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Aharonson, V., Christodoulou, V., Karpasitis, C., Joselowitz, J., Nowaczyk, S., Lazebnik, T. & Iordanou, K. (2026). Audience engagement with climate change content on YouTube: an analysis of video attributes and user interactions. Frontiers In Climate, 8, 1-10, Article ID 1803829.
Öppna denna publikation i ny flik eller fönster >>Audience engagement with climate change content on YouTube: an analysis of video attributes and user interactions
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2026 (Engelska)Ingår i: Frontiers In Climate, E-ISSN 2624-9553, Vol. 8, s. 1-10, artikel-id 1803829Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

Effective public engagement with climate change is central to advancing sustainability goals, yet the factors shaping audience responses to climate-related digital content remain insufficiently understood. This study investigates how presenter identity, message framing, and interaction structure influence audience engagement with climate change videos on YouTube. Using a mixed-methods approach, we analysed 129 English-language YouTube videos and their associated user comments, combining manual coding of video attributes with natural language processing and supervised machine learning to analyse comment sentiment. A binary logistic regression model was used to predict positive versus negative audience attitudes at the video level, with chi-square tests employed as supporting analyses. Results indicate that videos presented by scientists are significantly more likely to elicit positive audience attitudes than those presented by politicians or other public figures. Solution-focused framing is strongly associated with positive engagement, while blame-oriented framing is associated with negative responses. Additionally, threaded comment discussions show a higher proportion of positive attitudes than independent comments, suggesting that conversational interaction enhances constructive engagement. These findings highlight the importance of expertise-based communication, solution-oriented narratives, and interactive discourse in digital sustainability communication. The study contributes both methodological tools and practical insights for designing climate change communication strategies that foster informed and constructive public engagement. © 2026 Aharonson, Christodoulou, Karpasitis, Joselowitz, Nowaczyk, Lazebnik and Iordanou.

Ort, förlag, år, upplaga, sidor
Lausanne: Frontiers Media S.A., 2026
Nyckelord
computational social science, digital sustainability, environmental communication, online discourse, public engagement, sentiment mining
Nationell ämneskategori
Medie- och kommunikationsvetenskap
Identifikatorer
urn:nbn:se:hh:diva-59100 (URN)10.3389/fclim.2026.1803829 (DOI)001768734000001 ()
Tillgänglig från: 2026-06-02 Skapad: 2026-06-02 Senast uppdaterad: 2026-06-02Bibliografiskt granskad
Fukuhara, S., Alabdallah, A., Gunasekara, N. & Nowaczyk, S. (2026). Bridging Forecast Accuracy and Inventory KPIs: A Simulation-Based Software Framework. In: Mitra Baratchi; Siegfried Nijssen; Jan N. van Rijn (Ed.), Advances in Intelligent Data Analysis XXIV: Proceedings. Paper presented at 24th International Symposium on Intelligent Data Analysis, IDA 2026 Leiden, The Netherlands, April 22-24, 2026 (pp. 438-452). Heidelberg: Springer
Öppna denna publikation i ny flik eller fönster >>Bridging Forecast Accuracy and Inventory KPIs: A Simulation-Based Software Framework
2026 (Engelska)Ingår i: Advances in Intelligent Data Analysis XXIV: Proceedings / [ed] Mitra Baratchi; Siegfried Nijssen; Jan N. van Rijn, Heidelberg: Springer, 2026, s. 438-452Konferensbidrag, Publicerat paper (Refereegranskat)
Abstract [en]

Efficient management of spare parts inventory is crucial in the automotive aftermarket, where demand is highly intermittent, and uncertainty drives substantial cost and service risks. Forecasting is therefore central, but the quality of a forecasting model should be judged not by statistical accuracy (e.g., MAE, RMSE, IAE) but rather by its impact on key operational performance indicators (KPIs), such as total cost and service level. Yet most existing work evaluates models exclusively using accuracy metrics, and the relationship between these metrics and operational KPIs remains poorly understood. To address this gap, we propose a decision-centric simulation software framework that enables the systematic evaluation of forecasting models in realistic inventory management settings. The framework comprises: (i) a synthetic demand generator tailored to spare-parts demand characteristics, (ii) a flexible forecasting module that can host arbitrary predictive models, and (iii) an inventory control simulator that consumes the forecasts and computes, based on selected inventory control policy, operational KPIs. This closed-loop setup enables practitioners and researchers to evaluate models not only in terms of statistical error but also in terms of their downstream implications for inventory decisions. Using a wide range of simulation scenarios, we show that improvements in conventional accuracy metrics do not necessarily translate into better operational performance, and that models with similar statistical error profiles can induce markedly different cost–service trade-offs. We analyze these discrepancies to characterize how specific aspects of forecast performance affect inventory outcomes and to derive actionable guidance for model selection. Overall, the framework operationalizes the link between demand forecasting and inventory management, shifting evaluation from purely predictive accuracy towards operational relevance in the automotive aftermarket and related domains. An open-source implementation of the software, including all experimental results, is available at https://github.com/caisr-hh/TruckParts-Demand-Inventory-Simulator/releases/tag/IDA_2026. © The Author(s), under exclusive license to Springer Nature Switzerland AG 2026.

Ort, förlag, år, upplaga, sidor
Heidelberg: Springer, 2026
Serie
Lecture Notes in Computer Science, ISSN 0302-9743, E-ISSN 1611-3349 ; 16513
Nyckelord
Aftermarket logistics, Demand forecasting, Inventory management, Simulation, Spare parts demand, Synthetic data generation
Nationell ämneskategori
Transportteknik och logistik
Identifikatorer
urn:nbn:se:hh:diva-58984 (URN)10.1007/978-3-032-23833-7_32 (DOI)2-s2.0-105037458118 (Scopus ID)978-3-032-23833-7 (ISBN)978-3-032-23832-0 (ISBN)
Konferens
24th International Symposium on Intelligent Data Analysis, IDA 2026 Leiden, The Netherlands, April 22-24, 2026
Tillgänglig från: 2026-06-05 Skapad: 2026-06-05 Senast uppdaterad: 2026-06-05Bibliografiskt granskad
Starck, H., Tran, N. A. & Nowaczyk, S. (2026). Deep Decision Forest. In: Mitra Baratchi; Siegfried Nijssen; Jan N. van Rijn (Ed.), Advances in Intelligent Data Analysis XXIV: 24th International Symposium on Intelligent Data Analysis, IDA 2026 Leiden, The Netherlands, April 22–24, 2026, Proceedings. Paper presented at 24th International Symposium on Intelligent Data Analysis, IDA 2026, Leiden, The Netherlands, April 22–24, 2026 (pp. 185-198). Cham: Springer
Öppna denna publikation i ny flik eller fönster >>Deep Decision Forest
2026 (Engelska)Ingår i: Advances in Intelligent Data Analysis XXIV: 24th International Symposium on Intelligent Data Analysis, IDA 2026 Leiden, The Netherlands, April 22–24, 2026, Proceedings / [ed] Mitra Baratchi; Siegfried Nijssen; Jan N. van Rijn, Cham: Springer, 2026, s. 185-198Konferensbidrag, Publicerat paper (Refereegranskat)
Abstract [en]

Deep learning has demonstrated success in domains such as vision and speech, largely due to its ability to learn hierarchical feature representations via backpropagation. However, tree-based models, such as Random Forest and XGBoost, remain dominant for tabular data, often, but not always, outperforming deep Artificial Neural Networks (ANNs) while requiring less computational resources. It has been demonstrated that neural networks are particularly effective for data that is less heavily preprocessed and that contains important yet complex feature dependencies. This paper introduces Deep Decision Forest (DDF), a multilayer decision tree ensemble that bridges this gap by incorporating a feedback mechanism analogous to backpropagation. We postulate that such a mechanism will enable tree-based models to capture hierarchical feature representations to a degree that was previously impossible. Each layer of trees produces an output vector that serves as the input features for subsequent layers, and final predictions are obtained through majority voting in the last layer. One key difference between tree-based models and ANNs is that, instead of making minor adjustments to all the numeric weights at once, DDF first identifies the most underperforming features across layers, and selectively retrains only the corresponding trees using specialised improvement datasets. Experiments on seven benchmark datasets demonstrate that DDF consistently outperforms a standard Decision Tree, performs as well as or better than Random Forest, and achieves competitive accuracy compared to Deep Forest. These experiments demonstrate that integrating elements inspired by deep learning into tree ensembles is both feasible and effective, offering a new hybrid approach for tabular learning. All the code and experiments are available open source at: https://github.com/caisr-hh/Deep-Decision-Forest. © The Author(s), under exclusive license to Springer Nature Switzerland AG 2026.

Ort, förlag, år, upplaga, sidor
Cham: Springer, 2026
Serie
Lecture Notes in Computer Science, ISSN 0302-9743, E-ISSN 1611-3349 ; 16513
Nyckelord
Decision Forest, Decision Tree, Deep Decision Forest
Nationell ämneskategori
Datavetenskap (datalogi) Datorgrafik och datorseende
Identifikatorer
urn:nbn:se:hh:diva-58989 (URN)10.1007/978-3-032-23833-7_14 (DOI)2-s2.0-105037444519 (Scopus ID)978-3-032-23832-0 (ISBN)978-3-032-23833-7 (ISBN)
Konferens
24th International Symposium on Intelligent Data Analysis, IDA 2026, Leiden, The Netherlands, April 22–24, 2026
Forskningsfinansiär
VinnovaKK-stiftelsen
Tillgänglig från: 2026-06-12 Skapad: 2026-06-12 Senast uppdaterad: 2026-06-12Bibliografiskt granskad
Fan, Y., Wang, Z., Pashami, S., Nowaczyk, S. & Ydreskog, H. (2026). Forecasting Auxiliary Energy Consumption for Electric Heavy-Duty Vehicles. In: Danguolė Mattia Cerrato; Mantas Kalinauskaitė; Mykola Lukoševičius; Kristina Šutienė Pechenizkiy (Ed.), Machine Learning and Principles and Practice of Knowledge Discovery in Databases: International Workshops of ECML PKDD 2024, Vilnius, Lithuania, September 9–13, 2024, Revised Selected Papers, Part IV. Paper presented at 24th Joint European Conference on Machine Learning and Knowledge Discovery in Databases, ECML PKDD 2024, Vilnius, Lithuania, 9-13 September, 2024 (pp. 355-367). Heidelberg: Springer, 2561 CCIS
Öppna denna publikation i ny flik eller fönster >>Forecasting Auxiliary Energy Consumption for Electric Heavy-Duty Vehicles
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2026 (Engelska)Ingår i: Machine Learning and Principles and Practice of Knowledge Discovery in Databases: International Workshops of ECML PKDD 2024, Vilnius, Lithuania, September 9–13, 2024, Revised Selected Papers, Part IV / [ed] Danguolė Mattia Cerrato; Mantas Kalinauskaitė; Mykola Lukoševičius; Kristina Šutienė Pechenizkiy, Heidelberg: Springer, 2026, Vol. 2561 CCIS, s. 355-367Konferensbidrag, Publicerat paper (Refereegranskat)
Abstract [en]

Accurate energy consumption prediction is crucial for optimizing the operation of electric commercial heavy-duty vehicles, e.g., route planning for charging. Moreover, understanding why certain predictions are cast is paramount for such a predictive model to gain user trust and be deployed in practice. Since commercial vehicles operate differently as transportation tasks, ambient, and drivers vary, a heterogeneous population is expected when building an AI system for forecasting energy consumption. The dependencies between the input features and the target values are expected to also differ across sub-populations. One well-known example of such a statistical phenomenon is Simpson’s paradox. In this paper, we illustrate that such a setting poses a challenge for existing XAI methods that produce global feature statistics, e.g., LIME or SHAP, causing them to yield misleading results. We demonstrate a potential solution by training multiple regression models on subsets of data via a divide-and-conquer approach. It not only leads to superior regression performance but also more relevant and consistent LIME explanations. Given that the employed groupings correspond to relevant sub-populations, the associations between the input features and the target values are consistent within each cluster but different across clusters. Experiments on both synthetic and real-world datasets show that such splitting of a complex problem into simpler ones yields better regression performance and interpretability. © The Author(s), under exclusive license to Springer Nature Switzerland AG 2026.

Ort, förlag, år, upplaga, sidor
Heidelberg: Springer, 2026
Serie
Communications in Computer and Information Science, ISSN 1865-0929, E-ISSN 1865-0937
Nyckelord
Energy Consumption Prediction, Explainable Predictive Maintenance
Nationell ämneskategori
Datavetenskap (datalogi) Transportteknik och logistik
Identifikatorer
urn:nbn:se:hh:diva-59366 (URN)10.1007/978-3-032-25314-9_25 (DOI)2-s2.0-105040334047 (Scopus ID)978-3-032-25313-2 (ISBN)978-3-032-25314-9 (ISBN)
Konferens
24th Joint European Conference on Machine Learning and Knowledge Discovery in Databases, ECML PKDD 2024, Vilnius, Lithuania, 9-13 September, 2024
Tillgänglig från: 2026-06-15 Skapad: 2026-06-15 Senast uppdaterad: 2026-06-15Bibliografiskt granskad
Galozy, A., Nowaczyk, S. & Ohlsson, M. (2025). A new bandit setting balancing information from state evolution and corrupted context. Data mining and knowledge discovery, 39(1), Article ID 9.
Öppna denna publikation i ny flik eller fönster >>A new bandit setting balancing information from state evolution and corrupted context
2025 (Engelska)Ingår i: Data mining and knowledge discovery, ISSN 1384-5810, E-ISSN 1573-756X, Vol. 39, nr 1, artikel-id 9Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

We propose a new sequential decision-making setting, combining key aspects of two established online learning problems with bandit feedback. The optimal action to play at any given moment is contingent on an underlying changing state that is not directly observable by the agent. Each state is associated with a context distribution, possibly corrupted, allowing the agent to identify the state. Furthermore, states evolve in a Markovian fashion, providing useful information to estimate the current state via state history. In the proposed problem setting, we tackle the challenge of deciding on which of the two sources of information the agent should base its action selection. We present an algorithm that uses a referee to dynamically combine the policies of a contextual bandit and a multi-armed bandit. We capture the time-correlation of states through iteratively learning the action-reward transition model, allowing for efficient exploration of actions. Our setting is motivated by adaptive mobile health (mHealth) interventions. Users transition through different, time-correlated, but only partially observable internal states, determining their current needs. The side information associated with each internal state might not always be reliable, and standard approaches solely rely on the context risk of incurring high regret. Similarly, some users might exhibit weaker correlations between subsequent states, leading to approaches that solely rely on state transitions risking the same. We analyze our setting and algorithm in terms of regret lower bound and upper bounds and evaluate our method on simulated medication adherence intervention data and several real-world data sets, showing improved empirical performance compared to several popular algorithms. © The Author(s) 2024.

Ort, förlag, år, upplaga, sidor
New York: Springer, 2025
Nyckelord
Contextual bandit, Markov property, Multi-armed-bandit, Non-stationary
Nationell ämneskategori
Artificiell intelligens
Identifikatorer
urn:nbn:se:hh:diva-58209 (URN)10.1007/s10618-024-01082-3 (DOI)001380061500003 ()2-s2.0-85212582551 (Scopus ID)
Forskningsfinansiär
Vinnova, 2017-04617Högskolan i Halmstad
Tillgänglig från: 2026-01-23 Skapad: 2026-01-23 Senast uppdaterad: 2026-01-27Bibliografiskt granskad
Özen, C., Nowaczyk, S., Tiwari, P. & Pashami, S. (2025). Assessing the Graph Structure Learning in Graph Deviation Networks. In: Georg Krempl; Kai Puolamäki; Ioanna Miliou (Ed.), Advances in Intelligent Data Analysis XXIII (IDA 2025): Proceedings. Paper presented at 23rd International Symposium on Intelligent Data Analysis, IDA 2025, Konstanz, Germany, 7-9 May, 2025 (pp. 97-109). Cham: Springer
Öppna denna publikation i ny flik eller fönster >>Assessing the Graph Structure Learning in Graph Deviation Networks
2025 (Engelska)Ingår i: Advances in Intelligent Data Analysis XXIII (IDA 2025): Proceedings / [ed] Georg Krempl; Kai Puolamäki; Ioanna Miliou, Cham: Springer, 2025, s. 97-109Konferensbidrag, Publicerat paper (Refereegranskat)
Abstract [en]

Statistical modeling of multivariate time-series data poses significant challenges due to their high dimensionality and complex inter-variable relationships. Reliable forecasts or anomaly detection on these datasets require capturing such relationships within and between the features. While traditional deep learning architectures are good at capturing temporal non-linear patterns within features, they are less efficient at modeling inter-variable relationships explicitly structured as graphs-a capability where Graph Neural Networks (GNNs) excel. Inspired by the success of GNNs, Graph Deviation Network (GDN) was originally proposed for anomaly detection on industrial multivariate time-series data. After proving its merits through experiments with real-world data, GDN gained significant popularity in the research community, claiming to learn the hidden graph structure in any multivariate time-series data. Various modifications to GDN were proposed over the years, but essentially all of them kept its Graph Structure Learning (GSL) module intact. However, until now, this module has never been rigorously evaluated. This work scrutinizes the contribution of the GSL module. Our experiments reveal that the graph learned by GSL is relatively ineffective, and the key to the overall performance achieved by GDN lies almost entirely in the downstream Graph Attention Network (GAT) module. We hope our findings will garner attention for further development of the GSL module of GDN, whose fidelity can improve the performance of GDN variants. © The Author(s), under exclusive license to Springer Nature Switzerland AG 2025.

Ort, förlag, år, upplaga, sidor
Cham: Springer, 2025
Serie
Lecture Notes in Computer Science ; 15669
Nyckelord
GNNs for Time-Series Anomaly Detection, Graph Deviation Network, Graph Neural Networks, Graph Structure Learning
Nationell ämneskategori
Datavetenskap (datalogi)
Forskningsämne
Smarta städer och samhällen, FIRP
Identifikatorer
urn:nbn:se:hh:diva-56289 (URN)10.1007/978-3-031-91398-3_8 (DOI)2-s2.0-105005282687 (Scopus ID)978-3-031-91397-6 (ISBN)978-3-031-91398-3 (ISBN)
Konferens
23rd International Symposium on Intelligent Data Analysis, IDA 2025, Konstanz, Germany, 7-9 May, 2025
Forskningsfinansiär
KK-stiftelsenVinnova
Tillgänglig från: 2025-07-08 Skapad: 2025-07-08 Senast uppdaterad: 2025-10-01Bibliografiskt granskad
Żarski, M. & Nowaczyk, S. (2025). Balancing Performance and Scalability of Demand Forecasting ML Models. In: Georg Krempl, Kai Puolamäki, Ioanna Miliou (Ed.), Advances in Intelligent Data Analysis XXIII: Proceedings. Paper presented at 23rd International Symposium on Intelligent Data Analysis, IDA 2025, Konstanz, Germany, May 7–9, 2025 (pp. 127-140). Cham: Springer
Öppna denna publikation i ny flik eller fönster >>Balancing Performance and Scalability of Demand Forecasting ML Models
2025 (Engelska)Ingår i: Advances in Intelligent Data Analysis XXIII: Proceedings / [ed] Georg Krempl, Kai Puolamäki, Ioanna Miliou, Cham: Springer, 2025, s. 127-140Konferensbidrag, Publicerat paper (Refereegranskat)
Abstract [en]

Balancing performance and scalability is a major concern when developing robust ML models for diverse, big-data scenarios, such as predicting demand for a number of products across multiple locations. The two mutually opposite approaches are to use a single ML model for maximizing scalability, often at the expense of performance, or to use a specialized model for each specific use case, which is often prohibitive in terms of computational costs. In this paper, we propose to balance those two approaches using our methods of model clustering and grouping. We achieve the performance level of a single use-case model while preserving the global scalability of the solution. In our experiments, we use a publicly available demand forecasting dataset as a use case. We develop and train baseline shallow ML models and DL models for both maximizing performance and scalability. Then, we showcase a desirable balance that can be achieved using our proposed methods, one that outperforms both shallow ML and specific use-case models. © The Author(s), under exclusive license to Springer Nature Switzerland AG 2025.

Ort, förlag, år, upplaga, sidor
Cham: Springer, 2025
Serie
Lecture Notes in Computer Science ; 15669
Nyckelord
Deep Learning, Demand forecasting, Hybrid models, Model fine-tuning, Transfer learning
Nationell ämneskategori
Datavetenskap (datalogi)
Forskningsämne
Smarta städer och samhällen, FIRP
Identifikatorer
urn:nbn:se:hh:diva-56290 (URN)10.1007/978-3-031-91398-3_10 (DOI)2-s2.0-105005274460 (Scopus ID)978-3-031-91397-6 (ISBN)978-3-031-91398-3 (ISBN)
Konferens
23rd International Symposium on Intelligent Data Analysis, IDA 2025, Konstanz, Germany, May 7–9, 2025
Tillgänglig från: 2025-07-14 Skapad: 2025-07-14 Senast uppdaterad: 2025-10-01Bibliografiskt granskad
Persson, D., Wahlberg, W., Vettoruzzo, A. & Nowaczyk, S. (2025). Bridging Spatial and Temporal Contexts: Sparse Transfer Learning. In: Georg Krempl, Kai Puolamäki, Ioanna Miliou (Ed.), Advances in Intelligent Data Analysis XXIII: Proceedings. Paper presented at 23rd International Symposium on Intelligent Data Analysis, IDA 2025, Konstanz, Germany, May 7–9, 2025. (pp. 330-342). Cham: Springer
Öppna denna publikation i ny flik eller fönster >>Bridging Spatial and Temporal Contexts: Sparse Transfer Learning
2025 (Engelska)Ingår i: Advances in Intelligent Data Analysis XXIII: Proceedings / [ed] Georg Krempl, Kai Puolamäki, Ioanna Miliou, Cham: Springer, 2025, s. 330-342Konferensbidrag, Publicerat paper (Refereegranskat)
Abstract [en]

This paper introduces a novel transfer learning adapter, the Bridged Attention Module (BAM), designed to enhance the performance of Spatial-Temporal Graph Convolutional Networks (ST-GCN) in data-limited forecasting scenarios. BAM improves fine-tuning efficiency by jointly capturing spatial and temporal dependencies, optimizing information flow, and significantly reducing the number of trainable parameters while preserving model accuracy. Experimental evaluations demonstrate that the BAM-enhanced ST-GCN consistently achieves competitive accuracy and, in some cases, surpasses traditional fine-tuning methods, even with limited data. The effectiveness of this approach is validated using electric vehicle (EV) charging station occupancy forecasting, highlighting the practical utility of BAM. © The Author(s), under exclusive license to Springer Nature Switzerland AG 2025.

Ort, förlag, år, upplaga, sidor
Cham: Springer, 2025
Serie
Lecture Notes in Computer Science ; 15669
Nyckelord
Deep learning, Electric vehicles, Parameter-efficient learning, Time series, Transfer learning
Nationell ämneskategori
Datavetenskap (datalogi)
Forskningsämne
Smarta städer och samhällen, FIRP
Identifikatorer
urn:nbn:se:hh:diva-56293 (URN)10.1007/978-3-031-91398-3_25 (DOI)2-s2.0-105005261280 (Scopus ID)978-3-031-91397-6 (ISBN)978-3-031-91398-3 (ISBN)
Konferens
23rd International Symposium on Intelligent Data Analysis, IDA 2025, Konstanz, Germany, May 7–9, 2025.
Tillgänglig från: 2025-07-14 Skapad: 2025-07-14 Senast uppdaterad: 2025-10-01Bibliografiskt granskad
Fan, Y., Camacho, C., Pashami, S. & Nowaczyk, S. (2025). Causal Graph-Based Anomaly Detection for Battery Modules in Electric Heavy-Duty Vehicles. In: Proceedings of the Asia Pacific Conference of the PHM Society 2025: . Paper presented at PHM Society Asia-Pacific Conference,Singapore, Singapore, December 8-11, 2025. The Prognostics and Health Management Society (PHM Society), 5, Article ID 1.
Öppna denna publikation i ny flik eller fönster >>Causal Graph-Based Anomaly Detection for Battery Modules in Electric Heavy-Duty Vehicles
2025 (Engelska)Ingår i: Proceedings of the Asia Pacific Conference of the PHM Society 2025, The Prognostics and Health Management Society (PHM Society) , 2025, Vol. 5, artikel-id 1Konferensbidrag, Publicerat paper (Refereegranskat)
Abstract [en]

Heavy-duty battery electric vehicles rely on large and complex energy storage systems (ESS), composed of multiple battery modules, whose individual health and reliability are critical to vehicle performance and safety. This study applies an unsupervised anomaly detection framework, COSMO (Consensus Self-Organizing Models), to a naturalistic real-world dataset collected during routine operations of in-service heavy-duty vehicles. We extend the baseline COSMO by incorporating causal discovery algorithms to help detect early signs of faults in ESS across heterogeneous missions and external conditions. On-board sensors data is collected as a multivariate time series, including information such as voltage, current, temperature, state of charge, etc. Given the wide range of applications of heavy-duty vehicles, these signals typically exhibit extreme variability even under normal operation, making anomaly detection challenging. Causal graph discovery allows us to acquire latent structures that capture the underlying relationships among these influential features. The resulting learned causal graphs, for each battery module, serve as a more consistent representation that captures each battery module’s usage and behavior over time. Since battery modules within the same ESS are expected to behave similarly under comparable operating conditions, COSMO models them as a homogeneous group. We then mark as anomalous modules that are identified to exhibit causal graph representations deviating markedly from the consensus.

Ort, förlag, år, upplaga, sidor
The Prognostics and Health Management Society (PHM Society), 2025
Serie
Proceedings of the Asia-Pacific Conference of the Prognostics and Health Management (PHM) Society, ISSN 2994-7219
Nyckelord
Causal inference, Anomaly detection, Battery prognostics, Causal graph
Nationell ämneskategori
Datorsystem Signalbehandling
Forskningsämne
Smarta städer och samhällen, FIRP
Identifikatorer
urn:nbn:se:hh:diva-58625 (URN)10.36001/phmap.2025.v5i1.4527 (DOI)
Konferens
PHM Society Asia-Pacific Conference,Singapore, Singapore, December 8-11, 2025
Tillgänglig från: 2026-03-26 Skapad: 2026-03-26 Senast uppdaterad: 2026-04-13Bibliografiskt granskad
Calikus, E., Nowaczyk, S. & Dikmen, O. (2025). Context Discovery for Anomaly Detection. International Journal of Data Science and Analytics, 19(1), 99-113
Öppna denna publikation i ny flik eller fönster >>Context Discovery for Anomaly Detection
2025 (Engelska)Ingår i: International Journal of Data Science and Analytics, ISSN 2364-415X, Vol. 19, nr 1, s. 99-113Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

Contextual anomaly detection aims to identify objects that are anomalous only within specific contexts, while appearing normal otherwise. However, most existing methods are limited to a single context defined by user-specified features. In practice, identifying the right context is not trivial, even for domain experts. Moreover, for high-dimensional data, the notion of meaningful contexts that can unveil anomalies becomes substantially more complex. For instance, multiple useful contexts can often capture different phenomena. In this work, we introduce ConQuest, a new unsupervised contextual anomaly detection approach that automatically discovers and incorporates multiple contexts useful for detecting and interpreting anomalies. Through experiments on 25 datasets, we show that ConQuest outperforms various state-of-the-art methods. We also demonstrate its benefits in terms of increased direct interpretability. © The Author(s) 2024.

Ort, förlag, år, upplaga, sidor
Heidelberg: Springer, 2025
Nyckelord
anomaly detection, contextual anomaly detection
Nationell ämneskategori
Datavetenskap (datalogi)
Forskningsämne
Smarta städer och samhällen
Identifikatorer
urn:nbn:se:hh:diva-46402 (URN)10.1007/s41060-024-00586-x (DOI)001250244900003 ()2-s2.0-85196295899 (Scopus ID)
Forskningsfinansiär
KK-stiftelsen, 20160103
Anmärkning

Som manuskript i avhandling / As manuscript in thesis.

Funding: Open access funding provided by Royal Institute of Technology.

Tillgänglig från: 2022-02-22 Skapad: 2022-02-22 Senast uppdaterad: 2025-10-01Bibliografiskt granskad
Projekt
iMedA: Improving MEDication Adherence through Person Centered Care and Adaptive Interventions [2017-04617_Vinnova]; Högskolan i Halmstad; Publikationer
Galozy, A. (2021). Data-driven personalized healthcare: Towards personalized interventions via reinforcement learning for Mobile Health. (Licentiate dissertation). Halmstad: Halmstad University PressGalozy, A., Nowaczyk, S., Pinheiro Sant'Anna, A., Ohlsson, M. & Lingman, M. (2020). Pitfalls of medication adherence approximation through EHR and pharmacy records: Definitions, data and computation. International Journal of Medical Informatics, 136, Article ID 104092. Galozy, A. & Nowaczyk, S. (2020). Prediction and pattern analysis of medication refill adherence through electronic health records and dispensation data. Journal of Biomedical Informatics: X, 6-7, Article ID 100075. Galozy, A., Nowaczyk, S. & Ohlsson, M.Corrupted Contextual Bandits with Action Order Constraints.
eXplainable Predictive Maintenance [2020-00767_VR]; Högskolan i Halmstad; Publikationer
Amirhossein, B., Taghiyarrenani, Z. & Nowaczyk, S. (2023). curr2vib: Modality Embedding Translation for Broken-Rotor Bar Detection. In: Irena Koprinska et al. (Ed.), Machine Learning and Principles and Practice of Knowledge Discovery in Databases: International Workshops of ECML PKDD 2022, Grenoble, France, September 19–23, 2022, Proceedings, Part II. Paper presented at ECML PKDD: Joint European Conference on Machine Learning and Knowledge Discovery in Databases, Grenoble, France, September 19–23, 2022 (pp. 423-437). Cham: Springer Nature, 1753Berenji, A., Nowaczyk, S. & Taghiyarrenani, Z. (2023). Data-Centric Perspective on Explainability Versus Performance Trade-Off. In: Bruno Crémilleux, Sibylle Hess, Siegfried Nijssen (Ed.), Advances in Intelligent Data Analysis XXI: 21st International Symposium on Intelligent Data Analysis, IDA 2023, Louvain-la-Neuve, Belgium, April 12–14, 2023, Proceedings. Paper presented at 21st International Symposium on Intelligent Data Analysis, IDA 2023, Louvain-la-Neuve, Belgium, April 12–14, 2023 (pp. 42-54). Cham: Springer, 13876Alabdallah, A., Pashami, S., Rögnvaldsson, T. & Ohlsson, M. (2022). SurvSHAP: A Proxy-Based Algorithm for Explaining Survival Models with SHAP. In: Joshua Zhexue Huang; Yi Pan; Barbara Hammer; Muhammad Khurram Khan; Xing Xie; Laizhong Cui; Yulin He (Ed.), 2022 IEEE 9th International Conference on Data Science and Advanced Analytics (DSAA): . Paper presented at The 9th IEEE International Conference on Data Science and Advanced Analytics (DSAA 2022), Shenzhen, China, October 13-16, 2022. Piscataway, NJ: IEEE
Automatic Idea Detection: Implementing artificial intelligence in medical technology innovation (AID); Högskolan i HalmstadFrom Connected to Sustainable Mobility (FREEDOM) [2021-02548_Vinnova]; Högskolan i HalmstadAI-driven Automotive Service Market: Towards more Resource-Efficient and Sustainable Vehicle Maintenance [2023-02594_Vinnova]; Högskolan i Halmstad
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