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Articles 7831 - 7860 of 291657

Full-Text Articles in Physical Sciences and Mathematics

Photoflow Synthesis And Characterization Of Cis- And Trans-N-Isohumulone, Gregory M. Giovine, Bradley Gallow, Trevor Smith, Bruce Hamper Dec 2025

Photoflow Synthesis And Characterization Of Cis- And Trans-N-Isohumulone, Gregory M. Giovine, Bradley Gallow, Trevor Smith, Bruce Hamper

Undergraduate Research Symposium

Previously published efforts by the Hamper group demonstrated the viability of photochemistry in the isomerization of n-humulone to n-isohumulone. Photochemical isomerization reactions of n-humulone performed under 400nm light over 8 hours resulted in high yields (84% reported) of largely trans-n-isohumulone (>95%). These promising results invited further examination of the photochemical process and the application of photoflow procedure. Herein we report the beginnings of a comprehensive slate of n-humulone isomerization reactions performed under iterative photoflow conditions.


Nature Naturing In And As Place, Edward S. Casey Dec 2025

Nature Naturing In And As Place, Edward S. Casey

Duquesne Studies in Phenomenology

In this brief article, I single out two distinctly different kinds of natural place, attempting to show how these not merely contrast with each other but display larger patterns or tendencies that are also found in many other sorts of place. This is to take one integral step to a larger ecology of places provided by the natural world and from which human and nonhuman beings draw life and motion that sustain and support many ways of existing on earth. Without such places, we—and every other form of life—would perish or would not even exist to begin with. It is …


Connecting Business Innovation & Climate Impact, San Diego Regional Climate Collaborative, Alexander Pourfard, Aranza Ruvalcaba, Fowzia Farah Dec 2025

Connecting Business Innovation & Climate Impact, San Diego Regional Climate Collaborative, Alexander Pourfard, Aranza Ruvalcaba, Fowzia Farah

San Diego Regional Climate Collaborative

The La Mesa Green Business Network (GBN) is a City-led initiative developed in partnership with the San Diego Regional Green Business Network to advance local climate goals by engaging the business community in practical, measurable sustainability actions. Launched in 2022 as part of La Mesa’s Climate Action Plan, the GBN addresses common barriers faced by small and medium-sized businesses such as limited capacity, resources, and technical expertise by providing free, industry-specific consulting, certification, and public recognition. Through tailored guidance on energy efficiency, water conservation, waste reduction, and transportation practices, the program translates citywide climate objectives into on-the-ground action while delivering …


Design, Synthesis And Biological Activities Of N-Substituted Phthalimide Derivative, Beaula Mangundah Dec 2025

Design, Synthesis And Biological Activities Of N-Substituted Phthalimide Derivative, Beaula Mangundah

Honors Theses

Phthalimides are a group of compounds among bicyclic non-aromatic nitrogen heterocycles that have gained recognition for their bioactivity across various fields, notably anti-cancer, anti-microbial, anti-oxidant, and anti-inflammatory. This study discusses the synthesis of a novel phthalimide derivative and provides an analysis of its biological activity. It was conducted through a Boric acid Imide synthesis and yielded a successful derivative using hexylamine. The product was evaluated in vitro for antimicrobial, anticoagulant, and anti-inflammatory properties using Kirby-Bauer disk diffusion, clotting time, hemolysis inhibition, and protein denaturation assays. It showed mild anticoagulant and anti-inflammatory activity.


Advanced Soliton Structures And Elliptic Wave Patterns In A Sixth-Order Nonlinear Schrödinger Equation Using Improved Modified Extended Tanh Function Method, Mina Fahim, Hamdy Mohamed Ahmed, Islam Samir, Kamal Dib Dec 2025

Advanced Soliton Structures And Elliptic Wave Patterns In A Sixth-Order Nonlinear Schrödinger Equation Using Improved Modified Extended Tanh Function Method, Mina Fahim, Hamdy Mohamed Ahmed, Islam Samir, Kamal Dib

Basic Science Engineering

In this work, a sixth–order extension of the nonlinear Schrödinger equation (NLSE) within its integrable hierarchy is investigated to model higher–order nonlinear and dispersive effects relevant to optical fiber systems and nonlinear wave propagation. By employing the Improved Modified Extended Tanh Function Method, a comprehensive family of exact analytical solutions is derived, encompassing bright and dark solitons, singular soliton structures, and singular periodic solutions. In addition, solution families expressed in terms of Jacobi elliptic functions, Weierstrass doubly periodic elliptic functions, and exponential profiles are obtained. The novelty of this study lies in extending the analytical framework of the NLSE hierarchy …


Gauss’S Method For Orbital Determination, Milagros Tamara Giraldo Dec 2025

Gauss’S Method For Orbital Determination, Milagros Tamara Giraldo

Honors Program Theses and Projects

Accurately predicting the orbital trajectory of celestial objects is essential for precise spacecraft navigation, planning planetary missions, avoiding potential collisions with space debris, and studying the long-term stability of planetary systems. Gauss’s method for orbital determination provides a way to predict the path of a celestial body accurately using only a small number of observations. In this project, we create an implementation that is not just a tool for executing Gauss’s method, but also an opportunity to study the formulation of the method itself. It allows for a practical and detailed examination of how different inputs, assumptions, and numerical choices …


Enhancing Silicon Sampling In Large Language Models: Fine-Tuning Techniques Using Survey Data, Davis P. Forster Dec 2025

Enhancing Silicon Sampling In Large Language Models: Fine-Tuning Techniques Using Survey Data, Davis P. Forster

Theses and Dissertations

Large language models (LLMs) are increasingly used to simulate responses of human demographic groups, a task known as silicon sampling. This paper investigates whether supervised fine-tuning can improve algorithmic fidelity in such settings. We construct a dataset from the General Social Survey (GSS), converting demographic attributes into natural-language backstories and randomly selecting one attribute as a held-out target. Fine-tuning a LLaMA-3.1-70B model on this dataset yields significant improvements on two tasks: (1) imputing missing attributes at the individual level, and (2) reproducing response distributions for demographic slices, such as racial and age groups. Notably, these improvements are achieved with minimal …


Cyber-Physical Framework For Smart Paint Manufacturing: Hybrid Integration Of Plc And Recipe Management Simulation, Stephen A. Michael, Anas M. Atieh, Emmanuel Nkwocha, Nathir A. Rawashdeh Dec 2025

Cyber-Physical Framework For Smart Paint Manufacturing: Hybrid Integration Of Plc And Recipe Management Simulation, Stephen A. Michael, Anas M. Atieh, Emmanuel Nkwocha, Nathir A. Rawashdeh

Michigan Tech Publications

This study investigates the implementation of Industry 4.0 paradigms in the context of smart paint manufacturing, focusing on process control and recipe management through the integration of Ignition SCADA, a Siemens programmable logic controller (PLC), and a MySQL Workbench database. The developed architecture employs Ignition as an interoperable communication interface that facilitates bidirectional data exchange between the PLC and the database, thereby establishing a cyber-physical system for automated monitoring and control. The digital recipe management module formalizes paint formulations into parameterized datasets specifying paint and solvent ingredient ratios, process variables, and operational constraints, which are executed autonomously by the control …


Microbial Communities Of Selected Regions Of The Deep Springs Lake Aquifer System, Rania Zaki, Emma Bourne, Andrew Storino, Jay Nadeau Dec 2025

Microbial Communities Of Selected Regions Of The Deep Springs Lake Aquifer System, Rania Zaki, Emma Bourne, Andrew Storino, Jay Nadeau

Physics Faculty Publications and Presentations

Deep Springs Lake is a small, isolated, highly alkaline soda lake in Inyo County of Eastern California, USA. It is a seasonally filled salt lake or playa, and is part of a closed aquifer system. Such closed systems are globally rare, occurring only in arid zones where annual evaporation is greater than annual rainfall. Deep Springs Lake’s hydrology and geology have been well studied, and it is home to a unique toad species, but its microbiome remains unexplored. Here we perform 16S, 18S, and ITS amplicon sequencing of the lake water, dried salt crust at the edges the lake, and …


Tests Without Borders: A Global Approach To Measuring Visualization Literacy, Olivia A. Guess Dec 2025

Tests Without Borders: A Global Approach To Measuring Visualization Literacy, Olivia A. Guess

McKelvey School of Engineering Graduate Student Theses & Dissertations

Visualization literacy assessments shape how we understand people's ability to interpret data, yet most existing instruments embed Western datasets and assumptions that limit their relevance for global audiences. This thesis argues that because data is personal, assessments must also be culturally grounded. We introduce a unified framework for adapting the Mini-VLAT into 22 regionally responsive short-form assessments, each retaining the structure of the original test while incorporating datasets and scenarios tailored to specific regions around the world. To demonstrate how such adaptations can be customized and validated, we present a detailed case study of a Ghana-adapted Mini-VLAT, developed in collaboration …


Parametric Control And Amplification In Superconducting Quantum Systems: From Entanglement Probes To Pt-Symmetric Architectures, Chandrashekhar Rao Gaikwad Dec 2025

Parametric Control And Amplification In Superconducting Quantum Systems: From Entanglement Probes To Pt-Symmetric Architectures, Chandrashekhar Rao Gaikwad

Arts & Sciences Graduate Student Theses and Dissertations

The precise control, entanglement, and measurement of quantum systems are central challenges in realizing scalable quantum information processing. This dissertation investigates how parametric modulation and engineered nonlinearity can be harnessed to both manipulate and measure superconducting qubits with high fidelity. In one part, controlled parametric drives are used to generate entanglement between qubit pairs and employ their joint states as probes of environmental dynamics. This approach enables the exploration of the non-Markovian nature of quantum environments, revealing how memory effects influence qubit coherence and energy relaxation. In a separate but conceptually related study, the same principle of parametric driving is …


Indigenizing Aquaculture: In Pursuit Of An Integrated Multi-Trophic Aquaculture System For Enhanced Self-Sufficiency In Akaroa Harbour, Aotearoa New Zealand, Cali R. Trainor Dec 2025

Indigenizing Aquaculture: In Pursuit Of An Integrated Multi-Trophic Aquaculture System For Enhanced Self-Sufficiency In Akaroa Harbour, Aotearoa New Zealand, Cali R. Trainor

Capstone Collection

This study assessed the feasibility of integrating two pre-existing aquaculture activities in Akaroa Harbour, Aotearoa New Zealand into an integrated multi-trophic aquaculture (IMTA) system. The cultivation of giant kelp (Macrocystis pyrifera) presents an opportunity to improve the sustainability of Chinook salmon (Oncorhynchus tshawytscha) farming by introducing alternative food sources for salmon, which can be used to produce fish feed locally, enhancing the self-sufficiency of the community and boosting the holistic efficiency of the system. Macroinvertebrates residing in giant kelp wrack were collected, identified, and quantified to determine if any of the Macrocystis-associated specimens could serve as …


Cv: Joseph Kozminski (Physics), Joseph Kozminski Dec 2025

Cv: Joseph Kozminski (Physics), Joseph Kozminski

Physics Department Faculty Curricula Vitae

No abstract provided.


Marine Heatwave Co-Occurrence Between Estuarine And Coastal Systems, Ricardo U. Nardi, Piero L. F. Mazzini, Ryan K. Walter Dec 2025

Marine Heatwave Co-Occurrence Between Estuarine And Coastal Systems, Ricardo U. Nardi, Piero L. F. Mazzini, Ryan K. Walter

Physics

Marine heatwaves (MHWs), prolonged periods of anomalously warm ocean temperatures, pose significant threats to marine ecosystems. While MHWs in coastal and estuarine systems have been studied separately, their spatial coherence remains significantly understudied. Here we analyze over 2 decades of high-frequency in situ temperature data from 54 stations across 20 U.S. estuaries and 13 coastal buoys to assess MHW co-occurrences. We find that estuarine and coastal MHWs co-occur only ∼21% of the time, a 57% decrease compared to co-occurrence within estuaries (∼49%). Maximum co-occurrence occurs at zero lag, suggesting synchronous synoptic-scale atmospheric forcing, likely via air–sea heat fluxes. Co-occurrence shows …


Cloud-Top Entrainment Instability In Marine Stratocumulus Clouds: Observational Evidence From Collocated Microphysical, Turbulence, And Radiation Measurements, Inyeob La, Raymond Shaw, Holger Siebert, André Ehrlich, Jae Min Yeom, Seong Soo Yum Dec 2025

Cloud-Top Entrainment Instability In Marine Stratocumulus Clouds: Observational Evidence From Collocated Microphysical, Turbulence, And Radiation Measurements, Inyeob La, Raymond Shaw, Holger Siebert, André Ehrlich, Jae Min Yeom, Seong Soo Yum

Michigan Tech Publications

Marine stratocumulus clouds (MSC) strongly influence Earth's radiation budget, yet the mechanisms governing the descent of entrainment-affected (diluted) parcels, and the relative roles of cloud-top entrainment instability (CTEI) and longwave radiative cooling (RC), remain debated. Using helicopter-borne observations from the ACORES campaign that combine high-resolution in situ vertical profiling with co-located remote sensing, we examine vertical variations of microphysics, thermodynamics, and the entrainment interfacial layer (EIL). When CTEI conditions were strongly met, inhomogeneous mixing (IM) traits appeared near cloud top and transitioned to homogeneous mixing (HM) traits deeper in the cloud layer, accompanied by localized elevations of cloud base, signatures …


Regio- And Stereoselective Halogenation By An Iron(Ii)- And 2-Oxoglutarate-Dependent Halogenase In The Biosynthesis Of Halogenated Nucleosides, Philip M. Palacios, Xiaoyun Li, Simahudeen Bathir Jaber Sathik Rifayee, Haoyu Tang, Tatyana Karabencheva-Christova, Christo Christov, Wei-Chen Chang, Yisong Guo Dec 2025

Regio- And Stereoselective Halogenation By An Iron(Ii)- And 2-Oxoglutarate-Dependent Halogenase In The Biosynthesis Of Halogenated Nucleosides, Philip M. Palacios, Xiaoyun Li, Simahudeen Bathir Jaber Sathik Rifayee, Haoyu Tang, Tatyana Karabencheva-Christova, Christo Christov, Wei-Chen Chang, Yisong Guo

Michigan Tech Publications

Iron(II)- and 2-oxoglutarate-dependent (Fe/2OG) enzymes have garnered strong research interest in past decades due to their ability to catalyze regio- and stereoselective C-H functionalization via a single reactive intermediate, the oxyferryl species. In addition to the hydroxylation reaction that is commonly observed, other reaction outcomes have also been discovered in Fe/2OG enzymes. Among them, halogenation has attracted much research effort with the goal of revealing the molecular determinants to favor halogenation over hydroxylation however, a full mechanistic picture is still missing. In this study, by investigating a recently identified Fe/2OG halogenase, AdeV, from the biosynthetic pathway of Adechlorin, we show, …


Is Ai Replacing Human Mental Health Professionals?, Michiko Ueda Dec 2025

Is Ai Replacing Human Mental Health Professionals?, Michiko Ueda

Population Health Research Brief Series

An increasing number of people are turning to generative artificial intelligence (AI) tools and AI-assisted chatbots to manage mental health concerns. This data slice presents findings from a national survey of U.S. adults aged 18-49 (N = 1,805) conducted in October 2025. Among respondents, 35.2% reported using AI tools more than once a week for mental health support. Among those who had ever seen a human mental health professional, 28.4% reported visiting human providers less often since beginning to use AI for the same purpose. The findings suggest that a subset of users may be using AI to replace, rather …


Predicting The Attitudes Towards Mathematical Modeling Of Primary Math Teachers: The Role Of Self-Efficacy And Motivation, Brenden Rawls Dec 2025

Predicting The Attitudes Towards Mathematical Modeling Of Primary Math Teachers: The Role Of Self-Efficacy And Motivation, Brenden Rawls

Doctoral Dissertations and Projects

The purpose of this non-experimental quantitative predictive correlational study was to investigate the extent to which efficacy for pedagogy in mathematics, efficacy for teaching mathematics content, effectance motivation in mathematics, years of experience, and access to statistics, data science, or mathematical modeling courses predict attitudes toward constructivist practices in mathematical modeling of Virginia primary school mathematics teachers. The goal of the research was to understand what affective characteristics support effective adoption Virginia's mathematics curriculum change. Higher levels of mathematics teacher self-efficacy have been associated with constructivist instructional practices and higher levels of student achievement. The sample included kindergarten through fifth-grade …


Testing For Dice Control At Craps, Stewart N. Ethier Dec 2025

Testing For Dice Control At Craps, Stewart N. Ethier

UNLV Gaming Research & Review Journal

Dice control involves “setting” the dice and then throwing them carefully, in the hope of influencing the outcomes and gaining an advantage at craps. How does one test for this ability? To specify the alternative hypothesis, we need a statistical model of dice control. Two have been suggested in the gambling literature, namely the Smith–Scott model and the Wong–Shackleford model. Both models are parameterized by θ ∈ [0, 1], which measures the shooter’s level of control. We propose and compare four test statistics: (a) the sample proportion of 7s; (b) the sample proportion of pass-line wins; (c) the sample mean …


The Mechanics And Consequences Of The Löwenheim-Skolem And Compactness Theorems, Adam Murphy Dec 2025

The Mechanics And Consequences Of The Löwenheim-Skolem And Compactness Theorems, Adam Murphy

Honors Program Theses and Projects

The compactness theorem for first-order logic says that for a set of first-order sen-tences to be satisfiable, it’s enough for every finite subset to be satisfiable. We’ll see how the compactness theorem arises from two methods of model construction: first by ultraproducts, and second by Henkin’s method of constructing models from constant symbols. We’ll explore several representative applications of compactness, such as how it can be used to demonstrate that a property is not expressible, establishing limitations on first-order expressibility. The Löwenheim-Skolem theorem says that if an infinite set Γ of first-order sentences has an infinite model, then for all …


Advancing Cybersecurity Practice: Explainable Machine Learning For Network Intrusion Detection, Adam Grabowski, Shengjie Xu Dec 2025

Advancing Cybersecurity Practice: Explainable Machine Learning For Network Intrusion Detection, Adam Grabowski, Shengjie Xu

Journal of Cybersecurity Education, Research and Practice

This research investigates explainable artificial intelligence (XAI) integration within machine learning (ML)-based intrusion detection systems (IDS), focusing on distinguishing malicious from benign network activities. We employed Random Forest and XGBoost models evaluated on widely recognized datasets, including NSL-KDD and UNSW-NB15, using both binary and multi-class classification tasks. The objective was to enhance cybersecurity operations through improved model transparency and interpretability. By integrating SHAP (SHapley Additive exPlanations) and LIME (Local Interpretable Model-Agnostic Explanations), the study offers comprehensive global and local insights into model decision-making processes. Results demonstrate SHAP's effectiveness in providing a broad, dataset-wide understanding of feature interactions and importance, while …


Cybercamp: An Experience Report On The Transformations Of An Intensive Cybersecurity Summer Camp For High School Students, Jose R. Ortiz Ubarri, Kariluz Dávila Diaz Ph.D., Rafael A. Arce Nazario Dec 2025

Cybercamp: An Experience Report On The Transformations Of An Intensive Cybersecurity Summer Camp For High School Students, Jose R. Ortiz Ubarri, Kariluz Dávila Diaz Ph.D., Rafael A. Arce Nazario

Journal of Cybersecurity Education, Research and Practice

The Cybercamp is a Cybersecurity summer camp for high school students that has been held for the last nine years at a Hispanic Serving Institution. Since its inception in 2016 the Cybercamp has undergone several transformations in response to budget reductions and the COVID pandemic, to finally become its current version: a rich, hands-on learning experience that we believe is easily replicable even in resource-challenged environments.

In this paper, we document the transformations of the Cybercamp and discuss the developed curriculum and materials in hopes that others will reuse, adapt, and improve upon them. In the Cybercamp, we apply active …


Patterns Of Llm Weaponization: A Comparative Analysis Of Exploitation Incidents Across Commercial Ai Systems, George Antoniou Dec 2025

Patterns Of Llm Weaponization: A Comparative Analysis Of Exploitation Incidents Across Commercial Ai Systems, George Antoniou

Faculty and Staff Publications & Presentations

This comparative study examines patterns of Large Language Model (LLM) weaponization through systematic analysis of four major exploitation incidents spanning 2023-2025. While existing research focuses on isolated incidents or theoretical vulnerabilities, this study provides the first comprehensive comparative framework analyzing exploitation patterns across state-sponsored cyber-espionage (Anthropic Claude incident), academic security research (GPT-4 autonomous privilege escalation), social engineering platforms (SpearBot phishing framework), and underground criminal commoditization (WormGPT/FraudGPT ecosystem). Through comparative analysis across eight dimensions—adversary sophistication, target selection, exploitation techniques, autonomy levels, detection evasion, attribution challenges, defensive gaps, and capability democratization—this research identifies critical cross-case patterns informing defensive prioritization. Findings reveal three …


Reconstructing Central American Hydroclimate Changes Across Time From Isotopic Signatures In Modern And Paleo-Rainfall Records, Giuseppe Lucia Dec 2025

Reconstructing Central American Hydroclimate Changes Across Time From Isotopic Signatures In Modern And Paleo-Rainfall Records, Giuseppe Lucia

UNLV Theses, Dissertations, Professional Papers, and Capstones

Tropical monsoon rainfall is a key component of Earth’s climate system and supports the livelihood and economy of billions of people. Yet, projections of future monsoons remain highly uncertain, particularly in regions with distinct physiography and complex land-ocean-atmosphere interactions like Central America, where long and continuous high-resolution paleoclimate data to test climate model simulations are still limited. This series of studies aims to reconstruct monsoon dynamics and underlying forcing controls in Central America on multiple timescales by the analysis and integration of stable isotope data in modern and paleo-rainfall records from Guatemala.

In Chapter 2, I present a daily-resolution, two-year-long …


A Comparison Of Airborne Tree Pollen In The Las Vegas Valley From 2017 – 2021, Asma Tahir Dec 2025

A Comparison Of Airborne Tree Pollen In The Las Vegas Valley From 2017 – 2021, Asma Tahir

UNLV Theses, Dissertations, Professional Papers, and Capstones

Airborne pollen are a predominant cause of asthma, allergic disease, and respiratory infections. The strong allergenic potential of tree pollen is of a public health concern. Several allergenic trees grow in the Mojave Desert, but not all are native to the region. Concentrations of airborne tree pollen are affected by atmospheric, environmental, ecological, and geospatial factors. Previous research has reported high tree pollen concentrations in the Las Vegas Valley, but long-term comparison studies are lacking. This study measured and compared tree pollen concentrations from five different collection stations in Las Vegas. Pollen samples collected from January 1, 2017, to December …


Insights From The Evolution Of Transport Technologies, 1800–2020: Energy Use, Transitions, And Efficiency, Bernardo Tostes, Matthew Kuperus Heun, Sofia T. Henriques, Paul E. Brockway, Tânia Sousa Dec 2025

Insights From The Evolution Of Transport Technologies, 1800–2020: Energy Use, Transitions, And Efficiency, Bernardo Tostes, Matthew Kuperus Heun, Sofia T. Henriques, Paul E. Brockway, Tânia Sousa

University Faculty Publications and Creative Works

The replacement of fossil fuels by electricity and other alternative fuels in transport will not be that sector’s first energy transition. Using transport history as an analogue for the future can offer helpful insights for today’s policymakers. The present work investigates the evolution of world energy use in the transport sector, identifying its energy transitions (at the final and useful stages), and evaluating the impact of past transitions on energy use over the period 1800–2020. To perform these analyses, a novel long-run dataset of energy use and efficiencies of water, rail, road, and air transport was developed. Our main findings …


Stability Analysis Of Thermohaline Convection With A Time-Varying Shear Flow Using The Lyapunov Method, Kalin Kochnev Dec 2025

Stability Analysis Of Thermohaline Convection With A Time-Varying Shear Flow Using The Lyapunov Method, Kalin Kochnev

Honors Scholar Theses

This work applies the Lyapunov method to identify instabilities and compute the growth rate of a linear time-varying system. The linear system studied describes cold fresh water on top of hot salty water with a periodically time-varying background shear flow. A time-dependent weighting matrix is employed to construct a Lyapunov function candidate. The resulting linear matrix inequalities are discretized in time using the forward Euler method. As the number of temporal discretization points increases, the growth rate predicted by the Lyapunov method or Floquet theory, used for comparison, will converge to the same value obtained from numerical simulations. Furthermore, the …


There Is No Obstruction To A Euclidean Proof For The Fourth Postulate, José Gil-Férez, Piotr Błaszczyk, M. Andrew Moshier, Alberto Naibo, Jean-Michel Salanskis Dec 2025

There Is No Obstruction To A Euclidean Proof For The Fourth Postulate, José Gil-Férez, Piotr Błaszczyk, M. Andrew Moshier, Alberto Naibo, Jean-Michel Salanskis

Mathematics, Physics, and Computer Science Faculty Articles and Research

In Gil-Férez et al. (2025), we presented a proof of Postulate 4 using purely Euclidean techniques, against which Blåsjö (2025) raised several objections. In this note, we offer linguistic, textual, historical, and mathematical evidence that demonstrate that all these objections are baseless.


Analysis Of Leakage In Nearshore Pipelines Using Fitness For Service Method To Ensure Mechanical Integrity Based On Api-579 Level 3, Elriandri Elriandri, Dedi Priadi Dec 2025

Analysis Of Leakage In Nearshore Pipelines Using Fitness For Service Method To Ensure Mechanical Integrity Based On Api-579 Level 3, Elriandri Elriandri, Dedi Priadi

Journal of Materials Exploration and Findings

The Fitness for Service (FFS) analysis is performed as a quantitative assessment to evaluate the integrity condition of a pipeline. Essentially, FFS assessment helps determine whether equipment components can operate safely despite existing deficiencies. This evaluation is carried out using the Finite Element Method (FEM). In the case of an underwater pipeline that experiences leak due to anchor pull at the flange connection, it undergoes plastic deformation and is lifted approximately 1 meter. As a mitigation step, inspection and repairs have been carried out by the company. Subsequently, modeling is performed to reconstruct the deformation process of the pipeline. Then, …


Re: Approval Letter For The Revised Draft Final Annual Operations And Maintenance (O&M) Report: Butte Treatment Lagoon (Btl) System - 2023 (Dated October 29, 2025), Emma Rott Dec 2025

Re: Approval Letter For The Revised Draft Final Annual Operations And Maintenance (O&M) Report: Butte Treatment Lagoon (Btl) System - 2023 (Dated October 29, 2025), Emma Rott

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.