Publications
2025
Schultheis, Alexander; Bertrand, Yannis; Grüger, Joscha; Malburg, Lukas; Bergmann, Ralph; Asensio, Estefanía Serral
Case-based Data Quality Management for IoT Logs: A Case Study Focusing on Detection of Data Quality Issues Journal Article
In: IoT, vol. 6, no. 4, 2025.
Abstract | Links | BibTeX | Tags: Data Quality Issues, Industrial Internet of Things, Temporal Case-Based Reasoning, Time Series Data
@article{SchultheisBGMBSA2025,
title = {Case-based Data Quality Management for IoT Logs: A Case Study Focusing on Detection of Data Quality Issues},
author = {Alexander Schultheis and Yannis Bertrand and Joscha Grüger and Lukas Malburg and Ralph Bergmann and Estefanía Serral Asensio},
doi = {10.3390/iot6040063},
year = {2025},
date = {2025-01-01},
journal = {IoT},
volume = {6},
number = {4},
abstract = {Smart manufacturing applications increasingly rely on time-series data from Industrial IoT sensors, yet these data streams often contain data quality issues (DQIs) that affect analysis and disrupt production. While traditional Machine Learning methods are difficult to apply due to the small amount of data available, the knowledge-based approach of Case-Based Reasoning (CBR) offers a way to reuse previously gained experience. We introduce the first end-to-end Case-Based Reasoning (CBR) framework that both detects and remedies DQIs in near real time, even when only a handful of annotated fault instances are available. Our solution encodes expert experience in the four CBR knowledge containers: (i) a vocabulary that represents sensor streams and their context in the DataStream format; (ii) a case base populated with fault-annotated event logs; (iii) tailored similarity measures—including a weighted Dynamic Time Warping variant and structure-aware list mapping—that isolate the signatures of missing-value, missing-sensor, and time-shift errors; and (iv) lightweight adaptation rules that recommend concrete repair actions or, where appropriate, invoke automated imputation and alignment routines. A case study is used to examine and present the suitability of the approach for a specific application domain. Although the case study demonstrates only limited capabilities in identifying Data Quality Issues (DQIs), we aim to support transparent evaluation and future research by publishing (1) a prototype of the Case-Based Reasoning (CBR) system and (2) a publicly accessible, meticulously annotated sensor-log benchmark. Together, these resources provide a reproducible baseline and a modular foundation for advancing similarity metrics, expanding the DQI taxonomy, and enabling knowledge-intensive reasoning in IoT data quality management.},
keywords = {Data Quality Issues, Industrial Internet of Things, Temporal Case-Based Reasoning, Time Series Data},
pubstate = {published},
tppubtype = {article}
}
Smart manufacturing applications increasingly rely on time-series data from Industrial IoT sensors, yet these data streams often contain data quality issues (DQIs) that affect analysis and disrupt production. While traditional Machine Learning methods are difficult to apply due to the small amount of data available, the knowledge-based approach of Case-Based Reasoning (CBR) offers a way to reuse previously gained experience. We introduce the first end-to-end Case-Based Reasoning (CBR) framework that both detects and remedies DQIs in near real time, even when only a handful of annotated fault instances are available. Our solution encodes expert experience in the four CBR knowledge containers: (i) a vocabulary that represents sensor streams and their context in the DataStream format; (ii) a case base populated with fault-annotated event logs; (iii) tailored similarity measures—including a weighted Dynamic Time Warping variant and structure-aware list mapping—that isolate the signatures of missing-value, missing-sensor, and time-shift errors; and (iv) lightweight adaptation rules that recommend concrete repair actions or, where appropriate, invoke automated imputation and alignment routines. A case study is used to examine and present the suitability of the approach for a specific application domain. Although the case study demonstrates only limited capabilities in identifying Data Quality Issues (DQIs), we aim to support transparent evaluation and future research by publishing (1) a prototype of the Case-Based Reasoning (CBR) system and (2) a publicly accessible, meticulously annotated sensor-log benchmark. Together, these resources provide a reproducible baseline and a modular foundation for advancing similarity metrics, expanding the DQI taxonomy, and enabling knowledge-intensive reasoning in IoT data quality management.
Seiger, Ronny; Schultheis, Alexander; Bergmann, Ralph
Case-Based Activity Detection from Segmented Internet of Things Data Proceedings Article
In: Case-Based Reasoning Research and Development - 33rd International Conference, ICCBR 2025, Biarritz, France, June 30 - July 3rd, 2025, Proceedings, pp. 438–453, Springer., 2025, (Accepted for Publication.).
Abstract | Links | BibTeX | Tags: Activity Detection, Internet of Things, Temporal Case-Based Reasoning, Time Series Data
@inproceedings{SeigerSB2025,
title = {Case-Based Activity Detection from Segmented Internet of Things Data},
author = {Ronny Seiger and Alexander Schultheis and Ralph Bergmann},
url = {https://www.wi2.uni-trier.de/shared/publications/2025_ICCBR_SeigerEtAL.pdf},
doi = {10.1007/978-3-031-96559-3_29},
year = {2025},
date = {2025-01-01},
booktitle = {Case-Based Reasoning Research and Development - 33rd International Conference, ICCBR 2025, Biarritz, France, June 30 - July 3rd, 2025, Proceedings},
pages = {438–453},
publisher = {Springer.},
series = {Lecture Notes in Computer Science},
abstract = {The use of Internet of Things (IoT) technologies drives the automation of business processes. However, such environments often lack process awareness and corresponding systems to monitor process executions. Due to its too fine-grained nature and variations, the direct use of data from IoT devices for monitoring is problematic, requiring an event abstraction step to lift the data to the business process level. This work investigates the application of Temporal Case-Based Reasoning (TCBR) as a novel experience-based approach to detect process activity executions in IoT data. The proposed TCBR approach uses activity signatures - representations of process and IoT data for an activity prototype - as a case base to classify unknown IoT time series data from a smart factory. A data flow architecture is presented that supports analysts in selecting a suitable activity prototype and evaluating its quality for activity detection. The results enable both, the development of high-quality activity detection services and the identification of improvement opportunities in IoT monitoring systems. The approach is evaluated using data produced by a smart factory. The results indicate that the TCBR methods used are very suitable for detecting activities in this IoT use case.},
note = {Accepted for Publication.},
keywords = {Activity Detection, Internet of Things, Temporal Case-Based Reasoning, Time Series Data},
pubstate = {published},
tppubtype = {inproceedings}
}
The use of Internet of Things (IoT) technologies drives the automation of business processes. However, such environments often lack process awareness and corresponding systems to monitor process executions. Due to its too fine-grained nature and variations, the direct use of data from IoT devices for monitoring is problematic, requiring an event abstraction step to lift the data to the business process level. This work investigates the application of Temporal Case-Based Reasoning (TCBR) as a novel experience-based approach to detect process activity executions in IoT data. The proposed TCBR approach uses activity signatures - representations of process and IoT data for an activity prototype - as a case base to classify unknown IoT time series data from a smart factory. A data flow architecture is presented that supports analysts in selecting a suitable activity prototype and evaluating its quality for activity detection. The results enable both, the development of high-quality activity detection services and the identification of improvement opportunities in IoT monitoring systems. The approach is evaluated using data produced by a smart factory. The results indicate that the TCBR methods used are very suitable for detecting activities in this IoT use case.
Weich, Justin; Schultheis, Alexander; Hoffmann, Maximilian; Bergmann, Ralph
Integration of Time Series Embedding for Efficient Retrieval in Case-Based Reasoning Proceedings Article
In: Case-Based Reasoning Research and Development - 33rd International Conference, ICCBR 2025, Biarritz, France, June 30 - July 3rd, 2025, Proceedings, pp. 328–344, Springer., 2025, (Accepted for Publication.).
Abstract | Links | BibTeX | Tags: Siamese Neural Networks, Temporal Case-Based Reasoning, Time Series Data, Time Series Embedding, Time Series Similarity Measure
@inproceedings{WeichSHB2025,
title = {Integration of Time Series Embedding for Efficient Retrieval in Case-Based Reasoning},
author = {Justin Weich and Alexander Schultheis and Maximilian Hoffmann and Ralph Bergmann},
url = {https://www.wi2.uni-trier.de/shared/publications/2025_ICCBR_WeichEtAL.pdf},
doi = {10.1007/978-3-031-96559-3_22},
year = {2025},
date = {2025-01-01},
booktitle = {Case-Based Reasoning Research and Development - 33rd International Conference, ICCBR 2025, Biarritz, France, June 30 - July 3rd, 2025, Proceedings},
pages = {328–344},
publisher = {Springer.},
series = {Lecture Notes in Computer Science},
abstract = {The increasing volume of time series data in Industry 4.0 applications creates substantial challenges for real-time data analysis. Such analyses that are conducted in the research area of Temporal Case-Based Reasoning (TCBR) face performance problems due to complex similarity measures. One potential approach already proven in other domains for addressing these problems is the usage of embedding techniques for time series data, which map these data into a simplified vector representation. Therefore, this paper investigates the integration of time series embedding techniques in the context of Case-Based Reasoning (CBR) to improve retrieval efficiency. Therefore, requirements for the application of embedding techniques in CBR are derived. A systematic literature study identifies possible approaches that are analyzed based on the requirements, with the result that no approach is suitable for the application. Therefore, a novel embedding architecture is proposed, using a Siamese neural network approach that can be trained with similarity values. The architecture is prototypically implemented in the ProCAKE framework and evaluated in an Internet of Things use case from a smart factory. The results demonstrate that the embedding-based retrieval achieves classification performance comparable to traditional similarity measures while significantly reducing retrieval time.},
note = {Accepted for Publication.},
keywords = {Siamese Neural Networks, Temporal Case-Based Reasoning, Time Series Data, Time Series Embedding, Time Series Similarity Measure},
pubstate = {published},
tppubtype = {inproceedings}
}
The increasing volume of time series data in Industry 4.0 applications creates substantial challenges for real-time data analysis. Such analyses that are conducted in the research area of Temporal Case-Based Reasoning (TCBR) face performance problems due to complex similarity measures. One potential approach already proven in other domains for addressing these problems is the usage of embedding techniques for time series data, which map these data into a simplified vector representation. Therefore, this paper investigates the integration of time series embedding techniques in the context of Case-Based Reasoning (CBR) to improve retrieval efficiency. Therefore, requirements for the application of embedding techniques in CBR are derived. A systematic literature study identifies possible approaches that are analyzed based on the requirements, with the result that no approach is suitable for the application. Therefore, a novel embedding architecture is proposed, using a Siamese neural network approach that can be trained with similarity values. The architecture is prototypically implemented in the ProCAKE framework and evaluated in an Internet of Things use case from a smart factory. The results demonstrate that the embedding-based retrieval achieves classification performance comparable to traditional similarity measures while significantly reducing retrieval time.
2023
Malburg, Lukas; Schultheis, Alexander; Bergmann, Ralph
Modeling and Using Complex IoT Time Series Data in Case-Based Reasoning: From Application Scenarios to Implementations Proceedings Article
In: Malburg, Lukas; Verma, Deepika (Ed.): Proceedings of the Workshops at the 31st International Conference on Case-Based Reasoning (ICCBR-WS 2023) co-located with the 31st International Conference on Case-Based Reasoning (ICCBR 2023), Aberdeen, Scotland, UK, July 17, 2023, pp. 81–96, CEUR-WS.org, 2023.
Abstract | Links | BibTeX | Tags: {Case-Based Reasoning, Internet of Things, ProCAKE}, Temporal Case-Based Reasoning, Time Series Data
@inproceedings{Malburg.2023_TimeSeriesInCBR,
title = {Modeling and Using Complex IoT Time Series Data in Case-Based Reasoning:
From Application Scenarios to Implementations},
author = {Lukas Malburg and Alexander Schultheis and Ralph Bergmann},
editor = {Lukas Malburg and Deepika Verma},
url = {http://www.wi2.uni-trier.de/shared/publications/2023_Malburg_TimeSeriesInCBR.pdf},
year = {2023},
date = {2023-01-01},
booktitle = {Proceedings of the Workshops at the 31st International Conference
on Case-Based Reasoning (ICCBR-WS 2023) co-located with the 31st
International Conference on Case-Based Reasoning (ICCBR 2023), Aberdeen,
Scotland, UK, July 17, 2023},
volume = {3438},
pages = {81–96},
publisher = {CEUR-WS.org},
series = {CEUR Workshop Proceedings},
abstract = {The research area of Internet of Things (IoT) is gaining more relevance for several domains and application areas, including Case-Based Reasoning (CBR). However, IoT data is characterized by high volumes and variance of data types, making the application of CBR methods difficult. Since only few works have been published in this area so far, the integration and consideration of complex IoT data such as time series data in CBR frameworks is still in its infancy. To catch up with the current state-of-the-art, we present a comprehensive literature review on Temporal Case-Based Reasoning and time series data in CBR as part of our contribution. Furthermore, we present typical application scenarios for using IoT time series data in practice that can be addressed in further research. To build suitable CBR implementations for that purpose, we define a procedure model that can be used for time series data in CBR. In this context, we address the implementation of the application scenarios in the ProCAKE CBR framework.},
keywords = {{Case-Based Reasoning, Internet of Things, ProCAKE}, Temporal Case-Based Reasoning, Time Series Data},
pubstate = {published},
tppubtype = {inproceedings}
}
The research area of Internet of Things (IoT) is gaining more relevance for several domains and application areas, including Case-Based Reasoning (CBR). However, IoT data is characterized by high volumes and variance of data types, making the application of CBR methods difficult. Since only few works have been published in this area so far, the integration and consideration of complex IoT data such as time series data in CBR frameworks is still in its infancy. To catch up with the current state-of-the-art, we present a comprehensive literature review on Temporal Case-Based Reasoning and time series data in CBR as part of our contribution. Furthermore, we present typical application scenarios for using IoT time series data in practice that can be addressed in further research. To build suitable CBR implementations for that purpose, we define a procedure model that can be used for time series data in CBR. In this context, we address the implementation of the application scenarios in the ProCAKE CBR framework.