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In this work we investigate the development of functionally graded cemented carbides, featuring macro gradients on the millimeter scale, where Fe, or Ni is the binder phase. Two composites, WC-Ni and WC-Fe with 20 % binder by volume were produced by addition of TiC on the surface of the samples before sintering at 1475 °C for 1 h. The sintered samples were analyzed using electron microscopy and mi
An adaptive controller is proposed and analyzed for the class of infinite-horizon optimal control problems in positive linear systems presented in (Ohlin et al., 2024b). This controller is derived from the solution of a “data-driven algebraic equation” constructed using the model-free Bellman equation from Q-learning. The equation is driven by data correlation matrices that do not scale with the n
This paper presents a novel adaptive autotuning strategy for controlling the pH in microalgae raceway reactors, a critical variable in optimizing biomass productivity under dynamic environmental conditions. The method expands on existing relay-based autotuning principles, tailored to suit the seasonally variable dynamics of microalgae cultivation systems influenced by CO2 injection and photosynthe
Finding local features that are repeatable across multiple views is a cornerstone of sparse 3D reconstruction. The classical image matching paradigm detects keypoints per-image once and for all, which can yield poorly-localized features and propagate large errors to the final geometry. In this article, we refine two key steps of structure-from-motion by a direct alignment of low-level image inform
In this chapter, we explore mathematical tools for assessing the stability, convergence, and boundedness of trajectories in generally nonlinear dynamical systems. We delve into the seminal theorems introduced by A. Lyapunov which are primarily concerned with the stability of equilibrium points. The chapter progresses to discuss the extension of Lyapunov's Theory, due to LaSalle, aimed at assessing
The Artificial Intelligence (AI) Act is a relatively new regulation set out in the European Union (EU). It lays out various requirements for AI systems that are placed on the market in the EU. This paper provides a critical and differentiated view of its requirements from a software engineering perspective. A detailed analysis of the legal document shows what requirements are set out for different
This paper presents a decentralized strategy for a team of N robotic manipulators cooperatively grasping and manipulating an object. A two-step strategy has been designed. In the first step, each robot runs N − 1 consensus-based estimators to estimates the wrenches applied to the object by its teammates even when direct all-to-all communication is unavailable. In the second step, each manipulator
Resource provisioning for applications hosted in the cloud is a difficult task due to inherent performance variability in the infrastructure. Control theory has proven to be an efficient tool to increase the predictability of cloud applications. However, a prerequisite for a successful control design is an adequate model of the involved dynamics. In this paper we focus on modeling of controlled se
Realistic representation of atmospheric aerosol size distribution dynamics in large-scale climate models is important for developing accurate descriptions of aerosol-cloud interactions. Despite the dynamic nature of the distributions, which have large seasonal and diurnal changes, model evaluations often focus on the annual median size distribution. Using more comprehensive monthly and diurnal mod
The Hunga Tonga eruption on 15 January 2022 (HT-22) induced vigorous volcano–sea interaction. Here we study the stratospheric aerosol and water vapor resulting from the eruption using satellite-based instruments: the CALIOP lidar and the Microwave Limb Sounder (MLS). We investigate the stratospheric relative humidity following the record-breaking water vapor injections from the HT-22 eruption and
Structure-from-Motion (SfM) has become a ubiquitous tool for camera calibration and scene reconstruction with many downstream applications in computer vision and beyond. While the state-of-the-art SfM pipelines have reached a high level of maturity in well-textured and well-configured scenes over the last decades, they still fall short of robustly solving the SfM problem in challenging scenarios.
Chains of tasks are ubiquitous and used in a broad spectrum of applications. In these chains, tasks execute according to their timing. Then, they communicate by writing to and reading from shared memory. The schedule of tasks and the read/write instants are naturally subject to uncertainties (variability in the execution time, interference due to shared resources of higher priority tasks, etc.). D
Digital control systems introduce unavoidable computational latencies. For some controllers this time delay inhibits practical use, even though they in theory could provide more efficient control. For example, solving an optimization problem each sampling period when using model predictive control. By sampling faster than the computation time and executing independent controllers on distributed ha
This paper presents a method for online estimation of contact properties during in-hand sliding manipulation with a parallel gripper. We estimate the static and Coulomb friction as well as the contact radius from tactile measurements of contact forces and sliding velocities. The method is validated in both simulation and real-world experiments. Furthermore, we propose a heuristic to deal with fast
Modern real-time control systems can sporadically exceed the computation deadlines, which may lead to a deterioration in performance or even instability if not actively accounted for. This letter proposes a stochastic model predictive control approach that incorporates deadline miss probabilities of subsequent control task executions in a scenario tree. To account for the effect of missed deadline
This is the Replicated Computational Results (RCR) Report for the article ‘Stress Testing Control Loops in Cyber-Physical Systems’. The article proposes a novel approach for testing Cyber-Physical Systems (CPS) based on the integration of the guarantees that can be provided with the control theoretical models into the software testing practices. This RCR report describes how to reproduce the empir
Dynamic task offloading is essential for real-time robotic applications, enabling them to adapt to fluctuating computational demands and maintain efficiency under changing conditions. This paper introduces a dynamic task offloading framework that incorporates monitoring, decision making, offloading triggering, and performance monitoring to optimize resource usage by offloading real-time tasks to e
The need for information about climate change is great. This information is usually based on climate model data, which often have systematic biases. Furthermore, climate information is based on ensembles of climate models, which raises the question about how such ensembles are affected by the choice of models and emission scenarios. Here, we aim to describe climate change in Sweden and neighbourin
Rapporten sammanfattar fjärilsinventeringar utförda 2024 inom Biogeografisk uppföljning som drivs av Naturvårdsverket. I fjällområdet inventerades totalt 35 ytor. Sammanlagt noterades 33 högnordiska blåvingar på 11 av 16 inventerade ytor, 36 dvärgpärlemorfjärilar på 12 av 18 ytor och 13 fjällsilversmygare på 4 inventerade ytor. Svartfläckig blåvinge observerades på 26 av 49 inventerade lokaler. To
The radiative properties of clouds depend partially on the cloud droplet number concentration, which is determined by the concentration of cloud condensation nuclei (CCN) when the clouds are formed. In turn, CCN concentrations are determined by the atmospheric particle size distribution and their chemical composition. We use a novel Lagrangian modelling framework to examine the origins and history
