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This paper aims to propose a new linear parameter varying (LPV) controller for the robot tracking control problem. Using the identification of the robot dynamics in different work space points about modeling trajectory based on the least square of error algorithm, an LPV model for the robotic arm is extracted.

Parameter set mapping based on parameter component analysis results in a reduced polytopic LPV model that reduces the complexity of the implementation. An approximation of the required torque is computed based on the reduced LPV models. The state-feedback gain of each zone is computed by solving some linear matrix inequalities (LMIs) to sufficiently decrease the time derivative of a Lyapunov function. A novel smoothing method is used for the proposed controller to switch properly in the borders of the zones.

The polytopic set of the resulting gains creates the smooth switching polytopic LPV (SS-LPV) controller which is applied to the trajectory tracking problem of the six-degree-of-freedom PUMA 560 robotic arm. A sufficient condition ensures that the proposed controller stabilizes the polytopic LPV system against the torque estimation error.

Smoothing of the switching LPV controller is performed by defining some tolerances and creating some quasi-zones in the borders of the main zones leading to the compressed main zones. The proposed torque estimation is not a model-based technique; so the model variation and other disturbances cannot destroy the performance of the suggested controller. The proposed control scheme does not have any considerable computational load, because the control gains are obtained offline by solving some LMIs, and the torque computation is done online by a simple polytopic-based equation.

In this paper, a new SS-LPV controller is addressed for the trajectory tracking problem of robotic arms. Robot workspace is zoned into some main zones in such a way that the number of models in each zone is almost equal. Data obtained from the modeling trajectory is used to design the state-feedback control gain.

The purpose of this study is to identify the situation of spatial inequality in the residential system of Tehran city in terms of housing prices in the year 2021 and to examine its changes over time (1991–2021).

In terms of purpose, this study is applied research and has used a descriptive-analytical method. The statistical population of this research is the residential units in Tehran city 2021. The average per square meter of a residential unit in the level of city neighborhoods was entered in the geographical information system (GIS) in 2021. Moran’s spatial autocorrelation method, map cluster analysis (hot and cold spots) and Kriging interpolation have been used for spatial analysis of points. Then, the change in spatial inequality in the residential system of Tehran city has been studied and measured based on the price per square meter of a residential unit for 30 years in the 22 districts of Tehran by using statistical clustering based on distance with standard deviation.

The result of spatial autocorrelation analysis with a score of 0.873872 and a p-value equal to 0.000000 indicates a cluster distribution of housing prices throughout the city. The results of hot spots show that the highest concentration of hot spots (the highest price) is in the northern part of the city, and the highest concentration of cold spots (the lowest price) is in the southern part of Tehran city. Calculating the area and estimating the quantitative values of data-free points by the use of the Kriging interpolation method indicates that 9.95% of Tehran’s area has a price of less than US$800, 17.68% of it has a price of US$800 to US$1,200, 25.40% has the price of US$1,200 to US$1,600, 17.61% has the price of US$1,600 to US$2,000, 9.54% has the price of US$2,000 to US$2,200, 6.69% has the price of US$2,200 to US$2,600, 5.38% has the price of US$2,600 to US$2,800, 4.59% has the price of US$2,800 to US$3,200 and finally, the 3.16% has a price more than US$3,200. The highest price concentration (above US$3,200) is in five neighborhoods (Zafaranieh, Mahmoudieh, Tajrish, Bagh-Ferdows and Hesar Bou-Ali). The findings from the study of changes in housing prices in the period (1991–2021) indicate that the southern part of Tehran has grown slightly compared to the average range, and the western part of Tehran, which includes the 21st and 22nd regions with much more growth than the average price.

There is massive inequality in housing prices in different areas and neighborhoods of Tehran city in 2021. In the period under study, spatial inequality in the residential system of Tehran intensified. The considerable increase in housing prices in the housing market of Tehran has made this sector a commodity, intensifying the inequality between owners and non-owners. This increase in housing price inequality has caused an increase in the informal living for the population of the southern part. This population is experiencing a living situation that contrasts with the urban plans and policies.

This study aims to provide a bibliometric analysis and systematic literature review of Industry 4.0 (I4.0) research in the supply chain (SC) area and to understand related contemporary research trends. I4.0 has the potential to change the way goods are manufactured, distributed and made available to customers through the digitalisation of SC. Although I4.0 originated in 2011 in Germany, its application in managing the SC has only recently started gaining momentum. Therefore, it is essential to understand the research progress and identify the current trends of I4.0 application in the SC field.

A bibliometric analysis was conducted to empirically analyse the literature related to I4.0 implementation in the SC. This study retrieved papers from the Scopus database, reviewing 1,155 articles from the period 2016 to 2023 (November) for bibliometric analysis. Bibliometrix, using R software, was used for the bibliometric analysis, and VOSviewer was used for network analysis.

The findings provide an overview of the most relevant journals, most productive scholars, top academic institutions and top countries contributing to I4.0 research in the SC context. The results show that the most recent research contributions are related to the topics of SC performance, sustainability, digitalisation and digital transformation. Furthermore, a detailed review of articles published in the three and above-rated journals in the Chartered Association of Business Schools list is presented.

The novelty of this study lies in identifying the current research trends and themes of I4.0 research in the SC area. This research benefits researchers by identifying potential research areas for I4.0 implementation in the SC and providing directions for future research.

This research tries to find the blockchain-based resilience strategies that can help the supply chains of micro, small, and medium-sized enterprises (MSMEs) to recover from the disruptions and work effectively in a resource-based view perspective.

Eight broad strategies and 32 sub-strategies are identified from the literature review. Delphi study was carried out, and detailed discussion with 16 experts helped in finalizing these strategies. Further, the best-worst method (BWM) prioritized these strategies.

The findings suggests that “building social capital,” improving “coordination capabilities,” “sensitivity towards market,” “flexibility in process and production,” “reduction in process and lead time,”and “having a resource efficiency and redundancy” are the top strategies on which the top management should focus to overcome the situations of disruptions and enhance performance of MSMEs.

The blockchain-based strategies will enable the companies in tracing the products from the company to customers. Further, the customers will be able to identify their manufacturers, the raw materials used in manufacturing, and the life and quality of raw used materials. Altogether the textile industry will become more sensitive toward environmental practices.

The previous research has not identified and evaluated the blockchain-based resilience strategies, and therefore this study tries to fill this gap. This study used a smaller sample from the experts, so the results may vary if the larger data set is used and hypothesis testing can be done.

This study reviews scholarly work in sustainable green logistics and remanufacturing (SGLR) and their subdisciplines, in combination with bibliometric, thematic and content analyses that provide a viewpoint on categorization and a future research agenda. This paper provides insight into current research trends in the subjects of interest by examining the most essential and most referenced articles promoting sustainability and climate-neutral logistics.

For the literature review, the authors extracted and sifted 2180 research and review papers for the period 2008–2023 from the Scopus database. The authors performed bibliometric and content analyses using multiple software programs such as Gephi, VOSviewer and R programming.

The SGLR papers can be grouped into seven clusters: (1) The circular economy facets; (2) Decarbonization of operations to nurture a climate-neutral business; (3) Green sustainable supply chain management; (4) Drivers and barriers of reverse logistics and the circular economy; (5) Business models for sustainable logistics and the circular economy; (6) Transportation problems in sustainable green logistics and (7) Digitalization of logistics and supply chain management.

In this review, fundamental ideas are established, research gaps are identified and multiple future research subjects are proposed. These propositions are categorized into three main research streams, i.e. (1) Digitalization of SGLR, (2) Enhancing scopes, sectors and industries in the context of SGLR and (3) Developing more efficient and effective climate-neutral and climate change-related solutions and promoting more environmental-related and sustainability research concerning SGLR. In addition, two conceptual models concerning SGLR and climate-neutral strategies are developed and presented for managers and practitioners to consider when adopting green and sustainability principles in supply chains. This review also highlights the need for academics to go beyond frameworks and build new techniques and instruments for monitoring SGLR performance in the real world.

This study provides an overview of the evolution of SGLR; it also clarifies concepts, environmental concerns and climate change practices, particularly those directed to supply chain management.

The main goal of this paper is better understand the risk/return trade-off of investing in socially responsible investment funds (SRIF) and green investment funds (GIF).

To achieve our aim a green investment fund portfolio, a socially responsible investment portfolio and a conventional fund (CF) portfolio from the United States of America (USA) were selected to compare the efficiency of these three different portfolios, by using Value-Based Data Envelopment Analysis (DEA) methodology.

The results point out that SRIF and GIF are more efficient than CF. For five years, the CFs have not outperformed the GIF.

The results suggest that there is a growing awareness on the part of investors that sustainable companies are the companies that will allow a better quality of life and a more sustainable environment. It seems that somehow managers and investors are aware that the market will compensate them for thinking about a cleaner and more equitable world.

The paper examines contingent liabilities' effect on the firm's dividend decisions.

Fixed-effects regression and logit model results estimate the influence of contingent liabilities on firms' dividend decisions using a sample of 2,288 firm-year observations of S&P 500 firms from 2012 until 2022. Robustness checks and results from the 2SLS model further support the authors’ findings.

The results show that contingent liabilities negatively affect dividend payment decisions. This analysis further demonstrates that the stated effect of contingent liabilities on dividend decisions is more substantial for firms with financing deficits and those with above-industry-average corporate governance scores.

There needs to be more systematic conceptual reason for measuring uncertainty for firms and its influence on dividend decisions. Future research should use other measures of firm uncertainty to examine the relation of the firm's uncertainty with dividend decisions.

The authors suggest that contingent liabilities create uncertainty for future cash flows, influence a firm's agency costs and provide credible signals on a firm's prospects to the market. The findings support existing literature that measurable firm-specific variables significantly influence a firm's dividend decisions. The results are robust for an alternative explanation.

By investigating the impact of the influence of contingent liabilities on dividends, the authors extend research on dividend decisions and attempt to provide insights into a firm's dividend decisions by incorporating an off-the-balance sheet item (contingent liabilities) as a significant predictor for dividend decisions.

In the digital age, emerging technologies have affected every industry. Information and communications technology and digital technologies have transformed traditional supply chains into smart and more resilient ones, enabling effective management of challenges. Given the importance of the two topics, namely sustainable supply chain management and Industry 4.0 in supply chain management, on the one hand, and the dearth of theoretical research performed in this area on the other, this study aims to propose a conceptual model on a sustainable digital supply chain management in manufacturing companies.

This study utilized a qualitative approach. First, an in-depth review of the relevant literature was done. Then, following a multi-grounded theory methodology, relevant data were gathered by reviewing 92 papers and conducting nine semi-structured interviews with industry experts. These data were analyzed using the MAXQDA software.

A total of 41 concepts, ten sub-components and three main components (dimensions) were extracted, and the proposed conceptual model was presented. Finally, based on this conceptual model, three propositions were suggested.

Considering that the present study was performed in the context of Iranian manufacturing companies, caution should be exercised in relation to the generalizability of the obtained results. Also, due to the problems in the digital technology infrastructure and the limited use of these technologies by manufacturing companies (emphasized by the interviewees), this study focused on the theoretical dimension of using digital technologies by these companies.

The proposed comprehensive model can help academicians as well as practitioners to focus better and explore the variables and constructs of the model, paving the way toward successful implementation of digital technologies in the manufacturing supply chain.

To the best knowledge of the authors, this study is among the first of its kind which presents a holistic and comprehensive digital supply chain model aimed at guiding companies to consider sustainability from all the main dimensions and their relevant indicators.

The purpose of this paper is to determine the attractiveness or unattractiveness of cyberloafing in the workplace using Q methodology and the Kano model.

The perception of employees towards cyberloafing was investigated based on Q methodology, and then they were prioritized using Kano model. Ten IT companies were selected for the case study. In this study, a mixed method was used. First, 30 participants were interviewed. Next, after extracting the comments, Q-matrix was presented to 30 participants and they completed the matrix cells. Finally, Kano questionnaire was designed using the items obtained from Q methodology and distributed among 30 participants.

Q methodology led to nine perceptions, and the priorities of Kano model were proponents of increasing employees' dependence on the internet, economic thinkers, the indifferent, dissatisfied, proponents of receiving information, self-control proponents, the profit-minded, mind destroyer and satisfaction-oriented. Cyberloafing is considered unattractiveness with adverse effects. The combination of Q methodology and Kano model can improve the analysis of the results.

This study is one of the few studies in which Q methodology is improved by Kano model. In the past, Q methodology alone examined people’s perception, but by combining these two methods, it is determined which perception is more satisfying and which one is more important, and then a general result can be reached.

Despite promising conceptual developments in value co-creation behaviors, the scholarly attention afforded to the importance of the university website features in strengthening the university brand image and reputation through students’ value co-creation behaviors is limited. University website features are conceptualized as a hierarchical construct with three dimensions: usability, availability and information. This study aims to investigate the effect of university website features and value co-creation behaviors of students on promoting brand image and brand reputation at Islamic Azad University in Iran.

This study is quantitative. Using convenience sampling techniques, a responsive group of 384 students was chosen from the Islamic Azad University of Tehran in Iran. Survey methods were used for data collection. Partial least squares structural equation modeling was used to test the derived hypotheses.

The findings of this study indicated that website features have a positive effect on fostering value co-creation behaviors (participation and citizenship behavior), and participation behavior, in turn, improves university brand image and reputation. At the same time, among value co-creation behaviors, citizenship behavior has no impact on the university’s brand image. Finally, the brand image formed through website features and participation behavior positively affects brand reputation.

This study was conducted in the higher education (HE) sector in one cosmopolitan Iranian city (i.e. Tehran), to which Iranians from other cities travel for studying. Thus, the results of this survey include a variety of subcultures. In the future, a study that incorporates all major metropolitan cities of Iran may increase the generalizability of the findings. Unrelated to the purpose of this study, a future research study may extend the currently studied geographical dimensions and examine the antecedents of university brand reputation across different nations using a cross-cultural approach.

Pragmatically, the findings of this study urge university policymakers, information technology managers and marketers to consider the university website’s unique role in assisting co-creation behavior, which in turn promotes university brand image and reputation in the HE market. One of the ways to assess a university’s brand image and reputation is through the university ranking system. Ascending the ranking system can allow a university to attract qualified students.

These findings contribute to the marketing literature by empirically validating the three elements in the website features construct, providing intelligence on how website features can drive value co-creation behaviors, brand image and reputation. Also, results revealed that the brand image of universities positively affects brand reputation. This study highlights the importance of national and international rankings of universities and students’ sensitivity to such rankings. Undoubtedly, this is evident in Iranian students’ behavior in selecting their university.