Engineering Commons^™

Experimental Study Of The Flow Of Ferrofluid In A Porous Media Under A Magnetic Field, Muskaan Khurana

Dissertations, Master's Theses and Master's Reports

This research presents results from a laboratory-scale experimental setup that was designed to visualize the behavior of ferrofluid percolation through a porous media. Ferrofluids are colloidal suspensions made of magnetic particles of a few nanometers and stabilized in carrier liquids like water or mineral oil. Ferrofluids get magnetized and align themselves in the direction of a magnetic field when a field gradient is applied.

With the help of this experiment we investigate the viability of controlling fluid flow in porous medium by a magnetic field in vicinity. The experiments show that ferrofluids can be used as a transporting media to …

Autonomous Dc Microgrid With Self-Configurable Feasibility, Amir Farshad

Dissertations, Master's Theses and Master's Reports

Microgrids are power systems that work not only from the main power grid, but also in island mode operation. As each of the power sources and loads have voltage and current limitations, the autonomous microgrid should be able to control voltage and current levels while loads and sources are connected to the grid. Therefore, the microgrid bus voltage remains constant and power transfers safely.

To configure an autonomous microgrid, the load and source type identification comes to mind. An autonomous microgrid needs to know the type of the electrical components which are going to be connected to the grid. In …

Finite Element Analysis And Topology Optimization Of Differential Case And Control Arm For Static And Fatigue Loading, Pankaj N. Kalan

Dissertations, Master's Theses and Master's Reports

Optimization of the automobile components can result in a significant decrease in vehicle weight, increase in fuel efficiency and reduction in environmental damage. For example, the lightweight vehicle production will save over 4.4×109 GJ of energy and 4.1×108 tons of CO2 over a 10 year period, compared to the current non-light weight vehicles. This equates to 890 billion miles or 42 billion gallons of gas savings (Wu 2016). This study evaluates the weight reduction possible by using manual and automatic (using Optistruct software) topology optimization processes. Optimization of a vehicle differential case done in this study shows that a weight …

Design And Development Of Optical Elastography Setup, Abhinav Madhavachandran

Dissertations, Master's Theses and Master's Reports

The mechanical properties of the skin are an indication of its physiological condition. The properties can serve as potential information for dermatologists for diagnosis and qualitative assessment. Elastography is a medical imaging modality developed to extract the elastic properties of a tissue by application of an external force. Optical elastography is a technique of elastography which uses laser speckle tracking to study the elastic properties of several soft tissue including skin.

This work is aimed at developing an optical elastography setup that can study the elastic properties of skin. The setup includes an imaging system and a force-application system controlled …

Competition Vehicle Based Intake Manifold Design, Joshua N. Matiash

Dissertations, Master's Theses and Master's Reports

A competitive vehicle in Formula SAE needs to be easy for unskilled drivers to extract the maximum performance from. This requires a predictable and manageable torque curve. This report details the development of an intake manifold for a Formula SAE car from a vehicle-based approach to produce this manageable and predictable torque. The current vehicle was instrumented and driven on a representative track to determine the usage of available torque. Based on these findings an ideal torque curve was chosen that favored increased torque at upper engine speed ranges and decreased torque at lower engine speed ranges. A 1-D engine …

Small Size Coupling Feed And Inductive Shorting Antenna For Wide Bandwidth, Increased Gain And Efficiency With Low Specific Absorption Rate (Sar) Operation, Md Mahfuzur Rahman

Dissertations, Master's Theses and Master's Reports

Day by day technology is changing our lives rapidly. With these radical changes, demands in communication industry are also increasing drastically. To cope up with these demands, 2G, 3G, 4G, LTE (Long Term Evolution) communication systems have been introduced. Modern cellular phone should be capable to operate in wide range of frequency spectrum for their global access to provide end user customers these communication services. Hence mobile antennas should be designed in such a way that they should generate wideband operation. But commercially available standalone mobile antennas aren’t capable to operate in all those communication systems, several antennas are used …

Purification And Recovery Of Infectious Virus Particles Using Osmolyte Flocculation, Ashish Saksule

Dissertations, Master's Theses and Master's Reports

Viral infectious diseases cause millions of deaths and severe illness all around the world affecting public health and economics. Viral vaccines are helping to fight against viral diseases, but current vaccines are expensive and unavailable, especially in poor and developing countries. When measuring the entire manufacturing processing, the downstream processing of vaccines is the major cost of production. Our goal for this research is to develop a low-cost alternative downstream processing platform for new vaccine manufacturing infrastructures. We have developed a novel osmolyte flocculation method for viral particles. To create a platform purification for several types of viral particles, we …

A Novel Hierarchical Bag-Of-Words Model For Compact Action Representation, Qianru Sun, Qianru, Hong Liu, Hong Liu, Liqian Ma, Tianwei Zhang

Research Collection School Of Computing and Information Systems

Bag-of-Words (BOW) histogram of local space-time features is very popular for action representation due to its high compactness and robustness. However, its discriminant ability is limited since it only depends on the occurrence statistics of local features. Alternative models such as Vector of Locally Aggregated Descriptors (VLAD) and Fisher Vectors (FV) include more information by aggregating high-dimensional residual vectors, but they suffer from the problem of high dimensionality for final representation. To solve this problem, we novelly propose to compress residual vectors into low-dimensional residual histograms by the simple but efficient BoW quantization. To compensate the information loss of this …

Iot+Small Data: Transforming In-Store Shopping Analytics And Services, Meera Radhakrishnan, Sougata Sen, Vigneshwaran Subbaraju, Archan Misra, Rajesh Balan

Research Collection School Of Computing and Information Systems

We espouse a vision of small data-based immersive retail analytics, where a combination of sensor data, from personal wearable-devices and store-deployed sensors & IoT devices, is used to create real-time, individualized services for in-store shoppers. Key challenges include (a) appropriate joint mining of sensor & wearable data to capture a shopper’s product level interactions, and (b) judicious triggering of power-hungry wearable sensors (e.g., camera) to capture only relevant portions of a shopper’s in-store activities. To explore the feasibility of our vision, we conducted experiments with 5 smartwatch-wearing users who interacted with objects placed on cupboard racks in our lab (to …

Analyses Of 476 Mhz And 952 Mhz Crab Cavities For Jlab Electron Ion Collider, Hyekyoung Park, A. Castilla, J. R. Delayen, S. U. De Silva, V. Morozov

Physics Faculty Publications

Center for Accelerator Science at ODU has designed, fabricated and successfully tested a crab cavity for MEIC at Jefferson Lab*. This proof of principle cavity was based on the earlier MEIC design which used 748.5 MHz RF system. The updated MEIC design** utilizes the components from PEP-II. It results in the change on the bunch repetition rate of stored beam to 476.3 MHz. The ion ring collider will eventually require 952.6 MHz crab cavity. This paper will present the analyses of crab cavities of both 476 MHz and 952 MHz options. It compares advantages and disadvantages of the options which …

Investing In Least Developed Countries: The Aynak Mine Project, Roosevelt Barfield

Walden Dissertations and Doctoral Studies

The rise of market globalization creates challenges for business executives seeking to pursue foreign direct investment (FDI) in least developed countries (LDC), such as Afghanistan. Multinational corporate (MNC) executives need strategies that will improve the timely delivery of minerals for mining projects in LDCs. Guided by the force field analysis theory, the purpose of this holistic, single-case study was to explore the strategies that 5 MNC executives in Beijing, China, used to improve the timely delivery of minerals associated with the Aynak copper mine project in Afghanistan. Semistructured interviews were used to elicit detailed narratives from MNC executives about their …

Wireless Channel Modeling For Networks On Chips, William Rayess

Theses and Dissertations

The advent of integrated circuit (chip) multiprocessors (CMPs) combined with the continuous reduction in device physical size (technology scaling) to the sub-nanometer regime will result in an exponential increase in the number of processing cores that can be integrated within a single chip. Today’s CMPs already support tens to low hundreds of cores and both industry and academic roadmaps project that future chips will have thousands of cores. Therefore, while there are open questions on how to harness the computing power offered by CMPs, the design of power-efficient and compact on-chip interconnection networks that connects cores, caches and memory controllers …

Urban Resilience: The Regeneration Of The Dublin Docklands, Aoife Doyle

Conference papers

Resilience, and more specifically ‘urban resilience’, is a ‘fuzzy’ concept, which has gained increasing public, political and academic interest over the past two decades; particularly in the context of the global financial crisis of the late 2000s. This paper adopts an understanding of resilience as the ability of cities to change, adapt and, crucially, transform in response to stresses and strains. Yet how have cities – and urban planning – responded to the recent economic crisis; and how can one examine this in practice? This paper investigates the case of Dublin, Ireland. In particular, it utilises the resilience concept to …

Anisotropy, Band-To-Band Transitions, Phonon Modes, And Oxidation Properties Of Cobalt-Oxide Core-Shell Slanted Columnar Thin Films, Alyssa Mock, Rafał Korlacki, Chad Briley, Derek Sekora, Tino Hofmann, Peter Wilson, Alexander Sinitskii, Eva Schubert, Mathias Schubert

Department of Electrical and Computer Engineering: Faculty Publications

Highly ordered and spatially coherent cobalt slanted columnar thin films (SCTFs) were deposited by glancing angle deposition onto silicon substrates, and subsequently oxidized by annealing at 475˚C. Scanning electron microscopy, Raman scattering, generalized ellipsometry, and density functional theory investigations reveal shape-invariant transformation of the slanted nanocolumns from metallic to transparent metal-oxide core-shell structures with properties characteristic of spinel cobalt oxide. We find passivation of Co-SCTFs yielding Co-Al₂O₃ core-shell structures produced by conformal deposition of a few nanometers of alumina using atomic layer deposition fully prevents cobalt oxidation in ambient and from annealing up to 475˚C.

A Survey Of Wireless Communication Technologies & Their Performance For High Speed Railways, Subharthi Banerjee, Michael Hempel, Hamid Sharif

Department of Electrical and Computer Engineering: Faculty Publications

High Speed Railway (HSR) provides its customers not only safety, security, comfort and on-time commuting, but also a fast transportation alternative to air travel or regular passenger rail services. Providing these benefits would not be possible without the tremendous growth and prevalence of wireless communication technologies. Due to advances in wireless communication systems, both trains and passengers are connected through high speed wireless networks to the Internet, data centers and railroad control centers. Railroad communities, academia, related industries and standards bodies, even the European Space Agency, are involved in advancing developments of HSR for highly connected train communication systems. The …

Detecting Microbial Dysbiosis Associated With Pediatric Crohn Disease Despite The High Variability Of The Gut Microbiota, Feng Wang, Jess L. Kaplan, Benjamin D. Gold, Manoj K. Bhasin, Naomi L. Ward, Richard Kellermayer, Barbara S. Kirschner, Melvin B. Heyman, Scot E. Dowd, Stephen B. Cox, Haluk Dogan, Blaire Steven, George Ferry, Stanley A. Cohen, Robert N. Baldassano, Christopher J. Moran, Elizabeth A. Garnett, Lauren Drake, Hasan H. Otu, Leonid A. Mirny, Towia A. Libermann, Harland S. Winter, Kirill S. Korolev

Department of Electrical and Computer Engineering: Faculty Publications

The relationship between the host and its microbiota is challenging to understand because both microbial communities and their environments are highly variable. We have developed a set of techniques based on population dynamics and information theory to address this challenge. These methods identify additional bacterial taxa associated with pediatric Crohn disease and can detect significant changes in microbial communities with fewer samples than previous statistical approaches required. We have also substantially improved the accuracy of the diagnosis based on the microbiota from stool samples, and we found that the ecological niche of a microbe predicts its role in Crohn disease. …

Sticking With The Pointy End? Molecular Configuration Of Chloro Boron-Subphthalocyanine On Cu(111), Nahid Ilyas, Shashank S. Harivyasi, Percy Zahl, Rocio Cortes, Oliver T. Hofmann, Peter Sutter, Egbert Zojer, Oliver L. A. Monti

Department of Electrical and Computer Engineering: Faculty Publications

In this combined low-temperature scanning tunneling microscopy (STM) and density functional theory (DFT) study, we investigate self-assembly of the dipolar nonplanar organic semiconductor chloro boron-subphthalocyanine (ClB-SubPc) on Cu(111). We observe multiple distinct adsorption configurations and demonstrate that these can only be understood by taking surface-catalyzed dechlorination into account. A detailed investigation of possible adsorption configurations and the comparison of experimental and computational STM images demonstrates that the configurations correspond to “Cl-up” molecules with the B− Cl moiety pointing toward the vacuum side of the interface, and dechlorinated molecules. In contrast to the standard interpretation of adsorption of nonplanar molecules in …

Hybrid Quantum Dot-Tin Disulfide Field-Effect Transistors With Improved Photocurrent And Spectral Responsivity, Yuan Huang, Huidong Zang, Jia -Shiang Chen, Eli Sutter, Peter Sutter, Chang- Yong Nam, Mircea Cotlet

Department of Electrical and Computer Engineering: Faculty Publications

We report an improved photosensitivity in few-layer tin disulfide (SnS2) field-effect transistors (FETs) following doping with CdSe/ZnS core/shell quantum dots (QDs). The hybrid QD-SnS₂ FET devices achieve more than 500% increase in the photocurrent response compared with the starting SnS₂-only FET device and a spectral responsivity reaching over 650 A/W at 400 nm wavelength. The negligible electrical conductance in a control QD-only FET device suggests that the energy transfer between QDs and SnS₂ is the main mechanism responsible for the sensitization effect, which is consistent with the strong spectral overlap between QD photoluminescence and SnS_{2 …}

Broadband Compact Microstrip Patch Antenna Design Loaded By Multiple Split Ring Resonator Superstrate And Substrate, Shobhit K. Patel, Christos Argyropoulos, Yogeshwar P. Kosta

Department of Electrical and Computer Engineering: Faculty Publications

We present microstrip patch antenna loaded with multiple split ring resonator substrate and superstrate. We analyze how the loading of split ring resonator superstrate and substrate can improve the bandwidth compared to the simple microstrip patch antenna and microstrip patch antenna loaded with split ring resonator superstrate. Another important observation is made for multiple split ring resonator loading in superstrate and substrate of microstrip patch antenna. The design is compared for two, three, and four-ring split ring resonator loading. The designs are also compared for different gap spacing between the rings. All three designs are compared for small gap and …

Meta-Analysis Of Transcriptome Data Identifies A Novel 5-Gene Pancreatic Adenocarcinoma Classifier, Manoj K. Bhasin, Kenneth Ndebele, Octavian Bucur, Eric U. Yee, Hasan H. Otu, Jessica Plati, Andrea Bullock, Xuesong Gu, Eduardo Castan, Peng Zhang, Robert Najarian, Maria S. Muraru, Rebecca Miksad, Roya Khosravi-Far, Towia A. Libermann

Department of Electrical and Computer Engineering: Faculty Publications

Purpose: Pancreatic ductal adenocarcinoma (PDAC) is largely incurable due to late diagnosis. Superior early detection biomarkers are critical to improving PDAC survival and risk stratification.

Experimental Design: Optimized meta-analysis of PDAC transcriptome datasets identified and validated key PDAC biomarkers. PDAC-specific expression of a 5-gene biomarker panel was measured by qRT-PCR in microdissected patient-derived FFPE tissues. Cell-based assays assessed impact of two of these biomarkers, TMPRSS4 and ECT2, on PDAC cells.

Results: A 5-gene PDAC classifier (TMPRSS4, AHNAK2, POSTN, ECT2, SERPINB5) achieved on average 95% sensitivity and 89% specificity in discriminating PDAC from non-tumor samples in four training sets and similar …

Coordinate-Invariant Lyddane-Sachs-Teller Relationship For Polar Vibrations In Materials With Monoclinic And Triclinic Crystal Systems, Mathias Schubert

Department of Electrical and Computer Engineering: Faculty Publications

A coordinate-invariant generalization of the Lyddane-Sachs-Teller relation is presented for polar vibrations in materials with monoclinic and triclinic crystal systems. The generalization is derived from an eigendielectric displacement vector summation approach, which is equivalent to the microscopic Born-Huang description of polar lattice vibrations in the harmonic approximation. An expression for a general oscillator strength is also described for materials with monoclinic and triclinic crystal systems. A generalized factorized form of the dielectric response characteristic for monoclinic and triclinic materials is proposed. The generalized Lyddane-Sachs-Teller relation is found valid for monoclinic β-Ga2O3, where accurate experimental data became available recently from a …

Dst Approach To Enhance Audio Quality On Lost Audio Packet Steganography, Qilin Qi, Dongming Peng, Hamid Sharif

Department of Electrical and Computer Engineering: Faculty Publications

Lost audio packet steganography (LACK) is a steganography technique established on the VoIP network. LACK provides a high-capacity covert channel over VoIP network by artificially delaying and dropping a number of packets in use to convey stegnogram. However, the increasing loss of packets will hurt the quality of the VoIP service. The quality deterioration will not only affect the legitimate VoIP service but also constrain the capacity of the covert channel. Discrete spring transform (DST) is proven to be a way to eliminate the perceptual redundancy in the multimedia signal. In this paper, the DST is applied on the LACK …

Embeddable Advanced Sensors For Harsh Environment Sensing Applications, Lei Yuan, Yinan Zhang, Yan Lu, Xiaobei Zhang, Mengmeng Wang

Department of Electrical and Computer Engineering: Faculty Publications

Research and development in advanced sensors with embedded monitoring capability have experienced significant growth in recent years, fueled by their broad applications in real-time measurement of a wide variety of physical, chemical, and biological quantities. Compared with conventional sensors with bulky assemblies, recent progress in 3D manufacturing technologies (e.g., ultrafast laser micromachining and additive manufacturing) has opened up a new avenue in one-step fabrication of assembly-freemicro devices in various materials as well as the development of compact, customized, and intricate smart structures/components. The merits of these advanced manufacturing techniques enable the integration of embeddable advanced sensors into smart structures and …

A Wideband And Polarization-Independent Metasurface Based On Phase Optimization For Monostatic And Bistatic Radar Cross Section Reduction, Jianxun Su, Yao Lu, Zengrui Li, Rongrong Zhang, Yaoqing (Lamar) Yang

Department of Electrical and Computer Engineering: Faculty Publications

A broadband and polarization-independent metasurface is analyzed and designed for both monostatic and bistatic radar cross section (RCS) reduction in this paper. Metasurfaces are composed of two types of electromagnetic band-gap (EBG) lattice, which is a subarray with “0” or “𝜋” phase responses, arranged in periodic and aperiodic fashions. A new mechanism is proposed for manipulating electromagnetic (EM) scattering and realizing the best reduction of monostatic and bistatic RCS by redirecting EM energy to more directions through controlling the wavefront of EMwave reflected from the metasurface. Scattering characteristics of two kinds of metasurfaces, periodic arrangement and optimized phase layout, are …

Anisotropy, Phonon Modes, And Free Charge Carrier Parameters In Monoclinic Β-Gallium Oxide Single Crystals, Mathias Schubert, Rafal Korlacki, Sean Knight, Tino Hofmann, Stefan Schöche, Vanya Darakchieva, Erik Janzén, Bo Monemar, Daniela Gogova, Q.-T. Thieu, R. Togashi, H. Murakami, Yoshinao Kumagai, Ken Goto, Akito Kuramata, S. Yamakoshi, Masataka Higashiwaki

Department of Electrical and Computer Engineering: Faculty Publications

We derive a dielectric function tensor model approach to render the optical response of monoclinic and triclinic symmetry materials with multiple uncoupled infrared and far-infrared active modes. We apply our model approach to monoclinic β-Ga₂O₃ single-crystal samples. Surfaces cut under different angles from a bulk crystal, (010) and (2̅01), are investigated by generalized spectroscopic ellipsometry within infrared and far-infrared spectral regions. We determine the frequency dependence of 4 independent β-Ga₂O₃ Cartesian dielectric function tensor elements by matching large sets of experimental data using a point-by-point data inversion approach. From matching our monoclinic …

Early Life History Of Three Pelagic-Spawning Minnows Macrhybopsis Spp. In The Lower Missouri River, T. A. Starks, M. L. Miller, J. M. Long

United States Army Corps of Engineers, Omaha District

Life-history characteristics of age-0 sturgeon chub Macrhybopsis gelida, shoal chub Macrhybopsis hyostoma and sicklefin chub Macrhybopsis meeki were compared using several methods. All Macrhybopsis species consumed mostly midge pupae, but M. meeki had the most general diet (Levins’ index, B=0⋅22) compared with M. hyostoma (B=0⋅02) and M. gelida (B=0⋅09). Morisita’s diet overlap index among species pairs ranged from 0⋅62 to 0⋅97 and was highest between M. hyostoma and M. gelida. Daily ages estimated from lapilli otoliths for each species ranged from 15 to 43 days for M. gelida, 19 to 44 for …

A Shipboard Instrument For Underway Estimates Of Marine N2 Fixation, Weiyi Tang

Link Foundation Ocean Engineering and Instrumentation Fellowship Reports

Marine N2 fixation converts nitrogen gas into ammonia and accounts for the largest external nitrogen input to the oceans1. Since large portions of the global oceans are nitrogen deficient, marine N2 fixation can relieve the nitrogen limitation, thereby increasing the growth of phytoplankton and stimulating biological uptake of atmospheric carbon dioxide2,3,4. However, the magnitude and distribution of marine N2 fixation are poorly constrained5. In addition, the environmental controls on marine N2 fixation remain elusive6. This situation is in part attributable to the limited number of observations and poor coverage of marine N2 fixation measurements. Current observations rely on discrete sampling …

A Scalable Low-Cost Cgmp Process For Clinical Grade Production Of The Hiv Inhibitor 5p12-Rantes In Pichia Pastoris, Fabrice Cerini, Hubert Gaertner, Knut Madden, Ilya Tolstorukov, Scott Brown, Bram Laukens, Nico Callewaert, Jay C. Harner, Anna M. Oommen, John T. Harms, Anthony R. Sump, Robert C. Sealock, Dustin J. Peterson, Scott K. Johnson, Stephan B. Abramson, Michael M. Meagher, Robin Offord, Oliver Hartley

Department of Chemical and Biomolecular Engineering: Faculty Publications

In the continued absence of an effective anti-HIV vaccine, approximately 2 million new HIV infections occur every year, with over 95% of these in developing countries. Calls have been made for the development of anti-HIV drugs that can be formulated for topical use to prevent HIV transmission during sexual intercourse. Because these drugs are principally destined for use in low-resource regions, achieving production costs that are as low as possible is an absolute requirement. 5P12-RANTES, an analog of the human chemokine protein RANTES/CCL5, is a highly potent HIV entry inhibitor which acts by achieving potent blockade of the principal HIV …

Retargeting The Clostridium Botulinum C2 Toxin To The Neuronal Cytosol, Benjamin J. Pavlik, Elizabeth J. Hruska, Kevin E. Van Cott, Paul H. Blum

Department of Chemical and Biomolecular Engineering: Faculty Publications

Many biological toxins are known to attack specific cell types, delivering their enzymatic payloads to the cytosol. This process can be manipulated by molecular engineering of chimeric toxins. Using toxins with naturally unlinked components as a starting point is advantageous because it allows for the development of payloads separately from the binding/translocation components. Here the Clostridium botulinum C2 binding/translocation domain was retargeted to neural cell populations by deleting its non-specific binding domain and replacing it with a C. botulinum neurotoxin binding domain. This fusion protein was used to deliver fluorescently labeled payloads to Neuro-2a cells. Intracellular delivery was quantified by …

A Nocsae Drop Test/ 3d-Fem Study On The Relationship Between Kinematic Response Of The Head, Head Impact Contact Pressure (Hicp) And Kinetic Response Of The Brain To Delineate The Risk Of Traumatic Brain Injuries (Tbi)., Raghavendra Krishna Tej Bhamidipati

Dissertations, Master's Theses and Master's Reports

How many times have you seen a person slip and fall down and had a good laugh about it? How many times we slip and fall down on the floor and got up and walked away thinking everything is normal? Probably we might wonder “Are drops which occur at a small height dangerous?” Yes, they can be. Brain injuries are main reason for the fatality in youth [1], and low level falls are one of the most neglected and understated injuries.

The main objective of this study is to study the response of the brain for low level falls from …