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We derive a nonlinear equation of motion for a chip-scale pendulum comprising a thick plate suspended from a tensioned nanoribbon. Recently, we explored the use of such a device as a clock gravimeter, exploiting the parametric coupling of its frequency to the local acceleration of gravity and demonstrating micro-g resolution with a silicon nitride prototype. Here we consider the restoring torque arising from the mid-plane stretching of the nanoribbon, finding it is a hardening spring that can be used to counteract the softening of gravitational torques, reducing parametric frequency noise and extending the range of isochronous pendulation. Using the method of multiple scales, we predict that parametric frequency-amplitude coupling can be driven to zero by exploiting fabrication tolerances available using modern nanolithography. 

This paper investigates the weaknesses of image watermarking techniques. We present WAVES (Watermark Analysis Via Enhanced Stress-testing), a novel benchmark for assessing watermark robustness, overcoming the limitations of current evaluation methods.WAVES integrates detection and identification tasks, and establishes a standardized evaluation protocol comprised of a diverse range of stress tests. The attacks in WAVES range from traditional image distortions to advanced and novel variations of adversarial, diffusive, and embedding-based attacks. We introduce a normalized score of attack potency which incorporates several widely used image quality metrics and allows us to produce of an ordered ranking of attacks. Our comprehensive evaluation over reveals previously undetected vulnerabilities of several modern watermarking algorithms. WAVES is envisioned as a toolkit for the future development of robust watermarking systems. 

Most engineering ethics education is segregated into particular courses that, from a student’s perspective, can feel disconnected from the technical education at the center of their programs. In part because of this disconnect, several immersive programs designed to train engineering students in socio-technical systems thinking have emerged in the U.S. in the past two decades. One pedagogical goal of these programs is to provide alternative ideologies and practices that counter dominant cultural paradigms that marginalize macroethical thinking and social justice perspectives in engineering schools. In theory, longer-term immersion in such programs can help students overcome these harmful ideologies. However, because of the difficult nature of studying cultural change, very few studies have attempted to provide a thick description of how these alternative cultural practices are influencing student perspectives on engineering practices. Our study offers a rare glimpse at student uptake of these practices in a multi-year Science, Technology, and Society (STS) living-learning program. Our study explores whether and how cultural practices within an STS program help students develop and sustain the resources for using a socio-technical systems thinking approach to engineering practice. We grounded our work in a cultural practices framework from Nasir and Kirshner [1] which roughly understands practice to be “a patterned set of actions performed by members of a group based on common purposes and expectations, with shared cultural values, tools, and meanings” ([2, p. 99] as cited in [3]). Our descriptions of collective enactments of cultural practices are grounded in accounts of classroom events from researcher fieldnotes and reflections in student interviews. Looking across the enactment of practices in classrooms and students’ interpretations of these events in interviews allows us to describe the multiplicity of meanings that students distill from these activities. This paper will present on multiple cultural practices salient to students we have identified in this STS community, for example: cultivating an ethics of care, making the invisible visible, understanding systems from multiple perspectives, and empowering students to develop moral stances as citizens and scientists/engineers in society. Because of the complexity of the interplay between the scaffolding of the STS program’s pedagogy and the emergence of these four themes, we chose to center “cultivating an ethics of care” in this analysis and relationally explore the other three themes through it. Ethics of care manifests in two basic ways in the data. Students talk about how an ethics of care is part of the STS program community and how the STS program fosters the need for an ethics of care toward communities outside the classroom through human-centered engineering design. 

Many studies show that college engineering students’ sense of ethical and social responsibility declines over the course of their college careers (Cech, 2014; Canny & Bielefeldt, 2015; Schiff et al., 2021). One reason is that many college engineering programs and courses reinforce the social-technical dualism, which treats social and macro-ethical issues as distinct from the technical work more often associated with “real” engineering. Some programs, like the Science, Technology and Society (STS) program at [institution made confidential for review], attempt to challenge this dualism by supporting the integration of social and technical considerations within students’ design work and by asking students to grapple with the complex ethics of their work. However, this program is still embedded within a department, university, and society that subscribes to harmful ideologies such as technocracy, capitalism, and meritocracy, which value efficiency, surveillance, and control. These ideologies and their associated values constrain the imagination for what is possible in design work, for instance, by relying on technological ‘quick fixes’ to address complex social problems or by propping up large corporations as innovators, without adequately grappling with the harm that these corporations might be doing. This cultural reality creates an uphill battle for educators attempting to support engineering students’ sense of social consciousness and ethical responsibility. Thus, this study attempts to understand how engineering students’ imaginations are being constrained by societal structures and ideologies and when do they “break free” from these constraints? In this paper, we present a preliminary analysis of first-year STS students collaboratively reasoning through a simulated design scenario about a small community store facing challenges related to the Covid-19 pandemic (adapted from Gupta, 2017). Using discourse and narrative analysis, we analyzed multiple focus group interviews to identify what we call “co-occurrences,” or ideas that tend to hang together in participants’ reasoning. Examining these co-occurrences provides insight into the variety of ways socio-technical imaginaries play out in students’ design thinking.