In this work, the concept of an Artificial Intelligence-based (AI) Digital Twin (DT) of an aircraft system is introduced, with the goal to improve the corresponding MRO Operations. More specifically, the current study aims to obtaining knowledge on the optimal placement of sensors in an ideal Power Electronics Cooling System (PECS) of a modern airliner, aiming to improve input data as a basis for an AI-based DT. The three main fluid parameters to be measured directly or indirectly at various physical locations at the PECS are mass flow rate, temperature and static pressure. The physics-based model can then be combined with a Machine Learning (ML) model, such as a Random Forest (RF), with a multitude of decision trees. Following, the AI system determines whether the PECS operations is considered normal, aiming to optimize the performance of the system and to maximize the Useful Remaining Life (URL). The suggested AI-DT approach is based both on data-driven and physics-based models, an approach which results in increased reliability and availability, reducing possible Aircraft on Ground (AOG) events. Subsequently, the enhanced prediction capability results in the optimization of the maintenance processes and in reduced operational costs.
History education frequently aims at developing active citizenship by using the past to orientate to the present and the future. A pedagogy for pursuing this aim is making connections between the past and the present by means of comparing cases of an enduring human issue. To examine the feasibility and desirability of this case-comparison teaching approach, students (N = 444) and teachers (N = 15) who participated in an implementation study conducted in the Netherlands were questioned about their experiences and views. Results show that both students and teachers felt that case-comparison in the context of an enduring human issue is feasible and not more complex than the usual history teaching in which topics are studied separately without explicitly making comparisons between past and present, even if some students thought that taking account of episodes from different historical periods concurrently required an extra learning effort. Both students and teachers believed that connecting past and present in history teaching enhances engagement and meaning making. They suggested a curriculum combining the case-comparison approach with the type of history teaching they were accustomed to. Mixed methods were used for data collection. Implications for further research on case-comparison learning in history are being discussed.
Many students persistently misinterpret histograms. This calls for closer inspection of students’ strategies when interpreting histograms and case-value plots (which look similar but are diferent). Using students’ gaze data, we ask: How and how well do upper secondary pre-university school students estimate and compare arithmetic means of histograms and case-value plots? We designed four item types: two requiring mean estimation and two requiring means comparison. Analysis of gaze data of 50 students (15–19 years old) solving these items was triangulated with data from cued recall. We found five strategies. Two hypothesized most common strategies for estimating means were confirmed: a strategy associated with horizontal gazes and a strategy associated with vertical gazes. A third, new, count-and-compute strategy was found. Two more strategies emerged for comparing means that take specific features of the distribution into account. In about half of the histogram tasks, students used correct strategies. Surprisingly, when comparing two case-value plots, some students used distribution features that are only relevant for histograms, such as symmetry. As several incorrect strategies related to how and where the data and the distribution of these data are depicted in histograms, future interventions should aim at supporting students in understanding these concepts in histograms. A methodological advantage of eye-tracking data collection is that it reveals more details about students’ problem-solving processes than thinking-aloud protocols. We speculate that spatial gaze data can be re-used to substantiate ideas about the sensorimotor origin of learning mathematics.
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In summer 2020, part of a quay wall in Amsterdam collapsed, and in 2010, construction for a parking lot in Amsterdam was hindered by old sewage lines. New sustainable electric systems are being built on top of the foundations of old windmills, in places where industry thrived in the 19th century. All these examples have one point in common: They involve largely unknown and invisible historic underground structures in a densely built historic city. We argue that truly circular building practices in old cities require smart interfaces that allow the circular use of data from the past when planning the future. The continuous use and reuse of the same plots of land stands in stark contrast with the discontinuity and dispersed nature of project-oriented information. Construction and data technology improves, but information about the past is incomplete. We have to break through the lack of historic continuity of data to make building practices truly circular. Future-oriented construction in Amsterdam requires historic knowledge and continuous documentation of interventions and findings over time. A web portal will bring together a range of diverse public and private, professional and citizen stakeholders, each with their own interests and needs. Two creative industry stakeholders, Yume interactive (Yume) and publisher NAI010, come together to work with a major engineering office (Witteveen+Bos), the AMS Institute, the office of Engineering of the Municipality of Amsterdam, UNESCO NL and two faculties of Delft University of Technology (Architecture and Computer Science) to inventorize historic datasets on the Amsterdam underground. The team will connect all the relevant stakeholders to develop a pilot methodology and a web portal connecting historic data sets for use in contemporary and future design. A book publication will document the process and outcomes, highlighting the need for circular practices that tie past, present and future.
