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The purpose of this paper is to present the synthesis of a robust controller for autonomous small‐scale helicopter hovering control using extended H_∞ loop shaping design techniques.

This work presents the development of a robust controller for smooth hovering operation required for many autonomous helicopter operations using H_∞ loop shaping technique incorporating the Vinnicombe‐gap (v‐gap) metric for validation of robustness to uncertainties due to parameter variation in the system model. Simulation study was conducted to evaluate the performance of the designed controller for robust stability to uncertainty, disturbance rejection, and time‐domain response in line with ADS‐33E level 1 requirements.

The proposed techniques for a robust controller exhibit an effective performance for both nominal plant and 20 percent variation in the nominal parameters in terms of robustness to uncertainty, disturbance wind gust attenuation up to 95 percent, and transient performance in compliance with ADS‐33E level 1 specifications.

The controller is limited to hovering and low‐speed flight envelope.

This is expected to provide efficient hovering/low‐speed autonomous helicopter flight control required in many civilian unmanned aerial vehicles applications. Also, the technique can be used to simplify the number of robust gain‐scheduled linear controllers required for wide‐envelope flight.

The research will facilitate the deployment of low cost, small‐scale autonomous helicopters in various civilian applications.

The research addresses the challenges of parametric variation inherent in helicopter hovering/low‐speed control using an extended H_∞ loop shaping technique with v‐gap metric.

The purpose of this paper is to develop a multiobjective differential evolution (MODE)-based extended H-infinity controller for autonomous helicopter control.

Development of a MATLAB-based MODE suitable for controller synthesis. Formulate the H-infinity control scheme as an extended H-infinity loop shaping design procedure (H _∞ -LSDP) with incorporation of v-gap metric for robustness to parametric variation. Then apply the MODE-based algorithm to optimize the weighting function of the control problem formulation for optimal performance.

The proposed optimized H-infinity control was able to yield set of Pareto-controller candidates with optimal compromise between conflicting stability and time-domain performances required in autonomous helicopter deployment. The result of performance evaluation shows robustness to parameter variation of up to 20 per cent variation in nominal values, and in addition provides satisfactory disturbance rejection to wind disturbance in all the three axes.

The formulated H-infinity controller is limited to hovering and low speed flight envelope. The optimization is focused on weighting function parameters for a given fixed weighting function structure. This thus requires a priori selection of weighting structures.

The proposed MODE-infinity controller algorithm is expected to ease the design and deployment of the robust controller in autonomous helicopter application especially for practicing engineer with little experience in advance control parameters tuning. Also, it is expected to reduce the design cycle involved in autonomous helicopter development. In addition, the synthesized robust controller will provide effective hovering/low speed autonomous helicopter flight control required in many civilian unmanned aerial vehicle (UAV) applications.

The research will facilitate the deployment of low-cost, small-scale autonomous helicopter in various civilian applications.

The research addresses the challenges involved in selection of weighting function parameters for H-infinity control synthesis to satisfy conflicting stability and time-domain objectives. The problem of population initialization and objectives function computation in the conventional MODE algorithm are addressed to ensure suitability of the optimization algorithm in the formulated H-infinity controller synthesis.

A growing body of literature has begun in the direction of supply chain performance measurement. However, selecting the appropriate set of key performance indicators (KPIs) for measuring supply chain performance have always remained a challenge. The purpose of this paper is to identify the KPIs and categorize them specifically for measuring retail supply chain performance.

A qualitative approach, based on literature has been adopted. Published literature from refereed journals on supply chain performance measurement has been considered and various approaches for developing KPIs have been studied to develop a theoretical framework for performance measurement in retail supply chain.

The paper identifies key indicators for performance measurement and classifies them into four major categories: transport optimization, information technology optimization, inventory optimization and resource optimization. These key indicators are arranged precisely for retail industry. A theoretical framework is proposed to link the performance of these constructs on financial performance of the firm.

Future research can be carried out to validate the relevance and applicability of identified indicators. The study can be further conducted to measure the interrelationships between the KPIs and their impact on financial performance of the firm.

This study proposes a list of indicators for retail industry, which are presented in appropriate categories so that it can be used by the focussed teams for further improvement.

To the best of authors’ knowledge, no other study has categorized the KPIs into groups, specifically for measuring retail supply chain performance. The researcher also intends to carry out further empirical study to test the proposed theoretical framework.

Non-fungible tokens (NFTs) are gaining popularity as investments and personal indulgences, prompting brands to integrate them into marketing campaigns. Thus, understanding consumer personality traits toward NFTs is essential for success. This study presents a model that explores how social comparison orientation (SCO) influences perceived exclusivity and financial benefits of NFT marketing, subsequently impacting experiential evaluations, willingness to purchase NFTs and brand loyalty.

We conducted two experiments to test our model. Study 1 used a quasi-experiment with 1,053 participants and tested the model using partial least squares–based structural equation modeling. In Study 2, we aimed to investigate the causal influence of SCO on NFT marketing effectiveness. We employed a one-factor experiment (social comparison prime: high SCO vs. control) with 123 participants.

NFT users frequently engage in social comparisons and prefer branded NFTs that offer exclusivity (social value) and financial benefits (economic value). Social and financial superiority derived from NFTs enhances branded NFT experiences, leading to a stronger willingness to purchase NFTs and building brand loyalty. Perceived exclusivity, financial benefits and experiential evaluation mediate the effects of SCO on willingness to purchase NFTs and brand loyalty.

This study explores the effectiveness of NFT marketing through the lens of social comparison theory. In doing so, we examined the relationship between SCO and NFT marketing outcomes, revealed the causal influence of SCO on perceived exclusivity and perceived benefits in NFT marketing and shed light on the serial mediation of value- and experience-related constructs.

The purpose of this paper is to identify the quality initiatives implemented in UK manufacturing small and medium‐sized enterprises (SMEs) and to perform a comparative analysis of quality management practices within Six Sigma firms against the non‐Six Sigma manufacturing SMEs.

To achieve the research objective, a survey‐based approach is adopted by designing a short questionnaire addressing the issues of quality practices in SMEs. The paper encompasses the survey results from the first phase of Doctoral study to identify Six Sigma and non‐Six Sigma companies.

The response rate from the survey is 12.7 per cent out of 500 companies identified through the use of random sampling technique within the FAME and Dun & Bradstreet database of manufacturing SMEs. Data analysis was carried out using SPSS and Microsoft Excel. The findings from the study reveal that there is a significant difference in the performance of the Six Sigma/Lean firms against ISO certified companies. However, it is interesting to reflect on the findings of critical success factors (CSFs) of the sample firms. There is no significant difference in the perceived importance of the identified CSFs' variables in the Six Sigma and ISO certified SMEs.

The focus of the study is only on UK manufacturing SMEs encompassing 64 firms. The small sample size and focus on manufacturing sector limits its generalisability to the entire SME population. Future study should focus on performing a comparative study of manufacturing and service based SMEs in UK or Europe.

The novelty of the paper lies in conducting a comparative study on the performance of Six Sigma and non‐Six Sigma UK SMEs and drawing out valuable lessons for academics, consultants, researchers and practitioners of continuous improvement initiatives like Lean and Six Sigma.

The essence of benchmarking is the process of identifying the highest standards of excellence for products, services, or processes, and then making the improvements necessary to reach those standards – commonly called “best practices”. Various companies have adopted benchmarking and customized the methodology to suit their needs. A five‐step benchmarking model is suggested in this paper as a model to be used when undertaking a benchmarking study. Two case studies are enumerated and a comparison presented.

A gap between research and practice is commonly perceived throughout accounting academia. However, empirical evidence on the magnitude of this detachment remains scarce. The authors provide new evidence to the ongoing debate by introducing a novel topic-based approach to capture the research-practice gap and quantify its extent. They also explore regional differences in the research-practice gap.

The authors apply the unsupervised machine learning approach Latent Dirichlet allocation (LDA) to compare the topical composition of 2,251 articles from six premier research, practice and bridging journals from the USA and Europe between 2009 and 2019. The authors extend the existing methods of summarizing literature and develop metrics that allow researchers to evaluate the research-practice gap. The authors conduct a plethora of additional analyses to corroborate the findings.

The results substantiate a pronounced topic-related research-practice gap in accounting literature and document its statistical significance. Moreover, the authors uncover that this gap is more pronounced in the USA than in Europe, highlighting the importance of institutional differences between academic communities.

The authors objectify the debate about the extent of a research-practice gap and stimulate further discussions about explanations and consequences.

To the best of the authors' knowledge, this is the first paper to deploy a rigorous machine learning approach to measure a topic-based research-practice gap in the accounting literature. Additionally, the authors provide theoretical rationales for the extent and regional differences in the research-practice gap.

Internet and electronic networks tend to be used to provide customers with services and to facilitate understanding of common variable demands by which many organizations may increase services' quality from the customers' point of view. In addition, e‐libraries, though in some ways run for noncommercial goals, have been faced with great attention from customers, which makes them maintain and develop their services. The authors have come to a conclusion that the only way to increased financial benefits is through better service. Organizations as a part of the domestic information community therefore, have turned to implementation of new methods such as management of customer relationships. This paper aims to develop a valid and reliable method for evaluating and measuring the management relationship level with customers in e‐libraries. In addition, the research tries to find how successful Yazd University Libraries has been to meet students' expectations, as a guideline to take steps toward improving its services.

The research was conducted among 381 e‐library services users in Yazd University, using a questionnaire comprised of 78 items. Moreover, exploratory factor analysis was used to classify the CRM attributes into latent “CRM factors”. Finally, the study measures the gap between users' expectations and perceptions about each CRM factor at Yazd University.

The paper found only 37 of 78 items suitable enough to be used for CRM measurement in e‐libraries. Results of factor analyzing show that there are three main factors in e‐libraries' CRM; two of them may need revision for improvement in meeting students' demands.

The concept of customer relationship management assessment and improvement is relatively new among e‐institutions especially libraries, and there is a lack of studies focusing of CRM in the digital world. This is the first study of its kind to survey the CRM scale in digital libraries. In addition, the study provides useful insights and guidance for managers to measure and improve CRM system toward improving customer satisfaction.

The purpose of this paper is to understand the philosophical changes which underpin research and practices in project management. This study is an attempt to challenge previous studies that have tried to explain this change in order to provide a better explanation.

The authors adopt a critical review research method to challenge previous explanations of the paradigm change and definition of communication. For this purpose, philosophical and social theories and concepts have been used.

This paper proposed changing the paradigm from modernism to postmodernism and the paradigm shift, which happens from postmodernism to participation, as a better explanation for the paradigmatic change in project management. Furthermore, the important role of communication has been illustrated in the participation paradigm.

For the first time in project management, the authors attempt to clarify the role of power in this paradigmatic shift, especially because this concept is an axial concept in postmodern philosophy and a neglected concept in project management literature. In addition, communicative action theory has been used with the aim of pursuing the influence of informal power in the participation paradigm and paving the way for confronting its emerging challenges in future studies.

This paper aims to provide scholars and practitioners with an innovative method of analyzing luxury brand associations in social media (i.e. Twitter). To do so, authors investigated the alignment between luxury brand identity and luxury brand image in online communication, taking into consideration firm- and user-generated content (UGC) in the form of bloggers’ contents. This paper introduces new tools that luxury brand managers could use to manage and adapt the way they communicate and interact with their customers.

The study adopts a qualitative approach based on a content analysis of Twitter posts of six luxury fashion brands (1,334 posts) and the related Twitter electronic word-of-mouth of fashion bloggers (329 tweets).

The results show a match between luxury brand identity and luxury brand image on Twitter. Specifically, the findings indicate that both brands and bloggers stress the same dimensions of luxury (aesthetic, desirable, symbolic, restricted accessibility and hedonistic experience) confirming that the ways they communicate luxury brands to consumers are aligned. Moreover, the results suggest that luxury brands could reinforce their brand value by making more use of words that are semantically related to luxury.

This study approaches the relationship between social media and luxury brands in a novel way and provides scholars and managers with a tool for monitoring the gap between desired and perceived brand associations.