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Article Innovative 3d Modeling of an Old Oil Field for Sustainable Production: Case Study of Katin-Barbes Oil Field (kbof), Se Anatolia- Turkey(Elsevier Sci Ltd, 2023) Ozer, Zafer; Kamaci, Zuheyr; Aydemir, AttilaThe goal of this study is to establish a workflow for the re-interpretation of almost depleted fields targeting the long-term sustainable oil production; in particular, for the oil fields in Turkey and the neighboring Middle Eastern countries located on the fold and thrust belts of the Zagros Mountains. It also fills some of the gaps in our understanding of the northern part of the Arabian Platform by describing the seismic characteristics of the Cretaceous reservoirs that were deposited during the Aptian to Turonian. The Katin-Barbes oil field (KBOF) in SETurkey was used as a case study. In this area, 3D seismic data were used for structural interpretation and remodeling of Cretaceous carbonates sedimented in the complex tectonic region. The well logs from 55 wells in the field were used to create a compilation of formation tops and were used as reference points for two separate sets of 3-D seismic data, acquired in 1991 and 2017. The quality of seismic data was improved with interpretation filters. The structural model was obtained by using various qualifiers from the seismic cubes and seismic facies changes were identified by analyzing a number of seismic attributes. Therefore, seismic data and velocities from the borehole measurements were combined to form a velocity model in building a structural model. Seismic attributes and well logs were used to create a porosity model. Consequently, top and base of two reservoir units; the Derdere and Sabunsuyu Formations have been clarified and re-defined, and potential new well locations were identified. Depending on the results of this investigation, 9 new wells were drilled in the potential areas in the KBOF, recently. Except the last one drilled on the NE boundary of the northern block, all wells have been completed as the "oil producing wells" and top of the reservoir units were encountered at almost the same depths in our depth model. Therefore, results and proposed methods in this research are confirmed by the real, borehole data. This research will be an examplary study for the re-evaluation of older and/or almost depleted oil fields, either in Turkey or in the other Middle Eastern countries.Conference Object Citation - WoS: 90Citation - Scopus: 107Modeling and Sensitivity Analysis of High Temperature Pem Fuel Cells by Using Comsol Multiphysics(Pergamon-elsevier Science Ltd, 2016) Sezgin, Berna; Caglayan, Dilara Gulcin; Devrim, Yilser; Steenberg, Thomas; Eroglu, InciThe objective of this study is to observe the effect of the critical design parameters, velocities of inlet gases (hydrogen and air) and the conductivity of polymer membrane, on the performance of a high temperature PEM fuel cell. A consistent and systematic mathematical model is developed in order to study the effect of these parameters. The model is applied to an isothermal, steady state, three-dimensional PEM fuel cell in order to observe concentration profiles, current density profiles and polarization curves. The model includes the transport of gases in anode and cathode gas flow channels, diffusion in the catalyst layers, the transport of water and hydronium ion in the polymer electrolyte and in the catalyst layers, and the transport of electrical current in the solid phase. The model is considered as having a single flow channel. The simulation is performed by using licensed Comsol Multiphysics 5.0, Fuel Cells &Batteries Module. The results compare well with the experimental polarization data obtained at 160 degrees C for ohmic and activation regions. The best match with the experimental data is obtained when the inlet hydrogen gas velocity is 0.133 m/s whereas inlet air velocity is 1.3 m/s for proton conductivity of 10 S/m. (C) 2016 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.Conference Object Citation - WoS: 44Citation - Scopus: 56Three-Dimensional Modeling of a High Temperature Polymer Electrolyte Membrane Fuel Cell at Different Operation Temperatures(Pergamon-elsevier Science Ltd, 2016) Caglayan, Dilara Gulcin; Sezgin, Berna; Devrim, Yilser; Eroglu, InciA three-dimensional model for a high temperature polymer electrolyte membrane (PEM) fuel cell having an active area of 25 cm(2) is developed. Triple mixed serpentine flow channel single cell with phosphoric acid doped polybenzimidazole (FBI) membrane is used in the model. Steady-state, isothermal, single phase assumptions are defined for the system. The model is simulated at different temperatures ranging from 100 to 180 degrees C to investigate the influence of operation temperature on the performance of the cell. It is seen that there is an improvement in the performance of the cell as the operation temperature increases. Experimental data are used to validate the model both for single channel and triple mixed serpentine flow channel. Current density distribution is obtained at different operating voltages. The predicted results show that at high operating voltages the local current density is almost uniform; whereas, decreasing operating voltage causes non-uniformities in the local current density. (C) 2016 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.Conference Object Citation - Scopus: 8Simulation-Based Environments for Surgical Practice(Institute of Electrical and Electronics Engineers Inc., 2017) Dalveren,G.G.M.; Çağıltay,N.E.; Özçelik,E.; Maraş,H.Modeling and simulation environments provide several insights about the real situations such as endoscopic surgery. Endoscopic surgery requires both hand skills, so, understanding the effect of using dominant or non dominant hand on mental workload is important to better design, develop and implement modeling and simulation environments to support real-life implementations of surgical procedures. This experimental study presents a simulation application of eye-tracking approach to understand mental workload in different hand conditions: dominant hand, non-dominant hand and both hand. The results of the study show that, performing simulated surgical tasks by both hands compared to dominant hand, increases mental workload which is evident by higher pupil size. Accordingly, to manage the mental-load problems of surgeons while performing complex tasks that require both hand usage simulation-based environments can be used. Consequently, collection of detailed information such as eye-data, can give several insights about the behaviors of the surgeons. Also, their required skills can be improved by development of simulation and training environments. © 2017 IEEE.Conference Object Citation - WoS: 6Simulation-Based Environments for Surgical Practice(Ieee, 2017) Dalveren, Gonca Gokce Menekse; Cagiltay, Nergiz Ercil; Ozcelik, Erol; Maras, HakanModeling and simulation environments provide several insights about the real situations such as endoscopic surgery. Endoscopic surgery requires both hand skills, so, understanding the effect of using dominant or non dominant hand on mental workload is important to better design, develop and implement modeling and simulation environments to support real-life implementations of surgical procedures. This experimental study presents a simulation application of eye-tracking approach to understand mental workload in different hand conditions: dominant hand, non-dominant hand and both hand. The results of the study show that, performing simulated surgical tasks by both hands compared to dominant hand, increases mental workload which is evident by higher pupil size. Accordingly, to manage the mental-load problems of surgeons while performing complex tasks that require both hand usage simulation-based environments can be used. Consequently, collection of detailed information such as eye-data, can give several insights about the behaviors of the surgeons. Also, their required skills can be improved by development of simulation and training environments.Article Citation - WoS: 3Citation - Scopus: 8Assessing Software Quality Using the Markov Decision Processes(Wiley-blackwell, 2014) Korkmaz, Omer; Akman, Ibrahim; Ostrovska, SofiyaQuality of software is one of the most critical concerns in software system development, and many products fail to meet the quality objectives when constructed initially. Software quality is highly affected by the development process's actual dynamics. This article proposes the use of the Markov decision process (MDP) for the assessment of software quality because MDP is a useful technique to abstract the model of dynamics of the development process and to test its impact on quality. Additionally, the MDP modeling of the dynamics leads to early prediction of the quality, from the design phases all the way through the different stages of development. The proposed approach is based on the stochastic nature of the software development process, including project architecture, construction strategy of Software Quality Assurance system, its qualification actions, and team assignment strategy. It accepts these factors as inputs, generating a relative quality degree as an output. The proposed approach has been demonstrated for the design phase with a case study taken from the literature. The results prove its robustness and capability to identify appropriate policies in terms of quality, cost, and time. (c) 2011 Wiley Periodicals, Inc.Conference Object Citation - WoS: 58Citation - Scopus: 62Energy and Exergy Performance Assessments of a High Temperature-Proton Exchange Membrane Fuel Cell Based Integrated Cogeneration System(Pergamon-elsevier Science Ltd, 2020) Nalbant, Yagmur; Colpan, C. Ozgur; Devrim, YilserHigh-temperature proton exchange membrane fuel cell (HT-PEMFC), which operates between 160 degrees C and 200 degrees C, is considered to be a promising technology, especially for cogeneration applications. In this study, a mathematical model of a natural gas fed integrated energy system based on HT-PEMFC is first developed using the principles of electrochemistry and thermodynamics (including energy and exergy analyses). The effects of some key operating parameters (e.g., steam-to-carbon ratio, HT-PEMFC operating temperature, and anode stoichiometric ratio) on the system performance (electrical, cogeneration, and exergetic efficiencies) are examined. The exergy destruction rates of each component in the integrated system are found for different values of these parameters. The results show that the most influential parameter which affects the performance of the integrated system is the anode stoichiometric ratio. For the baseline conditions, when the anode stoichiometric ratio increases from 1.2 to 2, the electrical, cogeneration, and exergetic efficiencies decrease by 42.04%, 33.15%, and 37.39%, respectively. The highest electrical power output of the system is obtained when the SCR, operating temperature, and anode stoichiometric ratio are taken as 2, 160 degrees C, and 1.2, respectively. For this case, the electrical, cogeneration, and exergetic efficiencies are found as 26.20%, 70.34%, and 26.74%, respectively. (C) 2019 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.Conference Object Citation - WoS: 34Citation - Scopus: 39Development of a One-Dimensional and Semi-Empirical Model for a High Temperature Proton Exchange Membrane Fuel Cell(Pergamon-elsevier Science Ltd, 2018) Nalbant, Yagmur; Colpan, C. Ozgur; Devrim, YilserHigh temperature proton exchange membrane fuel cells (HT-PEMFC), which operate between 160 degrees C and 200 degrees C, can be generally used in portable and stationary power generation applications. In this study, a one-dimensional, semi-empirical, and steady-state model of a HT-PEMFC fed with a gas mixture consisting of hydrogen and carbon monoxide is developed. Some modeling parameters are adjusted using empirical data, which are obtained conducting experiments on a HT-PEMFC for different values of Pt loading and cell temperature. For adjusting these parameters, the total summation of the square of the difference between the cell voltages found using the experimental and theoretical methods is minimized using genetic algorithm. After finding the values of the adjusted parameters, the effects of different cell temperature, Pt loading, phosphoric acid (PA) percentage, and different binders (PBI and PVDF) on the performance of the fuel cell are examined. It was found that, the performance of the fuel cell using PVDF binder exhibited better performance as compared to that using PBI binder. (c) 2017 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.
