Papers by CEMALETTİN KUBAT

Expert Systems with Applications
Abstract Classification is one of the important tasks in data mining and machine learning. Classi... more Abstract Classification is one of the important tasks in data mining and machine learning. Classification performance depends on many factors as well as data characteristics. Some algorithms are known to work better with discrete data. In contrast, most real-world data contain continuous variables. For algorithms working with discrete data, these continuous variables must be converted to discrete ones. In this process called discretization, continuous variables are converted to their corresponding discrete variables. In this paper, four Chi-square based supervised discretization algorithms ChiMerge(ChiM), Chi2, Extended Chi2(ExtChi2) and Modified Chi2(ModChi2) were used. In the literature, the performance of these algorithms is often tested with decision trees and Naive Bayes classifiers. In this study, differently, four sets of data discretized by these algorithms were classified with ensemble methods. Classification accuracies for these data sets were obtained through using a stratified 10-fold cross-validation method. The classification performance of the original and discrete data sets of the methods is presented comparatively. According to the results, the performance of the discrete data is more successful than the original data.

International Journal of Intelligent Systems and Applications in Engineering, 2021
Missing data is a major problem in terms of both machine learning and data mining methods. Like m... more Missing data is a major problem in terms of both machine learning and data mining methods. Like most of these methods do not work with missing data, negative results may occur on the performance of the working ones, also. Imputation is a data preprocessing method used to replace missing data with appropriate values. This study aims at developing a hybrid modified imputation method based on deep learning approach. For this purpose, we use Random Forest and Datawig deep learning imputation (called RF-DLI) methods together. Datawig is a deep learning-based library that supports missing value imputation for all types of data. RF-DLI approach includes the following steps to impute missing data. First, the importance of each attribute of the data set is determined with Random Forest (RF). Second, the most important 50% of the attributes are selected. Finally, each missing value is imputed with datawig (DLI) using these most important attributes. The study uses six real-world data sets from different fields with 30% missing data. The imputation performance of RF-DLI is compared to K-Nearest Neighbors (KNN), Multiple Imputation by Chained Equations (MICE), MEAN imputation, and Principle Component Analysis (PCA) imputation approaches in terms of Mean Absolute Error (MAE), Root Mean Square Error (RMSE), and R-square (R 2 ) evaluation metrics. The results show that in most cases, the RF-DLI approach has better imputation performance than the other techniques mentioned.

GAZI UNIV, FAC ENGINEERING ARCHITECTURE, 2012
In the future, Virtual Laboratories will have a very important place for distant education which ... more In the future, Virtual Laboratories will have a very important place for distant education which has real applications of laboratory tests and experiment applications. It is fact that virtual laboratories necessity is inevitable because the requirements of materials, place, staff and above all, time and financial requirements for establishment of real laboratories. Virtual Laboratories, if its visuality qualifications are convenient, can easily provide like real laboratories which's users can observe the experiments with making changes on the parameters. In this study tensile test was examined for virtual laboratories and it is also aimed at designing the tensile test in virtual environments for different tensile speeds. An artificial neural network was generated from the values of a material which was stressed in different speeds and intermediate speed values were predicted by this artificial neural network

The aim of the study is to bring forth some historical facts, with supporting scientific evidence... more The aim of the study is to bring forth some historical facts, with supporting scientific evidence, regarding the first Quality System (Ahilik) which was developed and applied by the Ottoman Turks, hence contributing to the Total Quality Management (TQM) by setting a historical perspective. As was TQM, Ahi Order was adopted to create an organizational culture, to educate and train the employees via continuous training programs and to put in place a management system entirely focused on human relations. The quality was determined by the consumers and consumer rights were protected by the system. Ahi Organization, going beyond TQM system, had strict rules on professional ethics. Social behaviour was seen as an indivisible unit and consequently it was thought that any unethical behaviour in social life would reflect on the work place, thus ethics would control the social behaviour closely. Manufacturers and/or traders had to behave ethically in production, trade and even in their social...

International Symposium for Production Research, ISPR 2020 --24 September 2020 through 26 Septemb... more International Symposium for Production Research, ISPR 2020 --24 September 2020 through 26 September 2020 -- -- 2508692-s2.0-85096464270In today’s world, humanity was obliged to learn living with disasters. Although disasters are mostly accepted as events that occur outside the control of human beings, the natural disasters that have increased due to reasons such as the development of technology, the unconscious destruction the environment of human beings etc., have started to be a part of our daily life in today’s world. Disaster Management discipline has been formed due to the needs such as managing disasters, minimizing damages caused by disasters and even developing methods for disaster prevention. Disaster management is a dynamic process with a very high risk coefficient. It is critical to establish strategies and to take advantage of technology correctly and adequately for taking precautionary warnings prior to disasters, providing effective intervention at the time of disaster and ensuring normalization after disaster. Based on the current importance of the subject, in this study a general strategic model was presented about IoT application areas related to the three phases of disaster management (before disaster, during disaster and after disaster). © 2021, The Editor(s) (if applicable) and The Author(s), under exclusive license to Springer Nature Switzerland AG

Computers & Industrial Engineering, 2020
Due to the factors such as technological developments, industrialization, population growth, etc.... more Due to the factors such as technological developments, industrialization, population growth, etc. the energy need in the world is constantly increasing and the available resources are insufficient to meet this need. Therefore, the search for alternative energy sources has accelerated recently and this situation has directed the countries to renewable energy. Although the use of renewable energy had gone until before of the first industrial revolution, it has become a very popular area today due to significantly eliminating the increasing concerns related to the security of energy supply, being environmentally friendly, and has positive economic effects. For this reason, nowadays countries form their strategies, policies, and goals related to the energy sector with a focus on renewable energy and make serious investments in this field. Owing to the current importance of the issue, in this study it is aimed to determine how the optimum investment decisions could be taken at the renewable energy sector in Turkey. Five renewable energy alternatives which are hydropower, solar energy, wind energy, geothermal energy and biomass energy, were taken into consideration. First of all, using the Fuzzy Analytical Hierarchy Process and the Evaluation Based on Distance from Average Solution methods, the importance weights of renewable energy alternatives were found and they were prioritized. Afterwards, the risks of renewable energy alternatives were found with the Fuzzy Failure Mode and Effect Analysis. Finally, the best alternatives were determined by comparing the evaluation results. When the results of study were analyzed it was clearly seen Turkey should focus on hydropower and wind energy in renewable energy investments. ☆ This paper is an extension of work originally presented in 10th International Symposium on Intelligent Manufacturing and Service Systems (IMSS'19) (Karatop,

International Journal of Scientific and Technological Research, 2019
Detailed analysis of the products that are accepted as status indicators in the society must be d... more Detailed analysis of the products that are accepted as status indicators in the society must be done before the presentation to the market. Cars are also considered as status indicators in society. Performing perception analysis before the presentation to the market will provide many benefits. For products that have not been produced, perception analysis also reveals the expectation of the customer. It can be said that the individual perceives the risk about the product if perception of potential customers is creating a negative impact on the buying trends. Customer's perception of risk affects the purchasing decision of the individual in terms of financial, psychological, physical, functional, social and time criteria. Risk perception encountered in real life in all areas is a multi-criteria concept with uncertainty. In the study, fuzzy logic method which gives successful results in uncertainties was used together with AHP method which is commonly used in multi-criteria decision making (MCDM) problems. The article used the risk perception in Turkish Brand Patented Automobile (TBPA) production with fuzzy analytic hierarchical process (FAHP) method. The potential customer's risk perception and wishes and expectations are presented.

Akademik İncelemeler Dergisi, 2018
Armand Vallin Feigenbaum’un 1957’de yayınladığı makalesinde Toplam Kalite Yönetimi (TKY) dünyada ... more Armand Vallin Feigenbaum’un 1957’de yayınladığı makalesinde Toplam Kalite Yönetimi (TKY) dünyada ilk kez duyulmakla birlikte, 1300’lü yıllarda Anadolu’da Türkler tarafından kalite yönetiminin bugün kazandığı anlamdan daha kapsamlı bir şekilde kullanıldığı bilinmektedir. Bu sistemin adı; Ahiliktir. 13-20. yüzyıl arasında Anadolu Türklerine özgü üretim ve ticarette kullanılan, sosyal hayatı düzenleyen sistem olan Ahilik, TKY’nin bir adım ötesine geçerek, meslek etiği konusunda kesin kurallar koymuş; aynı zamanda toplumun huzurunu sağlama konusunda tedbirler almış, toplumu etik davranışa yönlendirmiştir. TKY Ishikawa tarafından “yönetimde bir düşünce devrimi” olarak nitelendirilmekle beraber bu devrimin ilk önce 13. yüzyılda Anadolu’da gerçekleştirildiğini söyleyebiliriz. Hatta TKY de konu edilmeyen, ancak Ahilik Sisteminde kullanılan birçok ilke bulunmaktadır. Bu çalışmanın amacı; kalite yönetimi sisteminin dünyada ilk kez Anadolu’da Türkler tarafından kullanıldığını, geliştirildiğini...

Sakarya University Journal of Science, 2018
In order to outmaneuver increasing competition, organizations must plan their strategies for mana... more In order to outmaneuver increasing competition, organizations must plan their strategies for managing the future. Yet, planning is not solely adequate. It is important to ensure the sustainability of feasible plans which are supported by performance evaluations, and to focus on strategies that which pay attention to demands and expectations of stakeholders. The most prominent features of the real-life problems are multiple criteria, complexity and uncertainty. Benefiting from expert and stakeholder views help to reach optimal solutions of those problems. Taking advantage of artificial intelligence techniques would also contribute to the achievement of optimal results. Strategy Focused Model (SFM) aims to provide the most optimal possible solutions to real-life problems that require multi-criteria decision making. In SFM, the views of stakeholders and strategists are input into the decision making process. The main criteria of a problem establish the mainframe of the model, and th...

Computers & Industrial Engineering, 2016
Special issue on ''Contributions to society of information, manufacturing and service systems dev... more Special issue on ''Contributions to society of information, manufacturing and service systems developments" The Joint International Symposium combining The 44th International Conference on Computers & Industrial Engineering (CIE44) and Intelligent Manufacturing and Service Systems 2014 (IMS14) was organized to disseminate recent developments, significant technical applications, case studies and survey results in the areas of Information, Manufacturing and Service Systems and related areas. The Symposium was organized by the Department of Industrial Engineering, Sakarya University (Turkey) in Adile Sultan Palace, Istanbul, Turkey during October 14th to 16th, 2014. This special issue contains enhanced versions of selected papers from this conference, as well as others submitted by authors of papers falling within the same scope. All papers went through the double-blind review process followed by the journal. The field of industrial engineering has been undergoing a great deal of transformation in its attempt to address real manufacturing, service, and societal issues. In so doing it has drawn upon new advances in technology and methodology, and has contributed to their development. Examples of new approaches included Industry 4.0, the Internet of Things, big data, and cloud computing. One important direction in industrial engineering research is the attempt to integrate the separate manufacturing, transportation and distribution components of real life systems,

Computers & Industrial Engineering, 2016
A conceptual model is designed for gathering all Virtual Labs in a common base.Multi-agent based ... more A conceptual model is designed for gathering all Virtual Labs in a common base.Multi-agent based integrated Virtual Labs management system is proposed.Possible interactions between Virtual Labs are introduced.This model will help to relax Virtual Labs' boundary problems.This study can give useful insights to the Virtual Lab researchers. With the rapid development in information technologies, numerous Virtual laboratory (VL) studies are being conducted in various fields such as material science, computer science, chemistry and education. While the number of VL studies are rising, possible interactions between these VLs have not been studied yet. The aim of this study is to create a framework in order to gather all VLs in a common base by building interactions between VLs via a multi-agent system (MAS) approach. Cloud-Based Integrated Virtual Laboratories (CIVIL) model has been proposed as a conceptual framework of collaborative networks of a cloud system with the help of MAS. The boundaries of the integrated problem are determined and schematized within the scope of conceptual modeling. Thereafter probable entities that may interact in the framework are included in the MAS model. Communications and interactions between these entities, aims and performance indicators of defined agents are also listed.
Journal of Intelligent Manufacturing, 2015
Computers & Industrial Engineering, 2015

Computers & Industrial Engineering, 2015
Nowadays, manufacturing companies have been working based on people-oriented approach. Customer s... more Nowadays, manufacturing companies have been working based on people-oriented approach. Customer satisfaction is currently not only for external customers but also required for internal customers. In this context, human resource is one of the most important resources to manage and vital for manufacturing companies in terms of customers, employees and managers. With this perception, The Human Resource Management (HRM) issue is emerged. HRM enables effective and efficient management of human resources. Manufacturing companies considers that the existing abilities and qualification of its employees is insufficient for achieving their targets. The gap between desired level of capabilities and the existing capabilities of the human recourses should be narrowed. Therefore talent management (TM) concept is introduced in order to deal with the gap and reveal the required personnel profile. TM raises institutional awareness and is a supportive tool for HRM. The TM contributes to remove wastes of the companies and supports self-improvement of its employees. In other words the TM is a key of success about exploring abilities. The aim of this study is to propose a model for investigating competency level of employees and utilizing this information in obtaining a yield in an optimal level from employees' emotional and intellectual capabilities, and experiences. The level of perception and job-ability match of each employee is different. The tests implemented in companies for TM purposes are usually evaluated in crisp logic like black and white. In this study, a fuzzy logic approach is proposed in order to deal with uncertainty and vagueness in assessment of TM.
2009 7th IEEE International Conference on Industrial Informatics, 2009
Operations management in manufacturing systems mainly deals with five capabilities including moni... more Operations management in manufacturing systems mainly deals with five capabilities including monitoring, analysis, decision making, communications and controls, in which the group of capabilities run in a closed-loop cycle. There is no guarantee that these functions will be executed in the order expected. This necessitates a close control over the capabilities of manufacturing system in order to make sure that
Human-Computer Interaction. Novel Interaction Methods and Techniques, 2009
Swarm intelligence is the emergent collective intelligence of groups of simple autonomous agents ... more Swarm intelligence is the emergent collective intelligence of groups of simple autonomous agents which are autonomous subsystems that interact with their environment. This paper presents a performance evaluation system for swarm robots. The model proposed includes a set of performance assessment criteria and performance assessment and monitoring system. The proposed approach is developed for swarm robots developed for health system responsible for delivery, guidance, monitoring, recognition, and delivery which a project in European 6 th Framework Research Program and carried out by several European nations.

Robotics and Autonomous Systems, 2004
In this paper, fuzzy modeling for the control of basic oxygen furnace (BOF) processes is proposed... more In this paper, fuzzy modeling for the control of basic oxygen furnace (BOF) processes is proposed. BOF is a widely preferred and effective steel making method due to its higher productivity and considerably low production cost. Therefore, today almost 65% of the total crude steel production in the world is met by using the BOF method. Higher steel output at lower cost is one of the main objectives of modern steel making methods. In order to accomplish this objective, fuzzy modeling was employed in this study in order to control some variables related to the BOF process. Fuzzy modeling and control in BOF promise a solution to the strongly non-linear problems associated with the process, which have so far proven extremely difficult to be solved by conventional control methods. Data set was selected as inputs from the real empirical BOF data in an integrated steel plant based in Turkey. Although there were negligible deviations from the target values, most of the fuzzy results obtained using MATLAB-Fuzzy Logic Toolbox version 5.0 were found to be acceptable. As a result of the application of the proposed modeling, acceptable levels of compatibility were achieved compared to the empirical BOF data and targeted steel composition. The paper indicates how fuzzy logic would be effectively used for improved process control of BOF furnace in steel making industry.

Production Planning & Control, 2007
ABSTRACT This paper is modelled in details, and it describes an integrated MRP II agent system fo... more ABSTRACT This paper is modelled in details, and it describes an integrated MRP II agent system for use in a make-to-order manufacturing environment by demonstrating potential benefits on purchasing and manufacturing orders generated. MRP II activities were modelled in a multi-agent based system; the information exchanges and activities to occur within the system were identified and the system simulation was prepared by applying the Petri net method using the estimated operation times for these activities. Multi-agent systems were preferred for modelling due to the fact that these systems were intelligent software systems and they included discrete manufacturing systems as well as communication and software systems. Also, the Petri net system was preferred in simulation because it was one of the distributed artificial intelligence methods and used in the analysis of the status and information exchange in the software systems. The obtained results will provide information about the possible bottlenecks and interruptions to occur before implemented within a huge and complex system structure.
Uploads
Papers by CEMALETTİN KUBAT