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Full-Text Articles in Engineering

Aligned Carbon Nanotube Arrays Bonded To Solid Graphite Substrates: Thermal Analysis For Future Device Cooling Applications, Betty T. Quinton, Levi Elston, James D. Scofield, Sharmila M. Mukhopadhyay May 2018

Aligned Carbon Nanotube Arrays Bonded To Solid Graphite Substrates: Thermal Analysis For Future Device Cooling Applications, Betty T. Quinton, Levi Elston, James D. Scofield, Sharmila M. Mukhopadhyay

Mechanical and Materials Engineering Faculty Publications

Carbon nanotubes (CNTs) are known for high thermal conductivity and have potential use as nano-radiators or heat exchangers. This paper focuses on the thermal performance of carpet-like arrays of vertically aligned CNTs on solid graphite substrates with the idea of investigating their behavior as a function of carpet dimensions and predicting their performance as thermal interface material (TIM) for electronic device cooling. Vertically aligned CNTs were grown on highly oriented pyrolytic graphite (HOPG) substrate, which creates a robust and durable all-carbon hierarchical structure. The multi-layer thermal analysis approach using Netzsch laser flash analysis system was used to evaluate their performance ...


In Situ Defect Detection Using Three Color Spectroscopy In Laser Powder Bed Additive Manufacturing, Andrew Drieling Apr 2018

In Situ Defect Detection Using Three Color Spectroscopy In Laser Powder Bed Additive Manufacturing, Andrew Drieling

The University Honors Program

Additive Manufacturing (AM) provides a way to create parts that would be extremely difficult or impossible with conventional manufacturing processes. However, AM also introduces defects, which are detrimental to the mechanical performance. These defects are potentially unknown until post-processing inspection and testing, wasting time and resources on an unusable part or initiating unexpected failure. Historically, spectroscopy has successfully been used for in situ monitoring of laser welding, using changing parameters in the generated plume to predict defects. In situ monitoring using a visible spectrometer for fabrication of Alloy 718 on a test bed laser powder bed fusion system is performed ...


Modeling And Visualization Of Uncertainty-Aware Geometries Using Multi-Variate Normal Distributions, Christina Gillman, Thomas Wischgoll, Bernd Hamann, James Ahrens Apr 2018

Modeling And Visualization Of Uncertainty-Aware Geometries Using Multi-Variate Normal Distributions, Christina Gillman, Thomas Wischgoll, Bernd Hamann, James Ahrens

Computer Science and Engineering Faculty Publications

Many applications are dealing with geometric data that are affected by uncertainty. It is important to analyze, visualize, and understand the properties of uncertain geometry. We present a methodology to model uncertain geometry based on multi-variate normal distributions. In addition, we propose a visualization technique to represent a hull for uncertain geometry capturing a user-defined percentage of the underlying uncertain geometry. To show the effectiveness of our approach, we have modeled and visualized uncertain datasets from different applications.


Wright State University's Symposium Of Student Research, Scholarship & Creative Activities From Friday April 13, 2017, Wright State University Apr 2018

Wright State University's Symposium Of Student Research, Scholarship & Creative Activities From Friday April 13, 2017, Wright State University

Browse All Celebration of Research, Scholarship, and Creative Activities Materials

The student abstract booklet is a compilation of abstracts from students' oral and poster presentations at Wright State University's Symposium of Student Research, Scholarship & Creative Activities on April 13, 2018.


Usability Assessment For Caregiver Behavior Analysis Using Gaming Technology, Alexandrea C. Oliver, Tanvi Banerjee, Jennifer Hughes, Noah L. Schroeder Mar 2018

Usability Assessment For Caregiver Behavior Analysis Using Gaming Technology, Alexandrea C. Oliver, Tanvi Banerjee, Jennifer Hughes, Noah L. Schroeder

Computer Science and Engineering Faculty Publications

The proposed research focuses on developing a mobile application for Android systems that will detect changes in behavior and activity patterns of those who are primary caregivers for dementia patients. This application will be used to detect fluctuation in the behavior and the task performance of the caregivers as a measure of caregiver stress. By detecting these changes in behavior, the goal is to analyze the effects of caregiving to evaluate caregiver burnout. A usability study was conducted for this application to find the optimal design factors and features that benefit the target user: the caregiver.

The purpose of this ...


An Uncertainty-Aware Workflow For Keyhole Surgery Planning Using Hierarchical Image Semantics, Christina Gillmann, Robin G.C. Maack, Tobias Post, Thomas Wischgoll, Hans Hagen Feb 2018

An Uncertainty-Aware Workflow For Keyhole Surgery Planning Using Hierarchical Image Semantics, Christina Gillmann, Robin G.C. Maack, Tobias Post, Thomas Wischgoll, Hans Hagen

Computer Science and Engineering Faculty Publications

Keyhole surgeries become increasingly important in clinical daily routine as they help minimizing the damage of a patient's healthy tissue. The planning of keyhole surgeries is based on medical imaging and an important factor that influences the surgeries' success. Due to the image reconstruction process, medical image data contains uncertainty that exacerbates the planning of a keyhole surgery. In this paper we present a visual workfiow that helps clinicians to examine and compare different surgery paths as well as visualizing the patients' affected tissue. The analysis is based on the concept of hierarchical image semantics, that segment the underlying ...


Trust In Visualization (And What It Has To Do With Theory), Thomas Wischgoll Jan 2018

Trust In Visualization (And What It Has To Do With Theory), Thomas Wischgoll

Computer Science and Engineering Faculty Publications

There are different issues with trust involved when working with domain experts to visualize their data. There may be limitations with the data that require special precautions, such as sensitivity or security limitations. It may have taken a lot of effort to collect or create the data so that a certain level of trust is required for the domain expert to share the data. At the same time, the domain expert needs to be able to trust in the final visualization results. This presentation discusses these issues with trust and what requirements for a theoretical foundation this results in. Furthermore ...


Developing A High-Dimensional Dataset Of The Changes In Ion Channels Expression Level At The Cholinergic Boutons In Amyotrophic Lateral Sclerosis, Joshua Harris Jan 2018

Developing A High-Dimensional Dataset Of The Changes In Ion Channels Expression Level At The Cholinergic Boutons In Amyotrophic Lateral Sclerosis, Joshua Harris

The University Honors Program

ALS, or Amyotrophic Lateral Sclerosis, is a neurodegenerative disease that causes motor neuron degeneration. Affecting nerve cells in the brain and spinal cord, this disease eventually leads to respiratory muscle failure and death. Although ALS is fairly uncommon, our lack of information on how ALS develops drives the need for further study. In the Neuro Engineering, Rehabilitation, and Degeneration laboratory at Wright State University, immunohistochemical data has been collected on a mouse model (SOD1-G93A) throughout their lifespan to better examine the neurological effects of ALS. To better organize and interpret the data, a high-dimensional dataset was created in this project ...


Evaluation Of Consumer Drone Control Interface, Thomas William Merrell Jan 2018

Evaluation Of Consumer Drone Control Interface, Thomas William Merrell

Browse all Theses and Dissertations

The development and use of consumer grade drones is becoming a larger part of our society for many different applications. There has been a great amount of discussion and constant review of proper operation of consumer drones including proper methods of control. In turn, regulation of such devices has been inconsistent. This study aims to better understand the effects of the three primary control interface methods (line of sight, video aided, and first-person view) on flight performance, situational awareness, and perceived mental workload of the operator. Secondarily, this study aims to provide design recommendations for future interfaces. This study shows ...


M1 To M2 Macrophage Induction Using Retinoic Acid And Mesenchymal Stem Cells Loaded On An Electrospun Pullulan/Gelatin Scaffold To Promote Healing Of Chronic Wounds, Kaivon Assani Jan 2018

M1 To M2 Macrophage Induction Using Retinoic Acid And Mesenchymal Stem Cells Loaded On An Electrospun Pullulan/Gelatin Scaffold To Promote Healing Of Chronic Wounds, Kaivon Assani

Browse all Theses and Dissertations

Modulation of macrophage polarization is required for effective tissue repair and regenerative therapies. Conversion of macrophages from inflammatory M1 to fibrotic M2 phenotype could help in diseases such as chronic wound which are stuck in inflammatory state. During the inflammatory phase, macrophages are of the inflammatory phenotype (M1) and distribute pro-inflammatory cytokines including TNF-a and IL1[beta] which are microbicidal and recruit/activate cells. In normal wound healing macrophages then switch to a fibrotic phenotype (M2) promoting wound closure by angiogenesis, and matrix deposition. Chronic wounds are a major biological and financial burden to both patients and the health care ...


Building An Abstract-Syntax-Tree-Oriented Symbolic Execution Engine For Php Programs, Jin Huang Jan 2018

Building An Abstract-Syntax-Tree-Oriented Symbolic Execution Engine For Php Programs, Jin Huang

Browse all Theses and Dissertations

This thesis presents the design, implementation, and evaluation of an abstract-syntax-tree-oriented symbolic execution engine for the PHP programming language. As a symbolic execution engine, our system emulate the execution of a PHP program by assuming that all inputs are with symbolic rather than concrete values. While our system inherits the basic definition of symbolic execution, it fundamentally differs from existing symbolic execution implementations that mainly leverage intermediate representation (IRs) to operate. Specifically, our system directly takes the abstract syntax tree (AST) of a program as input and subsequently interprets this AST. Performing symbolic execution using AST offers unique advantages. First ...


Image Stitching And Matching Tool In The Automated Iterative Reverse Engineer (Aire) Integrated Circuit Analysis Suite, David C. Bowman Jan 2018

Image Stitching And Matching Tool In The Automated Iterative Reverse Engineer (Aire) Integrated Circuit Analysis Suite, David C. Bowman

Browse all Theses and Dissertations

Due to current market forces, leading-edge semiconductor fabrication plants have moved outside of the US. While this is not a problem at first glance, when it comes to security-sensitive applications, over-production, device cloning, or design alteration becomes a possibility. Since these vulnerabilities exist during the fabrication phase, a Reverse Engineering (RE) step must be introduced to help ensure secure device operation. This thesis proposes several unique methods and a collection of tools to ensure trust assurance in integrated circuit design by detecting fabrication flaws and possible hardware Trojans using several image processing techniques; fused into a singular view of the ...


Real-Time Path Planning And Obstacle Avoidance For Mobile Robots With Actuator Faults, Ravindra Vibha Bellur Jan 2018

Real-Time Path Planning And Obstacle Avoidance For Mobile Robots With Actuator Faults, Ravindra Vibha Bellur

Browse all Theses and Dissertations

In this research, a fault-tolerant path planning and obstacle avoidance algorithm is implemented for mobile ground robots. The fault-tolerant system architecture consists of the following three components: (1) an online fault diagnosis module for detecting and estimating actuator faults in the mobile robot; (2) a localization and mapping module for dynamic terrain mapping and obstacle detection; (3) a path planning and obstacle avoidance module for generating way points from a given point to the desired destination, avoiding the detected obstacles and moving along these way points. The online fault diagnostic information is used to compensate for the effect of faults ...


A Simulation Method For Studying Effects Of Site-Specific Clutter On Sar-Gmti Performance, Marcus James Campbell Jan 2018

A Simulation Method For Studying Effects Of Site-Specific Clutter On Sar-Gmti Performance, Marcus James Campbell

Browse all Theses and Dissertations

Synthetic aperture radar (SAR) is an invaluable tool for detection of ground moving targets when combined with processing techniques of ground moving target indication (GMTI). This work investigates a simulation methodology for studying impact of site-specific ground clutter on SAR-GMTI performance. A terrain model is proposed and is based on digital terrain elevation data (DTED) and national land-use land-cover data (NLCD) as provided by the US Geological Survey. The proposed physical optics simulation method capitalizes on high-fidelity digital target models in combination with the proposed terrain model. SAR phase history is generated for a moving commercial target in situ of ...


Design Of A Novel Tissue Culture System To Subject Aortic Tissue To Multidirectional Bicuspid Aortic Valve Wall Shear Stress, Janet Liu Jan 2018

Design Of A Novel Tissue Culture System To Subject Aortic Tissue To Multidirectional Bicuspid Aortic Valve Wall Shear Stress, Janet Liu

Browse all Theses and Dissertations

Blood vessels experience complex hemodynamics marked by three-dimensionality and pulsatility. Arterial endothelial cells interact with the characteristics of the fluid wall shear stress (WSS) to maintain homeostasis or promote disease states. In particular, the bicuspid aortic valve (BAV), a congenital heart valve anatomy consisting of two leaflets instead of three, is associated with aortic complications presumably promoted by hemodynamic abnormalities. While devices have been used to test this hypothesis, their capabilities are limited to the generation of time-varying WSS magnitude in one direction. However, the increased flow helicity generated by BAVs in the aorta is expected to result in increased ...


In Vitro Assessment Of The Effects Of Valvular Stenosis On Aorta Hemodynamics And Left Ventricular Function, Ashish Madan Jan 2018

In Vitro Assessment Of The Effects Of Valvular Stenosis On Aorta Hemodynamics And Left Ventricular Function, Ashish Madan

Browse all Theses and Dissertations

Calcific aortic stenosis (CAS) is the most common valvular heart disease and is associated with aortopathy and ventricular dysfunction. Hemodynamic alterations due CAS could affect the aorta lining (endothelium), that is in direct contact with the blood, triggering adverse biological responses that may possibly cause aortic dilation and dissection. Also, CAS could impose excessive ventricular load leading to ventricular wall thickening, thus putting an individual at a higher risk of heart attack or stroke. These pathophysiological effects of CAS are highly dependent on the degree of calcification. However, the impact of CAS development on aorta flow and left ventricular workload ...


Analysis Of Evolutionary Algorithms In The Control Of Path Planning Problems, Pavlos Androulakakis Jan 2018

Analysis Of Evolutionary Algorithms In The Control Of Path Planning Problems, Pavlos Androulakakis

Browse all Theses and Dissertations

The purpose of this thesis is to examine the ability of evolutionary algorithms (EAs) to develop near optimal solutions to three different path planning control problems. First, we begin by examining the evolution of an open-loop controller for the turn-circle intercept problem. We then extend the evolutionary methodology to develop a solution to the closedloop Dubins Vehicle problem. Finally, we attempt to evolve a closed-loop solution to the turn constrained pursuit evasion problem. For each of the presented problems, a custom controller representation is used. The goal of using custom controller representations (as opposed to more standard techniques such as ...


Measurement Of Unsteady Characteristics Of Endwall Vortices Using Surface-Mounted Hot-Film Sensors, Emma Michelle Veley Jan 2018

Measurement Of Unsteady Characteristics Of Endwall Vortices Using Surface-Mounted Hot-Film Sensors, Emma Michelle Veley

Browse all Theses and Dissertations

High-lift low-pressure turbine blades produce significant losses at the junction with the endwall. The losses are caused by several complex three-dimensional vortical flow structures, which interact with the blade suction surface boundary layer. This study investigates the unsteady characteristics of these endwall flow structures on a highly loaded research profile and the adjacent endwall using surface-mounted hot-film sensors. Experiments were conducted in a low-speed linear cascade wind tunnel. The front-loaded blade profile was subjected to three different inlet conditions, consisting of two turbulence levels, and three incoming boundary layer thicknesses. Multiple surface-mounted hot-film sensors were installed throughout the passage. This ...


Impact Of Near-Field-To-Far-Field Transformation On Sar Images Formed In An Indoor Non-Anechoic Environment, Jacob D. Compaleo Jan 2018

Impact Of Near-Field-To-Far-Field Transformation On Sar Images Formed In An Indoor Non-Anechoic Environment, Jacob D. Compaleo

Browse all Theses and Dissertations

This work investigates the impact of the near-field-to-far-field transformation (NFFFT) algorithm on phase history measurement collections completed in the Sensors and Signals Exploitation Laboratory (SSEL). SSEL is an indoor non-anechoic environ- ment that is at risk to some measurement interferences such as multiple bounces. Complete 360-degree phase history measurements of scale model aircraft are con- ducted at varying range values within the near-field limit. These measurements are calibrated with the Mie series scattering solution for a sphere. After calibration, the measurements are transformed using the NFFFT, with radar cross-section (RCS) estimated. RCS of the transformed data is compared with the ...


Content-Based Clustering And Visualization Of Social Media Text Messages, Sydney A. Barnard Jan 2018

Content-Based Clustering And Visualization Of Social Media Text Messages, Sydney A. Barnard

Browse all Theses and Dissertations

Although Twitter has been around for more than ten years, crisis management agencies and first response personnel are not able to fully use the information this type of data provides during a crisis or natural disaster. This thesis addresses clustering and visualizing social media data by textual similarity, rather than by only time and location, as a tool for first responders. This thesis presents a tool that automatically clusters geotagged text data based on their content and displays the clusters and their locations on the map. It allows at-a-glance information to be displayed throughout the evolution of a crisis. For ...


A Semantically Enhanced Approach To Identify Depression-Indicative Symptoms Using Twitter Data, Ankita Saxena Jan 2018

A Semantically Enhanced Approach To Identify Depression-Indicative Symptoms Using Twitter Data, Ankita Saxena

Browse all Theses and Dissertations

According to the World Health Organization, more than 300 million people suffer from Major Depressive Disorder (MDD) worldwide. PHQ-9 is used to screen and diagnose MDD clinically and identify its severity. With the unprecedented growth and enthusiastic acceptance of social media such as Twitter, a large number of people have come to share their feelings and emotions on it openly. Each tweet can indicate a user's opinion, thought or feeling. A tweet can also indicate multiple symptoms related to PHQ-9. Identifying PHQ-9 symptoms indicated by a tweet can provide crucial information about a user regarding his/her depression diagnosis ...


A Twitter-Based Study For Understanding Public Reaction On Zika Virus, Roopteja Muppalla Jan 2018

A Twitter-Based Study For Understanding Public Reaction On Zika Virus, Roopteja Muppalla

Browse all Theses and Dissertations

In recent times, social media platforms like Twitter have become more popular and people have become more interactive and responsive than before. People often react to every news in real-time and within no-time, the information spreads rapidly. Even with viral diseases like Zika, people tend to share their opinions and concerns on social media. This can be leveraged by the health officials to track the disease in real-time thereby reducing the time lag due to traditional surveys. A faster and accurate detection of the disease can allow health officials to understand people's opinion of the disease and take necessary ...


Multiscale Modeling Of Hemodynamics In Human Vessel Network And Its Applications In Cerebral Aneurysms, Hongtao Yu Jan 2018

Multiscale Modeling Of Hemodynamics In Human Vessel Network And Its Applications In Cerebral Aneurysms, Hongtao Yu

Browse all Theses and Dissertations

Three-dimensional (3D) simulation of patient-specific morphological models has been widely used to provide the hemodynamic information of individual patients, such as wall shear stress (WSS), oscillatory shear index (OSI), and flow patterns, etc. Since patient-specific morphological segment was only restricted locally, boundary conditions (BCs) are required to implement the CFD simulation. Direct measurements of the flow and pressure waveforms were often required as input BCs for 3D CFD simulations of patient-specific models. However, as the morphology develops, the feedback from this topological deformation may lead to BCs being altered, and hence without this feedback, the flow characteristics of the morphology ...


Demonstrating The Functionality And Efficacy Of Blockchain-Based System In Healthcare Using Simulation Tools, Jad S. Mubaslat Jan 2018

Demonstrating The Functionality And Efficacy Of Blockchain-Based System In Healthcare Using Simulation Tools, Jad S. Mubaslat

Browse all Theses and Dissertations

Blockchain and cryptocurrencies have been a rapidly growing industry and area of academic research since Bitcoin's launch in early 2009. Blockchains have already been applied in spaces outside of finance, such as healthcare. This work explores the Bitcoin blockchain and a blockchain-based care coordination system through the use of modeling and simulation tools. Two agent based models are constructed: one to represent the Bitcoin blockchain, and a second to represent a blockchain-based care coordination system, MDChain. Insight is provided that is relevant to current issues within the Bitcoin community and predictions are made as to its future. The feasibility ...


A Stochastic Petri Net Reverse Engineering Methodology For Deep Understanding Of Technical Documents, Giorgia Rematska Jan 2018

A Stochastic Petri Net Reverse Engineering Methodology For Deep Understanding Of Technical Documents, Giorgia Rematska

Browse all Theses and Dissertations

Systems Reverse Engineering has gained great attention over time and is associated with numerous different research areas. The importance of this research derives from several technological necessities. Security analysis and learning purposes are two of them and can greatly benefit from reverse engineering. More specifically, reverse engineering of technical documents for deeper automatic understanding is a research area where reverse engineering can contribute a lot. In this PhD dissertation we develop a novel reverse engineering methodology for deep understanding of architectural description of digital hardware systems that appear in technical documents. Initially, we offer a survey on reverse engineering of ...


Domain-Specific Knowledge Extraction From The Web Of Data, Sarasi Lalithsena Jan 2018

Domain-Specific Knowledge Extraction From The Web Of Data, Sarasi Lalithsena

Browse all Theses and Dissertations

Domain knowledge plays a significant role in powering a number of intelligent applications such as entity recommendation, question answering, data analytics, and knowledge discovery. Recent advances in Artificial Intelligence and Semantic Web communities have contributed to the representation and creation of this domain knowledge in a machine-readable form. This has resulted in a large collection of structured datasets on the Web which is commonly referred to as the Web of data. The Web of data continues to grow rapidly since its inception, which poses a number of challenges in developing intelligent applications that can benefit from its use. Majority of ...


Fabrication And Characterizations Of Lagp/Peo Composite Electrolytes For All Solid-State Lithium-Ion Batteries, Jeremy J. Lee Jan 2018

Fabrication And Characterizations Of Lagp/Peo Composite Electrolytes For All Solid-State Lithium-Ion Batteries, Jeremy J. Lee

Browse all Theses and Dissertations

With the rise of electric vehicles and increasing dependence on mobile electronics, the demands for lithium-ion batteries have followed in tandem for their high energy and power densities. However, traditional lithium-ion batteries consisting of liquid electrolytes have limited operating temperatures and are susceptible to ignition and subsequent fires. Recently, battery research has diverged into solid state chemistry to address the aforementioned issues. In this research, we systematically investigate a series of ceramic/polymer lithium-ion conducting composite electrolytes, i.e. Li1.4Al0.4Ge1.6(PO4)3 /lithiated polyethylene oxide (LAGP/PEO). Lithiated PEO was prepared with two different lithium salts, LiBF4 ...


Augmenting Incident Command System For Improved Emergency Response, Meenakshi Nagarajan Jan 2018

Augmenting Incident Command System For Improved Emergency Response, Meenakshi Nagarajan

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Incident Command System provides a framework for commanders to manage an incident. However, maintaining good situation awareness in an emergency situation is often challenging to the Incident Commander. Stress may result in task fixation which may cause the commander to miss critical information and can eventually lead to poor decisions. The proposed augmented decision support system, with an integrated knowledge base, enhances the commander's decision making and situation awareness by presenting the information that may have been missed. The system has been evaluated to investigate its utility in chemical hazard scenarios. The system was used by experienced Incident Commanders ...


Slim Embedding Layers For Recurrent Neural Language Models, Zhongliang Li Jan 2018

Slim Embedding Layers For Recurrent Neural Language Models, Zhongliang Li

Browse all Theses and Dissertations

Recurrent neural language (RNN) models are the state-of-the-art method for language modeling. When the vocabulary size is large, the space taken to store the model parameters becomes the bottleneck for the use of these type of models. We introduce a simple space compression method that stochastically shares the structured parameters at both the input and output embedding layers of RNN models to significantly reduce the size of model parameters, but still compactly represents the original input and the output embedding layers. The method is easy to implement and tune. Experiments on several data sets show that the new method achieves ...


Measuring Goal Similarity Using Concept, Context And Task Features, Vahid Eyorokon Jan 2018

Measuring Goal Similarity Using Concept, Context And Task Features, Vahid Eyorokon

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Goals can be described as the user's desired state of the agent and the world and are satisfied when the agent and the world are altered in such a way that the present state matches the desired state. For physical agents, they must act in the world to alter it in a series of individual atomic actions. Traditionally, agents use planning to create a chain of actions each of which altering the current world state and yielding a new one until the final action yields the desired goal state. Once this goal state has been achieved, the goal is ...