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    Assessment of Co2 measurements based on exergetic approach for low carbon standards in buildings
    (Springer Verlag, 2018) Söğüt, M. Ziya; Karakoç, T. Hikmet; Ekmekçi, İsmail
    CO2 emission criteria have different approach for many countries. These approaches are not sufficient to define regarding global effect based on the loads of emission. Although depending on the extent of the IPCC criteria (Intergovernmental Panel on Climate Change) and particularly high entropy production, fossil energy sources are rapidly increasing equivalent CO2 emissions. For identifying of the emission potentials and strategic approach correctly for national or international target, carbon metric method based on exergetic approach is developed particularly in the building sector. In this study, three different emission criteria considering examples of building taken references, isolation, non-isolated conditions and TS-825 standard, were examined depending on exergetic analysis for building dispersion of Turkey. According to analyses, differences among emission criteria were found significant value with reaching 90%. At the end of the study, some assessment and recommendations about benefits of carbon emissions metric and importance of the exergy concept for building analyses have been made. © Springer International Publishing AG, part of Springer Nature 2018.
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    Benchmarking environmental impacts of power groups used in a designed UAV: Hybrid hydrogen fuel cell system versus lithium-polymer battery drive system
    (Elsevier Ltd, 2023) Çalışır, Duran; Ekici, Selçuk; Midilli, Adnan; Karakoç, T. Hikmet
    This study investigates the environmental impacts of using two different power groups in a fixed-wing Unmanned Aerial Vehicle (UAV). The first power group consists of a conventional electric motor, a lithium polymer battery and a propeller. The second power group is the hybrid power group formed by adding the Proton Exchange Membrane (PEM) fuel cell. The life cycle assessment (LCA) method is applied to the configurations to reveal environmental impact values (global warming, terrestrial ecotoxicity, photochemical oxidation, acidification, eutrophication and so on). Inventory and impact analysis calculations are performed using SimaPro 9.1 software. Ecoinvent 3.6 database is employed in this software. The environmental impact assessment is made according to CML-IA Baseline and ReCiPe method. In addition, the research involves hotspot analyses for both power group configurations. Consequently, the following is noticed as a result of a transition from lithium-polymer power group to hybrid hydrogen fuel cell system; (i) the global warming reduces by 6.95%, (ii) the terrestrial ecotoxicity reduces by 6.35%, (iii) the photochemical oxidation decreases by 1.23%, and (iv) the ozone layer depletion increases by 12.44%. These days when environmental problems stand out, the effects of UAVs hybridized with fuel cells, known as a clean energy source, related with environmental problems reflect the principal of this research.
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    Design and analysis of an IoT enabled unmanned aerial vehicle to monitor carbon monoxide: Methodology and application
    (Inderscience Publishers, 2023) Küçükkör, Özge; Aras, Orhan; Özbek, Emre; Ekici, Selçuk; Karakoç, T. Hikmet
    SciVal Topics Metrics Abstract Unmanned aerial vehicles (UAVs) are efficient platforms for the inspection and detection of hazardous particle emission locations in terms of cost and ability to reach challenging areas. In this study, a custom quadcopter UAV with metal oxide semiconductor (MOS) type carbon monoxide (CO) sensor and data acquisition module is designed to detect and measure CO pollution over industrial sites and urban areas. Unlike similar studies, a rope hanging design is used for sensor extension and collected data transmitted to the cloud using internet of things (IoT) technology. Flight tests are conducted to collect measurements over an area with a controlled fire to replicate industrial chimneys. CO readings on 26 data points result in between 0 and 4 PPM concerning their distance to the pollution zone. Therefore, a heatmap is created using real-time GPS locations and measured CO concentrations. Challenges in this operation are explained to guide future researchers and entrepreneurs.
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    Past and current components-based detailing of particle image velocimetry: A comprehensive review
    (Elsevier Ltd, 2023) Rohacs, Daniel; Yaşar, Onur; Kale, Utku; Ekici, Selçuk; Yalçın, Enver; Midilli, Adnan; Karakoç, T. Hikmet
    Particle image velocimetry has been widely used in various sectors from the automotive to aviation, research, and development, energy, medical, turbines, reactors, electronics, education, refrigeration for flow characterization and investigation. In this study, articles examined in open literature containing the particle image velocimetry techniques are reviewed in terms of components, lasers, cameras, lenses, tracers, computers, synchronizers, and seeders. The results of the evaluation are categorized and explained within the tables and figures. It is anticipated that this paper will be a starting point for researchers willing to study in this area and industrial companies willing to include PIV experimenting in their portfolios. In addition, the study shows in detail the advantages and disadvantages of past and current technologies, which technologies in existing PIV laboratories can be renewed, and which components are used in the PIV laboratories to be installed.
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    Reducing the fuel consumption and emissions with the use of an external fuel cell hybrid power unit for electric taxiing at airports
    (Elsevier Ltd, 2022) Keçeci, Mustafa; Colpan, C. Ozgur; Karakoç, T. Hikmet
    Airport ground operations have a great impact on the environment. Various innovative solutions have been proposed for aircraft to perform taxi movements by deactivating their main engines. Although these solutions are environmentally beneficial, onboard and external electric taxiing solutions that are actively used and planned to be used in airports are not completely carbon-free. The disadvantages of the existing solutions can be alleviated by using an external fuel cell hybrid power unit to meet the energy required for taxiing that does not put additional weight on the aircraft. To reveal the power and energy required by the system, Airbus A320-200, which is a narrow-body aircraft and frequently used in airports, has been considered in this study. To determine the physical requirements of the aircraft for taxiing, a total of 900 s taxi-out movement consisting of four different periods with different runway slope, headwind, and maximum speeds were examined. According to the determined physical requirements, the conceptual design of the proposed fuel cell battery system was created and the physical data of the system for each period were obtained using the Matlab Simulink environment. As a result of the simulation, it is seen that the system consumes approximately 1.96 g of hydrogen per second. In addition, it has been calculated that 578.34 kg of CO2 is emitted during the taxi-out movement. The results also show that as a result of using the proposed system, approximately 14.6 million tons of CO2 emission per year can be prevented.