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Öğe A FUZZY QFD-BASED APPROACH FOR CUTTING MACHINE SELECTION IN THE FURNITURE INDUSTRY(Bursa Uludağ Üniversitesi, 2025) İnce, Melike Nur; Taşdemir, Çağatay; Yildiz, AytaçTo survive in an increasingly competitive business environment, companies are placing a greater emphasis on customer demands. Demand-driven manufacturing has become a key business priority in light of these developments. Furthermore, customer demand has emerged as a pivotal consideration in strategic decision-making processes within the business sector. Adopting a customeroriented approach to decision-making in various operational areas, including purchasing, logistics, and production, could increase business profitability. In this study, a fuzzy AHP-based fuzzy QFD approach was developed for a cutting machine that a medium-sized furniture company sought to procure. This analysis identified eight customer requests and determined their relative importance using the Fuzzy AHP methodology. The results indicated that Precision (CR 3) was the most critical customer request, with a weight of 0.300, followed by Cutting Quality, which was identified as the second most crucial customer request, with a weight of 0.229. Subsequently, these weighted customer requests were input into the Fuzzy QFD methodology. Subsequently, ten technical requirements for machine selection were identified. The study results showed that the best-performing alternative was the laser cutting machine, with a percentage value of 28.00. In contrast, the worst-performing alternative was the autogenous flamecutting machine, with 19.40%. Although the employed methodology was explicitly focused on machine selection for metal components in the furniture industry, the findings offer significant insights with broader applicability. These insights provide a reference point for addressing complex decision-making problems of a similar nature, making the research valuable to practitioners and academics working in furniture manufacturing, machine selection, and multi-criteria decision-making.Öğe A Fuzzy TOPSIS and Interval Type-2 Fuzzy TOPSIS Based Approach for Sustainable Smart Supplier Selection(Abdulkadir KESKİN, 2025) Arslan, Beyza Betül; Karahan, Sıla Nurcan; Yildiz, AytaçIncreasing global competition and sustainability pressures have shifted supply chain management beyond a cost- and quality-oriented perspective. Today, firms are required to develop more holistic decision-making processes by incorporating environmental, social, and technological parameters. This study proposes an innovative supplier evaluation model that integrates sustainability principles with digital transformation dynamics. The model is structured around four main criterion groups: economic, environmental, technological, and operational. The criteria were determined through an extensive literature review and expert opinions from different sectors. In the analysis phase, two Multi-Criteria Decision-Making (MCDM) methods fuzzy TOPSIS and interval type-2 fuzzy TOPSIS were employed. The findings indicate that both methods identified the same supplier as the most suitable alternative. However, the interval type-2 fuzzy TOPSIS method provided a clearer differentiation among the alternatives, offering decision-makers a more reliable ranking under uncertainty. This demonstrates that type-2 fuzzy sets are more effective in environments characterized by high levels of uncertainty. As one of the few studies to apply both methods together, this research contributes to literature with a novel and comprehensive approach. Furthermore, the proposed model has the potential to guide decision-makers strategically, with applicability across diverse sectors and contexts.Öğe A Fuzzy TOPSIS Based Decision-Making Model for the Evaluation of Corporate Social Responsibility Projects(Fevzullah TEMURTAŞ, 2025) Arslan, Beyza Betül; Erbaş, Birgül; Yildiz, AytaçAbstract: Corporate social responsibility (CSR) is a concept that has gained increasing importance in recent years and represents individuals and organizations that conduct their activities with awareness of their social, cultural, economic, and environmental responsibilities. Organizations undertake various projects to provide social benefits, but the cost-benefit balance of these projects must be evaluated to ensure the efficient use of limited resources. Because this process involves a complex decision-making problem involving numerous criteria and uncertainties, multi-criteria decision-making methods that can model uncertainties more realistically contribute significantly to the process. In this study, the fuzzy TOPSIS method was used to evaluate CSR projects planned for implementation by a district municipality. Based on a literature review and expert opinions, a decision model was created by identifying ten evaluation criteria and seven alternative projects encompassing the economic, social, environmental, and governance dimensions of CSR. The results indicated that a project aimed at strengthening women's roles in social and economic life through women's cooperatives was prioritized. However, a project based on accessibility but weak sustainability and stakeholder engagement was ranked last. These results highlight the importance of considering social contribution, economic development, and sustainable development goals in the evaluation of CSR projects.Öğe A Hybrid Fuzzy AHP–TOPSIS Approach for Ranking Sustainable Green Technology Innovations(Fevzullah TEMURTAŞ, 2025) Doğanay, Kadriye; Yildiz, AytaçToday, environmental sustainability has become a strategic necessity in the face of global challenges such as climate change, depletion of natural resources, and rising carbon emissions. In this context, green technology innovations play a critical role in developing environmentally friendly production processes, enhancing energy efficiency, and supporting sustainable development goals. However, accurately assessing the performance of these technologies requires a multidimensional and uncertainty-based decision-making framework. In this study, a model based on a hybrid Fuzzy AHP–Fuzzy TOPSIS approach was developed to evaluate the performance of green technology innovations. In the first stage, ten main criteria were identified and pairwise compared by three experts, and the criterion weights were calculated using the Fuzzy Analytic Hierarchy Process (Fuzzy AHP). In the second stage, these weights were integrated into the Fuzzy TOPSIS method to rank nine alternative green technology innovations according to their closeness coefficients. The findings reveal that, when environmental, technological, and economic dimensions are jointly considered, green hydrogen, carbon capture, and energy-efficient coding technologies achieve the highest performance values. The proposed hybrid model provides a reliable and flexible methodological framework for guiding sustainable technology investments and designing green transformation policies.Öğe Assessment of Climate Change Factors and Impacts Using the Pythagorean Fuzzy AHP Approach(Amasya University, 2025) Aydın, Buse; Yildiz, AytaçToday, climate change has become a global crisis threatening not only the environment but also economic, social, and political systems worldwide. This situation necessitates the systematic analysis of both the drivers contributing to climate change and the areas affected by it. Given the high level of uncertainty in environmental decision-making processes, the use of fuzzy logic-based multi-criteria decision-making approaches has become essential. In this study, the Pythagorean Fuzzy Analytic Hierarchy Process (AHP), developed by utilizing Pythagorean fuzzy sets, is applied to prioritize the factors influencing climate change and the elements impacted by it. Accordingly, the relevant factors and elements were identified through literature review and expert opinions, and the methodological steps were followed to assign their respective weights. The results of the study indicate that among the factors contributing to climate change, fossil fuel use and carbon emissions was identified as the most critical factor. This was followed by animals and industrialization, while tourism activities and the health sector received the lowest priority levels. On the other hand, among the elements affected by climate change, biodiversity emerged as the most critical domain, with natural disasters and insects also assigned high importance levels. In contrast, destruction of cultural and historical sites and economy and socio-politics were ranked lower due to their more indirect effects. This study is the first to examine climate change drivers and impacts, ranking them under uncertainty. The findings provide decision-makers with a roadmap to identify strategic focal points in combating climate change.Öğe Determination of the best hydrogen production method in Türkiye by using neutrosophic picture fuzzy TOPSIS(Springer Science and Business Media B.V., 2024) Işık, Gurkan; Parlak, İsmail Enes; Yildiz, AytaçTo meet all energy requirements by renewable energy (RE) sources, hydrogen is an effective energy transport and storage instrument. Because of being a highly innovative field in developing countries, there are high uncertainties with different subcomponents in the hydrogen energy (HE) field. In the literature, fuzzy set extensions are heavily preferred to model different types of uncertainties when making decisions in the energy field. As one of the most comprehensive ones, spherical fuzzy set (SFS) is used to model the uncertainties caused by refusal and inconsistency within some theoretical limitations. In this study, a novel fuzzy set (FS) extension called neutrosophic picture fuzzy set has been developed to obtain a more flexible and reliable modeling approach usable with the information having higher inconsistency, and suitable with the problems requiring precise calculations. As a popular decision-making (DM) techniques, TOPSIS methodology has been redesigned based on neutrosophic picture fuzzy set. By using the developed methodology, the available hydrogen production (HP) alternatives of Türkiye have been evaluated. Biomass gasification (BG) has been decided as the best hydrogen energy production method under the current conditions. The results have been compared with the results obtained by spherical fuzzy TOPSIS and it has been proved that more reliable results are obtained by the proposed method. © The Author(s), under exclusive licence to Springer Nature B.V. 2023.Öğe Determining critical factors for the success of machine learning libraries considering fuzzy interrelationships(Pamukkale Üniversitesi, 2026) Parlak, İsmail Enes; Çelik, Miraç Tuba; Işık, Gürkan; Yildiz, AytaçAdvances in Machine Learning have led to groundbreaking developments across various fields. A key driver of this progress is the growing capabilities of machine learning libraries. However, these libraries still face certain limitations, which can hinder their application in some areas. In particular, developers often need to integrate their solutions across different libraries, languages, and platforms, which can reduce the effectiveness of machine learning applications. This study examines the direct and indirect impacts of various factors on the success of machine learning libraries, leveraging expert evaluations. Focusing on critical factors that shape library development based on user experiences is crucial. This approach ensures strategic advancement and optimizes energy and resource use. Given that many of these factors involve human perception-related uncertainties, the methodology incorporates a fuzzy linguistic approach with z-numbers to address the inherent vagueness. The findings reveal that considering the interrelationships among factors significantly alters their importance, as it accounts for both direct and indirect influences. Moreover, these interrelationships highlight which factors should be strategically prioritized, as improvements in one factor can drive improvements in others. The results obtained can support guiding the community developing artificial intelligence libraries toward the right objectives and formulating effective strategies to ensure the sustainability of artificial intelligence transformation.Öğe EVALUATION OF POTENTIAL HYDROGEN PRODUCTION METHODS IN TURKEY BY USING A HYBRID METHOD BASED ON PYTHAGOREAN FUZZY AHP AND INTERVAL TYPE-2 FUZZY TOPSIS(International Association for Hydrogen Energy, IAHE, 2022) Yildiz, Aytaç; Demi?r, Yunus; Işık, GurkanHydrogen is a promising energy storage and generation alternative to ensure that renewable energy sources are available to meet all energy needs in the long term. Many factors should be considered for sustainability of the environment while designing a hydrogen supply chain which consists of different production, storage, and transportation methods. Hydrogen energy is a new and innovative area especially for developing countries, so there can be high uncertainty during the decision process because of lack of expertness. In this study, available hydrogen production alternatives of Turkey are evaluated by using an integrated Pythagorean fuzzy AHP and interval type-2 fuzzy TOPSIS based methodology by considering technical, economic, environmental, and social aspects. © 2022 Proceedings of WHEC 2022 - 23rd World Hydrogen Energy Conference: Bridging Continents by H2. All rights reserved.Öğe SELECTION OF SOCKS EXPORT MARKETS FOR TURKEY USING MULTICRITERIA DECISION MAKING METHODS(Yildiz Technical University, 2020) Yildiz, Aytaç; Özbek, AhmetExport provides foreign exchange inflow and reduces unemployment and is, therefore, an important field of economic activity promoted by every country. Turkey is the sixth-largest exporter in the socks industry, which is a strategic export product. In this context, it wants to take first place by increasing its export volume. For this, it must choose the markets which will export well. However, there are many criteria that are effective in selecting the export market place and are independent of exporting countries. It is beneficial to use multicriteria decision-making (MCDM) methods in the solution of such problems. The aim of this study is to select the most suitable export market to increase Turkey’s socks export volume. Firstly, a survey of export market selection criteria is developed based on a literature review. The survey is completed by export specialists of socks exporting companies in Turkey to determine the most important criteria in the selection of socks export markets. Afterward, between 2014-2018 criterion data of the top 11 countries accounting for 70 percent of the world's total socks imports are derived from the Trade Map Database. 2020 values were obtained using regression analysis. TOPSIS (Technique for Order-Preference by Similarity to Ideal Solution), GRA (Grey Relational Analysis) and ANP (Analytical Network Process) methods are used to evaluate the alternative socks export markets. Sensitivity analysis is performed using TOPSIS, GRA and ANP data. The results are compared to select the best export market for the Turkish socks industry. © 2020 Yildiz Technical University.
