Başar Öztayşi

Başar Öztayşi
Istanbul Technical University · Department of Industrial Engineering

PhD

About

234
Publications
60,509
Reads
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4,035
Citations
Citations since 2017
148 Research Items
3476 Citations
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20172018201920202021202220230200400600
20172018201920202021202220230200400600
20172018201920202021202220230200400600
Additional affiliations
October 2013 - October 2015
Istanbul Technical University
Position
  • Professor (Assistant)

Publications

Publications (234)
Chapter
Car rental is one of the most important industries worldwide in terms of tourism and professional travel. However, due to high initial costs and inadequate planning brings causes capacity problems which lead to potential revenue loss. Considering the high volatility in tourism and the high costs of facilitating a car rental location, forecast model...
Chapter
Digital transformation (DT) is the integration of digital technology by transforming all manual and semi-manual processes of business into full digital processes. In this chapter we review the DT status of the business sectors automotive, energy, smart manufacturing, white goods, health, banking, tourism, insurance, education, smart cities, and tra...
Article
When a decision maker is not sure in assigning a value for a pairwise comparison, he/she should assign a fuzzy value such as ‘between 3 and 4’ or ‘around 5’. These expressions can be represented by fuzzy numbers, which make the use of fuzzy AHP methods possible. Each new fuzzy set extension has caused new fuzzy AHP method to be developed by researc...
Article
Digital transformation necessitates fundamental changes in business processes, business models, and even cultures of the companies. DT projects provide a substantial value to the business competition and effect their market shares. In order to reach these results, digital transformation projects should be carefully analyzed and evaluated. In this p...
Article
Third party logistics (3PL) supplier selection problem is a multi-criteria selection problem that is frequently discussed in the literature. Medicine is a fundamental element for human health and drug transportation must be carried out on time and under conditions that will ensure that the drug does not lose its physical properties. Therefore, the...
Chapter
Modanisa is a global E-commerce company which provide modest fashion products. Since each country has different currency and different economic conditions, purchasing capacity of the residents change. As a result, the price that the market is willing to pay vary among the countries. Price sensitivity is the degree to which demand changes when the c...
Chapter
Cloud Service Provider selection is a multi-criteria decision making problem involving many criteria, which some of them may be conflicting. Alternatives under these criteria are generally assessed by using linguistic terms such as very high, excellent and absolutely low, which includes vagueness and impreciseness. In this paper, the uncertainties...
Chapter
Global warming is disturbing both the environment and quality of life. A cause of global warming is greenhouse gas (GHG) emissions which are caused by using fossil fuels for transportation and power generation. As a novel source of energy, the world is moving towards renewable and clean energy. In the transportation sector, usage of electric vehicl...
Chapter
The Internet of Things (IoT) platform selection is one of the important steps that leads to digital transformation. The companies should consider multiple factors such as return of investment, the flexibility to change the IoT platform, the future performance, sustainability of the platform, the maturity level of IoT platform, security of the IT pl...
Chapter
Association rule mining (ARM) refers to a procedure that focuses on finding frequent patterns in various data sources. The most commonly used area is the retail sales data and rules which show an association between sales of two products are investigated. To this end, sales data is preprocessed, and algorithms are used to find the association rules...
Chapter
The Internet of Things (IoT) platform selection is one of the important steps that leads to digital transformation. The companies should consider multiple factors such as return of investment, the flexibility to change the IoT platform, the future performance, sustainability of the platform, the maturity level of IoT platform, security of the IT pl...
Chapter
Business Analytics is one of the business management methods that deals with descriptive models which create meaningful insights to support and reinforce the business performance. It is one of the most widely used topics in business and Industry. The first state of each analytics is collecting valid data. Descriptive Analytics is the first stage of...
Chapter
Nowadays, unpaid invoices are major concerns in many industries or service companies that seriously affect firms’ cash flows, credit ratings, and firms’ image. To overcome the financial problems caused by unpaid debts, managing and controlling these debts is a vital task for companies’ financial survival. Unpaid receivables are collected by the com...
Poster
Full-text available
INFUS 2022 International Conference July 19-21, 2022 Izmir Turkey
Article
Full-text available
Online stores assist customers in buying the desired products online. Great competition in the e-commerce sector necessitates technology development. Many e-commerce systems not only present products but also offer similar products to increase online customer interest. Due to high product variety, analyzing products sold together similar to a recom...
Chapter
Customer segmentation is essential for marketing, communication, and even operations management activities. E-commerce provides the data required for novel perspectives to customer segmentation. In this study, we focus on customer segmentation based on purchase variety. To this end, first, the data is preprocessed, and the optimal customer number i...
Chapter
EXtension of the PROMethee (EXPROM) methods were first introduced in 1991. These methods try to find a solution for ranking the alternatives more accurately using the available information. EXPROM-I method performs a partial ranking of alternatives whereas EXPROM-II does a full ranking of the alternatives. Vague and imprecise data of multi-criteria...
Book
This book presents recent research in intelligent and fuzzy techniques. Emerging conditions such as pandemic, wars, natural disasters and various high technologies force people for significant changes in business and social life. The adoption of digital technologies to transform services or businesses, through replacing non-digital or manual proces...
Chapter
Customer relationship management (CRM) and marketing analytics is a combination of techniques, technologies, and strategies that serve to create and deliver value to profitable customers. It involves internal business processes and functions (such as marketing, sales) as well as external influences (such as competitors). CRM systems collect, analyz...
Article
The REGIME method is an easy to understand techniques which is based on pairwise comparisons and which can use qualitative data for decision making problems. The steps of the technique are simple and can be easily adopted to complex decision problems. Classical REGIME techniques use crisp numbers to evaluate qualitative evaluations. In this paper w...
Article
Full-text available
RFM (Recency, Frequency, Monetary) technique is a common and useful way for customer segmentation analysis, which is a must in sales, marketing and operation management. RFM mainly uses transaction data to investigate customers shopping behaviour. In this study, a fuzzy-based RFM method that uses renting data from a car rental company was applied....
Chapter
Full-text available
In this competitive world, companies need to manage their arrears of debtors to survive. Big companies monthly face thousands of debt cases from their customers and if these debtor customers do not pay their debts within the specified period, these cases will enter the legal stage as legal debt collection that is handled by experienced lawyers. At...
Poster
Full-text available
Intelligent and Fuzzy Systems: Emerging Conditions and Digital Transformation Emerging conditions such as pandemic, wars, natural disasters and various high technologies force us for significant changes in our business and social life. Pandemic caused all of us to live under quarantine for a certain period of time and serious restrictions in our bu...
Chapter
The REGIME method, initially introduced by Hinloopen et al. [1, 2] is based on paired comparison methods which are easy to understand and uses qualitative data only in a mathematically justifiable way. The computational steps of the method are simple and can be easily apply to various complex problems. Classical REGIME techniques uses crisp numbers...
Article
Autonomous vehicles are one of the emergent advances of the new technology era that has the prospective to redesign transportation structures. Understanding and measuring the limitations of adopting autonomous vehicles and selecting the best autonomous vehicle based on different aspects is crucial for enhancing the adoption process. Defining the cr...
Article
Linguistic terms are quite suitable to make evaluations in multiple criteria decision making problems since humans prefer them rather than sharp evaluations. When linguistic evaluations are used in the decision matrix instead of exact numerical values, fuzzy set theory can capture the vagueness in the linguistic evaluations. Ordinary fuzzy sets hav...
Article
Companies started to determine their strategies based on intelligent data analysis due to stagey enhance data production. Literature reviews show that the number of resources where demand estimation, location analysis, and decision-making technique applied together with the machine learning method is low in all sectors and almost none in the shoppi...
Chapter
Humanoid robots will be very usable in human society to improve the quality of human life in the future. They can be used for assisting the sick and elderly people, and dirty or dangerous jobs. Human behaviors are mostly emotional and based on the degrees of feelings such as being strongly sad or being slightly happy. Fuzzy sets theory can be very...
Chapter
Intuitionistic fuzzy sets (IFS) have been often used in modeling the problems under vagueness and impreciseness in order to better define the problems together with the hesitancy of decision makers. IFS have been often employed in modeling decision making problems in the literature. Human decision making process can be used in humanoid robots by im...
Chapter
In today’s economy, companies have to constantly develop new strategies and have to choose whether to expand into new markets, stabilize in or exit from the existing markets. The entry in to the new markets is a complex strategic decision; it does not only involve the entry mode decision but also in some occasions involve partner selection. When th...
Chapter
The fact that a film is a hedonic product makes it difficult to assess its quality before consumption, therefore consumers who want to reduce uncertainty need various quality signals in their decision-making processes. In recent years, adding to movie-related information, user reviews or ratings on online movie databases have become important quali...
Chapter
As mobile devices are, highly adopted, indoor location tracking systems started to emerge. Companies can use these indoor location-tracking systems to better understand their customers and get an insight into their intentions and needs. In this paper, different indoor location tracking systems are evaluated. Since there are various evaluation persp...
Chapter
RFM (recency, frequency, monetary) analysis is an essential tool for customer segmentation, which is very important for marketing, communication, and even operations management activities. RFM is a widely adopted segmentation tool since it can be accomplished by using purchase transactions. In this study, we use the purchase transactions of Modanis...
Chapter
Beacon technology enables applications that provide location-based services such as notifications, tracking, and navigation via smart mobile devices. One of the most commonly adopted business models based on beacon technology is location-based advertisements. In this model, target customers are defined, and the most appropriate advertisement is sen...
Chapter
Energy investments are highly risky due to the uncertainties of the energy market. Over the past two decades, the usage of wind energy has been increased dramatically. Appropriate wind energy investment valuations are vital for both the public and private sectors. The fluctuations in the energy prices, the uncertainties in the production levels and...
Chapter
Fuzzy sets extensions have been often used in the modeling of problems including vagueness and impreciseness in order to better define the membership functions together with the hesitancy of decision makers. More than 20 different extensions of ordinary fuzzy sets have appeared in the literature after the introductions of ordinary fuzzy sets by Zad...
Book
This book gathers the most recent developments in fuzzy & intelligence systems and real complex systems presented at INFUS 2020, held in Istanbul on July 21–23, 2020. The INFUS conferences are a well-established international research forum to advance the foundations and applications of intelligent and fuzzy systems, computational intelligence, and...
Article
In a general manner, customer relationship management engages in understanding customer needs and meet them. Most of the investments are either far from customer needs or based on a primitive data collection method. However, customers mainly do not behave with the same ideas to shop in the retail domain. Several studies aim to understand the visiti...
Article
The catastrophes due to widespread outbreaks create a long-standing distraction and have an accelerating transmission. The uncontrolled outbreaks cause not only health-related problems but also supply chain related problems. The outbreak caused by the coronavirus (COVID-19) shows how vulnerable the Healthcare systems and the supporting systems such...
Article
Location-Based Systems enable novel business models that can locate a person and send an action or message to him/her. One of the most commonly adopted location-based business models is location-based advertisements. Companies can send customized messages to target customers by using location-based ads. The model is promising since the conversion r...
Article
The motion picture industry is one of the largest industries worldwide and has significant importance in the global economy. Considering the high stakes and high risks in the industry, forecast models and decision support systems are gaining importance. Several attempts have been made to estimate the theatrical performance of a movie before or at t...
Article
Pythagorean fuzzy sets (PFS) are an extension of intuitionistic fuzzy sets introduced by Atanassov [1]. PFSs have the advantage of providing larger domains for assigning membership and non-membership degrees satisfying that their squared sum is at most equal to one. PFS have been often used in modeling the problems under vagueness and impreciseness...
Conference Paper
Intuitionistic fuzzy sets (IFS) have been very popular in the literature after they were introduced by Atanassov (1986). Several extensions of IFS have been proposed such as Pythagorean fuzzy sets (PFS), fermatean fuzzy sets (FFS), q-rung orthopair fuzzy sets, picture fuzzy sets (PiFS), and spherical fuzzy sets (SFS). The main difference among thes...
Conference Paper
Learning analytics is the measurement of student progress by the collecting, analysis and reporting data in the learning environment. Learning analytics methods try to find out the dependent pattern in dataset gathered. Learning Analytics improve student outcomes in several ways, first, using learning analytics leads to measure student success corr...
Conference Paper
Spherical fuzzy sets are the latest extension of the ordinary fuzzy sets, which are based on three independent parameters, namely membership degree, non-membership degree and hesitancy degree. The squared sum of these parameters must be equal or less than “1”. Several papers have been published on the arithmetic operations, aggregation operators, d...
Conference Paper
Intuitionistic fuzzy sets are the main source of several recent extensions of the ordinary fuzzy sets such as Pythagorean fuzzy sets, picture fuzzy sets, neutrosophic sets and q-rung orthopair fuzzy sets. In addition to these, one of the latest extensions of these types of fuzzy sets is Spherical fuzzy sets, which have been often employed in many m...
Conference Paper
With the emerging technologies, collecting and processing data about the behaviors of customers or employees in a specific location has become possible. The purpose of this paper is to evaluate existing data collection technologies. Technology evaluation problem is handled as a multi-criteria decision-making (MCDM) problem. In this manner, a decisi...
Conference Paper
Solar energy is a reliable energy source that is important for the environmental sustainability. Solar energy investments become crucial for the countries like Turkey that does not have natural fossil based fuels but has a great potential of solar energy. In order to give better solar energy investment decisions, the uncertainties and ambiguities i...
Conference Paper
Industry 4.0, indicated as the "Fourth Industrial Revolution", also pointed out as "integrated industry", "smart manufacturing" and "industrial internet of things", has taken a great attention in terms of the potential to reflect entire industries' actions by transforming the production to a fully automated and self-coordinated digital system. This...
Article
Models of Fuzzy Multi-Criteria Decision Analysis (FMCDA) are based, as a rule, on different approaches to fuzzy extension of source MCDA methods. For this, simplified models are used to approximate the functions of fuzzy variables with propagation of parametric fuzzy numbers (FNs) through all calculations. In this paper, authors suggest a novel app...
Poster
Full-text available
Welcome to INFUS 2020, where you will find everything that you expect from a conference. INFUS is an acronym for Intelligent and Fuzzy Systems. It is a well-established international research forum to advance the foundations and applications of intelligent and fuzzy systems, computational intelligence, and soft computing for applied research in ge...
Conference Paper
Intuitionistic fuzzy sets (Atanassov, 1986) are the sets whose elements have degrees of membership and non-membership satisfying the condition that their sum is at most equal to one. Thus, an expert can express his/her hesitancy through IFS whereas it is not possible with ordinary fuzzy sets. This paper presents a literature review on intuitionisti...
Article
Purpose The companies are struggling to collect invoices due to the decrease in the economic growth. This global trend does not only affect undeveloped countries, but it also has a strong impact on the developed countries. Improving the debt collection process become a significant element to maintain financial stability. The institutions that are s...
Chapter
An automated storage and retrieval system (AS/RS) is a type of warehouse automation technology specifically designed to buffer, store, and retrieve product and inventory on demand. AS/RS technology varies substantially, and can consist of shuttles, cranes, carousels, vertical lift modules (VLMs), micro-loads, mini-loads, unit-loads, or other system...
Chapter
Debt collection is a problematic area of the lenders. When the lenders cannot collect their debts, they rent debt collection firms for their debts to be collected from borrowers. Selection among numerous collection firms is another challenging problem with several criteria under uncertainty. Based on the past performances of the collection firms, w...
Chapter
Education is important for the personal, social and economic development. In this study, we focus on an innovative feedback system design for an education organization, which operates all over Turkey. The content of the educations are on science and mathematics for kids, In the classical model, the education content is generated at the center and t...
Chapter
Full-text available
Motion picture industry is one of the largest industries worldwide and has a significant importance in the global economy. However, still each year, there is a considerable number of movies fail even to break even and lose a lot of money. Considering the high stakes and high risks in the industry forecast models and decision support systems are gai...
Chapter
Entrepreneurial activities are essential for increasing a nation’s wealth. Successful innovations initiated by the entrepreneurial ventures/startups may improve life quality, create new business areas and decrease the unemployment rate. Therefore, many countries provide various supports including financial support to entrepreneurial companies or st...
Chapter
The objective of this paper is to discover and prevent organized financial crimes among various entities such as applicants, guarantors, customers, staff, portfolio managers, beneficiaries, agencies, experts and services. A sophisticated visual analysis solution can help users to detect conspicuous links between different entities. Most of the inst...
Chapter
Customer segmentation is the process of dividing customers into groups having similar features. Deciding the type of segmentation is a multiattribute decision problem that should be considered under vague and imprecise environment. This paper compares the customer segmentation methods based on neutrosophic aggregation operators. Two different neutr...
Chapter
Indoor customers may have different purposes to visit a shopping mall. Understanding the visiting aims results in better customer relationship management. One of the ways to explain the customer purpose is to discover customer paths. Customers mainly visit stores related to their purposes. The main problem is to discover customer paths from paths....
Chapter
Performance measurement (PM) is defined as the process of collecting, analyzing and/or reporting information regarding the performance of individuals, teams or the whole organization. The first and one of the most important steps in performance measurement is determining the performance indicators and their weights. In this study, we focus on perfo...
Chapter
Location Segmentation has several strategic and tactical implications in marketing products and services. Despite hard clustering methods having several weaknesses, they remain widely applied in marketing studies. Alternative segmentation methods such as fuzzy methods are rarely adapted to understand consumer location visiting tendency. In this stu...
Chapter
Customer oriented systems provides advantages to companies in competitive environment. Understanding customers is a fundamental problem to present individualized offers. Gender information, which is one of the demographic information of customers, mainly cannot be obtained by data collection technologies. Therefore, various techniques are developed...
Chapter
The technological developments let people use mobile phones and benefit from mobile phones in many areas of their lives. People benefit from various services of the operator companies. Therefore, operator companies have an extensive customer base. Yet, collecting the fees of their services from customers can be hard. When the customers regret or de...
Article
Full-text available
TOPSIS is one of the most claimed methods within Multi-Criteria Decision Analysis (MCDA). In this paper, novel general approach to implementation of TOPSIS in the fuzzy environment is presented. Within the suggested approach to Fuzzy TOPSIS (FTOPSIS), fuzzy criterion values and fuzzy weight coefficients with the use of Fuzzy Numbers (FNs) of a gene...
Article
As a vital component of digitalization software development has become a very important issue for management. Software development is the process of, identifying, planning, coding, documenting, testing, and fixing operations accomplished for creating and maintaining different applications. Since the process is complex and various individuals work a...
Book
Proceedings of the INFUS 2019 Conference, Istanbul, Turkey, July 23–25, 2019
Chapter
Energy Demand Side Management (EDSM) is defined as the modification of consumer demand for energy. EDSM can be used for different purposes such as reducing peak demand, filling low demand time, strategic demand savings, strategic growth of demand, load-shifting, and flexible load shaping. EDSM can be managed by either Direct Load Control, in which...
Chapter
Energy Demand Side Management (EDSM) is defined as the modification of consumer demand for energy. EDSM can be used for different purposes such as reducing peak demand, filling low demand time, strategic demand savings, strategic growth of demand, load-shifting, and flexible load shaping. EDSM can be managed by either Direct Load Control, in which...
Article
Location selection decisions contain many factors that may be conflicting themselves. Today it is proven that location selection is a part of strategic management activity for armies. This research uses a location selection analysis approach for the maintenance facility for military armored vehicles using a multiexpert and multicriteria interval-va...
Article
Full-text available
The study presents some results of customer paths’ analysis in a shopping mall. Bluetooth-based technology is used to collect data. The event log containing spatiotemporal information is analyzed with process mining. Process mining is a technique that enables one to see the whole process contrary to data-centric methods. The use of process mining c...
Article
Full-text available
Nowadays, unpaid invoices and unpaid credits are becoming more and more common. Large amounts of data regarding these debts are collected and stored by debt collection agencies. Early debt collection processes aim at collecting payments from creditors or debtors before the legal procedure starts. In order to be successful and be able to collect max...
Article
Full-text available
Intuitionistic fuzzy sets (IFS) proposed by Atanassov (1983, 1986) are a generalization of ordinary fuzzy sets. They incorporate the degree of hesitation which is defined as 1 minus the sum of membership and non-membership degrees. Type-2 fuzzy sets were first introduced by Zadeh (1975) as an extension of the concept of an ordinary fuzzy set. Type-...