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In this study, the performance analysis of the split flow turbofan engine with afterburners has been examined using the parametric cycle analysis method. The purpose of this study is to examine how engine performance is impacted by design parameters and flight ambient values and to develop a software in this context.

Software has been developed using the open-source PYTHON programming language to perform performance analysis. Mach number, compressor/fan pressure ratio, bypass ratio and density were used as parameters. The effects of these variables on engine performance parameters were investigated.

Parametric cycle analysis has been calculated for different flight conditions in the range of 0–2 M and 0–15,000 m altitude for turbofan engines. With this study, basic data were obtained to optimize according to targeted flight conditions.

As a result of the performance analysis, the association between the flight conditions and design parameters of engine were determined. A software has been developed that can be used in the design of supersonic gas turbine engines for fast and easy simulation of the design parameters.

The variables used in the literature have been analyzed, and the results of the studies have been incorporated into the developed software, which can be used in innovative engine design. Software is capable to be developed further with the integration of new algorithms and models.

This study aims to investigate supply network (SN) resilience capabilities across the organizational, supply chain (SC) and industry levels by drawing on the complex adaptive systems (CASs) theory and the social–ecological perspective of resilience. An empirically grounded framework operationalizes the concept of social–ecological resilience by expounding resilience capabilities across phases of the CAS adaptive cycle.

This research uses a qualitative multiple case study approach. It draws on the case of the Australian Defence Manufacturing SN (ADM SN) during COVID-19 disruptions. A total of 28 interviews with senior decision makers from 17 companies, complemented by 5 interviews with the Australian Defence SC organizations and secondary data analysis, support the findings.

Individual organizations’ SC visibility and flexibility enabled by effective risk management and collaboration enhance the ability of the SN to anticipate and prepare for disruption. At the same time, the strength of SC relationships reduces resilience. SN disruption response velocity is enabled by inventory redundancy, process flexibility at the organizational level and visibility and collaboration at the SC level. Institutional support at the national industry level, development of value-adding capabilities and manufacturing process flexibility at the organizational level enhances the SN’s ability to re-organize. The transition from hierarchical to decentralized collaborative governance enhances SN resilience.

From a practitioner’s perspective, the findings highlight the need to embrace a broader view of SC beyond immediate tiers. Decision-makers in multinational companies must recognize the long-term impact of their procurement decisions on the supplier ecosystem. Developing local supplier capabilities rather than relying on established global SCs will pay off with future resilience. It, however, demands substantial investment and radical changes across all SC tiers. The lesson for smaller firms is not to over-rely on the existing relationships with supply partners. Although trust-based relationships and collaboration are essential, over-commitment can be counterproductive during global disruptions. With a lack of visibility and control over the SC, operational flexibility is critical for small firms to adapt to shifts in supply and demand.

To the best of the authors’ knowledge, this empirical research is one of the first attempts to operationalize the social–ecological perspective of SN resilience. Evidence-based theoretical propositions contribute to the emerging conversation about the CAS nature of resilience by demonstrating the multi-level effects of resilience capabilities.

This study aims to develop theory on the process toward digital service innovation (DSI) and to generate insights into how companies deal with the rising complexity associated with DSI, both inside and outside of the organization, through organizational learning and alignment.

After purposeful sampling, in-depth, longitudinal case studies of three manufacturers are presented as illustration. Per case, multiple semi-structured interviews are conducted, and insights are validated through rich additional data gathering. Each company's DSI pathway is reconstructed with critical incident technique. Next, using systematic combining, a middle-range theory is developed by proposing a theoretical frame concerning the relations between DSI maturity, learning and alignment.

The authors posit that, as companies gradually develop and progress toward DSI maturity, they deal with a rising degree of complexity, fueling their learning needs. Companies that are apt to learn, pass through multiple cycles of learning and alignment to overcome specific complexities associated with different DSI stages, with each cycle unlocking new DSI opportunities and challenges.

The study applies a stage-based view on DSI combined with complexity management and organizational learning and alignment theory. It offers a theoretical frame and propositions to be used by researchers for future DSI studies and by managers to evaluate alternative DSI strategies and implementation steps.

The study aims to equip robots with the ability to precisely maintain interaction forces, which is crucial for tasks such as polishing in highly dynamic environments with unknown and varying stiffness and geometry, including those found in airplane wings or thin, soft materials. The purpose of this study is to develop a novel adaptive force-tracking admittance control scheme aimed at achieving a faster response rate with higher tracking accuracy for robot force control.

In the proposed method, the traditional admittance model is improved by introducing a pre-proportional-derivative controller to accelerate parameter convergence. Subsequently, the authors design an adaptive law based on fuzzy logic systems (FLS) to compensate for uncertainties in the unknown environment. Stability conditions are established for the proposed method through Lyapunov analysis, which ensures the force tracking accuracy and the stability of the coupled system consisting of the robot and the interaction environment. Furthermore, the effectiveness and robustness of the proposed control algorithm are demonstrated by simulation and experiment.

A variety of unstructured simulations and experimental scenarios are designed to validate the effectiveness of the proposed algorithm in force control. The outcomes demonstrate that this control strategy excels in providing fast response, precise tracking accuracy and robust performance.

In real-world applications spanning industrial, service and medical fields where accurate force control by robots is essential, the proposed method stands out as both practical and straightforward, delivering consistently satisfactory performance across various scenarios.

This research introduces a novel adaptive force-tracking admittance controller based on FLS and validated through both simulations and experiments. The proposed controller demonstrates exceptional performance in force control within environments characterized by unknown and varying.

Although strategic scholars have made great effects to exploring the moderating roles of team interaction in explaining the effect of top management team (TMT) diversity, they have adopted seemingly conflicting theoretical perspectives to explain how it works. Drawing on ideas from the threat rigidity theory, the authors integrated these perspectives by proposing a contingency model in which the relationships between TMT diversity and adaptive firm performance depend on the matching between the internal context (i.e. overlapping team tenure) and external context (i.e. severity of threat).

This study sampled 579 Chinese A-share listed companies that have been severely affected by the COVID-19 pandemic, and multilevel linear regression analysis was used to test the hypothesis.

Results provided support for this hypothesis. Specifically, the interaction between TMT age/tenure diversity and overlapping team tenure is significant only when the severity of threat is high, while the interaction between TMT functional diversity and overlapping team tenure is significant only when the severity of threat is low.

The results of this study provide a comprehensive perspective to predict the performance impact of team diversity and contribute to diversity research and practice.

Climate variability, accompanied by rapid urbanization and rising population disproportionality, impacts urban poor settlements. This paper aims to analyse the climate resilience for the urban poor in Ahmedabad through the lens of WASH development strategies. To assess the adaptive capacities of urban poor communities, a framework in the form of a vulnerability matrix has been used consisting of four key parameters – tenure, basic services, mobilization and partnership and disaster management capacities. The matrix implicitly recommends area-specific interventions to boost adaptive capacities and improve resilience based on WASH services.

This paper was designed to assess the climate resilience of WASH services in the urban poor settlements of Ahmedabad city. In all, seven slums were selected using a stratified sampling approach considering topography, access to WASH services and urban heat island effect. These slums were then assessed using a theoretical framework having four key parameters – tenure, basic service, mobilization and partnership and disaster management capacities. The data for the analysis was collected from both secondary and primary sources. For the latter, semi-structured interviews with key stakeholders, observational field visits and focused group discussions with the communities were done.

A ladder form of assessment matrix was derived from a thorough literature review and various pre-existing theories. This matrix consists of four key parameters – tenure, basic service, mobilization and partnership and disaster management capacities. The slums were evaluated by applying this framework, and direct and indirect relationships were established between the said parameters.

This paper was adapted in the light of various obstacles put forward by the Covid-19 pandemic. Some of the interviews with the bureaucrats and external researchers were conducted online, while the engagement with the slum dwellers was in-person, considering appropriate social and/or physical distancing norms. Implications of the Covid-19 second wave restricted the involvement of researchers with the communities at an ethnographic level.

The ladder form of vulnerability assessment framework has been developed and contextualized using the insights from literature review, field visits and multi-stakeholder consultations. It was helpful in identifying aspects that require suitable interventions for improving and imparting resilience among the urban poor settlements. The learnings from this paper are significant for planners and decision-makers in identifying and prioritizing context-specific future projects for a city.

This study aims to further develop the CLC stage/path’s identification model that distinguishes between path’s emergence (emergence stage), path’s development (growth stage), path’s sustainment (maturity stage), path’s decline (decline stage) and path’s transformation (renewal stage), and by applying it, define the current stage/path of the Demarcated Douro Region (DDR) cluster. The Port wine industry, which is the dominant industry of the DDR cluster, is at the maturity/decline stage – is the same for the cluster itself?

It is a case study with a longitudinal perspective based on the analysis of the dynamics of the parameters of cluster evolution using available secondary sources (cluster identity/brand; number of firms; number of employees; network; innovation; policies and regulations; and external markets – exports), especially addressing the past decade, that represent the stage of maturity/decline of the cluster’s dominant Port wine industry.

The conclusion is that since the 1990s the Demarcated Douro Region has gone through a “path transformation” where during the following 20 years new “anchors” for the cluster were gradually introduced, such as Doc Douro Wines, new forms of consumption of Port wine, tourism and olive oil. Since 2010 the cluster has entered a growth stage/(new) path’s development, where these “anchors” are in steady growth. The Douro brand is becoming more internationally recognized and established, the number of firms and employees is increasing, the network is restructuring with the creation of cluster-specific official institutions, innovation is especially reflected with increasing heterogeneity through diversification of the clusters into new activities and regulations and policies are supportive for expansion – all these parameters are indicating the rise of the new cycle for the cluster. Thus, the DDR cluster represents an attractive business environment and requires attention from regional policymakers to support the cluster’s development. Especially institutions have been highlighted as internal factors driving clusters growth, European integration as an external factor and firms’ strategies of diversification and internationalization as an appropriate de-locking mechanism for new path’s development.

This research contributes to the CLC theory by further developing and applying a CLC stage/path identification model. It provides a better understanding of the dynamics of the DDR cluster that diverge from its dominant industry life cycle, which is relevant for regional policies and firms’ strategies. This study has its limitations. It provides an exploratory application of the theoretical framework proposed, and consequently, no general conclusions are possible yet. More empirical studies with different clusters in different stages are necessary to test the framework.

These findings are useful to policymakers when designing their policies for cluster development but also for clusters’ entities and actors when making their strategic decisions as it allows based on the verification of the established parameter of CLC to identify its current stage/path of development.

The paper presents a theoretically grounded model for CLC identification and for the first time to the best of the authors’ knowledge applies it to a cluster case – the DDR cluster. This case applies the proposed model and illustrates its usefulness. The model provides the tools for a better understanding of cluster dynamics.

Cross-layer approach in media access control (MAC) layer will address interference and jamming problems. Hybrid distributed MAC can be used for simultaneous voice, data transmissions in wireless sensor network (WSN) and Internet of Things (IoT) applications. Choosing the correct objective function in Nash equilibrium for game theory will address fairness index and resource allocation to the nodes. Game theory optimization for distributed may increase the network performance. The purpose of this study is to survey the various operations that can be carried out using distributive and adaptive MAC protocol. Hill climbing distributed MAC does not need a central coordination system and location-based transmission with neighbor awareness reduces transmission power.

Distributed MAC in wireless networks is used to address the challenges like network lifetime, reduced energy consumption and for improving delay performance. In this paper, a survey is made on various cooperative communications in MAC protocols, optimization techniques used to improve MAC performance in various applications and mathematical approaches involved in game theory optimization for MAC protocol.

Spatial reuse of channel improved by 3%–29%, and multichannel improves throughput by 8% using distributed MAC protocol. Nash equilibrium is found to perform well, which focuses on energy utility in the network by individual players. Fuzzy logic improves channel selection by 17% and secondary users’ involvement by 8%. Cross-layer approach in MAC layer will address interference and jamming problems. Hybrid distributed MAC can be used for simultaneous voice, data transmissions in WSN and IoT applications. Cross-layer and cooperative communication give energy savings of 27% and reduces hop distance by 4.7%. Choosing the correct objective function in Nash equilibrium for game theory will address fairness index and resource allocation to the nodes.

Other optimization techniques can be applied for WSN to analyze the performance.

Game theory optimization for distributed may increase the network performance. Optimal cuckoo search improves throughput by 90% and reduces delay by 91%. Stochastic approaches detect 80% attacks even in 90% malicious nodes.

Channel allocations in centralized or static manner must be based on traffic demands whether dynamic traffic or fluctuated traffic. Usage of multimedia devices also increased which in turn increased the demand for high throughput. Cochannel interference keep on changing or mitigations occur which can be handled by proper resource allocations. Network survival is by efficient usage of valid patis in the network by avoiding transmission failures and time slots’ effective usage.

Literature survey is carried out to find the methods which give better performance.

The purpose of this study is to examine various key aspects associated with entrepreneurs’ behaviour following a long-term crisis. Specifically, the study compares the perceptions of female and male entrepreneurs operating in Cyprus and Greece concerning success factors and firm performance in the aftermath of the global financial crisis. Conceptually, the study considers the organisational adaptation literature (Miles and Snow’s typology).

The views of female and male micro and small firm owners-managers operating in Greece and Cyprus, a total of 406, were gathered through a questionnaire. To analyse the quantitative data, independent samples t-test and exploratory factor analysis were applied.

Participants’ responses reveal similar levels of perceived importance between genders regarding adaptive measures and strategies to confront a long-term crisis, as well as perceived firm performance. Nevertheless, exploratory factor analysis highlights differences in how male/female entrepreneurs perceive actions that, as in the case of financial management, can safeguard the immediate outlook of the firm.

While scholarly discourses on gender and entrepreneurship abound, important knowledge gaps still exist, for instance, in entrepreneurs’ problem-solving strategies adopted by female and male entrepreneurs following crises. In addressing this scholarly gap cross-culturally, that is, drawing on cross-national data (Cyprus and Greece); the present study makes an important contribution. Empirically, the study ascertains similar entrepreneurial behavioural characteristics between female-male entrepreneurs. Theoretically, the study validates Miles and Snow’s typology and develops a theoretical framework linking the typology and dimensions emerging from the empirical findings.

This paper aims to provide an examination of the use of the concept of resilience and its use in service organisation, ecosystem-related literature and the wider social sciences.

This paper provides a critical review and commentary on the resilience literature in the social and business sciences and its relevance to service organisations.

Two main approaches towards resilience are identified (engineering and socio-ecological resilience) with each having different assumptions about the nature of resilience with corresponding implications for policymaking, indicator selection and application in a service context. These approaches operate at different scales and possess different properties with respect to the likelihood of enacting transformative service marketing.

Different conceptualisations of resilience have profound implications for resilience-related policymaking as well as understanding change and adaptation in service ecosystems and organisations.

The transformative possibilities of resilience are connected to the active enhancement and construction of social capacity by service organisations and the persistent resilience of the resilience concept.

This paper highlights the importance of clearly defining the resilience concept and its implications for research and transformative service organisations.