Browsing by Author "Aytekin, Ahmet"

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Citation Count: 1
Determining the factors affecting transportation demand management and selecting the best strategy: A case study
(Elsevier Sci Ltd, 2024) Görçün, Ömer Faruk; Korucuk, Selcuk; Gorcun, Omer Faruk
Demand management in transportation services, as well as demand sustainability, demand planning, and demand implementation are critical components in service quality and environmental sustainability. It is evident that developing a transportation system, particularly one responsive to society's aspirations and demands, will result in long-term and sustainable success for enterprises. Transportation demand management and strategies can produce alternative perspectives at a desirable and sufficient level to handle problems in the field while considering the obstacles. Considering the elements influencing transportation demand management in logistics enterprises, this study aims to evaluate factors affecting transportation demand management and select the best strategy. The study was carried out on logistic firms with a corporate identity in the Turkish province of Samsun (Turkiye), engaged in international transportation activities to define the criteria affecting transportation demand management and select the best transportation demand strategy. The constituents from the literature review were analyzed using the q-rung orthopair fuzzy MCDA methodology. "Freight Transportation" was determined to be the most crucial measure affecting transportation demand management, while "Competition Legislation and Regulations Regulation" was the least important factor. The rapid expansion in the number of companies participating in freight transport and their capacity was evaluated as the essential aspect for the relevant logistics companies in transport demand management. The "Strategy for Prioritizing High Occupancy Vehicles" is the best transportation strategy based on the weights of the transportation demand management factors. Because of the implementation of this strategy in logistics organizations, this study is regarded as a significant indicator of competitiveness to ensure efficiency and effectiveness. The defined transport demand strategy also represents an exemplary model of the measures that need to be developed to increase the demand preference for sustainable transport.
Citation Count: 13
Evaluating and selecting sustainable logistics service providers for medical waste disposal treatment in the healthcare industry
(Elsevier Sci Ltd, 2023) Görçün, Ömer Faruk; Aytekin, Ahmet; Korucuk, Selcuk; Tirkolaee, Erfan Babaee
Health institutes are structurally growing depending on the population increase and escalating demands for health services. As a negative result, the health industry produces more healthcare waste daily. Its efforts and resources cannot be sufficient to dispose of such medical wastes as the quantity and variety continue to increase. Therefore, developing solution partnership relations with logistics service providers specialized in collecting, storing, and disposing healthcare waste may be a beneficial and fruitful step for solving this problem. However, the evaluation and selection of service suppliers for healthcare waste disposal may not always result in success. Hence, the present work develops a robust integrated methodology on the basis of Step-wise Weight Assessment Ratio Analysis (SWARA) and COmplex PRoportional ASsessment (COPRAS) techniques based on Interval-Valued Fermatean Fuzzy Sets (IVFFSs) for healthcare decision-makers to make more rational and optimal decisions concerning service supplier selection. The proposed model based on the IVFFSs can also overcome incredibly complicated uncertainties in the assessment processes. A large-scale international hospital chain in Turkey is investigated using the developed methodology to find reasonable and logical solutions to assess and select the best Medical Waste Disposal and Logistics (MWDL) firm. It is revealed that the most important criterion is Storage Conditions where Republic Services, Inc is the most successful supplier of MWDL. Finally, theoretical and practical implications are discussed in detail in order to provide useful managerial insights and decision aids to assist in improving the sustainability of healthcare industry.
Citation Count: 0
Evaluation of Industry 4.0 strategies for digital transformation in the automotive manufacturing industry using an integrated fuzzy decision-making model
(Elsevier Sci Ltd, 2024) Görçün, Ömer Faruk; Mishra, Arunodaya Raj; Aytekin, Ahmet; Simic, Vladimir; Korucuk, Selcuk
The current paper proposes a methodological frame to identify the best Industry 4.0 (I4) strategy for the automotive manufacturing industry as a roadmap for companies to make a more straightforward digital transformation. We noticed a critical research gap when we performed an extensive literature review. Although there are many studies available that assess the readiness of companies for I4, only a few deal with decision -making in terms of sustainable development, and none have applied that to the automotive industry. Practitioners can apply the proposed model to determine the strategy based on technological developments in I4. The current paper proposes an extended version of the combined compromise solution approach with the help of the picture fuzzy sets. According to the paper 's results, by using the proposed model, developing a new business model based on technological improvements is the best strategy for the digital transformation of the automotive industry. Also, the lack of research and development implementations on I4 implementation is the most influential factor. Hence, practitioners in the automotive industry know the significance of research and development in reaching successful results for digital transformation. The acquired outcomes of the paper show that developing technology -based new business models is the best strategy for the automotive manufacturing industry concerning digital transformation instead of accommodating traditional business models and high technology utilization.
Citation Count: 16
Evaluation of the pharmaceutical distribution and warehousing companies through an integrated Fermatean fuzzy entropy-WASPAS approach
(Emerald Group Publishing Ltd, 2022) Görçün, Ömer Faruk; Gorcun, Omer Faruk; Ecer, Fatih; Pamucar, Dragan; Karama, Caglar
Purpose Pharmaceutical supply chains (PSCs) need a well-operating and faultless logistics system to successfully store and distribute their medicines. Hospitals, health institutes, and pharmacies must maintain extra stock to respond requirements of the patients. Nevertheless, there is an inverse correlation between the level of medicine stock and logistics service level. The high stock level held by health institutions indicates that we have not sufficiently excellent logistics systems presently. As such, selecting appropriate logistics service providers (drug distributors) is crucial and strategic for PSCs. However, this is difficult for decision-makers, as highly complex situations and conflicting criteria influence such evaluation processes. So, a robust, applicable, and strong methodological frame is required to solve these decision-making problems. Design/methodology/approach To achieve this challenging issue, the authors develop and apply an integrated entropy-WASPAS methodology with Fermatean fuzzy sets for the first time in the literature. The evaluation process takes place in two stages, as in traditional multi-criteria problems. In the first stage, the importance levels of the criteria are determined by the FF-entropy method. Afterwards, the FF-WASPAS approach ranks the alternatives. Findings The feasibility of the proposed model is also supported by a case study where six companies are evaluated comprehensively regarding ten criteria. Herewith, total warehouse capacity, number of refrigerated vehicles, and personnel are the top three criteria that significantly influence the evaluation of pharmaceutical distribution and warehousing companies. Further, a comprehensive sensitivity analysis proves the robustness and effectiveness of the proposed approach. Practical implications The proposed multi-attribute decision model quantitatively aids managers in selecting logistics service providers considering imprecisions in the multi-criteria decision-making process. Originality/value A new model has been developed to present a sound mathematical model for selecting logistics service providers consisting of Fermatean fuzzy entropy and WASPAS methods. The paper's main contribution is presenting a comprehensive and more robust model for the ex ante evaluation and ranking of providers.
Citation Count: 4
Foreign market selection of suppliers through a novel REF-Sort technique
(Emerald Group Publishing Ltd, 2022) Görçün, Ömer Faruk; Gorcun, Omer Faruk; Ecer, Fatih; Pamucar, Dragan; Karamasa, Caglar
Purpose The present study aims to provide a practical and robust assessment technique for assessing countries' investability in global supply chains to practitioners. Thus, the proposed approach can help decision-makers evaluate and select appropriate countries in the expansion process of the global supply chains and reduce risks concerning country (market) selection. Design/methodology/approach The present study proposes a novel decision-making approach, namely the REF-Sort technique. The proposed approach has many valuable contributions to the literature. First, it has an efficient basic algorithm and can be applied to solve highly complicated decision-making problems without requiring advanced mathematical knowledge. Besides, some characteristics differentiate REF-Sort apart from other techniques. REF-Sort employs the value or value range that reflects the most typical characteristic of the relevant class in assignment processes. The reference values in REF-Sort and center profiles are similar in this regard. On the other hand, class references can be defined as ranges in REF-Sort. Secondary values, called successors, can also be employed to assign a value to the appropriate class. REF-Sort can also determine the reference and successor values/ranges independently of the decision matrix. In addition, the proposed model is a maximally stable and consistent decision-making tool, as it is resistant to the rank reversal problem. Findings The current papers' findings indicate that countries have different features concerning investment. Hence, the current paper pointed out that only 22% of the 95 countries are investable, whereas 19% are risky. Thus, decision-makers should make detailed evaluations using robust, powerful, and practical decision-making tools to make more reasonable and logical decisions concerning country selection. Originality/value The current paper proposes a novel decision-making approach to evaluate. According to the authors' information, the proposed model has been applied to evaluate investable countries for the global supply chains for the first time.
Citation Count: 2
Fresh food supplier selection for global retail chains via bipolar neutrosophic methodology
(Elsevier Sci Ltd, 2023) Görçün, Ömer Faruk; Aytekin, Ahmet; Korucuk, Selcuk
Due to increases in world population, rapid urbanization, increasing environmental pollution, and poorly managed food supply chains (FSCs), supplying clean and reliable agri-food has become more critical. Furthermore, increasing concerns of the urban population on healthy and balanced nutrition have increased their demand for fresh foods (FFs). Also, the retail industry has become the leading sector responding to almost all requirements of individuals, including FFs. Heightened awareness of individuals on health, reliability, and quality forces retail chains to provide more qualified, sustainable, and reliable FFs for their customers. Retail chains try to construct and manage well-structured global fresh food supply chains (FFSCs) to respond to customers' needs satisfactorily. Thus, selecting logistics service providers performing FF logistics operations (i.e., cold transportation, warehousing, and other logistics activities) from farms to retailers is essential for reliable and sustainable FFSCs. Because FFSCs are pretty sensitive, and minor mistakes or delinquency may cause severe costs.Global retail chains, in particular, only focus on meeting short-term demand and not on a sustainable fresh food supplier selection; fresh food suppliers are essential to determine sustainability performance. In this context, a more holistic approach is needed, focusing not only on the global retail chain level's direct impacts but also on the positive impacts at the overall system level. While this study fills a gap, it also assesses the long-term and lasting impact of choosing a fresh food supplier.In addition, the impacts of logistics service providers on FFSCs' overall performance have not been addressed adequately in the relevant literature. This work aims to analyze the factors identified by the extended form of the Delphi method developed in the present article, influencing the selection of logistics service providers producing logistics services for fresh fruits and vegetables with the BN-VIKOR procedure. The paper's main significant finding is that the logistics firms' service capacity is the determinative and most influential factor. The current study provides insights and beneficial road maps to the practitioners and decision-makers in retailing industry to structure FFSCs. The results contribute to the literature on criteria for selecting sustainable fresh food suppliers in global retail chains and identify strategies and improvement opportunities that can lead to improvement in practice.
Citation Count: 0
Sustainability performance assessment of freight transportation modes using an integrated decision-making framework based on m-generalized q-neutrosophic sets
(Springer, 2024) Görçün, Ömer Faruk; Tirkolaee, Erfan Babaee; Aytekin, Ahmet; Korucuk, Selcuk
The freight transport industry is one of the primary sectors responsible for excessive energy consumption and greenhouse gas emissions. Restructuring international and domestic freight transport chains based on sustainability and green transportation is critical for practitioners and policymakers to reduce pressure on the logistics and transportation industries. This study aims to develop a mathematical model for selecting the most appropriate transportation type, and accordingly, the optimal route in transportation operations to improve the sustainability performance of the freight transportation industry. Therefore, the main goal is to choose the most suitable route and transportation type which contributes to create a more eco-friendly and sustainable transportation system. For this purpose, Neutrosophic Number-based Delphi (NN-Delphi), m-Generalized q-Neutrosophic Sets (mGqNSs)-based Stepwise Weight Assessment Ratio Analysis (MGqNS-SWARA) and mGqNSs-based Additive Ratio Assessment (mGqNS-ARAS) are developed and implemented to set the influential criteria, compute the weights of these criteria, and identify the sustainability performance of the freight mode variants, respectively. According to the final results, "Cargo security" and "Accident rates" are the most important criteria with a relative importance score of 0.0237, contributing to the sustainability of load transport modes. Moreover, "Maritime Transport Mode" is identified as the most sustainable transportation type with a relative importance score of 0.7895. Finally, it is revealed that there is a positive relationship between maritime transport and sustainability.
Citation Count: 3
Warehouse site selection for humanitarian relief organizations using an interval-valued fermatean fuzzy LOPCOW-RAFSI model
(Pergamon-elsevier Science Ltd, 2024) Görçün, Ömer Faruk; Aytekin, Ahmet; Gorcun, Ozhan; Simic, Vladimir; Gorcun, Omer Faruk
The selection of warehouse locations for humanitarian organizations represents a critical and strategic decisiomaking process. It is inherently complex, influenced by uncertainties and conflicting criteria. This study presents an integrated decision-making framework tailored to address this complexity for humanitarian organizations. The framework combined two key methodologies: logarithmic percentage change-driven objective weighting (LOPCOW) and ranking of alternatives through functional mapping of criterion sub-intervals into a single interval (RAFSI). Besides, this model has strengthened by extending with the help of the interval-valued Fermatean fuzzy sets to capture and process highly complex ambiguities. A significant advantage of this proposed model is its high resilience against the rank reversal problem, which is a critical shortcoming and challenge in decisionmaking methodologies. Additionally, the model boasts a robust, powerful, and practical structure coupled with a straightforward and easily understandable algorithm. Based on the results obtained through the implementation of the model, population density (0.1140) emerges as the most critical factor influencing decisions regarding site selection. Humanitarian organizations aim to rescue and assist as many individuals as possible during and after a disaster, prioritizing their humanitarian needs. Therefore, enhancing logistical efficiency in disaster zones and promptly reaching affected populations becomes feasible when humanitarian aid warehouses are as close as possible to areas with the highest concentration of potential disaster victims. Moreover, according to the study's findings, the most suitable option identified for the case study was Bagcilar. The conclusions drawn from sensitivity and comparative analyses affirm the model's reliability, consistency, and resilience.