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Hydrothermal Alteration Mapping Of The Northern Coongan Greenstone Belt Using Remote Sensing Imagery, Meaza Bogale, Elias Woldeyohanis Sep 2026

Hydrothermal Alteration Mapping Of The Northern Coongan Greenstone Belt Using Remote Sensing Imagery, Meaza Bogale, Elias Woldeyohanis

Journal of Sustainable Mining

Archean greenstone belts are well known for their ore deposits, diverse lithostratigraphy, and well-preserved evidence from the early Earth. The Northern Coongan Greenstone Belt is an Archean greenstone belt that is part of the Eastern Pilbara Craton of Western Australia. The rock units of this area have the potential to be sources of valuable mineral deposits, which could be economically beneficial for extraction. Studies have been conducted in the northern Coongan greenstone belt, mostly using geological field methods and geophysical interpretations, excluding remote sensing methods for mapping mineral indices. Therefore, this study aims at providing surface mineral distribution maps and …


Sedimentary Dynamics In Tubular Sandstone Caves, Porto União, Southern Brazil, Leandro Bianchini, Julio Cesar Paisani Sep 2026

Sedimentary Dynamics In Tubular Sandstone Caves, Porto União, Southern Brazil, Leandro Bianchini, Julio Cesar Paisani

International Journal of Speleology

Clastic sedimentation in sandstone caves remains poorly understood, particularly in systems with tubular morphology. This study investigates sedimentation, reworking, and sediment removal dynamics in the Legru Cave system, southern Brazil, based on the integrated analysis of sedimentary facies, microstructures, and microfeatures, combined with optically stimulated luminescence dating. The results indicate that conduit infilling is dominated by high-density flows, including cohesive debris flows, partially diluted multiphase flows, and flows with intermediate rheological behavior between mud flow and hyperconcentrated flow, in addition to shallow flow alternations. Sediment supply is predominantly allochthonous, related to hillslope-derived material delivered by overland flow and mud flows, …


Cyberspace Collaborative Awareness: A Model For Unity Of Effort In Homeland Defense, Mike Knapp, Sean Atkins, Matthew Mclaughlin Sep 2026

Cyberspace Collaborative Awareness: A Model For Unity Of Effort In Homeland Defense, Mike Knapp, Sean Atkins, Matthew Mclaughlin

Joint Force Quarterly

The increasing frequency and severity of cyberattacks against U.S. critical infrastructure continue to confound homeland defense efforts. Defending against state cyber campaigns that threaten the nation’s most critical systems requires a new awareness model that can enable unity of effort across public and private actors. Examining homeland defense awareness in other domains reveals principles and approaches that can inform the development of a collaborative awareness model in cyberspace. This new framework acknowledges the interconnectedness of government and commercial networks and the independent goals of each player in the domain. Doing so provides a viable path to achieving shared domain awareness …


From Data To Victory: The Race For Analytic Superiority In Warfare, Robert Grossman, Emily Goldman Sep 2026

From Data To Victory: The Race For Analytic Superiority In Warfare, Robert Grossman, Emily Goldman

Joint Force Quarterly

Artificial intelligence technologies have reached a tipping point after decades of development. They are diffusing widely across defense and national security applications. Twenty-first century warfighters rely on analytic models in all systems, at all echelons, and in all domains. As more powerful models built on ever larger data sets become ubiquitous, militaries are in a new competition to deploy artificial intelligence. Operational art must embrace “analytic superiority.” This is the operational advantage from collecting and ingesting data, building robust models and computing infrastructure, deploying the models into operational systems, and denying adversaries' ability to do the same

This article explains …


How Euler Could Have Done It: Euler And An Integral Of Ramanujan, Alexander Aycock Sep 2026

How Euler Could Have Done It: Euler And An Integral Of Ramanujan, Alexander Aycock

Euleriana

We present a derivation of a definite integral discovered by Ramanujan (1887–1920) in his 1915 paper "Some Definite Integrals," from formulas and ideas already developed by Euler (1707–1783). Additionally, it is argued why Euler did not discover Ramanujan's integral himself, although he had all tools required for this task at his disposal.


A Note On Euler's Definition Of The Sum Of A Divergent Series, Alexander Aycock Sep 2026

A Note On Euler's Definition Of The Sum Of A Divergent Series, Alexander Aycock

Euleriana

We outline Euler's theory of divergent series and present another approach he could have taken to sum his ``factorial series". Finally, we address the contradictions that arise from his concept of a sum of a divergent series.


Euler's Explorations Of Extremal Ellipses, Jonathan David Evans Sep 2026

Euler's Explorations Of Extremal Ellipses, Jonathan David Evans

Euleriana

In the 1770s, Euler wrote a series of papers (E563, E691 and E692) about finding the ellipse with minimal area or perimeter in the family of all ellipses passing through a fixed set of points. This is a translation of all three papers from the original Latin, together with a commentary which discusses Euler's results and an appendix which addresses a question from E691 which Euler left for others to consider.


Arithmetic Theorems, Demonstrated By A New Method: An English Translation Of E271, Brendon Lasell Sep 2026

Arithmetic Theorems, Demonstrated By A New Method: An English Translation Of E271, Brendon Lasell

Euleriana

After defending in general terms the value of arithmetic demonstrations, where, according to Euler, the force of genius shines more brightly than in any other kind of demonstration, he goes on to let the force of his own genius shine forth in demonstrating the fact that, for any pair of relatively prime numbers a and N, aϕ(N) − 1 is always divisible by N, where we anachronistically denote by ϕ(N) the number of numbers less than N that are relatively prime to it. He approaches this theorem by considering the remainders that result when the numbers in an arithmetic …


On Double Integral Formulas: An English Translation Of E391, Thomas W. Polaski Sep 2026

On Double Integral Formulas: An English Translation Of E391, Thomas W. Polaski

Euleriana

In this paper, Euler investigates the theory of double intergrals to uses them to find areas, volumes and surface areas. He considers transformations of variables in double integrals. After showing that simple multiplication of the transformed differentials is not appropriate, he derives the formula for a change of variables in double integrals. Euler then uses such changes of variables to investigate areas and volumes, and then turns his attention to the so-called ``Florentine problem.'' This problem requires one to remove four equal windows from a hemispherical surface so that the remaining area is equal to the area of a square. …


Eulerian Problem Solving, Christopher Goff, Erik Tou Sep 2026

Eulerian Problem Solving, Christopher Goff, Erik Tou

Euleriana

An introduction to the contents in Volume 6 (Issue 2) of Euleriana.


Bitseat: Reimagining The Financing For Airliners Using Nonfungible Tokens (Blockchain Technology), Edwin S. Ongola Sep 2026

Bitseat: Reimagining The Financing For Airliners Using Nonfungible Tokens (Blockchain Technology), Edwin S. Ongola

Journal of Aviation Technology and Engineering

This essay describes how blockchain technology, particularly nonfungible tokens, can be used to raise funding for airliners. The essay begins with a brief overview on the costs, categories, and acquisition methods of airliners. After that, the essay introduces concepts on blockchain technology, tokens, and smart contracts. The essay then touches on how nonfungible tokens can be used to facilitate fractional ownership of airliners. From there, the essay discusses Bitseat, a conceptual nonfungible token for fractional ownership of airliners, covering its overall design, appeal, marketplace alternatives, and challenges. Finally, in the discussion, the essay summarizes the overall concept and outlines its …


Re: Approval Letter For The Butte Priority Soils Operable Unit (Bpsou) Draft Final Unreclaimed Sites: Ur-42 Site Evaluation Summary Report (Sesr) (Dated July 22, 2026), Molly Roby Sep 2026

Re: Approval Letter For The Butte Priority Soils Operable Unit (Bpsou) Draft Final Unreclaimed Sites: Ur-42 Site Evaluation Summary Report (Sesr) (Dated July 22, 2026), Molly Roby

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.


Approval Letter For The Butte Priority Soils Operable Unit (Bpsou) 2026 Final Backfill And Cover Soil Quality Assurance Project Plan (Qapp) Dated August 26, 2026, Molly Roby Sep 2026

Approval Letter For The Butte Priority Soils Operable Unit (Bpsou) 2026 Final Backfill And Cover Soil Quality Assurance Project Plan (Qapp) Dated August 26, 2026, Molly Roby

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.


Re: Approval Letter For The Butte Priority Soils Operable Unit, Draft Final Unreclaimed Sites: Ur-31 Site Evaluation Summary Report, Molly Roby Sep 2026

Re: Approval Letter For The Butte Priority Soils Operable Unit, Draft Final Unreclaimed Sites: Ur-31 Site Evaluation Summary Report, Molly Roby

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.


Toxicity Ahead: Forecasting Conversational Derailment On Github, Mia Mohammad Imran, Robert Zita, Rahat Rizvi Rahman, Preetha Chatterjee, Kostadin Damevski Sep 2026

Toxicity Ahead: Forecasting Conversational Derailment On Github, Mia Mohammad Imran, Robert Zita, Rahat Rizvi Rahman, Preetha Chatterjee, Kostadin Damevski

Computer Science Faculty Research & Creative Works

Toxic interactions in Open Source Software (OSS) communities reduce contributor engagement and threaten project sustainability. Preventing such toxicity before it emerges requires a clear understanding of how harmful conversations unfold. However, most proactive moderation strategies are manual, requiring significant time and effort from community maintainers. To support more scalable approaches, we curate a dataset of 159 derailed toxic threads and 207 non-toxic threads from GitHub discussions. Our analysis reveals that toxicity can be forecast by tension triggers, sentiment shifts, and specific conversational patterns.We present a novel Large Language Model (LLM)-based framework for predicting conversational derailment on GitHub using a two-step …


Δ−Scuti Star Hr 1170, Salman A. Nejad Sep 2026

Δ−Scuti Star Hr 1170, Salman A. Nejad

Aquila: The Journal of Embry-Riddle Observatory

HR 1170, a variable star in the constellation Perseus, exhibits multi-periodic pulsations consistent with its classification as a δ−Scuti star. Through photometric and spectroscopic observations using the 1-meter ERAU telescope and the SARA-RM telescope, this study investigates its variability and spectral characteristics. Photometry conducted over several nights reveals pulsation periods that closely align with previously reported values. Time-resolved spectroscopy highlights prominent absorption features, including Balmer lines and metallic elements, offering further insights into the star’s atmospheric dynamics.


Taut And Dupin Submanifolds (Updated Version), Thomas E. Cecil Sep 2026

Taut And Dupin Submanifolds (Updated Version), Thomas E. Cecil

Mathematics and Computer Science Department Faculty Scholarship

This is an updated version of the paper [29] by the author which originally appeared in 1997. The original paper was a survey of the closely related fields of taut and Dupin submanifolds of Euclidean space, and this updated version includes many results in the field that have appeared since the publication of the original version. The emphasis is on stating results in their proper context and noting areas for future research, and relatively few proofs are given. The important class of isoparametric hypersurfaces is surveyed in detail, as is the relationship between the two concepts of taut and Dupin. …


Draft Final 2023 Unreclaimed Sites Sampling: Ur-43 Site Evaluation Summary Report, Pioneer Technical Services, Inc. Sep 2026

Draft Final 2023 Unreclaimed Sites Sampling: Ur-43 Site Evaluation Summary Report, Pioneer Technical Services, Inc.

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.


On-Shell Compression And Reconstruction (Oscar) Of Monochromatic Wave Fields In Weakly Scattering Media, Pablo Jara, Alexey Yamilov Sep 2026

On-Shell Compression And Reconstruction (Oscar) Of Monochromatic Wave Fields In Weakly Scattering Media, Pablo Jara, Alexey Yamilov

Research Data

Overview

This deposit contains one realization of each of the two simulation platforms of Ref. [1], a two-dimensional (2D) scalar field and a three-dimensional (3D) vector-field component, together with two self-contained Python scripts that perform On-Shell Compression and Reconstruction (OSCAR) on them. Each script Fourier-transforms the stored field, measures the shell radius from the spectrum, retains only the Fourier components inside the shell of full width α/ℓs around it for α = 1, 3, 5, 8, 12, reconstructs the field by the inverse transform, and plots the reconstructed intensities, panels (a)–(e), next to the original field, panel (f), on a …


Representing Post-Fire Reality: An Empirically Informed Temperature Index Approach To Post-Fire Hydrologic Modeling In Oregon's Western Cascades, Logan Hastings Sep 2026

Representing Post-Fire Reality: An Empirically Informed Temperature Index Approach To Post-Fire Hydrologic Modeling In Oregon's Western Cascades, Logan Hastings

Dissertations and Theses

The invaluable water resources stored in snowpack face mounting threats from rising temperatures, drought, shifts in precipitation regimes, and increased fire frequency, which pose challenges to operational hydrologic modeling in Oregon's sensitive maritime snowpacks. The gridded temperature index (GTI) approach in operational models like the Hydrological Engineering Center's Hydrologic Modeling System (HEC-HMS) from the U.S. Army Corps of Engineers remains in common use for its minimal data requirements, but how GTI parameterizations should adapt to post-fire conditions is largely unknown.

This research assessed the impact of the 2020 Lionshead Fire on HEC-HMS performance in the North Santiam River basin across …


Developing A Deep Learning-Based Artificial Intelligence System For Detecting Scientific Misinformation On Digital Platforms, Shorouq Al-Awawdeh, Ayah Al- Jafari Sep 2026

Developing A Deep Learning-Based Artificial Intelligence System For Detecting Scientific Misinformation On Digital Platforms, Shorouq Al-Awawdeh, Ayah Al- Jafari

Middle East Journal of Communication Studies

Objectives: This study develops and evaluates an Arabic scientific misinformation detection system by fine-tuning AraBERT-base-v2. It examines the effects of early stopping and input sequence length on model performance, interprets selected linguistic characteristics associated with misleading content, and discusses the limitations of using machine-translated data.

Methodology: The study adopted a mixed-methods design, employing a systematic integration of quantitative and qualitative approaches, supported by an interpretive qualitative reading. The initial database consisted of 23,546 records, including 123 Arabic articles collected from the Akeed, Sheek, and Taqeen platforms, and 23,423 foreign-language records drawn from the GossipCop and PolitiFact collections within FakeNewsNet. After …


The Evolution Characteristics Of Gas Pressure Around Coal Seam Directional Long Extraction Boreholes With Nonlinear Extraction Negative Pressure, Zhang Qi, Jia Jinlong, Li Zhiguo, Zhang Longgang, Qin Zhengyuan, Zhang Weizhong, Li Jin Sep 2026

The Evolution Characteristics Of Gas Pressure Around Coal Seam Directional Long Extraction Boreholes With Nonlinear Extraction Negative Pressure, Zhang Qi, Jia Jinlong, Li Zhiguo, Zhang Longgang, Qin Zhengyuan, Zhang Weizhong, Li Jin

Journal of Sustainable Mining

Nonlinear pressure of coal seam gas in the directional borehole and surrounding areas affects extraction efficiency. A multi-field coupling numerical model, including gas desorption, diffusion, fracture seepage, and borehole extraction, is developed for the No. 3 coal seam of the GJH mine. Using the numerical simulation method of control variables, extraction was developed to investigate the nonlinear evolution of axial pressure gradients in directional long borehole and the spatiotemporal response characteristics of gas pressure. Results show that coal seam seepage pressure exhibits a nonlinear radial gradient attenuation around the borehole, evolving through rapid pressure change, stabilization, and slow adjustment. The …


From Data To Decision-Making: The Role Of Local Digital Twins In Cross-Domain Management Within Municipalities – A Research-In-Progress Study In Veenendaal, Diana M.E. Boekman, Koen Smit, Guido Ongena, Rob Peters Sep 2026

From Data To Decision-Making: The Role Of Local Digital Twins In Cross-Domain Management Within Municipalities – A Research-In-Progress Study In Veenendaal, Diana M.E. Boekman, Koen Smit, Guido Ongena, Rob Peters

Communications of the IIMA

Municipalities are facing increasingly complex, interconnected challenges in areas like housing, climate adaptation, mobility, and social policy. Local Digital Twins (LDTs) are seen as a promising tool to make this complexity more understandable and support decision-making. At the same time, both literature and practice show that few initiatives get past the pilot phase, even though getting through that phase is essential for successful long-term adoption.

This paper presents a research-in-progress study on the development and application of an implementation method for LDT technology within the municipality of Veenendaal, based on human values rather than driven by technological possibilities. Based on …


A Novel Entropy Based Maintainability Measurement Algorithm For Java Source Code., Remi M. Yusuf Mr, Md Shadab Mashuk, Julian Bass Sep 2026

A Novel Entropy Based Maintainability Measurement Algorithm For Java Source Code., Remi M. Yusuf Mr, Md Shadab Mashuk, Julian Bass

Communications of the IIMA

Software metrics play a central role in assessing and managing the quality of software systems providing quantitative insights into attributes such as complexity, reliability, rigidity, modifiability and maintainability. Among these, maintainability is particularly critical, as it directly influences the ease of system evolution, long-term sustainability, and overall cost effectiveness. Despite the widespread use of metric-based maintainability measurement algorithms, capturing a value that reflects the maintainability situation of software source code remains a challenging task, especially in the presence of design deficiencies such as code smells. To measure changes in maintainability, this study experimentaly characterises the relationship between code smells and …


Broadening The Community Of Nudibranch Enthusiasts Through Multilingual Educational Programming To Increase Climate Advocacy Engagement, Richelle Li Tanner, Cintya Felix Mendivil, Ashley Lam, Lorena Muñoz, Micah Kim, Elena G. Morales Poot, Gabrielle Keeler-May Sep 2026

Broadening The Community Of Nudibranch Enthusiasts Through Multilingual Educational Programming To Increase Climate Advocacy Engagement, Richelle Li Tanner, Cintya Felix Mendivil, Ashley Lam, Lorena Muñoz, Micah Kim, Elena G. Morales Poot, Gabrielle Keeler-May

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Environmental literacy and advocacy for environmental protections are essential components of responsible stewardship. For coastal communities, stewardship requires knowledge of ocean processes and the biological communities living within these ecosystems. While many studies highlight difficulties in engaging American audiences in environmental concern and stewardship due to hyper-individualistic societal values, tidepooling is one recreational pathway to coastal community engagement that strengthens sense of place, and therefore, responsibility to protect natural resources. We sought to broaden the tidepooling community to include more diverse voices through a participatory science program with inland city-dwelling, multilingual, and non-English speaking adults. Using nudibranchs as an environmental …


Final Butte Priority Soils Operable Unit Unreclaimed Sites Field Sampling And Investigation Plan: Ur-52 Area West Of Bres No. 133 – Dexter Mill, Mike Mcanulty Sep 2026

Final Butte Priority Soils Operable Unit Unreclaimed Sites Field Sampling And Investigation Plan: Ur-52 Area West Of Bres No. 133 – Dexter Mill, Mike Mcanulty

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.


Final Butte Priority Soils Operable Unit Unreclaimed Sites Field Sampling And Investigation Plan: Ur-52 Area West Of Bres No. 133 – Dexter Mill, Mike Mcanulty Sep 2026

Final Butte Priority Soils Operable Unit Unreclaimed Sites Field Sampling And Investigation Plan: Ur-52 Area West Of Bres No. 133 – Dexter Mill, Mike Mcanulty

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.


Monthly Progress Report Butte Priority Soils Operable Unit Consent Decree Partial Remedial Design/Remedial Action And Operation And Maintenance, Josh Bryson Sep 2026

Monthly Progress Report Butte Priority Soils Operable Unit Consent Decree Partial Remedial Design/Remedial Action And Operation And Maintenance, Josh Bryson

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.


Butte Priority Soils Operable Unit Final Butte Priority Soils Operable Unit Unreclaimed Sites Field Sampling And Investigation Plan: Ur-41 – Montana Street And Interstate 90, Mike Mcanulty Sep 2026

Butte Priority Soils Operable Unit Final Butte Priority Soils Operable Unit Unreclaimed Sites Field Sampling And Investigation Plan: Ur-41 – Montana Street And Interstate 90, Mike Mcanulty

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.


Final Butte Priority Soils Operable Unit Unreclaimed Sites Field Sampling And Investigation Plan: Ur-51 –Area Near Bres No. 50 – Zelia And Mountain Con Mine, Mike Mcanulty Sep 2026

Final Butte Priority Soils Operable Unit Unreclaimed Sites Field Sampling And Investigation Plan: Ur-51 –Area Near Bres No. 50 – Zelia And Mountain Con Mine, Mike Mcanulty

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.