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In recent years, the demand for reliable power, driven by sensitive electronic equipment, has surged. Even minor deviations from the nominal supply can lead to malfunctions or failure. Despite technological advancements, power quality issues persist due to various factors like short circuits, overloads, voltage fluctuations, unbalanced loads, and non-linear loads.
This thesis extensively explores power quality anomalies in industrial and commercial sectors, using power system data as the primary analytical resource. It addresses the critical need for power supply reliability in today's evolving power grid industry, affected by non-linear loads, renewable energy integration, and electric vehicles. This field of study is paramount for ensuring power supply reliability and stability in the evolving power grid industry.
The core of this thesis involves a comprehensive investigation of power quality, with a focus on frequency, power, and harmonics in voltage and current signals. The research employs Python programming for advanced data analysis, utilizing techniques such as advanced Fast Fourier Transformation (FFT) analysis. The primary objective is to provide valuable insights aimed at elevating power supply quality and enhancing reliability in both industrial and commercial environments.
Even though the internet has only been there for a short period, it has grown tremendously. To- day, a significant portion of commerce is conducted entirely online because of increased inter- net users and technological advancements in web construction. Additionally, cyberattacks and threats have expanded significantly, leading to financial losses, privacy breaches, identity theft, a decrease in customers’ confidence in online banking and e-commerce, and a decrease in brand reputation and trust. When an attacker pretends to be a genuine and trustworthy institution, they can steal private and confidential information from a victim. Aside from that, phishing has been an ongoing issue for a long time. Billions of dollars have been shed on the global economy. In recent years, there has been significant progress in the development of phishing detection and identification systems to protect against phishing attacks. Phishing detection technologies frequently produce binary results, i.e., whether a phishing attempt was made or not, with no explanation. On the other hand, phishing identification methodologies identify phishing web- pages by visually comparing webpages with predetermined authentic references and reporting phishing together with its target brand, resulting in findings that are understandable. However, technical difficulties in the field of visual analysis limit the applicability of currently available solutions, preventing them from being both effective (with high accuracy) and efficient (with little runtime overhead). Here, we evaluate existed framework called Phishpedia. This hybrid deep learning system can recognize identity logos from webpage screenshots and match logo variants of the same brand with high precision. Phishpedia provides high accuracy with low run- time. Lastly, unlike other methods, Phishpedia does not require training on any phishing sam- ples whatsoever. Phishpedia exceeds baseline identification techniques (EMD, PhishZoo, and LogoSENSE), inaccurately detecting phishing pages in lengthy testing using accurate phishing data. The effectiveness of Phishpedia was tested and compared against other standard machine learning algorithms and some state-of-the-art algorithms. The given solutions performed better than different algorithms in the given dataset, which is impressive.
As the Industry 4.0 is evolving, the previously separated Operational Technology (OT) and Information Technology (IT) is converging. Connecting devices in the industrial setting to the Internet exposes these systems to a broader spectrum of cyber-attacks. The reason is that since OT does not have much security measures as much as IT, it is more vulnerable from the attacker's perspective. Another factor contributing to the vulnerability of OT is that, when it comes to cybersecurity, industries have focused on protecting information technology and less prioritizing the control systems. The consequences of a security breach in an OT system can be more adverse as it can lead to physical damage, industrial accidents and physical harm to human beings. Hence, for the OT networks, certificate-based authentication is implemented. This involves stages of managing credentials in their communication endpoints. In the previous works of ivESK, a solution was developed for managing credentials. This involves a CANopen-based physical demonstrator where the certificate management processes were developed. The extended feature set involving certificate management will be based on the existing solution. The thesis aims to significantly improve such a solution by addressing two key areas that is enhancing functionality and optimizing real-time performance. Regarding the first goal, firstly, an analysis of the existing feature set shall be carried out, where the correct functionality shall be guaranteed. The limitations from the previously implemented system will be addressed and to make sure it can be applied to real world scenarios, it will be implemented and tested in the physical demonstrator. This will lay a concrete foundation that these certificate management processes can be used in the industries in large-scale networks. Implementation of features like revocation mechanism for certificates, automated renewal of the credentials and authorization attribute checks for the certificate management will be implemented. Regarding the second goal, the impact of credential management processes on the ongoing CANopen real-time traffic shall be a studied. Since in real life scenarios, mission-critical applications like Industrial control systems, medical devices, and transportation networks rely on real-time communication for reliable operation, delays or disruptions caused by credential management processes can have severe consequences. Optimizing these processes is crucial for maintaining system integrity and safety. The effect to minimize the disturbance of the credential management processes on the normal operation of the CANopen network shall be characterized. This shall comprise testing real-time parameters in the network such as CPU load, network load and average delay. Results obtained from each of these tests will be studied.
How can manufacturers or service companies provide better services with connected products, without having acquired a powerful IT infrastructure nor the competences for software development?
Today companies can appeal to a relocated-IT-infrastructure provider, which is called Cloud.
Consequently, they do not have to manage and take care of the safety/security aspect, the updates and the breakdown of the infrastructure internally, as those are all managed by the provider.
It is possible to outsource the development of the software of the connected product to an external company. However, the question now is how fast this company can juggle from one Cloud to another in order to fulfil their clients wishes?
neverMind offers a solution based on a multi-protocols-platform linking the different connected products to a multitude of Clouds without having to redesign the whole communication stack/building block for each change in the Cloud-solution. This is the object of my thesis.
The development follows the V-Model, the first steps to understand the complexity of the project were the realisation of the product technical and architectural specifications. The last step before the Implementation was to design in details the progress and the process of every parts of the platform.
The outcome of the requirements analysis led me to divide the project in two parts:
• a “General Interface” acting as a gateway between the Client-application and “Cloud-modules”
• the “Cloud-modules” themselves.
So far, the specifications are drown up; the General Interface and a client example are coded, as well as a first Cloud-module template.
As information technology continues to advance at a rapid speed around the world, new difficulties emerge. The growing number of organizational vulnerabilities is among the most important issues. Finding and mitigating vulnerabilities is critical in order to protect an organization’s environment from multiple attack vectors.
The study investigates and comprehends the complete vulnerability management process from the standpoint of the security officer job role, as well as potential improvements. Few strategies are used to achieve efficient mitigation and the de- velopment of a process for tracking and mitigating vulnerabilities. As a result, a qualitative study is conducted in which the objective is to create a proposed vulner- ability and risk management process, as well as to develop a system for analyzing and tracking vulnerabilities and presenting the vulnerabilities in a graphical dash- board format. This thesis’s data was gathered through an organized literature study as well as through the use of various web resources. We explored numerous ap- proaches to analyze the data, such as categorizing the vulnerabilities every 30, 60, and 90 days to see whether the vulnerabilities were reoccurring or new. According to our findings, tracking vulnerabilities can be advantageous for a security officer.
We come to the conclusion that if an organization has a proper vulnerability tracking system and vulnerability management process, it can aid security officers in having a better understanding of and making plans for reducing vulnerabilities. In terms of system patching and vulnerability remediation, it will also assist the security officer in identifying areas of weakness in the process. As a result, the suggested ways provide an alternate approach to managing and tracking vulnerabilities in an effective manner, although there is still a small area that needs additional analysis and research to make it even better.
This paper describes a project absolved to increase the material flow through the LTCC production of the Bosch Anderson Plant in South Carolina, USA. To archive this goal the regarded value stream is introduced first. The bottleneck, which is limiting the material flow is found and eliminated in order to increase the output of the machine and consequently improve the material flow through the whole value stream. The completed projects made for this purpose result in a 13% increase. To control the material flow the inventory sizes are determined. The inventories, from which the size is desired to be determined, include climatization processes to dry the pastes that are applied in the previous process steps. Therefore, a separation of the parts in the production process climatization and the buffer is necessary first. After that the buffer can be eliminated and the inventory areas minimized. The results are smaller and controlled buffer sizes that make part of the floor space unnecessary. A welcomed side effect is the solution to a production problem of warped parts because of too long climatization times. Observations over time show that the results of the buffer limitations are just right to improve the material flow through the LTCC production.
In the field of network security, the detection of intrusions is an important task to prevent and analyse attacks.
In recent years, an increasing number of works have been published on this subject, which perform this detection based on machine learning techniques.
Thereby not only the well-studied detection of intrusions, but also the real-time capability must be considered.
This thesis addresses the real-time functionality of machine learning based network intrusion detection.
For this purpose we introduce the network feature generator library PyNetFlowGen, which is designed to allow real-time processing of network data.
This library generates 83 statistical features based on reassembled data flows.
The introduced performant Cython implementation allows processing individual packets within 4.58 microseconds.
Based on the generated features, machine learning models were examined with regard to their runtime and real-time capabilities.
The selected Decision-Tree-Classifier model created in Python was further optimised by transpiling it into C-Code, what reduced the prediction time of a single sample to 3.96 microseconds on average.
Based on the feature generator and the machine learning model, an basic IDS system was implemented, which allows a data throughput between 63.7 Mbit/s and 2.5 Gbit/s.
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.
When a patient with hearing aids needs to partake in audiometry procedures they need to visit a specialist which costs both time and money. Ideally, the patient should be able to conduct these tests alone, during their own time, and without additional costs. With this idea comes the question of if whether this is possible or not, and, if it is, how.
This thesis explores the throughput of Bluetooth Low Energy and if it is configurable to have a high enough data rate to send high quality audio data with a lossless audio codec while communicating with a low end device. Additionally, this thesis will show that using Rust to develop embedded software is possible and how using it can make the process of doing so easier.
Linux and Linux-based operating systems have been gaining more popularity among the general users and among developers. Many big enterprises and large companies are using Linux for servers that host their websites, some even require their developers to have knowledge about Linux OS. Even in embedded systems one can find many Linux-based OS that run them. With its increasing popularity, one can deduce the need to secure such a system that many personnel rely on, be it to protect the data that it stores or to protect the integrity of the system itself, or even to protect the availability of the services it offers. Many researchers and Linux enthusiasts have been coming up with various ways to secure Linux OS, however new vulnerabilities and new bugs are always found, by malicious attackers, with every update or change, which calls for the need of more ways to secure these systems.
This Thesis explores the possibility and feasibility of another way to secure Linux OS, specifically securing the terminal of such OS, by altering the commands of the terminal, getting in the way of attackers that have gained terminal access and delaying, giving more time for the response teams and for forensics to stop the attack, minimize the damage, restore operations, and to identify collect and store evidence of the cyber-attack. This research will discuss the advantages and disadvantages of various security measures and compare and contrast with the method suggested in this research.
This research is significant because it paints a better picture of what the state of the art of Linux and Linux-based operating systems security looks like, and it addresses the concerns of security enthusiasts, while exploring new uncharted area of security that have been looked at as a not so significant part of protecting the OSes out of concern of the various limitations and problems it entails. This research will address these concerns while exploring few ways to solve them, as well as addressing the ideal areas and situations in which the proposed method can be used, and when would such method be more of a burden than help if used.