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AI-based Ground Penetrating Radar Signal Processing for Thickness Estimation of Subsurface Layers
(2023)
This thesis focuses on the estimation of subsurface layer thickness using Ground Penetrating Radar (GPR) A-scan and B-scan data through the application of neural networks. The objective is to develop accurate models capable of estimating the thickness of up to two subsurface layers.
Two different approaches are explored for processing the A-scan data. In the first approach, A-scans are compressed using Principal Component Analysis (PCA), and a regression feedforward neural network is employed to estimate the layers’ thicknesses. The second approach utilizes a regression one-dimensional Convolutional Neural Network (1-D CNN) for the same purpose. Comparative analysis reveals that the second approach yields superior results in terms of accuracy.
Subsequently, the proposed 1-D CNN architecture is adapted and evaluated for Step Frequency Continuous Wave (SFCW) radar, expanding its applicability to this type of radar system. The effectiveness of the proposed network in estimating subsurface layer thickness for SFCW radar is demonstrated.
Furthermore, the thesis investigates the utilization of GPR B-scan images as input data for subsurface layer thickness estimation. A regression CNN is employed for this purpose, although the results achieved are not as promising as those obtained with the 1-D CNN using A-scan data. This disparity is attributed to the limited availability of B-scan data, as B-scan generation is a resource-intensive process.
Global energy demand is still on an increase during the last decade, with a lot of impact on the climate change due to the intensive use of conventional fossil-based fuels power plants to cover this demand. Most recently, leaders of the globe met in 2015 to come out with the Paris Agreement, stating that the countries will start to take a more responsible and effective behaviour toward the global warming and climate change issues. Many studies have discussed how the future energy system will look like with respecting the countries’ targets and limits of greenhouse gases and their CO2 emissions. However, these studies rarely discussed the industry sector in detail even though it is one of the major role players in the energy sector. Moreover, many studies have simulated and modelled the energy system with huge jumps of intervals in terms of years and environmental goals. In the first part of this study, a model will be developed for the German electrical grid with high spatial and temporal resolutions and different scenarios of it will be analysed meticulously on shorter periods (annual optimization), with different flexibilities and used technologies and degrees of innovations within each scenario. Moreover, the challenge in this research is to adequately map the diverse and different characteristics of the medium-sized industrial sector. In order to be able to take a first step in assessing the relevance of the industrial sector in Germany for climate protection goals, the industrial sector will be mapped in PyPSA-Eur (an open-source model data set of the European energy system at the level of the transmission network) by detailing the demand for different types of industry and assigning flexibilities to the industrial types. Synthetically generated load profiles of various industrial types are available. Flexibilities in the industrial sector are described by the project partner Fraunhofer IPA in the GaIN project and can be used. Using a scenario analysis, the development of the industrial sector and the use of flexibilities are then to be assessed quantitatively.
One of the main problematics of the seals tests is the time and money consuming they are. Up to now, there are few tries to do a digitalisation of a test where the seals behaviour can be known.
This work aims to digitally reproduce a seal test to extract their behaviour when working under different operation conditions to see their impact on the pimp’s efficiency. In this thesis, due to the Lomaking effect, the leakage and the forces applied on the stator will be the base of analysis.
First of all, among all the literature available for very different kind of seals and inner patterns, it has been chosen the most appropriate and precise data. The data chosen is “Test results for liquid Damper Seals using a Round-Hole Roughness Pattern for the Stator” from Fayolle, P. and “Static and Rotordynamic Characteristics of Liquid Annular Seals with Circumferentially/Grooved Stator and Smooth Rotor using three levels of circumferential Inlet-Fluid” from Torres J.M.
From the literature, dimensions of the test rig and the seals will be extracted to model them into a 3D CAD software. With the 3D CAD digitalisation, the fluid volumes for a rotor-centred position, meaning without eccentricity, will be extracted, and used. The following components have been modelled:
- Smooth Annular Liquid Seal (Grooved Rotor)
- Grooved Annular Liquid Seal (Smooth Rotor)
- Round-Hole Pattern Annular Liquid Seal (𝐻𝑑=2 𝑚𝑚) (Smooth Rotor)
- Straight Honeycomb Annular Liquid Seal (Smooth Rotor)
- Convergent Honeycomb Annular Liquid Seal (Smooth Rotor)
- Smooth Rotor / Smooth Annular Liquid Seal (Smooth Rotor)
As there is just one test rig, all the components have been adapted to the different dimensions of the seals by referencing some measures. This allows to test any seal with the same test rig.
Afterwards a CFD simulation that will be used to obtain leakage and stator forces. The parameters that will be changed are the rotational velocity of the fluid (2000 rpm, 4000 rpm, and 6000 rpm) and the pressure drop (2,068 bar, 4,137 bar, 6,205 bar, and 8,274 bar).
Those results will be compared to the literature ones, and they will determine if digitalisation can be validated or not. Even though the relative error is higher than 5% but the tendency is the same and it is thought that by changing some parameters the test results can be even closer to the literature ones.
To date, many experiments have been performed to study how the internal geometrical shapes of the annular liquid seal can reduce internal leakage and increase pump efficiency. These can be time-consuming and expensive as all rotordynamic coefficients must be determined in each case.
Nowadays, accurate simulation methods to calculate rotordynamic coefficients of annular seals are still rare. Therefore, new numerical methods must be designed and validated for annular seals.
The present study aims to contribute to this labour by providing a summary of the available test rig and seals dimensions and experimental results obtained in the following experiments:
− Kaneko, S et al., Experimental Study on Static and Dynamic Characteristics of Liquid Annular Convergent-Tapered Seals with Honeycomb Roughness Pattern (2003) [1] − J. Alex Moreland, Influence of pre-swirl and eccentricity in smooth stator/grooved rotor liquid annular seals, static and rotordynamic characteristics (2016) [2]
A 3D CAD simulation with Siemens NX Software of the test rig used in J. Alex Moreland’s experiment has been made. The following annular liquid seals have also been 3D modelled, as well as their fluid volume:
− Smooth Annular Liquid Seal (SS/GR) (J. Alex Moreland experiment)
− Grooved Annular Liquid Seal (GS/SR)
− Round-Hole Pattern Annular Liquid Seal (𝐻𝑑=2 mm) (GS/SR)
− Straight Honeycomb Annular Liquid Seal (GS/SR)
− Convergent Honeycomb Annular Liquid Seal (No. 3) (GS/SR)
− Smooth Annular Liquid Seal (SS/SR) (S. Kaneko experiment)
In the case of the seals used in S. Kaneko’s experiments, the test rig has been adapted to each seal, defining interpart expressions which can be easily modified.
Afterwards, it has been done a CFD simulation of the Smooth Annular Liquid Seal using Ansys CFX Software. To do so, the fluid volume geometry has been simplified to do a first approximation. Results have been compared for an eccentricity 𝜀0=0.00 for the following ranges of rotor speeds and differential of pressure:
− Δ𝑃= 2.07, 4.14, 6.21, and 8.27 bar,
− 𝜔= 2, 4, 6 and 8 krpm.
Even results obtained have the same trend as the one proportionated by the literature, they cannot be validated as the error is above 5%. It is also observed that as the pressure drop increases, the relative error decreases considerably.
The Lattice Boltzmann Method is a useful tool to calculate fluid flow and acoustic effects at the same time. Although the acoustic perturbation is much smaller than normal pressure differences in fluid flow, this direct calculation is a great advantage of the Lattice Boltzmann Method (LBM). But each border used in calculation produces a multitude of reflections with the acoustic waves, which lead to an unusable result. Therefore, it is worked on different absorbing techniques.
In this thesis three absorbing layer techniques are described, explained and reviewed with different simulations. The absorbing layers are implemented in a basic LBM code in C++, and with this umpteen simulations within a box were performed to compare the different absorbing layers. The Doppler effect and a cylinder flow are also examined to compare the damping efficiencies.
The three studied absorbing techniques are the sponge layer, the perfectly matched layer and a force based Term II absorbing layer. The sponge layer is easy to implement but gives worse results than a calculation without any absorbing layer. The perfectly matched layer and a force based absorbing term provide very good results but the perfectly matched layer has problems with instability. The force based absorbing layer represents the best compromise between the additional computation time due the absorbing layer and the achieved damping efficiency.
Truth is the first causality of war”, is a very often used statement. What rather intrigues the mind is what causes the causality of truth. If one dives deeper, one may also wonder why is this so-called truth the first target in a war. Who all see the truth before it dies. These questions rarely get answered as the media and general public tends to focus more on the human and economic losses in a war or war like situation. What many fail to realize is that these truthful pieces of information are critical to how a situation further develops. One correct information may change the course of the whole war saving millions and one mis-information may do the opposite.
Since its inception, some studies have been conducted to propose and develop new applications for OSINT in various fields. In addition to OSINT, Artificial Intelligence is a worldwide trend that is being used in conjunction witThe question here is, what is this information. Who transmits this and how? What is the source. Although, there has been an extensive use of the information provided by the secret services of any nation, which have come handy to many, another kind of information system is using the one that is publicly available, but in different pieces. This kind of information may come from people posting on social media, some publicly available records and much more. The key part in this publicly available information is that these are just pieces of information available across the globe from various different sources. This could be seen as small pieces of a puzzle that need to be put together to see the bigger picture. This is where OSINT comes in place.
h other areas (AI). AI is the branch of computer science that is in charge of developing intelligent systems. In terms of contribution, this work presents a 9-step systematic literature review as well as consolidated data to support future OSINT studies. It was possible to understand where the greatest concentration of publications was, which countries and continents developed the most research, and the characteristics of these publications using this information. What are the trends for the next OSINT with AI studies? What AI subfields are used with OSINT? What are the most popular keywords, and how do they relate to others over time?A timeline describing the application of OSINT is also provided. It was also clear how OSINT was used in conjunction with AI to solve problems in various areas with varying objectives. Private investigators and journalists are no longer the primary users of open-source intelligence gathering and analysis (OSINT) techniques. Approximately 80-90 percent of data analysed by intelligence agencies is now derived from publicly available sources. Furthermore, the massive expansion of the internet, particularly social media platforms, has made OSINT more accessible to civilians who simply want to trawl the Web for information on a specific individual, organisation, or product. The General Data Protection Regulation (GDPR) of the European Union was implemented in the United Kingdom in May 2018 through the new Data Protection Act, with the goal of protecting personal data from unauthorised collection, storage, and exploitation. This document presents a preliminary review of the literature on GDPR-related work.
The reviewed literature is divided into six sections: ’What is OSINT?’, ’What are the risks?’ and benefits of OSINT?’, ’What is the rationale for data protection legislation?’, ’What are the current legislative frameworks in the UK and Europe?’, ’What is the potential impact of the GDPR on OSINT?’, and ’Have the views of civilian and commercial stakeholders been sought and why is this important?’. Because OSINT tools and techniques are available to anyone, they have the unique ability to be used to hold power accountable. As a result, it is critical that new data protection legislation does not impede civilian OSINT capabilities.
In this paper we see how OSINT has played an important role in the wars across the globe in the past. We also see how OSINT is used in our everyday life. We also gain insights on how OSINT is playing a role in the current war going on between Russia and Ukraine. Furthermore, we look into some of these OSINT tools and how they work. We also consider a use case where OSINT is used as an anti terrorism tool. At the end, we also see how OSINT has evolved over the years, and what we can expect in the future as to what OSINT may look like.
One of the most critical areas of research and expansion has been exploiting new technologies in supply chain risk management. One example of this is the use of Digital Twins. The performance of physical systems can be analyzed and simulated using digital twins, virtual versions of these systems that use real-time data, and sophisticated algorithms. Inside the supply chain risk management field, digital twins present a one-of-a-kind opportunity to improve an organization's ability to anticipate, address, and react to the possibility of problems within the supply chain.
The objective of this study is to identify and assess the advantages that accrue to supply chain risk management as a result of Digital Twins' adoption into the system, as well as to identify the challenges associated with achieving those benefits. In the context of supply chain risk management, a thorough literature study is conducted to analyze the essential traits and capabilities of digital twins and how these qualities lead to enhanced risk management methods. This study investigates the essential properties and capacities of digital twins. In addition, the state of digital twin technology and its applications in supply chain risk management are evaluated, and prospective areas for further study and development are highlighted.
The primary purpose of this investigation is to provide a comprehensive and in-depth analysis of the digital twins' role in supply chain risk management through the utilization of digital twins, as well as to highlight the potential benefits and challenges associated with the implementation of digital twins. The research was carried out based on the existing body of written material and the replies of 27 individuals who had previous experience making use of digital twins and took part in an online questionnaire.
The results of this study will be relevant to a diverse group of stakeholders, including specialists in risk management and researchers, amongst others.
Android is the most popular mobile operating system. Its omnipresence leads to the fact that it is also the most popular target amongst malware developers and other computer criminals. Hence, this thesis shows the security-relevant structures of Android’s system and application architecture. Furthermore, it provides laboratory exercises on various security-related issues to understand them not only theoretically but also deal with them in a practical way. In order to provide infrastructure-independent education, the exercises are based on Android Virtual Devices (AVDs).
Total Cost of Ownership (TCO) is a key tool to have a complete understanding of the costs associated with an investment, as it allows to analyze not only the initial acquisition costs, but also the long-term costs related to operation, maintenance, depreciation, and other factors. In the context of the cement industry, TCO is especially important due to the complexity of the production processes and the wide variety of components and machinery involved in the process.
For this reason, a TCO analysis for the cement industry has been conducted in this study, with the objective of showing the different components of the cost of production. This analysis will allow the reader to gain knowledge about these costs, in the industrial model will be to make informed decisions on the adoption of technologies and practices that will allow them to reduce costs in the long run and improve their operational efficiency.
In particular, this study pursues to give visibility to technologies and practices that enable the reduction of carbon emissions in cement production, thus contributing to the sustainability of industry and the protection of the environment. By being at the forefront of sustainability issues, the cement industry can contribute to the achievement of environmentally friendly technologies and enable the development of people and industry.
The Oxyfuel technology has been selected as a carbon capture solution for the cement industry due to its practical application, low costs, and practical adaptation to non-capture processes. The adoption of this technology allows for a significant reduction in CO2 emissions, which is a crucial factor in achieving sustainability in the cement manufacturing process.
Carbon capture storage technologies represent a high investment, although these technologies increase the cost of production, the application of Oxyfuel technology is one of the most economically viable as the cheapest technology per capture according to the comparison. However, this price increase is a technical advantage as the carbon capture efficiency of this technology reaches 90%. This level of efficiency leads to a decrease in taxes for the generation of CO2 emissions, making the cement manufacturing process sustainable.
In each company Top Managers have the responsibility to take major decisions that supports the success of their company, Adopting TQM is one of these decisions, the decision to carry out companies’ operations and procedures within TQM frameworks. (ASQ , n.d.). Applying TQM, involves implementing practices that needs putting extra efforts, otherwise there will be no use of the practices and the execution. (Nicca Jirah F Campos1, 2022).
Specifically in service sector, where the key to success and increased profit, comes directly through a satisfied customer. Therefor there is a need for both management and staff to have big tolerance and willingness to achieve the needed satisfaction, in order to attain the results that every company wants. (Charantimath, 2013)
In Germany in terms of customer care practices there is a famous stereotype ‘Customer is not the king’ A reputation That after DW investigated it, DW expressed it as a phenomenon where both expats and Germans tend to believe that service companies in Germany should do a better job of treating their consumers. (DW, 2016)
New concepts of business have emerged in the late century, for example strategy, leadership, marketing, entrepreneurship and others, these concepts spread internationally among most of the companies around the world. Many studies have been done reviewing these new business structures, some of them addressed the cultural differences within countries upon the applying them. But not many studies concentrated on taking into consideration how cultural differences affects the Implementation of TQM. (Lagrosen, 2002). It was concluded in general that although the comprehensive fundamentals of quality management are applicable and similar worldwide in all nations, but when coming to real practice accurate tunning must be made, it must be taken into account aligning different standards, due to different work cultures and traditions in Europe. (Krueger, 1999)