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The wavelength dependence of atmospheric absorption creates range cues in hyperspectral measurements that can be exploited for passive ranging using only thermal emissions. In this work, we present fundamental limits on absorption-based ranging under a model of known air temperature and wavelength-dependent attenuation coefficient, with object temperature and emissivity unknown; reflected solar and environmental radiance is omitted from our analysis. Fisher information computations illustrate how performance limits depend on atmospheric conditions such as air temperature and humidity; temperature contrast in the scene; spectral resolution of measurement; and distance. These results should prove valuable in sensor system design.

 

It is well established that access to social supports is essential for engineering students’ persistence and yet access to supports varies across groups. Understanding the differential supports inherent in students’ social networks and then working to provide additional needed supports can help the field of engineering education become more inclusive of all students. Our work contributes to this effort by examing the reliability and fairness of a social capital instrument, the Undergraduate Supports Survey (USS). We examined the extent to which two scales were reliable across ability levels (level of social capital), gender groups and year-in-school. We conducted two item response theory (IRT) models using a graded response model and performed differential item functioning (DIF) tests to detect item differences in gender and year-in-school. Our results indicate that most items have acceptable to good item discrimination and difficulty. DIF analysis shows that multiple items report DIF across gender groups in the Expressive Support scale in favor of women and nonbinary engineering students. DIF analysis shows that year-in-school has little to no effect on items, with only one DIF item. Therefore, engineering educators can use the USS confidently to examine expressive and instrumental social capital in undergraduates across year-in-school. Our work can be used by the engineering education research community to identify and address differences in students’ access to support. We recommend that the engineering education community works to be explicit in their expressive and instrumental support. Future work will explore the measurement invariance in Expressive Support items across gender. 

This work-in-progress (WIP) paper aims to elucidate how students have developed professional skills since the onset of the COVID-19 pandemic and who are the people who have provided skill development opportunities. Because of the way social distancing affected engineering education during the pandemic, developing professional skills may have been a challenge for engineering students. While online courses and virtual meetings allowed students to remain in contact with faculty and each other, the opportunities to continue having deep relationships (i.e., strong ties) were sparse. Our paper presents an early look at findings from the qualitative phase of an explanatory mixed methods study conducted with 1,234 undergraduates from 13 schools in the US. Our ongoing thematic qualitative analysis reveals that the changes that accompanied social distancing and periods of emergency remote teaching caused by COVID-19 have reinforced different opportunities to develop professional skills than prior to the pandemic. While some students expressed they had fewer opportunities to develop professional skills, participants also identified opportunities to (1) hone written communication skills when inperson discussions were reduced and (2) leverage knowledge from family members to continue developing professionally. Our next steps include finishing the qualitative analysis phase of the project and mixing the qualitative and quantitative data to develop overarching findings that the engineering education community can use to understand how students’ professional skills develop and how to promote that development even during times of educational disruption. 

The purpose of our poster presentation is two-fold: 1) to provide an overview of our NSF project, Pandemic Impact: Undergraduates’ Social Capital and Engineering Professional Skills, and 2) to report our progress and preliminary quantitative findings. We hope to discuss our project and preliminary results with fellow engineering educators and receive feedback. The COVID-19 pandemic has impacted engineering education in multiple ways that will continue to be felt for years to come. One of the less understood ways the pandemic has continued to leave a residue on engineering education is how social distancing and online courses altered students’ professional development. Of particular concern are students who were either new to the institution or started their college education during the pandemic. These students have potentially limited opportunities to establish social relationships at their educational institutions compared to students who already developed such relationships when the pandemic-induced online learning took place. The differences in students’ social relationships can have other, more profound impacts on their undergraduate engineering experiences. Research has shown that students’ social relationships provide them with connections to resources and supports essential for navigating an engineering program and help them obtain more opportunities to practice non-technical professional skills [1], [2]. Although social distancing measures diminished and students returned primarily to in-person, the pandemic has altered the development of engineering students in ways not understood. In particular, understanding the nature of students’ social interactions on campus and the types of opportunities for professional development is essential so that instructors and campus staff can respond to the developmental needs of students. As a result, the overarching research question for our project is: How do engineering undergraduates leverage relationships (operationalized as social capital) to gain opportunities to develop professional skills? 

The East Antarctic Ice Sheet (EAIS) has its origins ca. 34 million years ago. Since then, the impact of climate change and past fluctuations in the EAIS margin has been reflected in periods of extensive vs. restricted ice cover and the modification of much of the Antarctic landscape. Resolving processes of landscape evolution is therefore critical for establishing ice sheet history, but it is rare to find unmodified landscapes that record past ice conditions. Here, we discover an extensive relic pre-glacial landscape preserved beneath the central EAIS despite millions of years of ice cover. The landscape was formed by rivers prior to ice sheet build-up but later modified by local glaciation before being dissected by outlet glaciers at the margin of a restricted ice sheet. Preservation of the relic surfaces indicates an absence of significant warm-based ice throughout their history, suggesting any transitions between restricted and expanded ice were rapid.

 

Changes in dopaminergic neuromodulation play a key role in adult memory decline. Recent research has also implicated noradrenaline in shaping late-life memory. However, it is unclear whether these two neuromodulators have distinct roles in age-related cognitive changes. Here, combining longitudinal MRI of the dopaminergic substantia nigra–ventral tegmental area (SN-VTA) and noradrenergic locus coeruleus (LC) in younger (n = 69) and older (n = 251) adults, we found that dopaminergic and noradrenergic integrity are differentially associated with memory performance. While LC integrity was related to better episodic memory across several tasks, SN-VTA integrity was linked to working memory. Longitudinally, we found that older age was associated with more negative change in SN-VTA and LC integrity. Notably, changes in LC integrity reliably predicted future episodic memory. These differential associations of dopaminergic and noradrenergic nuclei with late-life cognitive decline have potential clinical utility, given their degeneration in several age-associated diseases.

 

Evolution in time-varying environments naturally leads to adaptable biological systems that can easily switch functionalities. Advances in the synthesis of environmentally responsive materials therefore open up the possibility of creating a wide range of synthetic materials which can also be trained for adaptability. We consider high-dimensional inverse problems for materials where any particular functionality can be realized by numerous equivalent choices of design parameters. By periodically switching targets in a given design algorithm, we can teach a material to perform incompatible functionalities with minimal changes in design parameters. We exhibit this learning strategy for adaptability in two simulated settings: elastic networks that are designed to switch deformation modes with minimal bond changes and heteropolymers whose folding pathway selections are controlled by a minimal set of monomer affinities. The resulting designs can reveal physical principles, such as nucleation-controlled folding, that enable such adaptability.