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Articles 20731 - 20760 of 196368

Full-Text Articles in Engineering

Study Of A Multi-Agent Containment Problem Under Communication Constraints And Defense From Malicious Agents, Braulio Mora Jan 2024

Study Of A Multi-Agent Containment Problem Under Communication Constraints And Defense From Malicious Agents, Braulio Mora

Mechanical and Aerospace Engineering Theses - Archive

This thesis investigates a multi-agent containment problem where a fast evader, moving at a constant speed and heading, attempts to escape a circular containment region. A team of slow pursuers possess a nonzero capture radius and seek to capture the evader before escape. The research addresses two primary scenarios: one involving the team of pursuers, with no communication network, being constrained to the edge of the containment region, and the second involving a team of pursuers, with a communication network, not being constrained to the edge of the containment region. Both scenarios study the influence of malicious agents in the …


Nonlinear Guidance And Control Of Unmanned Aerial Manipulators For Delivering A Payload On A Moving Platform, Ravi Gyawali Jan 2024

Nonlinear Guidance And Control Of Unmanned Aerial Manipulators For Delivering A Payload On A Moving Platform, Ravi Gyawali

Mechanical and Aerospace Engineering Theses - Archive

Unmanned Aerial manipulators (UAMs) are a class of Unmanned Aerial Vehicles (UAVs) equipped with a manipulator. By combining the aerial mobility of a UAV with a manipulator's dexterity, these hybrid systems can perform a wide range of complex tasks while reducing risks and costs. As a result, they are increasingly being utilized for military, industrial, and agricultural applications.

The thesis presents a novel approach for a multi-UAM system to collaboratively deliver a payload on a stationary or maneuvering platform. A sliding-mode-based guidance law, sourced from existing literature, is integrated with a combined control technique for the UAVs and their respective …


Image-Based Thermal And Mechanical Analysis Of Polymers, Yukti Shinglot Jan 2024

Image-Based Thermal And Mechanical Analysis Of Polymers, Yukti Shinglot

Mechanical and Aerospace Engineering Theses - Archive

In recent years, application of polymers have rapidly expanded across industries due to their versatility, cost-effectiveness, and adaptability to diverse manufacturing techniques, including 3D printing. Innovations in PolyJet technology enable the creation of complex geometries with tailored color combinations, transparency, and flexibility, broadening applications in medical, aerospace, and automotive sectors. Advances in processing viscoelastic rubbers like PDMS (Polydimethylsiloxane) have further enhanced its mechanical properties, expanding its use in biomedical devices and electronic components. However, polymers are susceptible to complex deformation and failure under thermal and mechanical stresses, which can impact their performance and safety. This research examines the thermal behavior …


Electophorectic Deposition For Novel Nanodecorated Electrodes Towards Thermally Charging Supercapacitor (Tcsc), Ashish Thakur Jan 2024

Electophorectic Deposition For Novel Nanodecorated Electrodes Towards Thermally Charging Supercapacitor (Tcsc), Ashish Thakur

Mechanical and Aerospace Engineering Theses - Archive

Thermally Self-Charging Supercapacitors (TSCS) are a promising new technology that can harvest waste heat to produce electrical energy. The Soret effect is exploited wherein ion separation due a temperature gradient leads to a potential difference. Here, we use electrophoretic deposition (EPD), a room-temperature, scalable, universal technique, to obtain CNT decorated electrodes for fabrication of such TSCS devices with ionic liquid electrolyte. We further show that precise control over deposition parameters can be used for optimization of TSCS performance metrics. TSCS devices were tested by several characterization standards, indicating the superior performance of nanodecorated electrodes obtained by EPD.


Thermal Damage And Mechanical Failure Analysis Of Polymers, Tina Ko Jan 2024

Thermal Damage And Mechanical Failure Analysis Of Polymers, Tina Ko

Mechanical and Aerospace Engineering Theses - Archive

As the demand for more intricate and precise components increases, polymers continue to stand out for their flexibility, durability, and adaptability across numerous applications. From aerospace to biomedical engineering industries, polymers are valued for their versatility and customizability, enabling the creation of complex geometries or achieving specific material properties. Since polymers are widely used, analyzing their thermal and mechanical properties is essential to understand their behavior under high-energy exposure or defects. Two types of polymers were analyzed: Polydimethylsiloxane (PDMS) and 3D-printed digital materials. This thesis investigates the mechanical and thermal response of polymers through two distinct studies. The first part …


Dynamics Of Separated Flows In Diffusers With Vortex Generators, Sandeep Eldho James Jan 2024

Dynamics Of Separated Flows In Diffusers With Vortex Generators, Sandeep Eldho James

Mechanical and Aerospace Engineering Dissertations - Archive

Flow through curved diffusers is complicated due to the possibility of flow separation and secondary flows. Vortex generators (VGs) are a class of passive flow separation control devices used to improve the flow quality in curved diffusers by suppressing flow separation. However, the literature review demands an in-depth investigation on the physical mechanisms related to flow separation control. Thus, this study aims to improve the understanding of the underlying flow physics associated with VG-induced flow separation control in confined flows. The chosen geometry for this study is a well-documented asymmetric diffuser which exhibits a mild flow separation.

The theoretical formulation …


Generalizable Fugitive Carrier Method For 3d Printing Of Hydrogels, Hakan Arslan Jan 2024

Generalizable Fugitive Carrier Method For 3d Printing Of Hydrogels, Hakan Arslan

Mechanical and Aerospace Engineering Dissertations - Archive

Hydrogels, with physical characteristics resembling biological soft tissues, hold great potential for bioinspired and biomedical applications. However, using them in additive manufacturing systems has challenges because of their poor mechanical and rheological properties. In response to these challenges, we introduce a fugitive carrier method, a novel and generalizable approach for materials incompatible with pneumatic-based extrusion three-dimensional (3D) printers. Our developed fugitive carrier method allows the 3D printing of a broad spectrum of hydrogel precursors with low viscosity while retaining their inherent properties. This technique has been successfully demonstrated by creating biomimetic structures with anisotropic and programmable systems utilizing temperature-sensitive hydrogel …


Quantitative Modeling Of Micro Discharge And Oxide Growth In Plasma Electrolytic Oxidation Of Titanium, Kingsley I. Ochiabuto Jan 2024

Quantitative Modeling Of Micro Discharge And Oxide Growth In Plasma Electrolytic Oxidation Of Titanium, Kingsley I. Ochiabuto

Material Science and Engineering Dissertations - Archive

Plasma electrolytic oxidation (PEO) has been extensively applied in the past to improve the tribological properties of titanium and its alloys allowing their widespread use in industrial applications. However, the complete PEO mechanism of action remains unclear. While there are several mathematical models providing useful insights into the PEO process, they do not fully incorporate the effect of applied potential on the outcomes of PEO. In this work, we develop an experimentally informed computational model by expanding on the dielectric breakdown model. We incorporate experimental data to extract key parameters, exploring the iterative dependency of the oxide thickness and ionic …


Machine Learning-Based Methodology For Multi-Objective And Multi-Design Variable Optimization Of Finned Heat Sinks And Evaluation Of Electrochemical Additive Manufactured Heat Sink Designs For Single-Phase Immersion Cooling, Joseph F. Herring Ii Jan 2024

Machine Learning-Based Methodology For Multi-Objective And Multi-Design Variable Optimization Of Finned Heat Sinks And Evaluation Of Electrochemical Additive Manufactured Heat Sink Designs For Single-Phase Immersion Cooling, Joseph F. Herring Ii

Mechanical and Aerospace Engineering Dissertations - Archive

Traditional air-cooling along with corresponding heat sinks are beginning to reach performance limits, requiring lower air-supply temperatures and higher air-supply flowrates, in order to meet the rising thermal management requirements of high power-density electronics. A switch from air-cooling to single-phase immersion cooling provides significant thermal performance improvement and reliability benefits. When hardware which is designed for air cooling is implemented within a single-phase immersion cooling regime, optimization of the heat sinks provides additional thermal performance improvements. This work investigates performance of a machine learning (ML) approach to building a predictive model of the multi objective and multi-design variable optimization of …


Investigating Urban Impacts On Temperature And Rainfall Using Drone, Radar And Machine Learning Techniques, Junaid Ahmad Jan 2024

Investigating Urban Impacts On Temperature And Rainfall Using Drone, Radar And Machine Learning Techniques, Junaid Ahmad

Civil Engineering Dissertations - Archive

The global urban population is increasing, and it is anticipated that approximately 70% of people will reside in urban areas by 2050. Urbanization changes land use and land cover, altering local climatology. For example, various urban centers across the globe are experiencing extreme rainfall events, resulting in widespread damage to life and property with possible linkages to urbanization. The use of artificial materials in urban areas brings significant changes to the surface temperatures. Due to the high heat capacity of most of the construction materials, the temperature of the urban area can increase substantially compared to the rural areas. This …


Human System Composite Performance Measures: General Systems Performance Theory Insights, Lawrence Disalvi Jan 2024

Human System Composite Performance Measures: General Systems Performance Theory Insights, Lawrence Disalvi

Bioengineering Dissertations - Archive

Composite Performance Measures (CPMs) of human performance are widely employed in applications that range from mundane to life-changing, yet they are frequently presented without explanation or reference to theoretical underpinnings. The conceptual soundness of a widely used CPM approach, based on additive combination of constituent components, has been called into question by Kondraske. He argues the relevance of General Systems Performance Theory (GSPT) and performance capacity envelope concepts when applied to multidimensional CPM measures.

To obtain evidence-based answers to assertions regarding CPM types and rationale employed in medical and non-medical contexts, a Systematic Descriptive Review was conducted. Separately, the GSPT-based …


Algorithm Development For Analysis Of Optical Time-Series Data Generated By Biomodal Optical-Electrical Nanopore Sensor, Yu-Shiuan Huang Jan 2024

Algorithm Development For Analysis Of Optical Time-Series Data Generated By Biomodal Optical-Electrical Nanopore Sensor, Yu-Shiuan Huang

Bioengineering Theses - Archive

Nanopore biosensors have played an essential role in the scientific investigation of DNA, RNA, proteins, and other bio-analytes. Traditional nanopore biosensors detect variations in electrical current conductance caused by the analyte blocking the current passing transiently through a nano-sized aperture, i.e., the nanopore. This electrical data provides information about the amount of current blockage when the analyte is inside the nanopore and the time it takes for analytes to travel through the nanopore (translocation time). The translocation time of analytes in standard nanopore measurements is typically very short, usually tens of microseconds, limiting the accuracy of measuring the analytes’ characteristics. …


Computational And Experimental Analysis Of Silica Nanoparticles Under Dc And Ac Electric Fields Using A Self-Induced Back Action Actuated Nanopore Electrophoresis (Sane) Sensor, Homayoun Asadzadeh, Scott Renkes, George Alexandrakis, Minjun Kim, Scott Turpin Jan 2024

Computational And Experimental Analysis Of Silica Nanoparticles Under Dc And Ac Electric Fields Using A Self-Induced Back Action Actuated Nanopore Electrophoresis (Sane) Sensor, Homayoun Asadzadeh, Scott Renkes, George Alexandrakis, Minjun Kim, Scott Turpin

Bioengineering Dissertations - Archive

In this dissertation I have studied a novel single-molecule nanosensor that integrates a Solid-State Nanopore (SSNP), milled in silicon nitride with a Double Nanohole (DNH) nanoaperture, milled in gold. This device leverages Self-Induced Back-Action (SIBA) for optical trapping with ssNP electrical sensing and is called the SIBA-Actuated Nanopore Electrophoresis (SANE) sensor. My lab has previously shown that simultaneous acquisition of bimodal optical and direct current (DC) electrical signatures enables more detailed characterization of nanoscopic analytes compared to using electrical data alone, which are typically collected by ssNP sensors. In this work I have first studied by COMSOL Multiphysics simulations the …


Spray-On Sensor Formulations That Enable Detection Of Physical And Chemical Stimuli, Priyanka Shiveshwarkar Jan 2024

Spray-On Sensor Formulations That Enable Detection Of Physical And Chemical Stimuli, Priyanka Shiveshwarkar

Bioengineering Dissertations - Archive

Polydiacetylene based materials have been used for a variety of liquid phase sensing applications. There remains a need for low cost, easy-to-read gas phase sensors for continuous monitoring of physiological parameters and environmental hazards at work or at home. Such sensors could have applications in everyday life, for example as point-of-care or at home testing devices to enable early detection of disease to reduce healthcare costs. Making accessible and non-invasive technologies for monitoring of health and health risks provides individuals with the ability to be proactive in regard to their health and safety. In other examples, environmental monitoring systems could …


Development Of Anti-Microbial Nanocoatings On Metallic Surfaces To Prevent Infections, Luis Fernando Soto Garcia Jan 2024

Development Of Anti-Microbial Nanocoatings On Metallic Surfaces To Prevent Infections, Luis Fernando Soto Garcia

Bioengineering Dissertations - Archive

Healthcare-associated infections have a prevalence of about 7% in the United States and up to 50% in some developing nations. They not only present a constant risk for inpatients and healthcare workers but are also a serious challenge to human health services worldwide. These infections can be transmitted via contaminated non-critical surfaces like doorknobs and bedrails, which are routinely cleaned with low-level disinfectants approved by the U.S. Environmental Protection Agency. However, this strategy has limited efficacy since recontamination occurs, resulting in these surfaces again becoming vectors of infection. In this work, we addressed this issue by developing a self-disinfecting nanocomposite …


Evaluation Of Air Emissions For Cured-In-Place Pipe Construction Method For Sewer Pipe Rehabilitation, Rasoul Adnan Abbas Jan 2024

Evaluation Of Air Emissions For Cured-In-Place Pipe Construction Method For Sewer Pipe Rehabilitation, Rasoul Adnan Abbas

Civil Engineering Dissertations - Archive

The aging underground pipelines in the United States, which include sewer and water supply systems, have exceeded their design lifespan and will have to be renewed or replaced to continue providing these vital services to communities. Two methods can be used to replace the pipes: open-cut and trenchless technologies. Trenchless methods offer several advantages in urban areas: a small work area, lower operational and maintenance costs, and fewer negative impacts on the surrounding communities. Among the trenchless options, the CIPP method has been chosen for this research since it minimizes surface disruption, making it particularly well-suited for densely populated areas …


Sustainable Use Of Wastewater In Concrete Construction, Mohammadamin Soltanianfard Jan 2024

Sustainable Use Of Wastewater In Concrete Construction, Mohammadamin Soltanianfard

Civil Engineering Dissertations - Archive

This dissertation investigates the use of wastewater from various treatment stages in concrete production to promote sustainable construction practices. Concrete prepared with potable water (PW) served as a control, while wastewater from plant final effluent (FE), chlorine contact basin (CL), secondary clarifier effluent (SC), primary clarifier effluent (PC), and bar screen effluent (BSE) was evaluated.

A comprehensive testing program was implemented to assess performance, including compressive strength tests, water absorption measurements, X-ray diffraction (XRD) analysis, thermogravimetric analysis (TGA), and scanning electron microscopy (SEM). Results showed that wastewater from advanced stages (FE, CL, SC) had minimal impact on strength and durability, …


Net-Zero Home Race: Gamification For Learning Energy Consumption Merit, Terry E. Payne Jan 2024

Net-Zero Home Race: Gamification For Learning Energy Consumption Merit, Terry E. Payne

Civil Engineering Theses - Archive

Buildings have contributed significantly to carbon emissions over the past decades, amplified by rapid construction growth. To address this, sustainable concepts like energy efficiency and financial planning for home retrofitting have become essential in promoting environmentally conscious practices. NZHR was created as a gamified experience to help bridge the gap between education and motivational enjoyment. Testing the game demonstrated participants' ability to learn and understand the importance of strategic thinking with home retrofit upgrades. Gamification principles such as the Octalysis and Bartle test were incorporated into the design process to construct a well-rounded game that provides intrinsic and extrinsic principles. …


Experimental And Finite Element Investigation Of Shear Transfer Mechanisms And Capacity Of Continuous Post-Tensioned Concrete Beams In One-Way Slab Buildings, Suman Rijal Jan 2024

Experimental And Finite Element Investigation Of Shear Transfer Mechanisms And Capacity Of Continuous Post-Tensioned Concrete Beams In One-Way Slab Buildings, Suman Rijal

Civil Engineering Theses - Archive

This study investigates the shear behavior and resistance mechanisms of continuous post-tensioned beams commonly used in one-way slab buildings. Combining experimental and analytical methods, the research focuses on the targeted failure regions of prestressed and non-prestressed continuous beams to gain deeper insights into their shear behavior. The large-scale specimens used in this study featured realistic parabolic tendon profiles and an average prestress level comparable to that used in actual construction. The experimental program includes three test series, with beam designs and setups refined for each series based on observations of shear crack development and progression in the preceding series. This …


Assessing The Seismic Performance Of 45 Ft And 65 Ft Special Truss Moment Frames (Stmfs) Designed With Proposed 2027 Aisc Seismic Provisions Using Nonlinear Time-History Analysis, Vesal Shakibaie Jan 2024

Assessing The Seismic Performance Of 45 Ft And 65 Ft Special Truss Moment Frames (Stmfs) Designed With Proposed 2027 Aisc Seismic Provisions Using Nonlinear Time-History Analysis, Vesal Shakibaie

Civil Engineering Theses - Archive

This thesis presents a comprehensive investigation into the seismic design and performance of Special Truss Moment Frames (STMFs) with long spans, focusing on two configurations: STMFs with Vierendeel panels and those with X-braced diagonals in the special segment. The study assesses two case studies with spans of 45 ft and 65 ft, analyzing their behavior under Design Basis Earthquake (DBE) and Maximum Considered Earthquake (MCE) scenarios. The structures were designed according to the latest proposed 2027 revision of the AISC Seismic Provisions, which includes significant changes compared to the published 2022 version. Nonlinear time-history analysis and nonlinear static (push-over) analysis …


Generating Blood Analog For Laser Induced Fluorescent Particle Image Velocimetry, Chungyiu Ma, Jared Chong, Hang Yi, Zifeng Yang, Luke Bramlage, Bryan Ludwig Jan 2024

Generating Blood Analog For Laser Induced Fluorescent Particle Image Velocimetry, Chungyiu Ma, Jared Chong, Hang Yi, Zifeng Yang, Luke Bramlage, Bryan Ludwig

Mechanical and Materials Engineering Faculty Publications

To mimic blood non-Newtonian viscosity features under designated temperatures from 305 to 315 K, transparent blood analogs were generated by the mixture of xanthan gum and deionized water with fluorescent particles for laser induced fluorescent particle image velocimetry.


Planning Innovation For Implementing Modular Prefabricated Construction In Housing Development In Indonesia Using A Risk-Based Iso 56002:2019 Approach To Improve Project Performance, Deansa Agya Rahman, Yusuf Latief Jan 2024

Planning Innovation For Implementing Modular Prefabricated Construction In Housing Development In Indonesia Using A Risk-Based Iso 56002:2019 Approach To Improve Project Performance, Deansa Agya Rahman, Yusuf Latief

Smart City

The development of housing in Indonesia, growing rapidly due to urbanization and population growth, faces challenges in terms of land, labor, and housing backlog. Despite being innovative, modular prefabrication methods are limited by unattractive designs and high costs, slowing down construction, harming the productivity of construction companies, and hindering the growth of the national construction sector. These challenges are prevalent in various countries and are influenced by low knowledge, conservative mindsets, and inhibiting regulations. In Indonesia, additional issues include a lack of mastery of modular prefabrication methods and awareness of long-term benefits. This research identified innovative risk-based applications of modular …


Articulating Balsa Wood Bridge, Cole Blevins Jan 2024

Articulating Balsa Wood Bridge, Cole Blevins

All Undergraduate Projects

The objective of this project was to design and construct an articulating bridge consisting of only balsa wood and glue to meet a set of given requirements. The main requirements include a maximum bridge weight, minimum load to be supported, and a minimum height that the bridge must raise to utilizing an electric motor.

To meet the objective of the project, a series of engineering analyses were completed to determine suitable dimensions and geometry for each component of the bridge and articulation structure. Before conducting analyses for the bridge, a few different truss structures were considered including a Pratt truss, …


Rc Baja: Drivetrain And Chassis, Caden Harris Jan 2024

Rc Baja: Drivetrain And Chassis, Caden Harris

All Undergraduate Projects

The engineers in the CWU Mechanical Engineering Technology program were asked to design and manufacture a remote-controlled Baja car to compete in several different events. The car was required to compete in a drag race, slalom event, and Baja event against other cars created by engineering students. To compete at the highest level, the cars needed to finely balance ruggedness, weight, torque, and top speed.

This report is dedicated to the designing, manufacturing, and testing of the drivetrain and chassis that supported the RC car as it competed in the school-sanctioned competition; a partner was responsible for the steering and …


Rc Baja: Suspension And Steering, Daniel Davis Jan 2024

Rc Baja: Suspension And Steering, Daniel Davis

All Undergraduate Projects

Engineers enrolled in the Mechanical Engineering Technology program at Central Washington University were tasked with developing a vehicle to compete in the ASME Baja competition. The engineers were in teams of two, one focused on suspension and steering and the other focused on drive train and chassis.

To begin the design of the vehicle, engineering analyses were completed on each of the components to comply with the requirements set by the team. After completion of multiple analyses for the components of the vehicle, the dimensions were validated and have been created in a CAD program to allow for virtual assembly …


Rc Baja: Drivetrain & Chassis, Ahmad Adam Jan 2024

Rc Baja: Drivetrain & Chassis, Ahmad Adam

All Undergraduate Projects

The project's primary aim is to employ engineering techniques in the design and construction of an RC Baja car, ensuring the chassis and drivetrain are sufficient for participation in the ASME RC Baja competition. The suspension and steering system were entrusted to a teammate to contribute to the project's success.

In approaching this problem, various analyses were conducted during fall quarter, in deciding the design of the RC car. For example, one analysis established the necessary output power to attain a maximum speed of 25 miles per hour within a 15-second timeframe. The analysis employed acceleration and power equations …


Nasa Rocket Payload Airfoil Deceleration, Brycen Geck Jan 2024

Nasa Rocket Payload Airfoil Deceleration, Brycen Geck

All Undergraduate Projects

NASA Student Launch Initiative gave a requirement that a lander must descend to the ground from a height of 400-800 feet with predetermined human survivability without using parachute or streamers. Around sixty colleges were chosen from around the United States to compete in competition. This competition and data taken will help innovate the rocket and lander programs in full scale space exploration in the future.

Design of the payload involved intensive design, testing and aerodynamic analysis. Majority of the manufacturing revolved around 3D printing, aluminum 5051 sheet and carbon fiber vacuum bagging. PLA and PETG was used on components which …


Articulating Balsa Wood Bridge, Nate Harris Jan 2024

Articulating Balsa Wood Bridge, Nate Harris

All Undergraduate Projects

This report describes the design, construction, and testing of a small-scale articulating balsa wood bridge that allowed passage over normally impassable terrain. The bridge was required to span a 400mm gap, while also articulating the midpoint of the bridge 140mm above its resting position. The bridge also needed to support a 20kg (44 lbs.) point load in the center of the bridge, and the bridge and articulation tower together needed to weigh less than 85 (0.19 lbs.) grams.

To construct the bridge, statics and mechanics of materials was used to design a truss that was calculated to support the load …


Articulating Balsa Wood Bridge, Samuel K. Katsuda Jan 2024

Articulating Balsa Wood Bridge, Samuel K. Katsuda

All Undergraduate Projects

The objective of this project was to design, construct and test an articulating balsa wood bridge. It needed to fit certain requirements such as maintaining the bridge structure and articulation structure weight under 85g, being able to articulate 140mm, and be able to withstand a load of 20kg at the middle. The aim was to both create a product, but also give the student a chance to demonstrate their practical knowledge in engineering and going through the processes.

To complete this project as mentioned the student began by creating an initial design and performing a series of analyses on the …


The Tortuga Drivtrain And Chassis Rc Baja, Roberto C. Vieyra Avalos Jan 2024

The Tortuga Drivtrain And Chassis Rc Baja, Roberto C. Vieyra Avalos

All Undergraduate Projects

The students in charge of the project, seniors at Central Washington University were tasked with the design and manufacturing of the RC Baja to compete in the Slalom and Sprint event and the Baja event where the maneuverability and acceleration are demonstrated. The project was divided between Roberto, in charge of the drivetrain and chassis and Rogelio, in charge of the steering and suspension. There were also various requirements like velocity and deflection, ensuring the device reaches 30mph and keeping the deflection of components to a minimum and many others which can be seen in section D of the introduction. …