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Forensic method for recognizing the authenticity of artworks using multispectral analysis
Lánský, David ; Mezina, Anzhelika (referee) ; Burget, Radim (advisor)
Detecting forgeries is crucial for protecting the art market and preserving the authenticity of artworks. This thesis focuses on forgery detection using convolutional neural networks (CNNs). The main goal was to develop advanced methods capable of identifying anomalies, and thus potential forgeries, in images with their X-ray photographs. During this research, U-net architectures and binary semantic segmentation techniques were applied, enabling successful anomaly detection. The main contribution of this work is 112 models of four different U-net and U-net++ architectures, which effectively highlight anomalies through the method of binary semantic segmentation. The models were trained on a set of images with their synthetically created X-ray images and artificially generated anomalies. In this way, the models can detect lead spots, nails, layers of hidden paintings, and other defects, while also being able to ignore insignificant elements, such as picture frames and overexposed X-ray images. The testing of the models occurred in two phases. In the first phase, they were evaluated using the IoU metric on a set of 400 synthetically generated data, where in the best cases, they achieved up to 83.5 % IoU. In the second phase, they were evaluated subjectively on images with real X-rays and natural anomalies. This approach combines traditional X-ray techniques with modern computer vision, revealing deviations that might be overlooked during standard visual inspection. By bridging these technologies, this work opens new possibilities for the protection of art collections and provides a solid foundation for further research in the field of art forgery detection using artificial intelligence.
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Visual Anomaly Detection in Industrial Production
Hrabica, Jan ; Richter, Miloslav (referee) ; Horák, Karel (advisor)
This thesis deals with the problem of unary classifiers for anomaly detection in industrial production. It starts with a discussion of classification as a general problem, classification methods and some of their evaluations, and then discusses the main categories of architectures used. Practical part describes the process of scene creation for the acquisitions of a datesed. Acquired dataset is then used for teaching a classifier, on which is then performer a number of experiments to determine its performance.
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Anomaly and threat detection in audit logs using machine learning
Ludes, Adam ; Ježek, Štěpán (referee) ; Tomašov, Adrián (advisor)
Tato práce představuje softwarové architektury založené na cloudu, techniky detekce anomálií, strojové učení a analýzu dat za účelem vytvoření modelu pro detekci anomálií v audit lozích z Red Hat OpenShift Container Platform. Jsou představeny statistické metody a analýza časových řad pro detekci anomálií, zatímco jsou implementovány a hodnoceny modely strojového učení a techniky předzpracování dat. Výsledky ukazují omezení tradičních modelů při zpracování anomálií v hluboce vnořených datech, zatímco model zpracovávající přirozený jazyk prokazuje robustní výkon. Tato práce poskytuje cenné poznatky a může být použita jako reference pro výzkum i praxi v oblasti softwarových architektur založených na cloudu, detekce anomálií, strojového učení a analýzy dat.
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Data Analysis for Predictive Maintenance of a Robotic Arm
Žitný, Roland ; Rozman, Jaroslav (referee) ; Janoušek, Vladimír (advisor)
The Mitsubishi MELFA robotic arms used in modern factories work almost without interruption and produce sensory data about their operation. Various analysis techniques can be applied to such data for predictive maintenance, which provide information on the condition and maintenance needs of such robotic arms. The proposed predictive maintenance process consists of a sensory data acquisition system using the slmpclient and mitsubishi-monitor libraries, an analysis method system with anomaly detection using a convolutional autoencoder, anomaly classification using convolutional neural networks, and data segmentation into segments of individual robot actions using hidden Markov models. Such analysis techniques provide information on the severity, type, and location of emerging faults and abnormalities in behavior, which then determine the time required to perform the required maintenance. This work presents a created chain of predictive maintenance processes, where the obtained findings provide valuable insights into the application of predictive maintenance of Mitsubishi MELFA robotic arms in an industrial environment.
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Detecting RTOS Runtime Anomalies
Arm, Jakub ; Jalovecký, Rudolf (referee) ; Blecha, Petr (referee) ; Bradáč, Zdeněk (advisor)
Due to higher requirements of computational power and safety, or functional safety ofequipments intended for the use in the industrial domain, embedded systems containing areal-time operating system are still the active area of research. This thesis addresses thehardware-assisted control module that is based on the runtime model-based verificationof a target application. This subsystem is intended to increase the diagnostic coverage,particularly, the detection of the execution errors. After the specification of the architecture,the formal model is defined and implemented into hardware using FPGA technology.This thesis also discuss some other aspects and embodies new approaches in the area ofembedded flow control, e.g. the integration of the design patterns. Using the simulation,the created module was tested using the created scenarios, which follow the real programexecution record. The results suggest that the error detection time is lower than usingstandard techniques, such a watchdog.
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Methods for Network Traffic Classification
Jacko, Michal ; Ovšonka, Daniel (referee) ; Barabas, Maroš (advisor)
This paper deals with a problem of detection of network traffic anomaly and classification of network flows. Based on existing methods, paper describes proposal and implementaion of a tool, which can automatically classify network flows. The tool uses CUDA platform for network data processing and computation of network flow metrics using graphics processing unit. Processed flows are subsequently classified by proposed methods for network anomaly detection.
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Automated Processing of Network Service Logs in Linux
Hodermarsky, Jan ; Jeřábek, Jan (referee) ; Ilgner, Petr (advisor)
This thesis is focused on design and implementation of software for a prophylactic real-time logfile analysis and a consequent threat detection apparent therein. The software is to concentre particularly on network services, respectively, on the log files thereof, on Linux platform. The log files are observed for potential security breach attempts in regard to respective service as defined in the configuration file. The present thesis purports to reach the largest extent of versatility possible for a straightforward configuration of a new service which is to be monitored and protected by the software. An important asset of the work is a web-based interface accessible through HTTP protocol which allows the software to be administered remotely with ease.
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Behavioral Analysis of DDoS Network Attacks
Kvasnica, Ondrej ; Homoliak, Ivan (referee) ; Očenášek, Pavel (advisor)
This bachelor thesis deals with anomaly detection in computer networks using artificial intelligence method. Main focus is on the detection of DDoS attacks based on the information from the lower layers of the OSI model. The target is to design and implement a system that is capable of detecting different types of DDoS attacks and characterize common features among them. Selected attacks are SYN flood, UDP flood and ICMP flood. Description and feature selection of the attacks is included. Furthermore, a system is designed that evaluates whether the network traffic (organized into flows) is a DDoS attack or not. Attacks are detected using the XGBoost method, which uses supervised learning. The final model is validated using cross-validation and tested on attacks generated by the author.
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Deep Neural Networks for Defect Detection
Juřica, Tomáš ; Herout, Adam (referee) ; Hradiš, Michal (advisor)
The goal of this work is to bring automatic defect detection to the manufacturing process of plastic cards. A card is considered defective when it is contaminated with a dust particle or a hair. The main challenges I am facing to accomplish this task are a very few training data samples (214 images), small area of target defects in context of an entire card (average defect area is 0.0068 \% of the card) and also very complex background the detection task is performed on. In order to accomplish the task, I decided to use Mask R-CNN detection algorithm combined with augmentation techniques such as synthetic dataset generation. I trained the model on the synthetic dataset consisting of 20 000 images. This way I was able to create a model performing 0.83 AP at 0.1 IoU on the original data test set.
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Automatic quality control of painted metal parts production using neural networks
Ježek, Štěpán ; Kolařík, Martin (referee) ; Burget, Radim (advisor)
This thesis is focused on the problem of visual quality control during painted metal parts fabrication. The main problem of the thesis is the design of automatic quality control method based on modern artificial intelligence and computer vision techniques. Quality control is an important part of a large number of industrial production processes, in which it is necessary to ensure compliance with a number of quality requirements for manufactured products. Until now, quality control is carried out mainly by specialized staff, who are subject to a number of expertise requirements. Currently known methods of visual quality control based on artificial intelligence are characterized by high demands on the size of the training data set and low tolerance for a significant change in position and rotation of the inspected objects relative to the scanning device. As a result of these shortcomings, the use of automated visual quality control in many current industrial applications is impossible. The main contribution of this thesis is the design of a new method for quality control, which shows a strong ability to function reliably even in cases where the above mentioned phenomena of change in position, rotation of objects and lack of training data occur during manufacturing. The accuracy of the method proposed in this thesis is experimentally verified on a data set based on the issue of quality control of painted metal parts. According to the measurement results of defect detection accuracy, the proposed method outperformed other, currently known methods by 10, 25 % using the AUROC metric.
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