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2018

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Articles 2581 - 2610 of 8951

Full-Text Articles in Engineering

A Comparative Study Of Contact Stress From Different Standards For Some Theoretical Straight Bevel Gear Pairs, Edward E. Osakue, Lucky Anetor Aug 2018

A Comparative Study Of Contact Stress From Different Standards For Some Theoretical Straight Bevel Gear Pairs, Edward E. Osakue, Lucky Anetor

Faculty Publications

ANSI/AGMA 2003-B97, ISO 10300 standards and a new contact stress model are used to estimate and compare contact stresses in some theoretical straight bevel gear pairs. The contact stress expressions in the different gear standards and new model are formatted to highlight the similarity and differences. The power range of 10 to 15,000 kW, backend modules of 2.5 to 25 mm and backend pitch velocities of 4.58 to 25.37 m/s are covered. The results indicate that the percentage differences between the new contact stress and AGMA models are in the range of 2.22% to 7.40%. These differences are small but …


Biofidelic Piezoresistive Sandwich Composites, Nengda Jiang Aug 2018

Biofidelic Piezoresistive Sandwich Composites, Nengda Jiang

Doctoral Dissertations and Master's Theses

Silicone based biofidelic surrogates are being used in many biomedical applications; e.g. to understand the body injury mechanisms, evaluate protective equipment like helmets and armors. Apart from matching the mechanical behavior of bodily tissues, there is an increasing requirement for these materials to be electrically conductive and piezoresistive to facilitate direct instrumentation. Carbon nanotubes (CNTs) are a possible filler to impart electrical conductivity and piezoresistivity to silicone biofidelic materials. A sandwich structure of silicone and CNT sheet, comprising two dielectric facesheets and a highly conductive core layer has added advantages of raising the dielectric permittivity and suppressing dielectric loss.

In …


Experimental And Numerical Investigation On The Bond Strength Of Self-Sensing Composite Joints, Shafique Ahmed, Thomas Schumacher, Jennifer Mcconnell, Erik T. Thostenson Aug 2018

Experimental And Numerical Investigation On The Bond Strength Of Self-Sensing Composite Joints, Shafique Ahmed, Thomas Schumacher, Jennifer Mcconnell, Erik T. Thostenson

Civil and Environmental Engineering Faculty Publications and Presentations

Laboratory experiments demonstrate that a novel carbon nanotube (CNT)-based sensing layer embedded in the bondline of an adhesively bonded structural joint can detect and monitor deformation and damage progression of the adhesive layer. In this study, experimental and numerical investigations were performed to identify any effect of an embedded CNT-based sensing layer on the bond strength of that joint. To evaluate the mechanical behavior of such a bondline configuration, two sets of single-lap specimens, with and without sensing layer, were prepared and tested to determine the bond strengths of the respective types. Two-dimensional digital image correlation (2D DIC) was utilized …


Time Evolution Of Ecog Network Connectivity In Patients With Refractory Epilepsy, Michael J. Selesko Aug 2018

Time Evolution Of Ecog Network Connectivity In Patients With Refractory Epilepsy, Michael J. Selesko

Masters Theses

Epilepsy is a common neurological disorder that causes recurrent, unprovoked seizures. Focal, refractory epilepsy is characterized by seizures that start in a specific area in the brain and do not respond to antiepileptic medication. This study was conducted to characterize the connectivity of the focal brain region where seizures originate, known as the epileptogenic zone. Connectivity was measured from electrocorticogram (ECoG) recordings, during seizure events, using information theoretic measures mutual information (MI) and (TE). MI is the amount of information shared between two discrete random variables. TE is the directed information transfer between two discrete random variables. MI provides information …


A Case Study On Application Of Fuzzy Logic Based Controller For Peak Load Shaving In A Typical Household's Per Day Electricity Consumption, Krishna P. Sharma Aug 2018

A Case Study On Application Of Fuzzy Logic Based Controller For Peak Load Shaving In A Typical Household's Per Day Electricity Consumption, Krishna P. Sharma

Masters Theses

The cost of electricity for consumers depends on the cost of generation, transmission, and distribution of power. The electrical load consumed by consumers per day is not constant throughout the day. The utilities must be capable of meeting the load demand, which means they must have enough electricity generation potential and necessary infrastructure. This cost is significant. However, the revenue they generate will only be for the actual use of electricity by the consumers. In general, the electrical power generation is done in stages, always generating a base load. As demand changes throughout the day, additional stages of power generation …


Identification Of The Seizure Onset Zone By Auto-Regressive Model Residual Modulation Applied To Intracranial Eeg And Its Correlation To Channels With High Preponderances Of Detected Hfos, Allison L. Rogutich Aug 2018

Identification Of The Seizure Onset Zone By Auto-Regressive Model Residual Modulation Applied To Intracranial Eeg And Its Correlation To Channels With High Preponderances Of Detected Hfos, Allison L. Rogutich

Masters Theses

The objective of this thesis was to examine the ability of the Autoregressive Model Residual Modulation (ARRm) method to identify the Seizure Onset Zone (SOZ) in intracranial electroencephalogram (iEEG) of patients with refractory epilepsy. Patients who have not become seizure free after multiple trials of antiepileptic drugs (AEDs) may seek treatment through epilepsy surgery. Cortical electrodes are implanted directly on the cerebral cortex, then iEEG is collected. A specialized neurologist reviews the iEEG, then in consultation with the neurosurgeon, the SOZ is determined and areas of the brain may be chosen for resection. The success rate of epilepsy surgery varies, …


Modeling Of Cold Compressor Pump Down Process, Kyle A. Dinger Aug 2018

Modeling Of Cold Compressor Pump Down Process, Kyle A. Dinger

Masters Theses

The Facility for Rare Isotope Beams (FRIB) will use a sub-atmospheric helium refrigeration process operating at 2 K (31 mbar) to support the superconducting radio frequency (SRF) Niobium structures (known as cavities), which are housed within ‘cryo-modules’. The cryomodules are large containers whose exterior forms a vacuum chamber that serves as a thermal shield. The cryo-modules, and the superconducting devices contained within, are used to accelerate charged particles. The accelerator at FRIB is comprised of three separate linear segments, separately or collectively, called a linear accelerator or ‘LINAC’. The helium used as the working fluid to cool the SRF Niobium …


Pnnl Dark Matter Bubble Chamber, Ryan Robinson Aug 2018

Pnnl Dark Matter Bubble Chamber, Ryan Robinson

STAR Program Research Presentations

The Pacific Northwest National Laboratory (PNNL) prototype bubble chamber is intended to address issues encountered with the current PICO dark matter search detectors and improve the functionality of future experimental designs. The PNNL bubble chamber accomplishes this with a simplified interface between the hydraulic pressure controls and the target vessel and altering the standard chamber design such that it can be easily exchanged and replaced with vessels of various sizes and materials for testing purposes. The chamber itself is a glass vessel which houses perfluorobutane and holds the target fluid above room temperature and atmospheric pressure. The target fluid becomes …


Finite-Time Anti-Synchronization Of Memristive Stochastic Bam Neural Networks With Probabilistic Time-Varying Delays, Manman Yuan, Weiping Wang, Xiong Luo, Linlin Liu, Wenbing Zhao Aug 2018

Finite-Time Anti-Synchronization Of Memristive Stochastic Bam Neural Networks With Probabilistic Time-Varying Delays, Manman Yuan, Weiping Wang, Xiong Luo, Linlin Liu, Wenbing Zhao

Electrical and Computer Engineering Faculty Publications

This paper investigates the drive-response finite-time anti-synchronization for memristive bidirectional associative memory neural networks (MBAMNNs). Firstly, a class of MBAMNNs with mixed probabilistic time-varying delays and stochastic perturbations is first formulated and analyzed in this paper. Secondly, an nonlinear control law is constructed and utilized to guarantee drive-response finite-time anti-synchronization of the neural networks. Thirdly, by employing some inequality technique and constructing an appropriate Lyapunov function, some anti-synchronization criteria are derived. Finally, a number simulation is provided to demonstrate the effectiveness of the proposed mechanism.


Methods And Metrics To Measure And Predict The Social Impact Of Engineered Products, Phillip Douglas Stevenson Aug 2018

Methods And Metrics To Measure And Predict The Social Impact Of Engineered Products, Phillip Douglas Stevenson

Theses and Dissertations

More than ever before, engineers are creating products for developing countries. One of the purposes of these products is to improve the consumer's quality of life. Currently, there is no established method of measuring the social impact of these types of products. As a result, engineers have used their own metrics to assess their product's impact, if at all. Some of the common metrics used include products sold and revenue, which measure the financial success of a product without recognizing the social successes or failures it might have. In this thesis I introduce a potential metric, the Product Impact Metric …


Efficient Incorporation Of Fatigue Damage Constraints In Wind Turbine Blade Optimization, Bryce Taylor Ingersoll Aug 2018

Efficient Incorporation Of Fatigue Damage Constraints In Wind Turbine Blade Optimization, Bryce Taylor Ingersoll

Theses and Dissertations

Improving the wind turbine blade design has a significant effect on the efficiency of the wind turbine. This is a challenging multi-disciplinary optimization problem. During the blade design process, the aerodynamic shapes, sizing of the structural members, and material composition must all be determined and optimized. Some previous blade design methods incorporate the wind turbine's static response with an added safety factor to account for neglected dynamic effects. Others incorporate the dynamic response, but in general is limited to a few design cases. By not fully incorporating the dynamic response of the wind turbine, the final turbine blade design is …


Developing Optimization Techniques For Logistical Tendering Using Reverse Combinatorial Auctions, Jennifer Kiser Aug 2018

Developing Optimization Techniques For Logistical Tendering Using Reverse Combinatorial Auctions, Jennifer Kiser

Electronic Theses and Dissertations

In business-to-business logistical sourcing events, companies regularly use a bidding process known as tendering in the procurement of transportation services from third-party providers. Usually in the form of an auction involving a single buyer and one or more sellers, the buyer must make decisions regarding with which suppliers to partner and how to distribute the transportation lanes and volume among its suppliers; this is equivalent to solving the optimization problem commonly referred to as the Winner Determination Problem. In order to take into account the complexities inherent to the procurement problem, such as considering a supplier’s network, economies of scope, …


Selecting The Most Effective Energy Modeling Tool Based On A Project Requirement, Sodiq Akande Aug 2018

Selecting The Most Effective Energy Modeling Tool Based On A Project Requirement, Sodiq Akande

Electronic Theses and Dissertations

Building energy usage can be derived and controlled by performing building energy modeling. BEM can be performed using numerous software tools such as DesignBuilder, OpenStudio, EnergyPlus etc. These modeling tools can be sorted into three different modeling categories: Black-box, Gray-box and White-box. It is important for a modeler to be able to quickly select the proper tool from the proper category to meet the need of the project. To validate the method of categorizing tools, the three models generated using tools from each category and the modeling outputs required were compared. Each model was designed to estimate the amount of …


Advancing The Open Modeling Interface (Openmi) For Integrated Water Resources Modeling, Caleb A. Buahin, Jeffery S. Horsburgh Aug 2018

Advancing The Open Modeling Interface (Openmi) For Integrated Water Resources Modeling, Caleb A. Buahin, Jeffery S. Horsburgh

Publications

The use of existing component-based modeling frameworks for integrated water resources modeling is currently hampered for some important use cases because they lack support for commonly used, topology-aware, spatiotemporal data structures. Additionally, existing frameworks are often accompanied by large software stacks with steep learning curves. Others lack specifications for deploying them on high performance, heterogeneous computing (HPC) infrastructure. This puts their use beyond the reach of many water resources modelers. In this paper, we describe new advances in component-based modeling using a framework called HydroCouple. This framework largely adopts the Open Modeling Interface (OpenMI) 2.0 interface definitions but demonstrates important …


Efficacy Of Smart Pv Inverter As A Strategic Mitigator Of Network Harmonic Resonance And A Suppressor Of Temporary Overvoltage Phenomenon In Distribution Systems, Shriram Srinivasarangan Rangarajan Aug 2018

Efficacy Of Smart Pv Inverter As A Strategic Mitigator Of Network Harmonic Resonance And A Suppressor Of Temporary Overvoltage Phenomenon In Distribution Systems, Shriram Srinivasarangan Rangarajan

All Dissertations

The research work explores the design of Smart PV inverters in terms of modelling and investigates the efficacy of a Smart PV inverter as a strategic mitigator of network harmonic resonance phenomenon and a suppressor of Temporary Overvoltage (TOV) in distribution systems. The new application and the control strategy of Smart PV inverters can also be extended to SmartPark-Plug in Electric Vehicles as the grid becomes smarter.

As the grid is becoming smarter, more challenges are encountered with the integration of PV plants in distribution systems. Smart PV inverters nowadays are equipped with specialized controllers for exchanging reactive power with …


Coupled Hydrological-Geotechnical Model For Determinine Bearing Capacity And Elastic Settlement Of Foundations, Vahidreza Mahmoudabadi Arani Aug 2018

Coupled Hydrological-Geotechnical Model For Determinine Bearing Capacity And Elastic Settlement Of Foundations, Vahidreza Mahmoudabadi Arani

All Dissertations

This dissertation presents a coupled hydrological-geotechnical framework to investigate the performance of shallow and deep foundations under hydrological events such as heavy rainfall and drought. The variation in performance of foundation, interface between the structure and ground surface, is caused by the uncertainties associated with not only the geotechnical parameters but also the hydrological parameters that include intensity and duration of hydrological events and water table depth. The impact of such hydrological events significantly alters the performance of foundations by changing the soil strength and stiffness parameters of subsurface soil which may lead to foundation failures. Such failures can cause …


Demonstrating The Pollutant Loading From Stormwater Discharge To The Lower Jordan River Using High-Frequency Data, Ryan Dupont, Jacob Richardson, D. Willey, Rosa A. Fernández Valasquez Aug 2018

Demonstrating The Pollutant Loading From Stormwater Discharge To The Lower Jordan River Using High-Frequency Data, Ryan Dupont, Jacob Richardson, D. Willey, Rosa A. Fernández Valasquez

Civil and Environmental Engineering Faculty Publications

Evaluate Stormwater Loading Above & Below Liberty Lake


Configuring Traditional Multi-Dock, Unit-Load Warehouses, Mahmut Tutam Aug 2018

Configuring Traditional Multi-Dock, Unit-Load Warehouses, Mahmut Tutam

Graduate Theses and Dissertations

The development of expected-distance formulas for multi-dock-door, unit-load warehouse configurations is the focus of the dissertation. From formulations derived, the width-to-depth ratios minimizing expected distances are obtained for rectangle-shaped, unit-load warehouse configurations. Partitioning the storage region in the warehouse into three classes, the performance of a multi-dock-door, unit-load warehouse is studied when storage regions can be either rectangle-shaped or contour-line-shaped. Our first contribution is the development of formulas for expected distance traveled in storing and retrieving unit loads in a rectangle-shaped warehouse having multiple dock doors along one warehouse wall and storage racks aligned perpendicular to that wall. Two formulations …


Modeling And Solution Approaches For Non-Traditional Network Flow Problems With Complicating Constraints, Negin Enayaty Ahangar Aug 2018

Modeling And Solution Approaches For Non-Traditional Network Flow Problems With Complicating Constraints, Negin Enayaty Ahangar

Graduate Theses and Dissertations

In this dissertation, we model three network-based optimization problems. Chapter 2 addresses the question of what the operation plan should be for interdependent infrastructure systems in resource-constrained environments so that they collectively operate at the highest level. We develop a network-based operation model of these systems that accounts for interdependencies among them. To solve this large-scale model, a solution approach is proposed that relatively quickly generates high-quality solutions to the problem.

Chapter 3 presents a routing model for a single train within a railyard with the objective of minimizing the total length traveled by train. The difference between this problem …


Analysis Of Flash In Injection Molding Using Flow Simulation And Design Of Experiments, Claudia Lizette Lopez Aug 2018

Analysis Of Flash In Injection Molding Using Flow Simulation And Design Of Experiments, Claudia Lizette Lopez

Theses and Dissertations

This study presents a method of detecting flash by using flow simulation along with the mold processing conditions and the DOE analysis values from all input and output parameters that will be calculated. All of this would be completed in order to compare and verify the DOE and simulation results and find out if it can be applied to an actual live production molded part, in this case, the Leap char ribbon. This paper will also describe the scrap issue that is presently happening on this molded part, and what are the options that there is in order to find …


Senior Computer Science Students’ Task And Revised Task Interpretation While Engaged In Programming Endeavor, Andreas Febrian Aug 2018

Senior Computer Science Students’ Task And Revised Task Interpretation While Engaged In Programming Endeavor, Andreas Febrian

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Developing a computer program is not an easy task. Studies reported that a large number of computer science students decided to change their major due to the extreme challenge in learning programming. Fortunately, studies also reported that learning various self-regulation strategies may help students to continue studying computer science. This study is interested in assessing students’ self-regulation, in specific their task understanding and its revision during programming endeavors. Task understanding is specifically selected because it affects the entire programming endeavor.

In this qualitative case study, two female and two male senior computer science students were voluntarily recruited as research participants. …


Determining The Effect Of Locally Delivered Bioactive Modulators On Macrophage Activation At The Implantation Site Of Different Biomaterials In Rats, Kamel Alkhatib Aug 2018

Determining The Effect Of Locally Delivered Bioactive Modulators On Macrophage Activation At The Implantation Site Of Different Biomaterials In Rats, Kamel Alkhatib

Graduate Theses and Dissertations

Altering the foreign body reaction by targeting macrophages has been of interest in the biomaterials field to improve the integration of longevity of implanted biomedical devices. The objective of this dissertation was to study the effect of locally delivered bioactive modulators on macrophage activation at the implantation site of different biomaterials in rats. Iloprost, a prostacyclin analog, was tested for its ability to direct macrophages to their pro-wound healing phenotype after the implantation of microdialysis probe in the subcutaneous space of male Sprague Dawley rats. This study showed that iloprost can shift macrophage activation states in vivo to the pro-wound …


Achieving Universal Liaisons And Healthcare Contact Center Centralization Through The Use Of Decision Support Tools, Jared S. Fiacco Aug 2018

Achieving Universal Liaisons And Healthcare Contact Center Centralization Through The Use Of Decision Support Tools, Jared S. Fiacco

Graduate Dissertations and Theses

Healthcare contact centers often experience a large volume of calls and traditional standardized guidelines can be difficult to follow during an active call. While more common workflows can be memorized, they change often because Healthcare is a dynamic field. Constant updates to workflows, an abundance of different processes and provider preferences, and a fast paced environment can lead Customer Service Liaisons (CSLs) to handle patient inquiries incorrectly. Active decision support tools enable a CSL to follow an updated workflow without needing to navigate through complex guidelines and emails. This research shows that contact center centralization through the use of decision …


Using Multifactor Inputs Bp Neural Network To Make Power Consumption Prediction, Hao Song Aug 2018

Using Multifactor Inputs Bp Neural Network To Make Power Consumption Prediction, Hao Song

Graduate Dissertations and Theses

With the development of modern information and technology (IT), smart grids became one of the major components of smart cities, to take full advantage of the smart grid, the capability of intelligent scheduling and planning of electricity delivery is essential. For this purpose, researchers have investigated methodologies for power consumption prediction and demand side management (DSM). In addition, conducting a comprehensive analysis and obtaining an accurate evaluation of power consumption are the premise and basis for a more robust and efficient power grid design and transformation. Therefore, it is meaningful to explore forecasting models that are able to reflect the …


New Era In Designing And Governing Cooling Intensity Of Liquid Quenchants To Decrease Distortion During Hardening Of Steel Parts, Nikolai I. Kobasko, Anatolii A. Moskalenko, P. N. Logvynenko, George E. Totten, Volodymyr V. Dobryvechir Aug 2018

New Era In Designing And Governing Cooling Intensity Of Liquid Quenchants To Decrease Distortion During Hardening Of Steel Parts, Nikolai I. Kobasko, Anatolii A. Moskalenko, P. N. Logvynenko, George E. Totten, Volodymyr V. Dobryvechir

Mechanical and Materials Engineering Faculty Publications and Presentations

It was proved in last decade that very intensive and uniform cooling eliminates quench crack formation and significantly decreases distortion of quenched steel parts as compared with their slow cooling in mineral oils. That opened a new era in design ing and governing cooling intensity of liquid quenchants for strengthening steel parts and decrease their distortion after quenching. The new approaches were developed by authors to provide accelerated and uniform cooling steel parts during quenching by creation on their surface thin insulating layers. For this purpose low concentration of water polymer solutions of inverse solubility are used as a quenchant. …


Evaluation Criteria For Selecting Nosql Databases In A Single Box Environment, Ryan D. Engle, Brent T. Langhals, Michael R. Grimaila, Douglas D. Hodson Aug 2018

Evaluation Criteria For Selecting Nosql Databases In A Single Box Environment, Ryan D. Engle, Brent T. Langhals, Michael R. Grimaila, Douglas D. Hodson

Faculty Publications

In recent years, NoSQL database systems have become increasingly popular, especially for big data, commercial applications. These systems were designed to overcome the scaling and flexibility limitations plaguing traditional relational database management systems (RDBMSs). Given NoSQL database systems have been typically implemented in large-scale distributed environments serving large numbers of simultaneous users across potentially thousands of geographically separated devices, little consideration has been given to evaluating their value within single-box environments. It is postulated some of the inherent traits of each NoSQL database type may be useful, perhaps even preferable, regardless of scale. Thus, this paper proposes criteria conceived to …


Asic Design Of Rf Energy Harvester Using 0.13um Cmos Technology, Jainish K. Zaveri Aug 2018

Asic Design Of Rf Energy Harvester Using 0.13um Cmos Technology, Jainish K. Zaveri

Master's Theses

Recent advances in wireless sensor nodes, data acquisition devices, wearable and implantable medical devices have paved way for low power (sub 50uW) devices. These devices generally use small solid state or thin film batteries for power supply which need replacement or need to be removed for charging. RF energy harvesting technology can be used to charge these batteries without the need to remove the battery from the device, thus providing a sustainable power supply. In other cases, a battery can become unnecessary altogether. This enables us to deploy wireless network nodes in places where regular physical access to the nodes …


Iris Biometric Identification Using Artificial Neural Networks, Kevin Joseph Haskett Aug 2018

Iris Biometric Identification Using Artificial Neural Networks, Kevin Joseph Haskett

Master's Theses

A biometric method is a more secure way of personal identification than passwords. This thesis examines the iris as a personal identifier with the use of neural networks as the classifier. A comparison of different feature extraction methods that include the Fourier transform, discrete cosine transform, the eigen analysis method, and the wavelet transform, is performed. The robustness of each method, with respect to distortion and noise, is also studied.


The Development And Validation Of Sinatra: A Three-Dimensional Direct Simulation Monte Carlo (Dsmc) Code Written In Object-Oriented C++ And Performed On Cartesian Grids, David Matthew Galvez Aug 2018

The Development And Validation Of Sinatra: A Three-Dimensional Direct Simulation Monte Carlo (Dsmc) Code Written In Object-Oriented C++ And Performed On Cartesian Grids, David Matthew Galvez

Master's Theses

The field of Computational Fluid Dynamics (CFD) primarily involves the approximation of the Navier-Stokes equations. However, these equations are only valid when the flow is considered continuous such that molecular interactions are abundant and predictable. The Knudsen number, $Kn$, which is defined as the ratio of the flow's mean free path, $\lambda$, to some characteristic length, $L$, quantifies the continuity of any flow, and when this parameter is large enough, alternative methods must be employed to simulate gases. The Direct Simulation Monte Carlo (DSMC) method is one which simulates rarefied gas flows by directly simulating the particles that compose the …


Power System Spoof Detection With A Hybrid Hardware/Software Benchmarking Framework, Keaton Dieter, Ben Mccamish, Eduardo Cotilla-Sanchez, Robert B. Bass, Scott Wallace, Xinghui Zhao Aug 2018

Power System Spoof Detection With A Hybrid Hardware/Software Benchmarking Framework, Keaton Dieter, Ben Mccamish, Eduardo Cotilla-Sanchez, Robert B. Bass, Scott Wallace, Xinghui Zhao

Electrical and Computer Engineering Faculty Publications and Presentations

The integration of monitoring and control networks at different voltage levels and across utility boundaries has made it harder to maintain and assess the resilience of power systems due to increasing cyber attacks. On the software side, a variety of research efforts pursue cyber protection algorithms, such as spoof detection techniques. On the hardware and firmware side, research has demonstrated the feasibility of adversarial attacks by providing an entry point at the device level. This work proposes and evaluates two detection performance metrics for a variety of cyber spoofing attacks introduced in a realistic Phasor Measurement Unit (PMU) network for …