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All elements in the supply chain, from the field to the delivery of fresh fruits and vegetables to the consumer, are of great importance to humanity. Different decision makers occur in the supply chain of delivering fresh fruits and vegetables to consumers in our country and the world. Considering the situation in our country, there are steps to deliver the products from the field to the wholesale markets, from the wholesale markets to the markets/grocers and from the markets/grocers to the consumers in the process from the production to the consumer. In this study, the wholesale markets brokers, market/grocery managers and consumers who have a say in the supply of fresh fruit and vegetable products, product selection approaches in the fields, selection approaches in wholesale markets and selection approaches in the grocery stores were investigated, respectively. It is aimed to determine the most important criteria in the supplier selection for each supply channel examined. Within the scope of the study, the wholesale markets brokers in the province of Denizli, domestic and national markets operating in the province and consumers living in different regions in the province are evaluated on quality, price, delivery, service, main product criteria and sub -expansions of these main criteria. AHP and TOPSIS methods were used to find important criteria in the election decisions of the suppliers at different levels, to select the most appropriate supplier and to compare the results. When the results obtained are examined, it is seen that the perspectives of the decision-makers other than consumers in the fresh fruit and vegetable supply chain are far from consumer expectations. [ABSTRACT FROM AUTHOR]

The cable industry carries out production with high raw material costs. Extruder lines make a difference in terms of product quality and costs. Therefore, the selection of the best line is important. In this study, four extruder lines were considered for a cable company for the production of a new insulation material. A total of seven evaluation criteria were determined for all alternatives. The decision-making group, consisting of production managers of the company, evaluated all alternatives under the criteria using linguistic expressions defined in Pythagorean fuzzy and triangular fuzzy number sets. As a result of the evaluations, objective criterion weights were determined using the Fuzzy CRITIC method with Pythagorean fuzzy numbers, and then the extruder line selection was carried out using the Fuzzy MAIRCA method with triangular fuzzy numbers. Sensitivity analyses were conducted to measure the impact of criteria on the obtained results. In the step of weighting the criteria, the energy usage criterion stood out. It was determined that the "Bobin" line is the most suitable for the conversion of the HFFR product into the final product. The study identified the priority line for the company where the application was carried out. [ABSTRACT FROM AUTHOR]

The construction of the railway, which is needed for the development of the Eastern Black Sea Region, is an issue that has been discussed and unresolved for about 110 years. The geomorphological structure of the region and the developments in the highway played a role in the delay of the railway construction. However, the developing technology in the railway, Turkey's being a part of the Iron Silk Road Project, and the agreements made with international connections have brought the railway construction to the region again. In the Environmental Plan (EP) approved and in force by the Ministry of Environment, Urbanization and Climate Change, four railway routes are planned to integrate the Eastern Black Sea region with the national/international railway network. These routes are; Samsun-Sarp, Trabzon-Erzincan, Of-Erzurum and Tirebolu-Bayburt. However, some of these routes are alternatives to each other and are not feasible and rational since the implementation of all planned routes requires great costs. The aim of this study is to develop a method for prioritizing and selecting the railway routes planned in the EP. Within the scope of this purpose, by using Analytical Hierarchy Process (AHP) and TOPSIS techniques, which are multi-criteria decision making methods, the routes were listed according to 4 criteria and 10 sub-criteria determined with the help of literature and expert team. As a result of the study; In both techniques, the order was the same and it was determined that the Samsun-Sarp railway was the most priority railway route. Trabzon-Erzincan came second, Of-Erzurum came third and Tirebolu-Bayburt came fourth. [ABSTRACT FROM AUTHOR]

Taşımacılıkta belirlenen bir güzergâh için en düşük maliyetle kaliteli hizmet verecek taşımacılık türünü seçmek çok önemlidir. Çünkü her bir taşımacılık türünün diğerine göre avantajları ve buna bağlı olarak ek maliyetleri mevcuttur. İşletmeler en uygun taşıma modunu seçerken birden çok kriteri ve alternatifleri birlikte değerlendirmek durumundadırlar. Bu değerlendirme birçok değişkenin aynı anda analiz edilmesini gerektiren karmaşık bir süreçten oluşmaktadır. Bu karmaşıklığın çözüm yollarında çok kriterli karar verme teknikleri kullanılabilmektedir. Bu çalışmada, Kayseri ilinde kiraz üretimi üzerinde faaliyet gösteren ve ihracat yapan bir lojistik firmasının taşıma modu seçim problemi ele alınmıştır. Taşıma modu seçim problemi için literatürün taranmasıyla elde edilen ve alanında uzman kişiler olan karar vericiler ile görüşmeler sonucu on üç kriter ve dört alternatif belirlenmiştir. Problemin çözümü için literatürde bu problemin çözümünde henüz kullanılmamış olan En İyi-En Kötü yöntemiyle kriterlerin önem ağırlıkları ve WASPAS (Weighted Aggregated Sum Product Assessment) yöntemiyle de seçenekler değerlendirilerek en uygun alternatifin seçimi gerçekleştirilmiştir.

Temiz bir enerji kaynağı olan ve doğal dengeyi bozmayan rüzgâr enerjisi, günümüzün en önemli yenilenebilir enerji kaynaklarından birisidir. Bu çalışmada rüzgâr çiftlikleri için uygun yer tespitinde kullanılan faktörler, oldukça yeni bir sübjektif ağırlıklandırma yöntemi olan FUCOM (Full Consistency Method-Tam Tutarlılık Yöntemi) yöntemi kullanılarak analiz edilmiştir. FUCOM, doğrusal programlama temelli bir yöntemdir ve diğer ağırlıklandırma yöntemlerinden daha az ikili karşılaştırmaya ihtiyaç duyar. Çalışmadaki değerlendirme modeli, üç temel boyutu ve on iki faktörü dikkate almaktadır. Bulgular, bir rüzgâr çiftliği sahasının tercih edilmesinin büyük ölçüde rüzgâr potansiyeline ve yerleşim yerlerine olan uzaklığına bağlı olduğunu göstermiştir. Ayrıca önerilen yöntemin tutarlılığını ve kullanışlılığını göstermek için bir duyarlılık analizi yapılmıştır. Bu çalışmanın sonuçları rüzgâr enerjisine yönelik politika belirlemekte kullanılabilir.

It is very important to choose the mode of transportation that will provide quality service at the lowest cost for a route determined in transportation. Because, each transportation mode has advantages over another and additional costs, accordingly. Businesses have to evaluate multiple criteria and alternatives together when selecting the most appropriate transport mode. This assessment consists of a complex process that requires many variables to be analyzed at the same time. Multi-criteria decision making techniques can be used in solving this complexity. In this study, the transportation mode selection problem of a logistics company operating on cherry production and exporting in Kayseri province is discussed. Through a literature review and interview with the decision makers, who are experts in their field, thirteen criteria and four alternatives have identified for the transport mode selection problem. In order to solve the problem, importance weight of the criteria is determined with the Best-Worst Method and then supplier alternatives are ranked using the WASPAS (Weighted Aggregated Sum Product Assessment) method. [ABSTRACT FROM AUTHOR]

Wind energy, which is a clean energy source and does not disrupt the natural balance, is today's one of the most popular renewable energy sources. In this paper, the factors which are utilized to determine a suitable site for wind farms have been analyzed by using the FUCOM (Full Consistency Method) method which is a relatively new subjective weighting method. FUCOM is a linear programming-based method and needs less pairwise comparisons than other weighting methods. The evaluation model in the study takes three main dimensions and twelve factors into consideration. The findings showed that the preference of a wind farm site depends largely on the wind potential and distance from residential areas. Furthermore, a sensitivity analysis was performed to demonstrate the consistency and usefulness of the suggested method. The results of this study could be used to determine the wind energy policy. [ABSTRACT FROM AUTHOR]

Tedarikçi değerlendirme ve seçimi, nitel ve nicel çok sayıda faktörün değerlendirilmesini gerektiren karmaşık birçok kriterli karar verme problemi olarak görülmektedir. Gerçek hayatta, belirsizlikler ve muğlaklık bir karar verme sürecinin ayrılmaz bir parçası olarak karşımıza çıkmaktadır. Bulanık küme teorisi, belirsizlik durumunda karar vermemize imkân sağlayan metotlardan bir tanesidir. Bu çalışmada, ikizkenar yamuk tip 2 bulanık TOPSIS yöntemi kısaca tanıtılmıştır. Tanıtılan yöntem, Türkiye’de bir tekstil firmasının tedarikçi seçimi problemine uygulanmıştır. Ayrıca, tip 2 bulanık TOPSIS yönteminin sonuçlarını desteklemek için aynı problem tip 1 bulanık TOPSIS ile de çözülmüştür. Duyarlılık analizi yapılarak önerilen çözümler farklı senaryolar altında incelenmiştir. Duyarlılık analizi sonuçlarına göre tip 2 bulanık TOPSIS daha efektif ve uygun çözümler üretmektedir.

In the world and in our country, most of urban transportation is performed by public transportation. Public transportation is a system which provides transportation easiness and opportunity to people, not to vehicles. Therefore, giving priority to public transportation system is necessary in organizing urban transportation. In this study, in order to reduce traffic intensity and to facilitate passenger transportation in Izmit urban transportation, It is tried to determine appropriate public transportation system. For this, firstly, alternatives which could be used for public transportation were determined. These alternatives are metro, metrobus, tram, light rail system and monorail. Afterwards, the variables affecting decision making about public transportation were determined. These variables are cost, transportation line features, vehicle characteristics, sensitivity to environment and customer satisfaction. Lastly, most appropriate public transportation system is proposed by using the axiomatic design method. As a result, light trail system and metrobus are determined as the most appropriate alternatives for Izmit public transportation system.Keywords: Urban transportation, Multi criteria decision making, Axiomatic design

Dünyada ve ülkemizde kent içi ulaşımın büyük bir bölümü toplu taşımacılıkla gerçekleştirilmektedir. Toplu taşıma, araçlara değil, insanlara ulaşım kolaylığı ve olanağı sağlayan bir sistemdir. Bu nedenle kent içi ulaşımın düzenlenmesinde toplu taşıma sistemlerine öncelik vermek gerekmektedir. Bu çalışmada İzmit kent içi ulaşımda trafik yoğunluğunun azaltılmasına ve yolcu taşımacılığının kolaylaştırılmasına yönelik olarak hangi toplu taşıma aracının daha uygun olduğu belirlenmeye çalışılmıştır. Bunun için öncelikle toplu taşıma için kullanılabilecek alternatifler belirlenmiştir. Bu alternatifler, metro, metrobüs, tramway, hafif raylı sistemler ve monoraydır. Devamında toplu taşıma konusunda karar vermeyi etkileyen değişkenler belirlenmiştir. Bu değişkenler; maliyet, ulaşım hattı özellikleri, araç özellikleri, çevreye duyarlılık ve müşteri memnuniyetidir. Son olarak aksiyomlarla tasarım yöntemi kullanılarak, en uygun toplu taşıma sistemi konusunda öneride bulunulmuştur. Yöntemin uygulanması sonucunda Hafif Raylı Sistemler ve Metrobüs, İzmit Toplu Taşıma sistemi yapısı için en uygun alternatifler olarak belirlenmiştir.Anahtar Kelimeler: Kent içi ulaşım, Çok kriterli karar verme, Aksiyomlarla tasarım

İşletmeler, olağanüstü rekabetin yaşandığı günümüz piyasa şartlarında, maliyetleri minimize, kârı maksimize edecek etkin stok politikalarını geliştirmek ve uygulamak zorundadır. Stoklar, üretim işletmelerinin toplam varlıklarının içinde önemli bir yere sahiptir. Bu önemli kalem için etkin stok kontrol ve yönetim politikalarının uygulanması, işletmenin geleceği için büyük önem taşımaktadır. Bu çalışma kapsamında, büyük bir holdingin kimyasallar grubunda faaliyet gösteren bir işletmesinde öncelikle stok kontrol yöntemlerinden ABC analizi uygulanmıştır. İkinci olarak stokların çok kriterli olarak sınıflandırılması için öncelikle Bulanık Analitik Hiyerarşi Prosesi (BAHP) yöntemi ile kriter ağırlıkları belirlenmiş ve İdeal Çözüme Yakınlığa Göre Tercih Sıralama Tekniği (TOPSIS) yöntemi kullanılarak stok kalemleri önem derecelerine göre sıralanmıştır. Çalışmanın sonunda stokların sınıflandırılmasında klasik ABC analizi ve BAHP-TOPSIS yöntemlerinin sonuçları arasındaki farklılıklar ortaya konmuştur.

Supplier evaluation and selection includes both qualitative and quantitative criteria and it is considered as a complex Multi Criteria Decision Making (MCDM) problem. Uncertainty and impreciseness of data is an integral part of decision making process for a real life application. The fuzzy set theory allows making decisions under uncertain environment. In this paper, a trapezoidal type 2 fuzzy multicriteria decision making methods based on TOPSIS is proposed to select convenient supplier under vague information. The proposed method is applied to the supplier selection process of a textile firm in Turkey. In addition, the same problem is solved with type 1 fuzzy TOPSIS to confirm the findings of type 2 fuzzy TOPSIS. A sensitivity analysis is conducted to observe how the decision changes under different scenarios. Results show that the presented type 2 fuzzy TOPSIS method is more appropriate and effective to handle the supplier selection in uncertain environment. [ABSTRACT FROM AUTHOR]

In the world and in our country, most of urban transportation is performed by public transportation. Public transportation is a system which provides transportation easiness and opportunity to people, not to vehicles. Therefore, giving priority to public transportation system is necessary in organizing urban transportation. In this study, in order to reduce traffic intensity and to facilitate passenger transportation in Izmit urban transportation, It is tried to determine appropriate public transportation system. For this, firstly, alternatives which could be used for public transportation were determined. These alternatives are metro, metrobus, tram, light rail system and monorail. Afterwards, the variables affecting decision making about public transportation were determined. These variables are cost, transportation line features, vehicle characteristics, sensitivity to environment and customer satisfaction. Lastly, most appropriate public transportation system is proposed by using the axiomatic design method. As a result, light trail system and metrobus are determined as the most appropriate alternatives for Izmit public transportation system. [ABSTRACT FROM AUTHOR]

In today's competitive market conditions, organizations have to develop and implement effective inventory policies to minimize their costs, and maximize profit. Inventories have an important place in the total assets of production enterprises. Applying efficient inventory control and management policies for this significant item is very important for the future of the organizations. In this paper, initially an ABC analysis method had been applied to a firm operating at the chemical group of a conglomerate. Then, to classify the inventory as multi criteria; primarily criteria weights are determined by the fuzzy analytic hierarchy process (FAHP) and then stock keeping units are ranked according to their significances with Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) method. Finally, the differences are presented between classical ABC analysis and FAHP-TOPSIS results for classifying the inventories. [ABSTRACT FROM AUTHOR]