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We investigate optimal mass transport problem of affine-nonlinear dynamical systems with input and density constraints. Three algorithms are proposed to tackle this problem, including two Uzawa-type methods and a splitting algorithm based on the Douglas-Rachford algorithm. Some preliminary simulation results are presented to demonstrate the effectiveness of our approaches.
This paper investigates the use of decentralised control architectures with heterogeneous dynamics for improving performance in large-scale systems. Our focus is on two well-known decentralised approaches; the 'predecessor following' and 'bidirectional' architectures for vehicle platooning. The former, utilising homogeneous control dynamics, is known to face exponential growth in disturbance ampli
This paper concerns control of a class of systems where multiple dynamically stable agents share a nonlinear and bounded control-interconnection. The agents are subject to a disturbance which is too large to reject with the available control action, making it impossible to stabilize all agents in their desired states. In this nonlinear setting, we consider two different anti-windup equipped propor
This letter presents and analyzes an adaptive data-driven controller that learns the optimal processing rate in a multi-unit processing network in the presence of disturbances. We formulate an optimization problem of linear cost, linear dynamics for the processing network model and an affine constraint on the dispatcher policy. A data-driven linear equation is constructed, based on which the onlin
The scattering formulation of characteristic mode decomposition is utilized to extend modal analysis to lossless scatterers breaking time-reversal symmetry. This enables characteristic modes analysis on devices containing gyrotropic or moving media. The resulting nonreciprocity introduces features not observed in reciprocal scenarios, such as asymmetric phase progression in characteristic far fiel
We present a method for optimal control with respect to a linear cost function for positive linear systems with coupled input constraints. We show that the Bellman equation giving the optimal cost function and resulting sparse state feedback for these systems can be stated explicitly, with the solution given by a linear program. Our framework admits a range of network routing problems with underly
We present an explicit solution to the discrete-time Bellman equation for minimax optimal control of positive systems under unconstrained disturbances. The primary contribution of our result relies on deducing a bound for the disturbance penalty, which characterizes the existence of a finite solution to the problem class. Moreover, this constraint on the disturbance penalty reveals that, in scenar
Background: Studies on risk factors for severe COVID-19 in people of working age have generally not included non-working persons or established population attributable fractions (PAFs) for occupational and other factors. Objectives: We describe the effect of job-related, sociodemographic, and other exposures on the incidence, relative risks and PAFs of severe COVID-19 in individuals aged 18–64. Me
Introduction: Obstetric anal sphincter injuries (OASIS) are severe complications to vaginal births with potentially serious long-term consequences and large impact on quality of life. The aim was to determine risk and protective factors for OASIS. Material and methods: We performed a retrospective register-based observational study. A cohort of 988 988 singleton term deliveries 2005–2016 in Sweden
Background: Exposure to many contacts is the main risk factor for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, while risk of serious disease and death is chiefly determined by old age and comorbidities. Relative and population-attributable fractions (PAFs) of multiple medical and social exposures for COVID-19 outcomes have not been evaluated among older adults. Objective
This letter gives a closed-form expression for an H-infinity optimal controller with diagonal gain matrix. This phenomenon occurs for certain network systems with acyclic graphs, and potential applications include irrigation networks. Moreover, the above is identified as a special case of a particular controller structure which is shown to be H-infinity optimal if the controller and the resulting
In this letter we derive fundamental limitations on the levels of H {2} and H {\infty {}} performance that can be achieved when controlling lossless systems. The results are applied to the swing equation power system model, where it is shown that the fundamental limit on the H {2} norm scales with the inverse of the harmonic mean of the inertias in the system. This indicates that power systems may
Aim: Understanding the spatial ecology of animal movements is a critical element in conserving long-lived, highly mobile marine species. Analyzing networks developed from movements of six sea turtle species reveals marine connectivity and can help prioritize conservation efforts. Location: Global. Methods: We collated telemetry data from 1235 individuals and reviewed the literature to determine ou
The Large Intelligent Surface (LIS) is a promising technology in the areas of wireless communication, remote sensing and positioning. It consists of a continuous radiating surface located in the proximity of the users, with the capability to communicate by transmission and reception (replacing base stations). Despite its potential, there are numerous challenges from an implementation point of view
A wideband power amplifier (PA), with 88% fractional bandwidth operating in the 700 MHz to 1.8 GHz range, which covers most of the standardized narrowband internet-of-things (NB-IoT) and LTE-M bands, is fully integrated in 22 nm CMOS FDSOI. A single-stage differential amplifier core, combined with an on-chip balun, realizes a single-ended output. A stacked circuit architecture, with 3.3 V LDMOS tr
Beyond-5G wireless communication systems will feature advanced, key technologies such as large intelligent surfaces (LISs) composed of a very large number of antenna elements. The concomitant tremendous data rate requirements, due to the communication between these antennas, necessitate careful algorithm-architecture codesign. This paper presents an application-specific integrated circuit (ASIC) a
In this paper we consider calibration of hydraulic models for district heating networks based on operational data. We extend previous theoretical work on the topic to handle real-world complications, namely unknown valve characteristics and hysteresis. We generate two datasets in the Smart Water Infrastructure Laboratory in Aalborg, Denmark, on which we evaluate the proposed procedure. In the firs
We consider control of multiple stable first-order systems which have a control coupling described by an M-matrix. These agents are subject to incremental sector-bounded nonlinearities. We show that such plants can be globally asymptotically stabilized to a unique equilibrium using fully decentralized proportional integral anti-windup-equipped controllers subject to local tuning rules. In addition
