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Experimental Evaluation of Merged-View Systems and VR-Based Reconstruction Approaches for Enhanced Mining Vehicle Teleoperation
No full textIn mining teleoperation, multi-view visualization systems can improve efficiency and safety but often impose a high cognitive load, causing operators to tunnel attention toward a single view. To explore a more efficient alternative, this study evaluated a merged-view interface that integrates multiple camera perspectives into a single coherent display. In a controlled experiment, 35 participants navigated a teleoperated rover robot along a 50 m simulated underground mine path under both multi-view and merged-view conditions. Task performance and eye-tracking data, including completion time, path adherence, and speed-limit violations, were recorded for comparison. Results showed that the merged-view system enabled 6 % faster completion times, 21 % higher path adherence, and 28 % fewer speed-limit violations. Eye-tracking metrics revealed more efficient and distributed attention in the merged view: blink rate decreased by 29 %, fixation duration shortened by 18 %, saccade amplitude increased by 11 %, and gaze-transition entropy rose by 14 %, reflecting broader and more adaptive scanning. The NASA Task Load Index (NASA-TLX), a widely used subjective workload assessment tool, indicated a 27 % reduction in perceived workload. Regression-based sensitivity analysis showed that gaze entropy was the strongest predictor of efficiency in the multi-view condition, whereas fixation duration dominated under merged-view visualization. For path adherence, blink rate was most influential in the multi-view setup (frequent disengagement reduced stability), whereas fixation duration was the primary predictor in the merged-view interface, reflecting steadier gaze and improved control. Overall, merged-view visualization enhanced situational awareness, reduced cognitive tunneling, and provided quantitative guidance for designing safer and more efficient teleoperation interfaces in hazardous mining environments. Complementing this empirical work, a review of VR-based teleoperation approaches highlights the potential of 3D reconstruction methods to create immersive environments with enhanced situational awareness. The review concluded that depth-based reconstruction is most effective for underground mining, while point-cloud modeling is more suitable for surface environments. Together, these findings demonstrate that merged-view visualization reduces cognitive tunneling, enhances safety and efficiency, and that VR approaches may provide the next frontier for advanced teleoperation interfaces in mining
Improving Lithium Extraction from Claystone: Maximizing Efficiency and Sustainability with Integrated Beneficiation and Sulfuric Acid Leaching
No full textThe fast paced electric vehicle (EV) adoption and the expansion of renewable energy storage systems has led to a resurgence in demand for Li, with domestic demand outpacing its production by more than 25% since 2019. Sedimentary claystones in Nevada are a new type of resource for lithium. The current industrial approach to extract lithium from these resources mostly employs direct sulfuric acid leaching and does not involve beneficiation to remove gangue minerals such as carbonates. This not only results in the excessive use of sulfuric acid but the generation of carbon dioxide as a byproduct of the leaching reaction. To improve the economics and sustainability of lithium extraction, it is desirable to incorporate a beneficiation step prior to the hydrometallurgical operation. In this study, a smectitic claystone was beneficiated using a previously developed method and subsequently leached using sulfuric acid. Response surface methodology (RSM) was employed to study the effects of acid concentration, leaching temperature and time, and solid-liquid ratio on the lithium extraction from the beneficiated claystone. The results showed that the beneficiation was able to recover 91% of lithium while rejecting 86% of calcium. The beneficiated claystone yielded a high lithium recovery of 89.18% after leaching at optimum conditions of 1.31 M acid concentration, leaching temperature of 80 °C, leaching time of 1.93 hours, and 26% solid-liquid ratio generated by response surface methodology (RSM). Compared with the industrial approach, the leaching process incorporating the beneficiation stage reduces the acid consumption from 106 g/g lithium to 23 g/g lithium and the environmental impact expressed in terms CO2 emissions from 4.26E-01 kg CO2eq/g lithium to 1.51E-01 kg CO2eq /g lithium
Search for Exotic Physics Modality in Multi-Messenger Astronomy with the Global Positioning System
No full textWe investigate a new way to search for exotic physics using multi-messenger astronomy. Here, exotic physics refers to theories beyond the now well-established Standard Model (SM) of elementary particles. Multi-messenger astronomy is the coordinated observation of different classes of signals from the same astrophysical source.When massive compact objects such as black holes or neutron stars merge, then along with gravitational waves (GWs), they may also release bursts of hypothetical scalar particles/fields which are ultralight, with masses , where is the speed of light. These hypothetical fields, referred to here as exotic low-mass fields (ELFs), would travel slightly slower than the GWs which propagate at the speed of light. The ELFs are hypothesized to transiently alter the fundamental constants of nature and thereby vary the atomic transition frequencies. If so, ELFs could be detected using atomic clocks on board the Global Positioning System (GPS) satellites. This work specifically focuses on the network of rubidium atomic clocks, which make up the majority of the GPS constellation. If ELFs interact with the known SM matter by temporarily altering fundamental constants, they would leave a distinct, “anti-chirp” timing signature across the GPS clock network. We search for ELF bursts temporally correlated with the GW trigger:~GW170817, detected by the LIGO–Virgo collaboration on August 17, 2017. Clock data from the GPS constellation are analyzed in a window bracketing this LIGO–Virgo GW trigger, and we construct correlated observables sensitive to propagating disturbances with near-luminal velocities. No statistically significant signatures are found. We translate this null result into improved constraints on the coupling strengths of candidate dark-sector fields to atomic clocks. These constraints surpass previous astrophysical bounds by several orders of magnitude, tightening the parameter space available for models of ultralight exotic scalar fields
Border-Lines, Volume XII
No full textBorder-Lines is an interdisciplinary and intersectional academic journal dedicated to the dissemination of research on Chicana/o-Latina/o cultural, political and social issues. Border-Lines is a refereed journal that seeks to publish scholarly articles drawn from a variety of disciplines such as anthropology, education, geography, human health, literary and cultural studies, political science, social work and sociology
The molecular mechanism of Dual leucine zipper kinase protein localization in neuronal stress signaling.
No full textNeurons, fundamental operational units of the nervous system, are intricately polarized cells comprised of three primary components: dendrites, a cell body, and an axon. Due to their distinct functions, precise protein localization within neurons is essential for maintaining neuronal homeostasis. Certain proteins exhibit notable enrichment in axon terminals, where they exert pivotal influences on neuronal function, morphology, and survival. Dual Leucine Zipper Kinase (DLK) modulates neuronal stress responses, including neuronal loss implicated in various neurodegenerative conditions. DLK is axonally expressed and is under constant suppression under normal conditions. Although DLK is known to localize in axons and has crucial roles, the mechanisms governing DLK localization in axons remain elusive. Therefore, understanding the molecular mechanisms of DLK localization is paramount for elucidating its functions and advancing therapeutic strategies for numerous neurodegenerative diseases. Chapter 1 describes known mechanisms involved in protein localization in neurons, such as transport, local synthesis, diffusion, and degradation. Rab GTPases are crucial in regulating the interaction between cargoes and localization machinery. Moreover, this chapter demonstrates that disruptions in these mechanisms impair proper protein localization, leading to various neurodegenerative diseases.
In Chapter 2, we find that Wallenda (Wnd), the Drosophila ortholog of DLK, is highly enriched in the axon terminals, and such localization is essential for Highwire-mediated suppression of Wnd protein levels. Moreover, Rab11 plays a critical role in regulating Wnd protein turnover to inhibit excessive neuronal loss.
Finally, Chapter 3 discusses and addresses future directions, focusing on the study of palmitoylation-defective Wnd mutants, wild-type Wnd axon transport, and protein turnover machinery.
This thesis provides a novel demonstration of the functional role of axonal protein localization in protein turnover to maintain stable stress signaling. Furthermore, it defines the fundamental molecular mechanisms of the initial motif and axonal sorting pathway from the cell body to the axon terminals, leading to more predictive models of protein localization. As a result, demonstrating the role of axonal protein localization will offer new insights into its function in neurons
The Audacity of Happiness: The Good Life for People in Recovery from Opiate Addiction
No full textThis dissertation focuses on what the good life means to help-seekers and workers at an NGO in Northern Nevada that has served the community for more than two decades, which I will name Life. At Life, nurses, counselors, psychologists, medical doctors and former substance users work together towards the help-seekers’ recovery from opiate addiction. This is the ideal place to explore how people who struggle due to a chaotic relationship with opiates receive care in the form of therapy, medication, resource identification, healthcare information, parenting, nutrition, cooking, reproductive health classes, yoga and arts trainings, and how simultaneously they give each other support by sharing past and present experiences pertaining to all the walks of life they find relevant. Moreover, staff and help-seekers often give one another support outside the structured settings of therapy, medication dispensation and group therapy, connecting while sharing ways to face up to present challenges, many pertaining to pregnancy, birth, mothering, childcare, addiction, and discussing the relationship between past and present challenges as well as hopes. The staff also assess each help-seeker’s individual and changing needs by organizing and attending family events designed to support women. In these settings women help-seekers, their children, their siblings, parents, spouses, romantic partners can come together and talk about their lives, experiences with addiction, childcare, and ways to think about the future
Impacts of pesticides: From neurons and microbes to pollination services
No full textThe decline of pollinators and other insects has been linked to exposure to pesticides, which have become ubiquitous across landscapes. Although these chemicals can cause mortality, they also cause a wide variety of sublethal impacts to pollinator health, which nevertheless can have indirect impacts on survival. In my first chapter, I use an electrophysiological approach to understand disruptions to olfactory processing in the well-conserved and well-studied Drosophila melanogaster olfactory system. I show that exposure to an insecticide caused a reduction in activity at the single-neuron level and delayed the return to baseline activity of the whole antenna. In addition, flies exposed to insecticide had a greater relative preference for ethanol-laced pineapple juice than control flies, demonstrating that neuronal disruptions may scale up to shift food preferences. In my second chapter, I examine intraspecific differences in the sensitivity of a wild bumble bee (Bombus vosnesenskii) to multiple pesticides, including changes to the microbiome. Overall, site-level factors played a strong role in determining bee response to pesticide exposure, but gut microbiome community composition and total bacterial abundance did not exhibit the same site by treatment interaction nor exhibit any sensitivity to pesticides. Although the gut microbiome of these bees was not impacted by these pesticides at the concentrations tested, this work demonstrates the importance of site-level factors driving intraspecific differences in wild bee survival when exposed to multiple different pesticides. Finally in my third chapter, I ask how the treatment of a wildflower (Penstemon strictus) with a fungicide, an insecticide, and the combination with both chemicals alter pollination services. I show that visitation was best predicted by flower number, and plants that received the fungicide treatment or treatment of both chemicals had the most flowers and therefore, the highest visitation. However, although these plants had the highest visitation, plants treated with any pesticide had fewer and lighter seeds. These results show pollinators may not be deterred by the presence of harmful chemicals in plant tissue, but despite this, these wildflowers experience a fitness reduction when these chemicals are present
Multi-scale Modeling in Novel Materials Design
No full textAdvancements in the manufacturing industry drive the creation of innovative technological products, with materials design at its core. Understanding the physical processes dictating mechanical properties is crucial for accurate material design. Traditionally, this involved costly experimentation to test materials under various conditions such as static loading, fatigue loading, or thermal irradiation. On the other hand, modern multiscale modeling techniques offer a more efficient approach, reducing trial and error and enabling the design of material models that accurately describe complex behaviors. At the nanoscale, molecular dynamics (MD) simulations track atomistic microstructural evolution, often impossible to observe experimentally. Meanwhile, phase-field simulations at the meso-continuum scales mathematically model material behavior with a broader range of applications. For instance, MD simulations have elucidated monotonic loading and quenching mechanisms in magnesium (Mg) and titanium (Ti), delving into twinning nucleation and growth processes. While classical twinning theory typically relies on a dislocation-based approach, our recent simulation results indicate twinning can also arise from phase transformations. Depending on the material's phase diagram, specific types of twins, such as {101 ̅2} and {101 ̅1} twins, can form. Moreover, we explore defects in the lesser discussed ωphase, including twinning within this phase. At the meso-continuum scale, we discuss a framework for multiscale coupled phase field modeling of fracture and amorphization in boron carbide material systems. This framework investigates the unusual impact softening observed experimentally in this material, with practical implications for improving its application in bulletproof vests. We then extend the fracture part of this model to represent the cyclic fatigue process in Single Edge Notched Tension (SENT) and Compact Tension (CT) specimens, which are commonly used to investigate the fracture toughness of various materials
Variability in Pyroconvection During the Bootleg Fire in 2021
No full textWe examine the factors controlling the depth and vigor of pyrocumulus (pyroCu) and pyrocumulonimbus (pyroCB) clouds during the Bootleg Fire in Oregon, USA (July 2021). A combination of Next Generation Weather Radar (NEXRAD) and Geostationary Operational Environmental Satellite number 17 (GOES-17) observations are used to characterize the wildfire’s plume depth and the presence of pyroCu/Cb. These data are contextualized with High Resolution Rapid Refresh (HRRR) analysis fields to examine the thermodynamic structure of the atmosphere, and with GOES-17 Fire-Radiative Power (FRP) to characterize the fire’s forcing for plume development. Results show a range of plume depths and pyroconvective outcomes, spanning dry convective columns with maximum depths <8 km, to deep pyroCb (~13 km MSL) with precipitation and lightning. We find that the plume height relative to the convective condensation level (CCL) discriminates between pyroCu and non-pyroCu periods. For pyroCb formation, we examine FRP relative to the PyroCb Firepower Threshold (PFT), which measures how much energy is needed to initiate moist convection. We find that the FRP’s exceedance of the PFT adequately predicts pyroCb initiation, albeit not necessarily its longevity or spatial extent. We also explore the relationship between the plume rise geometry and pyroCb formation, finding that plume uprightness is associated with its ability to cross the CCL and form pyroCu/Cb. Lastly, we explore the terms Fire Convective Available Potential Energy (Fire CAPE) and Fire Convective Inhibition (Fire CIN) to describe the instability of the environment around the fire, providing insights into the fire’s proclivity to initiate pyroCu/Cb. Ultimately our results will help forecasters identify when a fire is likely to produce pyroCb
Resource-Efficient Edge Computing and Lightweight Traffic Fingerprinting for Scientific Applications
No full textThe explosive growth of the Internet of Things (IoT) and the increasing demand for real-time, data-intensive applications present significant challenges in network management, device identification, and resource efficiency. This thesis addresses these challenges through two approaches: resource-efficient edge computing for scientific applications and lightweight network traffic fingerprinting for IoT environments.In fire detection systems like AlertWildfire, integrating edge devices significantly reduces latency by up to 70% and bandwidth consumption by 51% by enabling local data processing. For IoT device identification, this research introduces FlexiNet, a lightweight fingerprinting system using genetic algorithms, achieving 96% accuracy while reducing processing time and memory usage by 7% and 56%, respectively. An alternative Locality-Sensitive Hashing (LSH) method further improves accuracy by 12%, demonstrating its scalability in constrained environments.
These advancements highlight the synergy between edge computing and efficient traffic fingerprinting in addressing the unique demands of scientific and industrial IoT systems. By optimizing both latency-critical operations and resource-intensive identification processes, this research bridges the gap between computational efficiency and scalability while providing a flexible framework adaptable to broader IoT applications. The findings lay a foundation for enhancing network management, improving security, and fostering the development of adaptive systems in constrained and dynamic environments