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Introducing Additively Manufactured Electronic Design, Manufacturing, and Assembly at the University of Nevada, Reno
No full textThis thesis details the establishment and integration of additively manufactured electronics (AME) capabilities at the University of Nevada, Reno (UNR) with the Nano Dimension DragonFly IV and Essemtec Fox systems. Traditional printed circuit board (PCB) fabrication and surface mount technology (SMT) assembly processes are introduced and contrasted with the capabilities enabled by the Nano Dimension tools, including rapid in-house prototyping and 3D design freedom, which facilitate research and education at UNR. Prior to purchase, the DragonFly IV was evaluated through a 24 GHz antenna design and cost analysis. Operational and applications engineering experience was accumulated through a co-op with Nano Dimension, which included the development of AME fabrication and SMT assembly workflows. The installation and management of the tools in the Davidson Foundation Cleanroom is detailed, including the development of standard operating procedures (SOPs). Furthermore, the integration of AME into curriculum and research is explored by introducing the DragonFly IV into an undergraduate antennas course and by providing applications engineering and training to graduate researchers using the tools. Future work is discussed, which includes continued research in antennas, rectennas, and packaging applications, further curriculum integration, the development of a community userbase, and securing funding for the future maintenance and operation of the tools
Integrating the Risk Management of TSFs, WRFs, and HLFs
No full textThis paper was presented at the Heap Leach Solutions Conference, October 19-21, 2025, Sparks, Nevada.An essential aspect of effective mine waste management is the integration of best practices, risk management principles, and lessons learned from tailings storage facilities (TSFs) case histories. While TSFs governance has evolved significantly in recent years, with global mining companies aligning their practices with international standards such as the Global Industry Standard on Tailings Management (GISTM), similar efforts are needed for heap leach facilities (HLFs) and waste rock facilities (WRFs)-facilities that can pose comparable risks in certain contexts. Under these circumstances, the consequence classification for HLFs and WRFs remains a major challenge. Developed collaboratively by Capstone Copper and Nava Consulting, this paper presents a comprehensive approach to leaching ore and waste management, emphasising a standardised consequence classification system that integrates HLFs and WRFs alongside TSFs. Establishing a consistent classification framework is fundamental to improving risk management and operational safety for all types of ore mining and waste storage facilities. Furthermore, the paper proposes the development of a standard for the design, operation, and closure of HLFs and WRFs. By establishing a clear and structured standard, mining companies can ensure consistency across projects and operations, integrating risk management practices at every stage of a facility's life cycle. This approach is critical to minimize environmental and social impacts while enhancing safety, operational efficiency, and long-term sustainability in mine waste management. Also, this paper establishes the key pillars for the safe and responsible management of HLFs and WRFs, ensuring a comprehensive and structured approach to their governance. Finally, a consequence-based risk framework is proposed that evaluates the potential impacts of failure across all leaching ore and waste storage facilities. An integrated consequence classification system coupled with risk management processes ensure that mine waste risks are systematically incorporated into corporate risk management strategies. This allows for more effective prioritization of mitigation efforts and improved safety and environmental performance
Evaluating Online Sources – Lesson Plan
No full textStudents can articulate the importance of evaluating and vetting sources, online or otherwise. Additionally, students acquire techniques and strategies for evaluation
HARVESTING BLACKBODY RADIATION: A WIDEBAND RECTENNA APPROACH FOR LOW-POWER ENERGY HARVESTING
No full textThe purpose of this dissertation is to investigate the feasibility of harvesting electrical energy from blackbody radiation using rectennas. Blackbody radiation, commonly perceived as low-power thermal noise, is an energy source emitted by all objects in the universe. By aggregating this radiation over a wide frequency bandwidth, it may be possible to generate sufficient power to activate a rectifying Schottky diode, resulting in the conversion of heat radiation into usable DC electricity. To achieve this, we have looked into what it would take to design a wideband rectenna system. The rectenna system is capable of converting heat radiation into DC electricity by combining the use of an antenna and a high frequency rectifier. The antenna serves the purpose of converting the electromagnetic radiation, in this case heat noise, into an AC electric signal. This signal then goes into a Schottky diode rectifier and converts the AC signal into usable DC electricity. This wideband rectenna system would theoretically be able to harvest the heat energy across a broad frequency spectrum. Given the inherently low power density of blackbody radiation, special consideration is given to minimizing losses, improving bandwidth, and enhancing the gain of the system.
To validate the theoretical framework, multiple rectennas have been fabricated using the Dragonfly IV printer recently acquired by UNR. These rectennas were initially fabricated in segments, the rectifier component and the antenna component. Multiple measurements were performed to observe the rectification and performance of the various rectifiers printed. The performance, characteristics, and gain of the printed antennas were also measured and tested.
Ultimately, this dissertation demonstrates that while blackbody radiation presents unique challenges due to its low power density, strategic bandwidth aggregation and rectifier optimization can theoretically enable effective energy conversion. Experimental results provide insight into the potential for rectennas to serve as passive energy harvesting solutions, expanding the scope of wireless power generation in low-energy environments
Optimizing Gold Heap Leaching Performance: A Field Trial Using Ionquest 479
No full textThis paper was presented at the Heap Leach Solutions Conference, October 19-21, 2025, Sparks, Nevada.Gold heap leaching is a prevalent method for extracting gold from low-grade ore deposits, involving the percolation of a diluted cyanide solution through crushed ore. Despite its efficiency, the process faces challenges such as scaling and fouling due to the need to maintain oxidizing conditions for cyanidation and an alkaline pH, typically maintained by adding lime or caustic. These conditions can lead to the formation of mineral precipitates that cause scale buildup, reducing gold production, raising replacement costs and escalating water consumption. The effectiveness of scale inhibitors, such as Ionquest(R) 479, in mitigating these issues was evaluated during a field trial to improve operational efficiency and reduce maintenance costs. Ionquest(R) 479 was found to be highly effective in controlling complex scales in gold leaching systems, offering stability under high alkaline conditions and long residence times. The product combines scale inhibition and dispersing effects, effectively preventing scale formation in pipes, sprinkles, pumps, and recovery systems, thus improving gold adsorption onto activated carbon. Notably, Ionquest(R) 479 operates at low dose rates and provides significant reductions in downtime and maintenance costs. A field trial was conducted at a gold mine where the incumbent scale inhibitor was replaced with Ionquest(R) 479. Water analysis revealed a high potential for calcium sulfate (CaSO4) and moderate strontium sulfate (SrSO4) scale formation. Jar tests demonstrated that Ionquest(R) 479 could maintain 90% inhibition at a 10-ppm dose and completely inhibit scale formation at 30 ppm under conditions mimicking the field environment. The trial led to a reduction in monthly antiscalant consumption, while the main barren solution distribution pipe remained free from scale buildup, unlike with the previous scale inhibitor, which required regular cleaning and flushing. This resulted in a more consistent lixiviant flow to the heap leach pad and a significant reduction in the dripper replacement rate from 11 per week to just 4 per week, representing a 64% improvement. The use of Ionquest(R) 479 not only improved scale control but also contributed to a 34% reduction in scale inhibitor consumption, highlighting the product's cost-effectiveness and long-term operational benefits. The trial results confirm that Ionquest(R) 479 is a promising solution for addressing scaling issues in gold heap leaching processes. Future trials are recommended to explore the optimization of dose rates to further enhance the cost-benefit balance
MAPPING TERROR: EXPLORATORY SPATIAL DATA ANALYSIS AND THE LOCAL DYNAMICS OF TERRORISM IN NORTHERN IRELAND AND THE PHILIPPINES
No full textThis dissertation explores how terrorism clusters in space and time, and what those clusters can tell us about the local dynamics of political violence. While terrorism is often analyzed at national or global levels, this project shifts the focus to subnational geographies, using a mixed-method approach that combines exploratory spatial data analysis (ESDA) with structured qualitative comparison. This project uses georeferenced event datasets for two comparable cases: Northern Ireland and the Philippines. It applies spatial autocorrelation and density-based clustering to identify patterns in where and when violence occurs. These clusters serve as the unit of analysis for both within- and cross-case comparisons, allowing the study to link spatial patterns with changes in organizational activity, political context, and conflict dynamics. The structured, cluster-level approach enables a type of comparison that remains rooted in each case while also providing insights across them. This research provides a methodological framework for cluster-level analysis that bridges nomothetic and idiographic approaches. It shows how spatial data and case-sensitive comparison can be used together to explore how political violence is influenced by and reacts to its immediate context. In doing so, the project supports a broader shift toward mid-range theories in terrorism studies, emphasizing clarity, comparability, and context over abstraction or anecdote
Border-Lines, Volume I
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.Border-Lines is an interdisciplinary academic journal dedicated to the dissemination of research on Chicana/o-Latina/o cultural, political, and social issues. The journal seeks to publish scholarly articles drawn from a variety of disciplines such as Anthropology, Education, Geography, Public Health, Literary and Cultural Studies, Political Science, Social Work, and Sociology
Advanced Assessment of Inverter-based Resources-Storage Technologies on Modern Electric Grids in terms of Power Profiling, Ancillary Services, and Transient Stability
No full textThe integration of Inverter-Based Resources (IBRs) with energy storage presents significant challenges to modern power systems, including reduced dispatchability, limited reserve capacity, impaired ancillary service performance, and compromised transient stability. These complexities also hinder the applicability of conventional operational reliability indices. This dissertation addresses these challenges by developing advanced methodologies to enhance grid dispatchability, transient stability, ancillary service provision, and reliability assessment in systems with high penetration of IBRs and storage. Under hybrid power integration, diverse power profiles emerge, such as dispatchable, non-dispatchable, arbitrage, and multi-tier reserve generation, each with unique boundaries and operational roles. To manage these profiles effectively, a linear programming-based optimization framework is proposed to co-optimize unit commitment and reserve scheduling, accounting for the variability and uncertainty of renewable generation. The research further evaluates the co-integration of solar photovoltaic systems with energy storage in electricity markets, emphasizing dispatchability and reserve contributions to minimize operational costs and improve market responsiveness. In parallel, the study explores the impact of renewable integration on transient stability, particularly in low-inertia systems. By examining the transient and sub-transient responses of both conventional synchronous generators and renewable-based units, the dissertation introduces novel stability metrics better suited to capture the dynamic behaviors of evolving grid conditions. These metrics offer enhanced accuracy in reliability assessments and stability planning. Additionally, the work investigates harmonic mitigation and power quality improvements through filter-less multilevel Cascaded H-bridge (CHB) inverters utilizing high-frequency Gallium Nitride (GaN) switches. This approach demonstrates improved power conversion efficiency and reduced total harmonic distortion (THD). To support decentralized operation, a novel autonomous power-sharing method is developed using modified droop control, enabling effective active and reactive power management and ancillary service delivery in both grid-connected and islanded microgrid modes. Collectively, this research advances the integration of renewable energy by proposing robust control strategies, optimization frameworks, and hardware solutions that enhance the reliability, efficiency, and resilience of future power systems. The proposed contributions lay the foundation for more stable, sustainable, and economically viable energy infrastructures
AIEI Webinar Series on Balanced Mix Design (Session 5 of 5): Considerations for Quality Assurance
No full textThis webinar explores important considerations for incorporating Balanced Mix Design (BMD) tests into production and quality assurance processes. While many agencies begin by implementing BMD in mix design specifications, there is growing interest in extending its use to quality assurance. The session highlights key challenges and considerations that agencies should address when planning for BMD integration across the project lifecycle.United States Department of TransportationFederal Highway Administratio
Evaluation of the IDEAL-CT for Hveem-Designed Asphalt Mixtures in Nevada
No full textThis study focuses on evaluating the applicability and effectiveness of the Indirect Tensile Asphalt Cracking Test (IDEAL-CT) for Hveem designed asphalt mixtures in the State of Nevada. While IDEAL-CT has traditionally been applied to Superpave Gyratory Compacted (SGC) specimens; this study investigates its use with Hveem-compacted specimens, highlighting adaptations for smaller diameters. The sensitivity of the CT Index to changes in mix design parameters, such as aggregate gradation and asphalt binder content, was evaluated, and results were compared between Hveem and SGC compaction methods.Findings indicate that both specimen diameter and compaction method influence the IDEAL-CT test parameters, with differing effects on cracking performance. The study also explored the use of IDEAL-CT on Hveem-compacted specimens to determine the tensile strength for moisture damage evaluation in accordance with AASHTO T 283 (tensile strength ratio, TSR). In addition, the Moisture Induced Stress Tester (MiST) was examined as a potential alternative for the freeze-thaw cycle of moisture-conditioned specimens.
As an initial attempt to validate the CT Index for Nevada conditions, the LTPP SPS-10 project was used as a case study. Field core samples collected at different in-service periods within the first two years of pavement life, along with plant-produced asphalt mixtures, were tested for the CT Index. Field distress data for cracking were obtained from LTPP InfoPave and analyzed for potential correlations with the laboratory results. Limited cracking distress was observed during the early years following construction, which limited the comparison with core test results