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This paper addresses the critical knowledge gap in the structural performance of porcelain insulators in overhead railway power systems through experimental evaluations. The focus is on porcelain insulators as part of a contact wire registration assembly (CWRA) in the railway power system. While porcelain insulators are the most widely used high-voltage insulator material, no previous studies have investigated the impact of age on their ultimate load capacity in overhead rail systems. The paper presents the experimental design for tension and a novel 45-degree test setup that replicates field conditions, as well as an overview of the test specimens, which were both new and retired from the field. The results indicate that aging has no impact on the strength of insulators in direct tension tests, but retired insulators in the CWRA show a reduced capacity. Additionally, the location of the drop bracket has a notable influence on the failure mode and stiffness of the assembly. The findings contribute to future improvements in system design and performance. Future research should include material testing, finite element studies, and dynamic testing of the full CWRA setup to further understand insulator performance and support resilient power transmission and distribution systems. Additionally, similar tests should be conducted on polymeric insulators, due to their prevalence. [ABSTRACT FROM AUTHOR]

Concrete-filled fiber-reinforced polymer (FRP) tubes (CFFTs) offer an alternative to traditional reinforced concrete columns for new construction applications due to their high strength, ductility, and corrosion resistance properties. Despite their popularity, there is a lack of accurate analytical models for the cyclic/seismic performance of CFFT columns. This is due to the absence of precise stress–strain models for FRP tubes and confined concrete under cyclic loading. Previous experiments on CFFT columns suggest that even minimal reinforcement (≤1%) provides essential energy dissipation for extreme events. However, existing stress–strain models for FRP-confined concrete often neglect the contribution of longitudinal and transverse steel reinforcement. While some researchers have proposed material models to address this issue, the analytical modeling of confinement effects from both steel reinforcement and FRP tubes, especially under lateral cyclic loading, continues to pose a significant challenge. This study aims to use previously collected experimental data to evaluate current analytical modeling approaches in OpenSeesPy3.5.1.12 to simulate the lateral cyclic behavior of CFFT columns with ±55° glass fiber-reinforced polymer (GFRP) fiber orientation. Both the lumped inelasticity and the distributed inelasticity modeling approaches are applied. The performance of various FRP confinement models is compared. The effect of plastic hinge length is also considered in the lumped plasticity approach. The findings suggest that integrating a fiber element section into the plastic hinge zone enhances the efficiency of the distributed inelasticity approach. This method accurately captures the non-linear behavior in the critical region and precisely predicts the shape of the hysteretic curve, all while reducing computational costs. Conversely, the lumped inelasticity modeling approach effectively forecasts energy dissipation and peak load values across the entire cyclic hysteresis curve, offering significant computational savings. Finally, a generalized modeling methodology for predicting the response of CFFTs under cyclic lateral load is proposed and subsequently validated using experimental results found in the existing literature. [ABSTRACT FROM AUTHOR]

Introduction: Despite efforts to increase the participation of marginalized students in Science, Technology, Engineering, and Mathematics (STEM), neurodivergent students have remained underrepresented and underserved in STEM graduate programs. This qualitative study aims to increase understanding of the experiences of neurodivergent graduate students pursuing advanced degrees in STEM. In this analysis, we consider how common graduate school experiences interface with the invisibility of neurological diversity, thus contributing to a set of unique challenges experienced by neurodivergent students. Materials and methods: In this qualitative study, 10 focus group sessions were conducted to examine the experiences of 18 students who identify as neurodivergent in graduate STEM programs at a large, research-intensive (R1) university. We used thematic analysis of the transcripts from these focus groups to identify three overarching themes within the data. Results: The findings are presented through a novel model for understanding neurodivergent graduate STEM student experiences. The findings suggest that students who identify as neurodivergent feel pressure to conform to perceived neurotypical norms to avoid negative perceptions. They also may self-silence to maintain stability within the advisor-advisee relationship. The stigma associated with disability labels contributes a heavy cognitive and emotional load as students work to mask neurodiversity-related traits, navigate decisions about disclosure of their neurodivergence, and ultimately, experience significant mental health challenges and burnout. Despite these many challenges, the neurodivergent graduate students in this study perceived aspects of their neurodivergence as a strength. Discussion: The findings may have implications for current and future graduate students, for graduate advisors who may or may not be aware of their students' neurodivergence, and for program administrators who influence policies that impact the wellbeing and productivity of neurodivergent students. [ABSTRACT FROM AUTHOR]

The ability to predict spatial elements based on twodimensional figures, evaluate engineering elements, identify expected deformations, and predict possible failure mechanisms are critical for engineers. However, in applied mechanics courses, many undergraduate engineering students struggle with applying these skills to engineering problems. Previous studies have shown that three-dimensional (3D) visualization can help students to improve spatial understanding, learn material more permanently, and improve their creativity. Building on this phenomenon, interactive 3D models using Augmented Reality (AR) were incorporated in a Mechanics of Materials course. This course is an entry-level course and major requirement for different engineering disciplines including Civil, Mechanical, Biomedical, Materials Science, and Manufacturing Engineering. To evaluate the effectiveness of 3D models in students' performance, a study was conducted with students in the course. In the study, one group only had access to a traditional, two-dimensional (2D) schematic, while the other group had access to a 3D model. The experimental and control groups were then swapped for the second problem. The results of this study revealed that 3D models improve student performance. This paper reviews the design and results from the study, with the expectation that showing the impact on students' performance will help institutions add similar activities to their engineering courses to improve students learning. [ABSTRACT FROM AUTHOR]

While a large body of literature suggests that students with Attention Deficit Hyperactivity Disorder (ADHD) possess significant creative and risk-taking potential, they remain highly underrepresented in engineering programs. High school students with ADHD have significantly lower GPAs and are over eight times more likely to drop out than their peers without ADHD, which makes them significantly less likely to enter college engineering programs. To support the development of a more diverse engineering pipeline, this work summarizes outreach efforts to high school and middle school students with ADHD with the intention of boosting self-esteem and increasing interest in engineering. [ABSTRACT FROM AUTHOR]