Master of Science

thesisThe moisture content in civil engineering materials determines many of the structural properties of the material such as strength and durability. In geotechnical engineering, the moisture content of soil deposits determines their susceptibility to landslides and settling. In structural engineering, the moisture content in concrete, typically measured in terms of the water-to-cement (w/cm) weight ratio, determines its compressive strength as well as other hardened properties such as permeability and shrinkage. The moisture contents of sand and concrete composites were measured using a handheld microwave moisture meter developed for the purpose of moisture measurements in concrete. The results in concrete obtained from the meter were compared to the results obtained from the standard method of determining moisture content in concrete. In sand, the meter was able to detect the change in moisture content with a linear fit R 2 of 0.962 and 0.945 for the twotypes of sands tested. As for concrete, the linear fit R 2 was as low as 0.0034.The p-values obtained on concrete testing were less than the specified confidence level of 0.05, rejecting the hypothesis that the meter's average output is equal to the average actual w/cm tested. The output w/cm obtained from the meter was compared to moisture content and calculated w/cm from the AASHTO standard method. The linear fit through the data obtained from the test had an R 2 value of 0.62 or higher and a p-value of 0.91, making this methodthe preferred option when wanting accurate in-situ measurements

Impact of Capital Structure on Bank Financial Performance of Al Ahli Bank in Saudi Arabia

This paper seeks to examine the relationship between capital structure and bank financial performance This research had verified the existence of several negative relationships between capital structure (accumulated capital and annual investments) and strategic financial performance, while finding mixed results for the relationship between capital structure (accumulated capital and annual investments) and profitability

Enhanced Microgrid Control through Genetic Predictive Control: Integrating Genetic Algorithms with Model Predictive Control for Improved Non-Linearity and Non-Convexity Handling

\ua9 2024 by the authors.Microgrid (MG) control is crucial for efficient, reliable, and sustainable energy management in distributed energy systems. Genetic Algorithm-based energy management systems (GA-EMS) can optimally control MGs by solving complex, non-linear, and non-convex problems but may struggle with real-time application due to their computational demands. Model Predictive Control (MPC)-based EMS, which predicts future behaviour to ensure optimal performance, usually depends on linear models. This paper introduces a novel Genetic Predictive Control (GPC) method that combines a GA and MPC to enhance resource allocation, balance multiple objectives, and adapt dynamically to changing conditions. Integrating GAs with MPC improves the handling of non-linearities and non-convexity, resulting in more accurate and effective control. Comparative analysis reveals that GPC significantly reduces excess power production, improves resource allocation, and balances cost, emissions, and power efficiency. For example, in the Mutation–Random Selection scenario, GPC reduced excess power to 76.0 W compared to 87.0 W with GA; in the Crossover-Elitism scenario, GPC achieved a lower daily cost of USD 113.94 versus the GA’s USD 127.80 and reduced carbon emissions to 52.83 kg CO2e compared to the GA’s 69.71 kg CO2e. While MPC optimises a weighted sum of objectives, setting appropriate weights can be difficult and may lead to non-convex problems. GAs offer multi-objective optimisation, providing Pareto-optimal solutions. GPC maintains optimal performance by forecasting future load demands and adjusting control actions dynamically. Although GPC can sometimes result in higher costs, such as USD 113.94 compared to USD 131.90 in the Crossover–Random Selection scenario, it achieves a better balance among various metrics, proving cost-effective in the long term. By reducing excess power and emissions, GPC promotes economic savings and sustainability. These findings highlight GPC’s potential as a versatile, efficient, and environmentally beneficial tool for power generation systems

A hybrid method based on logic predictive controller for flexible hybrid microgrid with plug-and-play capabilities

\ua9 2024 The Author(s). Controlling flexible hybrid microgrids (MGs) is difficult due to the system\u27s complexity, which includes multiple energy sources, storage devices, and loads. Although adding new components to the MG system through the plug-and-play (PnP) feature enables operating of the system in different modes, it adds to the system\u27s complexity, hence necessitates careful control system design. The most challenging aspect of designing the control system is ensuring that it can control the MG optimally in its various modes of operation. Previous methods based on logical control allow for synthesizing a controller capable of controlling the MG in its various operational modes. However, the resultant controller does not optimally operate the MG. Classical model predictive control allows optimal control of the MG only in specific operating modes. On the other hand, switched model predictive control (S-MPC) can optimally control the MG in its various modes. However, the design of S-MPC is complex, particularly for MGs with many operating modes or complex switching logic. Multiple factors contribute to the complexity, including model development, mode detection, and switching logic. This paper presents a hybrid method based on ɛ-variables and classical MPC for constructing the S-MPC for flexible hybrid MG with PnP capabilities. Our results show that the proposed controller synthesis approach provides an effective solution for optimally controlling flexible hybrid MGs with PnP capabilities as the proposed method enables: (i) an increase in the amount of energy export to the utility grid by 50.77% and (ii) a significant decrease in the amount of energy import from the grid by 46.7%

Bestimmung des Rotationszentrums des distrahierten Komplexes bei verschiedenen LeFort-Osteotomien Eine Finite-Elemente-Studie

Die Verwendung der Knochenverlängerung bei der Behandlung zahlreicher Gesichtsfehlbildungen in der Mund-, Kiefer- und Kraniogesichtschirurgie gilt mittlerweile als unverzichtbare therapeutische Methode. Die computergestützten Simulationen führen zu einem besseren Verständnis der physikalischen Eigenschaften des Behandlungsprozesses, welches am lebenden Patienten direkt nicht zu erreichen ist. Das Ziel der vorliegenden Arbeit war die Bestimmung des Rotationszentrums im Rahmen der Knochenverlängerung bei drei verschiedenen simulierten Knochensegmenten (LeFort-I, II und III). Ein Master-Modell (849921 Elemente, 221064 Knoten) wurde durch 3D-Modell-entwicklung eines menschlichen Gesichtsschädels hergestellt, indem Primärdaten von einer Computertomographie des Kopfes einer anonymisierten jungen Patientin, übertragen wurden. In dem Modell wurden vier Masken identifiziert: kortikaler Knochen, spongiöser Knochen, Zähne und Weichgewebe. Von dem Master-Modell wurden drei Kopien angefertigt, an denen jeweils eine Osteotomie (LeFort-I, II und III) simuliert wurde. Um den Einfluss des Weichgewebes und der Kallus-Elastizität auf die Lageänderung des Rotationszentrums besser darzustellen, wurden verschiedene Elastizitäts- und Kontaktparameter vom Kallus und Weichgeweben verwendet, damit entstanden 18 Simulationmodelle. Die maxilläre Komponente wurde in jedem Fall in der sagittalen Ebene um 0,5 mm durch Zugkräfte verlagert. Die verlagerte maxilläre Komponente zeigte komplexe dreidimensionale Bewegungen. Das Rotationszentrums der maxillären Komponente wurde nur in der sagittalen Ebene analysiert. Die Lageänderung des Rotationszentrums wurde in allen Simulationen anhand von drei Werten, zwei Winkeln und einem Verhältnis, bestimmt. Im Rahmen dieser Studie konnte der Einfluss der verschiedenen Faktoren (Weichgewebe, Kallus E-Modul und Osteotomielinie) auf die Lage des Rotationszentrums gezeigt werden

Analysis of the Impact of Fintech Firms’ Lending on the Expansion of Service Base Companies in Jordan

The purpose of this research was to analyze the impact of lending by fintech firms on the expansion of service- based companies in Jordan. The studys population included 210 service-based enterprises located in Jordan. The research used a sample size of 136 respondents from registered service-based enterprises in Jordan. The researchers used a structured questionnaire to gather data from the participants. The data acquired in this study were evaluated using a combination of basic percentage calculations and Pearson product moment analysis. The research has reached the conclusion that the lending activities of Fintech firms have a noteworthy impact on the expansion of service-based companies in Jordan. The study suggests that it would be advantageous for the Fintech service provider to engage in advertising efforts aimed at promoting their services, with the goal of increasing the adoption of their mobile money product among a wider range of business professionals. This would lead to an increased number of entrepreneurs using Fintech as a means to augment the expansion of their businesses. The scope of the research was limited to a small number of service-based organizations. However, it is important to include other service-based companies that were not included in this study. To get a comprehensive understanding, a comparison study should be conducted to explore other characteristics that were not addressed in the current research. The field of financial technology (fintech) has seen significant growth in recent years. This growth can be measured by the degree of utilization observed in various fintech applications and services

Primary frequency response from hydrogen-based bidirectional vector coupling storage:modelling and demonstration using power-hardware-in-the-loop simulation

To meet reduction targets for carbon emissions and improve the flexibility and security of the energy supply, future energy networks will require enhanced energy vector coupling in addition to the generation of energy from renewable sources. Increased renewable generation penetration significantly affects the electrical grid’s inertia and consequently the severity and regularity of frequency deviations from nominal values. Bidirectional Hydrogen-based Vector Coupling Storage (VCS) has been explored as a means to provide primary frequency response (PFR) services to the electrical network. This paper demonstrates the use of Power Hardware-In-the-Loop (PHIL) simulation and Digital Twin (DT) technique for such an application. This new suggested structure of VCS is composed of grid-scale electrolysers, fuel cells, and hydrogen storage. Existing works focus on unidirectional VCS, and also use simplifications or neglect the impacts of power converters on the performance of the VCS. In addition, these works do not have any control over the hydrogen storage, therefore there is no guarantee that there will be enough energy available in the storage to meet the PFR service responsibilities. This paper presents the dynamic models of electrolysis, fuel cell stacks, and hydrogen storage as a DT. The key parameters affecting the behaviours of these main components are considered. The power converters’ accurate impact on the VCS’s performance is considered through PHIL simulations. The level of stored hydrogen is also considered in the VCS controller. The DT representing the VCS is integrated with the PHIL setup representing the deployment environment. The impact of VCS is then analysed as it propagates to the deployment environment. Results of the considered case studies demonstrate that the size of the VCS plays a significant role in bringing the frequency to the statutory allowed range. In addition, more VCS capacity was installed, the nadir frequency improved. Furthermore, the VCS is fast enough to offer PFR. The response times of the VCS were 2.857 s (during under-frequency periods), corresponding to the operation of the fuel cells, and 2.252 s during over-frequency periods, corresponding to electrolyser operation.</p

Multi-port coordination: Unlocking flexibility and hydrogen opportunities in green energy networks

\ua9 2024Seaports are responsible for consuming a large amount of energy and producing a sizeable amount of environmental emissions. However, optimal coordination and cooperation present an opportunity to transform this challenge into an opportunity by enabling flexibility in their generation and load units. This paper introduces a coordination framework for exploiting flexibility across multiple ports. The proposed method fosters cooperation between ports in achieving lower environmental emissions while leveraging flexibility to increase their revenue. This platform allows ports to participate in providing flexibility for the energy grid through the introduction of a green port-to-grid concept while optimising their cooperation. Furthermore, the proximity to offshore wind farms is considered an opportunity for the ports to investigate their role in harnessing green hydrogen. The proposed method explores the hydrogen storage capability of ports as an opportunity for increasing the techno-economic benefits, particularly through coupling them with offshore wind farms. Compared to existing literature, the proposed method enjoys a comprehensive logistics-electric model for the ports, a novel coordination framework for multi-port flexibility, and the potentials of hydrogen storage for the ports. These unique features position this paper a valuable reference for research and industry by demonstrating realistic cooperation among ports in the energy network. The simulation results confirm the effectiveness of the proposed port flexibility coordination from both environmental and economic perspectives

Towards 2050 net zero carbon infrastructure:a critical review of key decarbonization challenges in the domestic heating sector in the UK

One of the most challenging sectors to meet “Net Zero emissions” target by 2050 in the UK is the domestic heating sector. This paper provides a comprehensive literature review of the main challenges of heating systems transition to low carbon technologies in which three distinct categories of challenges are discussed. The first challenge is of decarbonizing heat at the supply side, considering specifically the difficulties in integrating hydrogen as a low-carbon heating substitute to the dominant natural gas. The next challenge is of decarbonizing heat at the demand side, and research into the difficulties of retrofitting the existing UK housing stock, of digitalizing heating energy systems, as well as ensuring both retrofits and digitalization do not disproportionately affect vulnerable groups in society. The need for demonstrating innovative solutions to these challenges leads to the final focus, which is the challenge of modeling and demonstrating future energy systems heating scenarios. This work concludes with recommendations for the energy research community and policy makers to tackle urgent challenges facing the decarbonization of the UK heating sector.</p

Integration of Supply Chains and Operational Performance: The Moderating Effects of Knowledge Management

Supply chain integration (SCI) is a strategic process management technique that may be used to boost an organizations performance and thereby gain a competitive edge. The purpose of this paper is to demonstrate both the direct effect of (SCI) on manufacturing firms operational performance and the moderating effect of knowledge management (KM) on the relationship between supplier integration (SI), customer integration (CI), internal integration (II), and operational performance (OP). The study analyzed survey data from 277 Jordanian manufacturing and industrial businesses using the PLS–Structural Equation method. According to the data, (CI), (II), and (SI) are all positively and significantly associated with operational success. (CI), (II), and (SI) all have a strong and beneficial moderate relationship with (OP). There is, however, no connection between (KM) and (OP). Furthermore, further research may be conducted to assess the applicability of the findings from this study to other populations of varied sizes in other countries. A long-term study that tracks the growth of different measures might provide further insight on the relationship between SCI and OP