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Din sökning på "kognition" gav 1618 sökträffar

A Comprehensive Robustness Analysis of Storj DCS Under Coordinated DDoS Attack

Decentralized Cloud Storage (DCS) is considered to be the future for sustainable data storage within Web 3.0, in which we will move from a single cloud service provider to creating an ecosystem where anybody could be a cloud storage provider. Currently, the cloud storage market is highly dominated by centralized players like Amazon S3, Google Cloud, Box, etc. Decentralized projects like Storj, Fil

Language exposure and use in study abroad versus migration contexts: Modelling activity and learner profiles with ESM data

Language exposure and use (LEU) are widely viewed as key factors in multilingual development, and research highlights the importance of considering not just the frequency and quantity of LEU, but also contextual factors such as when and where a language is used, with whom and why. In this study, we illustrate the complexity of LEU in two contexts (study abroad and migration) by applying sequential

Optimal control of linear cost networks

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

Duality-based Dynamical Optimal Transport of Discrete Time Systems

We study dynamical optimal transport of discrete time systems (dDOT) with Lagrangian cost. The problem is approached by combining optimal control and Kantorovich duality theory. Based on the derived solution, a first order splitting algorithm is proposed for numerical implementation. While solving partial differential equations is often required in the continuous time case, a salient feature of ou

Optimal Mass Transport of Nonlinear Systems under Input and Density Constraints

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.

Verification of Low-Dimensional Neural Network Control

We verify safety of a nonlinear continuous-time system controlled by a neural network controller. The system is decomposed into low-dimensional subsystems connected in a feedback loop. Our application is a rocket landing, and open-loop properties of the two-dimensional altitude subsystem are verified using worst-case simulations. Closed-loop safety properties (crash-avoidance) of the full system a

A data-based comparison of methods for reducing the peak flow rate in a district heating system

This work concerns reduction of the peak flow rate of a district heating grid,a key system property which is bounded by pipe dimensions and pumpingcapacity. The peak flow rate constrains the number of additional consumersthat can be connected, and may be a limiting factor in reducing supplytemperatures when transitioning to the 4th generation of district heating.We evaluate a full year of operatio

Conflict simulation for shared autonomy in autonomous driving

We present a tool for modeling conflict situations that enables simulation and testing of situation awareness in shared autonomy, in this case in an autonomous driving scenario. The flexibility of the tool allows definition of new conflict situations, integration with various control and conflict detection systems, as well as customization of Takeover Request (TOR) signals and different means of c

Hydraulic Parameter Estimation for District Heating Based on Laboratory Experiments

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

Decentralized PI-control and Anti-windup in Resource Sharing Networks

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

Using Knowledge Representation and Task Planning for Robot-agnostic Skills on the Example of Contact-Rich Wiping Tasks

The transition to agile manufacturing, Industry 4.0, and high-mix-low-volume tasks require robot programming solutions that are flexible. However, most deployed robot solutions are still statically programmed and use stiff position control, which limit their usefulness. In this paper, we show how a single robot skill that utilizes knowledge representation, task planning, and automatic selection of

Hilbert Metric for Nonlinear Consensus with Varying Topology

New results on continuous time nonlinear consensus under varying topology are presented. The results are proved utilizing non Lyapunov based methods, i.e., the Hilbert metric, showing the possibility of further investigation of Hilbert metric for consensus and synchronization problems.

On the H2 optimal control of uniformly damped mass-spring networks

In this paper we provide an analytical solution to an H2 optimal control problem, that applies whenever the process corresponds to a uniformly damped network of masses and springs. The solution covers both stable and unstable systems, and illustrates analytically how damping affects the levels of achievable performance. Furthermore, the resulting optimal controllers can be synthesised using passiv

Minimax Linear Optimal Control of Positive Systems

We present a novel class of minimax optimal control problems with positive dynamics, linear objective function and homogeneous constraints. The proposed problem class can be analyzed with dynamic programming and an explicit solution to the Bellman equation can be obtained, revealing that the optimal control policy (among all possible policies) is linear. This policy can in turn be computed through

Scheduling for Industrial Control Traffic Using Massive MIMO and Large Intelligent Surfaces

Industry 4.0, with its focus on flexibility and customizability, is pushing in the direction of wireless communication in future smart factories, in particular massive multiple-input multiple-output (MIMO), and its future evolution Large Intelligent Surfaces (LIS), which provide more reliable channel quality than previous technologies. As such, there arises the need to perform efficient scheduling

Learning to Adapt the Parameters of Behavior Trees and Motion Generators (BTMGs) to Task Variations

The ability to learn new tasks and quickly adapt to different variations or dimensions is an important attribute in agile robotics. In our previous work, we have explored Behavior Trees and Motion Generators (BTMGs) as a robot arm policy representation to facilitate the learning and execution of assembly tasks. The current implementation of the BTMGs for a specific task may not be robust to the ch

Uncertainty quantification metrics for deep regression

When deploying deep neural networks on robots or other physical systems, the learned model should reliably quantify predictive uncertainty. A reliable uncertainty allows downstream modules to reason about the safety of its actions. In this work, we address metrics for uncertainty quantification. Specifically, we focus on regression tasks, and investigate Area Under Sparsification Error (AUSE), Cal

A Cone-preserving Solution to a Nonsymmetric Riccati Equation

In this paper, we provide the following simple equivalent condition for a nonsymmetric Algebraic Riccati Equation to admit a stabilizing cone-preserving solution: an associated coefficient matrix must be stable. The result holds under the assumption that said matrix be cross-positive on a proper cone, and it both extends and completes a corresponding sufficient condition for nonnegative matrices i

Throat related symptoms and voice : development of an instrument for self assessment of throat-problems

BACKGROUND: Symptoms from throat (sensation of globus; frequent throat clearing; irritated throat) are common in patients referred to voice clinics and to ENT specialists. The relation to symptoms of voice discomfort is unclear and in some cases patients do not have voice problems at all. Instruments for patients' self-reporting of symptoms, and assessment of handicap, such as the Voice Handicap I