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Article Citation - Scopus: 41Determination of Key Performance Indicators for Measuring Airport Success: a Case Study in Libya(Elsevier Ltd, 2018) Eshtaiwi,M.; Badi,I.; Abdulshahed,A.; Erkan,T.E.Airports need to evaluate their performance and effectiveness periodically to determine whether objectives are being achieved and how their performance compares to similar best practices. The goals of this paper are twofold: First, to offer a list of essential airport key performance indicators (KPIs) that can provide decision makers in the Libyan airport industry a practical framework to measure and monitor performance over time. The second goal is to use the AHP technique to derive the weights of the KPIs and to select the best international airport in Libya based on the values of the KPIs at each airport according to the judgments of experts. However, the implementation steps of the AHP method will be simplified by using the Expert Choice software. The paper presents the importance weights of seventeen KPIs across five aspects of airport performance. As a result of this study, Libyan airports can benchmark their performance against others or through internal benchmarking. © 2017 Elsevier LtdArticle Citation - WoS: 2Citation - Scopus: 2Performance Assessment of Anion Exchange Electrolyzer With PBI-BASED Membrane Through 0-D Modeling(Elsevier Ltd, 2025) Celebi, Ceren; Colpan, C. Ozgur; Devrim, YilserAnion exchange membrane (AEM) water electrolysis is emerging as a promising method for the sustainable production of hydrogen. A key advantage lies in the potential for cost-effective hydrogen production by substituting expensive noble metal electrocatalysts with affordable transition metals. This work presents a 0-D mathematical model for evaluating the performance of AEMWEs, with a particular focus on polybenzimidazole (PBI)-based membranes, which are renowned for their high thermal stability, chemical resistance and excellent conductivity in alkaline media. The objective of the model is to predict the behavior of membranes in AEMWE systems, and it has been employed to evaluate the performance of a range of PBI membranes. To ensure precision, the values were meticulously selected from the literature, in accordance with the experimental conditions. Furthermore, IR-corrected validation was incorporated to isolate the impact of membrane conductivity on performance, thereby facilitating a dependable assessment of PBI membranes under diverse conditions. The model considers the effects of electrolyte resistance and bubble formation on cell voltage behavior. The efficiency was evaluated on the basis of the higher heating value (HHV). The findings demonstrate that one membrane exhibits consistent efficiency across a broad temperature range (40-90 degrees C), whereas the other displays notable variability under diverse conditions. In particular, the efficiency of the electrolyzer is significantly enhanced by the use of thinner membranes and higher temperatures. The highest efficiencies obtained were 83.9% and 79.8% for 25 mu m and 50 mu m PBI/Polystyrene membrane under the operating conditions of 1 M KOH solution at 80 degrees C and current density of 2 A/cm2. This study aims to provide valuable information on the performance of PBI membranes through a zero-dimensional model validated by experimental data.Article Citation - Scopus: 16New generation radiation-grafted PVDF-g-VBC based dual-fiber electrospun anion exchange membranes(Elsevier Ltd, 2024) Kırlıoğlu,A.C.; Rajabalizadeh Mojarrad,N.; Alkan Gürsel,S.; Güler,E.; Yarar Kaplan,B.Anion Exchange Membranes (AEM) have the potential to solve the cost issues of fuel cell technologies due to their basic environment that can allow the use of cheaper components. However, there is still a need to develop an ideal inexpensive, mechanically robust AEM with high ionic conductivity and ion exchange capacity (IEC). In this work, we present various dual-fiber electrospun membranes based on a novel radiation-grafted copolymer. First, the synthesis route of radiation-induced grafting of vinyl benzyl chloride (VBC) onto poly (vinylidene fluoride) (PVDF) to prepare PVDF-g-VBC was optimized. Then, PVDF-g-VBC powders were used to fabricate dual-fiber electrospun mats with inert PVDF and commercial Fumion-FAA-3 ionomer. Dual-fiber electrospun mats were hot-pressed and then quaternized with trimethylamine. Finally, mechanical properties, ion exchange capacity, ionic conductivity, and morphology of these prepared dual-fiber electrospun membranes were investigated. The dual-fiber membrane prepared with PVDF-g-VBC (88% of the total weight of the membrane) and PVDF: Fumion-FAA-3 (1:2) mix (12 wt%) realized ionic conductivity of 4.67 mS/cm at 25 °C, high ion exchange capacity of 1.35 mmol/g with Young's Modulus of 761 MPa. The membrane based on the combination of radiation grafting and dual-fiber electrospinning was prepared for the first time in literature and offers the prospect of tuning and fine-control of mechanical and physicochemical properties of AEMs. © 2023 Hydrogen Energy Publications LLCArticle Citation - Scopus: 35Assessment of Polybenzimidazole/Mof Composite Membranes for the Improvement of High-Temperature Pem Fuel Cell Performance(Elsevier Ltd, 2024) Devrim,Y.; Colpan,C.O.This study aims to determine the most effective utilization of ZIF-8 type metal-organic framework (MOF) doped polybenzimidazole (PBI) composite membrane in high-temperature polymer electrolyte membrane fuel cells (HT-PEMFC) and investigate how ZIF-8 filler affects performance. ZIF-8 particles were prepared by solvothermal method and added to the PBI polymer using a weight percentage varying from 1 to 5 %. XRD, BET, and TEM examined the prepared ZIF-8. Composite membrane properties were investigated by XRD, SEM analysis, proton conductivity measurements, acid doping, and acid stripping tests. The HT-PEMFC performances of the membranes were carried out using Hydrogen and dry air at 150–180. The highest performance was acquired with the composite ZIF8/PBI-2 membrane as 0.432 W/cm2 at 170 °C. The obtained result is explained by easier proton transfer over ZIF-8's enlarged tunnel network. This study proposes a promising strategy to use ZIF-8 to prepare a PBI composite membrane with excellent proton conductivity, acid doping, and low acid leaching for HT-PEMFC application. The current study's findings can support future research on PBI/MOF-based composite membranes for HT-PEMFC applications. © 2024 Hydrogen Energy Publications LLC
