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2020

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Articles 8371 - 8400 of 10642

Full-Text Articles in Engineering

Carbon Emissions Reductions In Last Mile And Grocery Deliveries Utilizing Autonomous Vehicles, Miguel A. Figliozzi Jan 2020

Carbon Emissions Reductions In Last Mile And Grocery Deliveries Utilizing Autonomous Vehicles, Miguel A. Figliozzi

Civil and Environmental Engineering Faculty Publications and Presentations

New driverless air and ground vehicles are being launched and tested to deliver products or services in the areas of retail, groceries, and healthcare. This research focuses on the efficiency of autonomous (driverless) delivery vehicles in terms of vehicle-miles, energy consumption, and carbon emissions. Drones or UAVs, sidewalk autonomous delivery robots (SADRs), and road autonomous delivery robots (RADRs) vehicles carbon emissions are compared against emissions from an electric van (e-van), a conventional internal combustion engine van, and driving to a store utilizing electric and conventional vehicles. The impacts of vehicle capacity, range, and time constraints are analyzed as well as …

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Performance Evaluation Of A Carbon Nanotube Sensor For Fatigue Crack Monitoring Of Metal Structures, Shafique Ahmed, Thomas Schumacher, Erik T. Thostenson, Jennifer Mcconnell Jan 2020

Performance Evaluation Of A Carbon Nanotube Sensor For Fatigue Crack Monitoring Of Metal Structures, Shafique Ahmed, Thomas Schumacher, Erik T. Thostenson, Jennifer Mcconnell

Civil and Environmental Engineering Faculty Publications and Presentations

This article describes research that investigated the ability of a carbon nanotube (CNT) sensor to detect and monitor fatigue crack initiation and propagation in metal structures. The sensor consists of a nonwoven carrier fabric with a thin film of CNT that is bonded to the surface of a structure using an epoxy adhesive. The carrier fabric enables the sensor to be easily applied over large areas with complex geometries. Furthermore, the distributed nature of the sensor improves the probability of detecting crack initiation and enables monitoring of crack propagation over time. Piezoresistivity of the sensor enables strains to be monitored …

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Storm Tide Amplification And Habitat Changes Due To Urbanization Of A Lagoonal Estuary, Philip Orton, Eric W. Sanderson, Stefan Talke, Mario Giampieri, Kytt Macmanus Jan 2020

Storm Tide Amplification And Habitat Changes Due To Urbanization Of A Lagoonal Estuary, Philip Orton, Eric W. Sanderson, Stefan Talke, Mario Giampieri, Kytt Macmanus

Civil and Environmental Engineering Faculty Publications and Presentations

In recent centuries, human activities have greatly modified the geomorphology of coastal regions. However, studies of historical and possible future changes in coastal flood extremes typically ignore the influence of geomorphic change. Here, we quantify the influence of 20th-century man-made changes to Jamaica Bay, New York City, on present-day storm tides. We develop and validate a hydrodynamic model for the 1870s based on detailed maps of bathymetry, seabed characteristics, topography, and tide observations for use alongside a present-day model. Predominantly through dredging, landfill, and inlet stabilization, the average water depth of the bay increased from 1.7 to 4.5 m, tidal …

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Accessibility And Equity Analysis Of Common Carrier Parcel Lockers At Transit Facilities In Portland, Oregon, Katherine Keeling, Jaclyn S. Schaefer, Miguel Figliozzi Jan 2020

Accessibility And Equity Analysis Of Common Carrier Parcel Lockers At Transit Facilities In Portland, Oregon, Katherine Keeling, Jaclyn S. Schaefer, Miguel Figliozzi

Civil and Environmental Engineering Faculty Publications and Presentations

Transit goals have typically focused on commuter trips but facilitating urban last-mile freight logistics is a potential strategy to increase transit ridership and mitigate the demands of parcel distribution on the transportation network. Presently, most parcel lockers operate out of private businesses, but consumer surveys have found that transit users may be interested in locker facilities at transit connections. The implementation of an unmanned, secure, common carrier parcel locker system could have benefits for non-transit users as well. Consolidation of deliveries is expected to benefit courier companies by allowing operations at increasingly competitive rates, and retailers and consumers benefit from …

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An Empirical Study Of The Impacts Of Bicycles On Passenger Car Speeds On Urban Roads Without Bicycle Lanes, Jaclyn S. Schaefer, Miguel Figliozzi, Avinash Unnikrishnan Jan 2020

An Empirical Study Of The Impacts Of Bicycles On Passenger Car Speeds On Urban Roads Without Bicycle Lanes, Jaclyn S. Schaefer, Miguel Figliozzi, Avinash Unnikrishnan

Civil and Environmental Engineering Faculty Publications and Presentations

Higher bicycle mode share has been suggested as part of a solution to reduce the burden of congestion in urban areas. As strategies to promote bicycling are implemented, concerns have been raised by some road users and stakeholders citing simulation based traffic studies that indicate that an increase in the bicycle mode share generates major travel time delays via reduced vehicle speeds unless bicycle lanes are provided. The current research investigates the effects bicycles may have on motorized vehicle speeds on a variety of lower speed and volume urban roads without bicycle lanes. A detailed comparative analysis of passenger car …

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Smart Inverters For Distributed Pv Network Management, Colin Charles Levis Jan 2020

Smart Inverters For Distributed Pv Network Management, Colin Charles Levis

Theses

Securing a sustainable decarbonised economy involves moving towards a decentralised power system with increasing penetration levels of distributed photovoltaics (PVs) within the low voltage distribution network (LVDN). Increasing penetration levels of PV systems pose challenges for maintaining grid voltage and frequency stability. Thus requires studies and simulations to estimate the needs and technical requirements to overcome the challenges and maximise the opportunities. These simulations require time-domain system models with a high dynamic resolution such as electromagnetic transient (EMT) simulations with small-time steps that capture the required performance with large numbers of network elements. However, the small-time step implies a high …

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A Novel Calculation Method To Design Parasitic Decoupling Technique For Two Antennas, Min Li, Di Wu, Bing Xiao, Kwan Lawrence Yeung, Lijun Jiang Jan 2020

A Novel Calculation Method To Design Parasitic Decoupling Technique For Two Antennas, Min Li, Di Wu, Bing Xiao, Kwan Lawrence Yeung, Lijun Jiang

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, a systematic and calculation-based parasitic decoupling technique (PDT) is proposed to mitigate the mutual coupling between two closely coupled antennas. The adopted parasitic decoupling structure consists of two transmission lines connected to the feed lines of antennas and a parasitic element connected with a transmission line and terminated by a reactive load. Rigorous decoupling theory and systematic design procedures are presented. The lengths of transmission lines and value of reactive load can be precisely calculated to increase antenna isolation. The superiority of the proposed PDT is verified by four decoupling examples. The simulated and measured results show …

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Enhanced Pml Based On The Long Short Term Memory Network For The Fdtd Method, He Ming Yao, Lijun Jiang Jan 2020

Enhanced Pml Based On The Long Short Term Memory Network For The Fdtd Method, He Ming Yao, Lijun Jiang

Electrical and Computer Engineering Faculty Research & Creative Works

This paper proposes a new absorbing boundary condition (ABC) computation approach based on the deep learning technique. Benefited from the sequence dependence feature, the Long Short-Term Memory (LSTM) network is employed to replace the conventional perfectly matched layer (PML) ABC for the Finite-Difference Time-Domain (FDTD) solving process. The newly proposed LSTM based PML model is trained by the electromagnetic field data on the interface of the conventional PML. Different from the conventional PML, the newly proposed model only needs one cell layer as the boundary. Hence, the newly proposed method conveniently reduces both the algorithm's complexity and the area of …

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Numerical Methods For Electromagnetic Modeling Of Graphene: A Review, Kaikun Niu, Ping Li, Zhixiang Huang, Li (Lijun) Jun Jiang, Hakan Bagci Jan 2020

Numerical Methods For Electromagnetic Modeling Of Graphene: A Review, Kaikun Niu, Ping Li, Zhixiang Huang, Li (Lijun) Jun Jiang, Hakan Bagci

Electrical and Computer Engineering Faculty Research & Creative Works

Graphene's remarkable electrical, mechanical, thermal, and chemical properties have made this the frontier of many other 2-D materials a focus of significant research interest in the last decade. Many theoretical studies of the physical mechanisms behind these properties have been followed by those investing the graphene's practical use in various fields of engineering. Electromagnetics, optics, and photonics are among these fields, where potential benefits of graphene in improving the device/system performance have been studied. These studies are often carried out using simulation tools. To this end, many numerical methods have been developed to characterize electromagnetic field/wave interactions on graphene sheets …

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Electromagnetic-Circuital-Thermal Multiphysics Simulation Method: A Review, Huan Huan Zhang, Pan Pan Wang, Shuai Zhang, Long Li, Ping Li, Wei E.I. Sha, Li (Lijun) Jun Jiang Jan 2020

Electromagnetic-Circuital-Thermal Multiphysics Simulation Method: A Review, Huan Huan Zhang, Pan Pan Wang, Shuai Zhang, Long Li, Ping Li, Wei E.I. Sha, Li (Lijun) Jun Jiang

Electrical and Computer Engineering Faculty Research & Creative Works

Electromagnetic-circuital-thermal multiphysics simulation is a very important topic in the field of integrated circuits (ICs), microwave circuits, antennas, etc. This paper presents a comprehensive review of the state of the art of electromagnetic-circuital-thermal multiphysics simulation method. Most efforts were focused on electromagnetic-circuital co-simulation and electromagnetic-thermal cosimulation. A brief introduction of related theories like governing equations, numerical methods, and coupling mechanisms is also included.

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An Experimental Research On Cationic Reverse Flotation Of Anshan-Type Iron Ores, Zhonghang Chen, Dianbing Zhu, Shujuan Dai, Ahmed Sobhy Jan 2020

An Experimental Research On Cationic Reverse Flotation Of Anshan-Type Iron Ores, Zhonghang Chen, Dianbing Zhu, Shujuan Dai, Ahmed Sobhy

Mining Engineering Faculty Research & Creative Works

The mineral processing technology of Anshan-type iron ores has been developed in a rapid speed in recent years, and the combined flowsheet at the core of anionic reverse flotation has become a mainstream in the beneficiation of Anshan-type iron ores in China. With the successful application of this combined flowsheet, some obvious problems are also emerging. Such as high requirement of pulp temperature, complex reagent system, high cost of reagent consumption and so on. In view of this, we have carried out an experimental study on the separation of Anshan type iron ore by cationic reverse flotation. A new collector …

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Different Treatments Of Biochar Carbon Yp-50f To Enhance Specific Capacitance Of Supercapacitor, Ezaldeen Adhamash Jan 2020

Different Treatments Of Biochar Carbon Yp-50f To Enhance Specific Capacitance Of Supercapacitor, Ezaldeen Adhamash

Electronic Theses and Dissertations

High cost and environmentally unfavorable impacts are the significant difficulties that prohibit renewable energy storage from many applications. To work with these problems, novel renewable materials such as biomass derived carbon that have high surface area and low cost should be used. Renewable biochar carbon YP-50, synthesized from coconut, and activated using different plasma gases including methane (CH4), carbon dioxide (CO2), hydrogen (H2), and argon (Ar). Compared with the conventional activation method, the plasma treatment takes less effort and time. Significant improvements of the specific capacitance (SC) and specific surface area (SSA) were observed …

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Using Computational Fluid Dynamics To Accurately Model Agricultural Spray Nozzles, Zachary Chapman Jan 2020

Using Computational Fluid Dynamics To Accurately Model Agricultural Spray Nozzles, Zachary Chapman

Electronic Theses and Dissertations

Computational fluid dynamics (CFD) is a tool used by engineers in many industries to study fluid flow. A relatively new industry to adopt the use of CFD is the agricultural industry. The present work seeks to understand whether CFD can be used to accurately model spray nozzles. A spray nozzle commonly used in agricultural spraying was simulated. First, the impact of factors such as mesh size, mesh type, and physics models have on the solution were investigated. Next, a method to pulse the spray was determined. This was required to compare simulation results with experimental data. A user-defined function was …

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Semantic Segmentation Using Modified U-Net Architecture For Crack Detection, Michael Sun Jan 2020

Semantic Segmentation Using Modified U-Net Architecture For Crack Detection, Michael Sun

Electronic Theses and Dissertations

The visual inspection of a concrete crack is essential to maintaining its good condition during the service life of the bridge. The visual inspection has been done manually by inspectors, but unfortunately, the results are subjective. On the other hand, automated visual inspection approaches are faster and less subjective. Concrete crack is an important deficiency type that is assessed by inspectors. Recently, various Convolutional Neural Networks (CNNs) have become a prominent strategy to spot concrete cracks mechanically. The CNNs outperforms the traditional image processing approaches in accuracy for the high-level recognition task. Of them, U-Net, a CNN based semantic segmentation …

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Understanding The Effect Of Single- And Twin-Screw Extrusion Processing Parameters On Physical And Physico-Chemical Properties Of Sprouted Quinoa And Sprouted Proso Millets, Gabriela John Swamy Jan 2020

Understanding The Effect Of Single- And Twin-Screw Extrusion Processing Parameters On Physical And Physico-Chemical Properties Of Sprouted Quinoa And Sprouted Proso Millets, Gabriela John Swamy

Electronic Theses and Dissertations

According to Mordor Intelligence Research, the new compositional research and moisture content extrusion process are helping the growth of the plant protein market. The demand for plant proteins is growing at a fast rate, owing to change in lifestyle, lack of balanced dietary intake, and improved research and development in order to develop new kinds of plant-protein enriched products. It is necessary to identify the right plant protein sources and choose the right processing methodology to create highly digestible foods which can be consumed by infants and elderly as well. In addition, it is important to support local farmers and …

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A Series-Elastic Robot For Back-Pain Rehabilitation, Elhussein Shata Jan 2020

A Series-Elastic Robot For Back-Pain Rehabilitation, Elhussein Shata

Electronic Theses and Dissertations

Robotics research has been broadly expanding into various fields during the past decades. It is widely spread and best known for solving many technical necessities in different fields. With the rise of the industrial revolution, it upgraded many factories to use industrial robots to prevent the human operator from dangerous and hazardous tasks. The rapid development of application fields and their complexity have inspired researchers in the robotics community to find innovative solutions to meet the new desired requirements of the field. Currently, the creation of new needs outside the traditional industrial robots are demanding robots to attend to the …

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Effects Of Cellulose Nano-Fiber As An Additive On Performance Of Asphalt Binders And Mixes, Marco Paulo Pereira Castro Jan 2020

Effects Of Cellulose Nano-Fiber As An Additive On Performance Of Asphalt Binders And Mixes, Marco Paulo Pereira Castro

Electronic Theses and Dissertations

Findings of a study conducted on asphalt binders and mixes modified by addition of cellulose nanofiber (CNF) to evaluate the feasibility of them as an additive is presented in the current thesis. Cellulose Acetate (CA) is an ester of cellulose and is obtained by the reaction of cellulose with acetic anhydride and acetic acid in the presence of sulfuric acid. Due to its high temperature sensitivity, high ductility, large surface area, high strain resistance, and low electrical resistivity, cellulose acetate can be used for several application. The question is if CNF can be used as an additive in the asphalt, …

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Pig Pose Estimation Based On Extracted Data Of Mask R-Cnn With Vgg Neural Network For Classifications, Sang Kwan Lee Jan 2020

Pig Pose Estimation Based On Extracted Data Of Mask R-Cnn With Vgg Neural Network For Classifications, Sang Kwan Lee

Electronic Theses and Dissertations

This paper proposes a pig pose estimation operating with Region Proposal Network (RPN) of Mask Region based Convolutional Neural Network (Mask R-CNN) and Visual Geometry Group (VGG) Neural Network (NN). Object pose estimations generates from the associations of different key points. Key points could be explained as specific location of an object such as different joints of a human body or joints of different object. Hourglass network is one of a NN delivering key points of an object. Associating the different key points with the hourglass network results could be represented as instance-level detection [3]. However, the instance-level detection shows …

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Kernel-Controlled Dqn Based Cnn Pruning For Model Compression And Acceleration, Romancha Khatri Jan 2020

Kernel-Controlled Dqn Based Cnn Pruning For Model Compression And Acceleration, Romancha Khatri

Electronic Theses and Dissertations

Apart from the accuracy, the size of convolutional neural networks (CNN) models is another principal factor for facilitating the deployment of models on memory, power and budget constrained devices. However, conventional model compression techniques require human experts to setup parameters to explore the design space which is suboptimal and time consuming. Various pruning techniques are implemented to gain compression, trading off speed and accuracy. Given a CNN model [11], we propose an automated deep reinforcement learning [9] based model compression technique that can effectively turned off kernels on each layer by observing its significance on decision making. By observing accuracy, …

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Strain-Based Mechanical Failure Analysis Of Buried Steel Pipeline Subjected To Landslide Displacement Using Finite Element Method, Sean Goodluck Mamuzo Edeki Jan 2020

Strain-Based Mechanical Failure Analysis Of Buried Steel Pipeline Subjected To Landslide Displacement Using Finite Element Method, Sean Goodluck Mamuzo Edeki

Electronic Theses and Dissertations

Landslide displacement is one of the major threats to the structural integrity of buried oil and natural gas pipelines that are often located far from major markets with terrains prone to permanent ground deformations. These pipelines can experience large longitudinal strains and circumferential deformation resulting from the differential ground movements thereby potentially impacting pipeline safety by adversely affecting structural capacity and leak tight integrity. In order to proffer theoretical basis for the design, safety evaluation and maintenance of pipelines, the failure analysis and mechanical behavior of buried API X65 steel pipeline perpendicularly crossing landslide area was investigated with the Finite …

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Guest Editorial-Special Issue On Ground Control In Mining In 2019, Michael M. Murphy, Ted Klemetti, Heather Lawson, Brijes Mishra, Kyle A. Perry Jan 2020

Guest Editorial-Special Issue On Ground Control In Mining In 2019, Michael M. Murphy, Ted Klemetti, Heather Lawson, Brijes Mishra, Kyle A. Perry

Mining Engineering Faculty Research & Creative Works

No abstract provided.

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Enhanced Water Electrolysis: Effect Of Temperature On The Oxygen Evolution Reaction At Cobalt Oxide Nanoparticles Modified Glassy Carbon Electrodes, Aya Akl, Hany A. Elazab, Mohamed A. Sadek, Mohamed S. El-Deab Jan 2020

Enhanced Water Electrolysis: Effect Of Temperature On The Oxygen Evolution Reaction At Cobalt Oxide Nanoparticles Modified Glassy Carbon Electrodes, Aya Akl, Hany A. Elazab, Mohamed A. Sadek, Mohamed S. El-Deab

Chemical and Biochemical Engineering Faculty Research & Creative Works

Water splitting producing hydrogen and oxygen gases appears promising in view of the increasing need of renewable energy sources and storage strategies. Investigation of stable and highly efficient electrocatalysts for oxygen evolution reaction (OER) is targeted in this study at cobalt oxide nanoparticle modified glassy carbon (nano-CoOx/GC) electrodes. The effect of the preparation (Tp) and measuring temperature (Tm) on the electrocatalytic activity of nano-CoOx/GC towards the OER is investigated under various operating conditions. Linear sweep voltammetry (LSV), cyclic voltammetry (CV) as well as SEM and XRD techniques were used to probe the electrocatalytic and morphological characteristics of nano-CoOx prepared under …

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Synthesis And Characterization Of Pvp Based Catalysts For Selected Application In Catalysis, Hany A. Elazab, Mohamed N. Ayad, Mohamed M. Hammam, Mostafa A. Radwan, Mohamed A. Sadek Jan 2020

Synthesis And Characterization Of Pvp Based Catalysts For Selected Application In Catalysis, Hany A. Elazab, Mohamed N. Ayad, Mohamed M. Hammam, Mostafa A. Radwan, Mohamed A. Sadek

Chemical and Biochemical Engineering Faculty Research & Creative Works

This research aims to study the catalyst activity in specific reactions and the characteristics of the catalyst in order to optimize its performance. This research investigates PVP based catalysts and their properties and applications. PVP was prepared in combination with different metal oxides in order to be tested for different catalytic applications including dye removal. Methyl orange was used as a dye and different concentrations were tested against different metallic ions in order to optimize the catalyst for being used in dye removal applications. Spectrophotometer was used to calculate the concentration of the dye before and after catalyst exposure and …

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Impartial Sensor Tasking Via Forecasted Information Content Quantification, Matthew J. Gualdoni, Kyle J. Demars Jan 2020

Impartial Sensor Tasking Via Forecasted Information Content Quantification, Matthew J. Gualdoni, Kyle J. Demars

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The consistently increasing population of space debris in orbit about the Earth is becoming an increasingly unavoidable problem, necessitating a proper handling of the problem of sensor tasking to effectively and efficiently obtain observations of space objects to maintain catalogs of their positions and velocities. A variety of approaches have been explored to achieve this in an autonomous fashion, assisting with space traffic management. This work presents new statistical analysis of the Kullback–Leibler divergence justifying the use of its expected value in generating sensor schedules. This divergence's use as an objective measure is extended to simultaneously consider, in an impartial …

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Characterization Of Directed Energy Deposition Additively Manufactured Grcop-42 Alloy, Scott Landes Jan 2020

Characterization Of Directed Energy Deposition Additively Manufactured Grcop-42 Alloy, Scott Landes

Electronic Theses and Dissertations

GRCop is an alloy family constructed of copper, chromium, and niobium and was developed by NASA for high heat flux applications. The first of its kind, GRCop-84, was specifically designed for the environments seen by channel cooled main combustion chamber liners. To further increase thermal conductivity while maintaining material strength characteristics, the percentage of alloying elements were cut in half and GRCop- 42 was developed. In recent years, NASA has successfully additively manufactured GRCop with comparable material characteristics to wrought GRCop using a Laser Powder Bed Fusion (L-PBF) process. Benefits of this process include fabrication of intricate cooling channels as …

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Optimization Strategies For Myopic And Forecasted Divergence-Based Sensor Tasking Objectives, Matthew J. Gualdoni, Kyle J. Demars Jan 2020

Optimization Strategies For Myopic And Forecasted Divergence-Based Sensor Tasking Objectives, Matthew J. Gualdoni, Kyle J. Demars

Mechanical and Aerospace Engineering Faculty Research & Creative Works

In light of the ever-increasing value of space assets operating in the presence of a continuously growing population of space objects in orbit about Earth, space situational awareness is becoming more crucial than ever. The process of tracking and maintaining estimates for the numerous assets and space objects is a complex and highly demanding problem, as it requires robust state estimates in the presence of sparse data. As the number of space objects greatly outweighs the number of available sensors, a sensor tasking policy is necessary to properly utilize the available sensor resources in a way that ensures targets are …

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Impact Of Considering And Neglecting States On Descent-To-Landing Navigation, Kyle J. Demars, Kari C. Ward Jan 2020

Impact Of Considering And Neglecting States On Descent-To-Landing Navigation, Kyle J. Demars, Kari C. Ward

Mechanical and Aerospace Engineering Faculty Research & Creative Works

This paper develops a novel square-root formulation of the consider/neglect Kalman filter for navigation applications. The proposed filter partitions system parameters into three distinct categories: those to be estimated by the filter, those whose contribution to the system can be considered without explicitly estimating them, and those with sufficiently low effect on the system such that their contribution can be neglected altogether. Discussion on appropriate selection of consider and neglect parameters is provided with specific attention given to descent-to-landing navigation. Monte Carlo simulations and analysis are performed to assess the performance of the square-root consider/neglect filter.

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Robustness Metric For Robust Design Optimization Under Time-And Space-Dependent Uncertainty Through Metamodeling, Xinpeng Wei, Xiaoping Du Jan 2020

Robustness Metric For Robust Design Optimization Under Time-And Space-Dependent Uncertainty Through Metamodeling, Xinpeng Wei, Xiaoping Du

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Product performance varies with respect to time and space in many engineering applications. This paper discusses how to measure and evaluate the robustness of a product or component when its quality characteristics (QCs) are functions of random variables, random fields, temporal variables, and spatial variables. At first, the existing time-dependent robustness metric is extended to the present time-and space-dependent problem. The robustness metric is derived using the extreme value of the quality characteristics with respect to temporal and spatial variables for the nominal-the-better type quality characteristics. Then, a metamodel-based numerical procedure is developed to evaluate the new robustness metric. The …

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Design And Analysis Of Descent-To-Landing Navigation Incorporating Terrain Effects, Kari C. Ward, Gunner S. Fritsch, J. Cameron Helmuth, Kyle J. Demars, James S. Mccabe Jan 2020

Design And Analysis Of Descent-To-Landing Navigation Incorporating Terrain Effects, Kari C. Ward, Gunner S. Fritsch, J. Cameron Helmuth, Kyle J. Demars, James S. Mccabe

Mechanical and Aerospace Engineering Faculty Research & Creative Works

This study investigated the ability of a navigation filter to process multiple terrain-based sensors, such as slant-range, slant-speed, and terrain relative navigation sensors, during a descent-to-landing scenario to estimate the state of a landing vehicle. The filtering technique leveraged was based upon a factorized form of the multiplicative extended Kalman filter, and terrain-based measurements were fused with star camera and inertial measurement unit sensor returns to estimate the position, velocity, and attitude of the landing vehicle. Monte Carlo simulations were carried out to assess the performance of the navigation filter along a lunar descent trajectory, as well as the consistency …

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Effect Of Subsurface Microseismicity On The Motion Of Surrounding Dispersed Droplets: Supporting Information, Chao Zeng, Wen Deng Jan 2020

Effect Of Subsurface Microseismicity On The Motion Of Surrounding Dispersed Droplets: Supporting Information, Chao Zeng, Wen Deng

Research Data

The human-induced seismicity has called substantial attention in recent years. The effect of seismicity on the subsurface structure has been extensively studied. However, the effect of seismicity, especially those microseismicity, on surrounding immiscible fluids is rarely investigated. In porous media with two or more immiscible fluids, different amplitudes of vibration induced by seismicity have distinct effects on the dynamic behavior of fluids. Three types of pore-scale models are prevalent in the analysis of the motion of immiscible droplets. The underlying assumptions and accuracy of these models are compared in this study in both frequency domain and time domain. The frequency …

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