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1

Relationship marketing orientation in healthcare organisations with the AHP method. Internal and external customer perspective

Ersoy Yusuf, Tehci Ali

Operations Research and Decisions

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2023

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Vol. 33, No. 1

35--45

EN

Adopting the relationship marketing approach in health institutions and evaluating the weights of its dimensions will benefit the effectiveness of marketing strategies. This study aimed to determine the critical levels of relationship marketing orientation components in private health institutions using the analytical hierarchy process (AHP). In the study, relationship marketing orientation was evaluated according to six criteria in line with the opinions of five experts for employees and 20 people who previously benefited from health services for their customers. As a result, the criterion with the highest priority value was communication with 0.259, and the best health company A. Furthermore, the AHP method results were compared with TOPSIS, EDAS, and CODAS methods. In addition, the Spearman Correlation method was used to determine the correlation between the results.

2

European integration and development of the EU-10 countries in view of selected social phenomena

Smolińska Kinga, Józefowicz Karolina, Bednárová Lucia

Zeszyty Naukowe. Organizacja i Zarządzanie / Politechnika Śląska

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2022

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z. 157

509--522

EN

Purpose: The aim of this paper is to determine the level of development in the EU-10 countrie in view of social phenomena. Design/methodology/approach: the TOPSIS method was applied to rank countries in terms of social phenomena – the list comprised countries, which in 2004 accessed the EU. The paper focused on social phenomena, i.e. health, the labour market, housing, demography and education. Findings: It refers to the basic assumptions and the importance of integration in the international context as well as the related theories. Moreover, it presents the relationship between integration and the level of development in countries in terms of the social aspects. At the same time it discusses the process of social changes which have taken place in the Central and Eastern European countries (CEESs) since their accession to the European Union. Research limitations/implications: The text discusses problems related to the European integration and social development in the EU countries. Practical implications: The manuscript concerns social development in the EU-10 countries and European integration. It may be of interest for the broadly understood governmental sector. Social consequences: Conducted studies will constitute the basis for the development of European and national development strategies in terms of improvement of welfare for the populations, while also indicating the direction of changes and ensuring comparability of the results concerning transformations in the countries, which accessed the EU in 2004. Originality/value: The originality of the study will stem from the application of the TOPSIS method, required to classify the countries and to determine the standard of their development in terms of social phenomena.

3

Conceptual approach to valuation of climate change in EU countries through the prism of economic activities

Stankevičienė Jelena, Borisova Jelena

Rynek Energii

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2022

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Nr 5

80--88

EN

In our days' countries pursue not just to have higher or maintain economic growth, but society faces another challenge – to combat climate change: to slower increase of global temperature by decreasing amount of green gas emission. Globalization processes have increased green gas emission. The problem of climate change becomes an overall problem of all countries, as green gas emissions produced by any country has an overall impact on environment of the earth. Public administration and public policies face the problem how to combat climate change not constraining the economy too much. The purpose of the paper is to evaluate the extent to which EU countries are affected to climate change according economic and social factors of countries that can be seen as drivers of green gas emissions. The study relates green gas emission intensity to the extent to which the country is possible to be exploded to climate change according to its data on industry, energy, waste, and agriculture of EU countries. TOPSIS method is used to rank EU countries in combating climate change. The conceptual approach to ranking climate change through the prism of countries economic activities is developed. There are some research limitations – statistical data on the industry, energy, waste, agriculture is limited in order to fulfil the tasks of the research.

4

Effect of novel grain refiner and Ni alloying additions on microstructure and mechanical properties of Al-Si9.8-Cu3.4 HPDC castings – optimization using Multi Criteria Decision making approach

Apparao K. Ch., Bannaravuri Praveen Kumar, Pulisheru Kumar Swamy, Francis E. D., Sunny Kalakanda Alfred, Babu Rao Gadudasu, Daniel P. Freedon, Kumar Birru Anil

Materials Science Poland

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2022

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Vol. 40, No. 1

9--24

EN

Studies dealing with process improvement of aluminum alloys and their grain structure refinement are the current area of interest in casting companies and foundries, the aim being to enhance the properties of the base metal. In this study, the microstructural and mechanical properties of commercial Al-Si9.8-Cu3.4 alloy die castings influenced by different additions of Al-3.5FeNb-1.5C master alloy (viz. 0 wt.%, 0.1 wt.%, and 1.0 wt.%) as a new grain refiner and Al-6Ni master alloy (viz. 0 wt.%, 0.5 wt.%, and 5.0 wt.%) as an alloying element have been investigated. A multi-criteria decision-making approach for the improvement of the die casting process was performed using grey relational analysis (GRA) and TOPSIS analytical techniques. It was observed that the primary aluminum α-grains were significantly refined, particularly at the lower addition level 0.1 wt.% of Al-3.5FeNb-1.5C, and conversely, poor grain refining efficiency was observed at a higher addition level 1.0 wt.% of Al-3.5FeNb-1.5C. Due to the refinement by Al-3.5FeNb-1.5C grain refiner and the effect of Ni alloying element additions, the ultimate tensile strength (UTS) and hardness (Brinell and micro) of the Al-Si9.8-Cu3.4alloy are improved, particularly at 0.1 wt.% of Al-3.5FeNb-1.5C and 0.5 wt.% of Al-6Ni master alloys. Quantitatively, UTS, Brinell hardness, and microhardness values have been increased by 12.3%, 7.0%, and 20%, respectively.

5

Multi-objective decision making for Z Coordinator and overcut in μ - EDM process using tungsten carbide electrode for machining of titanium alloy

Nguyen Phan-Huu

Journal of Machine Engineering

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2022

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Vol. 22, No. 1

138--149

EN

Research on optimization of technological parameters in micro-EDM is very important, and especially results in multi-objective optimization problem. It led to improve machining performance like machining accuracy, reduced electrode wear and improved surface quality. Recent studies mainly refer to the quality indicators of machining productivity and electrode wear, besides that machining accuracy and surface quality are also very important indicators but published results about them is very limited. In this study, Z Co-Ordinate (Z) and overcut (OC) in micro-EDM using tungsten carbide (WC) electrode for Ti-6Al-4V were decided simultaneously by TOPSIS. Technological parameters which include Voltage (V), Capacitance (C) and Response surface methodology (RSM) were investigated in the presented research work. The results showed that the quality parameters Z and OC at optimal conditions were significantly improved. The surface quality behind the micro-EDM is also analyzed and evaluated, and it is good.

6

Performance Evaluation of Hydro Power Projects in India Using Multi Criteria Decision Making Methods

Manoj Vasupalli, Rathnala Prasanthi, Sura Srinivasa Rao, Sai Sake Namruth, Murthy Metta Venkata Ramana

Ecological Engineering & Environmental Technology

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2022

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Vol. 23, iss. 5

205--217

EN

In the contemporary period of the green economy, energy planning has grown more complicated due to the inclusion of numerous standards, including technical, social, economic, and environmental. This, in turn, restricts the ability of decision-makers to make the most efficient use of energy resources. In addition, the difficulty of energy planning is exacerbated by topographical restrictions on renewable energy systems, the majority of which are found in nature. Based on factors such as total installed capacity, total reservoir capacity, total surface capacity, the height, length, number of units, and the cost of the dam were used to determine the finest hydro power project in India, according to this study. For performance evaluation, multi criteria decision making (MCDM) techniques like analytic hierarchy process (AHP) and TOPSIS (technique for order reference by similarity to ideal solution) are used in conjunction with VIKOR (vlekriterijumsko kompromisno rangiranje) for performance evaluation. AHP is used to calculate the weights of each criteria. The TOPSIS and VIKOR methods will utilise these weights to choose the optimal option. For the purpose of demonstrating the approaches’ applicability, an in-depth case study of various hydropower facilities in India was carried out.

7

Modeling the designs in terms of logistics service center placement: a case study

Stopka Ondrej, Droździel Paweł, L'upták Vladimir

Archives of Transport

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2022

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Vol. 64, iss. 4

59--71

EN

Suggesting the proper location for logistics facility can be considered as a decision making problem, wherein the final solution/decision is affected by multiple external or even internal circumstances. In order to address the decision making issues, various multi-criteria decision making (MCDM) techniques may be implemented; and hence, they can be applied even when making a decision about an adequate logistics service center (LSC) placement in an examined territory (i.e., national logistics network of the selected territory), which is an aim of this manuscript. Following the statements above, as for the individual instruments of MCDM to be implemented in terms of the crucial objective of this research, the definite decision making process will be carried out by applying the Analytic Hierarchy Process (AHP) followed by the Technique for Order Preference by Similarity to the Ideal Solution (TOPSIS), on the basis of criteria weights defined by the Saaty pairwise comparison method. The methods used appear to be ideal instruments towards decision making on the most suit-able location which is represented by the region in our case. Subsequently, these will be ordered from the most preferred to least one by using a preference ranking. As a result of the application of AHP and TOPSIS approaches, based on the conducted calculations in regard to decision making on identifying the proper LSC location out of eight selected regions, one specific region will be defined as the most suitable (so-called compromise) scenario. Individual tools allow for reducing the number of assigned criteria that are taken into account in searching process for individual solutions. In order to objectify the entire decision making procedure, ten topic-involved experts having practical experience with a subject of logistics object allocation will be asked to participate in the process. Preferences differ from one decision maker (expert) to another; hence, the outcome depends on who is making decisions and what their goals and preferences are.

8

Decision-Making Process Development for Industry 4.0 Transformation

Sajjad Ahmad, Ahmad Wasim, Hussain Sulman

Advances in Science and Technology. Research Journal

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2022

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Vol. 16, no 3

1--11

EN

Development of design characteristics based dynamic decision support framework is presented in the current study, to facilitate the decision makers in the transformation of system in the industry 4.0 paradigm. The model development is designed for a robust decision-making approach to integrating human and machine knowledge to adopt smart technologies and system design. The system is based on prioritization of the industry 4.0 design principles and characteristics including flexibility, self-adaptability, self-reconfigurability, context awareness, decision autonomy, and real-time capabilities. It has been revealed from an industrial field study, the companies facing difficulty to transform the system, and systematics approach needed to overcome the challenge. A decision support process has been developed as an integrated approach to embedding human knowledge. The developed process has been validated using Technique for Order of Preference by Similarity to Ideal Solution, the results depict the operational flexibility, has been most crucial transformation characteristics prioritized using the Analytical Hierarchical Process. The developed process has the capability to help the system development and estimate the factors involved in the transformation.

9

Equipment selection for an e-commerce company using Entropy-based TOPSIS, EDAS and CODAS methods during the COVID-19

Ersoy Yusuf

LogForum

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2021

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Vol. 17, no. 3

341--358

EN

Background: The importance and market share of e-commerce has been increasing with the COVID-19 pandemic in recent days. Employees sometimes cannot go to the workplace due to epidemics such as COVID-19 that is spreading rapidly around the world, natural disasters and accidents. Companies can continue to serve their customers with the internet infrastructure and computer technologies they will provide to their employees. Thus, e-commerce companies can provide a sustainable competitive advantage in the sector. Working with the right suppliers is one of the important decisions that will improve the service quality of the firms and affect the sustainability of the enterprise. Methods: This study aims to select the best laptop for a company in the online trade industry using Entropy-based EDAS, CODAS and TOPSIS methods. In the study, 6 alternative laptops have been evaluated according to hard disk capacity, ram, battery power, processor speed, weight, price criteria. The Entropy method has been used to identify the weights of the criteria in the study. These criteria weights have been used in EDAS, CODAS and TOPSIS methods. TOPSIS, EDAS and CODAS methods have been used to determine the best alternative. Also, the correlation between the results of the TOPSIS, EDAS and CODAS methods has been examined with the Spearman Correlation approach. Results: As a result of the Entropy method, it has been determined that the most important criterion is the hard disk capacity criterion. TOPSIS, EDAS and CODAS method results have been compared and the most suitable alternative has been selected. According to the results of the study, the best alternative has been selected as A5. Spearman Correlation analysis results show that there was a strong positive relationship between the methods used and the results obtained. Conclusions: The study differs from existing studies in the literature in that it is the first study in which laptop selection was made using TOPSIS, EDAS and CODAS methods together. The results of this study can be compared with the results of future studies that will be carried out using different MCDM methods and different data.

10

Selection mining methods via multiple criteria decision analysis using TOPSIS and modification of the UBC method

Ali Mahrous A.M., Kim Jong-Gwan

Journal of Sustainable Mining

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2021

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Vol. 20, iss. 2

49--55

EN

Mine designers often face difficulties in selecting an appropriate mining method; however, such a method should be selected based on ore and rock characteristics. The selection of mining methods can be considered a type of multi-criteria decision making, and this depends on many factors used in the selection process. The general method used in this field is the University of British Columbia (UBC) method, which determines the criteria of the properties that are compared to determine the best and worst of several mining methods. In this paper we used as new technique which defines as Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS). The criteria considered in the UBC method include general shape, ore thickness, ore plunge, and grade distribution, beside the rock quality designation (RQD), and the rock substance strength (RSS). This paper presents an improved TOPSIS method based on experimental design. Additionally, this paper will introduce a modified version of the UBC method that can be employed based on Excel sheet. The best mining methods is cut and fill stoping and top slicing with the same rank equal 0.72, and the second-best mining method is square set stoping with rank equal 0.65.

11

Application of TOPSIS and PIV methods for multi-criteria decision making in hard turning process

Trung Do Duc

Journal of Machine Engineering

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2021

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Vol. 21, No. 4

57--71

EN

In this study, TOPSIS and PIV methods were applied for multi-criteria decision making in hard turning process. Experiments have been conducted in accordance with an experimental matrix designed by the Taguchi method with a total of twenty-seven experiments. At each experiment, the values of coolant concentration, nose radius, coolant flow, cutting velocity, feed rate and depth of cut have been changed. Surface roughness, flank wear and roundness error have been selected as output criteria. The weights of criteria have been determined by three methods, inclusive of Equal weight, ROC weight and Entropy weight. The combination of multi-criteria decision-making methods with three weighting methods gives six ranking options of the experiments. The purpose of ranking the experiments is to find the experiment at which the three output parameters are ensured to have the minimum value simultaneously.

12

An approach to generalization of the intuitionistic fuzzy topsis method in the framework of evidence theory

Dymova Ludmila, Kaczmarek Krzysztof, Sevastjanov Pavel, Sułkowski Łukasz, Przybyszewski Krzysztof

Journal of Artificial Intelligence and Soft Computing Research

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2021

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Vol. 11, No. 2

157--175

EN

A generalization of technique for establishing order preference by similarity to the ideal solution (TOPSIS) in the intuitionistic fuzzy setting based on the redefinition of intuitionistic fuzzy sets theory (A−IFS) in the framework of Dempster-Shafer theory (DST) of evidence is proposed. The use of DST mathematical tools makes it possible to avoid a set of limitations and drawbacks revealed recently in the conventional Atanassov’s operational laws defined on intuitionistic fuzzy values, which may produce unacceptable results in the solution of multiple criteria decision-making problems. This boosts considerably the quality of aggregating operators used in the intuitionistic fuzzy TOPSIS method. It is pointed out that the conventional TOPSIS method may be naturally treated as a weighted sum of some modified local criteria. Because this aggregating approach does not always reflects well intentions of decision makers, two additional aggregating methods that cannot be defined in the framework of conventional A−IFS based on local criteria weights being intuitionistic fuzzy values, are introduced. Having in mind that different aggregating methods generally produce different alternative rankings to obtain the compromise ranking, the method for aggregating of aggregation modes has been applied. Some examples are used to illustrate the validity and features of the proposed approach.

13

Using TOPSIS and AHP Methods in Job Distribution to Subcontractors in Apparel Companies and Comparing the Results

Bulur Öykü Ceren, Kayar Mahmut

Fibres & Textiles in Eastern Europe

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2021

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Nr 4 (148)

24--31

EN

The ready-to-wear sector is one of the areas where outsourcing is used extensively due to reasons such as being a labour-intensive sector, having a wide range of products, and the time pressure caused by the very short shelf life of the product. Therefore, garment companies work with a large number of subcontractors, which raises the problem as to which subcontractor/subcontractors work will be distributed to as well as how much to each subcontractor. Using multi-criteria decision-making methods in solving this complex problem helps decision-makers make the right decisions. From this point of view, multi-criteria decision-making methods are very important decision-making tools in terms of the optimal distribution of work to subcontractors. Within the scope of the study, the TOPSIS and AHP methods were used to distribute orders to subcontractors and compared.

PL

Sektor odzieżowy jest jednym z obszarów, w których szeroko stosowany jest outsourcing, głównie z takich powodów, jak: pracochłonność sektora, szeroka gama produktów oraz presja czasowa spowodowana bardzo krótkim okresem trwałości produktu. Dlatego firmy odzieżowe współpracują z dużą liczbą podwykonawców, co rodzi problem, do jakiego podwykonawcy/podwykonawców zostanie przydzielona praca, a także do jakiej kwoty zostanie przydzielona każdemu z podwykonawców. W podejmowaniu właściwych decyzji w kwestii tego złożonego problemu pomaga decydentom możliwość korzystania z wielokryterialnych metod podejmowania decyzji. Z tego punktu widzenia wielokryterialne metody podejmowania decyzji są bardzo ważnymi narzędziami decyzyjnymi z punktu widzenia optymalnego podziału pracy na podwykonawców. W ramach badania wykorzystano metody TOPSIS i AHP do dystrybucji zamówień do podwykonawców i porównano je.

14

Towards cognitive decision support: A model of behavioural assessment of multi-criteria methods

Roszkowska Ewa, Wachowicz Tomasz

Control and Cybernetics

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2021

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Vol. 50, No. 1

145--168

EN

The Negotiation Support Systems often implement multiple criteria decision aiding (MCDA) techniques for building a negotiation scoring system. Those formal models should meet the needs, motivations, expectations, and cognitive abilities of users. In this paper, we try to explore the effects of decision maker’s subjective perception of ease of use, time requirements, interface, preference representation, and efficiency of a particular MCDA method on the choice regarding the future use of this method. The multinomial logistic regression model is built and analysed. The analysis is based on data from online decision making experiments, where three MCDA methods were implemented, i.e. AHP, SMART, and TOPSIS. The study provides several interesting findings, concerning the behavioural aspects of multiple criteria decision aiding in software support systems. Most of the users recommended TOPSIS as the best one for supporting decisions in the future. This is a fast technique, for which we used an attractive graphical interface, suggesting that these factors play a crucial role in the users’ choices. However, the causative regression model showed that the user’s positive experience in using a particular method, i.e. its effectiveness in solving an exemplary numerical case, has the highest impact on the method’s choice for future use. The second most important factor is the adequacy in representing the user’s preferences by this method. We show, however, that the strengths of effects and their significance may vary across the methods. Understanding the decision maker’s evaluations of the MCDA techniques may help build a cognitive negotiation support system that satisfies the user’s expectations.

15

Comparison of Electrochemical Micromachining Performance using TOPSIS, VIKOR and GRA for Magnetic field and UV rays heated Electrolyte

Saravanan K. G., Thanigaivelan R., Soundarrajan M.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2021

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Vol. 69, nr 5

art. no. e138816

EN

The application of micro components in various fields such as biomedical, medical, automobile, electronics, automobile and aviation significantly improved. To manufacture the micro components, different techniques exist in the non-traditional machining process. In those techniques, electrochemical micromachining (ECMM) exhibits a unique machining nature, such as no tool wear, non-contact machining process, residual stress, and heat-affected zone. Hence, in this study, micro holes were fabricated on the copper work material. The sodium nitrate (NaNO₃) electrolyte is considered for the experiments. During the experiments, magnetic fields strength along with UV rays are applied to the electrolyte. The L₁₈ orthogonal array (OA) experimental design is planned with electrolyte concentration (EC), machining voltage (MV), duty cycle (DC) and electrolyte temperature (ET). The optimization techniques such as similarity to ideal solution (TOPSIS), VlseKriterijumska Optimizacija I Kompromisno Resenje (VIKOR) and grey relational analysis (GRA) were employed to find the optimal parameter combinations. The entropy weight method is used to assess the weight of responses such as MR and OC. The optimal combination using TOPSIS, VIKOR and GRA methods shows the same results for the experimental runs 8, 9 and 7, and the best optimal parameter combination is 28 g/l EC, 11 V MV, 85 % DC and 37°C ET. Based on the analysis of variance (ANOVA) results, electrolyte concentration plays a significant role by contributing 86 % to machining performance. The second and least contributions are DC (3.86 %) and ET (1.74 %) respectively on the performance. Furthermore, scanning electron microscope (SEM) images analyses are carried out to understand the effect of magnetic field and heated electrolyte on the work material.

16

Towards Objectification of Multi-Criteria Assessments: a Comparative Study on MCDA Methods

Bączkiewicz Aleksandra, Wątróbski Jarosław, Kizielewicz Bartłomiej, Sałabun Wojciech

Annals of Computer Science and Information Systems

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2021

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Vol. 25

417--425

EN

Objective evaluation in problems considering many, often conflicting criteria is challenging for the decision-maker. This paper presents an approach based on MCDA methods to objectify evaluations in the camera selection problem. The proposed approach includes three MCDA methods, TOPSIS, VIKOR, COMET, and two criterion weighting techniques. Two ranking similarity coefficients were used to compare the resulting rankings of the alternatives: WS and rw. The performed research confirmed the importance of the appropriate selection of multi-criteria decision-making methods for the solved problem and the relevance of comparative analysis in method selection and construction of objective rankings of alternatives.

17

The performance assessment of reverse osmosis stations at Al-Mahalabea area

Ahmed Mohammed F.

Przegląd Naukowy Inżynieria i Kształtowanie Środowiska

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2020

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Vol. 29, No. 3

332--342

EN

The present study assesses RO stations at four sites in Al-Mahalabea area – Nineveh governorate, Iraq during the summer of 2013. The performance of RO stations are ranked by two methods: the Simple Additive Weight (SAW) and the Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS). Two groups of samples were collected from feed and permeate water for two periods (at zero time of operation and after ten weeks of operation) with eleven parameters for each sample were analysed. The highest overall rejection R efficiency appeared with the first set of parameters more than 90% (SO4, TDS, NO3, TH, and turbidity), while the second set was the least (Cl, Na, and total alkalinity – TA) ranged between 65 and 85%. It is observed that both the SAW and the TOPSIS methods are accurate to predict the performance efficiency.

18

A Holistic Approach to Polymeric Material Selection for Laser Beam Machining using Methods of DEA and TOPSIS

Roy Manish Kumar, Shivakoti Ishwer, Phipon Ruben, Sharma Ashis

Foundations of Computing and Decision Sciences

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2020

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Vol. 45, No. 4

339--357

EN

Laser Beam machining (LBM) nowadays finds a wide acceptance for cutting various materials and cutting of polymer sheets is no exception. Greater reliability of process coupled with superior quality of finished product makes LBM widely used for cutting polymeric materials. Earlier researchers investigated the carbon dioxide laser cutting to a few thermoplastic polymers in thickness varying from 2mm to 10mm. Here, an approach is being made for grading the suitability of polymeric materials and to answer the problem of selection for LBM cutting as per their weightages obtained by using multi-decision making (MCDM) approach. An attempt has also been made to validate the result thus obtained with the experimental results obtained by previous researchers. The analysis encompasses the use of non-parametric linear-programming method of data envelopment analysis (DEA) for process efficiency assessment combined with technique for order preference by similarity to an ideal solution (TOPSIS) for selection of polymer sheets, which is based on the closeness values. The results of this uniquely blended analysis reflect that for 3mm thick polymer sheet is polypropelene (PP) to be highly preferable over polyethylene (PE) and polycarbonate (PC). While it turns out to be that polycarbonate (PC) to be highly preferable to other two polymers for 5mm thick polymer sheets. Hence the present research analysis fits very good for the polymer sheets of 3mm thickness while it deviates a little bit for the 5mm sheets.

19

Warehouse location selection with TOPSIS group decision-making under different expert priority allocations

Ocampo Lanndon, Genimelo Gianne Jean, Lariosa Jerome, Guinitaran Raul, Borromeo Philip John, Aparente Maria Elena, Capin Teresita, Bongo Miriam

Engineering Management in Production and Services

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2020

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Vol. 12, no. 4

22--39

EN

Warehouses are crucial infrastructures in supply chains. As a strategic task that would potentially impact various long-term agenda, warehouse location selection becomes an important decision-making process. Due to quantitative and qualitative multiple criteria in selecting alternative warehouse locations, the task becomes a multiple criteria decision-making problem. Current literature offers several approaches to addressing the domain problem. However, the number of factors or criteria considered in the previous works is limited and does not reflect real-life decision-making. In addition, such a problem requires a group decision, with decision-makers having different motivations and value systems. Analysing the varying importance of experts comprising the group would provide insights into how these variations influence the final decision regarding the location. Thus, in this work, we adopted the Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) to address a warehouse location decision problem under a significant number of decision criteria in a group decision-making environment. To elucidate the proposed approach, a case study in a product distribution firm was carried out. Findings show that decision-makers in this industry emphasise criteria that maintain the distribution networks more efficiently at minimum cost. Results also reveal that varying priorities of the decision-makers have little impact on the group decision, which implies that their degree of knowledge and expertise is comparable to a certain extent. With the efficiency and tractability of the required computations, the TOPSIS method, as demonstrated in this work, provides a useful, practical tool for decision-makers with limited technical computational expertise in addressing the warehouse location problem.

20

An artificial neural network model supported with multi criteria decision making approaches for maintenance planning in hydroelectric power plants

Özcan Evrencan, Danışan Tuğba, Yumuşak Rabia, Eren Tamer

Eksploatacja i Niezawodność

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2020

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Vol. 22, no. 3

400--418

EN

Power 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.

PL

Elektrownie to zakłady produkcyjne o dużej skali, których głównym celem jest nieprzerwane, niezawodne, wydajne, rentowne oraz przyjazne dla środowiska wytwarzanie energii. Utrzymanie ruchu stanowi jeden z kluczowych czynników pozwalających na osiągnięcie tych szeroko zakrojonych celów, które określa się wspólnym mianem zrównoważonych dostaw energii. W elektrowniach, procesami utrzymania ruchu, realizowanymi w celu zapewnienia zrównoważonych dostaw energii, zarządza się z uwzględnieniem kosztów związanych z wymogami czasowymi, kosztów materiałów i robocizny oraz strat wytwarzania energii. Ponieważ elektrownie wykorzystują tysiące różnych urządzeń, niezwykle ważne jest prognozowanie dat wystąpienia uszkodzeń oraz zapewnienie bezawaryjnego utrzymania ruchu. W przedstawionych badaniach, rozważano problem planowania utrzymania ruchu sprzętu o wysokim poziomie krytyczności na przykładzie jednej z dużych elektrowni wodnych, która na koniec 2018 r. pokrywała jedną piątą zapotrzebowania Turcji na energię elektryczną. W pierwszym etapie badań, kryteria oceny określone przez ekspertów zatrudnionych w elektrowni ważono za pomocą powszechnie stosowanej w literaturze metody procesu hierarchii analitycznej (AHP) w celu ustalenia poziomów krytyczności poszczególnych elementów wyposażenia elektrowni. Aby opracować ostateczny ranking priorytetowości elementów wyposażenia elektrowni na podstawie określonych wcześniej wag, zastosowano technikę TOPSIS, która polega na porządkowaniu preferencji na podstawie podobieństwa do idealnego rozwiązania. Techniki tej użyto ze względu na jej zalety, których nie mają inne algorytmy oparte na relacji przewyższania (ang. outranking algorithms). Na podstawie wyników otrzymanych dla 14 głównych grup urządzeń o najwyższym poziomie krytyczności, określonym na podstawie danych pochodzących z elektrowni, oszacowano czasy pomiędzy dwiema awariami, a na ich podstawie zaplanowano działania konserwacyjne. W fazie szacowania, opracowano model sztucznej sieci neuronowej (ANN) w oparciu o dane o uszkodzeniach, które wystąpiły w ostatnich 11 latach działania elektrowni, dla wybranych grup urządzeń. Przewidywane daty wystąpienia uszkodzeń szacowano, po raz pierwszy w literaturze, biorąc pod uwagę zakład produkcyjny jako system, bez uwzględnienia sektora produkcyjnego. Plan obejmuje działania konserwacyjne, które mają być przeprowadzone przed przewidywanymi datami awarii, w celu zwiększenia wydajności wytwarzania energii, przedłużenia żywotności elektrowni, minimalizacji kosztów wytwarzania energii, maksymalizacji wskaźnika dostępności elektrowni oraz maksymalizacji zysków. Opracowany plan konserwacji wdrażano w omawianej elektrowni przez 2 lata. W tym okresie nie odnotowano przerw w pracy jednostek wytwórczych spowodowanych awarią rozważanych grup urządzeń, co oznacza, że wspomniane cele zostały osiągnięte.