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A sampling-based algorithm for planning smooth nonholonomic paths

The ability to navigate in an environment is essential to the autonomy of mobile robots and unmanned autonomous vehicles. Informally, path planning computes a collision-free path from a start location to a goal location in a known environment. Computing such paths accounting for the kinematics of the robot is a problem widely addressed in the literature, often focusing on feasibility and optimalit

Multiagent connected path planning : pspace-completeness and how to deal with it

In the Multiagent Connected Path Planning problem (MCPP), a team of agents moving in a graph-represented environment must plan a set of start-goal joint paths which ensures global connectivity at each time step, under some communication model. The decision version of this problem asking for the existence of a plan that can be executed in at most a given number of steps is claimed to be NP-complete

Exploiting structure and uncertainty of Bellman updates in Markov decision processes

In many real-world problems stochasticity is a critical issue for the learning process. The sources of stochasticity come from the transition model, the explorative component of the policy or, even worse, from noisy observations of the reward function. For a finite number of samples, traditional Reinforcement Learning (RL) methods provide biased estimates of the action-value function possibly lead

Gradient-based minimization for multi-expert Inverse Reinforcement Learning

We present a model-free method for solving the Inverse Reinforcement Learning (IRL) problem given a set of trajectories generated by different experts' policies. In many applications, the observed demonstrations are not produced by the same policy. In fact, they may be provided by multiple experts that follow different (but similar) policies or even by the same expert that does not always replicat

Distilling contact planning for fast trajectory optimization in Robot Air Hockey

Robot control through contact is challenging as it requires reasoning over long horizons and discontinuous system dynamics. Highly dynamic tasks such as Air Hockey additionally require agile behavior, making the corresponding optimal control problems intractable for planning in realtime. Learning-based approaches address this issue by shifting computationally expensive reasoning through contacts t

A critical look at the EU AI Act’s requirements and affected systems : who must explain what?

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

Late-onset sepsis treatment in very preterm infants alters longitudinal microbiome trajectory with lower abundance of Bifidobacterium despite probiotic supplementation

Introduction: Taxonomic instability within the dynamic gut microbiome of very preterm infants can be associated with various adverse outcomes. This longitudinal study was designed to follow the trajectory of microbiome composition and abundance in a cohort of probiotic supplemented very preterm infants with and without sepsis. Methods: Stool samples (n = 180) from probiotic-supplemented participan

Vacuum impregnation for β-carotene retention in mango prior to solar drying

Vacuum impregnation (Ⅵ) is a versatile processing technique that enhances the nutritional and functional properties of fruits and vegetables by infusing bioactive compounds into their porous structures. This study demonstrates the utility of Ⅵ for fortifying fresh mango with β-carotene, a critical nutrient for addressing vitamin A deficiency, and for mitigating nutrient loss during solar drying. F

NK-A 17E-233I: a novel competitive inhibitor of human dihydroorotate dehydrogenase (DHODH) for cancer therapy

Human dihydroorotate dehydrogenase (DHODH) is the rate-limiting enzyme in pyrimidine de novo synthesis and represents a promising target for cancer therapy. However, current inhibitors of DHODH have limited clinical effectiveness and adverse effects. Herein, we report NK-A 17E-233I, a novel small-molecule inhibitor of the human DHODH enzyme, identified through a prospective virtual screening metho

Fate and transport of perfluoroalkyl acids (PFAAs) in soil and groundwater

PFAAs emission to the environment represents a potential risk to human health. Although, long-term global scale fate and transport models have been used to investigate potential trends in environmental levels, temporal trends and transports mechanisms of PFAAs are not fully understood. Due to high solubility in water, the behaviour of PFAAs in soil is important for environmental fate estimation an

Effects of various organic compounds on growth and phosphorus uptake of an arbuscular mycorrhizal fungus

The influence of three organic compounds and bakers' dry yeast on growth of external mycelium and phosphorus uptake of the arbuscular mycorrhizal fungus Glomus intraradices Schenck and Smith (BEG 87) was examined. Two experiments were carried out in compartmentalized growth systems with root-free sand or soil compartments. The sand and soil in the root-free compartments were left untreated or unif

A global database of soil microbial phospholipid fatty acids and enzyme activities

Soil microbes drive ecosystem function and play a critical role in how ecosystems respond to global change. Research surrounding soil microbial communities has rapidly increased in recent decades, and substantial data relating to phospholipid fatty acids (PLFAs) and potential enzyme activity have been collected and analysed. However, studies have mostly been restricted to local and regional scales

Opposing effects of nitrogen versus phosphorus additions on mycorrhizal fungal abundance along an elevational gradient in tropical montane forests

Studies in temperate systems provide evidence that the abundance of arbuscular mycorrhizal fungal (AMF) depends on soil nutrient availability, which is mainly explained in the context of resource stoichiometry and differential plant biomass allocation. We applied this concept to an understudied ecosystem - tropical montane forest - analyzing root and AMF abundance along an elevational gradient wit

Slash-and-burn practices decrease arbuscular mycorrhizal fungi abundance in soil and the roots of Didierea madagascariensis in the dry tropical forest of madagascar

Deforestation and the use of fire to clear land have drastic effects on ecosystem functioning and compromise essential ecosystem services, especially in low-income tropical countries such as Madagascar. We evaluated the effects of local slash-and-burn practices on soil nutrients and arbuscular mycorrhizal (AM) fungi abundance in a southwestern Madagascar forest. Nine sampling plot pairs were estab

Fine-tuning Myoelectric Control through Reinforcement Learning in a Game Environment

Objective: Enhancing the reliability of myoelectric controllers that decode motor intent is a pressing challenge in the field of bionic prosthetics. State-of-the-art research has mostly focused on Supervised Learning (SL) techniques to tackle this problem. However, obtaining high-quality labeled data that accurately represents muscle activity during daily usage remains difficult. We investigate th

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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

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This paper addresses the time-optimal path-tracking problem for redundant manipulators. By integrating path-velocity control into existing task-space robot controllers, the task-space motion can be dynamically scaled to satisfy the torque constraint under both kinematic and dynamic uncertainties. Numerical simulations and experiments demonstrate that trajectory feasibility and path-tracking accura

Infrastructuring independent cultural production : Empirical and conceptual explorations

Denna avhandling undersöker oberoende kulturproduktion som idé(al) och fenomen, särskilt den centrala roll som samarbeten och ömsesidiga beroenden har för oberoende kulturaktörer. Samtida oberoende kulturproduktion både tillåter och kräver organisering i ett spänningsfält av olika förväntningar och begränsade rumsliga, finansiella och mänskliga resurser. I en tid av allt starkare politisk motvind,This thesis engages with the phenomenon of independent cultural production, which empirically shows itself as an idea(l) of self-determined cultural production and collaboration made possible through numerous different relationships. Independence, as a relational concept, achieved through in(ter)dependencies is what this thesis sets out to explore. Definitions of independence in cultural productio

Phosphorus stress-induced root exudates mediated plant-microbe interactions of Melilotus officinalis

Phosphorus deficiency exacerbates the challenges of phytoremediation in mining areas, particularly for herbaceous species. Although Melilotus officinalis L. Pall. (Melilotus) serves as a pioneer species in mine reclamation, its response mechanisms to phosphorus deficiency stress (PDS)—particularly regarding root exudates composition, plant growth, soil properties, and key microbial functional grou