Robust optimization for integrated production and energy scheduling in low-carbon factories with captive power plants under decision-dependent uncertainty

Publisher Copyright: © 2024 Elsevier LtdLow-carbon factories with captive power plants represent a new industrial microgrid paradigm of energy conservation and emission reduction in many countries. However, one of the most common challenges of low-carbon management is the joint regulation of factory production and power plant operations under uncertainty. To meet this challenge, a robust optimization-based integrated production and energy (IPE) scheduling approach is proposed in this paper. Firstly, a two-stage adaptive robust optimization model is established to cover all possible realizations of decision-independent uncertainties (e.g. market demands and output power of renewable sources) and decision-dependent uncertainties (e.g. carbon emission densities depending on the choice of production lines). Secondly, a novel parametric column-and-constraint generation algorithm is utilized to derive robust scheduling schemes. The non-trivial scenarios of decision-dependent uncertainties identified in the subproblem are parametrically characterized based on Karush–Kuhn–Tucker conditions, which can be included in the master problem. Finally, simulations on different cases are conducted to test the rationality and validity of the proposed approach. Compared with the separate scheduling of production and energy, IPE scheduling may increase production and energy costs to ensure the robustness of the resulting schemes. Moreover, the proposed approach can mitigate the impacts of uncertainties on IPE scheduling without significantly increasing the computational complexity.Peer reviewe

Unleashing novel configurations of gravitational water vortex thermal energy exchanger

Publisher Copyright: © 2024 Elsevier LtdThis study presents thermal and hydrodynamics investigations for novel configurations of gravitational water vortex heat exchanger (GWVHE). The proposed novel configurations of GWVHE include SWB (shell with baffles), CSFH (circular spiral flow helix) and RSFC (rectangular spiral flow channel). The thermal energy balance between two fluid domains has been calculated numerically for various operational conditions. An analytical model is developed using the Kern's approach, the effectiveness-NTU method, and the LMTD method for heat exchangers to calculate the heat transfer characteristics of two fluids to validate numerical results. Moreover, a transient two-phase flow numerical model has been solved to investigate the volume fraction of air and water during the development of the vortex at the center of the basin. The results show that a convincing thermal energy balance is present between both fluid streams for all the proposed configurations of GWVHE. However, the heat exchange rate for the RSFC configuration of GWVHE is higher than the SWB and CSFH of GWVHE. Because it has maximum heat exchange surface area of 1.08 m2 and thermal losses in RSFC are significantly lower than those computed in CSFH and SWB at different operating conditions. The thermal losses reported for RSFC are just 1 % compared to CSFH and SWB thermal losses of 2 % and 5 %, respectively. Moreover, the maximum volume fraction of air obtained at the center of basin during vortex formation is 18 %, indicating an effective vortex air core.Peer reviewe

Data-driven surface reconstruction for assessing welding-induced distortions in ship-deck panels

Publisher Copyright: Copyright © 2025. Published by Elsevier Ltd.Increasingly stringent regulations on greenhouse gas emissions have sparked interest in lightweight, thin-walled deck panels for cruise ship superstructures. Throughout the ship assembly, irregular welding-induced distortions accumulate on thin plates, affecting their load-carrying capacity significantly. Due to complex geometries, the assessment of distorted thin-walled panel units relies on accurate finite element modeling based on high-density optical scanning measurements, provided as unorganized point clouds (PC). This poses challenges in terms of processing of the data for surface reconstruction and data storage. This paper presents a computationally efficient, iterative B-spline surface fitting procedure for surface reconstruction from an unorganized 3D PC for the finite element analysis of distorted thin-deck panels. The method achieves a minimum geometric reconstruction accuracy of 0.08 mm and structural strain predictions mostly within 89% accuracy, validated against uni-axial monotonic tensile experiments on full-scale panels. Additionally, the proposed procedure reduces the file size to less than 1% of the original, thus representing a valuable solution for the handling of large sets of data from the scanning of multiple decks in ship superstructures. These results highlight the method’s potential for improving the assessment and quality control of thin-walled ship superstructures.Peer reviewe

Numerical implementation of the partial secular approximation and unified master equation in structured open quantum systems

The Markovian dynamics of open quantum systems is typically described through Lindblad equations, which are derived from the Redfield equation via the full secular approximation. The latter neglects the rotating terms in the master equation corresponding to pairs of jump operators with different Bohr frequencies. However, for many physical systems this approximation breaks down, and thus a more accurate treatment of the slowly rotating terms is required. Indeed, more precise physical results can be obtained by performing the partial secular approximation, which takes into account the relevant time scale associated with each pair of jump operators and compares it with the time scale arising from the system-environment coupling. In this work, we introduce a general code for performing the partial secular approximation in the Redfield equation for structured open quantum systems. The code can be applied to a generic Hamiltonian of any multipartite system coupled to bosonic baths. Moreover, it can also reproduce the unified master equation, which captures the same physical behavior as the Redfield equation under the partial secular approximation, but is mathematically guaranteed to generate a completely positive dynamical map. Finally, the code can compute both the local and global version of the master equation for the same physical problem. We illustrate the code by studying the steady-state heat flow in a structured open quantum system composed of two superconducting qubits, each coupled to a bosonic mode, which in turn interacts with a thermal bath. The results in this work can be employed for the numerical study of a wide range of complex open quantum systems.Peer reviewe

Convex body domination for rough singular integrals

Publisher Copyright: © 2025 The AuthorConvex body domination is a technique, where operators acting on vector-valued functions are estimated via certain convex body averages of the input functions. This domination lets one deduce various matrix weighted bounds for these operators and their commutators. In this paper, we extend the sparse domination results for rough singular integrals due to Conde-Alonso, Culiuc, Di Plinio and Ou to the convex body setting. In particular, our methods apply to homogeneous rough singular integrals with unbounded angular part. We also note that convex body domination implies new two weight commutator bounds even in the scalar case.Peer reviewe

Evaluating the impact of district-level microclimate, urban microenvironment and occupant behaviour upon overheating of Nordic apartment buildings

| openaire: EC/H2020/856602/EU//FINEST TWINS Publisher Copyright: Copyright © 2025. Published by Elsevier B.V.Climate change has amplified the frequency and intensity of heatwaves in Nordic countries, inducing a strong thermal discomfort in buildings that are optimized for cold climates. Most existing studies either isolate urban microenvironment factors or building-scale dynamics, ignoring their combined impact on indoor thermal environments, while currently used climate datasets typically ignore differences at the district level. Aiming to fill this gap, this work combines the impact of urban microenvironmental factors, building characteristics, and occupant behaviour on indoor overheating during heatwaves in the Helsinki region. Validated computer simulations mapping temperature variations at room, apartment, building, and district scales, showed that greenery and building density can substantially reduce indoor temperatures by up to 1.2 °C. At the building and apartment scales, limited wind exposure and intensified solar radiation induce instead overheating in middle-floor apartments and on south-facing façades by up to 0.8 °C. Passive cooling measures and mechanical balanced ventilation can partially moderate overheating, whilst occupant behaviour crucially reduces the indoor temperatures by up to 4.5 °C through optimal balcony doors and windows operation. Active cooling is therefore essential, with required capacities ranging from 200–850 W per room, spiking to ∼2000 W in scenarios with suboptimal occupant behaviour. These specific findings offer actionable insights for urban planners, architects, and policymakers towards optimized building design, strategic urban planning, and integration of active cooling systems. The methodology here introduced, grounded on high-resolution weather data and comprehensive computer simulations, is general and can be easily applied to other climates as well.Peer reviewe

QoE-Driven Resource Management Framework for Next-Generation Mobile Networks

Publisher Copyright: © The Author(s), under exclusive licence to Springer Nature Singapore Pte Ltd. 2025.Due to the massive growth in global data traffic, next-generation wireless communication technologies must meet the demands of emerging applications and services by providing enhanced Quality-of-Service (QoS) levels to end-users, by enabling a ubiquitous cellular coverage, characterized by ultra-high reliability and minimal latency. Notably, most cellular network traffic comes from densely populated urban areas, where dense infrastructure and high user demands lead to interference-limited conditions and competition for radio resources, resulting in degraded QoS levels for mobile User Equipment (UE). This work proposed a Quality-of-Experience (QoE)-driven framework for defining UE types according to defined QoS requirements, with application-specific diverse value-oriented services. The proposed framework primarily focuses on assessing cellular network performance with a user-centric approach via subjective metrics like end-user satisfaction, rather than solely on traditional communication-centric metrics. The proposed scheduling framework integrates a theoretical approach to guarantee QoS for various mobile UE types by dynamically allocating the necessary bandwidth resources. This also ensures guaranteed optimal performance for UEs, along with the minimal impact on the operational efficiency of UEs without specific service requirements.Peer reviewe

A CCP-Based Distributed Cooperative Operation Strategy for Multi-Agent Energy Systems Integrated with Wind, Solar, and Buildings

To explore the bidirectional interaction between renewable energy and buildings in multi-agent energy systems, this paper proposes a distributed cooperative operation strategy for multi-agent energy systems integrated with wind, solar, and buildings based on chance-constrained programming (CCP). First, the multi-agent energy system integrated with wind, solar, and buildings is comprehensively modeled with detailed electric and thermal characteristics for flexibility enhancement. Then for maximizing the profits of the cooperative energy system and each engaged agent, a Nash bargaining model is presented and is divided into two subproblems: the coalition income and the power payment. To preserve the privacy of agents, the adaptive alternating direction method of multipliers (ADMM) is exploited to solve both subproblems. Meanwhile, the CCP method is applied to address diverse uncertainties from wind and solar power generation as well as outdoor temperature. Finally, the effectiveness of the proposed strategy is validated. The simulation results show that, besides the privacy of information among all agents being well preserved, our strategy enhances the profits not only for the energy system but also for all engaged agents.Peer reviewe

BaO-modified finger-like nickel-based anode for enhanced performance and durability of direct carbon solid oxide fuel cells

Publisher Copyright: © 2024 Elsevier LtdDirect carbon solid oxide fuel cells (DC-SOFCs) are hopeful high-temperature energy conversion devices with all-solid-state structure, high efficiency, and low emission. The anode catalytic activity is a direct limiting factor in the electrochemical performance of DC-SOFCs. Here, we successfully fabricated a finger-like Ni-based anode/electrolyte in one step, followed by infiltrating BaO within the anode, which significantly improved the anodic reaction and DC-SOFC performance. At 850 °C, the BaO/Ni-YSZ anode-supported DC-SOFC gave the optimal output of 505 and 825 mW cm−2 powering by activated carbon and hydrogen, respectively, which were significantly superior to those of the cell with traditional Ni-YSZ anode. Moreover, DC-SOFC with BaO/Ni-YSZ anode exhibited more stable operation for 20.9 h under 100 mA at 850 °C, giving a relatively high fuel utilization of 23.4 %. These excellent performances can be partially attributed to the smaller particle sizes and more grain boundaries of the BaO/Ni-YSZ anode due to the BaO infiltration, which effectively enhanced the ionic conductivity and mechanical strength of the anode. More importantly, density functional theory simulation revealed that the infiltrated BaO in the Ni-YSZ anode enhanced the adsorption ability of Ni sites for carbon monoxide and oxygen ions, which led to the increased differential charge densities and the reduction in the energy barrier of electrochemical oxidation reaction, thus effectively improving DC-SOFC performance and conversion efficiency.Peer reviewe

ArtSampo – Finnish Art on the Semantic Web

Publisher Copyright: © The Author(s), under exclusive license to Springer Nature Switzerland AG 2025.This paper presents first results of ArtSampo, a collaborative Finnish Linked Open Data (LOD) infrastructure for publishing fine art collections on the Semantic Web and for facilitating Digital Humanities (DH) research. The infrastructure consists of a Knowledge Graph (KG) whose initial version was compiled from the metadata of the three art museums of the Finnish National Gallery. A semantic ArtSampo portal was built on top of the KG for searching, browsing, and analyzing the underlying data. The Finnish ontology infrastructure and international datasets are used for harmonizing and enriching the data.Peer reviewe