Tunalı, Semra

Profile Picture
Profile URL
https://hdl.handle.net/20.500.14365/7045
Name Variants
Tunali, S
TUNALI, S
Tunali, Semra
Job Title
Email Address
semra.tunali@ieu.edu.tr
Main Affiliation
03.02. Business Administration
Status
Current Staff
Website
ORCID ID
0000-0002-4172-6479
Scopus Author ID
7004191746
Turkish CoHE Profile ID
BA7D86605059A18F
Google Scholar ID
nEYOdI4AAAAJ
WoS Researcher ID
AAM-5058-2021
Files
SemraTunali.jpg (5.06 KB)

Sustainable Development Goals

NO POVERTY1
NO POVERTY
0
Research Products
ZERO HUNGER2
ZERO HUNGER
0
Research Products
GOOD HEALTH AND WELL-BEING3
GOOD HEALTH AND WELL-BEING
0
Research Products
QUALITY EDUCATION4
QUALITY EDUCATION
0
Research Products
GENDER EQUALITY5
GENDER EQUALITY
0
Research Products
CLEAN WATER AND SANITATION6
CLEAN WATER AND SANITATION
0
Research Products
AFFORDABLE AND CLEAN ENERGY7
AFFORDABLE AND CLEAN ENERGY
0
Research Products
DECENT WORK AND ECONOMIC GROWTH8
DECENT WORK AND ECONOMIC GROWTH
0
Research Products
INDUSTRY, INNOVATION AND INFRASTRUCTURE9
INDUSTRY, INNOVATION AND INFRASTRUCTURE
5
Research Products
REDUCED INEQUALITIES10
REDUCED INEQUALITIES
0
Research Products
SUSTAINABLE CITIES AND COMMUNITIES11
SUSTAINABLE CITIES AND COMMUNITIES
0
Research Products
RESPONSIBLE CONSUMPTION AND PRODUCTION12
RESPONSIBLE CONSUMPTION AND PRODUCTION
1
Research Products
CLIMATE ACTION13
CLIMATE ACTION
0
Research Products
LIFE BELOW WATER14
LIFE BELOW WATER
0
Research Products
LIFE ON LAND15
LIFE ON LAND
1
Research Products
PEACE, JUSTICE AND STRONG INSTITUTIONS16
PEACE, JUSTICE AND STRONG INSTITUTIONS
0
Research Products
PARTNERSHIPS FOR THE GOALS17
PARTNERSHIPS FOR THE GOALS
0
Research Products
Documents

41

Citations

969

h-index

16

Go to Scopus profile
Documents

25

Citations

773

Go to WoS profile
Scholarly Output

24

Articles

17

Views / Downloads

132/31

Supervised MSc Theses

0

Supervised PhD Theses

1

WoS Citation Count

405

Scopus Citation Count

524

Patents

0

Projects

0

WoS Citations per Publication

16.88

Scopus Citations per Publication

21.83

Open Access Source

2

Supervised Theses

1

JournalCount
IFAC Proceedings Volumes (IFAC-PapersOnline)3
Internatıonal Journal of Productıon Research2
24th Mini EURO Conference on Continuous Optimization and Information-Based Technologies in the Financial Sector, MEC EurOPT 20102
Computers & Operatıons Research2
Engıneerıng Optımızatıon2
Current Page: 1 / 4

Scopus Quartile Distribution

Competency Cloud

GCRIS Competency Cloud

Filters

2010 - 2019222020 - 20251
Reset filters

Settings

Scholarly Output Search Results

Now showing 1 - 10 of 23
  • Thumbnail Image
    Article
    Citation - WoS: 44
    Citation - Scopus: 52
    A Tabu Search Approach for Buffer Allocation in Production Lines With Unreliable Machines
    (Taylor & Francis Ltd, 2011-02) Demir, Leyla; Tunali, Semra; Lokketangen, Arne
    The optimal allocation of buffers is an important research issue in designing production lines. In this study, a tabu search (TS) algorithm is proposed to find near-optimal buffer allocation plans for a serial production line with unreliable machines. The main objective is to maximize the production rate, i.e. throughput, of the line. The efficiency of the proposed method is also tested to solve buffer allocation problems with the objective of total buffer size minimization. To estimate the throughput of the line with a given specific buffer allocation, an analytical decomposition approximation method is used. The performance of the tabu search algorithm is demonstrated on existing benchmark problems. The results obtained by the TS algorithm are clearly encouraging, as the TS algorithm is much better than the other algorithms for all considered benchmark problems.
  • Thumbnail Image
    Conference Object
    Citation - Scopus: 2
    Simultaneous Balancing and Scheduling of Flexible Mixed Model Assembly Lines With Sequence Dependent Task Time Increments
    (Vilnius Gediminas Technical University, 2010) Ozturk, Cemalettin; Tunali S.; Hnich B.; Örnek, Mustafa Arslan
    General tendency in mixed model assembly line literature is to separate balancing and model sequencing decisions to different time frames. However, today's competitive market conditions force decision makers to respond quickly to changing demand patterns. Therefore, assembly line balancing and mixed model sequencing problems should be considered together. In this paper, we state the problem structure with sequence dependent task time increments and flexibility in task assignment. Furthermore, we compare the performance of two approaches which are proposed to solve the stated problem by using various problem instances. © Izmir University of Economics, Turkey, 2010.
  • Thumbnail Image
    Conference Object
    Citation - Scopus: 4
    A Comparison of Three Search Algorithms for Solving the Buffer Allocation Problem in Reliable Production Lines
    (IFAC Secretariat, 2013) Demir L.; Diamantidis A.; Eliiyi Türsel, Deniz; O'Kelly M.E.J.; Papadopoulos C.T.; Tsadiras A.K.; Tunali S.
    This paper investigates the performance of three search algorithms: Myopic Algorithm, Adaptive Tabu Search and Degraded Ceiling to solve the buffer allocation problem in reliable production lines. DECO algorithm is used to calculate throughput. This algorithm is a variant of a decomposition algorithm specifically developed to solve large reliable production lines with parallel machines at each workstation and exponentially distributed service times. The measures of performance used are the CPU time required and closeness to the maximum throughput achieved. The three search algorithms are ranked in respect to these two measures and certain findings regarding their performances over the experimental set are given. © IFAC.
  • Thumbnail Image
    Conference Object
    Citation - Scopus: 2
    Cyclic Scheduling of Flexible Mixed Model Assembly Lines
    (IFAC Secretariat, 2013) Ozturk, Cemalettin; Tunali S.; Hnich B.; Örnek, Mustafa Arslan
    Mixed model assembly lines are used to produce multiple copies of given minimum part set (MPS). Considering only one copy (cycle) of the MPS while solving the mixed-model balancing and scheduling problem yields suboptimal solutions since blocking and idle times of stations between repeated copies are ignored. Modeling and solving this problem in a cyclic manner can significantly overcome these inefficiencies and improve the throughput of the line. In this paper, after investigating the nature of the problem, we propose exact and heuristic methods for practical applications and evaluate their performances on various size test instances. © IFAC.
  • Thumbnail Image
    Article
    Citation - WoS: 12
    Citation - Scopus: 16
    Setting Order Promising Times in a Supply Chain Network Using Hybrid Simulation-Analytical Approach: an Industrial Case Study
    (Elsevier, 2011-10) Tunali, Semra; Ozfirat, Pinar Mizrak; Ay, Gulay
    Supply chain management (SCM) involves the management of material and information flow among the members of chain such as vendors, manufacturing plants and distribution centers. The main processes in supply chain are production planning, control, distribution and logistics. Effective management of all these processes provides the manufacturing companies great advantages in time based competition. In order to gain a competitive edge, firms must be able to deliver their products fast and on-time. This can be managed by better production planning, scheduling and due-date setting. This paper suggests a hybrid approach for setting realistic order due dates for a produce-to-order manufacturing company operating within a supply chain environment. The proposed hybrid approach combines mathematical and simulation modeling to bring together the advantages of both approaches. (C) 2011 Elsevier B. V. All rights reserved.
  • Thumbnail Image
    Review Article
    Citation - WoS: 23
    Citation - Scopus: 28
    A Review of the Current Applications of Genetic Algorithms in Mixed-Model Assembly Line Sequencing
    (Taylor & Francis Ltd, 2011-08) Akgunduz, Onur Serkan; Tunali, Semra
    A mixed-model assembly line (MMAL) is a type of production line which is capable of producing a variety of different product models simultaneously and continuously. The design and planning of such assembly lines involves several long-and short-term problems. Among these problems, determining the sequence of products to be produced has received considerable attention from the researchers. This problem is known as the Mixed-Model Assembly Line Sequencing Problem (MMALSP). An important issue that complicates the sequencing problem is its combinatorial nature. Typically, an enormous number of possible production sequences exist, even for relatively small problems, so that finding the optimal solution is usually impractical. Due to the complexity of the problem, in recent years, a growing number of researchers have employed genetic algorithms (GAs). This paper reviews the genetic algorithm based MMAL sequencing approaches presented in the literature and provides two hierarchical classification schemes to classify academic efforts according to both specifications of MMALSP and specifications of GA-based approaches. Moreover, future research directions have been identified and are suggested.
  • Thumbnail Image
    Article
    Citation - WoS: 45
    Citation - Scopus: 56
    An Adaptive Tabu Search Approach for Buffer Allocation Problem in Unreliable Non-Homogenous Production Lines
    (Pergamon-Elsevier Science Ltd, 2012-07) Demir, Leyla; Tunali, Semra; Eliiyi Türsel, Deniz
    The buffer allocation problem, i.e. how much buffer storage to allow and where to place it within the line, is an important research issue in designing production lines. In this study, a novel adaptive tabu search approach is proposed for solving buffer allocation problem in unreliable and non-homogeneous production lines. The objective is to maximize the throughput of the line, which is constrained by the capacity of each buffer space and also the total buffer capacity to allocate to these spaces. Besides proposing a new strategy to tune the parameters of tabu search adaptively during the search, an experimental study is carried out to select an intelligent initial solution scheme among three alternatives so as to decrease the search effort to obtain the best solutions. The performance of the proposed approach is evaluated by computational tests and very promising results are obtained. (C) 2011 Elsevier Ltd. All rights reserved.
  • Thumbnail Image
    Article
    Citation - WoS: 4
    Citation - Scopus: 4
    A Comparative Study of Hybrid Approaches for Solving Capacitated Lot Sizing Problem With Setup Carryover and Backordering
    (Inderscience Enterprises Ltd, 2016) Goren, Hacer Guner; Tunali, Semra
    The classical capacitated lot sizing problem is shown to be NP -hard for even a single item problem. This study deals with an extended version of this problem with setup carryover and backordering. To solve this computationally difficult lot sizing problem, we propose a number of hybrid meta -heuristic approaches consisting of genetic algorithms and a mixed integer programming -based heuristic. This MIP-based heuristic is combined with two types of decomposition schemes (i.e., product and time decomposition) to generate subproblems. Computational experiments are carried out on various problem sizes. We found that hybrid approaches employing only time decomposition scheme or combination of both time and product decomposition schemes in different forms outperform the other hybrid approaches. Moreover, we investigated the sensitivity of the two best performing approaches to changes in problem-specific parameters including backorder costs, setup times, setup costs, capacity utilisation and demand variability.
  • Thumbnail Image
    Article
    Citation - WoS: 15
    Citation - Scopus: 18
    Two Approaches for Solving the Buffer Allocation Problem in Unreliable Production Lines
    (Pergamon-Elsevier Science Ltd, 2013-10) Demir, Leyla; Tunali, Semra; Eliiyi Türsel, Deniz; Lokketangen, Arne
    This paper presents an integrated approach to solve the buffer allocation problem in unreliable production lines so as to maximize the throughput rate of the line with minimum total buffer size. The proposed integrated approach has two control loops; the inner loop and the outer loop. While the inner loop control includes an adaptive tabu search algorithm proposed by Demir et al. [8], binary search and tabu search are proposed for the outer loop. These nested loops aim at minimizing the total buffer size to achieve the desired throughput level. To improve the efficiency of the proposed tabu search, alternative neighborhood generation mechanisms are developed. The performances of the proposed algorithms are evaluated by extensive computational experimentation, and the results are reported. (C) 2013 Elsevier Ltd. All rights reserved.
  • Thumbnail Image
    Doctoral Thesis
    Anket Verileri Dayalı Ajan Tabanlı Simülasyon Modellemesi: Evsel İlaç Atığı Yönetimi için Bütünleşik Bir Yaklaşım
    (2025) Utma, Gizem Halil; Tunalı, Semra
    Küresel ilaç tüketimindeki hızlı artış, evsel ilaç atıklarının çevre ve halk sağlığı açısından yarattığı riskleri büyütmüştür. Bu tez, İzmir'deki hanelerin ilaçları saklama, bertaraf etme ve olası yeniden kullanma davranışlarını şekillendiren bireysel, yapısal ve bilgisel etmenleri incelemektedir. Çalışma iki aşamalı bir karma yöntem tasarımına dayanmaktadır. İlk aşamada, 401 hane ve 43 eczacıdan toplanan anket verileri lojistik regresyon ile analiz edilerek ilaç birikimi, kullanılmayan ilaçları evde tutma eğilimi, uygunsuz bertaraf ve yeniden kullanım niyetlerini etkileyen temel belirleyiciler ortaya konmuştur. Bu ampirik bulgular, ikinci aşamada bilgi müdahaleleri, eczacı rehberliği, toplama altyapısının güçlendirilmesi ve döngüsel ekonomi seçeneklerini içeren politika senaryolarını değerlendiren bir Etmen Tabanlı Modelleme ve Simülasyon (ABMS) çerçevesinin oluşturulmasında kullanılmıştır. Elde edilen sonuçlar, hanelerde oluşan ilaç fazlasının özellikle uzun süreli tedavilerde ortaya çıkan reçeteleme ve temin süreçlerinden kaynaklandığını göstermektedir. Simülasyon deneyleri, yalnızca bilgilendirme yapılmasının sınırlı bir etki yarattığını; etkili davranış değişimi için erişilebilir bir toplama altyapısının gerekli olduğunu ortaya koymaktadır. Eczacılar iade süreçlerini desteklemeye istekli olsa da yasal ve operasyonel sınırlamalar bu katkıyı kısıtlamaktadır. Ayrıca döngüsel ekonomiye yönelik uygulamalar, sıkı güvenlik gereklilikleri ve iade edilen ürünlerin sınırlı raf ömrü nedeniyle daralmaktadır. Sonuç olarak, evsel ilaç atıkların yönetimi konulu bu tez çalışması kapsamında yapılan simülasyon denemeleri, evsel ilaç atıklarının oluşmasını önleyici düzenlemeler yapma yaklaşımının, evsel ilaç atıklarının uygun bir şekilde imhası için düzenlemeler yapmaktan çok daha fazla etkili olacağını ortaya koymuştur. Bu yaklaşım; daha dengeli reçeteleme uygulamaları, yaygın ve etkin işleyen bir toplama ağı ve eczacıların sürece daha aktif katılımıyla önemli bir ölçüde desteklenebilir.