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Additive manufacturing (AM) is prevalent in academic, industrial, and layperson use for the design and creation of objects via joining materials together in a layer upon layer fashion. However, few universities have an undergraduate course dedicated to it. Thus, using NSF IUSE support [grant number redacted for review] from the Exploration and Design Tier of the Engaged Student Learning Track, this project has created and implemented such a course at three large universities: Texas Tech (a Carnegie high research productivity and Hispanic Serving Institution), Kansas State (a Carnegie high research productivity and land grant university) and California State, Northridge (the largest of all the California State campuses and highly ranked in serving underprivileged students). Our research team includes engineering professors and a sociologist trained in assessment and K-12 outreach to determine the effects of the course on the undergraduate and high school students. We are currently in year two of the three years of NSF support. 

This NSF IUSE project is on the Exploration and Design Tier and the Engaged Student Learning Track. It is aimed at better preparing the country’s professional workforce in the renaissance of U.S. skilled manufacturing by creating new personnel proficient in additive manufacturing (AM). AM is mainstream; it has the potential to bring jobs back to the U.S. and add to the nation’s global competitiveness. AM is the process of joining materials to make objects from 3D data in a layer upon layer fashion. The objectives are to develop, assess, revise, and disseminate an upper division course and laboratory, “Additive Manufacturing,” and to advance undergraduate and K-12 student research and creative inquiry activities as well as faculty expertise at three diverse participating universities: Texas Tech, California State Northridge, and Kansas State. This research/pedagogical team contains a mechanical engineering professor at each university to develop and teach the course, as well as a sociologist trained in K-12 outreach, course assessment, and human subjects research to accurately determine the effects on K-12 and undergraduate students. The proposed course will cover extrusion-based, liquid-based, and powder-based AM processes. For each technology, fundamentals, applications, and advances will be discussed. Students will learn solutions to AM of polymers, metals, and ceramics. Two lab projects will be built to provide hands-on experiences on a variety of state-of-the-art 3D printers. To stimulate innovation, students will design, fabricate, and measure test parts, and will perform experiments to explore process limits and tackle real world problems. They will also engage K-12 students through video demonstrations and mentorship, thus developing presentation skills. Through the project, different pedagogical techniques and assessment tools will be utilized to assess and improve engineering education at both the undergraduate and K-12 levels through varied techniques: i) undergraduate module lesson plans that are scalable to K-12 levels, ii) short informational video lessons created by undergraduates for K-12 students with accompanying in-person mentorship activities at local high schools and MakerSpaces, iii) pre- and post-test assessments of undergraduates’ and K-12 participating students’ AM knowledge, skills, and perceptions of self-efficacy, and iv) focus groups to learn about student concerns/learning challenges. We will also track students institutionally and into their early careers to learn about their use of AM technology professionally. 

Abstract We present UV and/or optical observations and models of SN 2023ixf, a type II supernova (SN) located in Messier 101 at 6.9 Mpc. Early time (flash) spectroscopy of SN 2023ixf, obtained primarily at Lick Observatory, reveals emission lines of Hi, Hei/ii, Civ, and Niii/iv/vwith a narrow core and broad, symmetric wings arising from the photoionization of dense, close-in circumstellar material (CSM) located around the progenitor star prior to shock breakout. These electron-scattering broadened line profiles persist for ∼8 days with respect to first light, at which time Doppler broadened the features from the fastest SN ejecta form, suggesting a reduction in CSM density atr≳ 10¹⁵cm. The early time light curve of SN 2023ixf shows peak absolute magnitudes (e.g.,M_u= −18.6 mag,M_g= −18.4 mag) that are ≳2 mag brighter than typical type II SNe, this photometric boost also being consistent with the shock power supplied from CSM interaction. Comparison of SN 2023ixf to a grid of light-curve and multiepoch spectral models from the non-LTE radiative transfer codeCMFGENand the radiation-hydrodynamics codeHERACLESsuggests dense, solar-metallicity CSM confined tor= (0.5–1) × 10¹⁵cm, and a progenitor mass-loss rate of $\dot{M}={10}^{-2}{M}_{\odot }$yr⁻¹. For the assumed progenitor wind velocity ofv_w= 50 km s⁻¹, this corresponds to enhanced mass loss (i.e.,superwindphase) during the last ∼3–6 yr before explosion.