Engineering Commons^™

A Spatio-Temporal Model Reveals Self-Limiting Fcɛri Cross-Linking By Multivalent Antigens, Md Shahinuzzaman, Jawahar Khetan, Dipak Barua

Chemical and Biochemical Engineering Faculty Research & Creative Works

Aggregation of cell surface receptor proteins by multivalent antigens is an essential early step for immune cell signalling. A number of experimental and modelling studies in the past have investigated multivalent ligand-mediated aggregation of IgE receptors (FcɛRI) in the plasma membrane of mast cells. However, understanding of the mechanisms of FcɛRI aggregation remains incomplete. Experimental reports indicate that FcɛRI forms relatively small and finite-sized clusters when stimulated by a multivalent ligand. By contrast, modelling studies have shown that receptor cross-linking by a trivalent ligand may lead to the formation of large receptor superaggregates that …

Early Term Effects Of Rhbmp-2 On Pedicle Screw Fixation In A Sheep Model: Histomorphometric And Biomechanical Analyses, Jeffrey M. Toth, Mei Wang, Chetan Patel, Akshi Arora

Biomedical Engineering Faculty Research and Publications

Background: The effects of recombinant human bone morphogenetic protein-2 (rhBMP-2) on pedicle screw pullout force and its potential to improve spinal fixation have not previously been investigated. rhBMP-2 on an absorbable collagen sponge (ACS) carrier was delivered in and around cannulated and fenestrated pedicle screws in a sheep lumbar spine instability model. Two control groups (empty screw and ACS with buffer) were also evaluated. We hypothesized that rhBMP-2 could stimulate bone growth in and around the cannulated and fenestrated pedicle screws to improve early bone purchase.

Methods: Eight skeletally mature sheep underwent destabilizing laminectomies at L2–L3 and L4–L5 followed by …

Cooperative Interference Control In Neighboring Passive Scattering Antennas, Shadi Ebrahimi-Asl, Mohammad Tayeb Ahmad Ghasr, Maciej Zawodniok

Electrical and Computer Engineering Faculty Research & Creative Works

Passive backscattering links in scattering sensor arrays suffer from mutual coupling among closely spaced neighbor antennas. This effect results in an unmatched circuitry at input ports of antennas causing poor power harvesting, weak backscattering, overall low read rates. In this paper, a model for mutual coupling in a $N$ by $N$ scattering antenna arrays is discussed. We show by simulations and measurements that in a two-scatterer system (one target and one neighbor antennas) the mutual coupling effect from the neighbor to the target varies depending on its load and also its location with respect to the target and the incident …

Enhancing 3d Visual Odometry With Single-Camera Stereo Omnidirectional Systems, Carlos A. Jaramillo

Dissertations, Theses, and Capstone Projects

We explore low-cost solutions for efficiently improving the 3D pose estimation problem of a single camera moving in an unfamiliar environment. The visual odometry (VO) task -- as it is called when using computer vision to estimate egomotion -- is of particular interest to mobile robots as well as humans with visual impairments. The payload capacity of small robots like micro-aerial vehicles (drones) requires the use of portable perception equipment, which is constrained by size, weight, energy consumption, and processing power. Using a single camera as the passive sensor for the VO task satisfies these requirements, and it motivates the …

Investigation Of A Pressure Wave Supercharger For An Industrial Diesel Engine, Brian A. Beasley

Theses and Dissertations

Internal combustion engines suffer from decreased performance as altitude is in- creased. This performance decrease can be overcome by increasing the pressure in the engine's intake manifold. Typically, this is accomplished with a turbocharger or supercharger. However, mechanical compression devices such as these suffer from decrease compression efficiency as the size of the device decreases. The size of the compression device scales with the amount of mass ow through the device, and the amount of mass ow is proportional to the size of the engine. This means a small turbocharger for a small engine is less efficient than a larger …

Arrhenius Rate Chemistry Informed Inter-Phase Source Terms (Arciist) For Macro-Scale Explosive Hydrocodes, Matthew J. Schwaab

Theses and Dissertations

A critical factor in hydrocodes designed to simulate explosive material is defining the chemical reaction rate under various conditions. This rate determines how quickly the granular solid explosive is converted to its gaseous products. Currently, the state of the art for macro-scale hydrocodes is to use one of numerous burn models. These burn models are designed to estimate the bulk chemical reaction rate. Unfortunately, these burn rate models are largely based on empirical data and must be recalibrated for every new material being simulated. This research proposes that the use of Arrhenius Rate Chemistry Informed Interphase Source Terms (ARCIIST) in …

Multidisciplinary Design Optimization Of Life Cycle Benefit Of Trimarans Using Monte Carlo Method, Lin Du

Theses and Dissertations

This thesis presents a methodology for multidisciplinary design and optimization (MDO) of the life cycle benefit (LCB) of trimarans. Unlike naval vessels which have a robust fire power and other capabilities which are very difficult to be quantified, the essence of a commercial ship’s construction and operation is an investment. The ship owners must consider the benefits accruing from lifelong development/deployment of a commercial vessel, taking in to account the construction time, interest rate, cost of operation, maintenance, drydocking, annual revenue, etc. Whether or not a ship design has outstanding economic potential, depends on only one standard value in the …

Self-Assembly Of Protein Fibrils In Microgravity, Dylan Bell

Theses and Dissertations

Deposits of insoluble protein fibrils in human tissue are associated with amyloidosis and neurodegenerative diseases. Different proteins are involved in each disease; all are soluble in their native conformation in vivo, but by molecular self-assembly, they all form insoluble protein fibril deposits with a similar cross -sheet structure. The study of molecular self-assembly is also of interest to origin of life. The development of cellular activity was dependent upon the creation of large complex molecular structures in the chemical and environmental conditions present when life originated. Although life probably arose in a planetary environment, microgravity is known to effect cellular …

Mathematical Modeling And Empirical Validation Of A Conceptual Exoskeleton For Astronaut Glove Augmentation, Joseph Kissling

Masters Theses

Space presents numerous difficulties for astronauts conducting their work, not the least of which is the spacesuit that is worn to protect them from space. It has long been known that a spacesuit is difficult to work in, especially the rigid and pressurized gloves that put strain on the astronaut's hands, frequently leading to injuries. Astronaut gloves inhibit more than 50% of their strength in some cases [1]. NASA and other space agencies have been working to alleviate these problems by attempting to mechanically augment the gloves to reduce the exertions of the astronaut. To date, no augmentation systems have …

Three-Dimensional Wall Effects In A Scramjet Cavity Flameholder, Evan P. Oren

Theses and Dissertations

Scramjets, or supersonic combustion ramjets, are a key component for the development of powered hypersonic vehicles. The flameholding strategy used in this engine creates a recirculation region by creating a cavity in one side of the combustor. This highly unsteady region is difficult to interrogate through conventional means. A novel optical observation technique called hyperspectral imaging has been developed to examine the scramjet combustion chamber. The hyperspectral camera is capable of generating an interferogram at hundreds to thousands of wavelengths. These data are integrated across the line-of-sight with no information on three-dimensional (3D) location of origin. A model must be …

Multi-Level Multi-Objective Programming And Optimization For Integrated Air Defense System Disruption, Aaron M. Lessin

Theses and Dissertations

The U.S. military's ability to project military force is being challenged. This research develops and demonstrates the application of three respective sensor location, relocation, and network intrusion models to provide the mathematical basis for the strategic engagement of emerging technologically advanced, highly-mobile, Integrated Air Defense Systems. First, we propose a bilevel mathematical programming model for locating a heterogeneous set of sensors to maximize the minimum exposure of an intruder's penetration path through a defended region. Next, we formulate a multi-objective, bilevel optimization model to relocate surviving sensors to maximize an intruder's minimal expected exposure to traverse a defended border region, …

Non-Destructive Characterization Of Rotated Uniaxial Anisotropic Materials, Alexander G. Knisely

Theses and Dissertations

Electromagnetic material characterization of anisotropic media requires measurement diversity, minimal measurement uncertainty and insight into sample symmetry. Additionally, non-destructive characterization techniques are valued over legacy measurement techniques because a destructive approach requires sample preparation to execute a measurement. A Single Port Waveguide Probe (SPWP) non-destructive material characterization technique is proposed to accommodate measuring a metal backed, known thickness, rotated uniaxial anisotropic material. A rotated uniaxial sample possesses unique transverse constitutive components and a longitudinal constitutive component which is the same as one of the transverse values. The SPWP consists of a rectangular waveguide aperture cut in the center of a …

Neutron Spectroscopy Using Rubberized Eu:Licaf Wafers, Michael A. Ford

Theses and Dissertations

With the increasing cost and decreasing availability of ³He, there have been many efforts to find alternative neutron detection materials. Lithium calcium aluminum fluoride (LiCAF) enriched to 95% ⁶Li doped with europium was evaluated here as a replacement material for ³He, based on the absorption of thermalized neutrons by the ⁶Li and subsequent energy release of the ⁶Li(n,t)⁴He reaction. Wafers 0.5 cm thick, consisting of LiCAF crystals in a rubberized matrix, were embedded with wavelength shifting fibers (WSF) and mated to silicon photo-multipliers (SiPMs) to measure the photon response in a flux of …

Combustion Dynamics And Heat Transfer In An Ultra Compact Combustor, Brian T. Bohan

Theses and Dissertations

The Ultra Compact Combustor (UCC) is an innovative combustion system alternative to a traditional turbine engine burner with the potential to improve engine efficiency with a reduced combustor volume. The UCC shortens the axial length of the combustor, and therefore reduces engine weight, by burning in an annulus and swirling the reactants in the circumferential direction. These length and weight improvements can directly lead to an increased thrust-to-weight rating of the engine. The present research included five objectives which advanced the UCC concept on four fronts; cooling UCC turbine vanes, advanced computational modeling of UCC systems, system air split control …

Thermochemical Non-Equilibrium Models For Weakly Ionized Hypersonic Flows With Application To Slender-Body Wakes, Matthew P. Clarey

Theses and Dissertations

The current resurgence of interest in hypersonic technologies has warranted an inquiry into the commonly employed thermochemical non-equilibrium models within computational fluid dynamic (CFD) simulations. Additionally, research has historically focused on forebody flowfields, while studies of the complex wake structure have remained elusive. Although the forebody is of significance for vehicle analysis, the wake presents many exploitative characteristics. This dissertation aimed to address these two deficits. First, two three-temperature non-equilibrium models were developed, increasing the fidelity of hypersonic solutions above that of the legacy two-temperature model. The models were then investigated via zero-dimensional simulations, to detail the non-equilibrium processes, and …

Thermal Transport At Superhydrophobic Surfaces In Impinging Liquid Jets, Natural Convection, And Pool Boiling, Matthew Clark Searle

Theses and Dissertations

This dissertation focuses on the effects of superhydrophobic (SHPo) surfaces on thermal transport. The work is divided into two main categories: thermal transport without phase change and thermal transport with phase change. Thermal transport without phase change is the topic of four stand-alone chapters. Three address jet impingement at SHPo surfaces and the fourth considers natural convection at a vertical, SHPo wall. Thermal transport with phase change is the topic of a single stand-alone chapter exploring pool boiling at SHPo surfaces. Two chapters examining jet impingement present analytical models for thermal transport; one considered an isothermal wall and the other …

Use Of The Wilshire Equations To Correlate And Extrapolate Creep Data Of Hr6w And Sanicro 25, Vito Cedro Iii, Christian Garcia, Mark Render

Mechanical Engineering Faculty Publications

Advanced power plant alloys must endure high temperatures and pressures for durations at which creep data are often not available, necessitating the extrapolation of creep life. Many methods have been proposed to extrapolate creep life, and one of recent significance is a set of equations known as the Wilshire equations. With this method, multiple approaches can be used to determine creep activation energy, increase the goodness of fit of available experimental data, and improve the confidence level of calculating long-term creep strength at times well beyond the available experimental data. In this article, the Wilshire equation is used to extrapolate …

The Correlation Between Energy Cost Share, Human, And Economic Development Using Time Series Data From Australasia, Europe, North America, And The Brics Nations, Ryan Roberts, Josephine Kaviti Musango, Alan Colin Brent, Matthew K. Heun

University Faculty Publications and Creative Works

This paper investigates how a change in a region's energy cost share (ECS), a ratio of a region's energy expenditure as a fraction of its gross domestic product (GDP), affects the region's social and economic development. Nations from four regions of the world, namely Australasia, Europe, North America, and the BRICS nations (Brazil, Russia, India, China, and South Africa) were chosen for this study. Using time series data from the period of 1978 to 2010, the annual ECS of each country was compared to the year-on-year GDP change, as well as the components of the human development index (HDI). High …

Androparse - An Android Feature Extraction Framework & Dataset, Robert Schmicker, Frank Breitinger, Ibrahim Baggili

Electrical & Computer Engineering and Computer Science Faculty Publications

Android malware has become a major challenge. As a consequence, practitioners and researchers spend a significant time analyzing Android applications (APK). A common procedure (especially for data scientists) is to extract features such as permissions, APIs or strings which can then be analyzed. Current state of the art tools have three major issues: (1) a single tool cannot extract all the significant features used by scientists and practitioners (2) Current tools are not designed to be extensible and (3) Existing parsers do not have runtime efficiency. Therefore, this work presents AndroParse which is an open-source Android parser written in Golang …

Identifying Criteria To Predict Army Rifle Marksmanship Proficiency, Katlin Makina Anglin

Doctoral Dissertations and Master's Theses

The United States Army requires each Soldier to develop marksmanship proficiency in an effort to achieve combat readiness. Soldiers currently develop marksmanship proficiency through Basic Rifle Marksmanship (BRM) training, but significant skill deficiencies are apparent at the end of training. These skill deficiencies remain throughout training because instructors rarely assess Soldiers objectively before the final qualification, reducing the opportunity for instructors to diagnose skill deficiencies until it is too late. Therefore, the goal of the current research is to identify individual differences and sensor-based performance measures for inclusion in a formative assessment during BRM training. The results of the current …

Hybrid-Cooled Data Center Server Layout Optimization For Air-Side Heat Recovery, Assel Sakanova, Sajad Alimohammadi, Jaakko Mcevody, Tim Persoons

Conference Papers

The rapid increase in energy demand for data center requires improved cooling techniques. This study investigates, numerically and experimentally, the energy efficiency optimization based on server level air flows and also identifies the potential for waste heat recovery from the air stream for a hybrid air/liquid cooled server. Multi-objective genetic algorithm and entropy generation minimization are chosen as tools to address the multiple objectives involved in the problem and examine the cooling performance and waste heat recovery potential. Selected experimental measurements have successfully validated the CFD simulation model.

Examining The Microeconomics Of Bid Difference Of Engineer & Contractor Bids In Highway Construction, Robert Ryan, Randy R. Rapp, Mark Shaurette, Sarah Hubbard

The Professional Constructor

This study examines microeconomic factors that affect Bid Difference between the designer’s Engineer’s Estimate and the contractor’s Winning Bid. Historically, the accuracy of the Engineer’s Estimate and the Winning Bid vary. To account for this discrepancy, the Federal Highway Administration (FHWA) recommends a contingency be included in all Engineer’s Estimates. Statistical analysis was performed to determine if state Departments of Transportation (DOTs) were currently meeting the recommended Bid Difference values. Data was collected from California, North Carolina, and Ohio from 2012 through 2014. Statistical analysis indicates that current practices to develop an Engineer’s Estimate met the FHWA recommended values. With …

Designing A Modular Building: A Case Study For Modular Vs.Conventional Design For An Apartment Building, Christine Piper, Arun Thodupunoori

The Professional Constructor

To alleviate the diminishing number of tradespeople in the US construction industry, modular construction is an alternative construction process that could be used for repetitive construction applications. However, there are some misconceptions about modular construction including: limited architectural design options, design restrictions, lower quality, unaffordable and inability to design for sustainability. Modular construction is a process that streamlines the construction process and saves a significant amount of time while delivering a high quality building. In response to the misconception of design options, this case study presents the design considerations for transforming an apartment building that was designed and constructed using …

Blockchain Based Efficient And Robust Fair Payment For Outsourcing Services In Cloud Computing, Yinghui Zhang, Robert H. Deng, Ximeng Liu, Dong Zheng

Research Collection School Of Computing and Information Systems

As an attractive business model of cloud computing, outsourcing services usually involve online payment and security issues. The mutual distrust between users and outsourcing service providers may severely impede the wide adoption of cloud computing. Nevertheless, most existing payment solutions only consider a specific type of outsourcing service and rely on a trusted third-party to realize fairness. In this paper, in order to realize secure and fair payment of outsourcing services in general without relying on any third-party, trusted or not, we introduce BCPay, a blockchain based fair payment framework for outsourcing services in cloud computing. We first present the …

Secondary Frequency Stochastic Optimal Control In Independent Microgrids With Virtual Synchronous Generator-Controlled Energy Storage Systems, Ting Yang, Yajian Zhang, Zhaoxia Wang, Haibo Pen

Research Collection School Of Computing and Information Systems

With the increasing proportion of renewable energy in microgrids (MGs), its stochastic fluctuation of output power has posed challenges to system safety and operation, especially frequency stability. Virtual synchronous generator (VSG) technology, as one effectivemethod, was used to smoothen frequency fluctuation and improve the system's dynamic performance,which can simulate the inertia and damping of the traditional synchronous generator. This study outlines the integration of VSG-controlled energy storage systems (ESSs) and traditional synchronous generators so they jointly participate in secondary frequency regulation in an independent MG. Firstly, a new uncertain state-space model for secondary frequency control is established, considering the measurement …

Application And Usage Of Design-Build By State Dots, Dennis Bausman, Mashrur Chowdhury, Christopher Cummings, Sasi Selvan

The Professional Constructor

This study examines the usage of design-build by the Department of Transportation (DOT) of the 50 states in the United States. Design-build has been growing in popularity as a procurement form in both the private and public sectors, and in the last ten years many DOTs have started or expanded programs to use design-build for infrastructure projects. However, many DOTs are still struggling to determine the best application of design build and how to incorporate its use as a procurement method for DOT projects. This study examines how state DOTs are using design-build, when they are using this delivery method, …

Assessment Of Electrical Contractors’ Perception And Practices With Project Risk Management, Anthony J. Perrenoud

The Professional Constructor

Project Risk Management is a critical construction management skillset for identifying risks, assessing risks, strategizing, and executing risk mitigation plans. Proactive risk management has been found to reduce negative impacts to project objectives and increase customer satisfaction. To improve project risk management contractors have a method of measuring perceptions and practices of risk management, also known as risk maturity. Previous research has identified a model for measuring five major attributes of risk maturity they are (1) management’s perspective of risk management; (2) organizational risk culture; (3) risk identification; (4) risk analysis; and, (5) standardized risk management process. This study presents …

Standardization Of Fatigue Characteristics Of Cement-Treated Aggregate Base Materials Under Different Stress States, Jiawei Xie, Limin Tang, Songtao Lv, Naitian Zhang, Tuo Huang, Hongfu Liu

Michigan Tech Publications, Part 1

In this study, to decrease the evaluation uncertainty of the fatigue characteristics of cement-treated aggregate base materials under different test conditions, unconfined compressive, indirect tensile, flexural tensile strength tests and fatigue tests of these base materials with different cement content and at different curing times were carried out. The Weibull distribution was employed to analyze fatigue test results. The standardization model of fatigue characteristics for cement-treated aggregate base materials under different stress states was established. Based on the interval analysis theory, the fatigue characteristic model under different stress states was established using interval parameters. Results revealed that the curing time …

Collaborative Risk Mitigation Through Construction Planning And Scheduling, Lane Kay Coble

The Professional Constructor

No abstract provided.

Construction Disputes In The United States And The United Kingdom: A Comparison, Anusree Saseendran, Ben F. Bigelow, Zofia Rybkowski, Dawn Jourdan

The Professional Constructor

Construction disputes are on the rise globally. They adversely affect the progress and quality of a construction project by resulting in cost overruns and delays. They are also time-consuming and expensive to resolve. Hence it is valuable to identify the most disputed topics in construction in the US and compare them to those in a different country. This helps better understand disputes, and the influence that culture and the difference in the nature of construction in the regions may have on disputes. This study was an attempt to identify and compare the most disputed topics in construction in the United …