Bulut, Önder
Loading...
Name Variants
Job Title
Doç.Dr.
Email Address
Main Affiliation
01.01.09.03. Endüstri Mühendisliği Bölümü
Status
Current Staff
Website
ORCID ID
Scopus Author ID
Turkish CoHE Profile ID
Google Scholar ID
WoS Researcher ID
Sustainable Development Goals
1NO POVERTY
0
Research Products
2ZERO HUNGER
0
Research Products
3GOOD HEALTH AND WELL-BEING
0
Research Products
4QUALITY EDUCATION
0
Research Products
5GENDER EQUALITY
0
Research Products
6CLEAN WATER AND SANITATION
0
Research Products
7AFFORDABLE AND CLEAN ENERGY
0
Research Products
8DECENT WORK AND ECONOMIC GROWTH
0
Research Products
9INDUSTRY, INNOVATION AND INFRASTRUCTURE
3
Research Products
10REDUCED INEQUALITIES
0
Research Products
11SUSTAINABLE CITIES AND COMMUNITIES
1
Research Products
12RESPONSIBLE CONSUMPTION AND PRODUCTION
0
Research Products
13CLIMATE ACTION
0
Research Products
14LIFE BELOW WATER
0
Research Products
15LIFE ON LAND
0
Research Products
16PEACE, JUSTICE AND STRONG INSTITUTIONS
0
Research Products
17PARTNERSHIPS FOR THE GOALS
0
Research Products
Documents
35
Citations
213
h-index
8
Documents
27
Citations
165
Scholarly Output
44
Articles
14
Views / Downloads
0/6
Supervised MSc Theses
11
Supervised PhD Theses
2
WoS Citation Count
92
Scopus Citation Count
135
Patents
0
Projects
1
WoS Citations per Publication
2.09
Scopus Citations per Publication
3.07
Open Access Source
7
Supervised Theses
13
| Journal | Count |
|---|---|
| International Symposium for Production Research ISPR 2023 | 3 |
| An International Journal of Optimization and Control: Theories & Applications (IJOCTA) | 2 |
| IEEE Congress on Evolutionary Computation (CEC) | 2 |
| 22nd International Symposium for Production Research ISPR 2022 | 2 |
| 4th International Conference on Intelligent and Fuzzy Systems (INFUS) | 2 |
Current Page: 1 / 5
Scopus Quartile Distribution
Quartile distribution chart data is not available
Competency Cloud
44 results
Scholarly Output Search Results
Now showing 1 - 10 of 44
Conference Object A Comparative Study of Artificial Intelligence Based Methods for Abnormal Pattern Identification in SPC(SPRINGER INTERNATIONAL PUBLISHING AG, 2022) Umut Avci; Onder Bulut; Ayhan Ozgur Toy; Toy, Ayhan Ozgur; Bulut, Onder; Avci, Umut; C Kahraman; AC Tolga; SC Onar; S Cebi; B Oztaysi; IU SariStatistical process control techniques have been used to detect any assignable cause that may result in a lower quality. Among these techniques is the identification of any abnormal patterns that may indicate the presence of an assignable cause. These abnormal patterns may be in the form of steady movement in one direction i.e. trends, an instantaneous change in the process mean i.e. sudden shift, a series of high observations followed by a series of low observations i.e. cycles. As long as we can classify the observed data the decision maker can decide on actions to be performed to ensure quality standards and planning for interventions. In identification of these abnormal patterns rather than relying on human element intelligent tools have been proposed in the literature. We attempt to provide a comparative study of various classification algorithms used for pattern identification in statistical process control. We specifically consider six different types of patterns to classify. These different types are: (1) Normal (2) Upward trend (3) Downward trend (4) Upward shift (5) Downward shift (6) Cyclic. A recent trend in classification is to use deep neural networks (DNNs). However due to the design complexity of DNNs alternative classification methods should also be considered. Our focus on this study is to compare traditional classification methods to a recent DNN solution in the literature in terms of their efficiencies. Our numerical study indicates that basic classification algorithms perform relatively well in addition to their structural advantages.Article Analysis of make-to-stock queues with general processing times and start-\rup and lost sales costs(2022) Önder Bulut; Sinem Özkan; Özkan, Sinem; Bulut, ÖnderWe consider a make-to-stock environment with a single production unit that\rcorresponds to a single machine or a line. Production and hence inventory are\rcontrolled by the two-critical-number policy. Production times are independent\rand identically distributed general random variables and demands are generated\raccording to a stationary Poisson process. We model this production-inventory\rsystem as an M/G/1 make-to-stock queue. The main contribution of the study is to\rextend the control of make-to-stock literature by considering general production\rtimes lost sales and fixed production costs at the same time. We characterize the\rlong-run behaviour of the system and also propose a simple but very effective\rapproximation to calculate the control parameters of the two-critical-number\rpolicy. An extensive numerical study exhibits the effects of the production time\rdistribution and the system parameters on the policy control levels and average\rsystem cost.Article Citation - WoS: 1Citation - Scopus: 6Control of make-to-stock production systems with setup costs(GAZI UNIV FAC ENGINEERING ARCHITECTURE, 2020) Sinem Ozkan; Onder Bulut; Özkan, Sinem; Bulut, ÖnderThis study considers the joint control of production and inventory in a Markovian make-to-stock environment with parallel production lines production start-up costs several customer classes and lost sales. At the production completion and demand arrival epochs there are two types of decisions. The first is the determination of the number of lines that should be active (producing) and the second one is whether to satisfy an arriving demand. Especially at the states where inventory position is low it would be more economical to reject the arriving demands of lower priority classes and reserve on-hand stock for future demands of more valuable classes. This study contributes to the control literature of make-to-stock systems with the simultaneous consideration of fixed production costs multiple lines and several customer classes. The dynamic programming formulation of the system which we model as a Markov Decision Process is developed by defining a two-dimensional system state vector. The model is solved with the value iteration algorithm. It is shown with the numerical examples that the optimal production and stock rationing policies have dynamic structures. Due to the dynamic nature of the optimal policies we also propose easy-to-apply and well-performing alternative policies. The proposed production policy is an extended version of the twocritical-number policy which is frequently considered in the literature. The proposed rationing policy is a dynamic one that considers the value of outstanding production orders in addition to inventory level.Article Citation - WoS: 3Citation - Scopus: 4Control of M/Cox-2/s make-to-stock systems(RAMAZAN YAMAN, 2020) Ozgun Yucel; Oender Bulut; Yücel, Özgün; Bulut, ÖnderThis study considers a make-to-stock production system with multiple identical parallel servers fixed production start-up costs and lost sales. Processing times are assumed to be two-phase Coxian random variables that allows us to model the systems having rework or remanufacturing operations. First the dynamic programming formulation is developed and the structure of the optimal production policy is characterized. Due to the highly dynamic nature of the optimal policy as a second contribution we propose an easy-to-apply production policy. The proposed policy makes use of the dynamic state information and controlled by only two parameters. We test the performance of the proposed policy at several instances and reveal that it is near optimal. We also assess the value of dynamic state information in general by comparing the proposed policy with the well-known static inventory position based policy.Master Thesis Ortak teslim tarihli ve ağırlıklı toplam erkenlik, gecikme, birim erkenlik ve sabit atama maliyetli paralel makine çizelgeleme(2025) Yeginoğlu, Berkin; Toy, Ayhan Özgür; Bulut, ÖnderThis thesis addresses the parallel machine scheduling problem with a common due date, aiming to minimize total weighted earliness, tardiness, unit earliness and fixed assignment costs. The objective function introduces a novel cost structure by extending traditional earliness and tardiness penalties with two additional components: (i) unit earliness costs, and (ii) fixed machine assignment costs. These extensions are motivated by practical considerations in production systems, such as inventory holding costs, quality preservation, and work-in-process (WIP) stocking costs. A mixed-integer linear programming (MILP) formulation is proposed to optimally solve small-sized instances and serve as a benchmark for evaluating heuristic methods. Due to the NP-hard nature of the problem, exact methods become computationally infeasible for larger instances. To address this, a problem-specific Genetic Algorithm (GA) is developed, incorporating a tailored solution representation, one-point crossover and cusromized mutation operators, and the revised V-shaped scheduling property to guide sequencing decisions. A comprehensive experimental study is implemented to assess the GA's performance across various problem sizes and parameter settings. GA parameters are tuned through preliminary testing to ensure a problem adaptive convergence behavior. Extensive computational experiments are conducted using both benchmark problems from the literature and newly generated datasets. Results indicate that the proposed GA consistently achieves near-optimal solutions in significantly less time than the MILP model, especially in larger instances. The algorithm demonstrates strong performance in terms of solution quality and computational efficiency making it a promising approach for solving complex scheduling problems in practical manufacturing environments.Master Thesis Özdeş paralel makinelerde atama ve çizelgeleme problemi(2013) Kızılay, Damla; Budak, Mehmet Emin; Taşgetiren, Mehmet Fatih; Bulut, ÖnderThis paper presents a discrete artificial bee colony algorithm to solve the assignment and scheduling problem in DYO painting company. In the DYO Paint Company, there are three types of filling machines groups: automatic, semiautomatic and manual. In each group, there are several numbers of identical machines. The problem is to first assign these filling production orders to machine groups. Then, these filling production orders on each machine groups should be scheduled on identical parallel machines to minimize the sum of makespan and total tardiness. We also develop a traditional genetic algorithm and variable neighborhood search algorithm to solve the same problem. The computational results show that the VNS algorithm slightly outperforms the GA and DABC on set of benchmark problems we generated.Conference Object Citation - WoS: 5Citation - Scopus: 5A Discrete Artificial Bee Colony Algorithm for the Assignment and Parallel Machine Scheduling Problem in DYO Paint Company(IEEE, 2014) Damla Kizilay; M. Fatih Tasgetiren; Onder Bulut; Bilgehan Bostan; Kizilay, Damla; Tasgetiren, M. Fatih; Bulut, Onder; Bostan, BilgehanThis paper presents a discrete artificial bee colony algorithm to solve the assignment and parallel machine scheduling problem in DYO paint company. The aim of this paper is to develop some algorithms to be employed in the DYO paint company by using their real-life data in the future. Currently in the DYO paint company, there exist three types of filling machines groups. These are automatic semiautomatic and manual machine groups where there are several numbers of identical machines. The problem is to first assign the filling production orders (jobs) to machine groups. Then filling production orders assigned to each machine group should be scheduled on identical parallel machines to minimize the sum of makespan and the total weighted tardiness. We also develop a traditional genetic algorithm to solve the same problem. The computational results show that the DABC algorithm outperforms the GA on set of benchmark problems we have generated.Master Thesis Paralel makine çizelgeleme: Konfeksiyon endüstrisinde bir uygulama(2023) Çini, Gülce; Toy, Ayhan Özgür; Bulut, ÖnderBu çalışmada, giyim endüstrisine ait bir firmanın dikim aşaması incelenmiş olup, çizelgeleme problemi terminolojisi kullanılarak altı farklı tam sayılı çizelgeleme problemi formülasyonu sunulmuştur. Makinelerin aynı hız ve özelliklere sahip olması nedeniyle, sistemin özdeş paralel makine çizelgeleme problemine uygun olduğu tespit edilmiştir. İlk model, basit bir maksimum tamamlanma süresi (makespan) minimizasyonu olarak verilmiştir. Ardından, sıraya bağlı kurulum süreleri, işe hazır olma tarihleri, makine uygunluğu ve iş bölme gibi kısıtlamalar eklenerek problem genişletilmiştir. Probleme, işlerin teslim tarihleri de eklenerek amaç fonksiyonu toplam erken ve gecikmelerin minimizasyonu olarak belirlenmiştir. Geliştirilen son model bir genetik algoritma ile birleştirilmiştir. Ancak, gerçek hayattaki problemlerde, operatör öğrenme eğrisi, yorgunluğu ve makine bakım gereksinimleri gibi faktörler nedeniyle bir işin işlem süresi değişkenlik gösterebilmektedir. Aynı şekilde kurulum süreleri de insan ve teknik faktörlere bağlı olarak değişebilmektedir. Bu faktörler nedeniyle problem bulanık işlem süreleri ve bulanık kurulum süreleri ile problemin bir uzantısı olarak verilmiştir. Bu yaklaşım, bir rastgele arama algoritması, bir Monte Carlo simulasyonu, aracılığıyla karşılaştırılmıştır. Geliştirilen modeller OPL Cplex ile doğrulandıktan sonra çeşitli veriler yardımı ile optimum çözümün sonuçları ve algoritmaların çözüm sonuçları karşılaştırılmıştır ve önerilen metodolojilerin çözüm kaliteleri sunulmuştur.Article Citation - WoS: 5Citation - Scopus: 3Production control problem for multi-product multi-resource make-to-stock systems(GROWING SCIENCE, 2024) Sinem Ozkan; Onder Bulut; Mehmet Cemali Dincer; Özkan, Sinem; Bulut, Önder; Dinçer, Mehmet CemaliMost of today's production systems are working with parallel production resources to increase throughput rate due to the increase in high variability in demand and product mix. Effective control and performance evaluation of such systems is of paramount importance to minimize production and inventory-related costs. We examine a production-inventory system featuring parallel production resources capable of producing various products. In many industries such as automotive white goods electronics and paint multiple/parallel production resources are widely used to produce the ideal amount and satisfy incoming demands for distinct products. In this study shortage cost is not restricted to only one type and both lost sales and backordering cases are analyzed. In order to analyze the optimal production policies' behavior we initially formulate dynamic programming models for both lost sales and backordering systems treating them as Markov Decision Processes. Subsequently we solve these models using the value iteration algorithm. Given the challenges posed by the curse of dimensionality in the value iteration algorithm we suggest alternative heuristic production policies. These policies extend the existing ones described for multi-item single-resource make-to-stock (MTS) systems to accommodate multiple resources. We construct simulation models to assess the efficacy of the heuristic policies conducting comparisons of their performance against both the optimal policy and among one another. To the best of our knowledge there has been no exploration of scenarios involving multiple production resources concurrently manufacturing distinct products in a MTS environment. Hence this study serves as an extension to the examination of multi-item multi-production resource MTS systems. (c) 2024 by the authors, licensee Growing Science CanadaMaster Thesis Paralel üretim kanallı ve hazırlık maliyetli stoğa-üretim sistemlerinin kontrolü(2016) Özkan, Sinem; Bulut, ÖnderThis study considers production and inventory control problems for a make-to-stock queue with production setup costs, several customer classes and lost sales. At any system state, production decision is to specify whether to activate new production channels or to continue with the currently active ones. If the decision is to activate new channels, a fixed/setup cost is incurred per channel. At the decision epochs where the system experiences demand from any customer class, the controller should also decide whether to satisfy the arriving demand or to reject it. The literature of the control of make-to-stock queues is extended by considering fixed system costs and multiple servers at the same time. Firstly, the structure of the optimal production and rationing policies are characterized and then new/alternative policies that have well-defined structures and are easier to apply are proposed. Numerical and theoretical studies are carried out to assess the performances of the proposed policies. The expected average cost of the optimal production policy for the single-server make-to-stock queue is obtained conducting a renewal analysis.
