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Engineering programs have long struggled with balancing curricula that are rigorous enough to prepare graduates to be capable practitioners and educational experiences that are engaging enough to retain undergraduate students. Data show a little more than half of students who start in a program leave after the first or second year, and that many of those students came to dislike engineering or lost interest in the profession. These findings suggest a mismatch between what incoming students think engineering practice is and what message they receive during their first two years of a program. This work will aim to understand how contextualization of what it means to practice engineering can improve the intentions of students, particularly those identifying as underrepresented minorities and women, to persist in a discipline that historically struggles to retain them. With this understanding, changes can be made to undergraduate engineering education to better retain students. In addition, this work will contribute new knowledge about students’ understanding of what it means to practice engineering and how that understanding changes with exposure to different types of contextualization (e.g., historical or technical). It will also contribute new knowledge about how undergraduate students associate engineering science and judgement with engineering practice, particularly with respect to how these facets of engineering practice are directly in service to design. Engineering science courses that occupy the middle two years of a program most often utilize traditional lecture-based pedagogy and simplified close-ended textbook problems, which do not typically allow students to engage in the kind of decision-making that is essential to developing engineering judgement. This work proposes a teaching pedagogy intended to provide students with context for how engineering science concepts are implemented in authentic engineering practice and how engineering judgement is essential in that implementation. Moreover, this work will aim to employ another teaching pedagogy to provide a more holistic contextualization of engineering practice by introducing students to the history of the profession. This pedagogy was implemented during the Fall 2023 semester in a required seminar course for mechanical engineering sophomores at [name of university]. This work will advance the field of engineering education research by studying how students’ perceptions of engineering practice develop as they progress through a program, and how these educational activities can shape that progress and/or reframe their beliefs about their education and training. Semi-structured interviews will reveal how students’ perceptions of engineering practice change longitudinally and whether the aforementioned educational activities influence that trajectory. In addition, a larger group of students will be invited to participate in surveys, which will enable drawing inferences from a broader sample about intention to persist as well as baseline levels of familiarity with engineering in general. 

While proving, and more broadly conceived “reasoning and sense-making,” have received a great deal of attention in mathematics education research over the past three decades, recently scholars have argued for the importance of justification as a learning and teaching practice. As teachers work toward realizing goals for more equitable classroom environments, little is known about whether teachers’ conceptions about mathematical practices, such as justification, reflect an understanding of how students’ engagement in those practices can support more than just mathematical achievement. In this paper, we present findings from our analysis of interviews with 10 secondary mathematics teachers engaged in participatory action research to explore connections, and potential disconnections, between teachers’ conceptions of justification and their visions for equitable instruction. 

SAGE3 is software to augment the cyberinfrastructure-enhanced research and education enterprise by supporting data-intensive collaboration across a wide range of display devices from high-resolution display walls to laptops. This paper provides insight into SAGE3’s implementation, which significantly improves on prior generations of SAGE by leveraging emerging advancements in Web technologies and Artificial Intelligence. We also provide an overview of new usage patterns that we observed with SAGE3. 

SAGE3 is software to augment the cyberinfrastructure-enhanced research and education enterprise by supporting data-intensive collaboration across a wide range of display devices from high-resolution display walls to laptops. This paper provides insight into SAGE3’s implementation, which significantly improves on prior generations of SAGE by leveraging emerging advancements in Web technologies and Artificial Intelligence. We also provide an overview of new usage patterns that we observed with SAGE3. 

SAGE3 is software to augment the cyberinfrastructure-enhanced research and education enterprise by supporting data-intensive collaboration across a wide range of display devices from high-resolution display walls to laptops. This paper provides insight into SAGE3’s implementation, which significantly improves on prior generations of SAGE by leveraging emerging advancements in Web technologies and Artificial Intelligence. We also provide an overview of new usage patterns that we observed with SAGE3. 

Integrated phononics plays an important role in both fundamental physics and technology. Despite great efforts, it remains a challenge to break time-reversal symmetry to achieve topological phases and non-reciprocal devices. Piezomagnetic materials offer an intriguing opportunity as they break time-reversal symmetry intrinsically, without the need for an external magnetic field or an active driving field. Moreover, they are antiferromagnetic, and possibly compatible with superconducting components. Here, we develop a theoretical framework that combines linear elasticity with Maxwell’s equations via piezoelectricity and/or piezomagnetism beyond the commonly adopted quasi-static approximation. Our theory predicts and numerically demonstrates phononic Chern insulators based on piezomagnetism. We further show that the topological phase and chiral edge states in this system can be controlled by the charge doping. Our results exploit a general duality relation between piezoelectric and piezomagnetic systems, which can potentially be generalized to other composite metamaterial systems.

 

Nanomechanical resonators are built into phones, as filters or accelerometers, but they lack a knob to effectively tune the frequency at the nanoscale when it’s easy to tune on an octave the tone of a classical musical instrument like a guitar string. Moreover, the control of deformation in nanomaterials, as two-dimensional (2D) materials, to tailor their electronic properties, i.e., straintronic, opens up avenues for applications in force detection, bolometry or quantum emitters. An accurate control of the deformation within these materials is thus necessary to fully exploit their potential. The precise study of deformations in 2D materials involves measurements of vibration modes and nanomechanics. By using a suspended MoS₂membrane heated by the Joule effect, we induce a strong softening of the mechanical resonance frequency as a function of the electrothermal heating, over one octave. A simple electrical tension is used to modulate the thermal mechanical tuning. Its amplitude is very large, greater than 100% modulation for one volt, compared to other approaches on 2D or 1D materials and, moreover, a very wide frequency range is accessible. Finally, we have related a photo-induced softening of the membrane over very long times with the current measurements and a photothermal effect.

 

Charge transport in ferroelectric (FE) gated graphene far from the Dirac point (DP) was studied in the temperature range 300 K < T < 350 K. A non-monotonic/monotonic/non-monotonic behavior in the conductivity [σ(T)] was observed as one moved away from the DP. As the gate polarization increased, additional impurity charges were compensated, which reduced charge scattering. The uncompensated charges doped graphene and σ(T) switched to a monotonic increase with increasing T. However, far from the DP, the polarization reached saturation, which resulted in still lower impurity charge scattering. The carrier concentration increased, and a non-monotonic response in σ(T) reappeared, which was attributed to phonon scattering. A theoretical model is presented that combined impurity charge and phonon scattering conduction mechanisms. The top gate polarizable FE provided a novel approach to investigate charge transport in graphene via controlled compensation of impurity charges, and in the process revealed non-monotonic behavior in σ(T) not previously seen in SiO 2 back gated graphene devices. 

Infrequent, large‐magnitude discharge (>10⁶ m³/s) outburst floods—megafloods—can play a major role in landscape evolution. Prehistoric glacial lake outburst megafloods transported and deposited large boulders (≥4 m), yet few studies consider their potential lasting impact on river processes and form. We use a numerical model, constrained by observed boulder size distributions, to investigate the fluvial response to boulder deposition by megaflooding in the Yarlung‐Siang River, eastern Himalaya. Results show that boulder deposition changes local channel steepness (k_sn) up to ∼180% compared to simulations without boulder bars, introducing >100 meter‐scale knickpoints to the channel that can be sustained for >20 kyr. Simulations demonstrate that deposition of boulders in a single megaflood can have a greater influence onk_snthan another common source of fluvial boulders: incision‐rate‐dependent delivery of boulders from hillslopes. Through widespread boulder deposition, megafloods leave a lasting legacy of channel disequilibrium that compounds over multiple floods and persists for millennia.