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Full-Text Articles in Engineering

Can Neuromorphic Computer Vision Inform Vision Science? Disparity Estimation As A Case Study, Guido Maiello, Manuela Chessa, Peter J. Bex, Fabio Solari May 2016

Can Neuromorphic Computer Vision Inform Vision Science? Disparity Estimation As A Case Study, Guido Maiello, Manuela Chessa, Peter J. Bex, Fabio Solari

MODVIS Workshop

The primate visual system efficiently and effectively solves a multitude of tasks from orientation detection to motion detection. The Computer Vision community is therefore beginning to implement algorithms that mimic the processing hierarchies present in the primate visual system in the hope of achieving flexible and robust artificial vision systems. Here, we reappropriate the neuroscience “borrowed” by the Computer Vision community and ask whether neuromorphic computer vision solutions may give us insight into the functioning of the primate visual system. Specifically, we implement a neuromorphic algorithm for disparity estimation and compare its performance against that of human observers. The algorithm …


3-D Shape Recovery From A Single Camera Image, Vijai Jayadevan, Aaron Michaux, Edward Delp, Zygmunt Pizlo May 2016

3-D Shape Recovery From A Single Camera Image, Vijai Jayadevan, Aaron Michaux, Edward Delp, Zygmunt Pizlo

MODVIS Workshop

3-D shape recovery is an ill-posed inverse problem which must be solved by using a priori constraints. We use symmetry and planarity constraints to recover 3-D shapes from a single image. Once we assume that the object to be reconstructed is symmetric, all that is left to do is to estimate the plane of symmetry and establish the symmetry correspondence between the various parts of the object. The edge map of the image of an object serves as a good representation of its 2-D shape and establishing symmetry correspondence means identifying pairs of symmetric curves in the edge map. The …


Figure-Ground Organization Using 3d Symmetry, Aaron Michaux, Vijai Jayadevan, Edward Delp, Zygmunt Pizlo May 2016

Figure-Ground Organization Using 3d Symmetry, Aaron Michaux, Vijai Jayadevan, Edward Delp, Zygmunt Pizlo

MODVIS Workshop

We present a novel approach to object localization using mirror symmetry as a general purpose and biologically motivated prior. 3D symmetry leads to good segmentation because (i) almost all objects exhibit symmetry, and (ii) configurations of objects are not likely to be symmetric unless they share some additional relationship. Furthermore, psychophysical evidence suggests that the human vision system makes use symmetry in constructing 3D percepts, indicating that symmetry may be important in object localization. No general purpose approach is known for solving 3D symmetry correspondence in 2D camera images, because few invariants exist. Therefore, to test symmetry as a clustering …


An Image-Based Model For Early Visual Processing, Heiko H. Schütt, Felix A. Wichmann May 2016

An Image-Based Model For Early Visual Processing, Heiko H. Schütt, Felix A. Wichmann

MODVIS Workshop

No abstract provided.


Modelling Short-Latency Disparity-Vergence Eye Movements Under Dichoptic Unbalanced Stimulation, Agostino Gibaldi, Guido Maiello, Peter J. Bex, Silvio P. Sabatini May 2016

Modelling Short-Latency Disparity-Vergence Eye Movements Under Dichoptic Unbalanced Stimulation, Agostino Gibaldi, Guido Maiello, Peter J. Bex, Silvio P. Sabatini

MODVIS Workshop

Vergence eye movements align the optical axes of our two eyes onto an object of interest, thus facilitating the binocular summation of the images projected onto the left and the right retinae into a single percept. Both the computational substrate and the functional behaviour of binocular vergence eye movements have been the topic of in depth investigation. Here, we attempt to bring together what is known about computation and function of vergence mechanism. To this aim, we evaluated of a biologically inspired model of horizontal and vertical vergence control, based on a network of V1 simple and complex cells. The …


Measuring And Modeling Shared Visual Attention, Jeffrey B. Mulligan, Patrick Gontar May 2016

Measuring And Modeling Shared Visual Attention, Jeffrey B. Mulligan, Patrick Gontar

MODVIS Workshop

Multi-person teams are sometimes responsible for critical tasks, such as flying an airliner. Here we present a method using gaze tracking data to assess shared visual attention, a term we use to describe the situation where team members are attending to a common set of elements in the environment. Gaze data are quantized with respect to a set of N areas of interest (AOIs); these are then used to construct a time series of N dimensional vectors, with each vector component representing one of the AOIs, all set to 0 except for the component corresponding to the currently fixated …


Energy Transfer And Localization In Molecular Crystals, Mitchell A. Wood May 2016

Energy Transfer And Localization In Molecular Crystals, Mitchell A. Wood

Open Access Dissertations

With the aim of developing new technologies for the detection and defeat of energetic materials, this collection of work was focused on using simulations to characterize materials at extremes of temperature, pressure and radiation. Each branch of the work here is collected by which material response is potentially used as the detectable signal.

Where the chemical response is of interest, this work will explore the possibility of non-statistical chemical reactions in condensed-phase energetic materials via reactive molecular dynamics (MD) simulations. We characterize the response of three unique high energy density molecular crystals to different means of energy input: electric fields …


Numerical And Analytical Modeling To Determine Performance Trade-Offs In Hydrogel-Based Ph Sensors, Piyush Dak, Muhammad Ashraful Alam May 2016

Numerical And Analytical Modeling To Determine Performance Trade-Offs In Hydrogel-Based Ph Sensors, Piyush Dak, Muhammad Ashraful Alam

Birck and NCN Publications

Hydrogel based pH sensors are promising candidates for implantable sensors due to their low-cost and biocompatibility. Despite their commercial potential and numerous theoretical/experimental reports, the trade-offs between different performance parameters are not well understood, and explicitly stated. In this work, we develop a numerical and analytical framework to show that there is a fundamental trade-off between the performance parameters i.e. sensitivity/dynamic range vs. response-time/response-asymmetry in hydrogel sensors under constrained swelling conditions. Specifically, we consider the effect of the gel parameters, such as the ionizable group density ( Nf) and its dissociation constant ( Ka), on the …


Simulation Of Conservation Practice Effects On Water Quality Under Current And Future Climate Scenarios, Carlington W. Wallace May 2016

Simulation Of Conservation Practice Effects On Water Quality Under Current And Future Climate Scenarios, Carlington W. Wallace

Open Access Dissertations

Analysis of the effects of implementing different conservation practices, as well as increased levels of conservation practices under existing and projected future climate, will determine if current conservation practice recommendations will be sufficient to maintain soil and water resources. The Soil and Water Assessment Tool (SWAT) was used to study four watersheds of different sizes (CCW = 680 km2, F34 = 183 km2, AXL = 42 km 2 and ALG = 20 km2) located in Northeastern Indiana. The overarching goal of this study was to evaluate the effect of various agricultural practices on runoff and agricultural chemical losses under current …


Markov-Based Ranking Methods, Baback Vaziri May 2016

Markov-Based Ranking Methods, Baback Vaziri

Open Access Dissertations

Ranking methods are an essential tool to help make decisions. This dissertation document examines different aspects of the theory and application of pairwise comparison ranking methods, specifically those that use Markov chains. First, a new method is developed to solve a traditional recruiting problem, and is shown to improve the predictive power of its ranking. Next, modifications are made to an existing method that theoretically improves the reliability, while maintaining the rank integrity. Last, a framework is developed that defines a fair and comprehensive ranking method, and several popular methods are evaluated in their ability to adhere to the said …


A Cross-Sectional And Mixed-Method Assessment Of Safety Culture And Safety Climate At A Regional Airline, Micah S. Walala May 2016

A Cross-Sectional And Mixed-Method Assessment Of Safety Culture And Safety Climate At A Regional Airline, Micah S. Walala

Open Access Dissertations

The researcher applied a mixed methods approach to conduct a cross-sectional assessment of the safety culture, safety climate, and SMS at a regional airline in the United States. Data collection techniques were comprised of interview, on-line-survey, and a focus group activity. Participants in the current study were maintenance technicians, flight attendants, dispatchers, pilots, and managers. Results indicated significant differences of perception of safety climate, safety culture, and Safety Management System between the maintenance technicians and flight attendants. The length of time a participant had worked at the subject airline and age of the participant appeared to be significant factors of …


Investigation Of Climate Variability And Climate Change Impacts On Corn Yield In The Eastern Corn Belt, Usa, Ruoyu Wang May 2016

Investigation Of Climate Variability And Climate Change Impacts On Corn Yield In The Eastern Corn Belt, Usa, Ruoyu Wang

Open Access Dissertations

The increasing demand for both food and biofuels requires more corn production at global scale. However, current corn yield is not able to meet bio-ethanol demand without jeopardizing food security or intensifying and expanding corn cultivation. An alternative solution is to utilize cellulose and hemi-cellulose from perennial grasses to fulfill the increasing demand for biofuel energy. A watershed level scenario analysis is often applied to figure out a sustainable way to strike the balance between food and fuel demands, and maintain environment integrity. However, a solid modeling application requires a clear understanding of crop responses under various climate stresses. This …


Concise Handbook For Temporary Traffic Control - Construction, Maintenance, And Utility Operations, Indiana Ltap, Ohio Department Of Transportation May 2016

Concise Handbook For Temporary Traffic Control - Construction, Maintenance, And Utility Operations, Indiana Ltap, Ohio Department Of Transportation

Indiana Local Technical Assistance Program (LTAP) Publications

This handbook gives the basic principles and provides examples for the design, application, installation, and maintenance of the various types of traffic control devices used in temporary traffic control or for incident management. Traffic control in roundabouts has been included in this version. The guidelines presented are in accordance with the standards provided within the Indiana Manual for Uniform Traffic Control Devices (IMUTCD). This handbook is based upon one created by the Ohio Department of Transportation, Guidelines for Traffic Control in Work Zones. Indiana LTAP expresses thanks to ODOT for their permission to reprint this material.


Pilot Source Study 2015: Us Regional Airline Pilot Hiring Background Characteristic Changes Consequent To Public Law 111-216 And The Faa First Officer Qualifications Rule, Elizabeth Bjerke, Guy Smith, Maryjo Smith, Cody Christensen, Thomas Carney, Paul Craig, Mary Niemczyk Apr 2016

Pilot Source Study 2015: Us Regional Airline Pilot Hiring Background Characteristic Changes Consequent To Public Law 111-216 And The Faa First Officer Qualifications Rule, Elizabeth Bjerke, Guy Smith, Maryjo Smith, Cody Christensen, Thomas Carney, Paul Craig, Mary Niemczyk

Journal of Aviation Technology and Engineering

This report is the first article in a series called Pilot Source Study 2015. Public Law (PL) 111-216, passed by the US Congress in 2010, and the subsequent FAA Regulation, Pilot Certification and Qualification Requirements for Air Carrier Operations Rule, abruptly changed the pilot hiring situation for US air carriers operating under 14 CFR Part 121. PL 111-216 became effective on August 1, 2013; thereafter, pilots were not eligible to be first officers in Part 121 air carriers unless they were certificated as Air Transport Pilots (ATP) with 1,500 hours of flight time, with some flight hour reductions for …


Assessing The Performance Of A Soy Methyl Ester -Polystyrene Topical Treatment To Extend The Service Life Of Concrete Structures, D'Shawn G. Thomas Apr 2016

Assessing The Performance Of A Soy Methyl Ester -Polystyrene Topical Treatment To Extend The Service Life Of Concrete Structures, D'Shawn G. Thomas

Open Access Theses

Experimental results show that soy methyl ester (SME), a derivative of soy bean oil, along with the incorporation of polystyrene (PS) is a non-toxic, biodegradable and renewable material that can be used effectively as a topical concrete surface treatment. While, concrete sealants and topical surface treatments can be used to extend to durability of concrete structures, it is difficult to predict the durability of concrete structures sealed with a sealant or topical surface treatment. This is due to a lack of necessary model inputs that can be used to address the durability of concrete structures treated with these materials. In …


Content-Based Image Analysis With Applications To The Multifunction Printer Imaging Pipeline And Image Databases, Cheng Lu Apr 2016

Content-Based Image Analysis With Applications To The Multifunction Printer Imaging Pipeline And Image Databases, Cheng Lu

Open Access Dissertations

Image understanding is one of the most important topics for various applications. Most of image understanding studies focus on content-based approach while some others also rely on meta data of images. Image understanding includes several sub-topics such as classification, segmentation, retrieval and automatic annotation etc., which are heavily studied recently. This thesis proposes several new methods and algorithms for image classification, retrieval and automatic tag generation. The proposed algorithms have been tested and verified in multiple platforms. For image classification, our proposed method can complete classification in real-time under hardware constraints of all-in-one printer and adaptively improve itself by online …


Multi-Axial Failure Of High-Performance Fiber During Transverse Impact, Matthew C. Hudspeth Apr 2016

Multi-Axial Failure Of High-Performance Fiber During Transverse Impact, Matthew C. Hudspeth

Open Access Dissertations

The effect of projectile nose geometry on ensuing wave development in high-performance yarns is explored during single yarn transverse impact. Special attention has been placed on visualizing the immediate region around the projectile-yarn contact site for 0.30-cal round, 0.30-cal fragment simulation projectiles (FSP), and razor blades using high-speed imaging. Kevlar® KM2, Dyneema®SK76 and AuTx have been impacted at velocities ranging from ∼100 m/s to ∼1200 m/s depending on projectile nose shape, with an emphasis set on determining the critical velocity wherein below said velocity significant development of wave propagation occurs and above said velocity the yarn fails immediately upon impact. …


Preliminary Design Tools In Turbomachinery: Non-Uniformly Spaced Blade Rows, Multistage Interaction, Unsteady Radial Waves, And Propeller Horizontal-Axis Turbine Optimization, Yujun Leng Apr 2016

Preliminary Design Tools In Turbomachinery: Non-Uniformly Spaced Blade Rows, Multistage Interaction, Unsteady Radial Waves, And Propeller Horizontal-Axis Turbine Optimization, Yujun Leng

Open Access Dissertations

Turbomachinery flow fields are inherently unsteady and complex which makes the related CFD analyses computationally intensive. Physically based preliminary design tools are desirable for parametric studies early in the design stage, and to provide deep physical insight and a good starting point for the later CFD analyses. Four analytical/semi-analytical models are developed in this study: 1) a generalized flat plate cascade model for investigating the unsteady aerodynamics of a blade row with non-uniformly spaced blades; 2) a multistage interaction model for investigating rotor-stator interactions; 3) an analytical solution for quantifying the impeller wake convection and pressure wave propagating between a …


Grounding Robot Motion In Natural Language And Visual Perception, Scott Alan Bronikowski Apr 2016

Grounding Robot Motion In Natural Language And Visual Perception, Scott Alan Bronikowski

Open Access Dissertations

The current state of the art in military and first responder ground robots involves heavy physical and cognitive burdens on the human operator while taking little to no advantage of the potential autonomy of robotic technology. The robots currently in use are rugged remote-controlled vehicles. Their interaction modalities, usually utilizing a game controller connected to a computer, require a dedicated operator who has limited capacity for other tasks.

I present research which aims to ease these burdens by incorporating multiple modes of robotic sensing into a system which allows humans to interact with robots through a natural-language interface. I conduct …


Development And Evaluation Of A Watershed-Scale Hybrid Hydrologic Model, Younghyun Cho Apr 2016

Development And Evaluation Of A Watershed-Scale Hybrid Hydrologic Model, Younghyun Cho

Open Access Dissertations

A watershed-scale hybrid hydrologic model (Distributed-Clark), which is a lumped conceptual and distributed feature model, was developed to predict spatially distributed short- and long-term rainfall runoff generation and routing using relatively simple methodologies and state-of-the-art spatial data in a GIS environment. In Distributed-Clark, spatially distributed excess rainfall estimated with the SCS curve number method and a GIS-based set of separated unit hydrographs (spatially distributed unit hydrograph) are utilized to calculate a direct runoff flow hydrograph, and time-varied SCS CN values and conditional unit hydrograph approach for different runoff depth-based flow convolution are also used to compute long-term rainfall-runoff flow hydrographs. …


Asphalt Pavement Preservation Using Rejuvenating Fog Seals, Ammanuiel A. Kebede Apr 2016

Asphalt Pavement Preservation Using Rejuvenating Fog Seals, Ammanuiel A. Kebede

Open Access Theses

Fog seal is a type of treatment that uses a diluted asphalt emulsion to seal and protect an existing asphalt surface from a variety of distresses. Fog seal is sprayed on top of an asphalt pavement surface to improve and protect it from further cracking and raveling. Rejuvenator is also a type of treatment that penetrates into the asphalt pavement and restores its original viscoelastic properties. Similarly, like fog seal, rejuvenators can be sprayed on top of an asphalt pavement surface. The use of rejuvenators has grown rapidly in the past decade. However, little is known about the actual effectiveness …


Ibeacon Based Proximity And Indoor Localization System, Faheem Faheem Apr 2016

Ibeacon Based Proximity And Indoor Localization System, Faheem Faheem

Open Access Theses

User location can be leveraged to provide a wide range of services in a variety of indoor locations including retails stores, hospitals, airports, museums and libraries etc. The widescale proliferation of user devices such as smart phones and the interconnectivity among different entities, powered by Internet of Things (IoT), makes user device-based localization a viable approach to provide Location Based Services (LBS). Location based services can be broadly classified into 1) Proximity based services that provides services based on a rough estimate of users distance to any entity, and 2) Indoor localization that locates a user's exact location in the …


Cosmic Ray Muons For Spent Nuclear Fuel Monitoring, Stylianos Chatzidakis Apr 2016

Cosmic Ray Muons For Spent Nuclear Fuel Monitoring, Stylianos Chatzidakis

Open Access Dissertations

There is a steady increase in the volume of spent nuclear fuel stored on-site (at reactor) as currently there is no permanent disposal option. No alternative disposal path is available and storage of spent nuclear fuel in dry storage containers is anticipated for the near future. In this dissertation, a capability to monitor spent nuclear fuel stored within dry casks using cosmic ray muons is developed. The motivation stems from the need to investigate whether the stored content agrees with facility declarations to allow proliferation detection and international treaty verification. Cosmic ray muons are charged particles generated naturally in the …


Learning From Minimally Labeled Data With Accelerated Convolutional Neural Networks, Aysegul Dundar Apr 2016

Learning From Minimally Labeled Data With Accelerated Convolutional Neural Networks, Aysegul Dundar

Open Access Dissertations

The main objective of an Artificial Vision Algorithm is to design a mapping function that takes an image as an input and correctly classifies it into one of the user-determined categories. There are several important properties to be satisfied by the mapping function for visual understanding. First, the function should produce good representations of the visual world, which will be able to recognize images independently of pose, scale and illumination. Furthermore, the designed artificial vision system has to learn these representations by itself. Recent studies on Convolutional Neural Networks (ConvNets) produced promising advancements in visual understanding. These networks attain significant …


Effect Of Bioenergy Crops And Fast Growing Trees On Hydrology And Water Quality In The Little Vermilion River Watershed, Tian Guo Apr 2016

Effect Of Bioenergy Crops And Fast Growing Trees On Hydrology And Water Quality In The Little Vermilion River Watershed, Tian Guo

Open Access Dissertations

Energy security and sustainability require a suite of biomass crops, including woody species. Short rotation woody crops (SRWCs) such as Populus have great potential as biofuel feedstocks. Quantifying biomass yields of bioenergy crop and hydrologic and water quality responses to growth is important should it be widely planted in the Midwestern U.S. Subsurface tile drainage systems enable the Midwest area to become highly productive agricultural lands, but also create environmental problems like nitrate-N contamination of the water it drains. The Soil and Water Assessment Tool (SWAT) has been used to model watersheds with tile drainage, but the new tile drainage …


Representation And Control Of Coordinated-Motion Tasks For Human-Robot Systems, Hyungju Andy Park Apr 2016

Representation And Control Of Coordinated-Motion Tasks For Human-Robot Systems, Hyungju Andy Park

Open Access Dissertations

It is challenging for robots to perform various tasks in a human environment. This is because many human-centered tasks require coordination in both hands and may often involve cooperation with another human. Although human-centered tasks require different types of coordinated movements, most of the existing methodologies have focused only on specific types of coordination. This thesis aims at the description and control of coordinated-motion tasks for human-robot systems; i.e., humanoid robots as well as multi-robot and human-robot systems.

First, for bimanually coordinated-motion tasks in dual-manipulator systems, we propose the Extended-Cooperative-Task-Space (ECTS) representation, which extends the existing Cooperative-Task-Space (CTS) representation based …


Learning In Vision And Robotics, Daniel P. Barrett Apr 2016

Learning In Vision And Robotics, Daniel P. Barrett

Open Access Dissertations

I present my work on learning from video and robotic input. This is an important problem, with numerous potential applications. The use of machine learning makes it possible to obtain models which can handle noise and variation without explicitly programming them. It also raises the possibility of robots which can interact more seamlessly with humans rather than only exhibiting hard-coded behaviors. I will present my work in two areas: video action recognition, and robot navigation. First, I present a video action recognition method which represents actions in video by sequences of retinotopic appearance and motion detectors, learns such models automatically …


Incorporation Of Gnss Multipath To Improve Autonomous Rendezvous, Docking And Proximity Operations In Space, Benjamin W. Ashman Apr 2016

Incorporation Of Gnss Multipath To Improve Autonomous Rendezvous, Docking And Proximity Operations In Space, Benjamin W. Ashman

Open Access Dissertations

Automated rendezvous and docking (AR&D;) operations are important for many future space missions, such as the resupply of space stations, repair and refueling of large satellites, and active removal of orbital debris. These operations depend critically on accurate, real-time knowledge of the relative position and velocity between two space vehicles. Unfortunately, Global Navigation Satellite System (GNSS) capabilities remain severely limited in close proximity to large space structures due to significant multipath effects and signal blockage. Although GNSS is used for the initial stages of approach, other instruments such as laser, radar and vision-based systems, are required to augment GNSS during …


Artificial Neural Networks For Wireless Structural Control, Ghazi Binarandi Apr 2016

Artificial Neural Networks For Wireless Structural Control, Ghazi Binarandi

Open Access Theses

We live in an age when people desire taller buildings and longer bridges. These increasing demands of more flexible structures challenge civil engineers to ensure structural safety in the state where they are more prone to extreme dynamic loading, such as earthquakes. Extensive wiring required in traditional structural control applications may be expensive and inconvenient, especially for large scale structures. To improve the scalability, wireless sensors offer a promising alternative. However, the presence of time delay and data loss in a wireless sensor network can potentially reduce the performance of the control system. Here an artificial neural network is proposed …


Magnetic Equivalent Circuit Based Permanent Magnet Characterization, Vinicius Cabral Do Nascimento Apr 2016

Magnetic Equivalent Circuit Based Permanent Magnet Characterization, Vinicius Cabral Do Nascimento

Open Access Theses

This thesis sets forth a permanent magnet characterization fixture and procedure. The work begins with a review of the state of the art in permanent magnet characterization. It then sets forth a new characterization fixture. The proposed system relies on the use of low cost sensors to perform the necessary measurements, which consists of search coils, hall sensors, and current probes. A magnetic equivalent circuit is set forth to analyze the fixture and for use in identification of permanent magnet parameters. The characterization procedure is based on an experimentally defined magnetic equivalent circuit. An experimental approach to model the tester …