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Bats and Bridges: What You Need to Know
Get PDFBats’ use of bridges is well documented. With more bat species being added to the endangered species list, this is a significant issue for maintenance, rehabilitation, and replacement. From defining bat species using specific bridges to monitoring bat use through in-depth analysis, several techniques can facilitate USFWS coordination and ensure negative impacts to endangered species are avoided or minimized throughout transportation improvements. This session will detail these techniques and approaches and educate transportation planners on best practices
Portland Airport Runway Extension: Challenges and Successes
Get PDFA runway extension at the Portland Airport was recently opened to traffic and was the culmination of well over a decade of effort. The project presented numerous engineering challenges beyond design, such as environmental approval, land acquisition, and ditch mitigation. Phase I required the enclosure of Alexander Ditch and substantial soil for grading the site. Phase II included the paving and lighting of the runway and taxiway extensions. Join us for a discussion of this project
Coronal Mass Ejections
Get PDFThe underlying dynamics of solar processes are a topic of considerable interest, because the events on the surface of the Sun directly affect the environment of our planet. Certain ‘storms’ that erupt in the outer layers of the Sun can propel masses of electrically charged plasma into the solar system. If the path of that material crosses Earth’s orbit, it can disrupt our societal electronic and satellite resources. Observing and analyzing these events is a first step toward predicting them and hardening our equipment against them. This work reviews how solar scientists collect and view this data on coronal mass ejections
Constraining the Binding Problem Using Maps
Get PDFWe constrained the binding problem by creating maps of different attributes. We compared the performance of different models with different maps in our current study. Our preliminary results showed that the performance of the model is the highest when location maps were used. These results suggest that the optimal way to constrain the binding problem is to create location maps of different attributes
The Model 2.0 and Friends: An Interim Report
Get PDFLast year, I reported on preliminary results of an anatomically-inspired deep learning model of the visual system and its role in explaining the face inversion effect. This year, I will report on new results and some variations on network architectures that we have explored, mainly as a way to generate discussion and get feedback. This is by no means a polished, final presentation!
We look forward to the group’s suggestions for these projects
Task-driven influences on fixational eye movements
Get PDFThere is now compelling evidence that the spatiotemporal remapping carried out by fixational eye movements (FEMs) is an essential step in visual processing. Moreover, the overall Brownian-like statistics of FEMs are calibrated to map fine spatial detail into the temporal frequency range to which retinal circuitry is tuned. Here, we tested the hypothesis that the detailed spatial characteristics of FEMs can be adjusted to task demands via cognitive influences that operate even in the absence of a visual stimulus. We examined FEMs in a task that required subjects (N=6) to report which of two letters was displayed. Trials were blocked; in each block, the letter pair was known in advance: H vs. N or E vs. F. The task was demanding: letters were 1.5 deg and embedded in 1/f noise, and had a contrast that yielded ~75% correct performance. Note that the HN discrimination could be accomplished by identification of either a horizontal or oblique contour, but the EF discrimination required identification of a horizontal contour. Thus, in the EF blocks, only a vertical ocular drift would be expected to maximize the neural signal. For each condition, FEM velocity statistics, which were approximately Gaussian, were characterized by their covariance. As predicted, the ratio of velocity variance in the vertical vs. oblique direction was greater in EF trials than in HN trials. This difference was greater when no stimulus was present (20% of trials in each block), indicating open-loop control. We also found that single-trial drift trajectories could be decoded by a simple decoder to identify the task (HN vs. EF) at above-chance levels in most subjects. While the observed covariance patterns showed substantial inter-subject variability, we found that a single transformation, applied with subject-specific strengths, could largely account for all subjects’ findings. Critically, this shared transformation acts holistically on the plane, rather than individually on horizontal and vertical axes. In sum, we find that knowledge of the specific requirements of a visual task exerts fine-tuned open-loop control over ocular drifts, and we characterize the nature of this control
Toward Excellence with Equity: Role of Mathematics Self-Efficacy in Enhancing Mathematics Achievement
No full textThis dissertation researched the scope of mathematics achievement disparities in the United States and how these disparities can be minimized through a self-efficacy lens. To answer pertinent research questions with data from the National Assessment of Educational Progress (NAEP) 2019 mathematics assessment in Grades 4, 8, and 12, gap analyses, two-level cross-sectional multilevel modeling, and two-level structural equation modeling were conducted. The discoveries demonstrated that the excellence gaps in U.S. in mathematics achievement by race/ethnicity, gender, NSLP, ELL, and IEP persisted and widened from Grade 4 to Grade 8 yet decreased at Grade 12. Self-efficacy was a noteworthy predictor of students’ mathematics achievement, displaying large effect sizes across grades. The disparities in mathematics achievement by student subgroups lessened when students\u27 self-efficacy was equal. Moreover, self-efficacy mediated the relationships between mastery-approach goals, performance-approach goals, interest, persistence in learning and achievement. Additional results demonstrated that the status of being racially/ethnically underrepresented students partially moderated the connections between motivational variables and mathematics achievement. School locale and the percentage of underrepresented students significantly impacted students’ achievement. This dissertation underscores the importance of self-efficacy in closing mathematics achievement gaps and improving students’ mathematics achievement