The blood supply chain is an inseparable part of health systems. The importance of blood and the ... more The blood supply chain is an inseparable part of health systems. The importance of blood and the difficulties of managing the blood supply chain have led to numerous publications on this topic over the last two decades. This study seeks to reveal the state of the art of the blood supply chain and provide research gaps and future research directions. For this purpose, a mixed review methodology is conducted that includes bibliometric analysis, network analysis, and a six-dimension taxonomy. Bibliometric analysis identifies the most contributing journals, authors, and countries as well as provides popular keywords, while network analysis reveals interactions between these components. Taxonomy clarifies decision models and research gaps with a deeper examination. The electronic database Web of Science is examined to uncover relevant articles. In total, 265 articles are analyzed in detail. The findings reveal that the blood supply chain gathers more interest from researchers, and despit...
Journal of Ambient Intelligence and Smart Environments
People around the world have experienced fundamental transformations during mass events. The Indu... more People around the world have experienced fundamental transformations during mass events. The Industrial Revolution, World War II, and the collapse of the Berlin Wall are some of the cases that have caused radical societal changes. COVID-19 has also been a process of mass experiences regarding society. Determining the mass impact the pandemic has had on society shows that the pandemic is facilitating the transition to the so-called new normal. Istanbul is a multi-identity city where 16 million people have intensely experienced the pandemic’s impact. While determining the identities of cities in the world, one can see that different city structures provide different data sets. This study models a machine learning algorithm suitable for the data set we’ve determined for the 39 different districts of Istanbul and 82 different features of Istanbul. The aim of the study is to indicate the changing societal trends during the COVID-19 pandemic using machine learning techniques. Thus, this w...
The number of passengers in public transport has decreased significantly in major cities around t... more The number of passengers in public transport has decreased significantly in major cities around the world due to COVID-19. As residents of many countries work from home, they have avoided public transport to minimize their exposure to the outbreak and have changed their way of traveling within their cities due to major changes in local public transport services. Istanbul is one of the cities most affected by the pandemic in terms of the daily number of passengers using public transportation. For the first time since the pandemic started in Istanbul, the use of urban public transportation has decreased by more than 90 percent. The aim of this study is to examine the measures taken in Istanbul public transport in order to prevent the spread of the coronavirus pandemic. In addition, the trends in public transport and inter-modes demands during COVID-19 are analyzed. The results showed that COVID-19 measures to protect the health of passengers in Istanbul public transport are in line wi...
The epidemic disease emerged in Wuhan/China in December 2019, which primarily causes acute respir... more The epidemic disease emerged in Wuhan/China in December 2019, which primarily causes acute respiratory syndrome and spread worldwide in a very short time. Although the countries took numerous precautions, the spread of the virus could not be controlled. Furthermore, due to the inability to maintain physical distance and the excess of shared surfaces, public transport services also increase the risk of spreading. This study analyzes the changes in perceptions and behavior of passengers who use public transportation via a survey. The survey is developed to assess the behavioral change of passengers pre and post-pandemic of COVID-19. Outcomes showed a notable shift among transportation modes due to closure of venues, utilization of distance education, partial curfews in Istanbul. A further focal point of the study is the passengers’ attitudes towards preventive measures and their perceptions on how well responsible bodies have implemented the measures. Thus, it provides valuable insights into the changes in the traveling habits of city residents, which help the policymakers of public transportation.
Transportation Research Record: Journal of the Transportation Research Board
Health care systems throughout the world are under pressure as a result of COVID-19. It is over t... more Health care systems throughout the world are under pressure as a result of COVID-19. It is over two years since the first case was announced in China and health care providers are continuing to struggle with this fatal infectious disease in intensive care units and inpatient wards. Meanwhile, the burden of postponed routine medical procedures has become greater as the pandemic has progressed. We believe that establishing separate health care institutions for infected and non-infected patients would provide safer and better quality health care services. The aim of this study is to find the appropriate number and location of dedicated health care institutions which would only treat individuals infected by a pandemic during an outbreak. For this purpose, a decision-making framework including two multi-objective mixed-integer programming models is developed. At the strategic level, the locations of designated pandemic hospitals are optimized. At the tactical level, we determine the loca...
Environmental guidelines in the automotive industry greatly emphasize the recycling, remanufactur... more Environmental guidelines in the automotive industry greatly emphasize the recycling, remanufacturing, and recovering of end-of-life vehicles (ELVs). Given the principle of extended producer responsibility, developing an effective reverse logistics network is the most significant digit ahead of the industry. However, initial attempts addressing the reverse logistics network design (RLND) problem were short-sighted, focusing on cost minimization. Undoubtedly, the whole concept of recycling was founded on the pillars of sustainability. Accordingly, reverse logistics network design must be motivated by long-term environmental and societal benefits. This fact has become even more prominent in the current pandemic environment as COVID-19 has added serious uncertainties and risks to the supply chain processes. This paper reiterates the essence of sustainability goals and proposes a multi-objective fuzzy mathematical model to RLND problem for ELVs under such a fragile and fuzzy environment....
Abstract Energy has a crucial role for the existence and social well-being of human. Among variou... more Abstract Energy has a crucial role for the existence and social well-being of human. Among various options, hydrogen is the promising energy carrier for sustainable energy systems. As an important source of hydrogen, Hydrogen Sulphide (H2S) is abundantly found in Black Sea waters and known as an environmental pollutant. The main aim of this study is to evaluate Thermochemical, Electrochemical, Thermal, Photochemical, Plasma, and Thermal methods as decomposition methods, which meet sustainability aspects better than other technologies, based on expert opinions. As sustainable criteria, economically feasibility, ecologically feasibility, efficiency, process simplicity, energy requirement, safety and reliability, applicability and operational suitability and technical maturity are considered to determine the most appropriate hydrogen production method. In this sense, we have suggested a new integrated Multi-Criteria-Decision-Making (MCDM) methodology consisting of stepwise weight assessment ratio analysis (SWARA) with fuzzy set theory (FST) and Weighted Aggregated Sum Product Assessment (WASPAS) by employing interval valued intuitionistic fuzzy sets (IVIFS) in the selection process. The contribution of the study is not only proposing a new method which hybridizes the SWARA and WASPAS under uncertainty but also selecting the most sustainable Hydrogen production method utilizing from H2S in the Black Sea in Turkey, considering sustainable criteria which are unavoidable in energy management problems. At the end, the results are discussed, and sensitivity and comparative analyses are utilized to check the robustness and feasibility of solutions. Consequently, electrochemical is selected as the best and most appropriate hydrogen production method in terms of providing high efficiency in conversion and sustainable processes, i.e handling, transporting and storing harmful chemicals.
The blood supply chain is an inseparable part of health systems. The importance of blood and the ... more The blood supply chain is an inseparable part of health systems. The importance of blood and the difficulties of managing the blood supply chain have led to numerous publications on this topic over the last two decades. This study seeks to reveal the state of the art of the blood supply chain and provide research gaps and future research directions. For this purpose, a mixed review methodology is conducted that includes bibliometric analysis, network analysis, and a six-dimension taxonomy. Bibliometric analysis identifies the most contributing journals, authors, and countries as well as provides popular keywords, while network analysis reveals interactions between these components. Taxonomy clarifies decision models and research gaps with a deeper examination. The electronic database Web of Science is examined to uncover relevant articles. In total, 265 articles are analyzed in detail. The findings reveal that the blood supply chain gathers more interest from researchers, and despit...
Journal of Ambient Intelligence and Smart Environments
People around the world have experienced fundamental transformations during mass events. The Indu... more People around the world have experienced fundamental transformations during mass events. The Industrial Revolution, World War II, and the collapse of the Berlin Wall are some of the cases that have caused radical societal changes. COVID-19 has also been a process of mass experiences regarding society. Determining the mass impact the pandemic has had on society shows that the pandemic is facilitating the transition to the so-called new normal. Istanbul is a multi-identity city where 16 million people have intensely experienced the pandemic’s impact. While determining the identities of cities in the world, one can see that different city structures provide different data sets. This study models a machine learning algorithm suitable for the data set we’ve determined for the 39 different districts of Istanbul and 82 different features of Istanbul. The aim of the study is to indicate the changing societal trends during the COVID-19 pandemic using machine learning techniques. Thus, this w...
The number of passengers in public transport has decreased significantly in major cities around t... more The number of passengers in public transport has decreased significantly in major cities around the world due to COVID-19. As residents of many countries work from home, they have avoided public transport to minimize their exposure to the outbreak and have changed their way of traveling within their cities due to major changes in local public transport services. Istanbul is one of the cities most affected by the pandemic in terms of the daily number of passengers using public transportation. For the first time since the pandemic started in Istanbul, the use of urban public transportation has decreased by more than 90 percent. The aim of this study is to examine the measures taken in Istanbul public transport in order to prevent the spread of the coronavirus pandemic. In addition, the trends in public transport and inter-modes demands during COVID-19 are analyzed. The results showed that COVID-19 measures to protect the health of passengers in Istanbul public transport are in line wi...
The epidemic disease emerged in Wuhan/China in December 2019, which primarily causes acute respir... more The epidemic disease emerged in Wuhan/China in December 2019, which primarily causes acute respiratory syndrome and spread worldwide in a very short time. Although the countries took numerous precautions, the spread of the virus could not be controlled. Furthermore, due to the inability to maintain physical distance and the excess of shared surfaces, public transport services also increase the risk of spreading. This study analyzes the changes in perceptions and behavior of passengers who use public transportation via a survey. The survey is developed to assess the behavioral change of passengers pre and post-pandemic of COVID-19. Outcomes showed a notable shift among transportation modes due to closure of venues, utilization of distance education, partial curfews in Istanbul. A further focal point of the study is the passengers’ attitudes towards preventive measures and their perceptions on how well responsible bodies have implemented the measures. Thus, it provides valuable insights into the changes in the traveling habits of city residents, which help the policymakers of public transportation.
Transportation Research Record: Journal of the Transportation Research Board
Health care systems throughout the world are under pressure as a result of COVID-19. It is over t... more Health care systems throughout the world are under pressure as a result of COVID-19. It is over two years since the first case was announced in China and health care providers are continuing to struggle with this fatal infectious disease in intensive care units and inpatient wards. Meanwhile, the burden of postponed routine medical procedures has become greater as the pandemic has progressed. We believe that establishing separate health care institutions for infected and non-infected patients would provide safer and better quality health care services. The aim of this study is to find the appropriate number and location of dedicated health care institutions which would only treat individuals infected by a pandemic during an outbreak. For this purpose, a decision-making framework including two multi-objective mixed-integer programming models is developed. At the strategic level, the locations of designated pandemic hospitals are optimized. At the tactical level, we determine the loca...
Environmental guidelines in the automotive industry greatly emphasize the recycling, remanufactur... more Environmental guidelines in the automotive industry greatly emphasize the recycling, remanufacturing, and recovering of end-of-life vehicles (ELVs). Given the principle of extended producer responsibility, developing an effective reverse logistics network is the most significant digit ahead of the industry. However, initial attempts addressing the reverse logistics network design (RLND) problem were short-sighted, focusing on cost minimization. Undoubtedly, the whole concept of recycling was founded on the pillars of sustainability. Accordingly, reverse logistics network design must be motivated by long-term environmental and societal benefits. This fact has become even more prominent in the current pandemic environment as COVID-19 has added serious uncertainties and risks to the supply chain processes. This paper reiterates the essence of sustainability goals and proposes a multi-objective fuzzy mathematical model to RLND problem for ELVs under such a fragile and fuzzy environment....
Abstract Energy has a crucial role for the existence and social well-being of human. Among variou... more Abstract Energy has a crucial role for the existence and social well-being of human. Among various options, hydrogen is the promising energy carrier for sustainable energy systems. As an important source of hydrogen, Hydrogen Sulphide (H2S) is abundantly found in Black Sea waters and known as an environmental pollutant. The main aim of this study is to evaluate Thermochemical, Electrochemical, Thermal, Photochemical, Plasma, and Thermal methods as decomposition methods, which meet sustainability aspects better than other technologies, based on expert opinions. As sustainable criteria, economically feasibility, ecologically feasibility, efficiency, process simplicity, energy requirement, safety and reliability, applicability and operational suitability and technical maturity are considered to determine the most appropriate hydrogen production method. In this sense, we have suggested a new integrated Multi-Criteria-Decision-Making (MCDM) methodology consisting of stepwise weight assessment ratio analysis (SWARA) with fuzzy set theory (FST) and Weighted Aggregated Sum Product Assessment (WASPAS) by employing interval valued intuitionistic fuzzy sets (IVIFS) in the selection process. The contribution of the study is not only proposing a new method which hybridizes the SWARA and WASPAS under uncertainty but also selecting the most sustainable Hydrogen production method utilizing from H2S in the Black Sea in Turkey, considering sustainable criteria which are unavoidable in energy management problems. At the end, the results are discussed, and sensitivity and comparative analyses are utilized to check the robustness and feasibility of solutions. Consequently, electrochemical is selected as the best and most appropriate hydrogen production method in terms of providing high efficiency in conversion and sustainable processes, i.e handling, transporting and storing harmful chemicals.
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Papers by Nezir Aydin