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Full-Text Articles in Engineering

Inspire E-News 5 2017, College Of Engineering And Applied Sciences May 2017

Inspire E-News 5 2017, College Of Engineering And Applied Sciences

College of Engineering and Applied Sciences News

  • WMU assistant professor receives $500,000 NSF CAREER Award
  • Entrepreneurial engineer wins Brian Patrick Thomas Award
  • Formula SAE team competes at Michigan International Speedway
  • $318,000 grant will support research efforts of Department of Defense


Assessing The Importance Of The Root Mean Square (Rms) Value Of Different Waveforms To Determine The Strength Of A Dielectrophoresis Trapping Force, Jordan Gilmore, Monsur Islam, Josie Duncan, Rucha Nato, Rodrigo Martinez-Duarte May 2017

Assessing The Importance Of The Root Mean Square (Rms) Value Of Different Waveforms To Determine The Strength Of A Dielectrophoresis Trapping Force, Jordan Gilmore, Monsur Islam, Josie Duncan, Rucha Nato, Rodrigo Martinez-Duarte

Publications

No abstract provided.


Assessing The Importance Of The Root Mean Square (Rms) Value Of Different Waveforms To Determine The Strength Of A Dielectrophoresis Trapping Force, Jordon Gilmore, Monsur Islam, Josie Duncan, Rucha Natu, Rodrigo Martinez-Duarte May 2017

Assessing The Importance Of The Root Mean Square (Rms) Value Of Different Waveforms To Determine The Strength Of A Dielectrophoresis Trapping Force, Jordon Gilmore, Monsur Islam, Josie Duncan, Rucha Natu, Rodrigo Martinez-Duarte

Publications

No abstract provided.


Do Single-Use Medical Devices Containing Biopolymers Reduce The Environmental Impacts Of Surgical Procedures Compared With Their Plastic Equivalents?, Scott R. Unger, Troy A. Hottle, Shakira R. Hobbs, Cassandra L. Thiel, Nicole Campion, Melissa M. Bilec, Amy E. Landis May 2017

Do Single-Use Medical Devices Containing Biopolymers Reduce The Environmental Impacts Of Surgical Procedures Compared With Their Plastic Equivalents?, Scott R. Unger, Troy A. Hottle, Shakira R. Hobbs, Cassandra L. Thiel, Nicole Campion, Melissa M. Bilec, Amy E. Landis

Publications

Background: While petroleum-based plastics are extensively used in health care, recent developments in biopolymer manufacturing have created new opportunities for increased integration of biopolymers into medical products, devices and services. This study compared the environmental impacts of single-use disposable devices with increased biopolymer content versus typically manufactured devices in hysterectomy.

Methods: A comparative life cycle assessment of single-use disposable medical products containing plastic(s) versus the same single-use medical devices with biopolymers substituted for plastic(s) at Magee-Women’s Hospital (Magee) in Pittsburgh, PA and the products used in four types of hysterectomies that contained plastics potentially suitable for biopolymer substitution. Magee is …


Wettability Tailoring Of Nanotube Carpets: Morphology-Chemistry Synergy For Hydrophobic–Hydrophilic Cycling, Lymeng He, Anil Karumuri, Sharmila M. Mukhopadhyay May 2017

Wettability Tailoring Of Nanotube Carpets: Morphology-Chemistry Synergy For Hydrophobic–Hydrophilic Cycling, Lymeng He, Anil Karumuri, Sharmila M. Mukhopadhyay

Mechanical and Materials Engineering Faculty Publications

Carpet-like arrays of carbon nanotubes (CNTs) on graphitic carbon materials have been investigated in order to understand all-carbon hierarchical structures for multifunctional surface-active devices. Pure CNT carpets are seen to be super-hydrophobic as long as they are well aligned. For future applications involving aqueous environments, the ability to tailor the surface wettability and switch it on demand can be very useful, and enable unprecedented devices related to microfluidics, catalysis and sensing/detection systems. In this study, microwave plasma treatments were used to functionalize CNT carpets for a progressive increase in wettability so that they could eventually become super-hydrophilic. This change could …


Understanding N-Nitrosodimethylamine Formation In Water: Chloramine Chemistry, Kinetics, And A Proposed Reaction Pathway, Huong Thu Pham May 2017

Understanding N-Nitrosodimethylamine Formation In Water: Chloramine Chemistry, Kinetics, And A Proposed Reaction Pathway, Huong Thu Pham

Graduate Theses and Dissertations

The formation of N-nitrosodimethylamine (NDMA) in drinking water systems is a concern because of its potential carcinogenicity and occurrence at toxicologically relevant levels. The postulated mechanism for NDMA formation involves a substitution between dichloramine and amine-based precursors to form an unsymmetrical dimethylhydrazine (UDMH), which is then oxidized by ground-state molecular oxygen to form NDMA. However, this latter reaction is spin forbidden, thus likely occurs at a slow rate. It is hypothesized that the reaction between monochloramine and hydroxylamine (a nitrification product) may form an intermediate, which is involved in the NDMA formation pathway. This intermediate may also be generated from …


Computer Simulation Of Pore Migration Due To Temperature Gradients In Nuclear Oxide Fuel, Ian Wayne Vance May 2017

Computer Simulation Of Pore Migration Due To Temperature Gradients In Nuclear Oxide Fuel, Ian Wayne Vance

Graduate Theses and Dissertations

A phase-field simulation model is being presented that captures the thermal-gradient-driven migration of pores in oxide fuel associated with fuel restructuring. The model utilizes a Cahn-Hilliard equation supplemented with an advection term to describe the vapor transport of fuel material through the pore interior due to gradients in vapor pressure. In addition, the model also captures changes in a migrating pores’ morphology. Simulations demonstrate that the model successfully predicts pore migration towards the hottest portion of the fuel, the centerline. The simulations also demonstrate changes in pore shape that are in agreement with previous experimental observations. Initially isotropic pores are …


Exploring Compaction Effects On Cold In-Place Recycling Mixtures Using Emulsified Asphalt, Erica Ann Yeung May 2017

Exploring Compaction Effects On Cold In-Place Recycling Mixtures Using Emulsified Asphalt, Erica Ann Yeung

Graduate Theses and Dissertations

Cold in-place recycling (CIR) is a process that takes three to four inches of existing pavement surface and reuses 100% of it by milling and crushing it, adding asphalt emulsions and/or additives to it, before placing and re-compacting it. There is currently very little research regarding the interaction between the crushed aggregate and asphalt emulsion during the CIR process. In this study, the interactions between the combinations of crushed aggregates and asphalt emulsions were investigated along with select compaction metrics and a raveling performance test. The three types of aggregates included coated limestone, recycled asphalt pavement (RAP), and coated syenite. …


Feasibility Of Additive Manufactured Materials For Use In Geotechnical Laboratory Testing Applications, Matthew P. Watters May 2017

Feasibility Of Additive Manufactured Materials For Use In Geotechnical Laboratory Testing Applications, Matthew P. Watters

Graduate Theses and Dissertations

The factors affecting the positive volumetric strain, or dilatancy, typically observed in response to shearing of a dense granular material have long been investigated; however, there still lacks a direct relationship between particle shapes and the resulting dilatant response. The typical Mohr-Coulomb strength parameter associated with granular material is known as the effective friction angle (φ’). For a dense granular assemblage, the peak friction angle has been described as being comprised of a dilatant friction angle (φ’d) component and a critical state friction angle (φ’cv) component. While the topic of dilatancy and factors (both inherent and extrinsic) affecting its behavior …


Characterization Of Plastic Deformation Evolution In Single Crystal And Nanocrystalline Cu During Shock By Atomistic Simulations, Mehrdad Mirzaei Sichani May 2017

Characterization Of Plastic Deformation Evolution In Single Crystal And Nanocrystalline Cu During Shock By Atomistic Simulations, Mehrdad Mirzaei Sichani

Graduate Theses and Dissertations

The objective of this dissertation is to characterize the evolution of plastic deformation mechanisms in single crystal and nanocrystalline Cu models during shock by atomistic simulations. Molecular dynamics (MD) simulations are performed for a range of particle velocities from 0.5 to 1.7 km/s and initial temperatures of 5, 300 and 600 K for single crystal models as well as particle velocities from 1.5 to 3.4 km/s for nanocrystalline models with grain diameters of 6, 11, 16 and 26 nm. For single crystal models, four different shock directions are selected, <100>, <110>, <111> and <321>, and dislocation density behind the shock wave …


Total N-Nitrosamine Precursor Adsorption With Carbon Nanotubes: Elucidating Controlling Physiochemical Properties And Developing A Size-Resolved Precursor Surrogate, Erin Needham May 2017

Total N-Nitrosamine Precursor Adsorption With Carbon Nanotubes: Elucidating Controlling Physiochemical Properties And Developing A Size-Resolved Precursor Surrogate, Erin Needham

Graduate Theses and Dissertations

As drinking water sources become increasingly impaired with nutrients and wastewater treatment plant (WWTP) effluent, formation of disinfection byproducts (DBPs) – such as trihalomethanes (THMs), dihaloacetonitriles (DHANs), and N-nitrosamines – during water treatment may also increase. N-nitrosamines may comprise the bulk of the chronic toxicity in treated drinking waters despite forming at low ng/L levels. This research seeks to elucidate physicochemical properties of carbon nanotubes (CNTs) for removal of DBP precursors, with an emphasis on total N-nitrosamines (TONO).

Batch experiments with CNTs were completed to assess adsorption of THM, DHAN, and TONO precursors; physiochemical properties of CNTs were quantified through …


Development Of A Multiband Remote Sensing System For Determination Of Unsaturated Soil Properties, Cyrus D. Garner May 2017

Development Of A Multiband Remote Sensing System For Determination Of Unsaturated Soil Properties, Cyrus D. Garner

Graduate Theses and Dissertations

A multiband system including active microwave sensing and visible-near infrared reflectance spectroscopy was developed to measure unsaturated soil properties in both field and laboratory environments. Remote measurements of soil volumetric water content (θv), soil water matric potential (ψ), and soil index properties (liquid limit [LL], plastic limit [PL], and clay fraction [CF]) were conducted. Field-based measurement of θv was conducted using a ground-based radar system and field measurements within 10 percentage points of measurements acquired with traditional sampling techniques were obtained. Laboratory-based, visible and near infrared spectroscopy was found to be capable of obtaining empirical, soil specific regression functions (partial …


Trihalomethane, Dihaloacetonitrile, And Total N-Nitrosamine Precursor Adsorption By Carbon Nanotubes: The Importance Of Surface Oxides And Pore Volume, Erin Needham May 2017

Trihalomethane, Dihaloacetonitrile, And Total N-Nitrosamine Precursor Adsorption By Carbon Nanotubes: The Importance Of Surface Oxides And Pore Volume, Erin Needham

Graduate Theses and Dissertations

As drinking water sources become increasingly impaired, enhanced removal of natural organic matter (NOM) may be required to curb formation of disinfection byproducts (DBPs) upon chlor(am)ination. While carbon nanotubes (CNTs) can adsorb NOM, their properties for DBP precursor adsorption have not been elucidated. Nine types of CNTs were assessed for trihalomethane (THM), dihaloacetonitrile (DHAN), and total N-nitrosamine (TONO) precursor adsorption. Batch isotherm experiments were completed with lake water and, to simulate an impaired condition, effluent from a wastewater treatment plant (WWTP). Adsorption varied with CNT type and dose, with TONO precursors having the highest percent removals from WWTP effluent (up …


Effect Of Column Axial Load On Skewed Smf Rbs Connection Demands, Clovis Desrochers May 2017

Effect Of Column Axial Load On Skewed Smf Rbs Connection Demands, Clovis Desrochers

Graduate Theses and Dissertations

Steel buildings in high seismic areas often require special structural systems to transfer large lateral forces induced by earthquake accelerations. The selection of an appropriate seismic steel system (braced frame, moment frame, shear wall, etc.) is often influenced by architectural considerations. Moment frame configurations offer the most architectural flexibility, but are limited by code prequalification requirements that limit the use of non-orthogonal (skewed) beam-column connection geometries. A recent study has investigated laterally skewed moment frame connections, indicating that skew increases the potential for column twist and column flange yielding; however, it is unclear how realistic column axial loads will affect …


Numerical Simulation Of Metallic Uranium Sintering, Bruce Berry May 2017

Numerical Simulation Of Metallic Uranium Sintering, Bruce Berry

Graduate Theses and Dissertations

Conventional ceramic oxide nuclear fuels are limited in their thermal and life-cycle properties. The desire to operate at higher burnups as is required by current utility economics has proven a formidable challenge for oxide fuel designs. Metallic formulations have superior thermal performance but are plagued by volumetric swelling due to fission gas buildup. In this study, we consider a number of specific microstructure configurations that have been experimentally shown to exhibit considerable resistance to porosity loss. Specifically, a void sizing that is bimodally distributed was shown to resist early pore loss and could provide collection sites for fission gas buildup. …


Feasibility Of Using Oxide Thickness Measurements For Predicting Crack Growth Rates In P91 Steel Components, Ralph Edward Huneycutt Iv May 2017

Feasibility Of Using Oxide Thickness Measurements For Predicting Crack Growth Rates In P91 Steel Components, Ralph Edward Huneycutt Iv

Graduate Theses and Dissertations

There are only few methods available for predicting the age of cracks that are found in high

temperature structural components during service; among the promising ones is the oxide

thickness measurement technique. Oxide thickness profiles are taken from crack surfaces of

components and used for predicting the rates of crack propagation. This technique is particularly

suitable for high temperature components fabricated from ferritic steels commonly used in power

plants that run on fossil fuels. To implement this technique, it is necessary to fully understand the

kinetics of high temperature oxidation in these steels. In this study, the oxidation characteristics

of …


A Comparison Of Force And Pressure Coefficients On Dome, Cube And Prism Shaped Buildings Due To Straight And Tornadic Wind Using Three Dimensional Computational Fluids Dynamics, Majdi A. A. Yousef May 2017

A Comparison Of Force And Pressure Coefficients On Dome, Cube And Prism Shaped Buildings Due To Straight And Tornadic Wind Using Three Dimensional Computational Fluids Dynamics, Majdi A. A. Yousef

Graduate Theses and Dissertations

Tornadoes induce very different wind forces than a straight-line (SL) wind. A suitably designed building for a SL wind may fail when exposed to a tornado-wind of the same wind speed. It is necessary to design buildings that are more resistant to tornadoes. Most studies have been conducted to investigate tornado forces on cubic, gable-roof and cylinder buildings. However, little attention has been paid to investigate tornado force on dome buildings; hence, further research is conducted in this study. The forces on a dome, cube and prisms were analyzed and compared using Computational Fluid Dynamics (CFD) for tornadic and SL …


The Intersection Of Manufacturing Technologies And School Music Programs, Leslie Prunier May 2017

The Intersection Of Manufacturing Technologies And School Music Programs, Leslie Prunier

University Scholar Projects

The objective of this project is to design and manufacture a musical instrument, a marching baritone horn, out of plastic. It is constructed out of both PVC pipe and 3D-printed components. Utilizing this project’s documentation, a high school student could use a 3D printer and other basic tools to make their own musical instrument for a fraction of the cost of purchasing one. This documentation will produce a horn tuned in the key of B flat with one functioning valve, and suggestions for future work to make the other two valves functional as well.


Reconfigurable All-Optical De-Multiplexing Via Spatial-Selective Frequency-Up-Conversion In Kai(2) Multimode Waveguide, Young Bong Kwon May 2017

Reconfigurable All-Optical De-Multiplexing Via Spatial-Selective Frequency-Up-Conversion In Kai(2) Multimode Waveguide, Young Bong Kwon

Electrical Engineering Dissertations - Archive

We investigate spatial-mode-selective frequency up-converters in ?(2) multimode waveguides for classical and quantum communication. For the classical application, our method works as spatial-mode de-multiplexer for mode-division-multiplexing (MDM) communication system. For the quantum application, mode-selective quantum frequency conversion (QFC) enables multidimensional quantum encoding (qudits rather than qubits) which could eventually contribute to higher capacity of quantum communication links (higher QKD rates). First, we numerically investigate mode-selective up-conversion in a slab waveguide (2D free space) and periodically-polled KTP (PPKTP) waveguide. A 2D slab waveguide model is proposed based on non-collinear sum frequency generation (SFG). This model enables the calculation of conversion efficiencies …


Sparse Array For Wireless Sensor Networks And Wireless Communications, Hao Liang May 2017

Sparse Array For Wireless Sensor Networks And Wireless Communications, Hao Liang

Electrical Engineering Dissertations - Archive

Underwater target detection and recognition has been widely used nowadays. In this dissertation, we show that the 3-D nested-array system can provide O(N^2) degree of freedom by using only N physical sensors when the second order statistics of the received data is used, which means we can use less sensors to get a better performance. We propose a maximum likelihood (ML) estimation algorithm for underwater target size detection. Theoretical analysis illustrates that our underwater sensor network can tremendously reduce the variance of target estimation. We show that our ML estimator is unbiased and the variance of parameter estimation matches the …


Lung Nodule Detection And Segmentation Using A Patch-Based Multi-Atlas Method, Mustafa Alam May 2017

Lung Nodule Detection And Segmentation Using A Patch-Based Multi-Atlas Method, Mustafa Alam

Electrical Engineering Dissertations - Archive

CT image based lung nodule detection is the most widely used and accepted method for detecting lung cancer. Most CT image based methods rely on supervised learning, which has a high number of false positives and need a large amount of pre-segmented training samples. These problems can be solved if an optimally small number of training sample images can be created, where each sample has lung nodules of similar size and shape as the target image of the actual patient. Based on this hypothesis, two algorithms are proposed for 2D CT images and 3D CT images respectively. Both algorithms use …


Multi-Object Detection And Tracking In Sensor Networks And Video Sequences, Guohua Ren May 2017

Multi-Object Detection And Tracking In Sensor Networks And Video Sequences, Guohua Ren

Electrical Engineering Dissertations - Archive

Firstly the problem of tracking multiple objects using observations acquired at spatially scattered sensors is considered here. Sensors are measuring a sort of signal attenuation from the present targets/sources. Multiple moving targets may die and be born at some point of the monitored period while the states of the sources, e.g. temperature of a fire source, CO/CO2 density of gas source, are also changing with time. In the case of targets tracking, radar signals sent out by sensors and later bounced back from the surface of the targets are measured at sensors, and the task is to find out the …


Gain Scheduling Controller For Aircraft With Mass And Inertia Variation, Eunyoung Kim May 2017

Gain Scheduling Controller For Aircraft With Mass And Inertia Variation, Eunyoung Kim

Mechanical and Aerospace Engineering Dissertations - Archive

Robustness is one of the main control design requirements for aircraft control.Robustness is sought in the stability and performance of closed loop system against various factors such as disturbance, measurement error, modeling error or un-modeled dynamics. In aircraft control design, it is common to assume that the mass and inertia properties of aircraft are constant. Further, aircraft is assumed to have symmetry inits mass distribution relative to its mid-vertical plane. There are, however, cases where the aircraft mass changes rapidly, most notably in aerial refueling operation.The mass change also results in changes in the inertia matrix. An aircraft may also …


On Space Program Planning: Quantifying The Effects Of Spacefaring Goals And Strategies On The Solution Space Of Feasible Programs, Mark Douglas Coley May 2017

On Space Program Planning: Quantifying The Effects Of Spacefaring Goals And Strategies On The Solution Space Of Feasible Programs, Mark Douglas Coley

Mechanical and Aerospace Engineering Dissertations - Archive

An organization's space program represents the coalescence of top-level goals and strategies with the specific, lower-level combinations of mission architectures, hardware, and technology. High costs and long lead times necessitate substantial planning and key decisions to be made years, possibly decades, in advance. Unfortunately, the methods and processes available for planning have historically been unable to provide decision-makers with objective, quantitative information from both the top and lower levels of the space program. Instead, decision-makers are forced to turn to top-level, qualitative assessments, disconnected from any of the fundamental, technical details, where inconsistent comparisons and secondary effects often become the …


Studying Effects Of Adhesive Layer On Electrical Signals Of Piezoelectric Transducer Bonded With Structure, Md Mazharul Islam May 2017

Studying Effects Of Adhesive Layer On Electrical Signals Of Piezoelectric Transducer Bonded With Structure, Md Mazharul Islam

Mechanical and Aerospace Engineering Dissertations - Archive

Piezoelectric wafer active sensors (PWAS) are the most attractive transducers for guided-wave or ultrasound based structural health monitoring (SHM) because of their light weight and compact size. In order to excite guided waves in a structure, the PWASs are usually bonded on the surface of the structure by adhesive materials. The electrical signal applied to the surface bonded PWAS is converted to mechanical deformation of the PWAS which in turn is transferred to the structure through the adhesive layer. Thus, understanding the effects of the adhesive layer on the electrical response of the PWAS enables us to optimize the mechanical …


Nonlinear Model Predictive Control For Cooperative Control And Estimation, Pengkai Ru May 2017

Nonlinear Model Predictive Control For Cooperative Control And Estimation, Pengkai Ru

Mechanical and Aerospace Engineering Dissertations - Archive

Recent advances in computational power have made it possible to do expensive online computations for control systems. It is becoming more realistic to perform computationally intensive optimization schemes online on systems that are not intrinsically stable and/or have very small time constants. Being one of the most important optimization based control approaches, model predictive control (MPC) has attracted a lot of interest from the research community due to its natural ability to incorporate constraints into its control formulation. Linear MPC has been well researched and its stability can be guaranteed in the majority of its application scenarios. However, one issue …


Characterization Of Vertically Split Distribution-Wet Cooling Media Used In Data Centers, Mullaivendhan Varadharasan May 2017

Characterization Of Vertically Split Distribution-Wet Cooling Media Used In Data Centers, Mullaivendhan Varadharasan

Mechanical and Aerospace Engineering Theses - Archive

Data Centers houses substantial number of information technology (IT) equipment like computer servers and storage modules associated with various electronic components which consume high volume of electricity. The IT equipment in data center housing keeps dissipates heat energy as it is constantly running day and night. To keep the data center environment under thermally control and to favor the reliability of electronic components, we need to adopt a cooling technique which aids the module level cooling, with due consideration of the size of the data center and its geographical location. One of the adopted cooling technique in data center thermal …


Composite Plate Optimization With Structural And Manufacturing Constraints, Deepak Polaki May 2017

Composite Plate Optimization With Structural And Manufacturing Constraints, Deepak Polaki

Mechanical and Aerospace Engineering Theses - Archive

This is a design optimization study that focuses on the value of free size optimization technology on composite structures which incorporates realistic structural requirements and practical manufacturing limitations to achieve an iterative design with effective structural performance. To detail a study on such practical implementation, a sample structure is required. A rectangular composite laminate with a central hole cutout is considered for this study and is designed using finite elemental tools which includes compression, tension and shear loading conditions with load reactions at bolted joints and buckling stability. Free size optimization and size optimization are used in this study to …


Reliability Assessment Of Solder Joint Using Bga Package – Megtron 6 Versus Fr4 Printed Circuit Boards, Mugdha Anish Chaudhari May 2017

Reliability Assessment Of Solder Joint Using Bga Package – Megtron 6 Versus Fr4 Printed Circuit Boards, Mugdha Anish Chaudhari

Mechanical and Aerospace Engineering Theses - Archive

When it comes to the mechanical and electrical seam of the Printed Circuit Board (PCB) and package, reliability of the board plays a major impact on PCB. As the frequency increases, losses in signals increase. This necessitates the use of new materials for such applications. Nelco 4000-13EPSI, Rogers 4350B, Panasonic Megtron 6 are few high-speed materials used. Studies have shown that Megtron 6 has the least dielectric losses so far, low transmission loss, high heat resistance and has low weight loss than the FR-4 boards. With an increasing demand for high performance, reliability and lower costs, the field of electronic …


Solder Joints Design Optimization Of Qfn Packages For Different Boards By Investigating Solder Joint Reliability, Rishikesh Vilas Tendulkar May 2017

Solder Joints Design Optimization Of Qfn Packages For Different Boards By Investigating Solder Joint Reliability, Rishikesh Vilas Tendulkar

Mechanical and Aerospace Engineering Theses - Archive

Quad Flat No-lead package (QFN) is one of the most cutting-edge technologies emerged in the market, exhibiting high performance and efficiency with unparalleled cost effectiveness. QFN, a leadless package, is an ideal choice for applications where size, weight thermal and electrical characteristics are critical, particularly in mobile and handheld devices. Applications like automotive, defense and high current circuits require the package to be mounted on thick printed circuit boards (PCB). The motivation of this work is to understand the effect of design variations of solder joints affecting reliability and optimize the solder package to improve reliability for application on different …