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1. Derivation of the ion equation

   Grenier, E ( March 2020 , Quarterly of applied mathematics)

   We consider the classical Euler-Poisson system for electrons and ions, interacting through an electrostatic field. The mass ratio of an electron and an ion is small and we establish an asymptotic expansion of solutions, where the main term is obtained from a solution to a self-consistent equation involving only the ion variables. Moreover, on R^3, the validity of such an expansion is established even with \ill-prepared" Cauchy data, by including an additional initial layer correction. 

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2. Derivation of the ion equation

   https://doi.org/https://doi.org/10.1090/qam/1558  

   E. Grenier, Y. Guo ( September 2019 , Quarterly of applied mathematics)

   We consider the classical Euler-Poisson system for electrons and ions, interacting through an electrostatic field. The mass ratio of an electron and an ion $ m_e/M_i\ll 1$ is small and we establish an asymptotic expansion of solutions, where the main term is obtained from a solution to a self-consistent equation involving only the ion variables. Moreover, on $ \mathbb{R}^3$, the validity of such an expansion is established even with ``ill-prepared'' Cauchy data, by including an additional initial layer correction. 

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3. Culturally-based Ethical Barriers for American Indian/Alaska Native Students and Professionals in Engineering

   https://doi.org/10.18260/1-2--36888  

   Ingram, Jani ; Castagno, Angelina ; Camplain, Ricky ; Blackhorse, Davona ( September 2022 , 2021 ASEE Virtual Annual Conference Content Access)

   Prior research suggests various reasons for the paucity of American Indian/Alaska Native (AI/AN) people in engineering fields, including academic deficiencies, lack of role models, and minimal financial support to pursue a college education. One potential reason that has yet to be explored relates to the cultural and spiritual barriers that could deter AI/AN people from feeling a sense of belonging in engineering fields. These barriers may create obstacles to progressing through engineering career pathways. Our research investigates the range and variation of cultural/spiritual/ethical issues that may be affecting AI/AN people’s success in engineering and other science, technology, and mathematics fields. The work reported here focuses on findings from students and professionals in engineering fields specifically. The study seeks to answer two research questions: (1) What ethical issues do AI/AN students and professionals in engineering fields experience, and how do they navigate these issues?, and (2) Do ethical issues impede AI/AN students from pursuing engineering careers, and if so, how? We distributed an online survey to AI/AN college students (undergraduate and graduate) and professionals in STEM fields, including engineers, in the western United States region. Our results indicate strong connections to AI/AN culture by the participants in the study as well as some cultural, ethical, and/or spiritual barriers that exist for AI/AN individuals in the engineering field. The AI/AN professionals had less concerns with respect to activities that may conflict with AI/AN cultural customs compared to the students, which may be a result of the professionals having gained experiences that allow them to navigate these situations. Overall, our research offers insights for policy and practice within higher education institutions with engineering majors and/or graduate programs and organizations that employ engineering professionals. 

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4. Culturally-based Ethical Barriers for American Indian/Alaska Native Students and Professionals in Engineering

   J. C. Ingram, A. E. ( January 2021 , 2021 ASEE Conference & Exhibition)

   Qin Zhu, PhD Assistant Professor (Ed.)

   Prior research suggests various reasons for the paucity of American Indian/Alaska Native (AI/AN) people in engineering fields, including academic deficiencies, lack of role models, and minimal financial support to pursue a college education. One potential reason that has yet to be explored relates to the cultural and spiritual barriers that could deter AI/AN people from feeling a sense of belonging in engineering fields. These barriers may create obstacles to progressing through engineering career pathways. Our research investigates the range and variation of cultural/spiritual/ethical issues that may be affecting AI/AN people’s success in engineering and other science, technology, and mathematics fields. The work reported here focuses on findings from students and professionals in engineering fields specifically. The study seeks to answer two research questions: (1) What ethical issues do AI/AN students and professionals in engineering fields experience, and how do they navigate these issues?, and (2) Do ethical issues impede AI/AN students from pursuing engineering careers, and if so, how? We distributed an online survey to AI/AN college students (undergraduate and graduate) and professionals in STEM fields, including engineers, in the western United States region. Our results indicate strong connections to AI/AN culture by the participants in the study as well as some cultural, ethical, and/or spiritual barriers that exist for AI/AN individuals in the engineering field. The AI/AN professionals had less concerns with respect to activities that may conflict with AI/AN cultural customs compared to the students, which may be a result of the professionals having gained experiences that allow them to navigate these situations. Overall, our research offers insights for policy and practice within higher education institutions with engineering majors and/or graduate programs and organizations that employ engineering professionals 

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5. Interval Signal Temporal Logic From Natural Inclusion Functions

   https://doi.org/10.1109/LCSYS.2023.3337744  

   Baird, Luke ; Harapanahalli, Akash ; Coogan, Samuel ( January 2023 , IEEE Control Systems Letters)

   We propose an interval extension of Signal Temporal Logic (STL) called Interval Signal Temporal Logic (I-STL). Given an STL formula, we consider an interval inclusion function for each of its predicates. Then, we use minimal inclusion functions for the min and max functions to recursively build an interval robustness that is a natural inclusion function for the robustness of the original STL formula. The resulting interval semantics accommodate, for example, uncertain signals modeled as a signal of intervals and uncertain predicates modeled with appropriate inclusion functions. In many cases, verification or synthesis algorithms developed for STL apply to I-STL with minimal theoretic and algorithmic changes, and existing code can be readily extended using interval arithmetic packages at negligible computational expense. To demonstrate I-STL, we present an example of offline monitoring from an uncertain signal trace obtained from a hardware experiment and an example of robust online control synthesis enforcing an STL formula with uncertain predicates. 

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