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Near Earth Space Object Detection Using Parallax As Multi-Hypothesis Test Criterion, Joseph C. Tompkins, Stephen C. Cain, David J. Becker 2019 Air Force Institute of Technology

Near Earth Space Object Detection Using Parallax As Multi-Hypothesis Test Criterion, Joseph C. Tompkins, Stephen C. Cain, David J. Becker

Faculty Publications

The US Strategic Command (USSTRATCOM) operated Space Surveillance Network (SSN) is tasked with Space Situational Awareness (SSA) for the U.S. military. This system is made up of Electro-Optic sensors, such as the Ground-based Electro-Optical Deep Space Surveillance (GEODSS) and RADAR based sensors, such as the Space Fence Gaps. They remain in the tracking of Resident Space Objects (RSO’s) in Geosynchronous Orbits (GEO), due to limitations of SST and GEODSS system implementation. This research explores a reliable, ground-based technique used to quickly determine an RSO’s altitude from a single or limited set of observations. Implementation of such sensors into the SSN …


Experimental Study: Underwater Propagation Of Super-Gaussian And Multi-Gaussian Schell-Model Partially Coherent Beams With Varying Degrees Of Spatial Coherence, Svetlana Avramov-Zamurovic, Charles L. Nelson, Milo W. Hyde IV 2019 United States Naval Academy

Experimental Study: Underwater Propagation Of Super-Gaussian And Multi-Gaussian Schell-Model Partially Coherent Beams With Varying Degrees Of Spatial Coherence, Svetlana Avramov-Zamurovic, Charles L. Nelson, Milo W. Hyde Iv

Faculty Publications

We report on experiments where super-Gaussian and flat-top, multi-Gaussian Schell-model spatially partially coherent beams, with varying degrees of spatial coherence, were propagated underwater. Two scenarios were explored—calm and mechanically agitated water. The main objective of our study was the experimental comparison of the scintillation statistics. For a similar degree of coherence widths, the results show a potentially improved performance of scintillation index for the multi-Gaussian Schell-model beams as compared to the super-Gaussian beams. It should be noted that the presented results pertain only to the given experimental scenarios and further investigation is necessary to determine the scope of the findings.


Dynamic Light Scattering Optical Coherence Tomography To Probe Motion Of Subcellular Scatterers., Nico J J Arezza, Marjan Razani, Michael C Kolios 2019 Western University

Dynamic Light Scattering Optical Coherence Tomography To Probe Motion Of Subcellular Scatterers., Nico J J Arezza, Marjan Razani, Michael C Kolios

Medical Biophysics Publications

Optical coherence tomography (OCT) is used to provide anatomical information of biological systems but can also provide functional information by characterizing the motion of intracellular structures. Dynamic light scattering OCT was performed on intact, control MCF-7 breast cancer cells and cells either treated with paclitaxel to induce apoptosis or deprived of nutrients to induce oncosis. Autocorrelations (ACs) of the temporal fluctuations of OCT intensity signals demonstrate a significant decrease in decorrelation time after 24 h in both the paclitaxel-treated and nutrient-deprived cell groups but no significant differences between the two groups. The acquired ACs were then used as input for …


Deep-Turbulence Wavefront Sensing Using Digital Holography In The On-Axis Phase Shifting Recording Geometry With Comparisons To The Self-Referencing Interferometer, Douglas E. Thornton, Mark F. Spencer, Glen P. Perram 2019 Air Force Institute of Technology

Deep-Turbulence Wavefront Sensing Using Digital Holography In The On-Axis Phase Shifting Recording Geometry With Comparisons To The Self-Referencing Interferometer, Douglas E. Thornton, Mark F. Spencer, Glen P. Perram

Faculty Publications

In this paper, we study the use of digital holography in the on-axis phase-shifting recording geometry for the purposes of deep-turbulence wavefront sensing. In particular, we develop closed-form expressions for the field-estimated Strehl ratio and signal-to-noise ratio for three separate phase-shifting strategies—the four-, three-, and two-step methods. These closed-form expressions compare favorably with our detailed wave-optics simulations, which propagate a point-source beacon through deep-turbulence conditions, model digital holography with noise, and calculate the Monte Carlo averages associated with increasing turbulence strengths and decreasing focal-plane array sampling. Overall, the results show the four-step method is the most efficient phase-shifting strategy and …


Control Of Light-Matter Interactions Via Nanostructured Photonic Materials, Nicholas Proscia 2019 CUNY Graduate Center

Control Of Light-Matter Interactions Via Nanostructured Photonic Materials, Nicholas Proscia

Dissertations, Theses, and Capstone Projects

The thesis here investigates the manipulation of light-matter interactions via nanoscale engineering of material systems. When material systems are structured on the nanoscale, their optical responses can be dramatically altered. In this thesis, this is done in two primary ways: One method is by changing the geometry of nanostructures to induce a resonant behavior with incident electromagnetic field of optical wavelengths. This allows field enhancement in highly localized areas to strengthen exotic light-matter interactions that would otherwise be too weak to measure or for practical use. In this regard, the work presented here studies a voltage produced in a metal …


Control Of Energy Transfer And Molecular Energetics Using Photonic Nanostructures, Rahul Deshmukh 2019 CUNY Graduate Center

Control Of Energy Transfer And Molecular Energetics Using Photonic Nanostructures, Rahul Deshmukh

Dissertations, Theses, and Capstone Projects

In the last three decades, the design and fabrication of different types of photonic nanostructures have allowed us to control and enhance the interaction of light (or photons) with matter (or excitons). In this work, we demonstrate the use of three different nanostructures to control different material properties. The design and fabrication of the nanostructures is discussed along with the results obtained using characterization techniques of angle-resolved white light reflectivity and transmission, and time-resolved and steady-state photoluminescence experiments. Specifically, we demonstrate the use of Optical Topological Transitions (OTT) in metamaterials to show enhanced efficiency in the non-radiative transfer of energy …


Hybrid Optical Integrator Based On Silicon-On-Insulator Platform, Taewon Huh 2019 Rose-Hulman Institute of Technology

Hybrid Optical Integrator Based On Silicon-On-Insulator Platform, Taewon Huh

Graduate Theses - Physics and Optical Engineering

A hybrid optical integrator is a recirculating loop that performs oversampling typically for analog input, using the cross-gain modulation (XGM) in a semiconductor optical amplifier (SOA). The modulated input signal changes the gain of the loop through XGM and thus modifies the loop accumulation. This thesis presents hybrid optical integrator for an all-optical analog-to-digital converter based on a silicon photonics platform. The device consists of silicon waveguides of dimension 220 × 500 nm (thick × width) and approximately 5 m optical loop length including fiber length, input and output grating couplers for 1550 nm signal, directional couplers, and external components …


In-Fiber Temperature Sensor Based On Green Up-Conversion Luminescence In An Er3+-Yb3+ Co-Doped Tellurite Glass Microsphere, Meng Zhang, Angzhen Li, Jibo Yu, Xiaosong Lu, Shunbin Wang, Elfed Lewis, Gerald Farrell, Libo Yuan, Pengfei Wang 2019 Harbin Engineering University

In-Fiber Temperature Sensor Based On Green Up-Conversion Luminescence In An Er3+-Yb3+ Co-Doped Tellurite Glass Microsphere, Meng Zhang, Angzhen Li, Jibo Yu, Xiaosong Lu, Shunbin Wang, Elfed Lewis, Gerald Farrell, Libo Yuan, Pengfei Wang

Articles

A novel, to the best of our knowledge, in-fiber temperature sensor based on green up-conversion (UC) luminescence in an Er3+-Yb3+" role="presentation" style="box-sizing: border-box; display: inline; font-size: 12.88px; line-height: normal; word-spacing: normal; overflow-wrap: normal; white-space: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; position: relative;">Er3+-Yb3+Er3+-Yb3+ co-doped tellurite glass microsphere is described. The tellurite glass microsphere is located firmly inside a suspended tri-core hollow-fiber (STCHF) structure. The pump light launched via a single-mode fiber (SMF) is passed through a section of multimode fiber, which is fusion spliced between the SMF …


Theoretical Analysis Of A Volume Holographic Lens Using Matlab, Sanjay Keshri, Kevin Murphy, Izabela Naydenova, Suzanne Martin 2019 Technological University Dublin

Theoretical Analysis Of A Volume Holographic Lens Using Matlab, Sanjay Keshri, Kevin Murphy, Izabela Naydenova, Suzanne Martin

Conference Papers

Volume holographic lenses have great potential for different types of applications requiring light redirection and beam shaping such as solar light collection and LED light management. For lighting applications using LEDs, it is essential to make a highly efficient optical element to be placed in front of the LED in order to decrease energy losses. For that reason, a careful theoretical analysis of the properties and operation regime of the lens must be carried out at the design stage. The characteristics of focusing Holographic Optical Elements (HOE) depend on many factors including their thickness, spatial frequency, the angular range of …


Ultrabroadband Mid-Infrared Emission From Cr 2+ -Doped Infrared Transparent Chalcogenide Glass Ceramics Embedded With Thermally Grown Zns Nanorods, Xiaosong Lu, Zhiqiang Lai, Runan Zhang, Haitao Guo, Jing Ren, Lukas Strizik, Tomas Wagner, Gerald Farrell, Pengfei Wang 2019 Harbin Engineering University

Ultrabroadband Mid-Infrared Emission From Cr 2+ -Doped Infrared Transparent Chalcogenide Glass Ceramics Embedded With Thermally Grown Zns Nanorods, Xiaosong Lu, Zhiqiang Lai, Runan Zhang, Haitao Guo, Jing Ren, Lukas Strizik, Tomas Wagner, Gerald Farrell, Pengfei Wang

Articles

We report, for the first time to our knowledge, an ultrabroadband mid-infrared (MIR) emission in the range of 1800–2800 nm at room temperature from a Cr2+-doped chalcogenide glass ceramic embedded with pure hexagonal (wurtzite) β-ZnS nanorods and study the emission-dependent properties on the doping concentration of Cr2+. A new family of chalcogenide glasses based on (100 − x) Ge1.5As2S6.5 – x ZnSe (in mol.%) was prepared by melt-quenching method. The Cr2+: β-ZnS nanorods of ˜150 nm in diameter and ˜1 μm in length were grown in the Cr2+-doped glass after thermal annealing. The compositional variations of glass structures and optical …


Fundamental Properties Of Metallic Nanolasers, William Hayenga 2019 University of Central Florida

Fundamental Properties Of Metallic Nanolasers, William Hayenga

Electronic Theses and Dissertations

The last two decades have witnessed tremendous advancements in the area of nanophotonics and plasmonics, which has helped propel the development of integrated photonic sources. Of central importance to such circuits is compact, scalable, low threshold, and efficient coherent sources that can be driven at high modulation frequencies. In this regard, metallic nanolasers offer a unique platform. Their introduction has enabled confinement of light at a subwavelength scale and the ultra-small size of the modes afforded by these structures allows for cavity enhancing effects that can help facilitate thresholdless lasing and large direct modulation bandwidths. In this report, I present …


Processing Of Advanced Infrared Materials, Daniel Mcgill 2019 University of Central Florida

Processing Of Advanced Infrared Materials, Daniel Mcgill

Electronic Theses and Dissertations

Infrared transparent glassy and crystalline materials often have unique and complex processing requirements but are an important class of materials for such applications as optical windows, lenses, waveplates, polarizers and beam splitters. This thesis investigates two specific materials, one amorphous and one crystalline, that are candidates for use in the short and midwave-infrared and mid and longwave infrared, respectively. It is demonstrated that an innovative uniaxial sintering process, which uses a sacrificial pressure-transmitting medium, can be used to fully densify a 70TeO2-20WO3-10La2O3 (TWL) glass powder. The characteristics of the sintered TWL glass is compared to that of a parent glass …


Development Of Uv Led Based Lamps With Modular Optical Heads, Ciara O'Hara 2019 CAPPA, Cork Institute of Technology, Cork.

Development Of Uv Led Based Lamps With Modular Optical Heads, Ciara O'Hara

Theses

This project was centred around the development of the optical components, and the optimisation of the optical performance, of ProPhotonix Ltd’s Cobra Cure FX series of products. These are high irradiance, high dose, UVA (primarily 395 nm and 365 nm) Light Emitting Diode (LED) lamps designed for curing applications. An initial prototype developed by ProPhotonix, the smallest in the series, the FX1, underwent significant redesign throughout the project, and the two larger lamps, the FX2 and the FX3 were developed during the course of the project. This work primarily consisted in characterising, accurately modelling, and thereby refining, the optical reflector …


Active Recall Networks For Multiperspectivity Learning Through Shared Latent Space Optimization, Theus Aspiras, Ruixu Liu, Vijayan K. Asari 2019 University of Dayton

Active Recall Networks For Multiperspectivity Learning Through Shared Latent Space Optimization, Theus Aspiras, Ruixu Liu, Vijayan K. Asari

Electrical and Computer Engineering Faculty Publications

Given that there are numerous amounts of unlabeled data available for usage in training neural networks, it is desirable to implement a neural network architecture and training paradigm to maximize the ability of the latent space representation. Through multiple perspectives of the latent space using adversarial learning and autoencoding, data requirements can be reduced, which improves learning ability across domains. The entire goal of the proposed work is not to train exhaustively, but to train with multiperspectivity. We propose a new neural network architecture called Active Recall Network (ARN) for learning with less labels by optimizing the latent space. This …


Magnetic Field Sensor Based On A Tri-Microfiber Coupler Ring In Magnetic Fluid And A Fiber Bragg Grating, Fangfang Wei, Dejun Liu, Arun Kumar Mallik, Gerald Farrell, Qiang Wu, Gang-ding Peng, Yuliya Semenova 2019 Technological University Dublin

Magnetic Field Sensor Based On A Tri-Microfiber Coupler Ring In Magnetic Fluid And A Fiber Bragg Grating, Fangfang Wei, Dejun Liu, Arun Kumar Mallik, Gerald Farrell, Qiang Wu, Gang-Ding Peng, Yuliya Semenova

Articles

In this paper we propose and investigate a novel magnetic field sensor based on a Tri-microfiber coupler combined with magnetic fluid and a fiber Bragg grating (FBG) in a ring. A sensitivity of 1306 pm/mT was experimentally demonstrated in the range of magnetic fields from 0 to 15 mT. The reflection peak in the output spectrum associated with the FBG serves as a reference point allowing to avoid ambiguity in determining the spectral shift induced by the magnetic field. Due to its high sensitivity at low magnetic fields, the proposed structure could be of high interest in low field biosensing …


Deep Temporal Convolutional Networks For Short-Term Traffic Flow Forecasting, Wentian Zhao, Yanyun Gao, Tingxiang Ji, Xili Wan, Feng Ye, Guangwei Bai 2019 Nanjing Tech University

Deep Temporal Convolutional Networks For Short-Term Traffic Flow Forecasting, Wentian Zhao, Yanyun Gao, Tingxiang Ji, Xili Wan, Feng Ye, Guangwei Bai

Electrical and Computer Engineering Faculty Publications

To reduce the increasingly congestion in cities, it is essential for intelligent transportation system (ITS) to accurately forecast the short-term traffic flow to identify the potential congestion sites. In recent years, the emerging deep learning method has been introduced to design traffic flow predictors, such as recurrent neural network (RNN) and long short-term memory (LSTM), which has demonstrated its promising results. In this paper, different from existing work, we study the temporal convolutional network (TCN) and propose a deep learning framework based on TCN model for short-term city-wide traffic forecast to accurately capture the temporal and spatial evolution of traffic …


A Twelve-Wavelength Thulium-Doped Fibre Laser Based On A Microfibre Coil Resonator Incorporating Black Phosphorus, Shi Li, Yu Yin, Elfed Lewis, Gerald Farrell, Pengfei Wang 2019 Harbin Engineering University

A Twelve-Wavelength Thulium-Doped Fibre Laser Based On A Microfibre Coil Resonator Incorporating Black Phosphorus, Shi Li, Yu Yin, Elfed Lewis, Gerald Farrell, Pengfei Wang

Articles

A novel multi-wavelength continuous Thulium-doped fibre laser incorporating a microfibre coil resonator based on black phosphorus (MCR-BP) material has been successfully fabricated and demonstrated. A twelve-wavelength spectrum with 0.54 nm channel spacing has been achieved by simply adjusting the pump source power. A single peak extinction ratio of more than 40 dB was observed. The superior performance of the MCR-BP described in this article compared to conventional MCR based fibre lasers can be attributed the inclusion of the Black Phosphorous Material. The enhanced lasing is primarily due to the twin properties of the MCR-BP device combining a comb-like filter effect …


Mode Transition In Conventional Step-Index Optical Fibers, Xiaokang Lian, Gerald Farrell, Qiang Wu, Wei Han, Fangfang Wei, Yuliya Semenova 2019 Technological University Dublin

Mode Transition In Conventional Step-Index Optical Fibers, Xiaokang Lian, Gerald Farrell, Qiang Wu, Wei Han, Fangfang Wei, Yuliya Semenova

Conference Papers

The discrete self-imaging effect reveals the distinct properties of cladding modes with core modes in step-index optical fibers, as was shown in our previous work [1], where only the linearly polarized LP0n modes were studied. In this paper, the dispersion diagram of the first 17 vector modes (TE0n, TM0n, HEmn and EHmn) and the related first 9 LPmn modes are calculated by both the full-vector finite element method and the graphical method with a three-layer step-index optical fiber model. The cladding modes distributions and the transitions between the core and cladding modes are analyzed. The results of this work are …


Mode Coupling In Space-Division Multiplexed Systems, Huiyuan Liu 2019 University of Central Florida

Mode Coupling In Space-Division Multiplexed Systems, Huiyuan Liu

Electronic Theses and Dissertations

Even though fiber-optic communication systems have been engineered to nearly approach the Shannon capacity limit, they still cannot meet the exponentially-growing bandwidth demand of the Internet. Space-division multiplexing (SDM) has attracted considerable attention in recent years due to its potential to address this capacity crunch. In SDM, the transmission channels support more than one spatial mode, each of which can provide the same capacity as a single-mode fiber. To make SDM practical, crosstalk among modes must be effectively managed. This dissertation presents three techniques for crosstalk management for SDM. In some cases such as intra-datacenter interconnects, even though mode crosstalk …


High Performance Liquid Crystal Devices For Augmented Reality And Virtual Reality, Md Javed Rouf Talukder 2019 University of Central Florida

High Performance Liquid Crystal Devices For Augmented Reality And Virtual Reality, Md Javed Rouf Talukder

Electronic Theses and Dissertations

See-through augmented reality and virtual reality displays are emerging due to their widespread applications in education, engineering design, medical, retail, transportation, automotive, aerospace, gaming, and entertainment. For augmented reality and virtual reality displays, high-resolution density, high luminance, fast response time and high ambient contrast ratio are critically needed. High-resolution density helps eliminate the screen-door effect, high luminance and fast response time enable low duty ratio operation, which plays a key role for suppressing image blurs. A dimmer placed in front of AR display helps to control the incident background light, which in turn improves the image contrast. In this dissertation, …


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