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Künstliche Intelligenz gilt immer noch als eine der zukunftsweisenden Technologien, die viele Bereiche wie etwa Medizin, Handel, Verkehr und öffentliche Verwaltung revolutioniert. So scheint es nicht verwunderlich, dass bereits knapp jedes fünfte Unternehmen in Deutschland zurzeit KI-Systeme implementiert oder zumindest ihren Einsatz plant. Besonders hoch im Kurs stehen KI-Projekte, um Daten zu analysieren. Ganze 70 Prozent der Unternehmen sehen hier das größte Potenzial, so die Ergebnisse einer Umfrage von PWC [1]. Dennoch lauern einige Stolpersteine, wollen Unternehmen intelligente Datenprojekte umsetzen. Welche Hürden auftauchen können und wie sich diese meistern lassen, erläutert dieser Artikel anhand eines KI-Projektes zur Analyse von Geschäftspartnerdaten [2].
The last decades have seen the evolution of industrial production into more sophisticated processes. The development of specialized, high-end machines has increased the importance of predictive maintenance of mechanical systems to produce high-quality goods and avoid machine breakdowns. Predictive maintenance has two main objectives: to classify the current status of a machine component and to predict the maintenance interval by estimating its remaining useful life (RUL). Nowadays, both objectives are covered by machine learning and deep learning approaches and require large training datasets that are often not available. One possible solution may be transfer learning, where the knowledge of a larger dataset is transferred to a smaller one. This thesis is primarily concerned with transfer learning for predictive maintenance for fault classification and RUL estimation. The first part presents the state-of-the-art machine learning techniques with a focus on techniques applicable to predictive maintenance tasks (Chapter 2). This is followed by a presentation of the machine tool background and current research that applies the previously explained machine learning techniques to predictive maintenance tasks (Chapter 3). One novelty of this thesis is that it introduces a new intermediate domain that represents data by focusing on the relevant information to allow the data to be used on different domains without losing relevant information (Chapter 4). The proposed solution is optimized for rotating elements. Therefore, the presented intermediate domain creates different layers by focusing on the fault frequencies of the rotating elements. Another novelty of this thesis is its semi and unsupervised transfer learning-based fault classification approach for different component types under different process conditions (Chapter 5). It is based on the intermediate domain utilized by a convolutional neural network (CNN). In addition, a novel unsupervised transfer learning loss function is presented based on the maximum mean discrepancy (MMD), one of the state-of-the-art algorithms. It extends the MMD by considering the intermediate domain layers; therefore, it is called layered maximum mean discrepancy (LMMD). Another novelty is an RUL estimation transfer learning approach for different component types based on the data of accelerometers with low sampling rates (Chapter 6). It applies the feature extraction concepts of the classification approach: the presented intermediate domain and the convolutional layers. The features are then used as input for a long short-term memory (LSTM) network. The transfer learning is based on fixed feature extraction, where the trained convolutional layers are taken over. Only the LSTM network has to be trained again. The intermediate domain supports this transfer learning type, as it should be similar for different component types. In addition, it enables the practical usage of accelerometers with low sampling rates during transfer learning, which is an absolute novelty. All presented novelties are validated in detailed case studies using the example of bearings (Chapter 7). In doing so, their superiority over state-of-the-art approaches is demonstrated.
Künstliche Intelligenz (KI) kommt laut einer Interxion-Studie bei 96 Prozent der Schweizer Unternehmen zum Einsatz. Allerdings gaben nur 22 Prozent der Schweizer IT-Entscheider an, dass sie KI bereits für einen ersten Anwendungsfall einsetzen. Dabei ist KI etwa im Datenmanagement sehr hilfreich – sofern Qualität und Quantität der Trainingsdaten stimmen.
Prediction of Claims in Export Credit Finance: A Comparison of Four Machine Learning Techniques
(2020)
This study evaluates four machine learning (ML) techniques (Decision Trees (DT), Random Forests (RF), Neural Networks (NN) and Probabilistic Neural Networks (PNN)) on their ability to accurately predict export credit insurance claims. Additionally, we compare the performance of the ML techniques against a simple benchmark (BM) heuristic. The analysis is based on the utilisation of a dataset provided by the Berne Union, which is the most comprehensive collection of export credit insurance data and has been used in only two scientific studies so far. All ML techniques performed relatively well in predicting whether or not claims would be incurred, and, with limitations, in predicting the order of magnitude of the claims. No satisfactory results were achieved predicting actual claim ratios. RF performed significantly better than DT, NN and PNN against all prediction tasks, and most reliably carried their validation performance forward to test performance.
Das Verstehen und Extrahieren von Informationen aus Dokumenten stellt eine Herausforderung dar, welche den Einsatz weiterer Technologien bedarf. Vorliegende
Masterarbeit untersucht die Anwendbarkeit von Methoden des maschinellen Lernens im Bereich der Wissensextraktion auf Basis von Angebotsdokumenten. Hierbei gilt die Frage zu klären, inwiefern sich diese Dokumente eignen, um Strukturen
für die Modellierung mit einem Produktkonfigurator zu lernen. Kern der Arbeit stellen die Datenaufbereitung von PDF-Dokumenten sowie das Modeling multimodal
lernender Algorithmen dar. Abgesehen von Texten werden zusätzlich Layoutinformationen für das Lernen der Strukturen genutzt. Zudem werden die Ergebnisse der
erstellten Modelle evaluiert und die Güte in Anbetracht des vorliegenden Problems
bewertet.
Mit der prototypischen Implementierung einer automatisierten Dokumentengenerierung wird demonstriert, wie das extrahierte Wissen in der Software CAS Configurator Merlin genutzt werden kann.
Maschinelles Lernen verändert zusehends die Arbeitswelt. Auch in der Produktionsplanung und -steuerung finden sich vielversprechende Anwendungsfälle. In diesem Beitrag sollen ausgewählte Anwendungsbereiche und Ansätze vorgestellt werden, die anhand einer umfangreichen Untersuchung wissenschaftlicher Veröffentlichungen identifiziert wurden. Als Strukturierungshilfe dient das Aachener PPS-Modell.
Much of the research in the field of audio-based machine learning has focused on recreating human speech via feature extraction and imitation, known as deepfakes. The current state of affairs has prompted a look into other areas, such as the recognition of recording devices, and potentially speakers, by only analysing sound files. Segregation and feature extraction are at the core of this approach.
This research focuses on determining whether a recorded sound can reveal the recording device with which it was captured. Each specific microphone manufacturer and model, among other characteristics and imperfections, can have subtle but compounding effects on the results, whether it be differences in noise, or the recording tempo and sensitivity of the microphone while recording. By studying these slight perturbations, it was found to be possible to distinguish between microphones based on the sounds they recorded.
After the recording, pre-processing, and feature extraction phases we completed, the prepared data was fed into several different machine learning algorithms, with results ranging from 70% to 100% accuracy, showing Multi-Layer Perceptron and Logistic Regression to be the most effective for this type of task.
This was further extended to be able to tell the difference between two microphones of the same make and model. Achieving the identification of identical models of a microphone suggests that the small deviations in their manufacturing process are enough of a factor to uniquely distinguish them and potentially target individuals using them. This however does not take into account any form of compression applied to the sound files, as that may alter or degrade some or most of the distinguishing features that are necessary for this experiment.
Building on top of prior research in the area, such as by Das et al. in in which different acoustic features were explored and assessed on their ability to be used to uniquely fingerprint smartphones, more concrete results along with the methodology by which they were achieved are published in this project’s publicly accessible code repository.
Die Mehrheit der deutschen Unternehmen verspricht sich aus KI-gestützter Datenanalyse einen großen Geschäftsvorteil. Doch gerade das Thema Datenbestand ist eine der größten, immer noch häufig unterschätzten Hürde beim Trainieren und Einführen von KI-Algorithmen. Im Folgenden sind vier konkrete Erfahrungen und Tipps für KI- & Datenanalyseprojekte in Unternehmen aufgeführt.