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An emerging application of wireless sensing is locating and tracking humans in their living environments, a primitive that can be leveraged in both daily life applications and emergency situations. However, most proposed methods have limited spatial resolution when multiple humans are in close vicinity. The problem becomes exacerbated when there is no line-of-sight path to the humans. In this paper, we consider multi-person localization of humans in close vicinity of each other. We propose the use of synthetic aperture radar that combines both translation and rotation to increase effective aperture size, leveraging small rhythmic changes in the radar range due to human breathing. We experimentally evaluate the proposed algorithm in both line-of-sight and through-wall cases with three to five humans in the scene. Our experimental results show that: (i) larger synthetic apertures due to radar translation improve multi-person localization, e.g., by 1.42× when the aperture size is increased by a factor of 2×, and (ii) rotation can largely compensate for gains provided by translation, e.g., rotating the radar over 360° without changing the aperture size results in 1.22× gains over no rotation. Overall, maximal gains of 2.19× are achieved by rotating and translating over a 2× larger aperture. 

Abstract High-pressure electrical resistivity measurements reveal that the mechanical deformation of ultra-hard WB 2 during compression induces superconductivity above 50 GPa with a maximum superconducting critical temperature, T c of 17 K at 91 GPa. Upon further compression up to 187 GPa, the T c gradually decreases. Theoretical calculations show that electron-phonon mediated superconductivity originates from the formation of metastable stacking faults and twin boundaries that exhibit a local structure resembling MgB 2 (hP3, space group 191, prototype AlB 2 ). Synchrotron x-ray diffraction measurements up to 145 GPa show that the ambient pressure hP12 structure (space group 194, prototype WB 2 ) continues to persist to this pressure, consistent with the formation of the planar defects above 50 GPa. The abrupt appearance of superconductivity under pressure does not coincide with a structural transition but instead with the formation and percolation of mechanically-induced stacking faults and twin boundaries. The results identify an alternate route for designing superconducting materials. 

3D printing technology has played an integral part in the growth of makerspaces, showing potential in enabling the integration of art (A) with science, technology, engineering, and math (STEM) disciplines, giving new possibilities to STEAM implementation. This paper presents the effectiveness of a deployable mobile making platform and its curriculum, focused on 3D printing education. This setup, which draws inspiration from modern makerspaces, was deployed for 227 undergraduate students in Art and Engineering majors at multiple campuses of a large northeastern university and used in either a pre-arranged hour-long session or voluntary walk-in session. Self-reported surveys were created to measure participants’ pre- and post-exposure awareness of 3D printing, design, and STEAM quantified through their (1) familiarity, (2) attitude, (3) interest, and (4) self-efficacy. Additionally, observations on participant engagement and use of the space were made. Statistically significant increases in awareness of 3D printing technology were observed in the participants from both Art and Engineering majors, as well as at different campus locations, irrespective of their initial differences. Observations also show a difference in engagement between prearranged sessions and walk-in sessions, which indicates that different session formats may promote specific engagement with different participant types. Ultimately, this research demonstrates two key findings: (1) though they may gravitate to different elements of 3D printing and design, a single makerspace can be used to engage both Art and Engineering students and (2) by introducing mobility to the traditional idea of a makerspace, participants with different initial levels of AM awareness can be brought to similar final awareness. This second finding is especially essential given the disparities in modern student access to 3D printing technology.