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Full-Text Articles in Engineering

Data-Driven Network-Centric Threat Assessment, Dae Wook Kim Jan 2017

Data-Driven Network-Centric Threat Assessment, Dae Wook Kim

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As the Internet has grown increasingly popular as a communication and information sharing platform, it has given rise to two major types of Internet security threats related to two primary entities: end-users and network services. First, information leakages from networks can reveal sensitive information about end-users. Second, end-users systems can be compromised through attacks on network services, such as scanning-and-exploit attacks, spamming, drive-by downloads, and fake anti-virus software. Designing threat assessments to detect these threats is, therefore, of great importance, and a number of the detection systems have been proposed. However, these existing threat assessment systems face significant challenges in …

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Design And Testing Of Scalable 3d-Printed Cellular Structures Optimized For Energy Absorption, Sagar Dilip Sangle Jan 2017

Design And Testing Of Scalable 3d-Printed Cellular Structures Optimized For Energy Absorption, Sagar Dilip Sangle

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Sandwich panel structures are widely used due to their high compressive and flexural stiffness and strength-to-weight ratios, good vibration damping, and low through-thickness thermal conductivity. These structures consist of solid face sheets and low-density cellular core structures that are often based upon honeycomb topologies. Interest in additive manufacturing (AM), popularly known as 3D printing (3DP), has rapidly grown in past few years. The 3DP method is a layer-by-layer approach for the fabrication of 3D objects. Hence, it is very easy to fabricate complex structures with complex internal features that cannot be manufactured by any other fabrication processes. Due to the …

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On The Thermal And Contact Fatigue Behavior Of Gear Contacts Under Tribo-Dynamic Condition, Anusha Anisetti Jan 2017

On The Thermal And Contact Fatigue Behavior Of Gear Contacts Under Tribo-Dynamic Condition, Anusha Anisetti

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Gears are vital power transmitting mechanical components, in both automotive and aerospace applications, and commonly operate within relatively high rotational speed ranges. Therefore, the dynamic behavior of gears is inevitable and can be quite significant under certain circumstances. The gear dynamics introduces not only noises and vibrations, but also large tooth force amplitudes, and consequently large amplitudes of bending stresses and contact stresses, and high surface temperatures, promoting the failures of tooth bending fatigue, contact fatigue, and scuffing. This study focuses on the mechanism by which the gear dynamic responses affect the flash temperature rise and contact fatigue life using …

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Characterizing Concepts In Taxonomy For Entity Recommendations, Siva Kumar Cheekula Jan 2017

Characterizing Concepts In Taxonomy For Entity Recommendations, Siva Kumar Cheekula

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Entity recommendation systems are enormously popular on the Web. These systems harness manually crafted taxonomies for improving recommendations. For example, Yahoo created the Open Directory Project for search and recommendation, and Amazon utilizes its own product taxonomy. While these taxonomies are of high quality, it is a labor and time-intensive process to manually create and keep them up to date. Instead, in this era ofWeb 2.0 where users collaboratively create large amounts of information on the Web, it is possible to utilize user-generated content to automatically generate good quality taxonomies. However, harnessing such taxonomies for entity recommendations has not been …

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Dynamic Modeling And Simulation Of A Variable Cycle Turbofan Engine With Controls, Robert W. Buettner Jan 2017

Dynamic Modeling And Simulation Of A Variable Cycle Turbofan Engine With Controls, Robert W. Buettner

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Next generation aircraft (especially combat aircraft) will include more technology and capability than ever before. This increase in technology comes at the price of higher electrical power requirements and increased waste heat that must be removed from components to avoid overheating induced shutdowns. To help combat the resulting power and thermal management problem, a vehicle level power and thermal management design and optimization toolset was developed in MATLAB®/Simulink®. A dynamic model of a three-stream variable cycle engine was desired to add to the capabilities of the power and thermal management toolset. As an intermediate step to this goal, the dynamic …

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Design Of An 8-Bit Successive Approximation Pipelined Analog To Digital Converter (Sap-Adc) In 90 Nm Cmos, Vivek Kotti Jan 2017

Design Of An 8-Bit Successive Approximation Pipelined Analog To Digital Converter (Sap-Adc) In 90 Nm Cmos, Vivek Kotti

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Analog to Digital Converters bridge the gap between physical world and digital signal processing. Most times analog signals received from the real world needs to be amplified and converted to digital to impart various signal enhancements to the received signal. The digital signal is much suitable to operate on with less noise and well defined logic levels when compared to continuously varying analog signal. Communication systems demand ever-increasing bandwidth which unfortunately has been a huge limitation for present day ADCs. Hence, an architecture which combines the accuracy of a SAR -ADC with the concept of pipelining to increase the bandwidth …

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Detection Of Ddos Attacks Against The Sdn Controller Using Statistical Approaches, Basheer Husham Ali Al-Mafrachi Jan 2017

Detection Of Ddos Attacks Against The Sdn Controller Using Statistical Approaches, Basheer Husham Ali Al-Mafrachi

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In traditional networks, switches and routers are very expensive, complex, and inflexible because forwarding and handling of packets are in the same device. However, Software Defined Networking (SDN) makes networks design more flexible, cheaper, and programmable because it separates the control plane from the data plane. SDN gives administrators of networks more flexibility to handle the whole network by using one device which is the controller. Unfortunately, SDN faces a lot of security problems that may severely affect the network operations if not properly addressed. Threat vectors may target main components of SDN such as the control plane, the data …

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Gait Analysis From Wearable Devices Using Image And Signal Processing, Bradley A. Schneider Jan 2017

Gait Analysis From Wearable Devices Using Image And Signal Processing, Bradley A. Schneider

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We present the results of analyzing gait motion in-person video taken from a commercially available wearable camera embedded in a pair of glasses. The video is analyzed with three different computer vision methods to extract motion vectors from different gait sequences from four individuals for comparison against a manually annotated ground truth dataset. Using a combination of signal processing and computer vision techniques, gait features are extracted to identify the walking pace of the individual wearing the camera and are validated using the ground truth dataset. We perform an additional data collection with both the camera and a body-worn accelerometer …

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Web-Delivered Assembly Language Interactive Training And Its Sequence Identification For Software Reverse Engineering, Sunethra Thimmapuram Jan 2017

Web-Delivered Assembly Language Interactive Training And Its Sequence Identification For Software Reverse Engineering, Sunethra Thimmapuram

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The purpose of this research is to help the beginners of software reverse engineering, the process of extracting knowledge or design information from a product and reproducing it on basis of extracted information. Beginner users often find it difficult to use, as the task may be found daunting at first sight due to a lack of existing learning resources. We need a better way to present information to the novice reverse engineer about how to understand low-level sequences of assembly instructions. This is akin to how the key to learning a foreign language is based upon a fundamental knowledge of …

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Sv-Means: A Fast One-Class Support Vector Machine-Based Level Set Estimator, Anne M. Pavy Jan 2017

Sv-Means: A Fast One-Class Support Vector Machine-Based Level Set Estimator, Anne M. Pavy

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In this dissertation, a novel algorithm, SV-Means, is developed motivated by the many functions needed to perform radar waveform classification in an evolving, contested environment. Important functions include the ability to: reject classes not in the library, provide confidence in the classification decision, adapt the decision boundary on-the-fly, discover new classes, and quickly add new classes to the library. The SV-Means approach addresses these functions by providing a fast algorithm that can be used for anomaly detection, density estimation, open set classification, and clustering, within a Bayesian generative framework. The SV-Means algorithm extends the quantile one-class support vector machine (q-OCSVM) …

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Semi-Supervised Approach To Monitoring Clinical Depressive Symptoms In Social Media, Amir Hossein Yazdavar, Hussein S. Al-Olimat, Monireh Ebrahimi, Goonmeet Bajaj, Tanvi Banerjee, Krishnaprasad Thirunarayan, Jyotishman Pathak, Amit Sheth Jan 2017

Semi-Supervised Approach To Monitoring Clinical Depressive Symptoms In Social Media, Amir Hossein Yazdavar, Hussein S. Al-Olimat, Monireh Ebrahimi, Goonmeet Bajaj, Tanvi Banerjee, Krishnaprasad Thirunarayan, Jyotishman Pathak, Amit Sheth

Computer Science and Engineering Faculty Publications

With the rise of social media, millions of people are routinely expressing their moods, feelings, and daily struggles with mental health issues on social media platforms like Twitter. Unlike traditional observational cohort studies conducted through questionnaires and self-reported surveys, we explore the reliable detection of clinical depression from tweets obtained unobtrusively. Based on the analysis of tweets crawled from users with self-reported depressive symptoms in their Twitter profiles, we demonstrate the potential for detecting clinical depression symptoms which emulate the PHQ-9 questionnaire clinicians use today. Our study uses a semi-supervised statistical model to evaluate how the duration of these symptoms …

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An Optimization Strategy For Hexapod Gait Transition, Naga Harika Darbha Jan 2017

An Optimization Strategy For Hexapod Gait Transition, Naga Harika Darbha

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Legged robots often need to move through different terrains as they function. This requires a change of gaits by the robot in order to move with better efficiency. There has been a lot of research done to find out which gait works better for a given terrain so that the robot can change its gait accordingly. A reliable analysis of when exactly should the transition take place in a walking robot is important, so that there can be an assurance of stability in the locomotion of the robot during the transition between different gaits. This work presents analysis performed on …

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Context-Dependence Of Physiological Systems: Environment-Physiology Interactions In The Respiratory Control System, Joseph M. Santin Jan 2017

Context-Dependence Of Physiological Systems: Environment-Physiology Interactions In The Respiratory Control System, Joseph M. Santin

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We know that animals are tuned to survive different environmental conditions or else life would not exist. Unfortunately, this is often forgotten or ignored when designing experiments. As Marsh Tenney articulated, "The physiologist keeps the whole always in mind. He accepts the tactical necessity of reductionism to understand parts, but, once done, for him it is only the beginning, never the end” (from Remmers, 2005). In an era when it is all too common to take environmental complexity out of the organism to understand physiology, my work puts some of that complexity back in the study of organisms. I take …

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Visualization Of Carbon Monoxide Particles Released From Firearms, Sadan Suneesh Menon Jan 2017

Visualization Of Carbon Monoxide Particles Released From Firearms, Sadan Suneesh Menon

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A number of soldiers have come forward to report discomfort, irritation and respiratory problems after taking part in a live firing session. These problems are caused due to the fumes and particulates emitted from the gun upon firing. There exists substantial research work focused on lead and other harmful metallic particulates expelled from a firearm, since they are the most harmful among the other emissions. However, our research focuses on visualizing the carbon monoxide (CO) particles released from a firearm in order to help understand adverse effects they may have on the human body. We use data provided by researchers …

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Design Of A Programmable Four-Preset Guitar Pedal, Michael Trombley Jan 2017

Design Of A Programmable Four-Preset Guitar Pedal, Michael Trombley

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Many companies in the music industry offer programmable preset guitar pedals. Presets allow musicians to save time and focus on their act by recalling predetermined settings during a performance. A majority of the companies in the music industry offer up to hundreds of presets, but realistically the substantial amount of presets may have a negative effect on the musician’s performance due to time constraints. The main contribution of this thesis is to address the musician by reducing the amount of presets offered in a guitar pedal design. Combining two systems, a digital control and audio processing circuit, will produce a …

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Defect Engineering: A Path Toward Exceeding Perfection, Hamed Attariani, Kasra Momeni, Kyle R. Adkins Jan 2017

Defect Engineering: A Path Toward Exceeding Perfection, Hamed Attariani, Kasra Momeni, Kyle R. Adkins

Mechanical and Materials Engineering Faculty Publications

Moving to nanoscale is a path to get perfect materials with superior properties. Yet defects, such as stacking faults (SFs), are still forming during the synthesis of nanomaterials and, according to common notion, degrade the properties. Here, we demonstrate the possibility of engineering defects to, surprisingly, achieve mechanical properties beyond those of the corresponding perfect structures. We show that introducing SFs with high density increases the Young’s Modulus and the critical stress under compressive loading of the nanowires above those of a perfect structure. The physics can be explained by the increase in intrinsic strain due to the presence of …

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Four-Terminal Square Piezoresistive Sensors For Mems Pressure Sensing, Awlad Hossain, Ahsan Mian Jan 2017

Four-Terminal Square Piezoresistive Sensors For Mems Pressure Sensing, Awlad Hossain, Ahsan Mian

Mechanical and Materials Engineering Faculty Publications

The sensitivity of four-terminal piezoresistive sensors commonly referred to as van der Pauw (VDP) structure is investigated. The VDP sensor is considered to be fabricated on (100) silicon due to its potential application in MEMS (microelectromechanical systems) pressure sensors. The sensitivity of the VDP sensor may be affected by misalignment during the etching/diffusion process, the nonuniformity of piezoresistive coefficients through the sensor thickness, and pad size with respect to the sensor size. For this particular analysis, the effect of VDP stress sensitivity on variations in pad sizes and through-the-thickness -coefficient variation are studied as the effect of misalignment has already …

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Computational Modeling Of A Williams Cross Flow Turbine, Sajjan Pokhrel Jan 2017

Computational Modeling Of A Williams Cross Flow Turbine, Sajjan Pokhrel

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Hydropower is not only the most used renewable energy source in the United States, but in the world. While it is well known that large hydropower facilities, like the Hoover Dam, provide large amounts of electrical power, there is also a tremendous opportunity for hydroelectric power generation from small scale facilities that has largely been overlooked. The work being presented here studies a new cross flow turbine called the Williams Cross Flow Turbine (WCFT), which was designed to extract electric energy from low head, run-of-the-river, small hydropower sites. To spur the implementation of the WCFT in small hydropower applications, and …

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An Industrial Vision System To Analyze The Wear Of Cutting Tools, Christina Gillmann, Tobias Post, Benjamin Kirsch, Thomas Wischgoll, Jörg Hartig, Bernd Hamann, Hans Hagen, Jan C. Aurich Jan 2017

An Industrial Vision System To Analyze The Wear Of Cutting Tools, Christina Gillmann, Tobias Post, Benjamin Kirsch, Thomas Wischgoll, Jörg Hartig, Bernd Hamann, Hans Hagen, Jan C. Aurich

Computer Science and Engineering Faculty Publications

The wear behavior of cutting tools directly affects the quality of the machined part. The measurement and evaluation of wear is a time consuming process and is subjective. Therefore, an image-based wear measurement that can be computed automatically based on given image series of cutting tools and an objective way to review the resulting wear is presented in this paper. The presented method follows the industrial vision system pipeline where images of cutting tools are used as input which are then transformed through suitable image processing methods to prepare them for the computation of a novel image based wear measurement. …

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Panel: Teaching To Increase Diversity And Equity In Stem, Helen H. Hu, Douglas Blank, Albert Chan, Travis E. Doom Jan 2017

Panel: Teaching To Increase Diversity And Equity In Stem, Helen H. Hu, Douglas Blank, Albert Chan, Travis E. Doom

Computer Science and Engineering Faculty Publications

TIDES (Teaching to Increase Diversity and Equity in STEM) is a three-year initiative to transform colleges and universities by changing what STEM faculty, especially CS instructors, are doing in the classroom to encourage the success of their students, particularly those that have been traditionally underrepresented in computer science.Each of the twenty projects selected proposed new inter-disciplinary curricula and adopted culturally sensitive pedagogies, with an eye towards departmental and institutional change. The four panelists will each speak about their TIDES projects, which all involved educating faculty about cultural competency. Three of the panelists infused introductory CS courses with applications from other …

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Probabilistic Analysis Of Wear Of Polymer Material Used In Medical Implants, V. Perel, Tarun Goswami Jan 2017

Probabilistic Analysis Of Wear Of Polymer Material Used In Medical Implants, V. Perel, Tarun Goswami

Biomedical, Industrial & Human Factors Engineering Faculty Publications

Probabilistic methods are applied to the study of fatigue wear of sliding surfaces. A variance of time to failure (to occurrence of maximum allowable wear depth) is evaluated as a function of a mean wear rate of normal wear and a size of wear particles. A method of estimating probability of failure-free work during a certain time interval (reliability) is presented. An effect of the bedding-in phase of wear on the reliability is taken into account. Experimental data for Ultra High Molecular Weight Polyethylene (UHMWPE) cups of artificial hip implants is used to make numerical calculations.

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Engineering Inpatient Discharges: Disposition Prediction And Day-Of-Discharge Planning, Nicholas A. Ballester Jan 2017

Engineering Inpatient Discharges: Disposition Prediction And Day-Of-Discharge Planning, Nicholas A. Ballester

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Inpatient discharge planning is a critical decision point in patient care, with implications for the efficiency of the inpatient unit as well as other units of the acute care hospital. Inefficient discharge planning can cause patient boarding (waiting for beds) in the upstream units. While this is a poignant and well-known problem in healthcare, very little quantitative research exists that proposes approaches to alleviate it. To address this issue, we apply Systems Engineering methods with focus on three key challenges in inpatient discharge planning. First, to aid inpatient care providers in predicting discharge disposition (home vs. non-home) within 24-hours of …

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Development Of Computer Program For Wind Resource Assessment, Rotor Design And Rotor Performance, Valentina Jami Jan 2017

Development Of Computer Program For Wind Resource Assessment, Rotor Design And Rotor Performance, Valentina Jami

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People understand and have seen that renewable energy has many advantages over conventional energy sources. Because of these advantages, more and more emphasis has been given to generating electrical energy with renewable sources. Among the many renewable and conventional ways currently available for a society to generate electrical power, wind turbines are one of the cheapest ways of doing this. The main objective of this thesis work is to develop a computer program that assesses the wind resource at a given location, designs a wind turbine rotor for optimum power capture for one wind speed, and analyzes the performance of …

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Development Of Guidance Laws For A Reduced Order Dynamic Aircraft Model, Jack W. Brendlinger Jan 2017

Development Of Guidance Laws For A Reduced Order Dynamic Aircraft Model, Jack W. Brendlinger

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A set of guidance control laws has been developed for enabling three distinct modes of operation of a reduced order dynamic aircraft model. These include 1) a waypoint following control law, 2) a trajectory tracking control law, and 3) a set of kinematically constrained control laws for reaching a commanded altitude, speed or heading. The formulation of the reduced order model is presented so that the capabilities and limitations of the model are understood, and so that the interface architecture between the controllers and the plant is clearly defined. The controller formulations are then presented, together with sample results. The …

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A High-Dimensional Data Quality Metric Using Pareto Optimality, Tobias Post, Thomas Wischgoll, Bernd Hamann, Hans Hagen Jan 2017

A High-Dimensional Data Quality Metric Using Pareto Optimality, Tobias Post, Thomas Wischgoll, Bernd Hamann, Hans Hagen

Computer Science and Engineering Faculty Publications

The representation of data quality within established high-dimensional data visualization techniques such as scatterplots and parallel coordinates is still an open problem. This work offers a scale-invariant measure based on Pareto optimality that is able to indicate the quality of data points with respect to the Pareto front. In cases where datasets contain noise or parameters that cannot easily be expressed or evaluated mathematically, the presented measure provides a visual encoding of the environment of a Pareto front to enable an enhanced visual inspection.

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Smart Ev Charging For Improved Sustainable Mobility, Ashutosh Shivakumar Jan 2017

Smart Ev Charging For Improved Sustainable Mobility, Ashutosh Shivakumar

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The landscape of energy generation and utilization is witnessing an unprecedented change. We are at the threshold of a major shift in electricity generation from utilization of conventional sources of energy like coal to sustainable and renewable sources of energy like solar and wind. On the other hand, electricity consumption, especially in the field of transportation, due to advancements in the field of battery research and exponential technologies like vehicle telematics, is seeing a shift from carbon based to Lithium based fuel. Encouraged by 1. Decrease in the cost of Li – ion based batteries 2. Breakthroughs in battery chemistry …

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Diffusion Maps And Transfer Subspace Learning, Olga L. Mendoza-Schrock Jan 2017

Diffusion Maps And Transfer Subspace Learning, Olga L. Mendoza-Schrock

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Transfer Subspace Learning has recently gained popularity for its ability to perform cross-dataset and cross-domain object recognition. The ability to leverage existing data without the need for additional data collections is attractive for Aided Target Recognition applications. For Aided Target Recognition (or object assessment) applications, Transfer Subspace Learning is particularly useful, as it enables the incorporation of sparse and dynamically collected data into existing systems that utilize large databases. In this dissertation, Manifold Learning and Transfer Subspace Learning are combined to create new Aided Target Recognition systems capable of achieving high target recognition rates for cross-dataset conditions and cross-domain applications. …

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Processing Of Ultra-Thin Film Of Un Modified C60 Fullerene Using The Langmuir-Blodgett Technique. Effect Of Structure On Stiffness And Optoelectric Properties, Hasanain Basim Altalebi Jan 2017

Processing Of Ultra-Thin Film Of Un Modified C60 Fullerene Using The Langmuir-Blodgett Technique. Effect Of Structure On Stiffness And Optoelectric Properties, Hasanain Basim Altalebi

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Monolayer films of C60 fullerene were for the first time produced successfully by using the Langmuir-Blodgett technique. The processing parameters were optimized and the structure of these films has been investigated using Scanning Tunneling Microscopy (STM) and Atomic Force Microscopy (AFM). Film stiffness was measured to be in the range of 15 MPa to 32 MPa depending on the nature of the solvent used to process the films. Optical transparency and electrical performance have been measured and correlated to the film structure. While 100% transparent, the film measured conductivity was in the range of 1013 S/m, that is orders of …

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Optimal Feature Selection For Spatial Histogram Classifiers, Mandira Thapa Jan 2017

Optimal Feature Selection For Spatial Histogram Classifiers, Mandira Thapa

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Point set classification methods are used to identify targets described by a spatial collection of points, each represented by a set of attributes. Relative to traditional classification methods based on fixed and ordered feature vectors, point set methods require additional robustness to obscured and missing features, thus necessitating a complex correspondence process between testing and training data. The correspondence problem is efficiently solved via spatial pyramid histograms and associated matching algorithms, however the storage requirements and classification complexity grow linearly with the number of training data points. In this thesis, we develop optimal methods of identifying salient point-features that are …

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An Experimental Investigation Of Residual Stress Development During Selective Laser Melting Of Ti-6al-4v, Nathan Charles Levkulich Jan 2017

An Experimental Investigation Of Residual Stress Development During Selective Laser Melting Of Ti-6al-4v, Nathan Charles Levkulich

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Selective laser melting (SLM) is an additive manufacturing (AM) process that gives rise to large thermal gradients and rapid cooling rates that lead to the development of undesirable residual stress and distortion. In this work, a number of different techniques (i.e., x-ray-diffraction, hole-drilling, layer-removal, and contour) were utilized to establish the effect of process parameters on residual stress development during SLM of Ti-6Al-4V. The measurements indicated that higher laser power, slower scan speed, smaller stripe width, reduced substrate overhang, and reduced build plan area each reduce the level of residual stress. In addition, the correlation between microstructure, crystallographic texture, and …

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