Browsing by Author "Can, Gulin Feryal"

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A Pilot Study on Comparison of Teaching Workloads of Academicians Based on Working Periods During and Before the COVID-19 Pandemic
(Başkent Üniversitesi Mühendislik Fakültesi, 2025-01-25) Yorulmaz, Muhammed; Can, Gulin Feryal; Toktas, Pelin
The COVID-19 pandemic has had a profound impact on society, greatly changing the structure of social and working lives. Educational institutions, especially in higher education, were forced to suspend face-to-face education and switch to distance education. This change inevitably affected the working styles and workloads of academics. This study aims to explore the effects of the COVID-19 pandemic on academic teaching workloads by examining transaction data for a one-year period before and during the pandemic. The data were obtained from the system logs of a learning management system platform, which was used extensively during the pre-pandemic and pandemic periods, and were analyzed in terms of transaction density, day, and time of transactions. The findings from the pre-pandemic period showed that the academic workload was higher on weekdays than on weekends. However, with the transition to distance education during the pandemic, the difference between weekday and weekend workloads diminished significantly. Additionally, the working hours shifted during the pandemic by approximately one hour to later hours in the day.
An Advanced Stochastic Risk Assessment Approach Proposal Based on KEMIRA-M, QFD and Fine-Kinney Hybridization
(2021) Can, Gulin Feryal; Toktas, Pelin
In this study, an advanced stochastic risk assessment approach based on integration of advanced version of quality function deployment (AV-QFD) and Modified Kemeny Median Indicator Rank Accordance (KEMIRA-M) is proposed. It is aimed to perform a new criterion weighting procedure based on four different distributions as uniform, symmetric triangular, left asymmetric triangular, right asymmetric triangular distributions. The AV-QFD includes correlations between criteria (top roof of QFD), risk degrees (RDs) of risk types (RTs) (customer needs part of QFD), correlations between RTs and criteria sets (CSs) (in the middle of QFD) to obtain the criteria priorities. Correlations on the top roof of QFD comprises three types: correlations between criteria in the first CS, correlations between criteria in the second CS and correlations between criteria in both CSs. Additionally, Fine-Kinney method is performed in AV-QFD to compute RDs of RTs in the customer needs part. Then for each expert, the correlation-based importance degree (CBID) of each criterion is obtained to rank criteria for each CS. MATLAB code was performed to see the effect of different trial numbers and replications on risk assessment. It was observed that although uniform distribution provides the best value, the same alternative ranking was obtained for all distributions. In addition, right asymmetric triangular distribution converged to the best value rapidly in practice made in this study.
Assessment of Mental Workload and Academic Motivation in Medical Students
(2016) Atalay, Kumru Didem; Can, Gulin Feryal; Erdem, Saban Remzi; Muderrisoglu, Ibrahim Haldun; https://orcid.org/0000-0002-7537-2170; 27183939; AAJ-2370-2021
Objectives: To investigate the level of correlation and direction of linearity between academic motivation and subjective workload. Method: The study was conducted at Baskent University School of Medicine, Ankara, Turkey, from December 2013 to February 2014, and comprised Phase 5 Phase 6 medical students. Subjective workload level was determined by using National Aeronautics and Space Administration Task Load Index scale that was adapted to Turkish. Academic motivation values were obtained with the help of Academic Motivation Scale university form. SPSS 17 was used for statistical analysis. Results: Of the total 105 subjects, 65(62%) students were in Phase 5 and 40(38%) were in Phase 6. Of the Phase 5 students, 18(27.7%) were boys and 47(72.3%) were girls, while of the Phase 6 students, 16(40%) were boys and 24(60%) were girls. There were significant differences in Phase 5 and Phase 6 students for mental effort (p= 0.00) and physical effort (p= 0.00). The highest correlation in Phase 5 was between mental effort and intrinsic motivation (r= 0.343). For Phase 6, highest correlation was between effort and amotivation (r= -0.375). Conclusion: Subjective workload affected academic motivation in medical students.
A Case Study on Shopping Malls Attributes for Young Consumers
(2016) Can, Gulin Feryal; Kurtulmusoglu, Feride Bahar; Atalay, Kumru Didem
Purpose - This study aims to determine the mall criteria that are the most crucial for the youth market by determining the winning brand in comparison to other offerings to understand what is required to gain a competitive advantage and to differentiate a mall from its rivals. Design/methodology/approach - This study chose the Stochastic Multicriteria Acceptability Analysis-2 method to evaluate the mall preferences of young people. By using this method, the various criteria were evaluated for more than one alternative to find the best solution. JSMA program was used to analyze the data. The survey was administered using the mall intercept method to reduce sample bias. Findings - The study identifies that the criteria that have the highest impact on the mall preferences of young people are the mall campaigns for loyal customers; the traffic in the mall locality and the mall's parking facilities; the mall's facilities for disabled people; the quality of the mall locality; and the quality of the people visiting the mall. The study reveals that a mall's physical features, its facilities and the criteria related to employees have a very low impact on the mall choices of young people. The study further finds that the youth market has very low satisfaction levels for all of the identified criteria. This study reveals that this macro accessibility criterion is less relevant for the youth market than for the general population. Originality/value - Despite the importance of this market, there is insufficient research on the shopping behavior of young people. They have a considerable impact on the purchasing decisions of their families, significant disposable income and constitute the future market for the sector. This study uniquely enables the sequential ordering of customers' decision-making criteria and determines the effectiveness or impact of these criteria in the mall sector.
Does Gender Matter? Considering Gender of Service in the Airline Industry
(2018) Kurtulmusoglu, Feride Bahar; Can, Gulin Feryal; Pakdil, Fatma; Tolon, Metehan
Airline firms prioritize service features on the basis of customers' demand. While prioritizing these service features, successful positioning strategies are expected to focus on gender specific concerns. Given the fact that previous literature relies heavily on gender neutral strategies in airline industry, this study particularly addresses critical service features prioritized by female and male passengers by ranking airlines based on a multi-criteria decision-making method. Comfortable chair, seat space and leg room, and flexibility in reservation change were discovered as the three most impactful service features for female passengers. Availability of non-stop flight, frequency of flights, and airfare appeared as the other three most impactful service features among male passengers.
Evaluation of performance levels of students for moodle learning management system in terms of usability Criteria with PSI-Entropy-Marcos integration
(2022) Yorulmaz, Muhammet; Can, Gulin Feryal
The study, it is aimed to determine and compare the end-user performances within the scope of achieving the determined objectives while using the Moodle Learning Management System (LMS). Accordingly, considering multiple usability criteria, 18 users were prioritized in terms of their performances in using Moodie LMS. In this direction, Preference Selection Index (PSI) and Entropy integration was used to determine the importance weights of usability criteria, and the Measurement of Alternatives and Ranking according to Compromise Solution (MARCOS) method was used to prioritize the end-users. A new hybrid weighting method has been proposed by integrating the PSI method with the Entropy method, taking into account both the uncertainty in the performance values of the end-users according to the criteria and the preference change values of the criteria. This proposed method is applied for a three-dimensional initial decision matrix Thus, the traditional two-dimensional initial decision matrix which consists of the alternatives and the values that the alternatives take according to the criteria, has been developed and made more flexible. The objective criteria taken into account in the analysis were measured by the Morae V3 program, with the tasks defined as predetermined goals being performed by the users on the Moodie LMS. In addition, the criteria weights obtained from the proposed PSI-Entropy integration were used in the MARCOS method to rank the end-users according to their performance levels.
A FMEA based novel intuitionistic fuzzy approach proposal: Intuitionistic fuzzy advance MCDM and mathematical modeling integration
(2021) Yener, Yelda; Can, Gulin Feryal
This study proposes a novel three-stage intuitionistic fuzzy risk assessment (RA) approach based on Failure Modes and Effects Analysis (FMEA). In this study, it was paid attention for considering real constraints of firms such as capital, time etc. to prevent nan-fatal failure modes (FMs), interactions between FMs and risk level similarities created by risk factors (RFs). At the first stage of the proposed approach, RFs' weights are computed by a new intuitionistic fuzzy weighting method considering similarities between RFs for risk levels that they can create. At the second stage, Modified Intuitionistic Fuzzy Multi Attribute Border Approximation Area (MIF-MABAC) including interactions between FMs is used to determine the rankings of FMs by using Extended Haussdorff distance function. At the third stage, two intuitionistic fuzzy mathematical models are established to show the effect of the real constraints of the firm to identify the risk types (RTs) that must be avoided primarily. It was seen that the first model gives the same ranking results with the MIF-MABAC. Additionally, when including the real constraints, the first model can give the more suitable results than the second model. The results obtained from the first model show that experts' assessments and mathematical modeling identify the same FMs for preventing primarily. This study is the first one to suggest a new RA approach that reflects the real constraints of the firms to RA. Additionally, this is the first study that models' interactions between FMs and risk level similarities created by RFs.
Image processing based rapid upper limb assessment method
(2017) Can, Gulin Feryal; Figlali, Nilgun
Occupational Musculoskeletal System Disorders (OMSDs) are disorders that inflict a great deal of economical burden on enterprises and nations, decrease quality, productivity and cause inability to sustain livings of employees. One of the most important factor that cause OMSDs is working posture. In literature, there are various methods for determining risk levels of working postures. In this study because of its common usage, Rapid Upper Limb Assessment Method (RULA) that identfies hazard level created by working postures on employees' upper limb musculoskeletal health is selected for improving with image processing systems. It is necassary to improve RULA's performance due to complications stemming from its implementation method based on observation, lack of information on the best duration of observation, subjectivity on results and extensive analysis time etc. For compansate these requirements a modified method is proposed in this study named as Advanced RULA (ARULA). Reliability and validity analysis are implemented statistically for ARULA. As a result, ARULA is recommended as a practical tool for analyzing risk levels of working postures for tasks that contain intensive usage of upper extremity.
Improving the rapid office strain assessment method with an integrated multi-criteria decision making approach
(2020) Delice, Elif Kilic; Can, Gulin Feryal; Kahya, Emin
Nowadays, work-related musculoskeletal disorders (WMDs) are gradually increasing. This not only reduces work efficiency but also negatively affects workers' health. For this reason, it is important to design the working environment based on ergonomic principles in order to prevent WMDs before they occur. In addition, before starting ergonomic design improvement activities in the enterprises, it is necessary to identify the departments with high strain levels and evaluate the design of the office components in these departments. In this study, an integrated multi-criteria decision making (MCDM) approach was proposed based on the Rapid Office Strain Assessment (ROSA) method to determine the strain level caused by office components and to identify the departments to be ergonomically improved according to these levels. In the proposed approach, the strain level related to office components was evaluated by ROSA method. To determine the importance weights of office components on strain levels, Step-by-Step Weight Assessment Ratio Analysis (SWARA) was used. Weighted Aggregated Sum Product Assessment (WASPAS) method was applied to order the departments according to the strain levels. The proposed approach was implemented in a company operating in the aviation industry. As a result, the most important office component that increases the strain level was determined as the chair, while the Manufacturing Engineering and R & D departments were determined as the units with the highest strain levels. Additionally, by performing sensitivity and comparative analysis, changes in the departments' rankings were evaluated.
An Intutionistic Approach Based On Failure Mode and Effect Analysis for Prioritizing Corrective and Preventive Strategies
(2018) Can, Gulin Feryal
Although Failure Mode and Effect Analysis (FMEA) is a prominent approach that has been used with convenience as the most popular risk definition and evaluation tool related to a system, a product, or a service, it has several deficiencies. This study addresses these deficiencies and proposes a new intuitionistic approach, which combines FMEA and Weighted Aggregated Sum Product Assessment (WASPAS) by implementing a new intuitionistic scale. Intuitionistic FMEA-WASPAS can handle uncertainty, vagueness, and hesitancy of the risk evaluation process and provides flexibility for risk assessment. In this study, rankings of corrective-preventive strategies for failure modes (FMs) are obtained by the proposed approach. To compute Intuitionistic Fuzzy Risk Priority Numbers, occurrence, severity, detection, cost, duration of exposure, and system safety factors are used. A numerical example is also illustrated to present the practicality and effectiveness of the Intuitionistic FMEA-WASPAS approach.
A new approach for ergonomic risk assessment integrating KEMIRA, best-worst and MCDM methods
(2020) Delice, Elif Kilic; Can, Gulin Feryal
In this study, a new three-phase ergonomic risk assessment approach was proposed for manual lifting tasks to determine which worker has the highest ergonomic risk level considering two criteria sets as lifting-related criteria and human-related criteria. In the first phase, Modified Kemeny Median Indicator Ranks Accordance (KEMIRA-M) and a novel two-dimensional best-worst method (BWM) integration were proposed for weighting ergonomic risk criteria in two sets. In this way, weighting procedure of KEMIRA-M was advanced by the proposed two-dimensional BWM in a consistent manner and subjectivity in determining the best and the worst criteria in traditional BMW was prevented by using KEMIRA-M. Thus, the weaknesses of both methods have been developed. In the second phase, the rankings of workers were determined via utilizing multi-objective optimization on the basis of simple ratio analysis, multi-objective optimization by ratio analysis (MOORA) ratio, MOORA reference point and complex proportional assessment to see how worker rankings differ despite using the same advanced weighting approach based on KEMIRA-M and two-dimensional BWM integration. Finally, to aggregate these different ranking results, technique of precise order preference was applied. In this way, different viewpoints of each ranking approach can be reflected on a single worker's priority. The applicability of the proposed ergonomic risk assessment approach was demonstrated with a real application in tube manufacturing.
A new approach for ergonomic risk assessment integrating KEMIRA, best-worst and MCDM methods (vol 14, pg 313, 2020)
(2020) Delice, Elif Kilic; Can, Gulin Feryal
A New Hybrid Intuitionistic Approach for New Product Selection
(2018) Atalay, Kumru Didem; Can, Gulin Feryal
This paper proposes a new hybrid approach for multi-criteria decision-making problems combining intuitionistic fuzzy analytic hierarchy process and intuitionistic fuzzy multi-objective optimization by ratio analysis. Analytic hierarchy process has an inherent ability for handling intangible problems and implements a simple scale to represent evaluations in the structure of pairwise comparisons. Multi-objective optimization by ratio analysis optimizes the solution of a problem having two or more conflicting objectives, taking into account certain constraints. In real-life decision problems, evaluations of decision makers related to performance of alternatives and criteria weights can be expressed by linguistic terms comprising vagueness and uncertainty. These uncertain, vague and hesitant judgments of decision makers can be described more comprehensively by using intuitionistic fuzzy set theory. The proposed approach is a powerful tool for dealing with information which consists of hesitancy and vagueness. An illustrative example related to new product selection for a company is also presented to demonstrate the implementation of the approach.
A new multidimensional process type FMEA approach: Defense and aerospace industry application
(2022) Uslu, Tugce; Can, Gulin Feryal; Delice, Elif Kilic
Purpose: Failure Modes and Effects Analysis (FMEA), one of the most used methods in the literature, is a powerful risk assessment tool. However, it has many weaknesses that need to be improved. In this study, in order to increase the efficiency of using FMEA; a new multidimensional process type FMEA (MDPT-FMEA) approach is proposed. Theory and Methods: The MDPT-FMEA approach consists of three stages. At the first stage, Entropy, Preference Selection Index (PSI) and Criteria Importance through Inter-criteria Correlation (CRITIC) methods were used in the weighting of the risk criteria (RC). The different criteria weights obtained from these three different weighting methods were combined using the geometric mean operator and the integrated (final) weights were calculated. In the second stage, Evaluation based on Distance from Average Solution (EDAS), Combinative Distance-based Assessment (CODAS), Complex Proportional Assessment (COPRAS) to prioritize failure modes (FMs) were used. In the third stage, different FM priorities obtained from these three different ranking methods were combined using the Technique of Precise Order (TPOP) method. Results: The proposed MDPT-FMEA approach has been applied in a company operating in the defense and aerospace industry to evaluate the process-based FMs that may arise. In this study, different perspectives of different weighting and ranking methods are reflected in final criteria weights and final FM rankings. Conclusion: For the first time, different weighting and different ranking methods are combined in FMEA. As a result of the Spearman Correlation Coefficient calculation, the validity of both of the final criteria weights obtained and the final FM rankings were discussed.
A New Stochastic MCDM Approach Based on COPRAS
(2018) Ayrim, Yelda; Atalay, Kumru Didem; Can, Gulin Feryal
This study proposes a novel integrated Complex Proportional Assessment (COPRAS) approach by using stochastic decision process named as Stochastic COPRAS (COPRAS-S) to increase the evaluation performance of COPRAS. In COPRAS-S, criteria importance weights and the performance values of alternatives are determined by generating random numbers from uniform distribution in a range of minimum and maximum values of a limited number of decision-maker evaluations. Thus, the numbers of experts are increased and decision-making process is performed in an effective way because different opinions are incorporated. In addition, randomness feature brought with vagueness in decision is modeled in this process. A special normalization approach based on standard deviation is also implemented in COPRAS-S. In this way, cost and benefit type criteria are evaluated in a different way. This proposed stochastic structure for COPRAS is a practical and powerful tool that strengthens the decision.
A novel aggregated multiple criteria decision-making approach to evaluate the physical workload of workers
(2021) Ekinci, Elmas Burcu Mamak; Can, Gulin Feryal; AAE-4242-2020
Physical workload (PWL) is a measure of the physical resources consumed by a worker while performing a task. Analyzing the PWL of workers can aid experts in identifying workers whose working conditions should be improved. Identifying workers who are exposed to the highest PWL is essential for task continuity and occupational health. In this study, a new approach is proposed to prioritize workers according to their PWL levels. In the proposed approach, multiple criteria decision-making techniques are used because different factors can affect PWL levels. Eight criteria, that is, standard time, frequency of working posture, heart rate, the risk level of posture, noise level, lighting intensity, rest period, and perceived workload level are considered. In the evaluation process, criteria weights are computed using entropy considering measurements of the eight criteria for each worker. Using these weights in multiobjective optimization by simple ratio analysis, multiobjective optimization by ratio analysis, and multiattributive ideal-real comparative analysis methods, workers are ranked according to their PWL levels. The final order of workers is determined by aggregating different rankings obtained from these three methods, using the technique of precise order preference method. This study presents original research that can potentially contribute to the literature by considering different perspectives offered by various methods for PWL evaluation. It focuses on several different criteria by performing real measurements and subsequently ranking workers based on the aggregation of these measurements.
A Novel Multi-Criteria Decision-Making Approach Proposal Based on Kemira-M with Four Criteria Groups
(2022) Ay, Sefacan; Can, Gulin Feryal; Toktas, Pelin
This study aims to eliminate the subjectivity in the weight assignment process of Modified Kemeny Median Indicator Ranks Accordance (KEMIRA-M) and to remove the need for experts to reach a consensus on determining the criteria weights. Additionally, this study aims to apply KEMIRA-M for four different criteria groups and to prevent some criteria from taking a weight value of "0", as in other studies using KEMIRA-M. In this context, the weighting procedure of KEMIRA-M is advanced using three different ranking-based weighting methods such as Rank Sum (RS), Rank Exponent (RE) and Rank Reciprocal (RR) to operate Median Priority Components (MPCs) more effectively. Accordingly, to determine which weighting method for which criterion group is more suitable, the selection procedure of KEMIRA-M was applied and alternative rankings were obtained for 81 different weight set combinations. Additionally, MATLAB codes have been used to provide flexibility for the application of the proposed approach in a supplier selection problem selected for a case study.
Occupational health and safety performance evaluation of countries based on MAIRCA
(2020) Can, Gulin Feryal; Kiran, Muzaffer Bertan
Purpose The purpose of this paper is to develop an approach to compare occupational health and safety (OHS) performances of countries. Additionally, another aim is to debate the impacts of using recorded data and ratios for OHS performance evaluations. Design/methodology/approach The number of fatal accidents (NFAs), fatal accident rates (FARs), numbers of lost days (NLDs) and accident severity rates (ASRs) are determined as main criteria and six economic activity areas (EAAs) are considered as sub-criteria. Two different initial decision matrices are used as the initial decision matrix, the first of which consists of recorded data of countries related to NFAs and NLDs, and the second consists of FAR and ASR values as ratios. Importance weights of main and sub-criteria regarding the recorded data and ratios are determined using four different weighting ways. Countries are ranked via utilizing Multi-Attributive Ideal-Real Comparative Analysis considering two different initial decision matrices. Findings It can be stated that an evaluation based on ratios for comparison of OHS performance provides more realistic results. Additionally, increasing the effect of the FAR values using the 6,000 equivalent lost days factor is also important in terms of differentiating the data of the countries in question. Originality/value To the best of the authors' knowledge, there is no study in literature that discusses the ranking of countries by means of recorded data and ratios considering different criteria. Additionally, this study is a first in terms of the number of countries evaluated and the comparison of these countries according to their respective EAAs.
Six Sigma Project Prioritization and Selection Using AHP-CODAS Integration: A Case Study in Healthcare Industry
(2023) Can, Gulin Feryal; Toktas, Pelin; Pakdil, Fatma; https://orcid.org/0000-0001-6622-4646; D-7271-2018
Given the complex nature of Six Sigma project (SSP) prioritization and selection processes, multicriteria decision-making (MCDM) methods may help organizations identify the most effective projects. Considering potential limitations of subjective methods and advantages of MCDM methods, this article proposes a model that integrates analytical hierarchy process (AHP) and combinative distance-based assessment (CODAS) in SSP prioritization and selection process. In the proposed approach, AHP is employed to assign criteria weights, and CODAS is performed to determine priorities of SSPs. CODAS was advanced in term of its threshold function. Differences between Euclidean distances of two alternatives were compared, based on the standard deviation of Euclidean distances of all alternatives to overcome the subjectivity. This is the first study that combines AHP and CODAS methods for SSP selection, and CODAS is used with objective threshold value computation, and developed for the healthcare industry. In this article, ten SSPs were evaluated for four key criteria groups as financial, operational, patient centric, and organizational main criteria groups. In total, 18 subcriteria were considered under these four main criteria groups. This article provides a support for executives who make implementation plans for the potential SSPs.
Six Sigma Project Prioritization and Selection Using AHP-CODAS Integration: A Case Study in Healthcare Industry
(2021) Can, Gulin Feryal; Toktas, Pelin
Given the complex nature of Six Sigma project (SSP) prioritization and selection processes, multicriteria decision-making (MCDM) methods may help organizations identify the most effective projects. Considering potential limitations of subjective methods and advantages of MCDM methods, this article proposes a model that integrates analytical hierarchy process (AHP) and combinative distance-based assessment (CODAS) in SSP prioritization and selection process. In the proposed approach, AHP is employed to assign criteria weights, and CODAS is performed to determine priorities of SSPs. CODAS was advanced in term of its threshold function. Differences between Euclidean distances of two alternatives were compared, based on the standard deviation of Euclidean distances of all alternatives to overcome the subjectivity. This is the first study that combines AHP and CODAS methods for SSP selection, and CODAS is used with objective threshold value computation, and developed for the healthcare industry. In this article, ten SSPs were evaluated for four key criteria groups as financial, operational, patient centric, and organizational main criteria groups. In total, 18 subcriteria were considered under these four main criteria groups. This article provides a support for executives who make implementation plans for the potential SSPs.