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2020

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Articles 14881 - 14910 of 15205

Full-Text Articles in Physical Sciences and Mathematics

Local Binary Pattern Based Algorithms For The Discrimination And Detection Of Crops And Weeds With Similar Morphologies, Vi Nguyen Thanh Le Jan 2020

Local Binary Pattern Based Algorithms For The Discrimination And Detection Of Crops And Weeds With Similar Morphologies, Vi Nguyen Thanh Le

Theses: Doctorates and Masters

In cultivated agricultural fields, weeds are unwanted species that compete with the crop plants for nutrients, water, sunlight and soil, thus constraining their growth. Applying new real-time weed detection and spraying technologies to agriculture would enhance current farming practices, leading to higher crop yields and lower production costs. Various weed detection methods have been developed for Site-Specific Weed Management (SSWM) aimed at maximising the crop yield through efficient control of weeds. Blanket application of herbicide chemicals is currently the most popular weed eradication practice in weed management and weed invasion. However, the excessive use of herbicides has a detrimental impact …

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A Robust Hyperviscosity Formulation For Stable Rbf-Fd Discretizations Of Advection-Diffusion-Reaction Equations On Manifolds, Varun Shankar, Grady B. Wright, Akil Narayan Jan 2020

A Robust Hyperviscosity Formulation For Stable Rbf-Fd Discretizations Of Advection-Diffusion-Reaction Equations On Manifolds, Varun Shankar, Grady B. Wright, Akil Narayan

Mathematics Faculty Publications and Presentations

We present a new hyperviscosity formulation for stabilizing radial basis function-finite difference (RBF-FD) discretizations of advection-diffusion-reaction equations on manifolds �� ⊂ ℝ3 of codimension 1. Our technique involves automatic addition of artificial hyperviscosity to damp out spurious modes in the differentiation matrices corresponding to surface gradients, in the process overcoming a technical limitation of a recently developed Euclidean formulation. Like the Euclidean formulation, the manifold formulation relies on von Neumann stability analysis performed on auxiliary differential operators that mimic the spurious solution growth induced by RBF-FD differentiation matrices. We demonstrate high-order convergence rates on problems involving surface advection and …

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Mapping And Modeling The Seattle Fault Tsunami Inundation In Puget Sound, David Bruce Jan 2020

Mapping And Modeling The Seattle Fault Tsunami Inundation In Puget Sound, David Bruce

All Master's Theses

Coastal communities of Puget Sound are susceptible to tsunami inundation from multiple sources. Two sources of potential tsunami hazard that threaten the region are earthquakes on crustal faults in the Puget Lowlands, or earthquakes originating on the Cascadia subduction zone. This study investigated two coastal marshes in Puget Sound, Deer Lagoon and Doe-Kag-Wats, for evidence of a paleotsunami record to combine with tsunami modeling, in order to predict how future events could inundate Puget Sound. A deposit, interpreted as a paleotsunami, is traceable thought the marsh stratigraphy near the modern day tidal inlet of Deer Lagoon, a site that has …

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Applying Garnet And Zircon Ree Linkages To Determine Timing Of P-T Conditions And Tectonic Implications For Uhp Eclogites And Hp Granulites, Dulan Uhp Terrane, China, Wesley Weisberg Jan 2020

Applying Garnet And Zircon Ree Linkages To Determine Timing Of P-T Conditions And Tectonic Implications For Uhp Eclogites And Hp Granulites, Dulan Uhp Terrane, China, Wesley Weisberg

All Master's Theses

The Dulan ultrahigh-pressure (UHP) terrane in western China hosts rocks that record continental collision, however; the timing of peak P-T conditions in UHP eclogites and HP granulites, and the tectonic significance of their spatial relationship within the Dulan UHP terrane are not well understood. This study, (1) evaluates rare earth element (REE) equilibrium between garnet and zircon, to assess coeval growth; (2) links timing (from zircon) to the P-T history (from garnet) to constrain the P-T-t path of the Dulan UHP terrane and interpret implications for zircon growth; (3) refines P-T conditions for HP granulite; and (4) evaluates the tectonic …

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The Role Of Cumulate Plagioclase Entrainment In The Steens Basalt, Se Oregon: Insights From The Magma Chamber Simulator, Valerie Strasser Jan 2020

The Role Of Cumulate Plagioclase Entrainment In The Steens Basalt, Se Oregon: Insights From The Magma Chamber Simulator, Valerie Strasser

All Master's Theses

The Steens Basalt, located in SE Oregon, is the oldest and most mafic member of the Columbia River Basalt Group (CRBG). Because the Steens Basalt contains large (up to 6 cm) and abundant (up to 40%) plagioclase crystals, it is classified as a Giant Plagioclase basalt (GPB). Understanding the origin of these giant plagioclase yields insight into magmatic processes like recharge, crustal assimilation, cumulate entrainment, and fractional crystallization. Because large and abundant plagioclase are found in other flood basalt provinces worldwide, these results could also enhance understanding of magma evolution and storage conditions for GPB worldwide. The Steens basalt is …

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Unravelling The Aggregation Of Eosin Y Photosensitisers For Solar Energy Conversion, Huw Richards Jan 2020

Unravelling The Aggregation Of Eosin Y Photosensitisers For Solar Energy Conversion, Huw Richards

Dissertations, Theses, and Masters Projects

The impact of molecular aggregation on the photophysics of eosin y adsorbed to TiO2 was investigated using diffuse reflectance spectroscopy, steady-state fluorescence and time correlated single photon counting (TCSPC) measurements. Deconvolution of the diffuse reflectance spectra of eosin y on TiO2 revealed the formation of H-aggregates, with the extent of H-aggregation increasing with increasing dye-loading concentration. The resultant bathochromic shift from the monomer diffuse reflectance maximum is due to Charge-transfermediated H-aggregates The fluorescent maximum also shifts with increasing dye loading concentration starting at 537.5 nm at a dye loading concentration of 7.5x10-7 M and shifting to 585 …

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Single Image Direct-Global Illumination Separation, Zhaoliang Duan Jan 2020

Single Image Direct-Global Illumination Separation, Zhaoliang Duan

Dissertations, Theses, and Masters Projects

Global light transport, including diffuse interreflections, caustic, refractions and subsurface scattering, is important to achieve photorealistic rendering. However rendering these phenomena is very time-consuming. Furthermore, many inverse rendering methods’ accuracy in computer graphics and computer vision is adversely affected by the presence of global light transport. Therefore, separating direct-global light transport components is necessary to help in designing new rendering methods and in improving the accuracy of many image inverse methods. Prior work on separating direct and global light transport from photographs either requires expensive hardware, requires multiple photographs of the scene, or fails to accurately recover high frequency details. …

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An Integrated Feasibility Study Of Reservoir Thermal Energy Storage (Rtes) In Portland, Or, Usa, John Bershaw, Alison E. Horst, Ashley Streig, Darby Patrick Scanlon, Ellen Elizabeth Svadlenak, Jenny Liu, Peter Hulseman, Ray E. Wells, Multiple Additional Authors Jan 2020

An Integrated Feasibility Study Of Reservoir Thermal Energy Storage (Rtes) In Portland, Or, Usa, John Bershaw, Alison E. Horst, Ashley Streig, Darby Patrick Scanlon, Ellen Elizabeth Svadlenak, Jenny Liu, Peter Hulseman, Ray E. Wells, Multiple Additional Authors

Geology Faculty Publications and Presentations

In regions with long cold overcast winters and sunny summers, Deep Direct-Use (DDU) can be coupled with Reservoir Thermal Energy Storage (RTES) technology to take advantage of pre-existing subsurface permeability to save summer heat for later use during cold seasons. Many aquifers worldwide are underlain by permeable regions (reservoirs) containing brackish or saline groundwater that has limited beneficial use due to poor water quality. We investigate the utility of these relatively deep, slow flowing reservoirs for RTES by conducting an integrated feasibility study in the Portland Basin, Oregon, USA, developing methods and obtaining results that can be widely applied to …

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Northward Migration Of The Oregon Forearc On The Gales Creek Fault, Ray E. Wells, Richard J. Blakely, Sean Bemis Jan 2020

Northward Migration Of The Oregon Forearc On The Gales Creek Fault, Ray E. Wells, Richard J. Blakely, Sean Bemis

Geology Faculty Publications and Presentations

The Gales Creek fault (GCF) is a 60-km-long, northwest-striking dextral fault system (west of Portland, Oregon) that accommodates northward motion and uplift of the Oregon Coast Range. New geologic mapping and geophysical models confirm inferred offsets from earlier geophysical surveys and document ∼12 km of right-lateral offset of a basement high in Eocene Siletz River Volcanics since ca. 35 Ma and ∼8.8 km of right-lateral separation of Miocene Columbia River Basalt at Newberg, Oregon, since 15 Ma (∼0.62 ± 0.12 mm/yr, average long-term rate). Relative uplift of Eocene Coast Range basalt basement west of the fault zone is at least …

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Geologic Map Of The Greater Portland Metropolitan Area And Surrounding Region, Oregon And Washington, Ray E. Wells, Ralph Haugerud, Alan Niem, Wendy A. Niem, Russell Evarts, J. E. O’Connor, Ian Madin, Marvin Beeson, Multiple Additional Authors Jan 2020

Geologic Map Of The Greater Portland Metropolitan Area And Surrounding Region, Oregon And Washington, Ray E. Wells, Ralph Haugerud, Alan Niem, Wendy A. Niem, Russell Evarts, J. E. O’Connor, Ian Madin, Marvin Beeson, Multiple Additional Authors

Geology Faculty Publications and Presentations

This geologic map encompasses the greater Portland metropolitan area (the metro area), an urbanized region astride the confluence of the Willamette and Columbia Rivers in Oregon and Washington. The metro area includes the Portland-VancouverHillsboro metropolitan area, defined by the U.S. Census as the 23rd largest such area in the U.S., having a population of more than 2.2 million people (https://www.census.gov/dataviz/visualizations/026/508.php). The map area extends beyond the urbanized core to include outlying towns and cities and the bounding fault zones that separate the metro area from the adjacent Coast Range and Cascade Range (or Cascades; figs. 1, 2, and 3). The …

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The Seasonal Evolution Of Albedo Across Glaciers And The Surrounding Landscape Of Taylor Valley, Antarctica, Anna Bergstrom, Michael N. Gooseff, Peter T. Doran, Julian M. Cross Jan 2020

The Seasonal Evolution Of Albedo Across Glaciers And The Surrounding Landscape Of Taylor Valley, Antarctica, Anna Bergstrom, Michael N. Gooseff, Peter T. Doran, Julian M. Cross

Geology Faculty Publications and Presentations

The McMurdo Dry Valleys (MDVs) of Antarctica are a polar desert ecosystem consisting of alpine glaciers, ice-covered lakes, streams, and expanses of vegetation-free rocky soil. Because average summer temperatures are close to 0 Cel., the MDV ecosystem in general, and glacier melt dynamics in particular, are both closely linked to the energy balance. A slight increase in incoming radiation or change in albedo can have large effects on the timing and volume of meltwater. However, the seasonal evolution or spatial variability of albedo in the valleys has yet to fully characterized. In this study, we aim to understand the drivers …

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Performing The Digital Self: Understanding Location-Based Social Networking, Territory, Space, And Identity In The City, Konstantinos Papangelis, Alan Chamberlain, Ioanna Lykourentzou, Vassilis-Javed Khan, Michael Saker, Hai-Ning Liang, Irwyn Sadien, Ting Cao Jan 2020

Performing The Digital Self: Understanding Location-Based Social Networking, Territory, Space, And Identity In The City, Konstantinos Papangelis, Alan Chamberlain, Ioanna Lykourentzou, Vassilis-Javed Khan, Michael Saker, Hai-Ning Liang, Irwyn Sadien, Ting Cao

Articles

Expressions of territoriality have been positioned as one of the main reasons users alter their behaviors and perceptions of spatiality and sociality while engaging with location-based social networks (LBSN). Despite the potential for this interplay to further our understanding of LBSN usage in the context of identity, very little work has actually been done towards this. Addressing this gap in the literature is one the chief aims of the article. Drawing on an original six-week study with 42 participants utilizing a bespoke LBSN entitled ‘GeoMoments’, our research explores: (1) the way that territoriality is linked to self-identity; and (2) how …

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The Power Of A Profound Experience With Nature, Becky N. Mathers Jan 2020

The Power Of A Profound Experience With Nature, Becky N. Mathers

Antioch University Dissertations & Theses

This dissertation explores the long-term influences of a profound experience with nature—an experience that shifts an individual’s view of or relationship with the natural world. Significant life experience research investigates the associations between formative experiences in nature and resulting environmental concern and action, including both singular events and repeated experiences. In the case of a single, memorable experience with nature, little is known about the long-term effects of these experiences or how individuals use the associated memories in their lives. This research investigates these questions through semi-structured interviews with twenty-one adults who had a profound experience with nature, exploring how …

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Using Environmental Identity To Promote Environmental Concern And Willingness To Participate In Endangered Species Conservation, Christina M. Wesolek Jan 2020

Using Environmental Identity To Promote Environmental Concern And Willingness To Participate In Endangered Species Conservation, Christina M. Wesolek

Antioch University Dissertations & Theses

Environmental identity (EID), a concept from the social sciences specifically conservation psychology, refers to how we orient ourselves to the natural world, and thereby take action based on our personality, values, and sense of self. The realization that conservation is a human endeavor has prompted the inclusion of the social sciences in conservation research. Research on environmental identity has been conducted in such places as zoos, higher education institutions, and with farmers, and has demonstrated that EID is a good predictor of environmental concern and proenvironmental behaviors. There is a gap in the literature regarding whether environmental identity can be …

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A Pedagogy Of Hope: Levers Of Change In Transformative Place-Based Learning Systems, Michelle G. Heaton Jan 2020

A Pedagogy Of Hope: Levers Of Change In Transformative Place-Based Learning Systems, Michelle G. Heaton

Antioch University Dissertations & Theses

In response to mounting wicked environmental problems and an outdated U.S. educational system, this dissertation investigates transformative place-based education as an adaptive boundary system that connects individual learning to positive social-ecological change. The research approaches learning through a systems lens through a novel framework of Social-ecological Systems, Place-based Education, and Transformative Learning Theories. A three-part mixed methods approach, including content analysis of the literature, phenomenological interviews with experts in place-based education, and fuzzy-logic cognitive mapping with educators at three schools practicing the principles of place-based education, is used to examine transformative place-based education from the perspectives of current U.S. place-based …

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Developing An Odonate-Based Index For Monitoring Freshwater Ecosystems In Rwanda: Towards Linking Policy To Practice Through Integrated And Adaptive Management, Erasme Uyizeye Jan 2020

Developing An Odonate-Based Index For Monitoring Freshwater Ecosystems In Rwanda: Towards Linking Policy To Practice Through Integrated And Adaptive Management, Erasme Uyizeye

Antioch University Dissertations & Theses

Worldwide, the decline of biodiversity in freshwater ecosystems is occurring at an alarming rate, due to anthropogenic threats, which directly impact humans in a variety of ways. Freshwater ecosystems occupy an integral part of political, socio-economic and ecological spheres. Integrated Watershed Management (IWM) and Adaptive Management (AM) conceptual frameworks provide an underpinning holistic platform from which to evaluate the performance of policies and actions on the ground in relation to freshwater ecosystem management. I investigate the extent to which environmental policies and practices embrace IWM and AM frameworks in Rwanda. Furthermore, this dissertation develops an odonate-based ecological monitoring tool, referred …

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The Human Dimensions And Spatial Ecology Of Poaching And Implications For Red Wolf Survival, Suzanne Agan Jan 2020

The Human Dimensions And Spatial Ecology Of Poaching And Implications For Red Wolf Survival, Suzanne Agan

Antioch University Dissertations & Theses

In the 1970’s, red wolves were considered America’s most endangered mammalian species and the US Fish and Wildlife Service (USFWS) developed the Red Wolf Recovery Plan soon after passage of the Endangered Species Act (ESA) to preserve and eventually reintroduce them. It marked the first successful attempt to reintroduce a large predator that had been completely extirpated from the wild. The conservation of predators, such as red wolves, stirs controversy when it hinders human activities and some people retaliate by illegal killing. In Northeastern North Carolina (NENC), poaching has been a problem throughout the entire recovery process and is the …

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Using Blockchain For Digital Card Game, Raymond A. Swannack Jan 2020

Using Blockchain For Digital Card Game, Raymond A. Swannack

EWU Masters Thesis Collection

In recent years, the popularity of both online card games and blockchain technology have grown exponentially. While combining these two does not immediately seem like an obvious idea, they in fact complement each other nicely. Blockchain allows for players to actually own their cards, in a way that was unheard of in the digital format just a few years ago. It also gives them the freedom to use them in any way they like, just like in real life. In this thesis we will look into how viable this idea really is. We use the Ethereum virtual machine to simulate …

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Comparison Of Wetland Restoration Techniques In And Around Turnbull National Wildlife Refuge, Cheney, Wa, Jade S. Clinkenbeard Jan 2020

Comparison Of Wetland Restoration Techniques In And Around Turnbull National Wildlife Refuge, Cheney, Wa, Jade S. Clinkenbeard

EWU Masters Thesis Collection

Throughout the West, wetlands have been drained or filled in for agricultural or urban uses. Staff at Turnbull National Wildlife Refuge (TNWR) in Cheney work with local landowners to restore wetlands through excavation or flooding techniques. Unfortunately, TNWR staff cannot evaluate the wetlands to determine which technique is most successful. This thesis project compared the macroinvertebrate and plant communities and the limnological features of wetlands restored through excavation and flooding with those of unaltered, reference wetlands on TNWR. I hypothesized that the reference wetlands would hold water longest and would have higher plant diversity and macroinvertebrate diversity and abundance than …

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Attainment Of Rigorous Thermodynamic Consistency And Surface Tension In Single-Component Pseudopotential Lattice Boltzmann Models Via A Customized Equation Of State, Cheng Peng, Luis F. Ayala, Zhicheng Wang, Orlando M. Ayala Jan 2020

Attainment Of Rigorous Thermodynamic Consistency And Surface Tension In Single-Component Pseudopotential Lattice Boltzmann Models Via A Customized Equation Of State, Cheng Peng, Luis F. Ayala, Zhicheng Wang, Orlando M. Ayala

Engineering Technology Faculty Publications

The lack of thermodynamic consistency is a well-recognized problem in the single-component pseudopotential lattice Boltzmann models which prevents them from replicating accurate liquid and vapor phase densities; i.e., current models remain unable to exactly match coexisting density values predicted by the associated thermodynamic model. Most of the previous efforts had attempted to solve this problem by introducing tuning parameters, whose determination required empirical trial and error until acceptable thermodynamic consistency was achieved. In this study, we show that the problem can be alternatively solved by properly designing customized equations of state (EOSs) that replace any cubic EOS of choice during …

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Interpretive Geologic Maps And Cross Sections For Phelps, Kearney, And Adams Counties In Nebraska, Dana Divine, Leslie M. Howard Jan 2020

Interpretive Geologic Maps And Cross Sections For Phelps, Kearney, And Adams Counties In Nebraska, Dana Divine, Leslie M. Howard

Conservation and Survey Division

Data from thousands of test-hole and well logs were interpreted to improve understanding and management of the High Plains aquifer in a three-county study area adjacent to the Big Bend reach of the Platte River. Five principal conclusions resulted from these interpretations: (1) the extent of Neogene Ogallala deposits beneath the study area is different than previously mapped; (2) a large paleovalley incised into Cretaceous bedrock probably cuts across Kearney and Adams counties and may be the course of the ancestral Platte River prior to formation of the Big Bend; (3) a groundwater mound created by irrigation canals artificially raises …

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2019 Nebraska Water Leaders Academy Final Report, M.E. Burbach, R.M. Joeckel, G.S. Matkin Jan 2020

2019 Nebraska Water Leaders Academy Final Report, M.E. Burbach, R.M. Joeckel, G.S. Matkin

Conservation and Survey Division

No abstract provided.

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Correlating The Plant Height Of Wheat With Above-Ground Biomass And Crop Yield Using Drone Imagery And Crop Surface Model, A Case Study From Nepal, U. S. Panday, Nawaraj Shrestha, S. Maharjan, A. K. Pratihast, Shahnawaz, K. L. Shrestha, J. Aryal Jan 2020

Correlating The Plant Height Of Wheat With Above-Ground Biomass And Crop Yield Using Drone Imagery And Crop Surface Model, A Case Study From Nepal, U. S. Panday, Nawaraj Shrestha, S. Maharjan, A. K. Pratihast, Shahnawaz, K. L. Shrestha, J. Aryal

Conservation and Survey Division

No abstract provided.

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Experimental And Numerical Investigations Of Granular Dynamics In Microgravity, Stephanie Jarmak Jan 2020

Experimental And Numerical Investigations Of Granular Dynamics In Microgravity, Stephanie Jarmak

Electronic Theses and Dissertations, 2020-2023

During the first stages of planet formation small particles (~0.1 – 1 µm) in the protoplanetary disk collide at low relative velocities (less than 1 m/s) and tend to aggregate into cm-size "pebbles" through a combination of electrostatic interactions and gravitational streaming instabilities. Particles in this size regime also compose a layer of regolith on small, airless bodies that evolves under conditions very different than those on Earth. Characterizing the response of regolith to low-energy impacts in a microgravity environment is therefore critical to our understanding of the processes that lead to the formation of these objects and our ability …

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Multi-Parameter Optical Metrology: Quantum And Classical, Walker Larson Jan 2020

Multi-Parameter Optical Metrology: Quantum And Classical, Walker Larson

Electronic Theses and Dissertations, 2020-2023

The insights offered by quantum mechanics to the field of optical metrology are many-fold, with non-classical states of light themselves used to make sensors that surpass the sensitivity of sensors using classical states of light. Unfortunately, this advantage, referred to often as "super-sensitivity" is notoriously fragile, and even the slightest experimental imperfections may greatly reduce the efficacy of the non-classical sensors, sometimes completely obviating their advantage. In my thesis I have shown that the performance of an otherwise ideal two-photon interferometer, which exploits entanglement between photons to make super-sensitive measurements of phase, is crippled by the slightest introduction of decoherence …

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Design Of Ternary Operations Utilizing Flow-Based Computing, James Pyrich Jan 2020

Design Of Ternary Operations Utilizing Flow-Based Computing, James Pyrich

Electronic Theses and Dissertations, 2020-2023

The development of algorithms and circuit designs that exploit devices that have the ability to persist multiple values will lead to alternative technologies to overcome the issues caused by the end of Dennard scaling and slowing of Moore's Law. Flow-based designs have been used to develop binary adders and multipliers. Data stored on non-volatile memristors are used to direct the flow of current through nanowires arranged in a crossbar. The algorithmic design of the flow-based crossbar is fast, compact, and efficient. In this paper, we seek to automate the discovery of flow-based designs of ternary circuits utilizing memristive crossbars.

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Fluorescence Microscopy With Tailored Illumination Light, Jialei Tang Jan 2020

Fluorescence Microscopy With Tailored Illumination Light, Jialei Tang

Electronic Theses and Dissertations, 2020-2023

Fluorescence microscopy has long been a valuable tool for biological and medical imaging. Control of optical parameters such as the amplitude, phase, polarization and propagation angle of light gives fluorescence imaging great capabilities ranging from single molecule imaging to long-term observation of living organisms. While numerous fluorescence imaging techniques have been developed over the past decades, there is always an inevitable tradeoff among the spatial resolution, imaging speed, contrast, photodamage and the total cost when it comes to choose the appropriate microscope. A main goal of my dissertation research is to develop state-of-the-art microscope systems that exhibit unprecedented performance in …

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Explore And Design Novel Structures For More Efficient And Better Deep Convolutional Neural Networks, Min Wang Jan 2020

Explore And Design Novel Structures For More Efficient And Better Deep Convolutional Neural Networks, Min Wang

Electronic Theses and Dissertations, 2020-2023

Deep Convolutional Neural Networks have achieved remarkable performance on visual recognition problems, and have been extensively adopted in real-world applications, such as Apple's Face ID security system, autonomous driving cars, and automatic image tagging in online album services. One major concern in the development of CNNs is that their computational complexity grows along with the increase in their accuracy. Therefore, there is a continuous demand to find the right balance between accuracy and complexity in the design of CNN models. This dissertation focuses on designing various novel structures to enhance the performance of CNNs and their efficiency. Our efforts fall …

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Equivariance And Invariance For Robust Unsupervised And Semi-Supervised Learning, Liheng Zhang Jan 2020

Equivariance And Invariance For Robust Unsupervised And Semi-Supervised Learning, Liheng Zhang

Electronic Theses and Dissertations, 2020-2023

Although there is a great success of applying deep learning on a wide variety of tasks, it heavily relies on a large amount of labeled training data, which could be hard to obtain in many real scenarios. To address this problem, unsupervised and semi-supervised learning emerge to take advantage of the plenty of cheap unlabeled data to improve the model generalization. In this dissertation, we claim that equivariant and invariance are two critical criteria to approach robust unsupervised and semi-supervised learning. The idea is as follows: the features of a robust model ought to be sufficiently informative and equivariant to …

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Differential Recurrent Neural Networks For Human Activity Recognition, Naifan Zhuang Jan 2020

Differential Recurrent Neural Networks For Human Activity Recognition, Naifan Zhuang

Electronic Theses and Dissertations, 2020-2023

Human activity recognition has been an active research area in recent years. The difficulty of this problem lies in the complex dynamical motion patterns embedded through the sequential frames. The Long Short-Term Memory (LSTM) recurrent neural network is capable of processing complex sequential information since it utilizes special gating schemes for learning representations from long input sequences. It has the potential to model various time-series data, where the current hidden state has to be considered in the context of the past hidden states. Unfortunately, the conventional LSTMs do not consider the impact of spatio-temporal dynamics corresponding to the given salient …

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