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ÖgeDetermination of greenhouse gas emissions; Case study for a turkish marine technology company(Graduate School, 2024-10-25)Global warming poses serious risks both today and in the future. The increase in global temperature poses serious problems such as climate change, sea level rise, ecosystem degradation, decrease in agricultural productivity, and depletion of water resources. The increase in human-induced greenhouse gases forms the basis of global warming. As a result of the growing concern about greenhouse gas emissions (GHG), international initiatives to control and take measures in this area are increasing and gaining importance. In addition to the obligations imposed by international deposits, businesses also have social responsibilities to ensure a sustainable future. In this context, carbon footprint assessments are one of the most important tools for switching to more environmentally friendly operations. As an energy-intensive sector, the maritime industry causes important amounts of air emissions, particularly GHGs. Most of the research on GHG reduction from shipping focuses on reducing emissions during the operational phase. However, as emissions during ship operations are reduced, ships' construction, dismantling, and maritime technology generation phases become increasingly important. This thesis includes carbon emissions and calculations from a maritime organization and its activities. It is within the scope of the thesis to determine the standards and methods used in calculations by processing the corporate carbon footprint. The case study conducted for a marine technology company operating in Türkiye aims to set an example in determining the carbon footprint, contribute to the sustainability performance of the sector by examining the environmental impacts of maritime companies, and guide future studies. Within the scope of the research, in order to calculate the corporate carbon footprint (CF) according to the criterias specified in the GHG Protocol and ISO 14064, firstly, the activity boundaries are determined by determining information such as the use of transport vehicles, the types of energy used and the wastes generated. Scope-1, Scope-2, and Scope-3 emission sources are classified. After these emission sources are identified, the necessary data are obtained from the maritime technologies enterprise to calculate the carbon footprint. Emission factors published in the Department for Environment, Food and Rural Affairs (DEFRA) notifications are included in the data pool. Corporate carbon footprint calculation is carried out by multiplying the data obtained from the maritime technologies enterprise with the relevant emission factors and obtaining emission data in terms of carbon dioxide equivalent (CO2e) according to the activities. In the study, direct and indirect emissions of the maritime technologies business are calculated within the determined operational limits. As a result of the calculations made, the scope I emissions of the examined facility are determined as 85,791 tons of CO2e, mainly from mobile combustion, scope II emissions from purchased electricity are determined as 51,455 tons of CO2e, while scope III emissions, which are mostly not included in scope I sources and are indirectly caused by fuel consumption, are determined as 42,079 tons CO2e. According to these results, the total greenhouse gas emission of the marine technologies enterprise examined within the scope of the study is 179,325 tons of CO2e according to 2023 data. In the study, it is observed that 47.86% of the total greenhouse gas emissions are Scope I emissions, 28.69% are Scope II emissions and 23.46% are Scope III emissions. The results will provide a comprehensive overview of the facility's carbon emissions from various sources and help identify key areas for potential reductions in GHG emissions. According to the results of the carbon footprinting for the maritime technologies business enterprise, strategies that can be followed according to emission sources in all three scopes to reduce greenhouse gas emissions are shared. The data obtained provide a critical basis for understanding the environmental impacts of various aspects of maritime activities. These results will contribute to guiding the sustainability efforts of maritime businesses and their commitment to leaving a cleaner environment for future generations. Future studies will have an important role in monitoring the effectiveness of these measures and continuously improving the environmental performance of the maritime business.
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ÖgeThe use of hybrid energy storage systems in commercial vessels and potential contribution to emission reduction in Turkish straits(Graduate School, 2023)In this thesis use of hybrid energy storage systems (HESS) in commercial ships's auxiliary power system (not for propulsion) was investigated in terms of emission reduction during maneuvering and strait passages. For the HESS proposed in this thesis, the appropriate battery group has been determined for a 10-year service period, taking into account the characteristics of the battery types to be used as well as the load characteristics of the ship. In the first part of the study a hypothetical study was carried out on a real commercial tanker vessel sailing in Turkey's inland waters and frequently using the Çanakkale and Istanbul straits. First of all, the actual fuel consumption data of the ship was analyzed and the emissions and fuel consumption during local maneuvers and channel navigation were evaluated on a 2-year basis. Afterwards, the same parameters were then evaluated for the case of having a hybrid energy storage system for the auxiliary power system on board. These analyses show that the use of hybrid auxiliary systems on commercial vessels leads to a reduction in local emissions. In the second part of the study, using the annual maritime traffic data of the Istanbul and Çanakkale straits, which have the highest maritime traffic in Turkey, the potential emission reductions in the straits were calculated if ships transiting these straits used a hybrid energy system instead of keeping two generators running to ensure the operational continuity of their auxiliary systems. In this context; The components of hybrid energy systems used on-board ships and their decisive criteria have been checked. Battery types which are used in Battery-Hybrid systems have been checked. Engineering and operational challenges such as power fluctuations which must be compensated, have been investigated.
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ÖgeLanding dampers for aircraft carrier decks(Graduate School, 2024-07-09)Shock absorbers are integral components in mitigating landing events, especially within the context of aircraft carrier landing gear design, where the formidable impact forces of horizontal or vertical landings are prevalent. Typically crafted from elastomeric materials such as pads or cables, these shock absorbers are meticulously engineered to absorb and dissipate energy upon the abrupt contact of an aircraft with the carrier deck, thus effectively reducing the force of impact. The primary objective of this study is to undertake a comprehensive analysis and evaluation of the performance exhibited by landing dampers employed during landing operations on aircraft carrier decks. This endeavour involves a multifaceted approach that encompasses various methodologies including data analysis, numerical modelling, simulations, and real-world testing. Through this concerted effort, the efficacy of these dampers is being rigorously assessed to provide a holistic understanding of their functionality. Moreover, this study endeavours to embark on the development of shock absorber designs tailored specifically for ship decks, based on the insights garnered from the aforementioned analyses. These designs are then subjected to dynamic analysis to ascertain their structural integrity and operational efficiency under realistic conditions. By leveraging advanced analytical techniques, this phase aims to optimize shock absorber designs, thereby enhancing their performance and reliability during landing operations on aircraft carrier decks. Furthermore, a comparative analysis is being conducted to juxtapose the functionality of shock-absorbing deck designs against their non-shock-absorbing counterparts. This comparative study seeks to elucidate the distinct advantages and efficacy offered by the integration of landing dampers into aircraft carrier deck configurations. By highlighting the inherent benefits of shock-absorbing deck designs, this analysis underscores their pivotal role in bolstering the safety and operational efficiency of aircraft carrier landings. In conclusion, the findings of this study are poised to make significant contributions to the field of maritime engineering by enhancing our understanding of landing dampers and their impact mitigation capabilities. By optimizing shock absorber designs and elucidating their advantages, this research endeavour not only augments the safety and operational efficiency of aircraft carrier landings but also furnishes invaluable insights for the optimization of shock absorber designs in diverse maritime environments.
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ÖgeComprehensive assessment of rov systems: An effective approach to analysis of ROV system mobilization risks(Graduate School, 2023-06-12)Remote Operating Vehicles (ROVs) are sophisticated underwater robots that play a vital role in various industries such as deep-sea exploration, oil and gas operations, underwater construction, and scientific research. These ROV systems consist of several components, including the ROV itself, Launch and Recovery Systems (LARS), umbilical cables, tethers, and power generators. Due to their complexity, it is crucial to conduct a thorough risk analysis to identify and mitigate potential hazards associated with ROV operations. This study specifically focuses on the mobilization phase of ROV systems, which involves preparing and deploying the underwater robots. During mobilization, numerous risks can arise, including mechanical or technical failures during transportation, damage to the ROV or its components during handling, and delays or disruptions caused by adverse weather conditions or logistical issues. Safeguarding against these risks is paramount to ensure the safe and successful operation of ROVs. To assess the risks involved in the mobilization process, two hybrid approaches are employed in this study. Both methods utilize the Ordered Weighted Geometric Average (OWGA) for weight distribution in terms of Severity, Detection, and Occurrence. In addition, Multi-Objective Optimization on the Basis of Ratio Analysis (MOORA) and Multi-Objective Optimization on the Basis of Simple Ratio Analysis (MOOSRA) are utilized in calculating the Risk Priority Number (RPN). These approaches aim to provide a comprehensive evaluation of the risks associated with ROV mobilization, taking into account various factors and expert opinions. By utilizing these hybrid methodologies, operators and stakeholders can gain a better understanding of the potential risks involved and make informed decisions to mitigate them effectively. In conclusion, the analysis of risks in ROV systems, particularly during the mobilization phase, is crucial for ensuring safe and successful operations. By employing hybrid approaches and incorporating expert opinions, this study aims to enhance risk assessment capabilities and facilitate the implementation of effective risk mitigation strategies in the field of underwater robotics.
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ÖgePotential wind farm design of the Caspian sea shores of Azerbaijan(Graduate School, 2022-06-23)Renewable energy sources include the sun, wind, water, the Earth's heat, and plants, all of which are perpetually renewed by nature. Renewable energy technologies convert these fuels into useable energy, such as electricity, heat, chemicals, or mechanical energy. Fossil fuels are now utilized to heat and power houses, as well as to fuel automobiles. Coal, oil, and natural gas are convenient for providing our energy demands, but there is a finite quantity of these fuels on the planet. We're consuming them at a far faster rate than they're being generated. They'll eventually run out. And, due to safety concerns and waste disposal issues, the US will phase down much of its nuclear power capacity by 2020. Meanwhile, the country's energy demands are predicted to increase by 33% during the next 20 years. Renewable energy may be able to fill the void. Renewable energy is better for the environment even if we had a limitless supply of fossil resources. Renewable energy systems are frequently referred to as "clean" or "green" since they create little, if any, pollutants. Renewable energy will also assist us in achieving energy security and independence. Replacing part of our petroleum with plant-based fuels, for example, may save money while also increasing our energy security. Renewable energy is abundant, and technology is always improving. Renewable energy may be used in a variety of ways. In our daily lives, the majority of us currently utilize renewable energy. The design of the wind farm has been researched in the fourth chapter. This section focuses on selecting the best site for the wind farm. The situation of the wind blowing around the Absheron area is described in general. The absheron region appears to be typically adequate in terms of wind speed when we look at the wind maps during the studies. In terms of depth, it appears that the region's depth ranges between 20 and 40 meters. On the other hand, the presence of onshore wind farms in the northern half of the Absheron peninsula makes this region more grid-connected. In terms of wind speed, the location in the southern portion of the Absheron peninsula where the wind speed of 7.69 m/sec was found to be the most favorable (A region). However, as previously noted, the sea section in the northern half of the Absheron peninsula is the best location for grid connection. Part B, in one of the zones with the highest wind speed closest to the land, has been judged to be the most suited location. The greatest water depth in this area is 20 meters, and the monopile foundations for the wind turbines to be erected are considered adequate. Furthermore, it has been found that ship traffic is not a barrier for this region, and as is well known, Azerbaijan has oil and natural gas deposits in the Caspian, and there is no pipeline running through this region, despite the threat of underwater pipes. The Vestas117-4.2 MW model was chosen as the wind turbine's model. Because the selected wind turbine's hub height is 91.5 meters, a reference wind speed of 50 meters (8.25 m/sec) was used, and the wind speed at 91.5 meters was found to be 8.7 m/sec. Furthermore, the annual energy production of a wind turbine was calculated based on its data to be 14.7 GWAC/year