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Like the other industries, information technologies are very important tools for the hotels’ success in the tourism industry. Various processes required for the hotel business can be integrated by using a proper system, and simultaneous data transfer among different channels can be facilitated. Due to its contribution in creating value for the customers and the increasing efficiency of the processes, substantial investments in information technologies are planned by the hotel management. Like most operation management problems, evaluation and selection of proper hotel information systems require considering multiple criteria. Also, considering the uncertainty inherent to the problem and difficulties during the evaluation process, an integrated IVIF-DEMATEL and IVIF-TOPSIS approach is utilized in this paper. The IVIF-DEMATEL is used for the criteria evaluation, and the weight determination phase and IVIF-TOPSIS is used to evaluate hotel information systems alternatives. An application for the Turkish tourism sector’s case is realized, and the results of the methodology are compared with the IVIF-VIKOR approach.

Logistics Centers (LCs) are among the most important facilities for rapid, cost effective, environmental friendly and secure logistics services to the urban logistics problems. Finding proper locations to LCs has an important effect on their success. In this study, LCs’ location selection problem for Istanbul Metropolitan area is investigated. Istanbul is a leading city of Turkey in many categories including various industries, import/export amounts, transportation infrastructure and population density. However, industrialization and urbanization have introduced numerous problems to Istanbul. New projects are continuously being announced for the problems of metropolis, however, they may also bring new problems if they are not punctiliously planned and applied. Hence, in this study, it is aimed to propose a systematic Multi-Criteria Decision-Making (MCDM) approach for the LCs’ location selection problem of Istanbul. In this approach, an integrated DEcision-MAking Trial and Evaluation Laboratory (DEMATEL) and Intuitionistic Fuzzy (IF) Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) method is utilized. DEMATEL is used to analyse the decision criteria and IF-TOPSIS is used to evaluate candidate locations for LCs. Considering the vagueness inherent to this decision-making problem, IF sets are used for the evaluation process. Results are compared with the results of IF-VIKOR (VIše Kriterijumska Optimizacija kompromisno Rešenje– multi-criteria optimization and compromise solution) technique. First publihed online 19 March 2020

The prevalence of environmental studies in the academy has increased in recent years, depending on the adverse effects of global warming on natural resources. Besides various environmentally benign applications, one of the most important instruments on eliminating the negative environmental effects of an increasing population is electric vehicles. There are various topics within the concept of electric vehicles, including the determination of electric vehicle type, routing, network design, and so on. However, in this study, determining the locations of electric charging stations is the main focus. The problem is handled as a multi-criteria decision-making problem with the consideration of the uncertainties in the decision-making environment. Specifically, the judgments of decision-makers play a critical role in the success of decisions, but for a decision-maker, it is usually difficult to express his/her preferences by using only one linguistic term due to the structure of some criteria type. Hence, with the proposed methodology, in this study, criteria are firstly classified as fuzzy and crisp according to their objective or subjective characteristics. Afterwards, besides the utilization of classic techniques for crisp type criteria, probabilistic linguistic terms sets are utilized for fuzzy type criteria with an extended version of TOPSIS. The proposed methodology is used for the comparison of 39 alternative electric charging locations in Istanbul, which is one of the most crowded cities in Europe.

Efficient planning and management of the workforce resources is one of the most essential requirements for the companies operating in the service sector. For banks, a large number of transactions coming to Central Operations Department from the branches or directly from the customers and their aim is to provide the best operational service with the highest efficiency with the limited workforce resources in the departments. In this study, a real assignment problem was discussed and the problem was considered as Generalized Assignment Problem. For the solution of the problem, related algorithms were listed and examined in the literature survey section. Then, a two-step method is proposed. First step prioritizes the task coming to the system by considering the customer types, service level agreement (SLA) times, cut-off times, task type. In the second step, a multi-objective mathematical model was developed to assign task to employee groups. A preference based optimization method called Linear Physical Programming (LPP) is used to solve the model. Afterward, proposed model was tested on real banking data. For all the tests, GAMS was used as a solver. Results show that proposed model gave better results compared with current situation. With the proposed solution method, the workloads of the profile groups working above their capacity were transferred to other profile groups with idle capacity. Thus, the capacity utilization rates of the profile groups were more balanced and the minimum capacity utilization rate was calculated as 41%.

The number of software projects has increased in recent years due to technological advancements. In addition to the other factors such as the qualifications of the staff, budget, leadership, the success of the projects also highly depends on how they are managed. There are various software project management models such as Waterfall, Prototype, Spiral, Incremental, Iterative and Agile, which have been applied in different types of software projects. Each has advantages and disadvantages over the other. Hence, any of them does not have absolute superiority over the others. Therefore, it is important to determine the most suitable one. In addition, depending on the sector, the conditions change and a solution methodology for the new problem environment is required. One of the biggest sectors, the banking sector, is specifically considered in this study. Conforming to the multi-criteria structure of the selection problem, Interval-Valued Neutrosophic Analytic Hierarchy Process (IVN-AHP) which is capable of providing solutions in fuzzy multi-criteria decision making environment is utilized in this study with the pairwise comparisons provided by the experts in the sector. Finally, the alternative software project management models are ranked, and the best one is obtained.

Customer satisfaction is an important factor for the success of the companies. Efforts for cost reduction and production productivity arenot enough for companies unless customer satisfaction is provided. For this reason, the aim of companies from all sizes is to provide thebest and fastest service to customers. Therefore, the establishment and operation of a logistics network is important for a company fromthe original point to the point of arrival of a product or service. In cargo companies, transportation is the main procedure in terms of timeand capacity constraints such as the number of vehicles, products and employees. With this aim, Vehicle Routing Problem with Backauls(VRPB) is investigated to reduce the total distance travelled by vehicles for a hypothetical postal service firm. It is assumed that there aremore than a hundred centers of the firm that send their vehicles to the reception centers after the distribution centers are visited. The P-Medianclustering model is used based on the distances of the centers to each other, since the exact algorithms cannot solve this problem dueto a great number of centers. Then, vehicles in each cluster routed by using a modified mathematical model. Günümüzde firmalar arası rekabetin kilit taşını müşteri memnuniyeti oluşturmaktadır. Daha az maliyet, daha çok üretim gibi hedefler müşteri memnuniyetini sağlanmadıkça firmalar için yeterli olmaz. Bu nedenle küçükten büyüğe bütün firmaların amacı müşteriye en iyi, en hızlı şekilde hizmet sunmak ve müşteri memnuniyeti sağlamaktır. Bir ürün veya hizmetin başlangıç noktasından varış noktasına kadar olan süreçte lojistik ağının çok iyi kurulması ve sürecin işlemesi bir firma için önemlidir. Özellikle temel görevi taşımacılık olan kargo firmalarının araç, ürün ve çalışan sayısı gibi kısıtlar ve zaman açısından çok iyi bir sürece sahip olması gerekmektedir. Bu amaçla, bu çalışmada posta hizmetleri için Araç Rotalama Problemi (ARP) üzerine çalışılmıştır. Araçlarını rotalarken önce dağıtım merkezlerine sonrasında kabul merkezlerine gönderen posta hizmetlerinin çok fazla şubesi bulunabilmektedir. Merkez sayısı çoğaldıkça en iyi çözümü veren algoritmalar bu problemi çözemeyeceği için merkezlerin birbirine olan uzaklıkları temel alınarak kümeleme metodu kullanılmıştır. Böylece birbirine yakın olan merkezler kendi içlerinde planlanarak toplam kat edilen uzaklık azaltılmaya çalışılmıştır.

Depending on the significant increase in the consumption and as a result in the production has caused some problems besides its utilities. One of the biggest concerns at this point is the adverse environmental effects of this growth. Hence, most of the companies take into account the environmental considerations during the design and implementation of their business facilities within their supply chains. As a result of these developments, the attempt to design supply chains greener has increased both practically and theoretically. Various studies have been performed dealing with green supply chains. However, in this study, it is focused on the greenness assessment of supply chains under four stages including inbound logistics, in-plant logistics, outbound logistics and reverse logistics. Different from the few studies in the literature, intuitionistic fuzzy (IF) approach which enables to handle fuzziness and hesitancy is used within DEMATEL and ANP techniques to measure supply chain greenness. The related steps are explicitly provided within the proposed methodology. In general, firstly the main dimensions of greenness are determined with the related indicators. Then, regarding the dependency between the dimensions, the relation network is obtained via IF-DEMATEL by taking the evaluations of supply chain experts. Afterwards, based on the network diagram and expert judgments, the importance weights of dimensions are provided with IF-ANP and used in the developed greenness scoring system. An application in a firm’s supply chain is performed to demonstrate the validation of the proposed methodology and consequently, the greenness score is obtained.

Maintenance routing is one of the most complicated problems of operations research applications for airline industry. In this study, airline industry operations' main applications and subjects are basically mentioned and literature is briefly reviewed. This study is conducted under the headings of; Fleet Assignment, Aircraft Routing, Maintenance Routing and Crew Scheduling. Additionally, network models are explained basically on an example flight program. This study's purpose is to be a guide for the new researchers of this area through operations research applications for airline industry and to introduce maintenance routing problem literature.

Transportation costs have an important effect on companies’ competition capability in various sectors. To realize a positive effect, transportation industry should provide some specific performance criteria related with the economical efficiency and service quality. Also an increase in this performance degree depends on the obtaining optimum results of using the logistical resources in a convenient manner by the specialized logistics service providers. In this study, considering the effects of transportation modes on constituting a methodology that is interested in a strategic subject like constructing a transportation network is emphasized. In the process of selecting the most convenient transportation modes, all the required criteria are determined considering the related literature and the opinions of the experts. Then the analytical network process methodology is used to solve this selection problem. The close relationship between the transportation modes that will be used among the points in the network and the points that will be used for short storages and transshipment activities is considered. And the analytical network process is again used to select the most convenient ones among the alternative port locations. After decision making on these two important points, optimizing the freight flow among the supply chain by choosing the right transportation modes at each stage is aimed. To realize that optimization, the aims of decision makers from different levels or from different functional areas are satisfied by using the multilevel programming technique. Finally, the proposed methodology is applied on a transportation project of a logistic service provider, which gives service in a multimodal, multicommodity, multilevel and multiechelon transportation network.

In this study, a multi-objective model for the reverse logistics network design (RLND) problem and a novel methodology are proposed. The proposed methodology is comprised of two stages: the centralised return centre (CRC) evaluation stage and the reverse logistics network design (RLND) stage. In the first stage an integrated ANP and fuzzy-TOPSIS methodology is utilised. In the second stage, using the CRC weights obtained in the first stage, the RLND model is solved via genetic algorithms (GAs). The proposed methodology is applied to a case from the Turkish white goods industry. The results are discussed and analysed.

Material handling system selection process has an important effect on productivity of manufacturing systems. Considering the importance of this process, it can be seen that there is a necessity to establish a systematic approach. In this study, to determine the best material handling system alternative, PROMETHEE approach is utilized. With the aim of taking into account the vagueness in the evaluation process and obtaining decision maker evaluations in an easier way with linguistic terms, fuzzy sets are utilized. To this end, a modified version of PROMETHEE is used. To foster the better understanding of the methodology, a real life application of a manufacturer is realized.

Material handling equipment selection problem (MHESP) is an important decision making area for the companies, since it has a direct effect on manufacturing and service productivity. In this study, an integrated fuzzy multi-criteria decision making methodology for MHESP is proposed. The proposed approach is utilized from fuzzy sets, Analytic Network Process (ANP) and Preference Ranking Organization METHod for Enrichment Evaluations (PROMETHEE) approaches. Evaluation criteria for the MHESP is weighted by fuzzy-ANP (F-ANP) approach, then, alternative material handling equipments are evaluated by fuzzy-PROMETHEE (F-PROMETHEE) approach. The methodology is applied for a manufacturing company to prove its effectiveness. Finally, some sensitivity analyses are conducted to show the results' sensitiveness to the changes of the weights of the evaluation criteria.

International audience; The fundamental objective of supply chain management (SCM) is to integrate various suppliers to satisfy market demand. Supplier evaluation and selection is very important for establishing an effective supply chain. As a matter of fact, supplier selection consists of both qualitative and quantitative criteria, so it is considered as a multi criteria decision making (MCDM) problem. Under incomplete or uncertain information, the fuzzy set theory allows us make decisions with approximate reasoning. In order to overcome the uncertainty which is constituted by vague situations in supplier selection, we utilize the “extension of the PROMETHEE method in a fuzzy environment” (F-PROMETHEE). In this chapter, multi criteria supplier selection based on a fuzzy PROMETHEE method with an application to supplier selection decision problem is conducted. The main advantages of the methodology are the user friendliness coming from the linguistic evaluations, and the consideration of the vagueness or fuzziness inherent to the decision making environment. Hence, the method can be an efficient and effective methodology to be used by decision makers on supply chains. The proposed methodology can also be applied to any other selection problem.

The concept of a supply chain exists for over twenty years but partners and configuration selection process still is rather unstructured. In order to increase value in any supply chain, a more comprehensive and integrative approach is required to select the right partners and establish the right configuration along the chain. Under economic growth wrong decisions does not jeopardize profitability dramatically. However, recent economy downtrends, has made the choice of suitable partners in the dynamic supply chain a key strategic concern. The nature of these decisions usually is complex and unstructured. This paper aims to present an intuitionistic fuzzy Chouquet integral operator based approach to partners and configuration selection. In order to bring structure in the evaluation process, the supply chain operations reference (SCOR) model developed by Supply Research Council is employed. The paper discusses the development of the value chain concept from partners selection perspective, outlines general similarities and differences of the value chain and the SCOR, and uses a simple V-form supply chain example to establish the proposed approach. Finally, results of the application and sensitivity of the results to the change in the selection criteria weights are discussed.

Locating an undesirable facility is a sophisticated problem, for the evaluation procedures involve several objectives and the solution to the problem calls for some compromises to be made between probable conflicting criteria. This paper addresses the problem of undesirable facility location selection using the analytic network process (ANP), a multi-criteria decision-making technique. The ANP technique enables us to consider both qualitative and quantitative criteria as well as the interdependencies and feedbacks. A number of criteria (benefits, opportunities, costs and risks) and their sub-criteria are considered for siting a new facility with which this study has dealt. The questions of what criteria would be considered and what the interdependencies between these criteria and their weights would be were discussed and determined via interviews with some competent authorities of the Istanbul Municipality and of two environmental organizations. Four representative locations were evaluated and the most convenient one was selected. This was followed by the sensitivity analyses of the results.