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Senior managers are the customers of organizational performance measurement methods to help them make better decisions at the firm level. One of the most applicable methods is Network Data Envelopment Analysis (DEA). Network DEA models consider systems that have a network structure in which system inputs, after passing several intermediate interactions, are transformed into intermediate productions and finally leave the system as output products. However, many realworld cases do not necessarily conform to this network structure, which is related to the system outputs during multiple time periods or the same "dynamic" impacts. These structures cannot handle dynamic impacts. Therefore, this paper presents a novel structure that can consider the dynamic impacts and influences of sub-units on each other at various time periods. Besides, two models based on slack variables are proposed which can consider dynamic effects and calculate the efficiency of such networks. Using these models, the overall efficiency of networks is calculated for the whole time period. Finally, these models are applied to two examples, and the results obtained are compared with other methods. [ABSTRACT FROM AUTHOR]

One of the most valid definitions for the concept of "survival" is the possibility of paying salaries and wages to the startup's employees and owners for at least 42 months. Given that the highest failure rate of businesses is in the early years paying attention to the factors affecting new firms' performance processes will reduce their failure rate, leading to success, growth and sustainability. This article, reviews and analyzes all the articles in the Scopus database that are related to the survival of firms in terms of their number over time, the most common keywords, authors, journals, and countries publishing these articles, bibliometric method, and VOSviewer software are used. In the following, the factors that have been emphasized and repeated in the literature have been identified with a systematic literature review and meta-synthesis method. In the bibliometric section, 1959 articles have been analyzed and in the meta-synthesis review section, 85 articles have deeply been studied. Based on the findings of the research, 32 main factors affect the survival of businesses, which are categorized into five general categories including individual, organizational, supporters, financial, and environmental factors, and presented in a conceptual framework model. [ABSTRACT FROM AUTHOR]

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The present study aims to investigate the optimal fractional order PID controller performance in the chaotic system of HIV disease fractional order using the Particle Swarm optimization and Genetic algorithm method. Differential equations were used to represent the chaotic behavior associated with HIV. The optimal fractional order of the PID controller was constructed, and its performance in the chaotic system with HIV fractional order was tested. Optimization methods were used to get PID control coefficients from particle swarm and genetic algorithms. Findings revealed that the equations for the HIV disease model are such that the system's behavior is greatly inuenced by the number of viruses produced by infected cells, such that if the number of viruses generated by infected cells exceeds 202, the disease's behavior is such that the virus and disease spread. For varying concentrations of viruses, the controller created for this disease does not transmit the disease. [ABSTRACT FROM AUTHOR]

Considering the importance of small and medium-sized industrial units for economic growth, social cohesion, regional and local development, this study presents a model for the merger so that they can make use of each other's capacities and facilities to achieve higher efficiency levels. The involved criteria have been chosen using the SCOR model with the consideration of sustainability, resilience and agility criteria in each part of the supply chain network. PCA has been used to reduce the dimensionality and the efficiency of units has been determined by network DEA. Next, a mathematical model has been used to determine the best combination for merger. The model chosen for the finalization of the merger process is inverse network DEA, which tries to determine the final inputs of the merged units for a specific target. In addition to theoretical benefits, the results have practical applications. The results can give supply chain partners a common language for better communication and help them settle on standardized definitions. The model has been implemented using real-world data gathered from other articles, which pertain to 26 stone industries of Iran. The DEA model and the mathematical model have been solved through GAMS and the PCA approach through MATLAB. [ABSTRACT FROM AUTHOR]

Natural and man-made disasters have increased the attention of practitioners and researchers to vulnerability. Identifying business vulnerability is one of the basic elements of strategic analysis and public policy. The purpose of this paper is to explore evolutionary pathways to reduce the vulnerability of technology-based businesses. The intellectual structure of this subject was examined using both bibliometric co-occurrence and co-citation analyses. We focused on 629 articles published between 1981 and 2021. This article identifies four specific areas, namely business performance, small business vulnerability, sources of sustainability in business, and adaptation policy assessment. A novel framework was developed based on the most prominent papers identified in co-citation as well as the highly cited papers. The proposed model includes drivers, vulnerability appearance, and vulnerability reduction. This study examines the basis of research concepts, themes, and communities in reducing the vulnerability of technology-based businesses. This article identifies business vulnerability as one of the relevant areas to disaster economics and sustainability studies. [ABSTRACT FROM AUTHOR]