Computer Engineering Commons^™

Heterogeneous Multi-Sensor Fusion For 2d And 3d Pose Estimation, Hanieh Deilamsalehy

Dissertations, Master's Theses and Master's Reports

Sensor fusion is a process in which data from different sensors is combined to acquire an output that cannot be obtained from individual sensors. This dissertation first considers a 2D image level real world problem from rail industry and proposes a novel solution using sensor fusion, then proceeds further to the more complicated 3D problem of multi sensor fusion for UAV pose estimation.

One of the most important safety-related tasks in the rail industry is an early detection of defective rolling stock components. Railway wheels and wheel bearings are two components prone to damage due to their interactions with the …

Using Lower Extremity Muscle Activations To Estimate Human Ankle Impedance In The External-Internal Direction, Lauren N. Knop

Dissertations, Master's Theses and Master's Reports

For millions of people, mobility has been afflicted by lower limb amputation. Lower extremity prostheses have been used to improve the mobility of an amputee; however, they often require additional compensation from other joints and do not allow for natural maneuverability. To improve upon the functionality of ankle-foot prostheses, it is necessary to understand the role of different muscle activations in the modulation of mechanical impedance of a healthy human ankle. This report presents the results of using artificial neural networks (ANN) to determine the functional relationship between lower extremity electromyography (EMG) signals and ankle impedance in the transverse plane. …

An Algorithm For Reconstructing Three-Dimensional Images From Overlapping Two-Dimensional Intensity Measurements With Relaxed Camera Positioning Requirements, With Application To Additive Manufacturing, Siranee Nuchitprasitchai

Dissertations, Master's Theses and Master's Reports

Cameras are everywhere for security purposes and there are often many cameras installed close to each other to cover areas of interest, such as airport passenger terminals. These systems are often designed to have overlapping fields of view to provide different aspects of the scene to review when, for example, law enforcement issues arise. However, these cameras are rarely, if ever positioned in a way that would be conducive to conventional stereo image processing. To address this, issue an algorithm was developed to rectify images measured under such conditions, and then perform stereo image reconstruction. The initial experiments described here …

Blossomsttm Hub – An Online Tool For Designing Sttm Vectors And Visualizing Phenotypic Changes Of Sttm Transgenic Lines, Avinash Subramanian

Dissertations, Master's Theses and Master's Reports

Small RNAs including microRNAs (miRNAs) and short interfering RNAs (siRNAs) are widely present in plants. They are transcribed from non-coding small RNA genes and then play as regulators to modulate the levels of messenger RNAs (mRNAs) of protein-coding genes via sequence pairings. This is because a paired complementary double sequence helix structure can trigger mRNA degradation or interfere with mRNA translation. Short Tandem Target Mimic (STTM) is a recently developed technology that can be used to produce a complementary sequence to a miRNA and destroy it or reduce the expression level of this miRNA via the formation of paired double-strand …

Guaranteed Rendezvous For Cognitive Radio Networks Based On Cycle Length, Li Gou

Dissertations, Master's Theses and Master's Reports

Rendezvous is a fundamental process establishing a communication link on common channel between a pair of nodes in the cognitive radio networks. How to reach rendezvous efficiently and effectively is still an open problem. In this work, we propose a guaranteed cycle lengths based rendezvous (CLR) algorithm for cognitive radio networks. When the cycle lengths of the two nodes are coprime, the rendezvous is guaranteed within one rendezvous period considering the time skew between the two nodes. When T_i and T_j are not coprime, i.e., T_i=T_j, the deadlock checking and node IDs are combined …

Evaluating Intention To Use Remote Robotics Experimentation In Programming Courses, Pericles Leng Cheng

Walden Dissertations and Doctoral Studies

The Digital Agenda for Europe (2015) states that there will be 825,000 unfilled vacancies for Information and Communications Technology by 2020. This lack of IT professionals stems from the small number of students graduating in computer science. To retain more students in the field, teachers can use remote robotic experiments to explain difficult concepts. This correlational study used the unified theory of acceptance and use of technology (UTAUT) to examine if performance expectancy, effort expectancy, social influence, and facilitating conditions can predict the intention of high school computer science teachers in Cyprus, to use remote robotic experiments in their classes. …

Improving Peptide Identification By Considering Ordered Amino Acid Usage, Ahmed Al-Qurri

Theses and Dissertations

Proteomics has made major progress in recent years after the sequencing of the genomes of a substantial number of organisms. A typical method for identifying peptides uses a database of peptides identified using tandem mass spectrometry (MS/MS). The profile of accurate mass and elution time (AMT) for peptides that need to be identified will be compared with this database. Restricting the search to those peptides detectable by MS will reduce processing time and more importantly increase accuracy. In addition, there are significant impacts for clinical studies. Proteotypic peptides are those peptides in a protein sequence that are most likely to …

Underwater Cave Mapping And Reconstruction Using Stereo Vision, Nicholas Weidner

Theses and Dissertations

This work presents a systematic approach for 3-D mapping and reconstruction of underwater caves. Exploration of underwater caves is very important for furthering our understanding of hydrogeology, managing efficiently water resources, and advancing our knowledge in marine archaeology. Underwater cave exploration by human divers however, is a tedious, labor intensive, extremely dangerous operation, and requires highly skilled people. As such, it is an excellent fit for robotic technology. The proposed solution employs a stereo camera and a video-light. The approach utilizes the intersection of the cone of video-light with the cave boundaries resulting in the construction of a wire frame …

Improving Facial Action Unit Recognition Using Convolutional Neural Networks, Shizhong Han

Theses and Dissertations

Recognizing facial action units (AUs) from spontaneous facial expression is a challenging problem, because of subtle facial appearance changes, free head movements, occlusions, and limited AU-coded training data. Most recently, convolutional neural networks (CNNs) have shown promise on facial AU recognition. However, CNNs are often overfitted and do not generalize well to unseen subject due to limited AU-coded training images. In order to improve the performance of facial AU recognition, we developed two novel CNN frameworks, by substituting the traditional decision layer and convolutional layer with the incremental boosting layer and adaptive convolutional layer respectively, to recognize the AUs from …

In-Situ Terahertz Optical Hall Effect Measurements Of Ambient Effects On Free Charge Carrier Properties Of Epitaxial Graphene, Sean Knight, Tino Hofmann, Chamseddine Bouhafs, Nerijus Armakavicius, Philipp Kühne, Vallery Stanishev, Ivan G. Ivanov, Rositsa Yakimova, Shawn Wimer, Mathias Schubert, Vanya Darakchieva

Department of Electrical and Computer Engineering: Faculty Publications

Unraveling the doping-related charge carrier scattering mechanisms in two-dimensional materials such as graphene is vital for limiting parasitic electrical conductivity losses in future electronic applications. While electric field doping is well understood, assessment of mobility and density as a function of chemical doping remained a challenge thus far. In this work, we investigate the effects of cyclically exposing epitaxial graphene to controlled inert gases and ambient humidity conditions, while measuring the Lorentz force-induced birefringence in graphene at Terahertz frequencies in magnetic fields. This technique, previously identified as the optical analogue of the electrical Hall effect, permits here measurement of charge …

Rainbow Peacock Spiders Inspire Miniature Superiridescent Optics, Bor-Kai Hsiung, Radwanul Hasan Siddique, Doekele G. Stavenga, Jürgen C. Otto, Michael C. Allen, Ying Liu, Yongfeng Lu, Dimitri D. Deheyn, Matthew D. Shawkey, Todd A. Blackledge

Department of Electrical and Computer Engineering: Faculty Publications

Colour produced by wavelength-dependent light scattering is a key component of visual communication in nature and acts particularly strongly in visual signalling by structurallycoloured animals during courtship. Two miniature peacock spiders (Maratus robinsoni and M. chrysomelas) court females using tiny structured scales (~ 40 × 10 μm²) that reflect the full visual spectrum. Using TEM and optical modelling, we show that the spiders’ scales have 2D nanogratings on microscale 3D convex surfaces with at least twice the resolving power of a conventional 2D diffraction grating of the same period. Whereas the long optical path lengths required …

Controllable Plasmonic Nanostructures Induced By Dual-Wavelength Femtosecond Laser Irradiation, Weina Han, Lan Jiang, Xiaowei Li, Qingsong Wang, Shaojun Wang, Jie Hu, Yongfeng Lu

Department of Electrical and Computer Engineering: Faculty Publications

We demonstrated an abnormal double-peak (annular shaped) energy deposition through dualwavelength synthesis of the fundamental frequency (ω) and the second-harmonic frequency (2ω) of a femtosecond (fs) Ti:sapphire laser. The annular shaped distribution of the dual-wavelength fs laser was confirmed through real beam shape detection. This uniquely simple and flexible technique enables the formation of functional plasmonic nanostructures. We applied this double-peak fs-laser-induced dewetting effect to the controlled fabrication and precise deposition of Au nanostructures, by using a simple, lithography-free, and single-step process. In this process, the double-peak energy-shaped fs laser pulse induces surface patterning of a thin film followed by …

Preparation Of Monolayer Mos2 Quantum Dots Using Temporally Shaped Femtosecond Laser Ablation Of Bulk Mos2 Targets In Water, Bo Li, Lan Jiang, Xin Li, Peng Ran, Pei Zuo, Andong Wang, Liangti Qu, Yang Zhao, Zhihua Cheng, Yongfeng Lu

Department of Electrical and Computer Engineering: Faculty Publications

Zero-dimensional MoS₂ quantum dots (QDs) possess distinct physical and chemical properties, which have garnered them considerable attention and facilitates their use in a broad range of applications. In this study, we prepared monolayer MoS₂ QDs using temporally shaped femtosecond laser ablation of bulk MoS₂ targets in water. The morphology, crystal structures, chemical, and optical properties of the MoS₂ QDs were characterized by transmission electron microscopy, X-ray diffraction, Raman spectroscopy, X-ray photoelectron spectroscopy, UV–vis absorption spectra, and photoluminescence spectra. The analysis results show that highly pure, uniform, and monolayer MoS₂ QDs can be successfully prepared. Moreover, …

Tunable Subnanometer Gap Plasmonic Metasurfaces, Dennis Doyle, Nicholas Charipar, Christos Argyropoulos, Scott A. Trammell, Rafaela Nita, Jawad Naciri, Alberto Piqué, Joseph B. Herzog, Jake Fontana

Department of Electrical and Computer Engineering: Faculty Publications

The index of refraction governs the flow of light through materials. At visible and near-infrared wavelengths the real part of the refractive index is limited to less than 3 for naturally occurring transparent materials, fundamentally restricting applications. Here, we carried out experiments to study the upper limit of the effective refractive index of self-assembled metasurfaces at visible and near-infrared wavelengths. The centimeter-scale metasurfaces were made of a hexagonally close packed (HCP) monolayer of gold nanospheres coated with tunable alkanethiol ligand shells, controlling the interparticle gap from 2.8 to 0.45 nm. In contrast to isolated dimer studies, the macroscale areas allow …

Flatland Plasmonics And Nanophotonics Based On Graphene And Beyond, Pai-Yen Chen, Christos Argyropoulos, Mohamed Farhat, J. Sebastian Gomez-Diaz

Department of Electrical and Computer Engineering: Faculty Publications

In this paper, we review and discuss how the recently discovered two-dimensional (2D) Dirac materials, particularly graphene, may be utilized as new efficient platforms for excitations of propagating and localized surface plasmon polaritons (SPPs) in the terahertz (THz) and mid-infrared (MIR) regions. The surface plasmon modes supported by the metallic 2D materials exhibit tunable plasmon resonances that are essential, yet missing, ingredients needed for THz and MIR photonic and optoelectronic devices. We describe how the atomically thin graphene monolayer and metamaterial structures based on it may tailor and control the spectral, spatial, and temporal properties of electromagnetic radiation. In the …

Higher C-Reactive Protein Levels Predict Postoperative Delirium In Older Patients Undergoing Major Elective Surgery: A Longitudinal Nested Case-Control Study, Simon T. Dillon, Sarinnapha M. Vasunilashorn, Long Ngo, Hasan H. Otu, Sharon K. Inouye, Richard N. Jones, David C. Alsop, George A. Kuchel, Eran D. Metzger, Steven E. Arnold, Edward R. Marcantonio, Towia A. Libermann

Department of Electrical and Computer Engineering: Faculty Publications

Background—Delirium is a common, morbid, and costly postoperative complication.. We aimed to identify blood-based postoperative delirium markers in a nested case control study of older surgical patients using a proteomics approach followed by enzyme-linked immunosorbent assay (ELISA) validation.

Methods and Materials—The Successful Aging after Elective Surgery Study enrolled dementia-free adults age ≥70 undergoing major scheduled non-cardiac surgery (N=566; 24% delirium). Plasma was collected at 4 timepoints: preoperatively (PREOP), post-anesthesia care unit (PACU), postoperative day 2 (POD2) and 1 month follow-up (PO1MO). Matched pairs were selected for the independent discovery (39 pairs) and replication cohorts (36 pairs), which were …

Formation Of Aggregated Nanoparticle Spheres Through Femtosecond Laser Surface Processing, Alfred T. Tsubaki, Mark A. Koten, Michael J. Lucis, Craig Zuhlke, Natale J. Ianno, Jeffrey E. Shield, Dennis R. Alexander

Department of Electrical and Computer Engineering: Faculty Publications

A detailed structural and chemical analysis of a class of self-organized surface structures, termed aggregated nanoparticle spheres (AN-spheres), created using femtosecond laser surface processing (FLSP) on silicon, silicon carbide, and aluminum is reported in this paper. AN-spheres are spherical microstructures that are 20–100 μm in diameter and are composed entirely of nanoparticles produced during femtosecond laser ablation of material. AN-spheres have an onion-like layered morphology resulting from the build-up of nanoparticle layers over multiple passes of the laser beam. The material properties and chemical composition of the AN-spheres are presented in this paper based on scanning electron microscopy (SEM), focused …

Direct Torque Control Of Ac Electric Machines, Wei Qiao, Zhe Zhang, Liyan Qu

Department of Electrical and Computer Engineering: Faculty Publications

This disclosure features an apparatus including a motor controller to generate control signals to control an electric motor. The motor controller includes a first saturation controller to generate a first saturation controller output based on feedback signals associated with the electric motor. The motor controller further includes a duty ratio modulator coupled to the first saturation controller. The duty ratio modulator is configured to determine activation times for a set of voltage vectors based on the first saturation controller output. The motor controller is configured to generate, at each switching cycle, a control signal based on the set of voltage …

Smart Underground Antenna Arrays: A Soil Moisture Adaptive Beamforming Approach, Abdul Salam, Mehmet C. Vuran

School of Computing: Technical Reports

In this paper, a novel framework for underground beamforming using adaptive antenna arrays is presented. Based on the analysis of propagation in wireless underground channel, a theoretical model is developed which uses soil moisture information and feedback mechanism to improve performance wireless underground communications. Array element in soil has been analyzed empirically and impacts of soil type and soil moisture on return loss and resonant frequency are investigated. Beam patterns are investigated to communicate with both underground and above ground devices. Depending on the incident angle, refraction from soil-air interface has the adverse effects in the UG communications. It is …

Wireless Underground Channel Diversity Reception With Multiple Antennas For Internet Of Underground Things, Abdul Salam, Mehmet C. Vuran

School of Computing: Conference and Workshop Papers

Internet of underground things (IOUT) is an emerging paradigm which consists of sensors and communication devices, partly or completely buried underground for real-time soil sensing and monitoring. In this paper, the performance of different modulation schemes in IOUT communications is studied through simulations and experiments. The spatial modularity of direct, lateral, and reflected components of the UG channel is exploited by using multiple antennas. First, it has been shown that bit error rates of $10^{-3}$ can be achieved with normalized delay spreads ($\tau_d$) lower than $0.05$. Evaluations are conducted through the first software-defined radio-based field experiments for UG channel. Moreover, …