Sürdürülebilir Kalkınma Amaçları
Yayınlar
- MakaleAçık Erişim2024An Evaluation of the logistics Performance Index Using the ENTROPY-based ORESTE Method
Mete, Süleyman; Özdemir, Ümit; Çıray, Deniz
Logistics performance measurement has become increasingly important for countries as the competitive environment has increased. For this purpose, the World Bank has begun publishing logistics performance index (LPI) reports. The LPI ranking of countries is determined by the experts’ scoring system. By re-analyzing this scoring and reevaluating it without the need for expert opinion, this study analyzed the evaluation of country rankings according to criteria weights from several different angles. This study aims to provide a detailed analysis of the World Bank’s 2023 report using the ENTROPY-based ORESTE method, which has not previously been used in LPI evaluation and provides a more accurate and robust approach to the research. Although several studies have explored this similar topic in the literature, using a new method and comparing the criteria weights by including them in the analysis gave the present study a broader perspective. LPI analysis is an important tool for assessing and improving a country’s competitiveness, and it can help investors compare logistics infrastructure and processes across countries. This can help stakeholders to better plan and make direct investments. Logistics researchers can use the LPI to examine sectoral and economic trends and forecast future developments. Furthermore, the LPI can be used in academia to train and raise awareness about assessment, logistics, and supply chain management programs. This is an important resource for training future logistics professionals and managers and providing policymakers and practitioners with a more refined tool for identifying areas for improvement and investment in logistics infrastructure.
AtıfTR Dizin3
İncele - MakaleAçık Erişim2019Doğal afet durumu için cbs tabanlı maksimum kapsama yerleşim modeli: tunceli örneği
Celik, Erkan; Özceylan, Eren; Mete, Süleyman; Özkan, Barış
Afet zamanlarında insani lojistik açısından afetzedelerin barınma yerlerine erişimi önemli bir problemdir. İnsani lojistik yönetiminin önündeki en büyük zorluklardan biri de fazla sayıdaki afetzedelerin koordinasyonudur. Özellikle, olay mahallindeki mekânsal verinin eksikliği etkin bir planlamanın önündeki en büyük engellerden biridir. Bu çalışmada, afet zamanlarında kullanılmak üzere potansiyel afetzedelerin ilgili barınaklara atanması için Coğrafi Bilgi Sistemi (CBS) tabanlı bir çözüm yaklaşımı önerilmiştir. Ulaşılan afetzede sayısını maksimize etmek için ArcGIS’in maksimum kapsama yerleşim modeli kullanılmış ve Tunceli ili üzerinde test edilmiştir. Tunceli şehir merkezindeki 2.121 adet binaya 31.076 kişi, nüfus olarak atanmış ve 5 barınma merkezi ile model çalıştırılmıştır. Daha sonra farklı sayıda barınma merkezi ve kapsama alanları altında senaryo analizleri gerçekleştirilmiş ve sonuçlar yorumlanmıştır. Elde edilen sonuçlar, önerilen modelin afetzedelerin barınma merkezlerine atanmasında etkin bir araç olduğunu göstermiştir.
AtıfOpenAlex4TR Dizin2İncele - MakaleYalnız künye2019Scopus SJRQ2An efficient algorithm for U-type assembly line re-balancing problem with stochastic task times
Serin, Faruk; Mete, Süleyman; Çelik, Erkan
Purpose: Changing the product characteristics and demand quantity resulting from the variability of the modern market leads to re-assigned tasks and changing the cycle time on the production line. Therefore, companies need re-balancing of their assembly line instead of balancing. The purpose of this paper is to propose an efficient algorithm approach for U-type assembly line re-balancing problem using stochastic task times. Design/methodology/approach: In this paper, a genetic algorithm is proposed to solve approach for U-type assembly line re-balancing problem using stochastic task times. Findings: The performance of the genetic algorithm is tested on a wide variety of data sets from literature. The task times are assumed normal distribution. The objective is to minimize total re-balancing cost, which consists of workstation cost, operating cost and task transposition cost. The test results show that proposed genetic algorithm approach for U-type assembly line re-balancing problem performs well in terms of minimizing total re-balancing cost. Practical implications: Demand variation is considered for stochastic U-type re balancing problem. Demand change also affects cycle time of the line. Hence, the stochastic U-type re-balancing problem under four different cycle times are analyzed to present practical case. Originality/value: As per the authors’ knowledge, it is the first time that genetic algorithm is applied to stochastic U-type re balancing problem. The large size data set is generated to analyze performance of genetic algorithm. The results of proposed algorithm are compared with ant colony optimization algorithm.
AtıfScopus19WoS17OpenAlex20
İncele - MakaleAçık Erişim2018Scopus SJRQ1An optimisation support for the design of hybrid production lines including assembly and disassembly tasks
Mete, Süleyman; Çil, Zeynel Abidin; Özceylan, Eren; Ağpak, Kürşad; Battaïa, Olga
The optimisation problems related to the assignment of tasks to workstations in assembly and disassembly lines have been largely discussed in the literature. They are known, respectively, as Assembly Line Balancing and Disassembly Line Balancing Problems. In this study, both types of task performed on the identical product are integrated in a common hybrid production system. Therefore, the logistic process is simplified and disassembly tasks can supply easier the assembly tasks with the required components. The considered production system has the layout of two parallel lines with common workstations. The product flow is conventional in the assembly line and reverse in the disassembly line. The paper provides a new mathematical model for designing such a hybrid system and an approximate approach based on ant colony optimisation for solving large-scale instances. The solution method is tested in a case study. The obtained results are compared with the solution provided by the design of two independent lines. The analysis of the results highlights the potential benefits of the hybrid production system.
AtıfScopus53OpenAlex51İncele - BildiriYalnız künye2017An efficient heuristic algorithm for solving robotic assembly line balancing problem
Çil, Zeynel Abidin; Mete, Süleyman; Özceylan, Eren
In the assembly system, robots provide to increase flexibility of the system and automation. The balancing robotic assembly line (RALB) problem consists two main works, which are not only assigning task to station, but also allocation robots in stations. Because each robots can perform different performance on the same tasks due to their capabilities. In this study, iterative beam search algorithm is developed to minimize cycle time. The performance of the algorithm outperforms other algorithm in the literature.
AtıfScopus2OpenAlex1İncele - BildiriYalnız künye2017Optimizing the location-allocation problem of bike sharing stations: A case study in gaziantep university campus
Özceylan, Eren; Mete, Süleyman; Çil, Zeynel Abidin; Drobne, S.; Zerovnik, J.; Zadnik Stirn, L.; Kljajic Borstar, M.
A growing number of cities are implementing bike-sharing programs to increase bicycle use. One of the key factors for the success of such programs is the location of bike stations in relation to potential demand. In this paper, potential locations of bike sharing stations in Gaziantep University campus are investigated to provide optimal utilization for users. To do so, first of all, 20 demand points and 20 potential bike stations are determined. Second, set covering mathematical model is handled to determine coverage capability of potential bike stations. Finally, P-center and P-median mathematical models are applied to set up potential stations and to assign demand points to the opened stations so that the total walking distance can be minimized. Computational experiments prove that our approach can find new potential bike stations which cover all demand points.
AtıfScopus5İncele - MakaleYalnız künye2017Scopus SJRQ1A beam search approach for solving type II robotic parallel assembly line balancing problem
Çil, Zeynel Abidin; Mete, Süleyman; Özceylan, Eren; Ağpak, Kürşad
In a robotic assembly line, a series of stations are arranged along a conveyor belt and a robot performs on tasks at each station. Parallel assembly lines can provide improving line balance, productivity and so on. Combining robotic and parallel assembly lines ensure increasing flexibility of system, capacity and decreasing breakdown sensitivity. Although aforementioned benefits, balancing of robotic parallel assembly lines is lacking – to the best knowledge of the authors- in the literature. Therefore, a mathematical model is proposed to define/solve the problem and also iterative beam search (IBS), best search method based on IBS (BIBS) and cutting BIBS (CBIBS) algorithms are presented to solve the large-size problem due to the complexity of the problem. The algorithm also tested on the generated benchmark problems for robotic parallel assembly line balancing problem. The superior performances of the proposed algorithms are verified by using a statistical test. The results show that the algorithms are very competitive and promising tool for further researches in the literature.
AtıfScopus56WoS48OpenAlex56İncele - BildiriYalnız künye2017A heuristic algorithm for assembly line balancing with stochastic sequence-dependent setup times
Çil, Zeynel Abidin; Mete, Süleyman; Özceylan, Eren; Diri Kenger, Zülal; Çil, Hande
Having analyzed studies on the assembly line balancing problem considering setup times, a few papers are observed. However, researches show that setup time plays an important role in total production time. Besides, in these studies, the setup times are assumed to be deterministic. Considering setup times to be deterministic decreases proximity of problem to real life application. Because the operation and setup times may vary in real applications due to human factors, machine breakdowns, lack of equipment and environmental factors. Therefore, in this study, assembly line balancing problem is investigated considering the sequence-dependent stochastic setup times. A heuristic approach based on COMSOAL is presented for the problem and it is seen that algorithm is effective for the problem.
AtıfScopus2İncele - MakaleYalnız künye2016Scopus SJRQ1A solution approach based on beam search algorithm for disassembly line balancing problem
Mete, Süleyman; Çil, Zeynel Abidin; Ağpak, Kürşad; Özceylan, Eren; Dolgui, Alexandre
The disassembly line balancing (DLB) problem is the process of allocating a set of disassembly tasks to an ordered sequence of workstations in such a way that optimizes some performance measures (e.g., cycle time, number of stations). Since DLB problems belong to the class of NP hard, many heuristic and meta-heuristic algorithms are applied to cope with the complexity of the DLB problems in order to obtain acceptable solutions in a reasonable amount of time. In this study, a beam search (BS) based approach for the DLB problem is proposed. Minimization of number of workstations is used as the performance measure. The proposed algorithm is compared with the optimal solutions of well-known real cases and generated test problems. The results indicate that the proposed approach based on BS is a very competitive and promising tool for further researches.
AtıfScopus70OpenAlex72İncele