The logistics industry is one of the most important industries, being an important component of a company's activities. In recent years, the industry has gone through a large number of changes. These had the purpose of making the processes more efficient in order to reduce costs or to increase the degree of competitiveness. A very important process in the logistics industry is the allocation of roles in warehouses. Not using the available resources to their maximum capacity leads to an increase in the processing time of the units as well as to a decrease in the profitability of the companies. Allocation is done manually in the warehouse, being a complex task in which many constraints and variations must be taken into account. AI technologies and IoT systems have the potential to simplify the process of assigning workers. For this research, a warehouse in Germany operated by the Amazon company was studied. In addition to the benefits that this transition can have from a social point of view, helping to equalize the roles of high complexity and the appropriate rotation of jobs to ensure equal opportunities for development, there is an opportunity to reduce the costs associated with this process by up to 90%. This last aspect is dependent on the degree of modernization of the warehouse and on the way in which the role allocation process is carried out at the time. Most of the IoT systems necessary for the digitization and automation of this process are already implemented in warehouses. However, a common architecture is needed to be able to guarantee the integration and compatibility of the systems. The main blocker in this transition remains public opinion and financial factors, companies with a large volume of units potentially benefiting from economies of scale. / Logistikbranschen är en av de viktigaste branscherna och är en viktig del av ett företags verksamhet. De senaste åren har branschen genomgått ett stort antal förändringar. Dessa hade till syfte att effektivisera processerna för att minska kostnaderna eller öka graden av konkurrenskraft. En mycket viktig process inom logistikbranschen är fördelningen av roller i lager. Att inte använda de tillgängliga resurserna till sin maximala kapacitet leder till en ökad handläggningstid för enheterna samt till en minskad lönsamhet för företagen. Allokering sker manuellt i lagret, vilket är en komplex uppgift där många begränsningar och variationer måste beaktas. AI-teknik och IoT-system har potential att förenkla processen för att tilldela arbetare. För denna forskning studerades ett lager i Tyskland som drivs av Amazon-företaget. Förutom de fördelar som denna övergång kan ha ur en social synvinkel, hjälpa till att utjämna rollerna med hög komplexitet och lämplig rotation av jobb för att säkerställa lika möjligheter till utveckling, finns det en möjlighet att minska kostnaderna förknippade med denna process med upp till 90 %. Den sista aspekten är beroende av graden av modernisering av lagret och på det sätt på vilket rollfördelning processen går till vid tillfället. De flesta av de IoT-system som krävs för digitalisering och automatisering av denna process är redan implementerade i lager. Det behövs dock en gemensam arkitektur för att kunna garantera systemets integration och kompatibilitet. Den huvudsakliga blockeraren i denna övergång är fortfarande den allmänna opinionen och finansiella faktorer, företag med en stor volym av enheter som potentiellt kan dra nytta av stordriftsfördelar.

This dissertation aims to provide efficient process defect identification methods for advanced manufacturing environments using AI tools/algorithms with limited labeled data availability. Asset and equipment quality become highly sensitive in sustaining virtuous performance and safety in various manufacturing domains. Internally generated process imperfections degrade finished products' optimum performance and mechanical attributes. The evolution of big data and intelligent sensing systems leverage data-driven defect identification in advanced manufacturing environments. Widely adopted data-driven process anomaly detection methods assume that the training (source) and testing (target) data follow the same distribution and that labeled data are available in both source and target domains. However, the source and target sometimes follow different distributions in real-world manufacturing environments as the diversity of industrialization processes leads to heterogeneous data collection under different production conditions. Such a case significantly limits the performance of AI algorithms when distribution discrepancy exists. Moreover, labeling data is typically costly and time-consuming, signifying that identifying process defects is limited by rare labeled data. Also, more realistic industrial applications incorporate fewer defect data than ordinal data and unforeseen target defects, leading to complications in understanding the process behaviors in various aspects. Therefore, we introduced methodological principles, including unsupervised grouping, transfer learning, data augmentation, and ensemble learning to address these limitations in advanced operations. First, rapid porosity prediction methodology for additive manufacturing (AM) processes under varying process conditions is developed by leveraging knowledge transfer from existing process conditions. Second, designing an effective classification method concerning time series signals to advance predictive maintenance (PdM) for machine state prediction is discussed. Finally, a data augmentation-based stacking classifier approach is developed to enhance the precision of predicting porosity, even when limited porosity data is available.

Machine learning methods have been used very successfully for quite some time to recognize patterns, model correlations and generate hypotheses. However, the possibilities for weighing and evaluating the resulting models and hypotheses, and the search for alternatives and contradictions are still predominantly reserved for humans. For this purpose, the novel concept of constructivist machine learning (conML) formalizes limitations of model validity and employs constructivist learning theory to enable doubting of new and existing models with the possibility of integrating, discarding, combining, and abstracting knowledge. The present work identifies issues that impede the systems capability to abstract knowledge from generated models for tasks that lie in the domain of procedural knowledge, and proposes and implements identified solutions. To this end, the conML framework has been reimplemented in the Julia programming language and subsequently been extended. Using a synthetic dataset of impedance spectra of modeled epithelia that has previously been analyzed with an existing implementation of conML, existing and new implementations are tested for consistency and proposed algorithmic changes are evaluated with respect to changes in model generation and abstraction ability when exploring unknown data. Recommendations for specific settings and suggestions for further research are derived from the results. In terms of performance, flexibility and extensibility, the new implementation of conML in Julia provides a good starting point for further research and application of the system.:Contents Abstract . . . . . III Zusammenfassung . . . . . IV Danksagung . . . . . V Selbstständigkeitserklärung . . . . . V 1. Introduction 1.1. Research Questions . . . . . 2 2. Related Work 2.1. Hybrid AI Systems . . . . . 5 2.2. Constructivist Machine Learning (conML) . . . . . 6 2.3. Implemented Methods . . . . . 9 2.3.1. Unsupervised Machine Learning . . . . . 9 2.3.2. Supervised Machine Learning . . . . . 11 2.3.3. Supervised Feature Selection . . . . . 13 2.3.4. Unsupervised Feature Selection . . . . . 17 3. Methods and Implementation 3.1. Notable Algorithmic Changes . . . . . 19 3.1.1. Rescaling of Target Values . . . . . 19 3.1.2. ExtendedWinner Selection . . . . . 21 3.2. Package Structure . . . . . 23 3.3. Interfaces and Implementation of Specific Methods . . . . . 29 3.4. Datasets . . . . . 41 4. Results 4.1. Validation Against the conML Prototype . . . . . 43 4.2. Change in Abstraction Capability . . . . . 49 4.2.1. Influence of Target Scaling . . . . . 49 4.2.2. Influence of the Parameter kappa_p . . . . . 55 4.2.3. Influence of the Winner Selection Procedure . . . . . 61 5. Discussion 5.1. Reproduction Results . . . . . 67 5.2. Rescaling of Constructed Targets . . . . . 69 5.3. kappa_p and the Selection of Winner Models . . . . . 71 6. Conclusions 6.1. Contributions of this Work . . . . . 77 6.2. Future Work . . . . . 78 A. Julia Language Reference . . . . . 81 B. Additional Code Listings . . . . . 91 C. Available Parameters . . . . . 99 C.1. Block Processing . . . . . 105 D. Configurations Reference . . . . . 107 D.1. Unsupervised Methods . . . . . 107 D.2. Supervised Methods . . . . . 108 D.3. Feature Selection . . . . . 109 D.4. Winner Selection . . . . . 110 D.5. General Settings . . . . . 110 E. Supplemental Figures . . . . . 113 E.1. Replacing MAPE with RMSE for Z-Transform Target Scaling . . . . . 113 E.2. Combining Target Rescaling, Winner Selection and High kappa_p . . . . . 119 Bibliography . . . . . 123 List of Figures . . . . . 129 List of Listings . . . . . 133 List of Tables . . . . . 135 / Maschinelle Lernverfahren werden seit geraumer Zeit sehr erfolgreich zum Erkennen von Mustern, Abbilden von Zusammenhängen und Generieren von Hypothesen eingesetzt. Die Möglichkeiten zum Abwägen und Bewerten der entstandenen Modelle und Hypothesen, und die Suche nach Alternativen und Widersprüchen sind jedoch noch überwiegend dem Menschen vorbehalten. Das neuartige Konzept des konstruktivistischen maschinellen Lernens (conML) formalisiert dazu die Grenzen der Gültigkeit von Modellen und ermöglicht mittels konstruktivistischer Lerntheorie ein Zweifeln über neue und bestehende Modelle mit der Möglichkeit zum Integrieren, Verwerfen, Kombinieren und Abstrahieren von Wissen. Die vorliegende Arbeit identifiziert Probleme, die die Abstraktionsfähigkeit des Systems bei Aufgabenstellungen in der Prozeduralen Wissensdomäne einschränken, bietet Lösungsvorschläge und beschreibt deren Umsetzung. Das algorithmische Framework conML ist dazu in der Programmiersprache Julia reimplementiert und anschließend erweitert worden. Anhand eines synthetischen Datensatzes von Impedanzspektren modellierter Epithelien, der bereits mit einem Prototypen des conML Systems analysiert worden ist, werden bestehende und neue Implementierung auf Konsistenz geprüft und die vorgeschlagenen algorithmischen Änderungen im Hinblick auf Veränderungen beim Erzeugen von Modellen und der Abstraktionsfähigkeit bei der Exploration unbekannter Daten untersucht. Aus den Ergebnissen werden Empfehlungen zu konkreten Einstellungen sowie Vorschläge für weitere Untersuchungen abgeleitet. Die neue Implementierung von conML in Julia bietet im Hinblick auf Performanz, Flexibilität und Erweiterbarkeit einen guten Ausgangspunkt für weitere Forschung und Anwendung des Systems.:Contents Abstract . . . . . III Zusammenfassung . . . . . IV Danksagung . . . . . V Selbstständigkeitserklärung . . . . . V 1. Introduction 1.1. Research Questions . . . . . 2 2. Related Work 2.1. Hybrid AI Systems . . . . . 5 2.2. Constructivist Machine Learning (conML) . . . . . 6 2.3. Implemented Methods . . . . . 9 2.3.1. Unsupervised Machine Learning . . . . . 9 2.3.2. Supervised Machine Learning . . . . . 11 2.3.3. Supervised Feature Selection . . . . . 13 2.3.4. Unsupervised Feature Selection . . . . . 17 3. Methods and Implementation 3.1. Notable Algorithmic Changes . . . . . 19 3.1.1. Rescaling of Target Values . . . . . 19 3.1.2. ExtendedWinner Selection . . . . . 21 3.2. Package Structure . . . . . 23 3.3. Interfaces and Implementation of Specific Methods . . . . . 29 3.4. Datasets . . . . . 41 4. Results 4.1. Validation Against the conML Prototype . . . . . 43 4.2. Change in Abstraction Capability . . . . . 49 4.2.1. Influence of Target Scaling . . . . . 49 4.2.2. Influence of the Parameter kappa_p . . . . . 55 4.2.3. Influence of the Winner Selection Procedure . . . . . 61 5. Discussion 5.1. Reproduction Results . . . . . 67 5.2. Rescaling of Constructed Targets . . . . . 69 5.3. kappa_p and the Selection of Winner Models . . . . . 71 6. Conclusions 6.1. Contributions of this Work . . . . . 77 6.2. Future Work . . . . . 78 A. Julia Language Reference . . . . . 81 B. Additional Code Listings . . . . . 91 C. Available Parameters . . . . . 99 C.1. Block Processing . . . . . 105 D. Configurations Reference . . . . . 107 D.1. Unsupervised Methods . . . . . 107 D.2. Supervised Methods . . . . . 108 D.3. Feature Selection . . . . . 109 D.4. Winner Selection . . . . . 110 D.5. General Settings . . . . . 110 E. Supplemental Figures . . . . . 113 E.1. Replacing MAPE with RMSE for Z-Transform Target Scaling . . . . . 113 E.2. Combining Target Rescaling, Winner Selection and High kappa_p . . . . . 119 Bibliography . . . . . 123 List of Figures . . . . . 129 List of Listings . . . . . 133 List of Tables . . . . . 135