Engineering Commons^™

Heuristics From Statistics—Modeling The Behavior And Perception Of Non-Rigid Materials, Vivian C. Paulun, Roland W. Fleming

MODVIS Workshop

No abstract provided.

Modelling Grip Point Selection In Human Precision Grip, Guido Maiello, Lina Klein, Vivian C. Paulun, Roland W. Fleming

MODVIS Workshop

No abstract provided.

Design Of A Very High Efficiency Evaporatively Cooled Mini-Split Air Conditioner, Florida Solar Energy Center, Danny Parker

FSEC Energy Research Center®

An in-house research project at the Florida Solar Energy Center in 2013 was conducted to evaluate the potential of an evaporatively cooled mini-split heat pump. The mini-split heat pump modified was a 1.5-ton Fujitsu model with 19.2 SEER and 10.0 HSPF energy efficiency ratings. Cooling capacity of the system is variable and ranges from 7,000 to 23,000 Btu/h.

We demonstrated that it is possible to improve the energy efficiency of the evaluated mini-split air conditioner by 21% seasonally in Florida's humid climate using an evaporative pre-cooler. Further, we showed the same apparatus was able to improve air conditioner efficiency by …

Investigating Read/Write Aggregation To Exploit Power Reduction Opportunities Using Dual Supply Voltages, Gu Yunfei

McKelvey School of Engineering Graduate Student Theses & Dissertations

Power consumption plays an important role in computer system design today. On-chip memory structures such as multi-level cache make up a significant proportion of total power consumption of CPU or Application-Specific Integrated Circuit (AISC) chip, especially for memory-intensive application, such as floating-point computation and machine learning algorithm. Therefore, there is a clear motivation to reduce power consumption of these memory structures that are mostly consisting of Static Random-Access Memory (SRAM) blocks. In this defense, I will present the framework of a novel dual-supply-voltage scheme that uses separate voltage levels for memory read and write operations. By quantitatively analyzing the cache …

Microstrip Diplexer With Low Channel-Frequency Ratio, Kirti Dhwaj, Li (Lijun) Jun Jiang, Tatsuo Itoh

Electrical and Computer Engineering Faculty Research & Creative Works

The paper presents a microstrip diplexer constructed by joining two stub-perturbed ring resonators at a T-junction. Each ring resonator acts as a bandpass filter with a transmission zero lying very close to the passband of the other filter, thereby increasing the isolation between the two channels. A short stub is additionally added at the T-junction to improve the matching at the common port. The diplexer is able to achieve a channel separation of 50 MHz, with the two channels centered at 2.49 GHz and 2.37 GHz respectively. This translates to a center frequency ratio of 1.05 between the two channels, …

Desulfination By 2′-Hydroxybiphenyl-2-Sulfinate Desulfinase Proceeds Via Electrophilic Aromatic Substitution By The Cysteine-27 Proton, Inacrist Geronimo, Shawn R. Nigam, Christina M. Payne

Chemical and Materials Engineering Faculty Publications

Biodesulfurization is an attractive option for enzymatically removing sulfur from the recalcitrant thiophenic derivatives that comprise the majority of organosulfur compounds remaining in hydrotreated petroleum products. Desulfurization in the bacteria Rhodococcus erythropolis follows a four-step pathway culminating in C–S bond cleavage in the 2′-hydroxybiphenyl-2-sulfinate (HBPS) intermediate to yield 2-hydroxybiphenyl and bisulfite. The reaction, catalyzed by 2′-hydroxybiphenyl-2-sulfinate desulfinase (DszB), is the rate-limiting step and also the least understood, as experimental evidence points to a mechanism unlike that of other desulfinases. On the basis of structural and biochemical evidence, two possible mechanisms have been proposed: nucleophilic addition and electrophilic aromatic substitution. Density …

Bendablesound: An Elastic Multisensory Surface Using Touch-Based Interactions To Assist Children With Severe Autism During Music Therapy, Franceli L. Cibrian, Oscar Peña, Deysi Ortega, Monica Tentori

Engineering Faculty Articles and Research

Neurological Music Therapy uses live music to improve the sensorimotor regulation of children with severe autism. However, they often lack musical training and their impairments limit their interactions with musical instruments. In this paper, we present our co-design work that led to the BendableSound prototype: an elastic multisensory surface encouraging users to practice coordination movements when touching a fabric to play sounds. We present the results of a formative study conducted with 18 teachers showing BendableSound was perceived as “usable” and “attractive”. Then, we present a deployment study with 24 children with severe autism showing BendableSound is “easy to use” …

Cache Power Optimization Using Multiple Voltage Supplies To Exploit Read/Write Asymmetry, Dengxue Yan

McKelvey School of Engineering Graduate Student Theses & Dissertations

Power consumption becomes more and more critical in computer systems nowadays. Most of the previous work has been focusing on general-purpose computational core, but optimization techniques for conventional CPU core has reached a limit. Our experimental results show that read operations in SRAM can be performed at a lower supply with much reduced power consumption compared to write operations. Based on this observation and the fact that cache, consisting mostly of SRAM, often occupies significant on-chip area of the CPU and consumes a huge portion of the CPU power, we propose a new method to reduce the power consumption of …

Flexible Plasmonic Sensing Substrates And Their Application In Explosive Sensing, Justin Bae, Srikanth Singamaneni

McKelvey School of Engineering Graduate Student Theses & Dissertations

With an increasing use of improvised explosive devices in combat and terrorism, there is an urgent need for novel methods of trace explosive detection that can provide an inexpensive and effective solution. This study focuses on the development of such platform using flexible surface enhanced Raman scattering (SERS) substrates. Gold nanorods(AuNR) functionalized with peptides selective to explosive molecules, trinitrotoluene(TNT) and dinitrotoluene (DNT) were immobilized on various substrates to fabricate a flexible SERS substrate. The peptide conjugated AuNRs can detect TNT and DNT vapors, and the cysteamine conjugated nanorods could detect TNT in aqueous solution down to 100 nM.

Additionally, we …

Computations Of Flow Fields Of An Airfoil And A Wing With Gurney Flap In Ground Effect, Xuan Zhang

McKelvey School of Engineering Graduate Student Theses & Dissertations

High lift devices used in transport aircraft are complex multi-element wings with slats and flaps which are difficult to design and they incur high manufacturing and maintenance costs. Taking all requirements into consideration, for light aircrafts using Gurney Flap may offer a low cost, low maintenance solution for improving the aerodynamic performance of aircraft during take-off and landing. Gurney Flap, first invented by Dan Gurney, is a small tab projecting from the trailing edge of airfoil. Gurney Flap can increase the lift coefficient and decrease the angle of attack for zero lift. However, at low angle of attack, Gurney flap …

Particle Enrichment In Longitudinal Standing Bulk Acoustic Wave Microfluidics, Mingyang Cui

McKelvey School of Engineering Graduate Student Theses & Dissertations

Separation, isolation, and enrichment of targeted nano- and microparticles are critical to a variety of biomedical applications from clinical research (development of therapeutics and diagnostics) to fundamental investigations that require concentration of specific cells from culture, separation of target species from heterogenous mixtures, or controlled perturbation of cells and microorganisms to determine their response to stimuli. Numerous techniques are available for bench-scale and medical settings; however, these traditional approaches are often labor intensive, time-consuming, costly, and/or require modification of the target. Efficiency and specificity are also lacking. Recently, techniques that exploit the similar scales of microfluidic technologies and the intrinsic …

Understanding Deleted File Decay On Removable Media Using Differential Analysis, James H. Jones Jr, Anurag Srivastava, Josh Mosier, Connor Anderson, Seth Buenafe

Annual ADFSL Conference on Digital Forensics, Security and Law

Digital content created by picture recording devices is often stored internally on the source device, on either embedded or removable media. Such storage media is typically limited in capacity and meant primarily for interim storage of the most recent image files, and these devices are frequently configured to delete older files as necessary to make room for new files. When investigations involve such devices and media, it is sometimes these older deleted files that would be of interest. It is an established fact that deleted file content may persist in part or in its entirety after deletion, and identifying the …

Current Understanding And Future Research Directions At The Onset Of The Next Century Of Sintering Science And Technology, Rajendra K. Bordia, Suk-Joong L. Kang, Eugene A. Olevsky

Publications

Sintering and accompanying microstructural evolution is inarguably the most important step in the processing of ceramics and hard metals. In this process, an ensemble of particles is converted into a coherent object of controlled density and microstructure at an elevated temperature (but below the melting point) due to the thermodynamic tendency of the particle system to decrease its total surface and interfacial energy. Building on a long development history as a major technological process, sintering remains among the most viable methods of fabricating novel ceramics, including high surface area structures, nanopowder-based systems, and tailored structural and functional materials. Developing new …

Evaluation Of Floorpan Tearing And Cable Splices For Cable Barrier Systems, Scott K. Rosenbaugh, Jason A. Hartwell, Robert W. Bielenberg, Ronald K. Faller, James C. Holloway, Karla A. Lechtenberg

Nebraska Department of Transportation: Research Reports

This research effort consisted of two objectives related to components of a prototype cable barrier system. The first objective was to mitigate the potential for vehicle floorpan tearing by modifying the cable guardrail posts. A bogie vehicle was equipped with a simulated floorpan designed to replicate the height, thickness, and strength of the floorpan of a Kia Rio vehicle. Baseline testing demonstrated that the top of the Midwest Weak Post (MWP) would contact, and crease the simulated floorpan, which matched the damage observed in actual full-scale vehicle crash tests. Once the test setup provided the desired results, various post configurations …

A Handy Underwater Solution, Benjamin Murdoch, Matt Ricks, Ales Ball, Jacob Olson, Ethan Durrant, Connor Monson, Lars Watts, Mark Killpack

Journal of Undergraduate Research

Hod Lipson once asked an audience at TED, “Where are the robots?” We’ve been waiting for them a long time now and modern robotics still hasn’t caught up with our hopes and dreams. Through our research we hope to address one of the major topics in robotics: movement (or kinematics), and use this moment of exploration to build a new low cost robotic hand capable of use within the exciting realm of aquatics.

Thermally Stable Support For Improved Synthetic Fuel Catalysts, Mark Lindsay, Dr. William Hecker, Dr. Morris Argyle

Journal of Undergraduate Research

Fischer-Tropsch Synthesis (FTS) has attracted interest recently as large natural gas deposits have been discovered across the globe. FTS is a gas-to-liquid technology that produces fuels with far fewer sulfur or nitrogen impurities, making it an attractive cleaner alternative to petroleum fuels[1]. Cobalt is the preferred catalyst for FTS[2], but it must be supported to achieve optimal performance. Alumina and silica have been used independently as colbalt FTS supports[3-4], and in mixtures as supports for other processes, but mixed silica-alumina supports have not been studied for FTS applications[5]. The BYU Catalysis Lab has discovered a silica-alumina support (AlSi) with high …

Geogrid-Reinforcement’S Zone Of Influence, Shaun Hilton, W. Spencer Guthrie

Journal of Undergraduate Research

Geogrid is a polypropylene material manufactured with approximately 1-in. wide openings, called apertures. A triaxial geogrid configuration is illustrated in Figure 1. Geogrid reinforcement is typically positioned beneath and/or within an aggregate base layer in a pavement structure and is designed to prevent lateral spreading of the individual aggregate particles comprising that layer. Thus, inter-particle friction can be increased among the individual aggregate particles located above and potentially below the geogrid. When this occurs, the result is an increase in the stiffness of the aggregate base layer that leads to a greater load-carrying capacity of the pavement.

Nanostructured Dielectric Materials For High Energy Density Multi Layer Ceramic Capacitors, Fatih Dogan

Materials Science and Engineering Faculty Research & Creative Works

A high energy density multilayer ceramic capacitor, having at least two electrode layers and at least one substantially dense polycrystalline dielectric layer positioned therebetween. The at polycrystalline dielectric layer has an average grain size of less than about 300 nanometers, a particle size distribution of between about 150 nanometers and about 3 micrometers, and a maximum porosity of about 1 percent. The dielectric layer is selected from the group including TiO₂, BaTiO₃, Al₂O₃, ZrO₂, lead zirconium titanate, and combinations thereof and has a breakdown strength of at least about 1100 …

Source Anonymization Of Digital Images: A Counter–Forensic Attack On Prnu Based Source Identification Techniques, Prithviraj Sengupta, Venkata Udaya Sameer, Ruchira Naskar, Ezhil Kalaimannan

Annual ADFSL Conference on Digital Forensics, Security and Law

A lot of photographers and human rights advocates need to hide their identity while sharing their images on the internet. Hence, source–anonymization of digital images has become a critical issue in the present digital age. The current literature contains a number of digital forensic techniques for “source–identification” of digital images, one of the most efficient of them being Photo–Response Non–Uniformity (PRNU) sensor noise pattern based source detection. PRNU noise pattern being unique to every digital camera, such techniques prove to be highly robust way of source–identification. In this paper, we propose a counter–forensic technique to mislead this PRNU sensor noise …

Harnessing Predictive Models For Assisting Network Forensic Investigations Of Dns Tunnels, Irvin Homem, Panagiotis Papapetrou

Annual ADFSL Conference on Digital Forensics, Security and Law

In recent times, DNS tunneling techniques have been used for malicious purposes, however network security mechanisms struggle to detect them. Network forensic analysis has been proven effective, but is slow and effort intensive as Network Forensics Analysis Tools struggle to deal with undocumented or new network tunneling techniques. In this paper, we present a machine learning approach, based on feature subsets of network traffic evidence, to aid forensic analysis through automating the inference of protocols carried within DNS tunneling techniques. We explore four network protocols, namely, HTTP, HTTPS, FTP, and POP3. Three features are extracted from the DNS tunneled traffic: …

An Accidental Discovery Of Iot Botnets And A Method For Investigating Them With A Custom Lua Dissector, Max Gannon, Gary Warner, Arsh Arora

Annual ADFSL Conference on Digital Forensics, Security and Law

This paper presents a case study that occurred while observing peer-to-peer network communications on a botnet monitoring station and shares how tools were developed to discover what ultimately was identified as Mirai and many related IoT DDOS Botnets. The paper explains how researchers developed a customized protocol dissector in Wireshark using the Lua coding language, and how this enabled them to quickly identify new DDOS variants over a five month period of study.

2016 "Meeting Of The Minds" Research Symposium Abstracts

OSRI Journal of Student Research and Innovation

No abstract provided.

Artificial Islands In The South China Sea, Aaron Holmes

OSRI Journal of Student Research and Innovation

The purpose of this study was to understand the value and implications of artificial islands constructed by the People's Republic of China (PRC) in the South China Sea. Qualitative analysis was used with the available literature, sources, and treaties of the topics concerned. The paper concludes that the PRC gains many benefits primarily within the realm of energy security and explores what effects they may

The Face That Launched A Thousand Ships: Helen Of Troy In The Poetry Of Atwood And Tufts, Alea Walstrom

OSRI Journal of Student Research and Innovation

This paper considers the transformation of Greek myth over time, how character’s attributes change over time, and ultimately how contemporary poets employ these myths. The myth of focus in the paper is that of Helen of Troy and the depiction of her character throughout the many years and variations of the myth. Her character is then considered in the contemporary feminist poetry of Carol Tufts and Margaret Atwood.

Low Loss And Low Dispersion Fiber For Transmission Applications In The Terahertz Regime, Sohel Rana, Adnan Siraj Rakin, Harish Subbaraman, Rainer Leonhardt, Derek Abbott

Electrical and Computer Engineering Faculty Publications and Presentations

In this letter we present a novel slotted core fiber incorporating a slotted cladding for the terahertz band. The modal properties of the designed fiber are numerically investigated based on an efficient finite element method (FEM). Simulation results of the fiber exhibit both a low material absorption loss of 0.0103–0.0145 cm^-1 and low dispersion below 0.5 ps/THz/cm within the 0.5–0.9 THz range. Additionally, a number of other features of the fiber have been evaluated.

Sub 2 Nm Particle Characterization In Systems With Aerosol Formation And Growth, Yang Wang

McKelvey School of Engineering Graduate Student Theses & Dissertations

Aerosol science and technology enable continual advances in material synthesis and atmospheric pollutant control. Among these advances, one important frontier is characterizing the initial stages of particle formation by real time measurement of particles below 2 nm in size. Sub 2 nm particles play important roles by acting as seeds for particle growth, ultimately determining the final properties of the generated particles. Tailoring nanoparticle properties requires a thorough understanding and precise control of the particle formation processes, which in turn requires characterizing nanoparticle formation from the initial stages. The knowledge on particle formation in early stages can also be applied …

The Effect Of Diffusive Transport On Mineral Carbonation In Geologic Carbon Sequestration, Wei Xiong

McKelvey School of Engineering Graduate Student Theses & Dissertations

Geologic carbon sequestration (GCS) is an effective method to mitigate environmental problems due to excessive anthropogenic CO2 emissions. It involves injecting supercritical CO2 into deep geologic formations in which CO2 will ultimately be converted to solid carbonate minerals. Basalt is a promising host rock that is rich in the divalent cations Ca, Mg and Fe that are important for mineral trapping of CO2. Fractures and pores in basalt reservoirs provide substantial surface area for geochemical reactions during carbon sequestration. The transport in fractures and pores is controlled by diffusion. The coupling of diffusive transport and geochemical reactions leads to carbonate …

Pore Functionalized Pvdf Membranes With In-Situ Synthesized Metal Nanoparticles: Material Characterization, And Toxic Organic Degradation, Hongyi Wan, Nicolas J. Briot, Anthony Saad, Lindell E. Ormsbee, Dibakar Bhattacharyya

Chemical and Materials Engineering Faculty Publications

Functionalized PVDF membrane platforms were developed for environmentally benign in-situ nanostructured Fe/Pd synthesis and remediation of chlorinated organic compounds. To prevent leaching and aggregation, nanoparticle catalysts were integrated into membrane domains functionalized with poly (acrylic acid). Nanoparticles of 16–19 nm were observed inside the membrane pores by using focused ion beam (FIB). This technique prevents mechanical deformation of the membrane, compared to the normal SEM preparation methods, thus providing a clean, smooth surface for nanoparticles characterization. This allowed quantification of nanoparticle properties (size and distribution) versus depth underneath the membrane surface (0–20 μm). The results showed that nanoparticles were uniformly …

Anisotropy And Emission From Air With Laser Filaments, Mohammadamin Rasoulof

Optical Science and Engineering ETDs

Laser filaments are extremely interesting entities for their unique characteristics. The high intensity inside the laser filaments creates nonlinear effects that are useful in many areas of optics. The laser filamentation is an appealing tool in the stand-off spectroscopy for its ability to propagate over long distances while maintains its extreme intensity. However, depletion of energy hinders its propagation over any desired distance. In order to understand the effect of laser filaments on the transparent medium that they propagate through, one needs to investigate interaction of the laser filaments with the constituents of media. In this work we study the …

Pet/Mr Imaging Of Hypoxic Atherosclerotic Plaque Using 64cu-Atsm, Xingyu Nie

McKelvey School of Engineering Graduate Student Theses & Dissertations

ABSTRACT OF THE DISSERTATION

PET/MR Imaging of Hypoxic Atherosclerotic Plaque Using 64Cu-ATSM

by

Xingyu Nie

Doctor of Philosophy in Biomedical Engineering

Washington University in St. Louis, 2017

Professor Pamela K. Woodard, Chair

Professor Suzanne Lapi, Co-Chair

It is important to accurately identify the factors involved in the progression of atherosclerosis because advanced atherosclerotic lesions are prone to rupture, leading to disability or death. Hypoxic areas have been known to be present in human atherosclerotic lesions, and lesion progression is associated with the formation of lipid-loaded macrophages and increased local inflammation which are potential major factors in the formation of vulnerable …