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T-ROBUST METHOD. Robustness-based multi-criteria decision-making methodology: Description and example of application
Get PDFThe focus on performance robustness has become paramount in the context of buildings and neighbourhoods, where uncertainties from variables like occupancy and weather scenarios significantly impact their performance.
Selecting a building/neighbourhood design that excels in both performance and robustness poses a challenge, particularly when multiple performance criteria must be met. In general, this requires a three stages process involving performance evaluation, robustness assessment, and multi-criteria decision-making.
This report introduces a novel robustness-based decision-making approach, which integrates robustness assessment and decision-making steps, offering greater transparency compared to existing methodologies. The developed approach has been previously described and applied in scientific dissemination, while this report strives to simplify the communication for a slightly broader audience than the scientific community, while alsoproviding practical guidance and instructions for implementing the method.
This approach has been tested for assessing different responsive building envelope (RBE) technologies within a Norwegian zero-emission building (ZEB lab). The approach evaluates five competitive RBE designs (including building integrated photovoltaics, phase change material, and electrochromic windows) across eight occupancy and climate scenarios, considering three performance indicators, i.e., energy use, thermal comfort, and load matching.
Results show that the suggested approach can effectively support the choice of a building/-neighbourhood design that is both high-performing and robust, requiring less analysis effort. Moreover, the proposed approach exhibits a high level of reliability, by selecting solutions in alignment with defined targets and demonstrating less dependency on scenario conditions.publishedVersio
Optimal Industrial Clusters: Flex4Fact Summer Research Report
Get PDFWe study the integration of digitization, smart scheduling, local renewable energy production, and variable energy prices in different industrial com panies to make an optimization entity for industrial cluster energy use. We discuss two energy optimization approaches: a centralized choice for all energy consumption and local-level trading of energy surplus and develop a graph-based package to implement these mechanisms given mixed-integer programming models for each of the firms. Testing our modeling package with data from the EU project Flex4Fact, we show that clustering decreases aggregate costs due to the lack of sell-back penalties, and the relative be nefit among firms depends on internal prices.publishedVersio
Hydrogen in Glass Sector: A Comparison between Risk-Based Maintenance and Time-Based Maintenance Approaches
Get PDFHydrogen can be the key to decarbonisation, even for energy-intensive industries. The glass sector, for instance, burns natural gas to reach high temperatures necessary to melt the raw materials, leading to a considerable amount of CO2 emissions. Introducing hydrogen in a new sector brings many challenges in technological development, but of no less importance are the safety issues due to its hazardous properties. Hydrogen is highly flammable and can interact with many metals. Avoiding hydrogen leaks or, even worse, preventing catastrophic losses should be a priority: adopting proper maintenance planning is an effective means. In this study, a comparison of two different maintenance approaches is proposed in a line supplying hydrogen to the furnace case study. Time-based maintenance is a consolidated technique that programs the operations based on the reliability of the data on the pieces of equipment. On the other hand, the Risk-Based Maintenance approach leads to planning the maintenance activities based on the risk evaluation. Applying this approach to a hydrogen facility for the first time represents the novelty of this study. The advantages of adopting a methodology based on risk evaluation when handling a safety-critical system are highlighted. Keywords: Hydrogen, Glass manufacturing, Maintenance, Risk-Based Maintenance, Time-Based Maintenance, Hydrogen Safety.Hydrogen in Glass Sector: A Comparison between Risk-Based Maintenance and Time-Based Maintenance ApproachespublishedVersio
Progressive Weakening of Granite by Piezoelectric Excitation of Quartz with Alternating Current
Get PDFA promising solution to reduce energy usage and mitigate the wear of drilling and comminution tools during mining operations involves inducing vibrations within the piezoelectric phases dispersed in the structure of rocks using alternating current (AC). This paper presents experimental evidence of AC-induced weakening of Kuru granite, manifested as improvements in rock drillability and reductions of strength. Sievers’ J-miniature drill tests were used to assess surface drillability. The impact of AC treatment on the quasi-static strength of granite was assessed via three-point bending and indirect tension Brazilian disk tests. The influence of AC treatment on the dynamic tensile strength of the rock was determined using split Hopkinson bar tests, with the fragmentation process captured using in situ ultra-fast synchrotron X-ray phase contrast imaging. The quasi-static tests revealed no reduction in rock strength after the AC treatment. In contrast, reductions of 25% in hardness and 18% in dynamic tensile strength were observed. Fragmentation patterns differed between treated and non-treated rocks, with treated specimens exhibiting reduced macrocrack formation during loading.publishedVersio
Direct Tungsten Extraction from Scheelite in a Molten Salt Media
Get PDFTungsten is a basic metal commodity that is classified as critical raw material (CRM) by the European Commission (EC) with the highest economical importance compared to other CRM. Thanks to its unique properties, secure W supply is critical to all industrial applications involving cutting or component wear, such as mining, machining, construction, tools and dies. Other important uses are in high-strength steels and high-temperature alloys, chemicals, mill products and lighting filaments. The production of W metal or carbide to be used in end products, requires a reduction process of the oxide which has been previously extracted from the primary (ores) resources by complex and energy intensive hydrometallurgical processes.
In the frame of the EC-funded TARANTULA project (GA 821159), innovative methods to obtain W metal directly from scheelite raw material have been investigated. The process comprises two steps, i.e., selective chlorination of the W ore in a molten chloride media using gaseous reactants, and subsequent electrolysis of the dissolved W electroactive species from the same reaction media. The chlorination of natural scheelite in a molten chloride has been demonstrated in the equimolar NaCl-KCl mixture at a working temperature of 727 °C, using both Cl2 (g) and HCl (g). The dissolved W species in the molten chloride were found to be tri-tungstate: W3O102− and/or the chloro-complex, as e.g., W3O10Cl24−. Subsequent electrolysis trials demonstrated the recovery of WC2 deposits on a carbonaceous cathode, while the anode reaction was evidenced to include the discharge of the oxide ions from the dissolved tri-tungstate species.publishedVersio
Dybdestudie busskjøring. En analyse og beskrivelse av hvordan bussjåfører løser arbeidsoppgavene og gjennomfører kjøringen basert på en forståelse av kjøreprosessen
Get PDFStudien undersøker hvordan bussjåførers arbeidshverdag påvirkes av kognitive, fysiske og emosjonelle faktorer. Kjøreprosessen er en handlingsorientert modell for kjøreatferd som kombinerer praktisk kjøreatferd med mentale prosesser (kognitive og emosjonelle) på en helhetlig måte. En hovedutfordring er å balansere tidspress og sikkerhet, særlig i rushtid med høy mental belastning. Eyetracking-data viser at sjåførene har flere blikk-fikseringer i rushtid for å holde oversikt over passasjerer og risikofaktorer. Dårlig infrastruktur med hull i veier og manglende merking utgjør sikkerhets- og helserisiko og fører til slitasje og stress. Positive sider er gode passasjerrelasjoner, følelsen av å bidra positivt og meningsfullt samtidig som sjåførene utrykker kjøregledepublishedVersio
SEA4DQ 2024 Workshop Summary
Get PDFWelcome to the sixth edition of the workshop on Machine Learning Techniques for Software Quality Evaluation (SEA4DQ 2024), held in Brazil, July 16th, 2024, co-located with ESEC / FSE 2024 [1]. Three papers from all over the world were submitted, and all of them were accepted based on the overall positive reviews. The program also featured two keynotes by Denys Poshyvanyk on Towards an Interpretable Science of Deep Learning for Software Engineering: A Causal Inference View and Qinghua Lu on Responsible AI Engineering from A Data Perspective.acceptedVersio
Automated segmentation of the median nerve in patients with carpal tunnel syndrome
Get PDFMachine learning and deep learning are novel methods which are revolutionizing medical imaging. In our study we trained an algorithm with a U-Net shaped network to recognize ultrasound images of the median nerve in the complete distal half of the forearm and to measure the cross-sectional area at the inlet of the carpal tunnel. Images of 25 patient hands with carpal tunnel syndrome (CTS) and 26 healthy controls were recorded on a video loop covering 15 cm of the distal forearm and 2355 images were manually segmented. We found an average Dice score of 0.76 between manual and automated segmentation of the median nerve in its complete course, while the measurement of the cross-sectional area at the carpal tunnel inlet resulted in a 10.9% difference between manually and automated measurements. We regard this technology as a suitable device for verifying the diagnosis of CTS.publishedVersio
Understanding automation transparency and its adaptive design implications in safety–critical systems
Get PDFAutomation is designed to assist operators and enhance system performance and safety. When unexpected events occur, and the operator is not able to understand the behaviour of the automated system a sudden rise in cognitive workload occurs, compromising decision-making, performance, and safety. Automation transparency as a human-centric design principle is a potential intervention in the design of human-automation systems that can remedy these countereffects. Human-centricity of advanced automated systems is one of the focal areas of Industry 5.0 and automation transparency is a potential design principle that will become even more important in this new era. Thus, this concept must be well-understood, and its design implications must be highlighted. This understanding of the current state of automation transparency is important for entering a new era with more complex systems. The literature includes varied definition and approaches to transparency with mixed results on its influence on automation system design factors, making it hard to understand design implications. This paper addresses this need. This work stemmed from a broader systematic literature review and specifically zoomed in on the included literature that explicitly mentioned the terms ‘automation transparency’ and ‘transparency’ in their abstracts and filtered for these articles in Rayyan software. These articles were screened for full text relevance, being empirical papers, using qualitative, quantitative or mixed methods. Fourteen resulting articles were analysed, as representative exemplars of empirical and recent work in this field, to see how automation transparency is being understood, what is its significance in relation to other automation system design factors, and what are the design implications. The findings showed a progressive trend from the emphasis on static, high transparency towards an emphasis on human centred adaptive transparency and explainability which is aligned with the focus of Industry 5.0. Adaptive transparency design implications derived from the analysis are presented along with limitations of the current research and the future research implications.publishedVersio
