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Öğe 3PL Service Provider Selection with a Goal Programming Model Supported with Multicriteria Decision Making Approaches(GAZI UNIV, 2020) Ozcan, Evrencan; Ahiskali, MerveIn this study, third-party logistics (3PL) service provider selection problem is handled for a foreign trade company that exports the products with high quality level obtained by outsourcing, and who has problems regarding both cost, delivery quality and delivery time. In this direction, 7 criteria are determined for effective evaluation of the performance of the 5 logistics service providers the company is working for and the determination of the most suitable 3PL service provider according to the property of the orders (quantity, mode of conveyance, transportation channel, etc.). The priority levels of service providers are calculated by using these criteria in the combination of Analytic Hierarchy Process (AHP), and Technique for Order Preference by Similarity to Ideal Solution (TOPSIS). Then, a goal programming (GP) model that answers the question of which service provider to choose for which order, considering these priority values and the 12 system constraints and 5 objectives that the company encountered in real life is proposed. This model is the first one proposed in the literature for the selection of 3PL service providers for multimodal international transport with consistent results. The model is solved for the current 10 orders using the last 1-year data of the company and the most appropriate 3PL service provider combination is obtained. As a result of the solution of the problem with this methodology, an improvement is achieved about 7% for the rate of delivery on time, 33% for bid - bill consistency rate, and 29% for the problematic delivery rate.Öğe An Artificial Neural Network Model Supported With Multi Criteria Decision Making Approaches For Maintenance Planning In Hydroelectrıc Power Plants(POLISH MAINTENANCE SOC, 2020) Ozcan, Evrencan; Danisan, Tugba; Yumusak, Rabia; Eren, TamerPower plants are the large-scale production facilities with the main purpose of realizing uninterrupted, reliable, efficient, economic and environmentally friendly energy generation. Maintenance is one of the critical factors in achieving these comprehensive goals, which are called as sustainable energy supply. The maintenance processes carried out in order to ensure sustainable energy supply in the power plants should be managed due to the costs arising from time requirement, the use of material and labor, and the loss of generation. In this respect, it is critical that the fault dates are forecasted, and maintenance is performed without failure in power plants consisting of thousands of equipment. In this context in this study, the maintenance planning problem for equipment with high criticality level is handled in one of the large-scale hydroelectric power plants that meet the quintile of Turkey's energy demand as of the end of 2018. In the first stage, the evaluation criteria determined by the power plant experts are weighted by the Analytical Hierarchy Process (AHP), which is an accepted method in the literature, in order to determine the criticality levels of the equipment in terms of power plant at the next stage. In order to obtain the final priority ranking of the equipment in terms of power plant within the scope of these weights, Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) is used because of its advantages compared to other outranking algorithms. As a result of this solution, for the 14 main equipment groups with the highest criticality level determined on the basis of the power plant, periods between two breakdowns are estimated, and maintenance planning is performed based on these periods. In the estimation phase, an artificial neural network (ANN) model has been established by using 11-years fault data for selected equipment groups and the probable fault dates are estimated by considering a production facility as a system without considering the sector for the first time in the literature. With the plan including the maintenance activities that will be carried out before the determined breakdown dates, increasing the generation efficiency, extending the economic life of the power plant, minimizing the generation costs, maximizing the plant availability rate and maximizing profit are aimed. The maintenance plan is implemented for 2 years in the power plant and the unit shutdowns resulting from the selected equipment groups are not met and the mentioned goals are reached.Öğe Bakım ekiplerinin en kısa yoldan santrallara ulaşımı: hidroelektrik santral örneği(2021) Danışman, Tuğba; Ozcan, Evrencan; Eren, TamerElektrik santralları bir ülkenin enerji arzının karşılanmasına hizmet eden önemli tesislerdir. Elektrik enerji talebinin sürekli olması nedeniyle elektrik üretimininde kesintisiz olması gerekmektedir. Bu durum santralların uzun yıllar çalışmasından kaynaklı yıpranmasına yol açmaktadır. Üretiminsürdürülebilirliğinin sağlanması için santrallara bazı bakımların yapılması gerekmektedir. Bu nedenle santrallardaki arızaların giderilmesi ve bakımlarınyapılması için zaman önemli bir kısıttır. En kısa zamanda bakımlara başlanması sürdürülebilirlik noktasında önem arz etmektedir. Santraldaki mekanik,elektriksel ve elektronik tüm ekipmanların bakımı, uzman bakım ekipleri tarafından yapılmaktadır. Bu çalışmada Türkiye’deki elektrik enerjisi talebininyaklaşık %31,9’unu karşılayan Hidroelektrik Santrallar (HES) için uygulama yapılmıştır. Çalışmada bakım için görevlendirilen üç ekibin santrallara en kısayoldan ulaşması problemi ele alınmıştır. Türkiye’deki HES’ler arasında yıllık üretim miktarı yüksek olan on iki HES için çalışma yapılmıştır. Santrallardakibakımlarda görev alabilecek ekipler her santralda bulunmamaktadır. Çalışmaya dahil edilen on iki HES için bakımları yapabilecek sadece üç ekipbulunmaktadır. Bu nedenle bu üç ekibin santrallara en kısa yoldan ulaşmaları amaçlanmıştır. Problem çözümünde Floyd-Warshall algoritması kullanılmıştır.C tabanlı bir kod yardımı ile elde edilen çözümler sonucunda bakım ekiplerinin santrallara ulaşımında optimal sonuç veren en kısa yollar bulunmuştur.Öğe Decision making for promising quinoline-based anticancer agents through combined methodology(WILEY, 2020) Ozcan, Evrencan; Okten, Salih; Eren, TamerDuring the development of effective drugs for the treatment of cancer, one of the most important tasks is to identify effective drug candidates having maximum antiproliferation and minimum side effects. This paper considers the problem of selecting the most promising anticancer agents, showing inhibition at low IC50 concentration and low releasing lactate dehydrogenase percentage (cytotoxicity). Recently, we prepared quinoline analogs bearing different functional groups and determined their anticancer potential against the HeLa, C6, and HT29 cancer cell lines using different anticancer assays. Experimentally, seven quinoline derivatives consisting of different substituents were determined as promising anticancer agents. We propose a multicriteria recommendation method to identify the most promising anticancer agents against all tested cell lines with an accurate prediction algorithm according to the available input data. A multicriteria decision-making methodology (MCDM) was used for the solution of the relevant problem in this study. Both the experimental results and MCDM method indicated that 5,7-dibromo-8-hydroxyquinoline (2) and 6,8-dibromo-1,2,3,4-tetrahydroquinoline (6) are the most promising anticancer agents against the HeLa, HT29, and C6 cell lines.Öğe Deprem Sonrası Mobil Hizmet Tesisi Seçim Problemi için Çok Kriterli Bir Karar Modeli Önerisi(2020) Tezcan, Burcu; Özcan, Nermin Avşar; Ozcan, Evrencan; Eren, TamerAfetler meydana geldiği bölgede büyük zararlar vermekte ve toplumsal yaşamı kesintiye uğratmaktadır. Afet öncesinde zararların önlenmesi için alınması gereken tedbirler olduğu gibi sonrasında da afete maruz kalan bölgede kişilerin sağlık, barınma, beslenme, temizlik gibi ihtiyaçları karşılanmalıdır. Deprem gibi yüksek zararlara yol açan ve birçok alanı kullanılamaz hale getiren afetlerde kişilerin ihtiyaçlarının sağlanması için yeni tesislerin kurulması gerekmektedir. Bu aşamada, olası bir deprem öncesinde söz konusu tesislerin yerlerinin analitik bir temelle uygun olarak belirlenmesi, deprem sonrasında depremzedelere hizmetin etkin bir şekilde ulaşmasını sağlayacaktır. Kırıkkale, deprem üretme potansiyeli yüksek fay zonlarına mesafesi nedeniyle deprem tehlikesi yüksek olan bir şehirdir. Ayrıca, Türkiye’nin en önemli ve stratejik sanayi kuruluşlarının üretim tesislerini sınırları içinde bulundurmaktadır. Bunlara ek olarak, Ankara'ya en yakın il olan Kırıkkale, 46 ilin kesiştiği noktada yer almaktadır ve Kırıkkale-Ankara arasında kritik ve büyük sanayi tesisleri bulunmaktadır. Bu gerçekler, söz konusu yerlerde bir felaket için Kırıkkale'de kurulacak mobil hizmet tesislerini daha da önemli hale getirmektedir. Bu kapsamda bu çalışmada, literatürde ilk kez Kırıkkale ilinde mobil hizmet tesisi seçim problemi için çok kriterli bir karar modeli önerilmiştir.Öğe Dijkstra Algoritması Kullanılarak İpekYolu Koridorları Arasında En KısaUlaştırma Güzergâhının Belirlenmesi(2021) Özdemir, Sezgin; Sacar, Ömer; Ozcan, EvrencanÇin,çok taraflı ulaştırma politikaları ve 21. yy.İpekYolunu oluşturma hedefi kapsamında 2013 yılında tarihi bir adım atmıştır. “Kuşak ve Yol” sloganı ile Pekin’ den Londra’ ya ulaşan yeni bir ticaret yolunun projesini açıklamış ve güzergâh ülkelerine iş birliğiçağrısına bulunmuştur. Modern İpek Yolu olarak da adlandırılan bu proje; kara, deniz ve demiryolu taşımacılığının kullanılarak Çinilegüzergâhtaki 65’den fazla ülkeyi birbirine bağlanmayı, bu ülkelerde dengeli ve sürdürülebilir ekonomik kalkınmaları hedeflemektedir. Türkiye coğrafi ve jeopolitik konumusayesinde en önemli güzergâh ülkelerinden birisi olarak bu iş birliğindenen fazla beklentisi olan ülke durumundadır. Dolayısıyla Türkiye;demiryolu, karayolu, tüp geçitler ve boğaz köprüleri başta olmak üzere birçok önemli yatırıma imza atmıştır. Literatürde sosyal bilimler alanlarında İpekYolu ile ilgili birçok çalışma mevcuttur. Fakat bu çalışmadakonuya mühendislik uygulamaları yaklaşımıyla,tüm sosyal ve politik koşullardan bağımsız olarak optimal bir sonuç elde etme amacı güdülmüştür. Bu amaçla İpekyolu Koridorlarında Pekin’den Londra’ya ulaşan demiryolu ağı için toplam 26düğümden oluşan bir graf oluşturulmuşve en kısa yolun hesaplanması için Dijkstra algoritması Python programlama dilinde kodlanarak çözülmüştür.Modern İpek Yolu veya Orta Koridorolarak adlandırılan güzergâhın Pekin-Londra arası en kısa demiryolu güzergâhı olduğu sonucuna ulaşılmıştırÖğe En Kısa Yol Optimizasyonlarında Floyd-Warshall Algoritması: Lojistik Merkezler Örneği(2023) Keskin, Bekir; Ozcan, EvrencanLojistik merkezler taşımacılık, depolama, elleçleme, dağıtım, gümrükleme, ayrıştırma, ithalat, ihracat ve transit işlemler, sigorta ve bankacılık, altyapı hizmetleri, danışmanlık ve üretim vb. faaliyetlerin birbiriyle uyumlu bir şekilde yürütülmesine ve olası taşıma yöntemlerinin bir arada sunulmasına hizmet eden önemli tesislerdir. Yük talebinin sürekli olması nedeniyle yük taşımacılığının da kesintisiz, en kısa yoldan, yakıt tüketimi ve taşıma süresi açısından da optimal bir şekilde gerçekleştirilmesi gerekmektedir. Bu çalışmada yük trenlerinin lojistik merkezlere en kısa yoldan ulaşması problemi ele alınmıştır. Literatürde lojistik köylerle ilgili yazın taraması yapıldığında; lojistik merkezlerin, lojistik sektörüne yapmış olduğu katkılar incelenmiş, güçlü ve zayıf yönleri ortaya konmaya çalışılmış, etkin ve verimli çalışması hakkında önerilerle ilgili çalışmalar gözlemlenmiştir. Fakat bu çalışmada; konuya mühendislik uygulamaları yaklaşımıyla, ülke genelinde faaliyet gösteren on iki lojistik merkezin yanı sıra yapım ve ihale aşamasında yer alan yedi adet lojistik merkez de çalışma kapsamına dâhil edilerek, lojistik merkezler arasında güzergâh seçimi için en uygun sonuç elde etme amacı güdülmüştür. En kısa yol problemlerinin uygulama alanı genellikle bir şebekede/ağda yer alan noktalar arasında en kısa mesafenin belirlenmesi olup, çalışmada şebekedeki herhangi iki düğüm arasındaki en kısa yolun belirlemesi açısından Floyd-Warshall Algoritması tercih edilmiştir. Bu amaçla ulusal demiryolu ağı için toplam 33 düğümden oluşan bir çizge oluşturulmuş ve en kısa yolun hesaplanması için Floyd-Warshall algoritması Python programlama dilinde kodlanarak çözülmüştür ve toplam on dokuz adet lojistik merkez arasında en kısa yol/yollar tespit edilmiştir.Öğe Evaluation of the Difficulties in the Internet of Things (IoT) with Multi-Criteria Decision-Making(Mdpi, 2019) Uslu, Buse; Eren, Tamer; Gur, Seyda; Ozcan, EvrencanThe rapid development of technology has increased the desire of all to be on the Internet. The discovery that objects born of the Internet communicate with each other without external factors revealed, with the fourth industrial revolution, the concept of the Internet of Things (IoT). The communication of objects with each other means minimum labor and minimum cost for enterprises. Enterprises that want to transition to the Internet of Things face many difficulties. Identifying and correcting these difficulties can lead to both lost time and high cost. In this study, we investigated the difficulties encountered in the Internet of Things. As a result of the study, the degree of importance of the factors causing these difficulties was determined by multi-criteria decision-making methods and was presented to the enterprises. The main criteria, and the sub-criteria related to these main criteria, were determined. The main purpose of the enterprises transitioning to Industry 4.0 is the communication of things with each other. In this study, we aimed to determine which criteria caused difficulties in the transition to Industry 4.0. Then, the degree of importance of the criteria was determined using the analytic hierarchy process (AHP) and analytic network process (ANP) methods, in the multi-criteria decision-making. Through the study, we determined which criteria should be taken into consideration by the enterprises that want to transition to the Internet of Things. In this way, enterprises will be able to accelerate that transition by minimizing time and monetary loss.Öğe Evaluation of the hybrid renewable energy sources using sustainability index under uncertainty(Elsevier, 2021) Yurek, Yagmur Torul; Bulut, Merve; Ozyoruk, Bahar; Ozcan, EvrencanAsa result of continuous growth in population, efforts to meet increasing energy demand in a balanced way in the future as it is today, has led to the emergence of the sustainability concept. Sustainability is mainly considered with technical, economic, environmental and social aspects, hence the most effective instruments to ensure sustainability are renewable energy technologies which are interchangeably used for sustainability. Renewable energy problems regarding sustainability have inherently conflicting goals with a high degree of ambiguity and complexity. To address these problems, multi-criteria decision making (MCDM) approach serve best. Therefore, in this study, a MCDM approach integrating Pythagorean fuzzy sets (PFSs) in AHP-TOPSIS method combination was used to calculate the sustainability index and for ranking renewable energy technologies, hybrids and battery energy storage systems (BESSs) in Turkey. The sustainability index was handled in three main aspects, i.e., uninterrupted supply, economic supply and environmentally friendly supply. The results pointed out that hydro + solar and wind + solar hybrid alternatives have the highest sustainability index value while geothermal and biomass rank as the lowest two alternatives energy technologies. (C) 2021 Elsevier Ltd. All rights reserved.Öğe Goal Programming Approach For The Radiology Technician Scheduling Problem(Yildiz Technical Univ, 2019) Ozcan, Evrencan; Danisan, Tugba; Yumusak, Rabia; Gur, Seyda; Eren, TamerPopulation growth is led to an increase in demand in the health sector. Health services need to be met at the maximum level in the face of increasing demand. The number of patients per each health personnel in Turkey is too much. Considering this situation, it is seen that ensuring patient satisfaction is directly proportional to the satisfaction of the personnel. For this reason, some studies such as the positioning of polyclinics and hospitals encountered in health services, capacity planning and demand estimations, as well as the studies about the creation of study schedules of health personnel are also gained importance. In this study, it is aimed to provide the personnel satisfaction as much as possible. The Law No. 3153 on Radiology, Radionomy and Electrical Therapy and Other Physiotherapy Institutions published by the Ministry of Health of the Republic of Turkey, dated 19/4/1937, as well as the requirements of the Annex-1 of 21/1/2010, is considered. The scheduling problem for eight radiology technicians working in a private hospital in Ankara is discussed. A mathematical model is proposed using the goal programming method in order to assign the technicians to the four shifts as equally as possible. According to the researches, this is the first study which has the feature of radiology technicians and by considering government and hospital conditions as well as with staff requests, by application area.Öğe Hidroelektrik santrallarda bakım çizelgeleme için hibrid bir model önerisi(2020) Ozcan, Evrencan; Danışman, Tuğba; Eren, TamerBakım, endüstriyel işletmelerde üretim, personel ve malzeme ile eş zamanlı yönetilmesi gereken önemli bir prosestir. Bu önemli prosesin kritik aşamalarının başında bakım planlaması gelmektedir. Bakım planlaması için gerekli olan iki aşama bulunmaktadır. İlk aşama bakım stratejilerinin belirlenmesi ve ikinci aşama ise bakım çizelgelerinin oluşturulmasıdır. Bu çalışma, bakım planlamasının ilk adımını oluşturan bakım strateji seçiminin gerçekleştirildiği bir çalışmanın devamı olarak bakım çizelgelemesi için yapılmıştır. Bakım strateji seçimi için gerçekleştirilen ilk adımdaki çalışmada [5], Türkiye’deki büyük ölçekli bir hidroelektrik santralda yer alan 1330 elektriksel ekipman incelenmiş ve santral açısından kritiklik seviyesi belirlenmiştir. Çalışma sonucunda bir zaman çizelgesi doğrultusunda gerçekleştirilebilecek olan, periyodik bakım stratejisinin uygulanabileceği kritik elektriksel 7 ana ekipman grubu belirlenmiştir. Elde edilen bu sonuçlar bakım planlamasındaki bakım çizelgeleme aşamasını oluşturan bu çalışmada kullanılmıştır ve periyodik bakım stratejisinin uygulanabileceği bu kritik elektriksel 7 ana ekipman grubu için bakım çizelgesi oluşturulmuştur. Bakım çizelgeleme için yapılan bu çalışmanın ilk aşamasında santralın bir yıllık üretim tahmini Yapay Sinir Ağı (YSA) yöntemi ile gerçekleştirilmiş ve bu tahmin sonucunda elde edilen verilerden çalışma-bakım süreleri hesaplanmıştır. Tutarlı tahmin değerlerinin santralın bakım planlama gerçek ve gerekliliklerini yansıtan 0-1 Tam sayılı Programlama (TP) modelinde kullanılmasıyla, beş farklı periyodik bakım türü çizelgelenmiş ve santral işletme ve bakım gerçekleri ile tutarlı optimal bir bakım planı elde edilmiştir.Öğe How to build a state-of-the-art battery energy storage market? Challenges, opportunities, and future directions(Elsevier, 2024) Bulut, Merve; Ozcan, EvrencanThe leading role of the recent developments in critical energy storage technologies that will ensure universal energy access in a balanced and reliable way belongs to battery energy storage systems (BESSs), which are a robust stakeholder. The fact that these are regulated instruments in electricity markets, due to their technical nature when equipped with solid policies, can serve not only the purpose of carbon neutrality and net zero but also restrain the problems of warming and climate change. This study, which is an answer to the questions of how modern policies affect the markets and how the markets shape the policies, explores the strategic balance of BESSs in the role of price taker/price maker when it comes to market effect. Strategic balance encompasses not only the commercial maneuvers of policymakers within the liberalized electricity market, but also the decay of electrochemical accumulations throughout their practical life cycles, considering the utilization of industrial symbiosis practices to promote a circular economy for the disposal of end-of-life (EoL) electrochemical stacks. In this respect, this study, which establishes the policy-market-symbiosis triangle for BESSs, is the first to examine this perspective in the literature to the best of our knowledge. Each corner of the triangle systematically considers the role of policies, market dynamics, and symbiotic relationships in directing the deployment and use of these modern systems towards a common goal.Öğe In-Vitro Anticancer and Antibacterial Activities of Brominated Indeno[1,2-b]qinoline Amines Supported with Molecular Docking and MCDM**(Wiley-V C H Verlag Gmbh, 2021) Aydin, Ali; Okten, Salih; Erkan, Sultan; Bulut, Merve; Ozcan, Evrencan; Tutar, Ahmet; Eren, TamerThe present study describes mono substituted indeno[1,2-b]quinolines (3 a-c and 5) have much more antiproliferative potentials than positive controls against A549, HeLa, MCF7 and Hep3B cell lines (IC50 values 1.1-29.6 mu g/mL) and show similar cytotoxicity (14.3 % to 19.8 %) to cells such as controls. Moreover, the mono substituted indeno[1,2-b]quinoline amines (3 a-c and 5) exhibit significant antimicrobial activity with MIC values between 15.62 mu g/mL and 250 mu g/mL. The compounds can also bind to DNA in the groove binding mode with a binding constant range of 1.1x10(3)-1.1x10(5) M-1. The anticancer and antibacterial properties of compounds were confirmed with the molecular docking simulation for their pharmacokinetic. As a result, the preliminary experimental data and a multi-criteria decision-making methodology (MCDM) indicated that the mono substituted indeno[1,2-b]quinoline amine derivatives, especially 3 a and 5, exhibit effective pharmacological properties. parameters and their interaction with related cells at the molecular level.Öğe Integration of Battery Energy Storage Systems into Natural Gas Combined Cycle Power Plants in Fuzzy Environment(Elsevier, 2021) Bulut, Merve; Ozcan, EvrencanThe increasing share of renewable energy sources in the grid has created the need for operational flexibility for natural gas combined cycle power plants (NGCCPPs) that offer high thermal efficiency and ease of operation. However, battery energy storage technologies (BESSs), which eliminate the time and ratio imbalance between energy supply and demand, will be effective solutions that can increase plant flexibility when integrated with NGCCPPs. This integration is a decision problem with high uncertainty and complexity evaluated by grid stakeholders. For this reason, firstly, the operational goals of the power plants have been prioritized in terms of BESSs. At this phase, the combination of Pythagorean Fuzzy AHP and Pythagorean Fuzzy TOPSIS methods was used. Afterwards, to pose a sustainable projection under the mentioned operational goals, which is the main purpose of the study has been started to the phase of ranking BESSs (lead-acid, lithium-ion, vanadium redox flow battery, sodium-nickel chloride, sodium-sulfur) under different conditions. By this means, evaluating the BESSs for different application purposes, rationalizing the high uncertainty in both the energy sector and electricity markets at the same time with the proposed hierarchical model will provide an important projection to the literature. The results of the proposed methodology show that lithium-ion batteries can be an effective replacement technology alternative for NGCCPPs, given their economic benefits and technological capabilities. Another result is that the scalability of BESSs can be used for different operational goals in the power plants. This also can allow the establishment of a hybrid BESS facility.Öğe KISIT PROGRAMLAMA VE HEDEF PROGRAMLAMA ENTEGRASYONU İLE VARDİYA ÇİZELGELEMESİ: HİDROELEKTRİK SANTRAL UYGULAMASI(2020) Ozcan, Evrencan; Alakaş, Hacı Mehmet; Yelek, Ayşe; Eren, TamerToplumsal hayatın gereksinim duyduğu enerjinin kesintisiz, güvenilir, zamanında, temiz ve ekonomik yollarla üretilmesi ve en uygun fiyatlarla arz edilmesi olarak tanımlanan sürdürülebilir enerji arzı, gelişmiş ve gelişmekte olan ülkeler için büyük önem taşımaktadır. Dünya enerji karışımındaki yaklaşık beşte birlik payı ile en gelişmiş yenilebilir enerji teknolojisi olan hidroelektrik santraller ise, sürdürülebilir enerji arzının tüm dünyada olduğu gibi Türkiye’de de sağlanması açısından kritik öneme sahiptir. Hidroelektrik santrallerde tüm elektrik üretim tesislerinde olduğu gibi vardiyalı bir çalışma programı bulunmaktadır. Bu sürekli üretim tesislerinde gerçekleşebilecek olan uzun süreli arızaların engellenmesini ve üretimin kesintisiz bir şekilde devam edebilmesini sağlayan personellerin işletmenin istekleri ve yasal yükümlülükler doğrultusunda analitik olarak çizelgelenmesi önemli bir husustur. Buradan hareketle bu çalışmada, bir hidroelektrik santralde çalışan personellerin çizelgelenmesi problemi ele alınmıştır. Problemin çözümü için kısıt programlama ve hedef programlamanın entegre edildiği model literatürde ilk defa önerilmiştir. Gerçek veriler ile oluşturulan bu entegre modelin çözümü neticesinde 3 vardiyada çalışan 28 personel için 31 günlük optimal bir çizelge elde edilmiştir. Elde edilen yeni çizelgede vardiya ekipleri arasında adaletli ve dengeli bir atama yapılarak işletmenin istekleri ve personelin memnuniyeti sağlanmıştır.Öğe Multi-objective optimization of energy system with battery storage - A case study of Turkey(Elsevier, 2024) Yurek, Yagmur Torul; Ozyoruk, Bahar; Ozcan, EvrencanTransition to clean energy sources is currently a paramount concern, necessitating the development of a robust long-term energy strategy and effective resource planning. This planning must encompass not only the economic and technical attributes of renewable energy resources but also their societal and environmental impacts, as these aspects significantly influence the feasibility of sustainable energy plans. To address these challenges, this study explores the application of multi -objective optimization methods, known for their ability to simultaneously consider multiple objectives. In this research, we propose a multi -objective linear programming model to allocate electricity generation among a range of 13 power plant alternatives for the planning horizon spanning 2022 to 2030. The selection of these alternatives incorporates two -source hybrid systems and battery storage systems due to their contributions to system stability and flexibility. The findings of this study indicate that wind and solar resources hold the largest share of electricity generation at 34% followed closely by hydro contributing to 30% of the generation. Notably, storage systems, particularly battery energy storage systems, are ranked lower due to their lower scores in socio-political and sustainability indices, as well as higher unit generation costs. It is worth noting that battery energy storage systems represent a relatively novel technology in Turkey, with potential for improving system reliability in the future, even though the majority of generation currently stems from existing and hybrid facilities.Öğe N-function Heterocycles as Promising Anticancer Agents: A Case Study with a Decision Model in a Fuzzy Environment(Bentham Science Publ Ltd, 2024) Bulut, Merve; Okten, Salih; Ozcan, Evrencan; Eren, TamerObjective This study aimed to evaluate the data according to five accepted criteria for the effects of twenty promising anticancer agents on five different cancer types and determine the most effective compounds for further in vitro and in vivo studies with a multi-criteria decision-making method (MCDM), which rationalizes decision making in a fuzzy environment to avoid the high cost and time requirements of further preclinical and clinical studies.Methods Within the scope of the study, the weights of the five criteria were evaluated with the Pythagorean Fuzzy Analytic Hierarchy Process (PFAHP), which is one of the multi-criteria decision-making methods, and a comparison was made with the criteria weights obtained as a result of the Complex Proportional Assessment (COPRAS) method. Moreover, the effects of criteria weights calculated with PFAHP on evaluating alternatives were analyzed using different scenarios.Results Experimentally, twenty N-heterocyclic quinoline derivatives with different substituents were identified as promising anticancer agents. In this study, the multi-criteria decision-making (MCDM) model was proposed to identify the most promising anticancer agents against all tested cell lines. Both the experimental and model results indicated that 20, 17, 19, and 7 are the most promising anticancer agents against the A549, HeLa, Hep3B, HT29, and MCF7 cell lines. Moreover, different scenarios were generated and analyzed to prove the consistency of the proposed methodology.Conclusion MCDM strongly suggests that compounds 20, 17, 19, and 7 can be further investigated for in vivo studies.Öğe Optimization of electricity transmission by Ford-Fulkerson algorithm(Elsevier, 2021) Bulut, Merve; Ozcan, EvrencanThe demand for energy is constantly increasing worldwide with the increase in population, globalization, and developing technology. The energy generated in the sustainability axis in the power plants is transmitted to the substations in the consumption regions and from there to the interconnected system with electricity transmission lines with available transfer capabilities (ATC). This shows the necessity of sustainability in transmission as well as generation. Although there are many studies in the literature to calculate and improve the ATCs of the lines, the cases of handling the transmission lines separately and ensuring the maximum energy flow in the whole network were not considered. In this context, an optimal solution approach to the problem is presented with the Ford-Fulkerson algorithm, which is often preferred in the applications of maximum flow problems due to its advantages but used for the first time in electricity transmission in this study. The proposed approach has been applied to the eleven-nodes network with a source node located in the generation zone and a target node located in the target, and the highest possible amount of energy flow was calculated considering the time complexity status of the algorithms in programming languages. (C) 2021 Elsevier Ltd. All rights reserved.Öğe Personnel Selection with Multi-Criteria Decision Making Methods in the Ready-to-Wear Sector(Univ Osijek, Tech Fac, 2022) Danisan, Tugba; Ozcan, Evrencan; Eren, TamerThe selection of personnel to be recruited for businesses is a significant problem. This study discusses the problem of selecting a person to be hired to use a machine with various specific features in a textile factory. It was aimed to select the most suitable candidate for the job. MCDM methods were used to make an analytical selection away from subjectivity. In this study, real-life business procedures were performed. The Weighted Scoring (WS) method was used for preselection. Important criteria weights for the factory were determined with the Analytical Hierarchy Process (AHP) method. Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) and Preference Ranking Organization Method for Enrichment Evaluations (PROMETHEE) methods were used to make a correct selection among the candidates. The most suitable candidate for the job was selected with the methodology followed. The study differs from other studies in the literature with the evaluation criteria, combination of methods, the methodology followed.Öğe Post-Disaster Temporary Storage Location Selection and Multi-Vehicle Vehicle Routing Application: An Case in Kirikkale Province(Gazi Univ, 2023) Tezcan, Burcu; Alakas, Haci Mehmet; Ozcan, Evrencan; Eren, TamerIt is unclear when and where disasters will occur. Therefore, both social life is interrupted and it harms the environment. In addition, after the disaster, people's needs such as food, shelter and cleaning should be met quickly and regularly. In order to meet the needs of people in disasters that cause great damage such as earthquakes and make many places unusable, the temporary warehouse should be located. Therefore, the locations of the temporary storage should be determined using appropriate analytical methods before an earthquake occurs. Kirikkale is a city with high probability of earthquakes due to its distance to fault zones. This, as well as production facilities are located within the boundaries of Turkey's major strategic industry. The fact that 43 provinces are the intersection point, especially its proximity to Ankara and the large industrial establishments located between Ankara increase the importance of the temporary warehouse to be located in Kirikkale in a possible earthquake outside Kirikkale. In this study, the problem of temporary warehouse location selection in Kirikkale province has been addressed in 3 stages. In the first stage, four alternative districts were compared, in the second stage, six alternative locations were compared by using multi-criteria decision-making methods. After determining the location of the temporary warehouse, in the third stage, the routes through which the food distribution will be distributed were determined with four different scenarios. In this study, a integrated approach for warehouse location selection and distribution planning is proposed to the literature.
