Without a minute to spare

This music score was submitted for Resonate 2024: An Open Access Call for Scores by the UCLA Music Library

A nanofabricated, monolithic, path-separated electron interferometer

We report a self-aligned, monolithic electron interferometer, consisting of two 45 nm thick silicon layers separated by 20 $\mu$m. This interferometer was fabricated from a single crystal silicon cantilever on a transmission electron microscope grid by gallium focused ion-beam milling. Using this interferometer, we demonstrate beam path-separation, and obtain interference fringes in a Mach-Zehnder geometry, in an unmodified 200 kV transmission electron microscope. The fringes have a period of 0.32 nm, which corresponds to the $\left[\bar{1}\bar{1}1\right]$ lattice planes of silicon, and a maximum contrast of 15 %. This design can potentially be scaled to millimeter-scale, and used in electron holography. It can also be applied to perform fundamental physics experiments, such as interaction-free measurement with electrons.Comment: 21 pages (including supplementary info), 8 figures; Corrected typos, added references for introduction and conclusion, changed ordering of paragraphs of Discussion, results unchange

The Development of Prospective Primary School Science Teachers’ TPaCK Fostered by Innovative Science-Teacher Education

The EEdnaS study “Development and testing of digitally enriched science-related subject matter teaching in digital teaching-learning labs and university classrooms” aims to promote the professional competencies of prospective teachers that are needed for teaching science content in a world shaped by digitalization. To achieve this goal, university teaching units (seminars) that directly address cognitive components of a teacher’s professional competencies, which are important to teaching science content in primary school education, were developed. In addition, prospective teachers were asked to plan, implement, and evaluate primary school science education with a particular focus on digitization, as well as sharing the developed units as open-educational resources. This article reports on the impact of the first part of the seminar concept, in which the promotion of digitization-related, subject-specific teaching methodology, as well as content-related knowledge (TPaCK) was systematically promoted. In a standardized survey, it could be shown that the prospective teachers demonstrated positive developments, particularly in the components PCK, TCK, TPK, as well as TPaCK, regarding the self-efficacy in cognitive characteristics about one’s own ability within the reference frame of self. Furthermore, the development of knowledge, especially in the areas of TK, PCK, TCK, and TPK, could also be determined, but not in relation to TPaCK itself

A Stiffness-Adjustable Hyperredundant Manipulator Using a Variable Neutral-Line Mechanism for Minimally Invasive Surgery

In robotic single-port surgery, it is desirable for a manipulator to exhibit the property of variable stiffness. Small-port incisions may require both high flexibility of the manipulator for safety purposes, as well as high structural stiffness for operational precision and high payload capability. This paper presents a new hyperredundant tubular manipulator with a variable neutral-line mechanisms and adjustable stiffness. A unique asymmetric arrangement of the tendons and the links realizes both articulation of the manipulator and continuous stiffness modulation. This asymmetric motion of the manipulator is compensated by a novel actuation mechanism without affecting its structural stiffness. The paper describes the basic mechanics of the variable neutral-line manipulator, and its stiffness characteristics. Simulation and experimental results verify the performance of the proposed mechanism.Samsung Advanced Institute of Technolog

Low-Complexity 5G Slam with CKF-PHD Filter

In 5G mmWave, simultaneous localization and mapping (SLAM) allows devices to exploit map information to improve their position estimate. Even the most basic SLAM filter based on a Rao-Blackwellized particle filter (RBPF) combined with a probability hypothesis density (PHD) map representation exhibits high complexity. This paper proposes a new implementation method for the 5G SLAM using message passing (MP) and the cubature Kalman filter (CKF). We demonstrate that the proposed method significantly reduces the complexity while retaining the SLAM accuracy of the RBPF-PHD approach