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1 – 10 of over 5000This research study aims to minimize autonomous flight cost and maximize autonomous flight performance of a slung load carrying rotary wing mini unmanned aerial vehicle (i.e. UAV…
Abstract
Purpose
This research study aims to minimize autonomous flight cost and maximize autonomous flight performance of a slung load carrying rotary wing mini unmanned aerial vehicle (i.e. UAV) by stochastically optimizing autonomous flight control system (AFCS) parameters. For minimizing autonomous flight cost and maximizing autonomous flight performance, a stochastic design approach is benefitted over certain parameters (i.e. gains of longitudinal PID controller of a hierarchical autopilot system) meanwhile lower and upper constraints exist on these design parameters.
Design/methodology/approach
A rotary wing mini UAV is produced in drone Laboratory of Iskenderun Technical University. This rotary wing UAV has three blades main rotor, fuselage, landing gear and tail rotor. It is also able to carry slung loads. AFCS variables (i.e. gains of longitudinal PID controller of hierarchical autopilot system) are stochastically optimized to minimize autonomous flight cost capturing rise time, settling time and overshoot during longitudinal flight and to maximize autonomous flight performance. Found outcomes are applied during composing rotary wing mini UAV autonomous flight simulations.
Findings
By using stochastic optimization of AFCS for rotary wing mini UAVs carrying slung loads over previously mentioned gains longitudinal PID controller when there are lower and upper constraints on these variables, a high autonomous performance having rotary wing mini UAV is obtained.
Research limitations/implications
Approval of Directorate General of Civil Aviation in Republic of Türkiye is essential for real-time rotary wing mini UAV autonomous flights.
Practical implications
Stochastic optimization of AFCS for rotary wing mini UAVs carrying slung loads is properly valuable for recovering autonomous flight performance cost of any rotary wing mini UAV.
Originality/value
Establishing a novel procedure for improving autonomous flight performance cost of a rotary wing mini UAV carrying slung loads and introducing a new process performing stochastic optimization of AFCS for rotary wing mini UAVs carrying slung loads meanwhile there exists upper and lower bounds on design variables.
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The purpose of this paper is to improve autonomous flight performance of an unmanned aerial vehicle (UAV) having actively sweep angle morphing wing using simultaneous UAV and…
Abstract
Purpose
The purpose of this paper is to improve autonomous flight performance of an unmanned aerial vehicle (UAV) having actively sweep angle morphing wing using simultaneous UAV and flight control system (FCS) design.
Design/methodology/approach
An UAV is remanufactured in the ISTE Unmanned Aerial Vehicle Laboratory. Its wing sweep angle can vary actively during flight. FCS parameters and wing sweep angle are simultaneously designed to optimize autonomous flight performance index using a stochastic optimization method called as simultaneous perturbation stochastic approximation (SPSA). Results obtained are applied for flight simulations.
Findings
Using simultaneous design process of an UAV having actively sweep angle morphing wing and FCS design, autonomous flight performance index is maximized.
Research limitations/implications
Authorization of Directorate General of Civil Aviation in Turkey is crucial for real-time UAV flights.
Practical implications
Simultaneous UAV having actively sweep angle morphing wing and FCS design process is so beneficial for recovering UAV autonomous flight performance index.
Social implications
Simultaneous UAV having actively sweep angle morphing wing and FCS design process achieves confidence, high autonomous performance index and simple service demands of UAV operators.
Originality/value
Composing a novel approach to improve autonomous flight performance index (e.g. less settling and rise time, less overshoot meanwhile trajectory tracking) of an UAV and creating an original procedure carrying out simultaneous UAV having actively sweep angle morphing wing and FCS design idea.
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The purpose of this research paper is to recover the autonomous flight performance of a mini unmanned aerial vehicle (UAV) via stochastically optimizing the wing over certain…
Abstract
Purpose
The purpose of this research paper is to recover the autonomous flight performance of a mini unmanned aerial vehicle (UAV) via stochastically optimizing the wing over certain parameters (i.e. wing taper ratio and wing aspect ratio) while there are lower and upper constraints on these redesign parameters.
Design/methodology/approach
A mini UAV is produced in the Iskenderun Technical University (ISTE) Unmanned Aerial Vehicle Laboratory. Its complete wing can vary passively before the flight with respect to the result of the stochastic redesign of the wing while maximizing autonomous flight performance. Flight control system (FCS) parameters (i.e. gains of longitudinal and lateral proportional-integral-derivative controllers) and wing redesign parameters mentioned before are simultaneously designed to maximize autonomous flight performance index using a certain stochastic optimization strategy named as simultaneous perturbation stochastic approximation (SPSA). Found results are used while composing UAV flight simulations.
Findings
Using stochastic redesign of mini UAV and simultaneously designing mini ISTE UAV over previously mentioned wing parameters and FCS, it obtained a maximum UAV autonomous flight performance.
Research limitations/implications
Permission of the directorate general of civil aviation in the Republic of Türkiye is essential for real-time UAV autonomous flights.
Practical implications
Stochastic redesign of mini UAV and simultaneously designing mini ISTE UAV wing parameters and FCS approach is very useful for improving any mini UAV autonomous flight performance cost index.
Social implications
Stochastic redesign of mini UAV and simultaneously designing mini ISTE UAV wing parameters and FCS approach succeeds confidence, highly improved autonomous flight performance cost index and easy service demands of mini UAV operators.
Originality/value
Creating a new approach to recover autonomous flight performance cost index (e.g. satisfying less settling time and less rise time, less overshoot during flight trajectory tracking) of a mini UAV and composing a novel procedure performing simultaneous mini UAV having passively morphing wing over certain parameters while there are upper and lower constraints and FCS design idea.
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Oguz Kose, Tugrul Oktay and Enes Özen
The purpose of this paper is to obtain values that stabilize the lateral and longitudinal flight of the quadrotor for which the morphing amount and the best…
Abstract
Purpose
The purpose of this paper is to obtain values that stabilize the lateral and longitudinal flight of the quadrotor for which the morphing amount and the best Proportional-Integral-Derivative (PID) coefficients are determined by using the simultaneous perturbation stochastic approximation (SPSA) optimization algorithm.
Design/methodology/approach
Quadrotor consists of body and arms; there are propellers at the ends of the arms to take off and rotors that rotate them. By reducing the angle between mechanism 1 and the rotors with the horizontal plane, the angle between mechanism 2 and the arms, the rotors rise and different configurations are obtained. Conventional multi-rotor aircraft has a fixed fuselage and does not need a tail rotor to change course as helicopters do. The translational and rotational movements are provided by the rotation of the rotors of the aircraft at different speeds by creating moments about the geometric center in 6-degree-of-freedom (DOF) space. These commands sent from the ground are provided by the flight control board in the aircraft. The longitudinal and lateral flight stability and properties of different configurations evaluated by dynamic analysis and simulations in 6 DOF spaces are investigated. An algorithm and PID controller are being developed using SPSA to achieve in-flight position and attitude control of an active deformable aircraft. The results are compared with the results of the literature review and the results of the previous article.
Findings
With SPSA, the best PID coefficients were obtained in case of morphing.
Research limitations/implications
The effects of quadrotor arm height and hub angle changes affect flight stability. With the SPSA optimization method presented in this study, the attitude is quickly stabilized.
Practical implications
With the optimization method, the most suitable PID coefficients and angle values for the lateral and longitudinal flight stability of the quadrotor are obtained.
Social implications
The transition rate and PID coefficients are determined by using the optimization method, which is advantageous in terms of cost and practicality.
Originality/value
With the proposed method, the aircraft can change shape to adapt to different environments, and the parameters required for more stable flight for each situation will be calculated, and this will be obtained more quickly and safely with the SPSA optimization method.
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Tugrul Oktay and Yüksel Eraslan
The purpose of this paper is to improve autonomous flight performance of a fixed-wing unmanned aerial vehicle (UAV) via simultaneous morphing wingtip and control system design…
Abstract
Purpose
The purpose of this paper is to improve autonomous flight performance of a fixed-wing unmanned aerial vehicle (UAV) via simultaneous morphing wingtip and control system design conducted with optimization, computational fluid dynamics (CFD) and machine learning approaches.
Design/methodology/approach
The main wing of the UAV is redesigned with morphing wingtips capable of dihedral angle alteration by means of folding. Aircraft dynamic model is derived as equations depending only on wingtip dihedral angle via Nonlinear Least Squares regression machine learning algorithm. Data for the regression analyses are obtained by numerical (i.e. CFD) and analytical approaches. Simultaneous perturbation stochastic approximation (SPSA) is incorporated into the design process to determine the optimal wingtip dihedral angle and proportional-integral-derivative (PID) coefficients of the control system that maximizes autonomous flight performance. The performance is defined in terms of trajectory tracking quality parameters of rise time, settling time and overshoot. Obtained optimal design parameters are applied in flight simulations to test both longitudinal and lateral reference trajectory tracking.
Findings
Longitudinal and lateral autonomous flight performances of the UAV are improved by redesigning the main wing with morphing wingtips and simultaneous estimation of PID coefficients and wingtip dihedral angle with SPSA optimization.
Originality/value
This paper originally discusses the simultaneous design of innovative morphing wingtip and UAV flight control system for autonomous flight performance improvement. The proposed simultaneous design idea is conducted with the SPSA optimization and a machine learning algorithm as a novel approach.
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Mayuri Srivastava, Shradha Shivani and Sraboni Dutta
The purpose of this empirical study is to enable a better understanding of the construct sustainability-oriented entrepreneurial intentions (SEI) and thereby promote sustainable…
Abstract
Purpose
The purpose of this empirical study is to enable a better understanding of the construct sustainability-oriented entrepreneurial intentions (SEI) and thereby promote sustainable entrepreneurship. It aims to examine the significance of work values (extrinsic rewards, intrinsic rewards and job security) as antecedents of SEI and to test the mediating effect of three constructs derived from the theory of planned behaviour – attitude towards sustainability, perceived entrepreneurial desirability and perceived entrepreneurial feasibility on the relationships between work values and SEI.
Design/methodology/approach
Confirmatory factor analysis and exploratory factor analysis were performed using analysis of moment structures v27 and statistical package for social science v28 on data obtained from the survey of young individuals of India. The respondents were students enrolled in higher education programmes.
Findings
All the identified antecedents (extrinsic rewards, intrinsic rewards, job security and theory of planned behaviour constructs) were found to be statistically significant. The partial mediating effect of the theory of planned behaviour constructs was also reported.
Originality/value
This empirical work leads to the theoretical advancement of the emerging construct, SEI, by presenting evidence of the significant individual-level antecedents of the construct. The results lead to recommendations for policymakers and educators to design strategies to strengthen SEI, thereby expanding the adoption of sustainable entrepreneurship.
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Frank Grave, Rogier van de Wetering and Rob Kusters
Despite the relevance of how enterprise architecture (EA) contributes to organizational performance in contemporary digital technology-driven strategic renewal, little is known…
Abstract
Purpose
Despite the relevance of how enterprise architecture (EA) contributes to organizational performance in contemporary digital technology-driven strategic renewal, little is known about the position of EA artifacts. Therefore, this study aims to build an integrative model of EA artifact-enabled EA value supplemented with a research agenda to enhance our understanding further.
Design/methodology/approach
This study leveraged grounded theory techniques and a systematic review approach to develop the integrative model and research agenda.
Findings
We inductively build a model of the position of EA artifacts in EA value creation. Additionally, we elaborate a research agenda that proposes (1) an investigation of the role of an EA practice in successful strategic change, (2) an examination of how to manage EA practice value generation and (3) longitudinal research to gain insight into the evolution of value creation by EA practices.
Originality/value
This study presents a model of EA artifact-enabled EA value, thereby contributing to our understanding of the mechanisms, inhibitors and success factors associated with EA value. Following our model, the proposed research agenda contains future research areas to help us better understand the mechanisms and interrelatedness of EA practices in highly dynamic environments.
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The study aims to investigate the influence of leader mindfulness on employee innovative work behaviour mediated by work engagement and moderated by employee learning orientation.
Abstract
Purpose
The study aims to investigate the influence of leader mindfulness on employee innovative work behaviour mediated by work engagement and moderated by employee learning orientation.
Design/methodology/approach
That data set of 337 was collected from full-time working professionals from IT industry in India through survey design. The proposed mediated moderation model was tested through Process Macro.
Findings
The findings highlighted the positive role of leader mindfulness in enhancing employee innovative work behaviour. Furthermore, the authors found that this relationship was partly mediated by work engagement and moderated by employee learning orientation. Results suggested that the relationship between work engagement and innovative work behaviour was stronger for employees who score high on learning orientation.
Originality/value
The main contribution of the study lies in delineating the interpersonal lens of mindfulness at workplace, particularly the leader–employee interface. It offers a more nuanced delineation of the process through which leader mindfulness encourages employee innovative work behaviour.
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Chelsey Sara Taylor, Michael L. Naraine, Katie Rowe, Jonathan Robertson and Adam Karg
The purpose of this study was to explore the process of change in existing professional sport organisations as they initiate a women's team.
Abstract
Purpose
The purpose of this study was to explore the process of change in existing professional sport organisations as they initiate a women's team.
Design/methodology/approach
Three Australian Football League clubs with licenses for professional women's teams were examined, with semi-structured interviews held with three key department managers from each club.
Findings
The findings suggest organisations adopt either a community-focused or commercially focused approach, the selection of which is a response to the interplay of institutional pressures (e.g. league demands), resource demands (e.g. human and financial) and the strategic choices of a few, key “idea champions”.
Originality/value
This study provides insight into the approach change taken by clubs as they introduce a women's team into their existing organisational structure.
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Andrey Pavlov and Pietro Micheli
Traditional approaches to organizational performance management that emphasize objectivity, control and predictability are rapidly losing relevance in an environment characterized…
Abstract
Purpose
Traditional approaches to organizational performance management that emphasize objectivity, control and predictability are rapidly losing relevance in an environment characterized by increasing levels of complexity and dynamism. This paper draws on complexity theory to suggest a new paradigm for managing performance in organizations.
Design/methodology/approach
The paper draws on the common features of complex systems and the corresponding concept of emergence to revisit key themes in organizational performance management and propose a set of implications for research and practice.
Findings
Understanding organizations as complex systems and performance as an emergent property of such systems leads to a set of new research questions, the adoption of alternative methods and the formulation of novel propositions. It also has various implications for both academic research and managerial practice, from moving away from the traditional notion of organizational alignment to adopting a more explicit stakeholder-based view in the design and use of measurement systems.
Originality/value
The paper highlights the great potential of complexity theory for addressing contemporary issues in the field of organizational performance management and charting the landscape for its future development.
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