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Daniel J. O'Brien

Publications and source records attributed to Daniel J. O'Brien.

3 recordsLinked to original sources

Evaluating Learning of Motion Graphs with a LiDAR-Based Smartphone Application

Data modeling and graphing skill sets are foundational to science learning and careers, yet students regularly struggle to master these basic competencies. Further, although educational researchers have uncovered numerous approaches to support sense-making with mathematical models of motion, teachers sometimes struggle to enact them due to a variety of reasons, including limited time and materials for lab-based teaching opportunities and a lack of awareness of student learning difficulties. In this paper, we introduce a free smartphone application that uses LiDAR data to support motion-based physics learning with an emphasis on graphing and mathematical modeling. We tested the embodied technology, called LiDAR Motion, with 106 students in a non-major, undergraduate physics classroom at a mid-sized, private university on the U.S. East Coast. In identical learning assessments issued both before and after the study, students working with LiDAR Motion improved their scores by a more significant margin than those using standard issue sonic rangers. Further, per a voluntary survey, students who used both technologies expressed a preference for LiDAR Motion. This mobile application holds potential for improving student learning in the classroom, at home, and in alternative learning environments.

physics.ed-ph↗

Feynman, Lewin, and Einstein Download Zoom: A Guide for Incorporating E-Teaching of Physics in a Post-COVID World

Distance education has expanded significantly over the last decade, but the natural sciences have lagged in the implementation of this instructional mode. The abrupt onset of the COVID-19 pandemic left educational institutions scrambling to adapt curricula to distance modalities. With projected effects lasting through the 2020--21 academic year, this problem will not go away soon. Analysis of the literature has elucidated the costs and benefits of, as well as obstacles to, the implementation of e-learning, with a focus on undergraduate physics education. Physics faculty report that a lack of time to learn about research-driven innovation is their primary barrier to implementing it. In response, this paper is intended to help physics lecturers and lab instructors re-think their courses now that distance learning is far more prevalent due to the pandemic. This paper serves as an all-in-one guide of recommendations for successful distanced educational practices, with an emphasis on smartphones and social media. These technologies were chosen for their utility in a virtual environment. Additionally, this paper can be used as a resource for university administrators to adapt to the changing needs associated with new teaching modalities.

physics.ed-ph↗

Systematic Characterization of Hydrophilized Polydimethylsiloxane

Flexible microfluidics have found extensive utility in the biological and biomedical fields. A leading substrate material for compliant devices is polydimethylsiloxane (PDMS). Despite its many advantages, PDMS is inherently hydrophobic and consequently its use in passive (pumpless) microfluidics becomes problematic. To this end, many physical and chemical modifications have been introduced to render PDMS hydrophilic, ranging from amphiphilic molecule additions to surface plasma treatments. However, when transitioning from lab benchtop to realized medical devices, these modifications must exhibit long-term stability. Unfortunately, these modifications are often presented but their mechanisms and long-term stability are not studied in detail. We have investigated an array of PDMS modifications, utilizing contact angle goniometry to study surface energy over a 30-day evolution study. Samples were stored in air and water, and Fourier Transform Infrared-Attenuated Total Reflectance (FTIR-ATR) analysis was used to confirm surface functional group uniformity. We have identified preferred modification techniques for long-lasting PDMS devices and characterized often overlooked material stability.

physics.app-ph↗