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Hönel, S., Picha, P., Ericsson, M., Brada, P., Löwe, W. & Wingkvist, A. (2024). Activity-Based Detection of (Anti-)Patterns: An Embedded Case Study of the Fire Drill. e-Informatica Software Engineering Journal, 18(1), Article ID 240106.
Open this publication in new window or tab >>Activity-Based Detection of (Anti-)Patterns: An Embedded Case Study of the Fire Drill
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2024 (English)In: e-Informatica Software Engineering Journal, ISSN 1897-7979, E-ISSN 2084-4840, Vol. 18, no 1, article id 240106Article in journal (Refereed) Published
Abstract [en]

Background: Nowadays, expensive, error-prone, expert-based evaluations are needed to identify and assess software process anti-patterns. Process artifacts cannot be automatically used to quantitatively analyze and train prediction models without exact ground truth. Aim: Develop a replicable methodology for organizational learning from process (anti-)patterns, demonstrating the mining of reliable ground truth and exploitation of process artifacts. Method: We conduct an embedded case study to find manifestations of the Fire Drill anti-pattern in n = 15 projects. To ensure quality, three human experts agree. Their evaluation and the process’ artifacts are utilized to establish a quantitative understanding and train a prediction model. Results: Qualitative review shows many project issues. (i) Expert assessments consistently provide credible ground truth. (ii) Fire Drill phenomenological descriptions match project activity time (for example, development). (iii) Regression models trained on ≈ 12–25 examples are sufficiently stable. Conclusion: The approach is data source-independent (source code or issue-tracking). It allows leveraging process artifacts for establishing additional phenomenon knowledge and training robust predictive models. The results indicate the aptness of the methodology for the identification of the Fire Drill and similar anti-pattern instances modeled using activities. Such identification could be used in post mortem process analysis supporting organizational learning for improving processes.

Place, publisher, year, edition, pages
Wroclaw University of Science and Technology, 2024
Keywords
anti-patterns, Fire-Drill Case-study
National Category
Software Engineering Computer Sciences
Research subject
Computer Science, Software Technology
Identifiers
urn:nbn:se:lnu:diva-128700 (URN)10.37190/e-inf240106 (DOI)2-s2.0-85188276370 (Scopus ID)
Available from: 2024-04-09 Created: 2024-04-09 Last updated: 2024-10-22Bibliographically approved
Björnberg, D., Ericsson, M., Lindeberg, J., Löwe, W. & Nordqvist, J. (2024). Image generation of log ends and patches of log ends with controlled properties using generative adversarial networks. Signal, Image and Video Processing, 18, 6481-6489
Open this publication in new window or tab >>Image generation of log ends and patches of log ends with controlled properties using generative adversarial networks
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2024 (English)In: Signal, Image and Video Processing, ISSN 1863-1703, E-ISSN 1863-1711, Vol. 18, p. 6481-6489Article in journal (Refereed) Published
Abstract [en]

The appearance of the log cross-section provides important information when assessing the quality of the log, where properties to consider include pith location and density of annual rings. This makes tasks like estimation of pith location and annual ring detection of great interest. However, creating labeled training data for these tasks can be time-consuming and subject to misjudgments. For this reason, we aim to create generated training data with controlled properties of pith location and amount of annual rings. We propose a two-step generator based on generative adversarial networks in which we can completely avoid manual labeling, not only when generating training data but also during training of the generator itself. This opens up the possibility to train the generator on other types of log end data without the need to manually label new training data. The same method is used to create two generated training datasets; one of entire log ends and one of patches of log ends. To evaluate how the generated data compares to real data, we train two deep learning models to perform estimation of pith location and ring counting, respectively. The models are trained separately on real and generated data and evaluated on real data only. The results show that the performance of both estimation of pith location and ring counting can be improved by replacing real training data with larger sets of generated training data.

Place, publisher, year, edition, pages
Springer, 2024
Keywords
Generative adversarial network, Image generation of log ends, Training data generation, Conditional GAN, CycleGAN
National Category
Computer Engineering Computer Sciences Computer Vision and Robotics (Autonomous Systems)
Research subject
Computer and Information Sciences Computer Science, Computer Science
Identifiers
urn:nbn:se:lnu:diva-131577 (URN)10.1007/s11760-024-03331-w (DOI)001249395800002 ()2-s2.0-85196276821 (Scopus ID)
Funder
Knowledge Foundation, 20190336
Available from: 2024-07-31 Created: 2024-07-31 Last updated: 2024-08-29Bibliographically approved
Gundermann, N., Löwe, W., Fransson, J., Olofsson, E. & Wehrenpfennig, A. (2024). Object Identification in Land Parcels Using a Machine Learning Approach. Remote Sensing, 16(7), Article ID 1143.
Open this publication in new window or tab >>Object Identification in Land Parcels Using a Machine Learning Approach
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2024 (English)In: Remote Sensing, E-ISSN 2072-4292, Vol. 16, no 7, article id 1143Article in journal (Refereed) Published
Abstract [en]

This paper introduces an AI-based approach to detect human-made objects and changes in these on land parcels. To this end, we used binary image classification performed by a convolutional neural network. Binary classification requires the selection of a decision boundary, and we provided a deterministic method for this selection. Furthermore, we varied different parameters to improve the performance of our approach, leading to a true positive rate of 91.3% and a true negative rate of 63.0%. A specific application of our work supports the administration of agricultural land parcels eligible for subsidiaries. As a result of our findings, authorities could reduce the effort involved in the detection of human made changes by approximately 50%.

Place, publisher, year, edition, pages
MDPI, 2024
National Category
Computer and Information Sciences
Research subject
Computer and Information Sciences Computer Science
Identifiers
urn:nbn:se:lnu:diva-128444 (URN)10.3390/rs16071143 (DOI)001200821800001 ()2-s2.0-85190273608 (Scopus ID)
Available from: 2024-03-26 Created: 2024-03-26 Last updated: 2024-10-22Bibliographically approved
Kumar, M., Ekevid, T. & Löwe, W. (2024). Operator model for wheel loader short-cycle loading handling. Automation in Construction, 167, Article ID 105691.
Open this publication in new window or tab >>Operator model for wheel loader short-cycle loading handling
2024 (English)In: Automation in Construction, ISSN 0926-5805, E-ISSN 1872-7891, Vol. 167, article id 105691Article in journal (Refereed) Published
Abstract [en]

The need to virtually analyze the interaction between construction equipment machines and geomaterials is critical. This paper investigates the virtual analysis of force-driven maneuvers of a wheel loader (WL) within a co-simulation framework. This framework has been developed integrating the operators' model of the WL and its interaction with the power source model, i.e., the drive train, the hydraulics, and the material. It includes trajectory prediction using optimal control and control strategies to follow computed trajectories. The results show that the co-simulation model aligns well with measurement data validating the model's accuracy in different types of operators driving. The results are very useful for engineers in product development to improve WL design and controls. The successful validation of the framework also paves the way for future research to enhance the virtual simulation techniques to optimize WL performances with different types of operators.

Place, publisher, year, edition, pages
Elsevier, 2024
Keywords
Operator model, Discrete Element Method (DEM), High Fidelity model, Multi body simulation (MBS), Trajectory prediction
National Category
Vehicle Engineering
Research subject
Technology (byts ev till Engineering), Mechanical Engineering
Identifiers
urn:nbn:se:lnu:diva-132196 (URN)10.1016/j.autcon.2024.105691 (DOI)001312555700001 ()2-s2.0-85202868480 (Scopus ID)
Funder
Knowledge Foundation
Available from: 2024-09-02 Created: 2024-09-02 Last updated: 2024-09-30Bibliographically approved
Björneld, O. & Löwe, W. (2024). Real-world validation of a framework for automated knowledge driven feature engineering inspired by medical domain experts. Informatics in Medicine Unlocked, 49, Article ID 101532.
Open this publication in new window or tab >>Real-world validation of a framework for automated knowledge driven feature engineering inspired by medical domain experts
2024 (English)In: Informatics in Medicine Unlocked, ISSN 2352-9148, Vol. 49, article id 101532Article in journal (Refereed) Published
Abstract [en]

Knowledge discovery from real-world data in health care can be demanding due to unstructured data and low registration quality in electronic health records (EHRs). This requires close collaboration of domain experts and data scientists. To perform the knowledge discovery process more effectively and efficiently, a framework for automatic Knowledge Driven Feature Engineering (aKDFE) has been developed. Central to aKDFE is an automated feature engineering (FE), i.e., an automated construction of new, highly informative variables, referred to as features, from those directly observed and recorded, e.g., in EHRs. The framework learns and aggregates domain knowledge to generate features that are more informative compared to those recorded in EHRs or manually engineered (manual FE) as done in medical research projects today. Manual KDFE is a systematic manual FE process, which improves prediction performance without loss of explainability of the predictions. But the following research questions remained open: (i) is it possible to automate KDFE, (ii) are aKDFE features more informative than features from a manual FE process, and (iii) does aKDFE produce explainable and transparent results? To summarize the present study, aKDFE is (i) more efficient than manual FE since it automates the manual knowledge discovery and FE processes. It is (ii) more effective due to its higher predictive power compared to manual KDFE. This was evaluated on a real-world medical research project by comparing the classification ability when using manual and aKDFE features in machine learning (ML) models, measured as the area under the receiver operating characteristic curve (AUROC). The project included 26,992 patients regarding “Negative bone structure effects of antiepileptic drug consumption”. The baseline features (manual FE) used in studied project were compared with features generated by aKDFE; aKDFE-generated features resulted in higher AUROC than baseline features, with a p-value <0.05. Finally, aKDFE (iii) applies and describes data pivoting and feature generation as explicit and transparent operation sequences on EHR features. Inefficiency issues remain, mainly regarding non-automatic FE and baseline generation.Threat of validity to the aKDFE framework exists in the selection of the pivoting method, the generalization of used FE operations and rules, and usage of evaluation metrics.

Place, publisher, year, edition, pages
Elsevier, 2024
Keywords
Feature engineering (FE), Medical registry research, Automated knowledge discovery in databases (KDD), Electronic health record (EHR), Medical domain knowledge, Iterative FE
National Category
Public Health, Global Health, Social Medicine and Epidemiology Information Systems
Research subject
Computer and Information Sciences Computer Science, Computer Science
Identifiers
urn:nbn:se:lnu:diva-133250 (URN)10.1016/j.imu.2024.101532 (DOI)2-s2.0-85196769944 (Scopus ID)
Available from: 2024-11-07 Created: 2024-11-07 Last updated: 2024-11-11Bibliographically approved
Ghayvat, H., Awais, M., Geddam, R., Tiwari, P. & Löwe, W. (2024). Revolutionizing healthcare: IoMT-enabled digital enhancement via multimodal ADL data fusion. Information Fusion, 111, Article ID 102518.
Open this publication in new window or tab >>Revolutionizing healthcare: IoMT-enabled digital enhancement via multimodal ADL data fusion
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2024 (English)In: Information Fusion, ISSN 1566-2535, E-ISSN 1872-6305, Vol. 111, article id 102518Article in journal (Refereed) Published
Abstract [en]

The present research develops a framework to refine the classification of an individual's activities and recognize wellness associated with their routine. The framework improves the accuracy of the classification of routine activities of a person, the activation time data of sensors fixed on objects linked with the routine activities of the person, and the aptness of an incessant activity pattern with the routine activities. The existing techniques need continuous monitoring and are non-adaptive to a person's persistent habitual variations or individualities. The research involves applying Internet of Medical Things (IoMT)-based sensor information fusion to the novel multimodel data analytics to develop Activities of Daily Living (ADL) pattern, behavioral pattern generation and anomaly recognition. The novel multimodel data analytics approach is named AiCareLiving. AicareLiving is an IoMT and artificial intelligence (AI) enabled approach. The research work describes activity data using an individual's activities within a specified area before evaluating the activity data to detect the existence of an anomaly by identifying the deviation of the activity data from the activity profile, which indicates the anticipated behavior and activity of the person. This wellness information would be shared to the caregivers, related healthcare professionals, care providers and municipalities through the secured healthcare information exchange protocol and IoMT. AiCareLiving framework aims to least false positive in terms of anomaly detection and forecasting; the high precision is close to the confidence level of 95%.

Place, publisher, year, edition, pages
Elsevier, 2024
Keywords
Multi-Sensor Modalities data, Sensor information fusion, IoMT, AIoMT, Behavioral pattern generation, Ambient assisted living, Digitally enhanced, ADL, Information fusion
National Category
Computer Sciences
Research subject
Computer and Information Sciences Computer Science, Computer Science
Identifiers
urn:nbn:se:lnu:diva-131802 (URN)10.1016/j.inffus.2024.102518 (DOI)001266901200001 ()2-s2.0-85196955585 (Scopus ID)
Available from: 2024-08-15 Created: 2024-08-15 Last updated: 2024-09-05Bibliographically approved
Björnberg, D., Ericsson, M., Löwe, W. & Nordqvist, J. (2024). Unpaired Image-to-Image Translation to Improve Log End Identification. In: ESANN 2024 proceedings: . Paper presented at European Symposium on Artificial Neural Networks, Computational Intelligence and Machine Learning (pp. 673-678). i6doc
Open this publication in new window or tab >>Unpaired Image-to-Image Translation to Improve Log End Identification
2024 (English)In: ESANN 2024 proceedings, i6doc , 2024, p. 673-678Conference paper, Published paper (Refereed)
Abstract [en]

Visual re-identification tasks are often subject to large domain variations due to camera types, brightness conditions, or environmental differences. For identification models to generalize in such varying domains, a large amount of training data is necessary for capturing these variations. We explore the potential of using unpaired image-to-image translation to enhance the generalization capacity of a log end identification model in the absence or combined with a smaller amount of labeled training data.

Place, publisher, year, edition, pages
i6doc, 2024
National Category
Computer Vision and Robotics (Autonomous Systems)
Identifiers
urn:nbn:se:lnu:diva-133286 (URN)9782875870902 (ISBN)
Conference
European Symposium on Artificial Neural Networks, Computational Intelligence and Machine Learning
Available from: 2024-11-09 Created: 2024-11-09 Last updated: 2024-11-13Bibliographically approved
Lincke, A., Fagerström, C., Ekstedt, M., Löwe, W. & Backåberg, S. (2023). A comparative study of the 2D- and 3D-based skeleton avatar technology for assessing physical activity and functioning among healthy older adults. Health Informatics Journal, 29(4)
Open this publication in new window or tab >>A comparative study of the 2D- and 3D-based skeleton avatar technology for assessing physical activity and functioning among healthy older adults
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2023 (English)In: Health Informatics Journal, ISSN 1460-4582, E-ISSN 1741-2811, Vol. 29, no 4Article in journal (Refereed) Published
Abstract [en]

Background: Maintaining physical activity (PA) and functioning (mobility, balance) is essential for older adults’ well-being and quality of life. However, current methods (functional tests, self-reports) and available techniques (accelerometers, sensors, advanced movement analysis systems) for assessing physical activity and functioning have shown to be less reliable, time- and resource-consuming with limited routine usage in clinical practice. There is a need to simplify the assessment of physical activity and functioning among older adults both in health care and clinical studies. This work presents a study on using Skeleton Avatar Technology (SAT) for this assessment. SAT analyzes human movement videos using artificial intelligence (AI). The study compares handy SAT based on 2D camera technology (2D SAT) with previously studied 3D SAT for assessing physical activity and functioning in older adults. Objective: To explore whether 2D SAT yields accurate results in physical activity and functioning assessment in healthy older adults, statistically compared to the accuracy of 3D SAT. Method: The mobile pose estimation model provided by Tensorflow was used to extract 2D skeletons from the video recordings of functional test movements. Deep neural networks were used to predict the outcomes of functional tests (FT), expert-based movement quality assessment (EA), accelerometer-based assessments (AC), and self-assessments of PA (SA). To compare the accuracy with 3D SAT models, statistical analysis was used to test whether the difference in the predictions between 2D and 3D models is significant or not. Results: Overall, the accuracy of 2D SAT is lower than 3D SAT in predicting FTs and EA. 2D SAT was able to predict AC with 7% Mean Absolute Error (MAE), and self-assessed PA (SA) with 16% MAE. On average MAE was 4% higher for 2D than for 3D SAT. There was no significant difference found between the 2D and the 3D model for AC and for two FTs (30 seconds chair stand test, 30sCST and Timed up and go, TUG). A significant difference was found for the 2D- and 3D-model of another FT (4-stage balance test, 4SBT). Conclusion: Altogether, the results show that handy 2D SAT might be used for assessing physical activity in older adults without a significant loss of accuracy compared to time-consuming standard tests and to bulky 3D SAT-based assessments. However, the accuracy of 2D SAT in assessing physical functioning should be improved. Taken together, this study shows promising results to use 2D SAT for assessing physical activity in healthy older adults in future clinical studies and clinical practice.

Place, publisher, year, edition, pages
SAGE Open, 2023
Keywords
Physical activity, Skeleton avatar technology, machine learning, older adults, functioning mobility, balance
National Category
Sport and Fitness Sciences Computer Sciences
Research subject
Health and Caring Sciences, Health Informatics
Identifiers
urn:nbn:se:lnu:diva-125488 (URN)10.1177/14604582231214589 (DOI)001095930700001 ()2-s2.0-85176326223 (Scopus ID)
Available from: 2023-11-06 Created: 2023-11-06 Last updated: 2024-10-22Bibliographically approved
Kumar, M., Cramsky, J., Löwe, W. & Danielsson, P.-O. (2023). A prediction model for exhaust gas regeneration(EGR) clogging using offline and online machinelearning. In: Karsten Berns, Klaus Dressler, Ralf Kalmar, Nicole Stephan, Roman Teutsch, Martin Thul (Ed.), Commercial Vehicle Technology 2022: Proceedings of 7th commercial vehicle technology symposium.. Paper presented at International Commercial Vehicle Technology Symposium (pp. 185-198). Wiesbaden: Springer
Open this publication in new window or tab >>A prediction model for exhaust gas regeneration(EGR) clogging using offline and online machinelearning
2023 (English)In: Commercial Vehicle Technology 2022: Proceedings of 7th commercial vehicle technology symposium. / [ed] Karsten Berns, Klaus Dressler, Ralf Kalmar, Nicole Stephan, Roman Teutsch, Martin Thul, Wiesbaden: Springer, 2023, p. 185-198Conference paper, Published paper (Refereed)
Abstract [en]

The exhaust gas regeneration (EGR) also called exhaust gasre-circulation system in an engine of construction machine (CM) oftengets clogged due to various ways of driving the machines. Currently, theredoes not exist any model that can predict clogging for maintenance planning.Hence, clogging is only recognized when it has occurred, and oftencauses the CM to drop out. Engines still operated despite clogging causesfrequent cold engine running, and excessive exhaustion of nitrogen, whichleads to loss of the engine's performance and reduces their lives.We propose an approach that builds on virtual key sensors. Virtual keysensors are usually used to replace real sensors. However, we proposeto compare the virtual and the real sensor outcomes. If di erences betweenthe estimated and the real value emerge, we assume changes ofthe systems because of, e.g., clogging or leakage in pipes. EGR pressureis identi ed as an important sensor to estimate clogging. A virtualsensor of EGR pressure is built from other real sensors based on a polynomialregression model [1]. The error between the real and the virtualEGR pressure sensors varies between 5-10% depending on the driver'sbehaviors. The model discriminates the ideal ways of working and abnormalities.Moreover, we suggest to adapt the weights of the regressionmodel to other engine types of the same engine family based on onlinestochastic gradient descent algorithm. Since the deployed regression andadaptation algorithms are computationally inexpensive, the approachcould be applied using existing CM micro controllers.

Place, publisher, year, edition, pages
Wiesbaden: Springer, 2023
Series
Proceedings, ISSN 2198-7432, E-ISSN 2198-7440 ; 7
Keywords
Polynomial regression, EGR, Predictive Model, Virtual sensor
National Category
Vehicle Engineering Control Engineering
Research subject
Computer and Information Sciences Computer Science, Media Technology; Technology (byts ev till Engineering), Mechanical Engineering
Identifiers
urn:nbn:se:lnu:diva-119668 (URN)10.1007/978-3-658-40783-4_13 (DOI)9783658407827 (ISBN)9783658407834 (ISBN)
Conference
International Commercial Vehicle Technology Symposium
Funder
Knowledge Foundation
Available from: 2023-03-08 Created: 2023-03-08 Last updated: 2023-05-02Bibliographically approved
Lincke, A., Roth, J., Macedo, A. F., Bergman, P., Löwe, W. & Lagali, N. S. (2023). AI-Based Decision-Support System for Diagnosing Acanthamoeba Keratitis Using In Vivo Confocal Microscopy Images. Translational Vision Science & Technology, 12(11), Article ID 29.
Open this publication in new window or tab >>AI-Based Decision-Support System for Diagnosing Acanthamoeba Keratitis Using In Vivo Confocal Microscopy Images
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2023 (English)In: Translational Vision Science & Technology, E-ISSN 2164-2591, Vol. 12, no 11, article id 29Article in journal (Refereed) Published
Abstract [en]

Purpose: In vivo confocal microscopy (IVCM) of the cornea is a valuable tool for clinical assessment of the cornea but does not provide stand-alone diagnostic support. The aim of this work was to develop an artificial intelligence (AI)-based decision-support system (DSS) for automated diagnosis of Acanthamoeba keratitis (AK) using IVCM images.

Methods: The automated workflow for the AI-based DSS was defined and implemented using deep learning models, image processing techniques, rule-based decisions, and valuable input from domain experts. The models were evaluated with 5-fold-cross validation on a dataset of 85 patients (47,734 IVCM images from healthy, AK, and other disease cases) collected at a single eye clinic in Sweden. The developed DSS was validated on an additional 26 patients (21,236 images).

Results: Overall, the DSS uses as input raw unprocessed IVCM image data, successfully separates artefacts from true images (93% accuracy), then classifies the remaining images by their corneal layer (90% accuracy). The DSS subsequently predicts if the cornea is healthy or diseased (95% model accuracy). In disease cases, the DSS detects images with AK signs with 84% accuracy, and further localizes the regions of diagnostic value with 76.5% accuracy.

Conclusions: The proposed AI-based DSS can automatically and accurately preprocess IVCM images (separating artefacts and sorting images into corneal layers) which decreases screening time. The accuracy of AK detection using raw IVCM images must be further explored and improved.

Translational Relevance: The proposed automated DSS for experienced specialists assists in diagnosing AK using IVCM images.

Place, publisher, year, edition, pages
Association for research in vision and ophthalmology (ARVO), 2023
Keywords
image analysis, acanthamoeba keratitis, deep learning, in vivo confocal microscopy images
National Category
Computer Systems Medical Image Processing
Research subject
Computer and Information Sciences Computer Science, Computer Science
Identifiers
urn:nbn:se:lnu:diva-125803 (URN)10.1167/tvst.12.11.29 (DOI)001125044500009 ()2-s2.0-85178009830 (Scopus ID)
Available from: 2023-11-28 Created: 2023-11-28 Last updated: 2024-01-16Bibliographically approved
Organisations
Identifiers
ORCID iD: ORCID iD iconorcid.org/0000-0002-7565-3714

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