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This paper focuses mainly on the experimental and in‐flight spin investigations for an executive light airplane, named I‐23 and built in the Institute of Aviation (Warsaw, Poland). It is a single‐engine, all composite, straight wing, retractable undercarriage, conventional configuration and flight control system airplane. In‐flight spin tests confirmed good rudder and elevator effectiveness for spin recovery in a wide range of positions of the center of gravity. A typical time history of a spin entry and the developed spin and recovery is shown as well.

The purpose of this paper is to present an approach to a polar graph measurement by a flight testing technique and to propose a baseline research method for future tests of UAV polar graphs. The method presented can be used to demonstrate a conceptual and preliminary design process using a scaled, unmanned configuration. This shows how results of experimental flight tests using a scaled flying airframe may be described and analysed before manufacturing the full scale aircraft.

During the research, the flight tests were conducted for two aerodynamic configurations of a small UAV. This allowed the investigation of the influence of winglets and classic vertical stabilizers on the platform stability, performance and therefore polar graphs of a small unmanned aircraft.

A methodology of flight tests for the assessment of a small UAV’s polar graph has been proposed, performed and assessed. Two aerodynamic configurations were tested, and it was found that directional stability had a large influence on the UAV’s performance. A correlation between the speed and inclination of the altitude graph was found – i.e. the higher the flight speed, the steeper the altitude graph (higher descent speed, steeper flight path angle). This could be considered as a basic verification that the recorded data have a physical sense.

The polar graph and therefore glide ratio of the aircraft is a major factor for determining its performance and power required for flight. Using the right flight test procedure can speed-up the process of measuring glide ratio, making it easier, faster, robust, more effective and accurate in future research of novel, especially unorthodox configurations. This paper also can be useful for the proper selection of requirements and preliminary design parameters for making the design process more economically effective.

This paper presents a very efficient method of assessing the design parameters of UAVs, especially the polar graph, in an early stage of the design process. Aircraft designers and producers have been widely performing flight testing for years. However, these procedures and practical customs are usually not wide spread and very often are treated as the company’s “know how”. Results presented in this paper are original, relatively easily be repeated and checked. They may be used either by professionals, highly motivated individuals and representatives of small companies or also by ambitious amateurs.

The purpose of this paper is to describe an integrated approach to spin analysis based on 6-DOF (degrees of freedom) fully nonlinear equations of motion and a three-dimensional multigrid Euler method used to specify a flow model. Another purpose of this study is to investigate military trainer performance during a developed phase of a deliberately executed spin, and to predict an aircraft tendency while entering a spin and its response to control surface deflections needed for recovery.

To assess spin properties, the calculations of aerodynamic characteristics were performed through an angle-of-attack range of −30 degrees to +50 degrees and a sideslip-angle range of −30 degrees to +30 degrees. Then, dynamic equations of motion of a rigid aircraft together with aerodynamic loads being premised on stability derivatives concept were numerically integrated. Finally, the examination of light turboprop dynamic behaviour in post-stalling conditions was carried out.

The computational method used to evaluate spin was positively verified by comparing it with the experimental outcome. Moreover, the Euler code-based approach to lay down aerodynamics could be considered as reliable to provide high angles-of-attack characteristics. Conclusions incorporate the results of a comparative analysis focusing especially on comprehensive assessment of output data quality in relation to flight tests.

The conducted calculations take into account aerodynamic and flight dynamic interaction of an aerobatic-category turboprop in spin conditions. A number of manoeuvres considering different aircraft configurations were simulated. The computational outcomes were subsequently compared to the results of in-flight tests and the collected data were thoroughly analysed to draw final conclusions.

This study aims to identify the driving factors that influence blockchain technology adoption in the context of a supply chain (SC), considering three dimensions: technology, transactions and collaboration.

An integrative systematic literature review of previous studies was conducted. Using three main dimensions: technology, transactions and SC collaboration, supported by the unified theory of acceptance and use of technology, transaction cost economics (TCE) and concepts of SC collaboration, the authors categorized factors that contributed to blockchain technology in SC in the extant literature and proposed a theoretical model that covers these three dimensions.

The findings reveal that the information sharing category – related to the SC collaboration dimension – is the category with the greatest number of motivating factors for blockchain adoption in the SC context, followed by performance expectancy and behavioral uncertainty.

The review considers papers published until 2021 obtained from a specific database.

This study focuses on filling the research gap concerning technology adoption as it considers the interconnection formed by two organizations, interorganizational transactions and SC collaboration, using complementary theories to explain the phenomenon.

This research aims to investigate the role of digitalization in facilitating the integration of circular economy (CE) principles within a firm operating in the Italian agrifood sector. The study seeks to explore the evidence and effects emerging from the adoption of digital technologies in a small and medium enterprise (SME) operational setting.

An interpretative case study was conducted on an SME operating in the Italian agrifood sector. The selected firm is known to adopt a business model oriented towards circularity by using entirely digitized closed-loop hydroponic cultivation.

The findings reveal that the digitalization of the production process, supported by an integrated information system, enables optimizing the use and consumption of natural resources and minimizes waste during the production stage. Additionally, the authors observed that digitalization triggers a complex mechanism of interaction between various firm factors, market dynamics and forms of institutionalization, which are intrinsically intertwined with the concepts of sustainability and resilience in the agrifood sector.

From a theoretical point of view, the interpretive reading key – historically appropriate to embrace the complexity of the phenomena under study – can foster a deeper understanding of the dynamics underlying digitalization as an enabling factor to facilitating the adoption of CE principles in the agrifood sector. Regarding managerial implications, the study contributes to the debate on the importance of digital transition in the agrifood industry, which in the Italian context shows considerable resistance due, especially, to the size of the firms (mainly SMEs and micro) and managerial conservatism tradition.

The purpose of this study is to evaluate food supply chain stakeholders’ intention to use Industry 5.0 (I5.0) drones for cleaner production in food supply chains.

The authors used a quantitative research design and collected data using an online survey administered to a sample of 264 food supply chain stakeholders in Nigeria. The partial least square structural equation model was conducted to assess the research’s hypothesised relationships.

The authors provide empirical evidence to support the contributions of I5.0 drones for cleaner production. The findings showed that food supply chain stakeholders are more concerned with the use of I5.0 drones in specific operations, such as reducing plant diseases, which invariably enhances cleaner production. However, there is less inclination to drone adoption if the aim was pollution reduction, predicting seasonal output and addressing workers’ health and safety challenges. The findings outline the need for awareness to promote the use of drones for addressing workers’ hazard challenges and knowledge transfer on the potentials of I5.0 in emerging economies.

To the best of the authors’ knowledge, this study is the first to address I5.0 drones’ adoption using a sustainability model. The authors contribute to existing literature by extending the sustainability model to identify the contributions of drone use in promoting cleaner production through addressing specific system operations. This study addresses the gap by augmenting a sustainability model, suggesting that technology adoption for sustainability is motivated by curbing challenges categorised as drivers and mediators.

All firms' business models are based on their interdependencies with other parties in their ecosystems. The Internet of Things (IoT) is beginning to fundamentally disrupt the agri-food industry, forcing the ecosystem to change. When an ecosystem is transforming, the interdependencies among its actors can create friction. Technology providers and core actors should consider these interdependencies as they update their strategies for value creation and capture. The purpose of the present research is to consider what it might take for agri-food firms to capitalize on these interdependencies by moving from traditional business models to business models based on collaboration and open innovation.

The present paper draws on data from four online focus groups that we created to discuss how to co-create the business models agri-food firms need in a constantly changing environment. The paper presents an application of phenomenon-driven research (PDR), an engaged methodology. The study method enables novel pathways to develop and implement innovative solutions. This study draws on the interaction of theory and practice and involves multiple stakeholders with varying roles in the agri-food ecosystem.

The authors found that any open innovation setup in agri-food needs to constantly reconfigure itself to balance the needs of farmers and the needs of the market. This interplay can only support the IoT-enabled ecosystem if continuous interaction and negotiation occur among various stakeholders of the food system. When the farmers' needs and the market's needs are aligned, the space for developing a collaborative and open business model is prepared.

The insights gained from this study inspire action and commitment to common goals when developing collaboration-based business models (CBMs). The paper offers insights for players in the agri-food industry who are considering CBMs in the course of digital transformation.