Bridges serve as critical lifelines after seismic events, and closures or rerouting due to earthquake damage can significantly impact the communities that they serve. To reduce bridge damage during an earthquake, nickel-titanium (NiTi) shape memory alloy (SMAs) reinforcement have been proposed. The self-centering and energy dissipation capabilities of NiTi SMA can be used to reduce residual displacements and inhibit critical damage states. However, the high cost of NiTi SMAs necessitates their selective placement in the most structurally efficient locations, requiring coupling with conventional low-carbon steel reinforcement. This coupling of dissimilar metals introduces potential long-term durability and performance concerns, particularly in chloride-rich environments from de-icing salts or marine exposure. These concerns are especially relevant to the Seattle region, where the first U.S. bridge utilizing SMA reinforcement was constructed in 2016. This study aims to characterize the corrosion-induced degradation in reinforced concrete infrastructure incorporating coupled NiTi SMA and steel reinforcement. To investigate the effect of the anode-to-cathode ratio, the exposed area of the steel was varied while keeping the exposed area of NiTi SMA constant. For each anode-to-cathode ratio, three cells were prepared: two half-cells with only steel or NiTi specimens and one coupled cell connecting both materials. All specimens were immersed in a simulated pore concrete solution for 18 days, after which 3% wt NaCl was introduced. After another 18 days, this concentration was increased to 10 wt% NaCl. Electrochemical techniques—including linear polarization resistance, cyclic polarization resistance, and zero-resistance ammetry—were used to evaluate the corrosion behavior of the steel specimens. Results indicate that coupling NiTi and mild steel alters the corrosion response of steel and provides insights into the long-term durability of structures reinforced with coupled NiTi and steel reinforcements.

Biological structures by necessity are often optimized for multi-functionality. Northern gannets (Morus bassanus) have developed the ability to plunge-dive into water at speeds of up to 70 mph in pursuit of fish, surviving high impact loads and yet maintaining maneuverability. Their long, slender, and segmented necks are the opposite of current engineered structures anticipated to resist compressive forces. The goal of the study is to emulate impact survivability afforded by this unconventional design by establishing the mathematical and engineering principles behind observed diving bird morphology. We take inspiration from the musculoskeletal system of the gannets’ necks to examine the effects of muscle connectivity and initial shape on wave propagation in segmented structures. Our study goes beyond previous engineering investigations of water impact that are limited to single segmentation and simple connectivity. We create an experimental setup to systematically evaluate energy distribution with a focus on the initial shape and complex muscle connections. Based on open literature, the findings are the first to show how segmented structures can provide passive control of energy propagation to stabilize structures during impact. Understanding these dynamics allows for engineering of novel multifunctional lightweight structures that passively absorb shock or vibration, allowing maneuverability without compromising performance under compression.

Laser interferometry is a common diagnostic used to measure electron density in plasma experiments. Traditionally, laser interferometers have been employed under the assumption that the scene and reference beams must be equal in length. While this practice maximizes the signal to noise ratio, it provides challenges to experiments requiring multiple laser beams in laboratories with space constraints. Allowing beam paths to be unequal in length would permit increased flexibility in optical setups. In pursuit of this flexibility, some researchers have shown that gas tube laser interferometers with unequal path lengths can produce accurate measurements, provided that the difference in path lengths is equal to some integer multiple of double the cavity length of the gas tube laser. These investigations, however, assumed that the spatial periodicity seen in a homodyne Michelson interferometer configuration will remain constant when employing the same path length differences on a heterodyne Mach-Zehnder interferometer configuration, with which actual plasma density measurements were collected. This work aims to close the gap between proofs of concept and experimental implementations by investigating the signal quality of a Mach-Zehnder heterodyne quadrature helium-neon (HeNe) interferometer over a range of path length differences. Experimental methods and results are given for the benchtop investigation of signal quality. Application of the setup is discussed for measuring plasma density in ZaP-HD, an experimental device at the University of Washington used to demonstrate a sheared-flow-stabilized Z-pinch nuclear fusion space thruster concept.

Low-contrast high-speed video from rotating detonation rocket engines makes analyzing the detonation wave dynamics difficult. This paper outlines a method to process raw video frames into a filtered time series of brightness measured around a discretized one-dimensional annulus, enabling a frequency-domain extraction of wave frequency and wave number. For low-contrast videos in which the combustion chamber boundaries are not readily detected, an alternative approach uses a full-video singular value decomposition (SVD) followed by a manual selection of the annular region. In addition, a Riemannian gradient descent algorithm for SVD computation is investigated, offering the potential for faster convergence under specific conditions. The uncertainty of the frequency analysis procedure is quantified by comparing results against known pressure sensor (PCD) data, demonstrating the robustness and reliability of this method across a range of experimental conditions.

As of 2025, the United States has the highest incarceration rate in the world, with its incarcerated population making up 25% of the incarcerated individuals worldwide. Mass incarceration inflicts the most harm on the most vulnerable populations, disproportionately affecting racial and ethnic minorities and creating insurmountable barriers to reintegrating into society. Prison education programs provide opportunities for growth that help prevent recidivism and support rehabilitation efforts, and with the reinstatement of Pell Grants for incarcerated individuals in 2023, there has never been a better time to expand educational opportunities than now. However, little research has been done on prison education programs, with even less research focusing on enhancing and expanding them to address the specific needs of incarcerated individuals, particularly in digital literacy. In a rapidly evolving digital world, it becomes imperative to ensure that incarcerated people, many of whom have had limited experiences with technology due to extended sentences, have the skills to confidently return to a digital society. This project explores how integrating computer science curricula into correctional facilities can increase rehabilitation, reduce recidivism outcomes for incarcerated individuals, and further support other pre-existing educational programs in prisons. To answer this question, we examined legal documents, performed literature reviews, analyzed previous studies on the incarcerated population, and conducted a comprehensive analysis of outcomes from prior prison education programs. Our findings reveal that computer science education for incarcerated people increases self-efficacy rates, post-employment opportunities, and facilitates a smoother transition back into society. Additionally, integrating computer science through enhanced digital infrastructure can address challenges with current educational programs, such as accessibility, course expansion, and classroom segregation. Collectively, this project represents one of the first studies to explore the possibilities for computer education and prisons, offering valuable insights into the potential to improve rehabilitation, reduce recidivism, and address the digital divide.