formation. This thesis investigates the effects of process parameters on droplet-powder interaction, powder relocation, and line formation in BJ printing. A custom BJ test platform was developed to enable precise control over key process parameters and in-situ monitoring. High-speed synchrotron X-ray imaging revealed modes of powder relocation above and below the powder bed surface. Testing revealed that parameters that increase moisture in the powder bed, such as lower droplet …
Study Of Accidental Sliding-Mode Control, April Mary Miller
Study Of Accidental Sliding-Mode Control, April Mary Miller
Theses and Dissertations
The objective of this paper is to examine the Quanser SRV-02 motor servo for the presence of an accidental sliding mode. The SRV-02 is used by undergraduate students to learn basic concepts in controls engineering and will display unexpected sliding mode behavior when its in the “out of box” configuration. To gain a strong background understanding in characteristics of sliding mode, a review of literature on sliding-mode control and sliding mode behavior is completed. Next, a theoretical analysis of the SRV-02 motor servo during the sliding mode is developed. An effort is made to find a Lyapunov function that proves …
The Effects Of Ni Nanoparticle Additives On Thermodynamic Events In Commercial Ni Based Braze Alloy, Cody Lesage
The Effects Of Ni Nanoparticle Additives On Thermodynamic Events In Commercial Ni Based Braze Alloy, Cody Lesage
Theses and Dissertations
The use of nanomaterials in brazing applications has become more prevalent with the increasing understanding of the underlying thermodynamic events during the brazing process. Their influence on an already modified system, via melting point depressants, is not well understood. In this investigation, the influence of both nanoparticle size and weight percent of nanoparticle additive are studied to determine the relationship on thermodynamic events. Differential scanning calorimetry was used to measure the energy flow throughout the system during the brazing events. Scanning electron microscopy was used qualitatively to view the resulting brazed region. The results indicate a direct relationship between nanoparticle …
An Investigation Into In-Flight Loss Of Control Accidents Due To Horizontal Stabilizer Changes On The Piper Cherokee, Connor John Geran
An Investigation Into In-Flight Loss Of Control Accidents Due To Horizontal Stabilizer Changes On The Piper Cherokee, Connor John Geran
Theses and Dissertations
Loss of Control (LOC) while in-flight in General Aviation (GA) has been the subject of intense research by academic institutions and regulatory agencies in recent years [4] [9] [11] [19] [20] [21]. This interest is primarily due to a disproportionate number of all aircraft accidents occurring within the GA category of flight, with 94% of accidents in 2022 occurring within GA, caused primarily by pilot LOC, with 42% of accidents having LOC as the listed cause. Research into this subject at FIT yielded the results that many common GA aircraft tend to experience a strong pitch up response after undergoing …
Selecting Industry 4.0 Technologies For Construction Activities Using Clustering Analysis And Text Mining, Benyamin Sadeghi
Selecting Industry 4.0 Technologies For Construction Activities Using Clustering Analysis And Text Mining, Benyamin Sadeghi
Theses and Dissertations
Construction 4.0, which involves the application of Industry 4.0 technologies in construction activities, promises to revolutionize the construction industry by improving productivity, enhancing safety, promoting sustainability, and strengthening quality in the age of the Information Revolution. Industry 4.0 technologies such as Artificial Intelligence (AI), robotics, and the Internet of Things (IoT), have the potential to radically transform the construction industry in the 21st century. Construction activities constitute approximately 4.3% of the US gross domestic product-GDP and account for creating 7.5 million jobs. Although productivity has significantly increased in other industries, progress has been slow in the construction sector. One contributing …
Microwave Imaging Technique For Breast Cancer Detection, Nure Alam Chowdhury
Microwave Imaging Technique For Breast Cancer Detection, Nure Alam Chowdhury
Theses and Dissertations
Breast cancer is a global problem, and it is inevitable to detect cancerous cells at early stages. In recent years, microwave imaging technology has been widely applied in biomedical applications for its non-ionizing radiation. In this study, we design a micro-strip patch antenna with an inverted T-type notch in the partial ground to detect tumor cells inside the human breast. The size of the current antenna is small enough (18 mm × 21 mm × 1.6 mm) to distribute around the breast phantom. The operating frequency has been observed from 6–14 GHz with a minimum return loss of −61.18 dB …
The Effect Of Extended Saltwater Absorption And Uv Cure On The Compressive Properties Of Msla 3d-Printed Photopolymer Resin Samples With Printing Variations, Suzanne Dixon
Theses and Dissertations
Liquid Crystal Display (LCD) 3D printers, also known as Masked Stereolithography Apparatus (MSLA), is a type of vat polymerization printing technique that cures liquid resin into a solid object. This technique is relatively new. Consequently, there is a shortage of detailed research on the impact of long-term environmental exposure on the MSLA-printed materials. The research within this document informs engineers and scientists of resin compressive properties after extended exposure to saltwater and ultraviolet (UV) light. Saltwater absorption of the material was analyzed at atmospheric pressure, 30-psi, 60-psi, and 90-psi; the samples reached saturation in saltwater after 56 days. The variation …
Test And Evaluation Model For Midwater Docking Of Autonomous Underwater Vehicles, Parker Baillon
Test And Evaluation Model For Midwater Docking Of Autonomous Underwater Vehicles, Parker Baillon
Theses and Dissertations
This research created a Test and Evaluation (T&E) model for midwater Autonomous Underwater Vehicle (AUV) capture. The creation of this model will allow for a better assessment of the feasibility of midwater AUV capture. To achieve this, the T&E model was exposed to various flow conditions to assess stability. Capturing an AUV in midwater, the area below the wave-affected zone to the sea floor, has many benefits for an AUV and its mission. AUVs basing missions from a midwater dock will not be affected by wave motions. A midwater dock can be transported to any mission site and deployed with …
Amazon Fba Vs Fbm; A Strategic Approach To Determine Which Method Can Effectively Utilize Project Management Principles To Enhance Your Success As A New Amazon Seller., Tiffany Renee White
Amazon Fba Vs Fbm; A Strategic Approach To Determine Which Method Can Effectively Utilize Project Management Principles To Enhance Your Success As A New Amazon Seller., Tiffany Renee White
Theses and Dissertations
Navigating the complexities of a platform such as Amazon demands a strategic approach guided by project management principles. A comparative analysis of Fulfillment by Amazon (FBA) and Fulfillment by Merchant (FBM) methods were completed by focusing on how project management principles optimize product acquisition, supply chain management, and shipping methods for Amazon sellers. The objectives of this study included the identification of top product acquisition tools, the evaluation of inventory management software, assessing shipping methods, and determining the most effective fulfillment process for Amazon seller success. A mixed-methods approach was applied, involving an Amazon seller survey, literature review, data analysis, …
High-Fidelity 3d Reconstruction Of Space Bodies Using Machine Learning And Neural Radiance Fields, Timothy Jacob Huber
High-Fidelity 3d Reconstruction Of Space Bodies Using Machine Learning And Neural Radiance Fields, Timothy Jacob Huber
Theses and Dissertations
In the era of burgeoning space exploration, the growing population of spacecraft heightens the inevitability of collisions. While traditional imagery remains effective for damage assessment, its lack of 3D representation of the object necessitates more advanced approaches. This research delves into cutting-edge methodologies, with a primary focus on leveraging machine learning and computer vision technologies to enhance the precision and efficiency of damage assessment by taking imagery of a space body and creating a 3D model. The study extensively investigates TransMVSNet, a neural network code employing classical computer vision techniques such as multi-vision stereo (MVS) and depth maps. This approach …
Analysis Of The Temperature Dynamics In General Aviation Brake System, Rajnea Anthony Coley
Analysis Of The Temperature Dynamics In General Aviation Brake System, Rajnea Anthony Coley
Theses and Dissertations
As aircraft brakes are subjected to intense heat generation during landings and braking maneuvers, comprehending the temperature dynamics is essential for ensuring optimal performance, longevity, and, most importantly, the safety of flight operations. This paper dives into understanding heating and cooling in the brake systems of the Piper Aircraft PA28. In order to investigate the thermal behavior of aircraft brake components, this study evaluates a variety of general aviation braking scenarios, from light to heavy braking, including stop-and-go landings, full-stop taxi backs, and continuous braking while taxiing. It was noticeable that light braking exhibits slight temperature increases and cooling rates. …
Experimental And Numerical Analysis Of Laminar And Transitional Flow Through Annular Corrugated Pipes, Joseph Russell Sargent
Experimental And Numerical Analysis Of Laminar And Transitional Flow Through Annular Corrugated Pipes, Joseph Russell Sargent
Theses and Dissertations
This dissertation presents studies on pressure loss through annular corrugated pipes to determine a friction factor coefficient using nitrogen. Ten different corrugated pipes’ geometries were evaluated via testing and experimentation. The ratio of corrugation height to inner diameter varied from 0.233 to 0.333 and the ratio of corrugation pitch to inner diameter varied from 0.181 to 0.446. Nitrogen flow rates between 0.25 to 94.4 standard liters per minute were used, resulting in Reynolds numbers, based on the corrugated pipe inner diameter, from 100 to 23,000. The experimental set-up was validated using smooth-pipe pressure loss measurements and the derived friction factor …
Investigating Potential Improvements To Mbse Software To Support Dodaf, Jennifer Marie Kimpson
Investigating Potential Improvements To Mbse Software To Support Dodaf, Jennifer Marie Kimpson
Theses and Dissertations
The integration of models created through model-based systems engineering methods with DoDAF is not a new concept. By creating DoDAF-aligned models, DoD program managers are following DoD guidelines to hopefully achieve more effective communication with stakeholders and improve efficiency of their programs. With the use of MBSE tools to create these models, DoD program managers are able to take further advantage of the benefits of MBSE methods. However, even with the use of MBSE tools, there continue to be issues throughout DoD programs. The literature has shown that a continuous improvement approach regarding the use of MBSE tools with DoDAF …
Evaluation Of Beach-Fx — Beach Nourishment Planning Model – Miami Beach Case Study, Brennan Chase Banks
Evaluation Of Beach-Fx — Beach Nourishment Planning Model – Miami Beach Case Study, Brennan Chase Banks
Theses and Dissertations
Miami Beach, located on the Southeast coast of Florida, is a concerning location for coastal erosion because of the increasing intensity and frequency of tropical storms, nuisance flooding, and accelerated sea-level rise due to climate change. Miami Beach is famous for its beautiful beaches, making it a location of high interest for tourists, citizens, and investors. It is vital for coastal practitioners to accurately model coastal processes, beach evolution, and storm damage during the planning stage of coastal protection projects. The U.S. Army Corps of Engineers developed the Beach-fx model as a tool for engineers, planners, and economists to …
Deep Learning System Identification, Linearization And Control Of Dynamical Systems Utilizing Koopman Theory With Applications In Orbital Systems, George Mario Nehma
Deep Learning System Identification, Linearization And Control Of Dynamical Systems Utilizing Koopman Theory With Applications In Orbital Systems, George Mario Nehma
Theses and Dissertations
The computational and complexity burden of current linearization techniques is one that is a hinderance in the application of real world guidance, navigation and control systems. With the advancements in Deep Neural Networks, large data handling and Koopman Theory, the possibility of global linearizations of nonlinear systems is more prominent. This work demonstrates the capability of a Deep Neural Network learned Koopman operator to transform a nonlinear system into a Linear Time-Invariant system. The method presented is applied to both two purely dynamical systems and one controlled system to emphasize the ability for the technique to be applied in all …
Ai-Powered Information Retrieval In Meeting Records And Transcripts Enhancing Efficiency And User Experience, Srushti Nitin Ghadge
Ai-Powered Information Retrieval In Meeting Records And Transcripts Enhancing Efficiency And User Experience, Srushti Nitin Ghadge
Theses and Dissertations
This study compares the traditional search methods, which is to search from video recordings of the meetings by moving the slider back and forth or by keyword search in transcripts versus integrated AI video plus transcript search. Based on the previous test results, we introduced some human-centric design features to the AI and built a new enhanced AI search tool for information retrieval. For search technique efficiency testing, the method had two set of experiments. The first results of the experiment showed that AI-based search algorithms were more accurate and faster than conventional search approaches. Participants were also happier with …
Computational Fluid Dynamics Study Of Perforated Monopiles, Mary Kathryn Walker
Computational Fluid Dynamics Study Of Perforated Monopiles, Mary Kathryn Walker
Theses and Dissertations
Monopiles are used in the construction of offshore wind turbines and typically have a design life of 25 to 50 years. Over their lifecycle, monopiles are exposed to a corrosive saltwater environment, facilitating a galvanic oxidation process that quickly degrades the structure. This process can be mitigated by coating the monopile in a protective barrier and implementing cathodic protection techniques. Historically, monopile designers assumed the interior of the pile would be completely sealed and the galvanic corrosion process would eventually consume all the available oxygen, halting the reaction. However, penetrations made in the pile wall for conduit often leaked and …
The Advancement Of Experimental And Computation Tools For The Study Of Molten Salt Chemistry To Facilitate The Extraction Of Strategic Elements In Nuclear Applications, Michael Stoddard
Theses and Dissertations
Nuclear energy presents environmental benefits, yet the challenge of radioactive waste management persists. Advanced solutions, such as Molten Salt Reactors (MSRs), require a more profound understanding of molten salt chemistry. This research aims to develop tools, including a depletion simulator, molten salt electrochemical simulator, and a fluoride-based thermodynamic reference electrode for electrochemical purification. The computationally inexpensive depletion simulator allows for exploration into extraction and processing strategies for molten salt reactors. An illustrative case study on Mo-99 production from MSRs demonstrates the practical application of the theoretical framework, emphasizing the need for optimization in extraction effectiveness and separation difficulty. The electrochemical …
Development Of Deployable Arrays For Satellites Through Origami-Pattern Design, Modeling, And Optimization, Nathan Mckellar Coleman
Development Of Deployable Arrays For Satellites Through Origami-Pattern Design, Modeling, And Optimization, Nathan Mckellar Coleman
Theses and Dissertations
This research presents methods for modeling and optimizing an origami design using compliant mechanisms, improving origami design processes, modeling and analyzing rolling behavior of compliant designs, and an antenna design for SmallSats. A framework for the optimization of the origami Flasher pattern to mitigate issues with rigid-foldability is shown, and several optimization solutions are presented to overcome these issues. An alternative design method is presented which allows designers to more accurately predict the characteristics of a design in the deployed state, and configurations are shown for an example use case. A model for rolled gossamer structures is presented which predicts …
Towards A Practical Method For Monitoring Kinetic Processes In Polymers With Low-Frequency Raman Spectroscopy, Robert Vito Chimenti
Towards A Practical Method For Monitoring Kinetic Processes In Polymers With Low-Frequency Raman Spectroscopy, Robert Vito Chimenti
Theses and Dissertations
Unlike liquids and crystalline solids, glassy materials exist in a constant state of structural nonequilibrium. Therefore, a comprehensive understanding of material kinetics is critical for understanding the structure-property-processing relationships of polymeric materials. Amorphous materials universally display low-frequency Raman features related to the phonon density of states resulting in a broad disorder band for Raman shifts below 100 cm-1, which is related to the conformational entropy and the modulus. This disorder band is dominated by the Boson peak, a feature due to phonon scattering because of disorder and can be related to the transverse sound velocity of the material, and a …
Laboratory Evaluation Of Early-Age Concrete Comprising Type Il Cement And Natural Pozzolans, Battsagaan Ilch
Laboratory Evaluation Of Early-Age Concrete Comprising Type Il Cement And Natural Pozzolans, Battsagaan Ilch
Theses and Dissertations
The objective of this laboratory research was to investigate the effects of a higher water-cementitious materials ratio on selected properties of concrete mixtures comprising natural pozzolans. The scope of work included testing of six concrete mixtures, including one for each of three natural pozzolans at two water-cementitious materials ratios of 0.44 and 0.48 and one concrete mixture without pozzolan at a water-cementitious materials ratio of 0.44, which was treated as a baseline in this research. The stiffness and strength of each concrete mixture were measured at 1, 3, and 7 days using concrete specimens that were cast immediately after mixing. …