Sürdürülebilir Kalkınma Amaçları
Yayınlar
- MakaleYalnız künye2021Towards a circular economy: Investigating the critical success factors for a blockchain-based solar photovoltaic energy ecosystem in Turkey
Erol, Ismail; Peker, Iskender; Ar, Ilker Murat; Turan, İsmet; Searcy, Cory
Novel business models can be implemented through digital platforms to enable better circular economy (CE) performance in the renewable energy industry. For example, blockchain can assist in developing innovative business models throughout the solar photovoltaic energy ecosystem (SPVEE) to improve CE. Ranked fifth in total installed photovoltaic (PV) capacity, Turkey, as a developing country, should take the necessary steps and make progress towards achieving CE in the SPVEE. The solar PV industry requires further innovation to address the negative environmental impact of existing linear business models. To ensure favorable results, identifying and evaluating critical success factors (CSFs) are necessary. However, no study has investigated CSFs for SPVEE or any other renewable energy source to achieve a blockchain-based infrastructure towards increased CE performance. Therefore, the goal of this study is to identify and examine the CSFs to improve the performance of a blockchain-based SPVEE towards CE in Turkey. To this end, first, the CSFs for blockchain-based SPVEE were identified through both a literature review and the Nominal Group Technique (NGT). Then, Intuitionistic Fuzzy (IF)-DEMATEL was used to explore their interrelationships based on the expert data. Finally, IF-DELPHI was employed to validate the results. Our findings suggested that effective government incentive programs and regulations are significant for blockchain-based SPVEE towards CE in Turkey. The findings of this study assist macro and micro decision-making in the potential implementation of blockchain in Turkish SPVEE to improve CE. They are also invaluable for other countries and can be used as a reference point.
- MakaleYalnız künye2020Evaluating the feasibility of blockchain in logistics operations: A decision framework
Ar, Ilker Murat; Erol, Ismail; Peker, Iskender; Ozdemir, Ali Ihsan; Medeni, Tunc Durmus; Medeni, Ihsan Tolga
The main purpose of this study is to investigate the feasibility of blockchain technology in logistics industry using a quantitative approach. To this end, a decision framework is proposed based on a multi-criteria decision structure that incorporates AHP into VIKOR under Intuitionistic Fuzzy Theory. This integration presents different solutions and rankings based on different decision-making strategies and also captures uncertainty in the evaluation process. While Intuitionistic Fuzzy AHP calculates the importance weights of the proposed criteria indicated as scalability, privacy, interoperability, audit, latency, visibility, trust, and security, Fuzzy VIKOR ranks the logistics operations demonstrated as materials handling, warehousing, order processing, transportation, packaging, fleet management, labeling, vehicle routing and product returns management. The proposed decision framework was applied in a large-scale logistics company located in Turkey. The findings of this study suggest that while the most important criteria are security, visibility and audit, the most feasible logistics operations proved to be transportation, materials handling, warehousing, order processing and fleet management in a possible blockchain implementation. The decision framework in this study may enable decision makers to evaluate the feasibility of blockchain in logistics operations, which is one of the main research gaps in the current blockchain research. Furthermore, this is the first study that integrates AHP and VIKOR methods under Intuitionistic Fuzzy Theory in the context of blockchain.
- BildiriYalnız künye2020Evaluation of home health care vehicle routing methods by intuitionistic fuzzy AHP
Peker, Iskender; Caybasi, Gokhan; Buyukozkan, Gulcin; Gocer, Fethullah; Kahraman, C.; Cevik Onar, S.; Oztaysi, B.; Sari, I.U.; Cebi, S.; Tolga, A.C.
In our country, Home Health Care (HHC) units support people who are fully bed-dependent in order to provide health services at the right time, place and conditions. Vehicle Routing Problem (VRP) is used for cost, speed and distance optimization in delivering products or services to customers. In addition, there will be improvements in HHC and it will also save on transportation, storage and labor costs by determining the most appropriate VRP’s solution methods. In this respect, the aim of this study is to determine the best VRP’s solution method which can increase the efficiency of HHC. The proposed approach is based on Intuitionistic Fuzzy Analytic Hierarchy Process (IF-AHP) method which is a strong technique for dealing with uncertainties. According to results, the most important criteria is “time based factors”. Meta-heuristic is the appropriate solution algorithms for VRP in HHC.
- MakaleYalnız künye2020The role of blockchain in reducing the impact of barriers to humanitarian supply chain management
Ozdemir, Ali Ihsan; Erol, Ismail; Ar, Ilker Murat; Peker, Iskender; Asgary, Ali; Medeni, Tunc Durmus; Medeni, Ihsan Tolga
Purpose: The objective of this study is to investigate the role of blockchain in reducing the impact of barriers to humanitarian supply chain management (HSCM) using a list of blockchain benefits. Design/methodology/approach: A decision aid was used to explore the suitability of blockchain in humanitarian supply chains. To achieve that, first, a list of barriers to HSCM was identified. Then, the intuitionistic fuzzy decision-making trial and evaluation laboratory (IF–DEMATEL) method was utilized to determine the relationships and the level of interdependencies among the criteria. Finally, the intuitionistic fuzzyanalytic network process (IF–ANP) technique was employed, as it successfully handles dependencies among the criteria. Findings: The findings of this study suggest that interorganizational barriers are the most suitable ones, the impacts of which blockchain may alleviate. This study further suggests that trust turned out to be the most significant benefit criterion for the analysis. Research limitations/implications: The readers should construe the findings of this study with caution since it was carried out using the data collected from the experts of a particular country. Moreover, the proposed decision aid contemplates a limited set of criteria to assess a possible role of blockchain in overcoming the barriers to HSCM. Practical implications: The findings of this study can assist humanitarian supply chain managers to make more judicious assessments on whether they implement the blockchain in humanitarian supply chain operations. Specifically, this research may help decision makers to identify the certain barriers, the impact of which may be reduced by using the blockchain. The findings of this research will also help various decision makers make more rational decisions and allocate their resources more effectively. Originality/value: To the best of authors’ knowledge, no single study exists to investigate the role of blockchain in reducing the impact of barriers to HSCM using an intuitionistic fuzzy multi-criteria decision-making approach.
- Derleme MakaleAçık Erişim2019Literature review on success factors and methods used in warehouse location selection
Gergin, Ramazan Eyup; Peker, Iskender
The fact that the production and consumption amounts are different from each other gives a dynamic feature to the concept of storage. In addition, an effective storage activity hinges upon the selection of the right warehouse location that takes into account capital and labor investments; minimizes the transportation cost and time. The aim of this study is to investigate the preliminary researches in the selection of the warehouse location selection and to present information on which success factors and methods are preferred. Within this scope, many academic studies have been examined by filtering various databases. According to the results of the study, the most used methods in warehouse location selection are multi-criteria decision making methods such as AHP, ANP and TOPSIS; and the most commonly used success factor is determined as the cost-based factors.
- BildiriAçık Erişim2019Firm Selection Based on Logistics Risk Factors: A Multiple Criteria Decision Making Approach
Peker, Iskender; Korucuk, Selcuk; Baki, Birdogan
Logistics firms are exposed several domestic and global risks such as variability in demand, shipment damages, earthquakes, and terrorist attacks. The purpose of this study is to provide an approach for selecting a logistics firm based on logistics risk factors according to the manufacturing firms' perspectives. An analytical network process method is utilized to determine risk factors' importance levels and VIKOR method is used to select the logistics firm. The study results show that the most important logistics risk factors are customer and supplier, and the least risky logistic firm is B. It can be concluded that the proposed model enables managers to examine potential risks influencing their logistics activities and select the logistics firm having minimum risk.
- MakaleYalnız künye2016Logistics center site selection by ANP/BOCR analysis: A case study of Turkey
Peker, Iskender; Baki, Birdogan; Tanyas, Mehmet; Murat Ar, Ilker
Site selection for logistics centers is one of the most strategic decisions in logistics. This study addresses the problem of logistics center site selection, using Analytic Network Process/Benefits, Opportunities, Costs and Risks, which is a multi-criteria decision making technique. The decision problem is applied to the city of Trabzon, which is an important city of the Eastern Black Sea Region in Turkey. First, the results are evaluated in terms of each sub-network and each group and, next, are consolidated for each alternative. They yield that Alternative A is the most appropriate logistics center location of all in Trabzon. Furthermore, the sensitivity analysis results emphasize that the decision model is robust.
- MakaleYalnız künye2015An integrated evaluation model for service quality of hospitals: A case study from Turkey
Baki, Birdogan; Peker, Iskender
In this paper, an integrated approach, in which Fuzzy Analytic Hierarchy Process (FAHP) and Fuzzy TOPSIS (FTOPSIS) is used, is proposed to rank the hospitals according to service quality from the patient's point of view. The FAHP is employed to determine the weights of service quality criteria for the hospitals, and FTOPSIS method is used to rank the hospitals. Empirical results show that when "reliability" is the most important criterion, "empathy" is the least important criterion in terms of hospital service quality. A sensitivity analysis is also applied to check how sensitive our model is to changes in the various criteria weights.