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Novel Data-Driven Discrete Neurodynamics Schemes for Redundant Manipulator Control
No full textIt is very challenging to precisely control a redundant manipulator with an unknown model during the end-effector tracking task. A data-driven approach offers a promising solution for manipulator control under such conditions. In this article, two data-driven discrete neurodynamics (DDDN) schemes are proposed for redundant manipulator tracking control. First, utilizing discrete neurodynamics (DN) principles, the DDDN-1 scheme with an adaptive Jacobian matrix is developed. Subsequently, the DDDN-2 scheme is further presented, which eliminates the need for the Jacobian matrix inversion operation. Detailed theoretical analyses verify the effectiveness of DDDN-1 and DDDN-2 schemes. Additionally, detailed comparisons with existing schemes have been provided. Finally, simulative and physical experiments conducted using the UR5 manipulator validate the theoretical analyses, demonstrating the effectiveness and superiority of DDDN-1 and DDDN-2 schemes.</p
The European bioeconomy strategy revision:An opportunity to go against the tide and secure a sustainable future
No full textIn today's tense geopolitical landscape, marked by strained relations among major powers and deep-rooted dependence on fossil-based economies, the emerging modern bioeconomy can provide resource independence and resilience, in tandem with economic, social, and environmental benefits, and thus has the potential to underpin a sustainable future. The bioeconomy is a vital cross-cutting meta-sector, but it is not inherently circular or sustainable; without intentional design, it risks becoming a linear, unsustainable replacement of the fossil-based economy. Realising its full promise requires purposeful engineering to address climate change, biodiversity loss, strengthen resource independence, support food security and resilience, create jobs, promote social inclusion, boost competitiveness and autonomy, and improve human, animal, and environmental health. The potential is enormous, but so are the challenges society faces in realising the vision for a biobased, nature-positive future.</p
Solvent-Free Hydrogenation and Dehydrogenation of Quinoline and Quinaldine for the LOHC Concept
No full textAs presented herein, N-heterocyclic quinoline (Q) and quinaldine (MeQ) represent promising liquid organic hydrogen carriers (LOHCs). They can be quantitatively hydrogenated to tetrahydro (TH) forms under mild reaction conditions (100 °C and 10 bar of H2) using Pt/C and Pd/C catalysts. It is noteworthy that the hydrogenation occurs without a solvent, yielding hydrogen storage capacities of up to 2.9 wt·%. Further hydrogenation of Q and MeQ to their decahydro (DH) forms requires the presence of a solvent. In addition to the hydrogenation of Q and MeQ, we succeeded in the dehydrogenation of the TH forms under solvent-free reaction conditions. This suggests that a pressure-controlled system with a single catalyst for hydrogenation and dehydrogenation of the MeQ/Q system could enable hydrogen storage under solvent-free reaction conditions. We also examined various substituted pyridine structures to comprehend the role of protective alkyl groups in hydrogenation. However, solvent-free quinaldine hydrogenation reactions are sensitive to steric changes surrounding pyridine nitrogen. Among the structural variations studied, MeQ with one methyl group has proven to be the most favorable
Enhancing Analytical Performance in Cyclic Voltammetry:An Open-Source Tool for Signal Deconvolution
No full textCyclic voltammetry (CV) is a cornerstone of electrochemical analysis, yet the accurate determination of Faradaic peak heights is often compromised by overlapping signals and complex background currents. Traditional analysis relying on linear baseline subtraction is highly inaccurate, particularly for systems with multiple redox processes or interfering species. This work introduces a powerful and accessible automated fitting algorithm that uses semiderivative analysis to deconvolve complex voltammograms, suitable for linear diffusion controlled experiments conducted with planar working electrodes. The method employs flexible Pearson IV distributions to model a wide range of Faradaic peak shapes and introduces a novel piecewise function to accurately fit and subtract both capacitive and background electrolysis currents. The algorithm’s efficacy is demonstrated on three challenging experimental systems: the reversible redox probe [Ru(NH3)6]Cl3 in the presence of interfering oxygen reduction, the sequential ligand reductions of [Ru(bpy)3](PF6)2 featuring heavily overlapping peaks, and the quantitative analysis of SO2 obscured by a large oxygen reduction signal. The results show a dramatic improvement in accuracy and signal deconvolution over the conventional methods. To promote broad adoption, a user-friendly program and its Python source code have been made freely available to the electrochemistry community.</p
MITE: the Minimum Information about a Tailoring Enzyme database for capturing specialized metabolite biosynthesis
No full textSecondary or specialized metabolites show extraordinary structural diversity and potent biological activities relevant for clinical and industrial applications. The biosynthesis of these metabolites usually starts with the assembly of a core ‘scaffold’, which is subsequently modified by tailoring enzymes to define the molecule’s final structure and, in turn, its biological activity profile. Knowledge about reaction and substrate specificity of tailoring enzymes is essential for understanding and computationally predicting metabolite biosynthesis, but this information is usually scattered in the literature. Here, we present MITE, the Minimum Information about a Tailoring Enzyme database. MITE employs a comprehensive set of parameters to annotate tailoring enzymes, defining substrate and reaction specificity by the expressive reaction SMARTS (Simplified Molecular Input Line Entry System Arbitrary Target Specification) chemical pattern language. Both human and machine readable, MITE can be used as a knowledge base, for in silico biosynthesis, or to train machine-learning applications, and tightly integrates with existing resources. Designed as a community-driven and open resource, MITE employs a rolling release model of data curation and expert review. MITE is freely accessible at https://mite.bioinformatics.nl/
Implication of building renovation and renewable integration on the energy resilience in the Nordic climate: Techno-economic analysis using questionnaire-based thresholds
Full text linkAs climate change worsens energy insecurity, resilience to long-term blackouts in cold climates is increasingly critical. Blackouts can compromise indoor heating, leading to serious habitability, health, and survivability risks. Yet, most existing regulatory frameworks lack clear definitions of minimum habitability and survivability thresholds, and often under examine the role of demographic and social factors. This study presents a novel, integrated, human-centric method that combines a single-stage occupants survey—designed to assess energy resilience awareness, occupant-defined habitability and survivability thresholds, and key demographic factors—with a detailed building performance simulation model. Survey data was collected from 378 participants residing in a cold climate region (Finland) and is integrated with simulations of both old and renovated residential buildings, incorporating various passive and active energy systems, including building envelope, photovoltaics (PV), battery storage, and heat pumps. This interdisciplinary approach enables a comprehensive techno-economic analysis that effectively bridges social perceptions with technical assessments of energy resilience. Moreover, a new set of energy resilience indicators is proposed, specifically tailored for buildings in cold regions. These indicators form the basis of a color-based classification scheme used to visualize simulation outcomes and compare the resilience performances of the buildings. Survey results show that heating (i.e., habitability) is the top need in Finland, followed by electrical loads (i.e., survivability). Habitability thresholds differ by age, gender, location, and building type, ranging from 15 °C to 19 °C. Older buildings fail to meet these needs, especially for people over 50 years old. In passive conditions, dissatisfaction among older adults reaches 100 % and elevated psychological stress values. Renovations and renewable energy systems greatly improve resilience, reducing low heating risks and physiological stress—though at a 94 % cost increase. Dissatisfaction with habitability drops from 100 % to 1 %, and survivability improves from 0 % to 98 %. For adults aged 41–61+, dissatisfaction drops to 90 % (men) and 98 % (women) with building renovation, and with PV-battery systems, it falls to 0 % for both. This research offers a transferable, occupant-centered framework for assessing energy resilience, bridging technical, social, and economic dimensions to guide building adaptation in other cold climates and Nordic countries
Gaseous ozone treatment of wood:Effect of treatment conditions on the wood wettability and phenol-formaldehyde adhesive bonding strength
Full text linkFindings of an earlier study, “Improving Wood Surface Wettability through Gas-phase Ozone Treatment of Air-dry Wood,” demonstrated that the wood gas-phase ozone treatment enhances the wettability of wood by water, and thus potentially also the spread, absorption, and adhesion of water-based adhesives and coatings to the wood surfaces. This study extends that work by examining the effect of ozone treatment temperature and the wood moisture content on the wettability of ozone treated wood and bonding strength of phenol-formaldehyde (PF) adhesive. In the present study, both air-dry and wetted birch plywood and veneer were ozone-treated at 23 °C, 35 °C, and 55 °C for 10 and 30 minutes. The amount of reacted ozone increased with higher treatment temperature and with an increase in the wood moisture content. However, the reduction in the water contact angle was more pronounced for air-dry wood. Bonding tests showed that the ozone treatments substantially increased the PF adhesive bonding strength, and the bonding strength correlated negatively with the ozone-treated birch veneer water contact angle. The results suggest that both the treatment temperature and moisture content of the wood during the treatment influenced the ozone reactions with wood, and thus on wood wettability and PF adhesive bonding strength (192 / max. 200).<br/
A nodalization study on modeling the containment and reactor pool of an integral PWR
Full text linkThis study investigates the impact of nodalization of the containment and reactor pool of a small integral Pressurized Water Reactor (iPWR) using the MELCOR 2.2 code. The research focuses on Design 1 of the EU-funded SASPAM-SA project, featuring a containment partially submerged in the reactor pool. Two accident scenarios were analyzed: a Design Basis Accident (DBA) and a severe accident. The simulations were conducted with four different nodalizations: a detailed base model, a single-volume containment model, a single-volume pool model, and a single-volume model for both the containment and the pool. The results indicate that while detailed nodalization can simulate temperature stratification, its effect on the overall accident simulation results, pressures and fission product releases is limited. The findings suggest that differences between single-volume and more detailed nodalizations are relatively small, with the detailed nodalization providing slightly lower containment pressures during the DBA scenario due to more efficient heat transfer