151 research outputs found
Symbol-Level Precoding for Integrated Sensing and Communications: A Faster-Than-Nyquist Approach
In this paper, we propose a novel symbol-level precoding (SLP) method for a
multi-user multi-input multi-output (MU-MIMO) downlink Integrated Sensing and
Communications (ISAC) system based on faster-than-Nyquist (FTN) signaling. Our
method minimizes the minimum mean squared error (MMSE) for target parameter
estimation while guaranteeing per-user quality-of-service by exploiting
constructive interference (CI) techniques. We tackle the non-convex problem
using an efficient successive convex approximation (SCA) method. Numerical
results demonstrate that our FTN-ISAC-SLP design significantly outperforms
conventional benchmarks in both communication and sensing performance
Defining the minimal components of the influenza A virus replication machinery via an in vitro reconstitution system
During influenza A virus infection, the viral RNA polymerase transcribes the viral negative-sense segmented RNA genome and replicates it in a two-step process via complementary RNA within viral ribonucleoprotein (vRNP) complexes. While numerous viral and host factors involved in vRNP functions have been identified, dissecting the roles of individual factors remains challenging due to the complex cellular environment in which vRNP activity has been studied. To overcome this challenge, we reconstituted viral transcription and a full cycle of replication in a test tube using vRNPs isolated from virions and recombinant factors essential for these processes. This novel system uncovers the minimal components required for influenza virus replication and also reveals new roles of regulatory factors in viral replication. Moreover, it sheds light on the molecular interplay underlying the temporal regulation of viral transcription and replication. Our highly robust in vitro system enables systematic functional analysis of factors modulating influenza virus vRNP activity and paves the way for imaging key steps of viral transcription and replication
Anomaly Detection and Prediction Based on Holt-Winters Method
Outliers, detection and prediction of abnormal periods, and prediction of trends in a given time base on existing data are the first problems to be solved in intelligent operation and maintenance. This paper took KPI performance index of 58 cells covered by 5 base stations from August 28 to September 25, 2021 as research data, chose 3 indexes (average number of users, PDCP traffic and average activation number), established a set of outlier prediction system based on Holt-Winters method
Neural Network-PSO-based Velocity Control Algorithm for Landing UAVs on a Boat
Precise landing of Unmanned Aerial Vehicles (UAVs) onto moving platforms like
Autonomous Surface Vehicles (ASVs) is both important and challenging,
especially in GPS-denied environments, for collaborative navigation of
heterogeneous vehicles. UAVs need to land within a confined space onboard ASV
to get energy replenishment, while ASV is subject to translational and
rotational disturbances due to wind and water flow. Current solutions either
rely on high-level waypoint navigation, which struggles to robustly land on
varied-speed targets, or necessitate laborious manual tuning of controller
parameters, and expensive sensors for target localization. Therefore, we
propose an adaptive velocity control algorithm that leverages Particle Swarm
Optimization (PSO) and Neural Network (NN) to optimize PID parameters across
varying flight altitudes and distinct speeds of a moving boat. The cost
function of PSO includes the status change rates of UAV and proximity to the
target. The NN further interpolates the PSO-founded PID parameters. The
proposed method implemented on a water strider hexacopter design, not only
ensures accuracy but also increases robustness. Moreover, this NN-PSO can be
readily adapted to suit various mission requirements. Its ability to achieve
precise landings extends its applicability to scenarios, including but not
limited to rescue missions, package deliveries, and workspace inspections
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