Iranian Journal of Operations Research

Cost and revenue efficiency in DEA with production trade-offs

Javad Gerami

One of the ways to evaluate the performance of decision-making units (DMUs) such as banks and commercial companies is to use the concepts of economic efficiency in data envelopment analysis (DEA). In the process of evaluating the performance of the DMUs, it is important to apply the superior information of the decision maker (DM). In this paper, we obtain cost and revenue efficiency measurement models to evaluate DMUs based on the DM's opinion. In this regard, we use the method of production trade-offs in DEA. Using the production trade-off method, we apply the importance of inputs and outputs to the efficiency measurement process based on the opinion of the DM. We assumed that the cost (price) of each input (output) is different for different DMUs. We present the efficiency scores and efficient targets corresponding to the DMUs. We present an application of the presented models in the banking sector and present the results of the paper.

The application of multiple methodologies (problem structuring methods) in order to solve the problems of electricity shortage caused by cryptocurrency mining in Iran

hasan arabameri

Real-world decision makers are faced with different aspects of the world, and each of the types of hard and soft operations research methods have advantages for responding to certain aspects. Based on this, it can be claimed that by using two or more combined methods, more levels and dimensions of a problematic situation can be investigated and the results are definitely more reliable. The main goal of this research is to solve the problems of electricity shortage caused by cryptocurrency mining in Iran by combining three methods: Strategic choice Approach(SCA), Strategic Option Development and Analysis(SODA), Critical Systems Heuristics(CSH), while examining more detailed levels and dimensions of the problem, solutions or decisions should be adopted to be more reliable and more effective.The combination method is such that SCA is placed as the basis and platform of the research method, In the fourth and eighth steps of sca, soda and csh methods have been used, respectively. The results of this research show wider levels and dimensions of the problems and problems of electricity shortages caused by cryptocurrency mining and lead to the important point that the advantages and benefits of digital currencies should not be ignored due to electricity shortages.
Real-world decision makers are faced with different aspects of the world, and each of the types of hard and soft operations research methods have advantages for responding to certain aspects. Based on this, it can be claimed that by using two or more combined methods, more levels and dimensions of a problematic situation can be investigated and the results are definitely more reliable. The main goal of this research is to solve the problems of electricity shortage caused by cryptocurrency mining in Iran by combining three methods: Strategic choice Approach(SCA), Strategic Option Development and Analysis(SODA), Critical Systems Heuristics(CSH), while examining more detailed levels and dimensions of the problem, solutions or decisions should be adopted to be more reliable and more effective.The combination method is such that SCA is placed as the basis and platform of the research method, In the fourth and eighth steps of sca, soda and csh methods have been used, respectively. The results of this research show wider levels and dimensions of the problems and problems of electricity shortages caused by cryptocurrency mining and lead to the important point that the advantages and benefits of digital currencies should not be ignored due to electricity shortages.

A new approach on ‎fuzzy multiobjective multicommodity ‎minimal ‎cost ‎flow ‎problems

Ali Abbass Hadi

In this work, we consider a ‎multi-objective‎ ‎minimal ‎cost ‎flow (MMCF) ‎problem where there are several commodities to transport from‎ sources ‎to ‎destinations and there is more than one conveyance for those transporting. We also assume that in each conveyance, there are distinct capacities for each commodity. The obtained model is not necessary balanced, and we introduced a method to solve this model without converting it to a balanced model. Some advantages of the proposed method is discussed.

Bibliometric analysis and visualization of published research in emerging technologies

Hamid babaei Meybodi

With the expansion of emerging technologies, their applications have been introduced as a transformative factor in many industries and fields. However, these developments require more research in the area of new technologies. Nevertheless, few studies have comprehensively examined the published research in this field. In this regard, bibliometric studies, as one of the effective research methods in the field of emerging technologies, are a practical and effective tool in identifying research patterns, knowledge flows, study content, and key terms. Using this method, one can understand and briefly examine the scientific foundations and impact of emerging technologies. In summary, conducting bibliometrics in the field of emerging technologies can be used as an effective tool in identifying and analyzing research paths and the development of advanced technologies. In this context, articles published in the field of emerging technologies in the period 2013-2023 in various fields have been examined. The required data includes 13,263 articles extracted from the WOS database and were analyzed using Biblioshiny software under R-package. The obtained results include identifying influential authors, leading journals, organizations, and countries related to the field of emerging technologies. Additionally, using precise bibliometric analysis tools, the authors' collaboration network, thematic trends, most common terms, and citation network have been extracted. Finally, with the help of network analysis, key clusters in the existing literature have been identified based on research areas of new technologies.

Integrated Multi-Model Risk Assessment of an Aging Gas Pipeline Using Fuzzy AHP and 3D Uncertainty Matrix

Arman Gholinezhad Paji

The expansion of gas transmission lines in Iran involves numerous risks, requiring regular assessments to ensure safe and efficient transport. This study examines six kilometers of Iran’s oldest gas pipeline, located in Tonekabon, a densely populated and touristic city. The pipeline was divided into six zones, considering pipeline class, population density, and intersections. In each zone, three events—leakage, rupture, and explosion—were assessed using four methods: simple matrix, weighted matrix, fuzzy weighted matrix, and a 3D uncertainty-based matrix. Four experts evaluated the probability and severity of consequences, categorized as technical, safety, environmental, and cost impacts. The consequences enabled risk calculation across all categories. Standard deviation was used to compute a three-dimensional uncertainty-based risk, incorporating uncertainty in both probability and consequence estimation. Risk management levels were then adjusted accordingly. Chang’s fuzzy AHP method and Mamdani’s fuzzy logic in MATLAB were applied to handle inherent uncertainties. Results showed discrepancies between simple and fuzzy matrices due to the exclusion of cost impacts, given the state-owned nature of the company. The 3D matrix further indicated that most risk cells require only preliminary review, attributed to the company’s regular inspections and access to reliable data.

An $O(|V||E|^{2})$ Time Algorithm to Diagnose the Solvability of Single Rate $n$-Pair Networks with Common Bottleneck Links

Mehdi Ghiyasvand

Cai et al.(2013) and Cai and Han (2014) presented the polynomial time algorithms for two-pair and three-pair networks with common bottleneck links, respectively. Also, Chen and HaiBin(2012) proposed a non-polynomial time algorithms for $n$-pair networks with common bottleneck links, where $n$ is an arbitrary integer. This paper presents a new sufficient and necessary condition to determine the solvability of single rate $n$-pair networks with common bottleneck links, which concludes a polynomial time algorithm for $n$-pair networks with common bottleneck links, where $n$ is an arbitrary integer. Our algorithm runs in $O(|V||E|^{2})$ time, where $|V|$ and $|E|$ are the number of nodes and links, respectively.

Interval type-2 fuzzy backup 2-median location problem on trees

Fahimeh Baroughi

The backup 2-median location problem on a tree T is to deploy two servers at the vertices such that the expected sum of distances from all vertices to the set of functioning servers is minimum. In this paper, we investigate the backup 2-median location problem on tree networks with trapezoidal interval type-2 fuzzy weights. We first, present a new method for comparing generalized trapezoidal fuzzy numbers and then develop it for trapezoidal interval type-2 fuzzy numbers. Then numerical examples are given to compare the proposed methods with other existing methods. Finally, we apply our ranking method to solve the the backup 2-median location problem on a tree network with trapezoidal interval type-2 fuzzy weights.

Evaluating the extent of digital transformation in response to the public crisis: Evidence from Small Service Businesses

Jahanyar Bamdadsofi

During the COVID-19 pandemic and the resulting constraints, businesses have encountered changes in their customers’ behaviors and business environments. Scholars have emphasized on the role of digital transformation as a response to these challenges. This study investigates the level of digital maturity in seven dimensions of digital transformation presented by Kane (2017) in small service businesses (SSBs). A mixed method combining the logic of statistical accuracy of questionnaire analysis with the realistic aspects of discourse analysis was applied. The results revealed that digital transformation does not fully occur among the SSBs. Instead, some extent of digitalization happened in various areas such as communications with customers and the digitalization of some aspects of services. Besides, the study revealed that the most frequent pathways taken by SSBs toward digitalization are the less capital-intensive and technology-based ones . Furthermore, customers are involved in three types of relational activities categorized as “transactional”, “intercommunication”, and “information sharing”.