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

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

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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 …


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 said …


Fabrication And Characterizations Of Lithium Aluminum Titanate Phosphate Solid Electrolytes For Li-Based Batteries, Anurag Yaddanapudi Jan 2018

Fabrication And Characterizations Of Lithium Aluminum Titanate Phosphate Solid Electrolytes For Li-Based Batteries, Anurag Yaddanapudi

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Demands for electric vehicles and flexible electronics have escalated research in developing high-performance lithium batteries based on solid-state chemistry. The present work is to develop highly-conductive and flexible solid electrolyte for such applications. Lithium aluminum titanate phosphate (LATP or Li1.3Al0.3Ti1.7(PO4)3), both in ceramic pellets and free-standing composite membranes, have been fabricated. The crystal structure, surface morphology, and ionic conductivity are systematically studied. LATP pellets are prepared using solid state reaction approach. The results indicate that calcine temperature has significant impacts on the phase impurity and sintering temperature and duration have more impacts on the grain size and porosity of LATP …


Implementation Of Unmanned Aerial Vehicles Reporting Plume Cloud Concentration Values In A 3d Simulation Environment, Emily Catherine Novak Jan 2018

Implementation Of Unmanned Aerial Vehicles Reporting Plume Cloud Concentration Values In A 3d Simulation Environment, Emily Catherine Novak

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Unmanned aerial vehicles, or UAVs, have the potential to vastly improve plume cloud tracking at low cost. Plume clouds can be produced from blast mining, chemical warfare, unintended man-made disasters, and natural causes. This thesis provides implementation of the capability to simulate a 3D environment in which UAVs are individually controlled and each report a plume's concentration value at a specific location. It leverages existing industry standard technologies, including the PX4 autopilot system, the Gazebo simulation environment, the Robot Operating System (ROS), and QGroundControl. The provided system integrates the existing tools with a plume model plug-in that provides simulated plume …


A Framework To Understand Emoji Meaning: Similarity And Sense Disambiguation Of Emoji Using Emojinet, Sanjaya Wijeratne Jan 2018

A Framework To Understand Emoji Meaning: Similarity And Sense Disambiguation Of Emoji Using Emojinet, Sanjaya Wijeratne

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Pictographs, commonly referred to as `emoji’, have become a popular way to enhance electronic communications. They are an important component of the language used in social media. With their introduction in the late 1990’s, emoji have been widely used to enhance the sentiment, emotion, and sarcasm expressed in social media messages. They are equally popular across many social media sites including Facebook, Instagram, and Twitter. In 2015, Instagram reported that nearly half of the photo comments posted on Instagram contain emoji, and in the same year, Twitter reported that the `face with tears of joy’ emoji has been tweeted 6.6 …


Novel Auto-Calibrating Neural Motor Decoder For Robust Prosthetic Control, Andrew Earl Montgomery Jan 2018

Novel Auto-Calibrating Neural Motor Decoder For Robust Prosthetic Control, Andrew Earl Montgomery

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The overarching goal of this project is to develop novel neural motor decoders for prosthetic control. EMG decoders measure the activity from an intact but non-target muscle. Neural motor decoders transform the signal measured from the severed motor axons of the target muscle. A multi-scale, highly-realistic computer model of a spinal motor pool was developed (Allen & Elbasiouny, 2018) to serve as a computational platform for decoder development and testing. A firing rate-based algorithm was developed to transform the aggregate discharge of the motor pool into a command signal to control the simulated prosthetic MuJoCo hand. This algorithm was informed …


A Multi-Formal Languages Collaborative Scheme For Complex Human Activity Recognition And Behavioral Patterns Extraction, Anargyros Angeleas Jan 2018

A Multi-Formal Languages Collaborative Scheme For Complex Human Activity Recognition And Behavioral Patterns Extraction, Anargyros Angeleas

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Human Activity Recognition is an actively researched domain for the past few decades, and is one of the most eminent applications of today. It is already part of our life, but due to high level of uncertainty and challenges of human detection, we have only application specific solutions. Thus, the problem being very demanding and still remains unsolved. Within this PhD we delve into the problem, and approach it from a variety of viewpoints. At start, we present and evaluate different architectures and frameworks for activity recognition. Henceforward, the focal point of our attention is automatic human activity recognition. We …


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

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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, …


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

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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 precautions …


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

Evaluation Of Consumer Drone Control Interface, Thomas William Merrell

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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 …


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

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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 …


Virtual Doctor: An Intelligent Human-Computer Dialogue System For Quick Response To People In Need, Stavros Mallios Jan 2018

Virtual Doctor: An Intelligent Human-Computer Dialogue System For Quick Response To People In Need, Stavros Mallios

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One of the challenges of our society is the existence of chronic-related conditions and diseases among the elderly and people at risk. Apart from the welfare of people, a significant impact of this phenomenon is the accumulation of high financial costs for both individuals and health care systems. In order to address this issue and to reduce its effects, many efforts have been made towards preventing, identifying in early stages and, generally, managing chronic-related medical conditions and diseases. As a result, there has been a keen research and market interest in health monitoring devices during the past few decades. Nevertheless, …


Malware Analysis Skills Taught In University Courses, Swetha Gorugantu Jan 2018

Malware Analysis Skills Taught In University Courses, Swetha Gorugantu

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Career opportunities for malware analysts are growing at a fast pace due to the evolving nature of cyber threats as well as the necessity to counter them. However, employers are often unable to hire analysts fast though due to a lack of the required skillset. Hence, the primary purpose of the thesis is to conduct a gap analysis between the binary analysis skills taught in universities with those that the recruiters are looking for. Malware can be analyzed using three main types of tools and techniques: high-level profiling, static analysis, and dynamic analysis. These methods provide detailed information about the …


Sensor Data Streams Correlation Platform For Asthma Management, Vaikunth Sridharan Jan 2018

Sensor Data Streams Correlation Platform For Asthma Management, Vaikunth Sridharan

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Asthma is a high-burden chronic inflammatory disease with prevalence in children with twice the rate compared to adults. It can be improved by continuously monitoring patients and their environment using the Internet of Things (IoT) based devices. These sensor data streams so obtained are essential to comprehend multiple factors triggering asthma symptoms. In order to support physicians in exploring causal associations and finding actionable insights, a visualization system with a scalable cloud infrastructure that can process multimodal sensor data and Patient Generated Health Data (PGHD) is necessary. In this thesis, we describe a cloud-based asthma management and visualization platform that …


Development And Thermal Management Of A Dynamically Efficient, Transient High Energy Pulse System Model, Nathaniel J. Butt Jan 2018

Development And Thermal Management Of A Dynamically Efficient, Transient High Energy Pulse System Model, Nathaniel J. Butt

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As technology advances, the abilities of civilian and military vehicles, both air and ground, will undoubtedly increase as well. One of the main areas of improvement is in the electronics area. The new electronics are ever smaller, use ever higher amounts of electrical power, and require ever smaller temperature tolerances. This leads to the problem of effectively managing the increasing thermal loads and temperature tolerances on these systems. One electronic system that causes concern is a high energy pulse system (HEPS). These devices have very high thermal loads (100s of kW). On an air vehicle, where thermal management by legacy …


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

Slim Embedding Layers For Recurrent Neural Language Models, Zhongliang Li

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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 …


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

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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 …


Design Optimization Of A Non-Axisymmetric Endwall Contour For A High-Lift Low Pressure Turbine Blade, Jacob Allen Dickel Jan 2018

Design Optimization Of A Non-Axisymmetric Endwall Contour For A High-Lift Low Pressure Turbine Blade, Jacob Allen Dickel

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Various approaches have been used to shape the geometry at the junction of the endwall and the blade profile in high-lift low-pressure turbine passages in order to reduce the endwall losses. This thesis will detail the workflow to produce an optimized non-axisymmetric endwall contour design for a front-loaded high-lift research turbine profile. Validation of the workflow was performed and included a baseline planar and test contour case for a future optimization study. Endwall contours were defined using a series of Bezier curves across the passage to create a smooth surface. A parametric based approach was used to develop the test …


Control And Optimization Of Power In Llc Converter Using Phase Control, Nagasri Kollipara Jan 2018

Control And Optimization Of Power In Llc Converter Using Phase Control, Nagasri Kollipara

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LLC resonant converters are popular among resonant topologies due to their high efficiency and ability to achieve ZVS and ZCS for wide input range. LLC resonant converters are controlled by frequency modulation (FM), which makes converter difficult to optimize the system in terms of achieving efficient power conversion. FM technique also generate wide range of harmonics which leads to a wide sweep in operating frequency, which can run into regulatory EMI test limits and cause electromagnetic compatibility issues. The performance of LLC topology extends to their poor efficiency at lighter loads, due to constant high magnetization current. In order to …


Functionalization And Characterization Of Chemical Vapor Deposited Graphene Sheets Towards Application In Chemical Vapor Sensing, Nicholas Alexander Engel Jan 2018

Functionalization And Characterization Of Chemical Vapor Deposited Graphene Sheets Towards Application In Chemical Vapor Sensing, Nicholas Alexander Engel

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Chemical/biological sensors serve many purposes in protecting machinery, the environment, and human life/wellness. Graphene, a two-dimensional (2-D) material made up of carbon atoms in a honeycomb-like lattice, is promising for applications to chemical/biological sensing due to its unique properties. Functionalization of graphene by surface decorating with nanoparticles and increasing interior adsorption sites can tailor its catalytic activity and electrical properties, and hence, important for detecting and distinguishing trace hazardous gases. This research introduces two different approaches to functionalize graphene towards enhanced sensitivity and selectivity of graphene-based sensors. The morphologies, structures, and electrical properties of the functionalized graphene are systematically characterized. …


The Feasibility Of Dementia Caregiver Task Performance Measurement Using Smart Gaming Technology, Garrett G. Goodman Jan 2018

The Feasibility Of Dementia Caregiver Task Performance Measurement Using Smart Gaming Technology, Garrett G. Goodman

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Dementia caregiver burnout is detrimental to both the familial caregiver and their loved ones with dementia. As the population of older adults increases, both the number of individuals with dementia and their corresponding caregivers increase as well. Thus, we are interested in developing a potential tool to non-invasively detect signs of caregiver burnout using a mobile application combined with machine learning. Hence, the mobile application "Caregiver Assessment using Smart Technology" (CAST) was developed which personalizes a word scramble game. The CAST application utilizes a heuristically constructed Fuzzy Inference System (FIS) optimized via a Genetic Algorithm (GA) to provide an individualized …


Feed-Forward Compensation Of Non-Minimum Phase Systems, Venkatesh Dudiki Jan 2018

Feed-Forward Compensation Of Non-Minimum Phase Systems, Venkatesh Dudiki

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Due to inherent limitations posed by existence of zeros of a transfer function in the righthalfof the complex plane, known as non-minimum phase zeros, the issue of dealing withsuch zeros is extremely important in control of linear systems. Considerable literatureexists in control theory to try and minimize or eliminate the effect of non-minimum phasezeros. These include pole-zero cancellation, feedforward compensation, among others.These methods are only limited only to stable systems (systems with poles in the left halfof the complex plane); and will fail for systems that are unstable as well as non-minimumphase.This research focuses in designing feedforward compensators for unstable …


Switching Neural Network Systems For Nonlinear Tracking, Manoj Ghimire Jan 2018

Switching Neural Network Systems For Nonlinear Tracking, Manoj Ghimire

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In this thesis, we consider the problem of tracking in complex nonlinear dynamical systems. While the Kalman filter is known to be the mean-squared error optimal tracker under linear dynamics and linear measurements, more sophisticated models and algorithms are required for complex dynamics. Here, we consider switching systems where the dynamical properties vary (''switch modes") over time. For example, the dynamics of a vehicle may switch as it transitions from interstate to urban conditions, human speech dynamics switch as speakers change, and stock market dynamics switch with discrete news events. In this work, we use mode-dependent neural networks to capture …


Fully Transparent Computer Vision Framework For Ship Detection And Tracking In Satellite Imagery, Jason T. Gottweis Jan 2018

Fully Transparent Computer Vision Framework For Ship Detection And Tracking In Satellite Imagery, Jason T. Gottweis

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Tracking of ships in satellite imagery is a challenging problem in remote sensing since it requires both object detection and object recognition. Most of the resources available only cover one of these problems and are often filled with machine learning techniques which are costly to train. Additionally, the techniques covered in these resources are often difficult to replicate or may be hard to combine with other solutions to get a full tracking algorithm. The proposed framework offers a transparent and efficient alternative to machine learning approaches and includes preprocessing, detection, and recognition needed for tracking. All components of the framework …


Temperature Robust Longwave Infrared Hyperspectral Change Detection, Nicholas A. Durkee Jan 2018

Temperature Robust Longwave Infrared Hyperspectral Change Detection, Nicholas A. Durkee

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In this thesis, we develop and evaluate change detection algorithms for longwave infrared (LWIR) hyperspectral imagery. Because measured radiance in the LWIR domain depends on unknown surface temperature, care must be taken to prevent false alarms resulting from in-scene temperature differences that appear as material changes. We consider fewer variables. Examples using synthetic and measured data quantify the computational complexity of the proposed methods and demonstrate orders of magnitude reduction in false alarm rates relative to existing methods. Four strategies to mitigate this effect. In the first, pre-processing via traditional temperatureemissivity separation yields approximately temperature-invariant emissivity vectors for use in …


Wideband Doa And Parameter Estimation Of Chirp Sources Using Dcft And Compressive Sensing, Luay A. Al Irkhis Jan 2018

Wideband Doa And Parameter Estimation Of Chirp Sources Using Dcft And Compressive Sensing, Luay A. Al Irkhis

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Direction of Arrival (DoA) estimation of chirp sources has many applications in radar, sonar and medical imaging. This work considers DoA and parameter estimation of wide- band chirp sources by the use of Discrete Chirp Fourier Transform (DCFT), its Compres- sive Sensing formulation (CS-DCFT) and Distributed CS. DCFT is similar to traditional Discrete Fourier Transform (DFT) but with chirp ba- sis and two-dimensional search over chirp rate and chirp frequency. For chirp parame- ters estimation, the proposed Compressive Sensing (CS) formulation uses the parametric DCFT basis to achieve superior estimator performance in polynomial time using Orthog- onal Matching Pursuit (OMP) …


Exploring Feedback Modalities Using Wearable Device For Complex Systems Training Programs, Layla Akilan Jan 2018

Exploring Feedback Modalities Using Wearable Device For Complex Systems Training Programs, Layla Akilan

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This study examined the effectiveness of a wearable device in delivering various feedback modalities in an attempt to improve performance outcomes in complex systems. Secondarily this study looked at performance when feedback type was matched to preferred learning style according to VARK Learning Styles Inventory results. Participants were required to perform system monitoring and correct for system failures through key presses. Feedback was delivered through a smart watch and was based on response time performance. Feedback modalities included visual, auditory, and haptic feedback. Subjective ratings of situation awareness and mental workload were also examined. Results indicated that auditory feedback condition …


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 to …


Use Of Adaptive Mobile Applications To Improve Mindfulness, Wiehan Boshoff Jan 2018

Use Of Adaptive Mobile Applications To Improve Mindfulness, Wiehan Boshoff

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Mindfulness is the state of retaining awareness of what is happening at the current point in time. It has been used in multiple forms to reduce stress, anxiety, and even depression. Promoting Mindfulness can be done in various ways, but current research shows a trend towards preferential usage of breathing exercises over other methods to reach a mindful state. Studies have showcased that breathing can be used as a tool to promote brain control, specifically in the auditory cortex region. Research pertaining to disorders such as Tinnitus, the phantom awareness of sound, could potentially benefit from using these brain control …


Influence Of Fdm Build Parameters On Tensile And Compression Behaviors Of 3d Printed Polymer Lattice Structures, Sai Avinash Yadlapati Jan 2018

Influence Of Fdm Build Parameters On Tensile And Compression Behaviors Of 3d Printed Polymer Lattice Structures, Sai Avinash Yadlapati

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This research focuses on the compression and tensile behavior of three-dimensional printed polymer lattice structures with different printing parameters such as build orientation, infill density, and layer thickness. The body-centered cubic (BCC) lattice unit cell, which has been extensively investigated for energy absorption applications, is considered here to create compression and tensile specimens. Special test fixture was designed and developed to perform the tensile tests. The specimens were printed using Acrylonitrile Butadiene Styrene (ABS) polymer material on a Stratasys uPrint 3D printer. The printing parameters considered in this case are: (a) Three different build orientations (0, 45 and 90 degrees); …