Monocular 3D Human Pose Estimation for Sports Broadcasts using Partial Sports Field Registration

The filming of sporting events projects and flattens the movement of athletes in the world onto a 2D broadcast image. The pixel locations of joints in these images can be detected with high validity. Recovering the actual 3D movement of the limbs (kinematics) of the athletes requires lifting these 2D pixel locations back into a third dimension, implying a certain scene geometry. The well-known line markings of sports fields allow for the calibration of the camera and for determining the actual geometry of the scene. Close-up shots of athletes are required to extract detailed kinematics, which in turn obfuscates the pertinent field markers for camera calibration. We suggest partial sports field registration, which determines a set of scene-consistent camera calibrations up to a single degree of freedom. Through joint optimization of 3D pose estimation and camera calibration, we demonstrate the successful extraction of 3D running kinematics on a 400m track. In this work, we combine advances in 2D human pose estimation and camera calibration via partial sports field registration to demonstrate an avenue for collecting valid large-scale kinematic datasets. We generate a synthetic dataset of more than 10k images in Unreal Engine 5 with different viewpoints, running styles, and body types, to show the limitations of existing monocular 3D HPE methods. Synthetic data and code are available at https://github.com/tobibaum/PartialSportsFieldReg_3DHPE.Comment: accept at "9th International Workshop on Computer Vision in Sports (CVsports) at CVPR 2023

Self-synchronized duty-cycling for sensor networks with energy harvesting capabilities: Implementation in Wiselib

In this work we present a protocol for a self- synchronized duty-cycling mechanism in wireless sensor net- works with energy harvesting capabilities. The protocol is im- plemented in Wiselib, a library of generic algorithms for sensor networks. Simulations are conducted with the sensor network simulator Shawn. They are based on the specifications of real hardware known as iSense sensor nodes. The experimental results show that the proposed mechanism is able to adapt to changing energy availabilities. Moreover, it is shown that the system is very robust against packet loss.Postprint (published version

Terahertz electrical writing speed in an antiferromagnetic memory

The speed of writing of state-of-the-art ferromagnetic memories is physically limited by an intrinsic gigahertz threshold. Recently, realization of memory devices based on antiferromagnets, in which spin directions periodically alternate from one atomic lattice site to the next has moved research in an alternative direction. We experimentally demonstrate at room temperature that the speed of reversible electrical writing in a memory device can be scaled up to terahertz using an antiferromagnet. A current-induced spin-torque mechanism is responsible for the switching in our memory devices throughout the 12-order-of-magnitude range of writing speeds from hertz to terahertz. Our work opens the path toward the development of memory-logic technology reaching the elusive terahertz band

Indikatoren zur Bewertung zukünftiger urbaner Mobilitätsszenarien

Mobilität ist ein zentraler Faktor moderner Gesellschaften, mit sowohl wirtschaftlicher als auch sozialer Relevanz. In ihrer jetzigen Form verursacht Mobilität jedoch eine Reihe negativer Auswirkungen für Mensch und Umwelt, die von der Emission von Treibhausgasen, Luftschadstoffen und Lärmbelastung bis hin zu Flächenverbrauch und hohem Ressourcenverbrauch reichen. Vor diesem Hintergrund besteht weitgehend Einigkeit darüber, dass die heutigen Verkehrs- und Mobilitätssysteme transformiert und nachhaltiger gestaltet werden müssen. Mobilitätsindikatoren haben sich in diesem Rahmen als nützliches Instrument zur Unterstützung der Politikgestaltung und -bewertung erwiesen. In der vorliegenden Arbeit wird das Indikatorensystem aus dem SuMo-Rhine Projekt zur Nachhaltigkeitsbewertung gegenwärtiger und zukünftiger urbaner Mobilitätskonzepte am Fallbeispiel der Karlsruher Oststadt angewendet. Anhand des Beispiels wird gezeigt, wie sensitiv die Bewertungsindikatoren in verschiedenen Zukunftszszenarien auf Veränderungen im Mobilitätssystem reagieren. In Hinblick auf die gewählten Anpassungen im Mobilitätssystem des definierten Untersuchungsraums, können somit Änderungen in den Nachhaltigkeitsperformances der Indikatoren erfasst und bewertet werden

Cherenkov Diffraction Radiation Emissions from Single Electrons and Positrons on a Fused Silica Radiator

Beam diagnostics are crucial for smooth accelerator operations. Many techniques rely on instrumentation in which the beam properties are significantly affected by the measurement. Novel approaches aim to use Cherenkov Diffraction Radiation (ChDR) for non-invasive diagnostics. Unlike regular Cherenkov Radiation, the charged particles do not have to move inside of the medium, but it is sufficient for them to move in its vicinity as long as they are faster than the speed of light in the medium. Changes to the beam properties due to ChDR measurements are consequently negligible. To examine ChDR emission under different conditions, we placed a fused silica radiator in the DESY II Test Beam. We observed a linear increase in ChDR intensity for electron and positron momenta between 1 GeV/c and 5 GeV/c. Additionally, we found that electrons produce significantly more ChDR than positrons for increasing particle momenta. The results suggest a need for further research into the ChDR generation by electrons and positrons and may find application in the design of future beam diagnostic devices

Prediction of in-hospital bleeding in acutely ill medical patients: External validation of the IMPROVE bleeding risk score.

INTRODUCTION Pharmacological thromboprophylaxis slightly increases bleeding risk. The only risk assessment model to predict bleeding in medical inpatients, the IMPROVE bleeding risk score, has never been validated using prospectively collected outcome data. METHODS We validated the IMPROVE bleeding risk score in a prospective multicenter cohort of medical inpatients. Primary outcome was in-hospital clinically relevant bleeding (CRB) within 14 days of admission, a secondary outcome was major bleeding (MB). We classified patients according to the score in high or low bleeding risk. We assessed the score's predictive performance by calculating subhazard ratios (sHRs) adjusted for thromboprophylaxis use, positive and negative predictive values (PPV, NPV), and the area under the receiver operating characteristic curves (AUC). RESULTS Of 1155 patients, 8 % were classified as high bleeding risk. CRB and MB within 14 days occurred in 0.94 % and 0.47 % of low-risk and in 5.6 % and 3.4 % of high-risk patients, respectively. Adjusted for thromboprophylaxis, classification in the high-risk group was associated with an increased risk of 14-day CRB (sHR 4.7, 95 % confidence interval [CI] 1.5-14.5) and MB (sHR 4.9, 95%CI 1.0-23.4). PPV was 5.6 % and 3.4 %, while NPV was 99.1 % and 99.5 % for CRB and MB, respectively. The AUC was 0.68 (95%CI 0.66-0.71) for CRB and 0.73 (95%CI 0.71-0.76) for MB. CONCLUSION The IMPROVE bleeding risk score showed moderate to good discriminatory power to predict bleeding in medical inpatients. The score may help identify patients at high risk of in-hospital bleeding, in whom careful assessment of the risk-benefit ratio of pharmacological thromboprophylaxis is warranted

Autonomous Navigation of a Robotic Swarm in Space Exploration Missions

In recent years the paradigm of navigation has shifted from pinpointing the location of a single agent to continuously estimating the full kinematic state of a team of autonomous agents. In this paper, we propose a kinematic-aware information seeking algorithm for a robotic swarm. The algorithm tightly couples state estimation and autonomous control given ranging and kinematic models. With the help of the Fisher information theory, agents generate information seeking command sequence on their actuators, which leads to smooth trajectories. As an outcome, the swarm continuously optimizes its formation so that the agents’ position and orientation uncertainty is actively minimized. The proposed algorithm is verified by physics simulations and demonstrated in a space-analog mission of autonomous swarm navigation on volcano Mount Etna