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Articles 751 - 780 of 10505
Full-Text Articles in Engineering
Handwriting Character Recognition Usingvector Quantization Technique, Haviluddin Haviluddin, Rayner Alfred, Ni’Mah Moham, Herman Santoso Pakpahan, Islamiyah Islamiyah, Hario Jati Setyadi
Handwriting Character Recognition Usingvector Quantization Technique, Haviluddin Haviluddin, Rayner Alfred, Ni’Mah Moham, Herman Santoso Pakpahan, Islamiyah Islamiyah, Hario Jati Setyadi
Knowledge Engineering and Data Science
This paper seeks to explore Learning Vector Quantization (LVQ) processing stage to recognize The Buginese Lontara script from Makassar as well as explaining its accuracy. The testing results of LVQ obtained an accuracy degree of 66.66 %. The most optimal variant of network architecture in the recognition process is a variation of learning rate of 0.02, a maximum epoch of 5000 and a hidden layer of 90 neurons which was the result of recognition based on feature 8. Based on these variations, the obtained performance with a mean square error (MSE) of 0.0306 and the time required during the learning …
The Effectiveness Of Augmented Reality For Astronauts On Lunar Missions: An Analog Study, Godfrey Valencio D’Souza
The Effectiveness Of Augmented Reality For Astronauts On Lunar Missions: An Analog Study, Godfrey Valencio D’Souza
Doctoral Dissertations and Master's Theses
The uses of augmented reality and head-up displays are becoming more prominent in industries such as aviation, automotive, and medicine. An augmented reality device such as the Microsoft HoloLens can project holograms onto the user’s natural field of view to assist with completion of a variety of tasks. Unfortunately, only a little research and development has begun in the space sector for astronauts using these head-up displays. Future lunar missions could incorporate augmented reality for astronauts to ease task load and improve accuracy. This study evaluated the usability, subjective workload, and task performance of 22 participants using the Microsoft HoloLens …
Development Of A Research Spacecraft Test-Bed With Implementation Of Control Laws To Compensate Undesired Dynamics, Yomary Angélica Betancur Vesga
Development Of A Research Spacecraft Test-Bed With Implementation Of Control Laws To Compensate Undesired Dynamics, Yomary Angélica Betancur Vesga
Doctoral Dissertations and Master's Theses
The development of research spacecraft systems has a significant impact on the preparation and simulation of future space missions. Hardware, software and operation procedures can be adequately tested, validated and verified before they are deployed for the actual mission. In this thesis, a spacecraft vehicle test-bed named Extreme Access System (EASY) was developed. EASY aims at supporting validation and verification of guidance, navigation and control algorithms. Description of EASY spacecraft systems, sub-systems and integration is presented in this thesis along with an analysis of results from numerical simulation and actual implementation of control laws. An attitude control architecture based on …
Fuel Efficient Control Design And Constrained Motion Analysis For Spacecraft Coulomb Formation In Elliptic Chief Orbits, Muhammad Wasif Memon
Fuel Efficient Control Design And Constrained Motion Analysis For Spacecraft Coulomb Formation In Elliptic Chief Orbits, Muhammad Wasif Memon
Doctoral Dissertations and Master's Theses
The use of Coulomb force has been analyzed in recent years to provide propulsion in space for various applications. Coulomb formation can also be utilized to make close formation spacecraft missions fuel efficient. In this study, the Coulomb formation of two craft is studied in elliptic chief orbits for two formation geometries. The first formation requires both spacecraft to be aligned along the nadir (radial) direction and the second formation requires both spacecraft to maintain a constant separation distance relative to each other while each spacecraft rotates freely on the surface of a sphere with the ratio of the radii …
Numerical Investigation Of Scaling Effects Of A Ramjet-Powered Projectile, Arjun Jaishankar Vedam
Numerical Investigation Of Scaling Effects Of A Ramjet-Powered Projectile, Arjun Jaishankar Vedam
Doctoral Dissertations and Master's Theses
Ramjet flowpath miniaturization is a potentially useful technology for integration into munitions to increase range, accuracy, and lethality. The emphasis of this effort is to numerically characterize the performance of a miniature hydrogen-fueled and ethylene-fueled ramjet flowpath during Mach 3 and Mach 3.5 sea-level flight. The effect of geometric scale on ramjet performance is evaluated using high-fidelity RANS CFD models. Sensitivity to nonequilibrium laminar and turbulence-limited chemistry, and transitional turbulence treatments are evaluated. The physical sources of small scale performance limitations are identified for both fuel types. Finally, flowpath integration for small-scale applications is briefly addressed.
In-Situ Measurement Of Resin Shrinkage For Aerospace Components, Samarth Motagi
In-Situ Measurement Of Resin Shrinkage For Aerospace Components, Samarth Motagi
Doctoral Dissertations and Master's Theses
Resin shrinkage due to chemical changes and thermal gradients plays an important role in the residual stress evolution during composite manufacturing. In this thesis, we develop a new in-situ experimental approach for measuring resin shrinkage during curing with the help of digital image correlation (DIC) instrumented on a specially designed autoclave with borosilicate viewports. The images of the resin sample are captured at regular intervals with the help of DIC to measure the displacement and strains during the curing process. We utilize this method for a comparative analysis of resin shrinkage in two common aerospace epoxies, Epoxy 105 and EPON …
Adaptive Learning Terrain Estimation For Unmanned Aerial Vehicle Applications, Pedro L. Vergara Garcia
Adaptive Learning Terrain Estimation For Unmanned Aerial Vehicle Applications, Pedro L. Vergara Garcia
Doctoral Dissertations and Master's Theses
For the past decade, terrain mapping research has focused on ground robots using occupancy grids and tree-like data structures, like Octomap and Quadtrees. Since flight vehicles have different constraints, ground-based terrain mapping research may not be directly applicable to the aerospace industry. To address this issue, Adaptive Learning Terrain Estimation algorithms have been developed with an aim towards aerospace applications. This thesis develops and tests Adaptive Learning Terrain Estimation algorithms using a custom test benchmark on representative aerospace cases: autonomous UAV landing and UAV flight through 3D urban environments. The fundamental objective of this thesis is to investigate the use …
Computational Model For Pedestrian Movement And Infectious Diseases Spread During Air Travel: A Molecular Dynamics-Like Numerical Approach, Pierrot Derjany
Computational Model For Pedestrian Movement And Infectious Diseases Spread During Air Travel: A Molecular Dynamics-Like Numerical Approach, Pierrot Derjany
Doctoral Dissertations and Master's Theses
There is direct evidence of the transmission of fatal infectious pathogens in large human gatherings. Air transportation is no exception. The mixing of susceptible and infectious individuals in this high-density man-made environment involves pedestrian movement which is generally not taken into account in modeling studies of disease dynamics. This thesis addresses this problem through a multiscale model that combines pedestrian dynamics with stochastic infection spread models. This generic model is applicable to several directly transmitted diseases. Through this multiscale framework, the effectiveness of certain layout and strategies in suppressing the disease spread in highly crowded locations such as airplanes, airports …
A Step Toward Ending Long Airport Security Lines: The Modified Boarding Pass, Joel Lee
A Step Toward Ending Long Airport Security Lines: The Modified Boarding Pass, Joel Lee
Doctoral Dissertations and Master's Theses
Anyone who has traveled by air has most likely experienced long airport security lines. Yet not much is known about its cause because few have considered if passengers have created this problem for themselves. The present study attempts to fill this research gap by suggesting that when passengers are not well-prepared for security screening, they delay the process by making mistakes and not complying with procedures. This lack of preparedness can be attributed to several shortcomings of security signposts. This study proposes the use of a modified boarding pass as an alternative form of signage to help passengers better prepare …
Astrodynamics Of The Next Generation Space Weather Prediction Mission, Mark Herring
Astrodynamics Of The Next Generation Space Weather Prediction Mission, Mark Herring
Doctoral Dissertations and Master's Theses
Accurate prediction of the solar wind properties, interplanetary magnetic field direction and various space weather phenomena becomes ever more important as our dependence on Earth orbiting spacecraft increases. Different solar wind drivers can lead both to enhancements and losses of relativistic electrons in the outer radiation belts, thus posing a major risk to satellites. To further our understanding of the Sun’s impact on the near Earth space environment, as well as to provide predictive capabilities, a mission placing monitoring satellites in key orbits in the inner Solar System is being proposed. As part of that effort, the possibility of using …
Autonomous Autorotation Of A Tilt-Rotor Aircraft Using Model Predictive Control, Elias Wilson
Autonomous Autorotation Of A Tilt-Rotor Aircraft Using Model Predictive Control, Elias Wilson
Doctoral Dissertations and Master's Theses
Tilt rotor vehicles are governed by FAA laws also used for conventional helicopters, which require autorotational maneuvering and landing given a total power failure. With low inertia rotors and high disk loading of tilt rotor vehicles, this already difficult task becomes significantly more challenging. In this work, a model predictive controller is developed to autonomously maneuver and land a tilt rotor given complete power loss. A high fidelity model of a tilt rotor vehicle is created and used to simulate the vehicle dynamics and response to control inputs. A reduced order dynamic model is used within a model predictive control …
Comparison Of Indonesian Imports Forecastingby Limited Period Using Sarima Method, Harits Ar Rosyid, Mutyara Whening Aniendya, Heru Wahyu Herwanto
Comparison Of Indonesian Imports Forecastingby Limited Period Using Sarima Method, Harits Ar Rosyid, Mutyara Whening Aniendya, Heru Wahyu Herwanto
Knowledge Engineering and Data Science
The development of Indonesia's imports fluctuate over years. Inability to anticipate such rapid changes can cause economic slump due to inappropriate policy. For instance, recent years imports in rice led to the extermination of rice reserves. The reason is to maintain the market price of rice in Indonesia. To overcome these changes, forecasting the amount of imports should assist the Government in determining the optimum policy. This can be done by utilizing an algorithm to forecast time series data, in this case the amount of imports in the next few months with a high degree of accuracy. This study uses …
Mandela Splash Pad Pre-Construction Plan, Levi Sandbulte
Mandela Splash Pad Pre-Construction Plan, Levi Sandbulte
Theses/Capstones/Creative Projects
In the construction industry, it is the responsibility of the general contractor to take the architect’s ideas and turn it into a real building. Many times this requires ample communication and several drafts. This efficient execution of this process is vital to the completion of a successful project. In this project, I practice this communication process. The challenge presented by the owner is to build an affordable splash pad, and without impacting the construction schedule of the Early Childhood Development Center (ECDC) that is being built on the same property at the same time. This proposal gives the owner a …
Waste Gasification, Glyn D. Lewis, Nash Taylor, Nicholas L. Ordonez, David S. Mccallum
Waste Gasification, Glyn D. Lewis, Nash Taylor, Nicholas L. Ordonez, David S. Mccallum
Mechanical Engineering
This document summarizes the work the IGT Team has conducted on the topic of waste to energy gasification over the Cal Poly Winter, Spring, and Fall quarters of 2019. The project is being carried out by four Cal Poly Mechanical Engineering students: Nash Taylor, Glyn Lewis, David McCallum, and Nicholas Ordonez and the sponsor of this project is Tod duBois. The team’s original goal was to successfully create a system that compiles residential solid waste on a small scale, gasifies it, and measures the typical syngas outputs, so that the team may assess the viability of gasification of household waste …
Deployable Cover For Cubesat Fuv Imager, Edwin J. Rainville, Patrick J. Rainville, Jeff Wagner
Deployable Cover For Cubesat Fuv Imager, Edwin J. Rainville, Patrick J. Rainville, Jeff Wagner
Mechanical Engineering
The goal is to develop a deployable cover for a far ultraviolet imager cube satellite that will be used to map the earth’s auroras in the ionosphere. The deployable cover is used to protect the Far Ultra-Violet (FUV) sensor and lenses, house two mirrors which are used to filter unwanted light and expose optics when deployed. The deployable cover consists of a door, an actuator, a lockout mechanism, and an “open position” indicator. This project also includes designing a fixture for testing the optical alignment of the deployable cover after launch and during orbital conditions. The subassembly is required to …
Model Block Press Design, Ben Todd Van Hamersveld, Chester Wong, Alexander Wing-Jon Giannousis
Model Block Press Design, Ben Todd Van Hamersveld, Chester Wong, Alexander Wing-Jon Giannousis
Mechanical Engineering
This project’s goal is to redesign the Center for Vocational Building Technology (CVBT) BP9 earth block press, which makes 1/3 scale compressed earth blocks to build demonstration model homes in Thailand. The full-scale block press, the BP6, provides a sustainable and affordable technique for constructing habitable homes in Thailand. The BP9 serves as a tool to inform the public of the advantages of human-powered earth block presses through demonstration. The BP9 press design has multiple problems: it is too expensive to manufacture, there is too much friction when used, it has several weak points due to users unintentionally applying excessive …
Tumble Bot, Alena Beyer, Blake Gonzales, Jensen Severance, Liam Chaffey
Tumble Bot, Alena Beyer, Blake Gonzales, Jensen Severance, Liam Chaffey
Mechanical Engineering
Passive locomotion is the ability for an object to move from one place to another by the means of the environment. In nature species such as tumbleweed, fox tails, plankton, and man o’ war jellyfish rely on passive modes of transportation for survival and are able to cross vast distances with little to no expenditure of their own energy. This document seeks to explore the feasibility of building a machine relies on the energy of Mars’ environment to explore the Martian surface.
The “Tensegrity Tumbleweed Locomotion” (nicknamed Tumble Bot) senior project was sponsored by NASA Jet Propulsion Laboratory (JPL). The …
Mad Jack Alpine Touring Model Design, Austin Gasbarra, Gillian Stargensky, Madeleine Mccool, Brannon Smudz
Mad Jack Alpine Touring Model Design, Austin Gasbarra, Gillian Stargensky, Madeleine Mccool, Brannon Smudz
Mechanical Engineering
Skiing is a sport enjoyed by millions of people every year, yet ski boots are very uncomfortable and cost- prohibitive, resulting in a low conversion rate of first-time skiers to lifetime skiers. Additionally, Alpine Touring (AT) is seeing a surge in popularity as ski resorts become more expensive, but few companies are developing affordable products in this realm. Mad Jack Snow Sports has developed a product that they believe addresses some of the main issues associated with skiing, but they want to develop their product line further. The problem statement and scope state that the purpose of this project is …
Critical Radius Of Insulation, Maria N. Ambrose, Samuel J. Sayre, Travis W. Martin, Matt T. Sterling
Critical Radius Of Insulation, Maria N. Ambrose, Samuel J. Sayre, Travis W. Martin, Matt T. Sterling
Mechanical Engineering
The critical radius of insulation is a counterintuitive concept within the study of heat transfer. The theory states that adding insulation to a cylindrical or spherical object will increase the rate of heat loss rather than decrease it, if the radius (thickness) of the insulation is at its “critical” value. The Critical Radius of Insulation Senior Project is designed to demonstrate this phenomenon to Heat Transfer students via a portable apparatus. The concept will be demonstrated with a cylindrical object which is heated by way of a separate voltage source. Thermocouples will display the temperature of the cylinder while insulation …
Resource Allocation And Task Scheduling Optimization In Cloud-Based Content Delivery Networks With Edge Computing, Yang Peng
Operations Research and Engineering Management Theses and Dissertations
The extensive growth in adoption of mobile devices pushes global Internet protocol (IP) traffic to grow and content delivery network (CDN) will carry 72 percent of total Internet traffic by 2022, up from 56 percent in 2017. In this praxis, Interconnected Cache Edge (ICE) based on different public cloud infrastructures with multiple edge computing sites is considered to help CDN service providers (SPs) to maximize their operational profit. The problem of resource allocation and performance optimization is studied in order to maximize the cache hit ratio with available CDN capacity.
The considered problem is formulated as a multi-stage stochastic linear …
Evaluation Of Fire-Affected Concrete Structures By Non-Destructive Testing Methods, Upal Mohammad Towfiqul Quadir
Evaluation Of Fire-Affected Concrete Structures By Non-Destructive Testing Methods, Upal Mohammad Towfiqul Quadir
Civil Engineering Dissertations - Archive
Fire hazard on concrete structures has been a significant concern around the world. After a fire hazard, the crucial part is the evaluation of the fire-affected concrete for strengthening or demolition. For evaluation of a fire-affected concrete structure, Non-destructive Testing (NDT) methods would certainly be a more viable option than the destructive testing methods. Until now, no specific code was developed for quantifiable evaluation of fire-affected concrete with NDT. To develop the method for Non-destructive Evaluation (NDE) of fire-affected concrete, 8 small-sized (4 in x 4 in x 15 in) and 32 medium-sized (8 in x 8 in x 36 …
Development Of A Machine Learning-Based Prediction Model For Construction And Environmental Costs Of Trenchless Spray-Applied Pipe Linings, Cured-In-Place Pipe, And Sliplining Methods In Large Diameter Culverts, Ramtin Serajiantehrani
Development Of A Machine Learning-Based Prediction Model For Construction And Environmental Costs Of Trenchless Spray-Applied Pipe Linings, Cured-In-Place Pipe, And Sliplining Methods In Large Diameter Culverts, Ramtin Serajiantehrani
Civil Engineering Dissertations - Archive
According to U.S. Department of Transportation, Federal Highway Administration there are more than 4.1 million miles of road in total length, making it the world’s longest and biggest road network with millions of culverts hidden underneath the road in the United States. The development of underground infrastructure, concerns about environmental impacts, and economic trends are influencing society, resulting in the advancement of technology for more environment-friendly and cost-effective pipeline rehabilitation. Trenchless technologies employ innovative methods, materials, and equipment that require minimum surface excavation and access area for rehabilitation of old and deteriorated culverts. Trenchless technologies can be used when other …
Silver-Based Microbial Check Valve For Spacecraft Potable Water Systems, Tanner Burns
Silver-Based Microbial Check Valve For Spacecraft Potable Water Systems, Tanner Burns
Chemical Engineering Undergraduate Honors Theses
As human space exploration increases, the development of a more efficient potable water treatment system suited for spacecraft becomes crucial. This Waste-management Education Research Consortium (WERC) challenge was designed to explore the viability of microbial control through the utilization of silver ions as a biocide for possible integration into the Tranquility Node 3 water purification system aboard the International Space Station (ISS). Current systems using iodine risk causing hyperthyroidism from overexposure; however, silver can be safely ingested without this side effect. After researching silver delivery methods including electrochemical ion production, controlled release, or a combination of the two, our team …
Evaluation Of Reducing Cement Content In Ndor Class R Combined Aggregate Gradations, Miras Mamirov, Jiong Hu, Yong-Rak Kim
Evaluation Of Reducing Cement Content In Ndor Class R Combined Aggregate Gradations, Miras Mamirov, Jiong Hu, Yong-Rak Kim
Nebraska Department of Transportation: Research Reports
The main objective of this research project was to achieve a cement reduction on Nebraska slip-form pavement concrete through aggregate particle packing optimization. A literature review was conducted to examine different aggregate optimization tools, quality control tests, and historical data of Nebraska Department of Transportation (NDOT) pavement mixtures. It was found that the Modified Toufar Model has good potential in optimizing particle packing and predicting packing degrees. The combined aggregate void content test was found to be useful to experimentally justify optimized aggregate gradations. The Box Test with a modified index and image analysis tool for surface void estimation was …
Long-Term Performance Evaluation Of Nudeck In Kearney East Bypass, George Morcous, Marc Maguire
Long-Term Performance Evaluation Of Nudeck In Kearney East Bypass, George Morcous, Marc Maguire
Nebraska Department of Transportation: Research Reports
The Kearney East Bypass bridge is the first project that implements the newly developed precast concrete deck system (known as 2nd generation NUDECK). The new system consists of full-depth full-width precast prestressed concrete deck panels that are 12 ft (3.66 m) long each. The panels have covered shear pockets at 4 ft (1.22 m) spacing on each girder line to host clustered shear connectors that are adjustable in height. Narrow unreinforced transverse joints are used to eliminate the need for deck overlay. Also, deck panels are post-tensioned in the longitudinal direction using a new post-tensioning system that eliminates the need …
Standard Design For Nebraska County Bridges, Chungwook Sim, Jiong Hu, Maher K. Tadros, Alexander Bleyhl, David Gee
Standard Design For Nebraska County Bridges, Chungwook Sim, Jiong Hu, Maher K. Tadros, Alexander Bleyhl, David Gee
Nebraska Department of Transportation: Research Reports
Many county-owned bridges in Nebraska need replacement due to their structural deficiency. Most of the bridges needing replacement are in the 40 to 60 ft range. This span range lacks a standard design that fits Nebraska county practices in terms of speed and simplicity of construction. The current systems being used are (a) Precast 1 by 2 ft planks which can span up to 30 ft, (b) Cast-in-place slab bridges which can span up to 50 ft but require extensive field formwork, concrete placing, and curing, and are best when constructed in three-span units, and (c) Inverted tees which can …
Precast Concrete Deck-To-Girder Connection Using Uhpc, George Morcous, Mostafa Abo El-Khier
Precast Concrete Deck-To-Girder Connection Using Uhpc, George Morcous, Mostafa Abo El-Khier
Nebraska Department of Transportation: Research Reports
The implementation of ultra-high-performance concrete (UHPC) in bridge construction has been growing rapidly in the last two decades due to its excellent mechanical properties, workability, and durability. This report presents a new UHPC connection between precast concrete deck panels and bridge girders that eliminates changes to the design and production of girder shear connectors commonly used in conventional cast-in-place concrete deck construction. In conventional construction, girder shear reinforcement or studs are extended into the cast-in-place concrete deck to transfer interface shear and create composite section. In the new connection, girder shear reinforcement or studs are kept underneath the deck panels, …
Development Of High-Performance Rapid Patching Materials For Pavement Repair, Gholami Shayan, Jiong Hu, Yong-Rak Kim
Development Of High-Performance Rapid Patching Materials For Pavement Repair, Gholami Shayan, Jiong Hu, Yong-Rak Kim
Nebraska Department of Transportation: Research Reports
Concrete pavements exhibiting severe distresses which require patching are commonly observed in the concrete pavement in Nebraska. Due to the requirements of opening pavement to traffic after placing the rapid patching materials, it is essential for that concrete to achieve high early strength. To ensure this, a high cement content and chloride-based accelerators are currently used in the Nebraska Department of Transportation (NDOT) Portland cement-based rapid-patching materials. Besides its associated high cost, high cement content tends to result in a less stable mix with high shrinkage, high heat of hydration, and high cracking potential. In addition, using chloride-based accelerators has …
Condition Assessment Of Bridge Decks With Asphalt Overlay, Sepehr Pashoutani, Jinying Zhu
Condition Assessment Of Bridge Decks With Asphalt Overlay, Sepehr Pashoutani, Jinying Zhu
Nebraska Department of Transportation: Research Reports
Ground penetrating RADAR (GPR) is a widely used nondestructive testing (NDT) method for bridge deck evaluation. However, the current GPR signal and data processing software and algorithms are not able to provide comprehensive information about bridge deck condition. Although the original objective of this research project was to develop GPR analysis algorithms for condition assessment of bridge decks with asphalt overlay, the scope of work has been expanded to concrete bridge decks with or without overlays.
In this study, the research team developed a complete GPR analysis procedure that includes the following components: 1) obtain zero-time for GPR reflection at …
High Frequency Ltcc Based Planar Transformer, Adithya Venkatanarayanan
High Frequency Ltcc Based Planar Transformer, Adithya Venkatanarayanan
Graduate Theses and Dissertations
As we move towards high power and higher frequency related technology, conventional wire-wound magnetics have their own limitations which has led path to the development of planar based magnetic materials. Nowadays more planar magnetic technology has been employed because it is easier to fabricate them. The planar magnetic is a transformer or an inductor that replaces the wire-wound transformer or inductors which generally uses copper wires. One of the main reasons why we move to planar magnetic technology is its operation at higher frequency which provides higher power density. This study explains in detail about the design and fabrication of …